ARTICLE | doi:10.20944/preprints202302.0467.v1
Subject: Medicine And Pharmacology, Hematology Keywords: Diagnostic; Iron deficiency; Polycythemia; Polycythemia vera; Secondary polycythemia
Online: 27 February 2023 (09:36:45 CET)
Several observations have shown that patients with polycythemia have iron deficiency. Our objectives were to report the prevalence of iron deficiency, to evaluate the diagnostic performance of serum ferritin in polycythemia vera and to describe the mechanisms of this association. This is a retrospective descriptive and analytical study carried out in the internal medicine department of the Henri Mondor Hospital, Aurillac, France. The study involved 114 patients with polycythemia, followed in the department from January 1, 2010 to December 31, 2021. To evaluate the diagnostic performance, the JAK2 mutation was considered as the gold standard of diagnosis. Thirty-three patients had polycythemia vera and 76 patients had secondary polycythemia. The mean age of the patients was 61.79 years (±15.44) with a sex ratio of 4.43. The overall prevalence of iron deficiency was 21.05%. The prevalence was 53% in polycythemia vera group and 1.32% in secondary polycythemia group. The risk of iron deficiency was high in polycythemia vera (OR=115; 95% CI [14.4-918.2], p<0.000). The sensitivity and specificity of serum ferritin were 52.63% and 100% respectively. Assessment of iron deficiency should be part of the initial evaluation of polycythemia. The presence of iron deficiency is specific for polycythemia vera.
REVIEW | doi:10.20944/preprints201810.0189.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: hepcidin, iron deficiency anemia, iron dextran, neonatal period, pig, supplementation
Online: 9 October 2018 (15:34:13 CEST)
In pigs, iron deficiency anemia (IDA) is the most prevalent deficiency disorder during the early postnatal period frequently developing into a critical illness. Meanwhile, in humans, only low-birth-weight infants, including premature infants are especially susceptible to developing IDA. In both human and pig neonates, the initial cause of IDA is low birth iron stores. In piglets this shortage of stored iron results mainly from genetic selection over the past few decades for large litter size and high birth weight. In consequence, pregnant sows cannot provide sufficient amount of iron to the increasing number of developing fetuses. Supplementation with iron is a common practice for the treatment of IDA in piglets. For decades, the preferred procedure for delivering iron supplements during early life stages has been through the intramuscular injection of large amount of iron dextran. However, this relatively simple therapy, which in general, efficiently corrects IDA, may generate toxic effects, and by inducing hepcidin expression, may decrease bioavailability of supplemental iron. New iron supplements are considered now with the aim to combine improvement of hematological status, blunting hepcidin expression, and minimizing toxicity of the administered iron. We propose that iron-deficient piglets constitute a convenient animal model for performing pre-clinical studies with iron supplements.
ARTICLE | doi:10.20944/preprints201807.0422.v1
Online: 23 July 2018 (12:34:21 CEST)
Ghrelin and obestatin, two antagonist peptide hormones, are purportedly involved in stimulating appetite and controlling energy balance in humans. Serum ghrelin level is also associated with iron deficiency anemia (IDA), but no study has yet been made of the obestatin level in patients with IDA, even though both hormones are a single gene product. Therefore, the purpose of this investigation is to see whether there is a link between IDA and these two hormones among other hematological parameters in patients with IDA. To measure ghrelin and obestatin, human saliva and serum were collected from 30 women with IDA, aged 31.7 ± 10.7 years, and 30 control women, aged 30.2 ± 8.0 years, with repeated collection of samples over a period of 1 week and 1 month. Saliva and serum ghrelin levels were measured by ELISA. Serum hemoglobin, ferritin, hematocrit and total iron-binding capacity (TIBC) values were determined with an Olympus AU2700. Saliva and serum ghrelin and obestatin levels were significantly lower in the IDA group compared with controls; these levels increased slightly above baseline with iron treatment, but remained below the control values. Furthermore, and as expected, serum hemoglobin, ferritin, and hematocrit levels were significantly increased with iron treatment, while total iron-binding capacity decreased compared to baseline concentrations. The findings suggest that IDA might be linked to imbalance of circulating (serum) and non-circulating (saliva) ghrelin and obestatin levels. Decreased ghrelin and obestatin might destroy iron homeostasis through its effect on intestinal absorption. Measuring these hormone levels might be useful for monitoring the response to iron treatment. Also, serum and saliva levels for both hormones were well correlated. Thus, using saliva in place of serum for monitoring the two hormones should minimize inconvenience and patient discomfort.
ARTICLE | doi:10.20944/preprints202309.0503.v1
Subject: Public Health And Healthcare, Primary Health Care Keywords: iron deficiency anemia; IDA; anemia; knowledge; awareness
Online: 7 September 2023 (11:13:08 CEST)
Keywords: iron deficiency anemia; IDA; anemia; knowledge; awareness.
ARTICLE | doi:10.20944/preprints202304.0600.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: IDA mice; Antarctic krill peptide-iron; iron-regulated genes; iron bioavailability; in vivo antioxidant capacity
Online: 20 April 2023 (03:15:22 CEST)
Antarctic krill protein-iron complex and peptide-iron complex were obtained to investigate their iron bioavailability, expression of iron-regulated genes, and in vivo antioxidant capacity. Results indicated that Antarctic krill peptide-iron complex increased significantly the hemoglobin (Hb), serum iron (SI) and iron content in the liver and spleen in iron-deficiency anemia (IDA) mice (P < 0.05) compared with those of Antarctic krill protein-iron complex. Despite the gene expressions of divalent metal transporter 1(DMT1), transferrin (Tf) and transferrin receptor (TfR) could be better regulated by both Antarctic krill peptide-iron complex and protein-iron complex, the relative iron bioavailability of the Antarctic krill peptide-iron complex group (152.53±21.05%) was significantly higher than that of the protein-iron complex group (112.75±9.60%) (P<0.05). Moreover, Antarctic krill peptide-iron complex could enhance the antioxidant enzyme activities of superoxidase dismutase (SOD) and glutathione peroxidase (GSH-Px), reduce the malondialdehyde (MDA) level in IDA mice compared with the protein-iron complex, reducing the cell damage caused by IDA. Therefore, these results demonstrated that Antarctic krill peptide-iron complex could be used as a highly efficient and multifunctional iron supplement.
ARTICLE | doi:10.20944/preprints202107.0166.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Pica; iron deficiency anemia; Relationship; pregnant women
Online: 7 July 2021 (07:54:39 CEST)
INTRODUCTION. The most common cause of eating non-food items (pica) is specific deficiencies of minerals, such as iron. This study aimed to assess the relationship between Pica and Iron deficiency anemia among pregnant women. METHODS. The study was conducted in the out-patient department, antenatal Clinic at East Jeddah Hospital from July to September 2020. Design: A quantitative descriptive correlation design. Sample size: A total of 400 pregnant women, included anemic pregnant women, ≥ 18 years old, with singleton fetus and iron deficiency anemia. RESULTS. The mean age was 32.2 ± 6.6, half of the participants reported food cravings. Ice was the main item in pica followed by clay and chalk. Two-thirds had pica, more than half during the 1st trimester. There is a statistically significant relationship between pica and the history of a family member, parity, and gravidity at (P< 0,001, P <0,001, P <0,005) respectively. Hb and hematocrit in relation to pica reflected a statistically significant relationship (P< 0,001) and (P< 0,001), respectively. The symptoms attributed to iron deficiency were significantly associated with pica (P< 0,006). CONCLUSION. The pica and iron deficiency anemia had a significant association with pregnant women in EJH. RECOMMENDATION. The follow-up visits should integrate the food behavior inquiry to check if the pica existing with anemic or non-anemic pregnant women. Also, increase the awareness among midwives-nurses about the prevalence of pica and iron deficiency anemia among pregnant women.
ARTICLE | doi:10.20944/preprints201704.0053.v1
Subject: Medicine And Pharmacology, Orthopedics And Sports Medicine Keywords: iron deficiency anemia; osteoporosis; ferrum infusion; blood transfusion
Online: 10 April 2017 (06:32:56 CEST)
The cause-effect relationship between iron deficiency anemia (IDA) and osteoporosis has not been established in the general population. Thus, the current longitudinal study determined the role of IDA as a risk factor for osteoporosis by analyzing a large nationwide population-based sample. In a sample of 1,000,000 randomly sampled individuals from the 1998-2012 Taiwan National Health Insurance Research Database, patients with IDA (case group [n=35,751]) and individuals without IDA (control group [n=178,755]) were compared. Patients who were <20 years of age and who had pre-existing osteoporosis prior to the diagnosis of IDA were excluded. Each patient with IDA was age- and gender-matched to 5 individuals without IDA. The diagnoses of IDA and osteoporosis (coded using ICD-9CM) were further confirmed with blood test results and X-ray bone densitometry to ensure the accuracy of the diagnoses. Osteoporosis occurred more often among patients with IDA compared to individuals without IDA (2.27% vs. 1.32%, p<0.001). Cox proportional hazard analysis revealed that the risk for osteoporosis was significantly higher in the case than the control group (hazard ratio [HR]=1.74; 95% CI=1.61-1.88) and remained similar after adjustment for covariates (adjusted HR=1.81; 95% CI=1.67-1.97). Compared with individuals without IDA, the risk for osteoporosis was even higher for patients with IDA who received intravenous ferrum therapy (adjusted HR=2.21; 95% CI=1.85-2.63). In contrast, the risk for osteoporosis was reduced for patients with IDA who received a blood transfusion (adjusted HR=1.47; 95% CI=1.20-1.80). As a predictor, prior IDA is a significant and independent risk factor for development of osteoporosis. In contrast to blood transfusion treatment, the use of intravenous ferrum may further increase the risk for future osteoporosis.
ARTICLE | doi:10.20944/preprints202304.0058.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Aerobic Rice; Chlorosis; Iron Deficiency; Oryza; Wild Germplasm; IDIC; SPAD
Online: 5 April 2023 (11:34:36 CEST)
Transplanted rice cultivation has caused groundwater depletion in several regions globally. Direct-seeded rice under aerobic conditions is a water-saving alternative. However, under aerobic conditions, iron in the soil is oxidized from ferrous to ferric, which is not easily available for rice, resulting in iron deficiency induced chlorosis (IDIC) causing significant reduction in yield. Cultivated rice genotypes have limited variations for IDIC tolerance, while wild Oryza germplasm could be a potential source for IDIC tolerance. In this study, 313 Oryza accessions were evaluated for IDIC tolerance at the tillering stage under aerobic conditions and twenty IDIC tolerant lines were identified. The twenty lines showed no signs of chlorosis and had high levels of iron content and SPAD values, while eight cultivated controls exhibited varying degrees of chlorosis symptoms and low levels of SPAD and iron content. To confirm their tolerance, the selected lines were evaluated again in a subsequent year, and they showed comparable levels of tolerance indicating these lines were efficient in iron uptake and utilization resulted maintained high chlorophyll and leaf area index. These accessions may be useful for developing IDIC-tolerant cultivars for aerobic rice cultivation and future study of molecular basis of IDIC tolerance.
ARTICLE | doi:10.20944/preprints201907.0254.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: economic evaluation, micronutrient fortification, iron deficiency anemia, Cote d’Ivoire, model, impact, DALYs
Online: 23 July 2019 (10:25:26 CEST)
Iron deficiency anemia (IDA) is highly prevalent in the Cote d’Ivoire, and has severe health and economic consequences. In this paper, we apply a health economic model to quantify the burden of IDA, and the contribution of nation-wide mandatory iron fortification of wheat flour and voluntary iron fortification of condiments to the reduction of this burden. The analysis for the population from six months to 64 years builds on published reviews and publicly available datasets, and is stratified by age-groups and socio-economic strata. Without the impact of these fortification strategies, the annual burden of IDA is estimated at 242,100 disability adjusted life years (DALYs) and 978.1 million USD. Wheat flour and condiment fortification contributed to a reduction of the IDA burden by approximately 5% each. In places with high prevalence of malaria and environmental factors, such as the Côte D’Ivoire, policy makers should combine nutritional intervention with infectious disease prevention and environmental factors. The findings of this study provide additional input for policy makers about the magnitude of the impact and can support the conception of future fortification strategies.
ARTICLE | doi:10.20944/preprints201701.0126.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: anemia; iron deficiency; pregnancy; serum ferritin; mean corpuscular volume (mcv); mean corpuscular hemoglobin (MCH); Northern Pakistan
Online: 27 January 2017 (03:46:07 CET)
Abstract: The aim of this study was to find out the incidence of anemia in pregnant women of Swat District; to analyze the iron variations and its dietary effects.Data were collected during the periods of January – September 2016. The study of samples comprised of 250 pregnant women in the different trimester. Blood sample from each woman was collected and full blood count (FBC) was conducted through Mindray BC-3000 plus hem analyzer for all pregnant individuals. Confirmed anemic cases were then examined for IDA with serum ferritin, serum iron, total iron binding capacity (TIBC) through Randox kit and serum transferrin saturation was estimated by formula (serum ferritin saturation =serum iron ×100/TIBC). The total number of participants in the first trimester were 50, among them 26 women were suffer from iron deficiency anemia (IDA) with 52% weightage of prevalence rate, (mean Hb concentration 9.602 ± 0.87 g/dl). The rates of IDA were 63.3%; ( mean Hb concentration 8.48 ± 1.24 g/dl) and 54%; ( mean Hb concentration 9.18 ± 1.28 g/dl), among 150 and 50 participants in the second and third trimester, respectively. A significant correlation was found between serum ferritin and Hb, serum ferritin against MCV and serum ferritin against MCH. The high prevalence of anemia was found 78.2% in the age group from 26-30 followed by 78.2% in the age group 36-40 years compared to those of other age groups in the second trimester. In this study the prevalence of IDA in third trimester is lower compared to first and second trimester.
ARTICLE | doi:10.20944/preprints202003.0071.v1
Subject: Medicine And Pharmacology, Cardiac And Cardiovascular Systems Keywords: Anemia classification; dynamic harmony search; iron deficiency anemia; thalassemia trait; machine learning
Online: 4 March 2020 (15:34:04 CET)
In recent decades, attention has been directed at anemia classification for various medical purposes, such as thalassemia screening and predicting iron deficiency anemia (IDA). In this study, a new method has been successfully tested for discrimination between IDA and β-thalassemia trait (β-TT). The method is based on a Dynamic Harmony Search (DHS). Complete blood count (CBC), a fast and inexpensive laboratory test, is used as the input of the system. Other models, such as a genetic programming method called structured representation on genetic algorithm in non-linear function fitting (STROGANOFF), an artificial neural network (ANN), an adaptive neuro-fuzzy inference system (ANFIS), a support vector machine (SVM), k-nearest neighbor (KNN), and certain traditional methods, are compared with the proposed method.
ARTICLE | doi:10.20944/preprints202102.0445.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Iron; Vitamin D; Vitamin B12; Roux-en-Y gastric bypass; Sleeve gastrectomy; Adjustable gastric banding; nutritional deficiency; bariatric surgery
Online: 19 February 2021 (14:36:21 CET)
Long-term nutritional studies in subjects undergoing bariatric surgery that have assessed weight regain and nutritional deficiencies are few. In this study, we report data 8 years after surgery on weight loss, use of dietary supplements and deficit of micronutrients in a cohort of patients from five centres in central and northern Italy. The study group consisted of 52 subjects (age: 38.1±10.6 yrs, 42 females): 16 patients had Roux-en-Y gastric bypass (RYGB), 25 patients sleeve gastrectomy (LSG) and 11 subjects adjustable gastric banding (AGB). All three bariatric procedures led to sustained weight loss: average percentage excess weight loss, defined as weight loss divided by excess weight based on ideal body weight was 60.6%±32.3. 80.7% of subjects (72.7%, AGB; 76%, SG; 93.7%, RYGB) reported at least one nutritional deficiency: iron (F 64.3% vs. M 30%), vitamin B12 (F 16.6% vs. M 10%), calcium (F 33.3% vs. M 0%) and vitamin D (F 38.1% vs. M 60%). Average weight loss was constant in RYGB and SG subjects from the third year after surgery. Long-term nutritional deficiencies were greater than the general population among men for iron and among women for vitamin B12.
REVIEW | doi:10.20944/preprints202311.1158.v1
Subject: Medicine And Pharmacology, Hematology Keywords: iron deficiency; iron deficiency anemia; intravenous iron; iron sucrose; ferric carboxymaltose; iron isomaltoside; inflammatory bowel diseases
Online: 20 November 2023 (02:41:19 CET)
Iron deficiency (ID) is by far the most common nutritional disorder in developing and developed countries. When left untreated, ID leads to anemia. Although the usual recommended treatment for iron deficiency anemia (IDA) is oral iron therapy with countless products, such therapy necessitates administration for >3-6 months with questionable patient compliance since most oral iron products have an unpleasant metallic aftertaste and cause intestinal side effects. In addition, in certain gastrointestinal conditions, such as inflammatory bowel diseases or untreated gluten-sensitive enteropathy, oral iron therapy is contraindicated or unsuccessful. Intravenous iron is considered safe in adults, where adverse events are mild and easily managed. The experience with parenteral iron in children is much more limited and many pediatricians appear reluctant to use it because of uncorroborated fears of serious anaphylactic reactions. In the current article, we thoroughly review the available pediatric literature on the use of all commercially available parenteral iron products except ferumoxytol, which was recently removed from the market. We conclude that parenteral iron appears to be safe in children, it works faster than oral iron and the newer third-generation products allow replacement of the total iron deficit at a single setting.
ARTICLE | doi:10.20944/preprints202307.1234.v1
Subject: Medicine And Pharmacology, Hematology Keywords: Iron deficiency anemia; oral iron; side effects
Online: 18 July 2023 (14:17:18 CEST)
Introduction: In the recent years alternate day dosing has been recommended in iron deficieny treatment. The aim of this study is to compare the efficacy and side effects of oral iron treatments given daily 1x1, alternate day 1x1 and 2x1 alternate day dosing in iron deficieny anemia patients. Methods: A total of 52 patients with a diagnosis of iron deficiency anemia with serum ferritin level of 25 µg/L or less were included in this retrospective study. Statistical analyzes were done with SPSS V.25. Results: The patients included in our study were between the ages of 18-51. All of the patients included in the study were female. A statistically significant increase was found between 0-14 days(p<0.001), 14-28 days(p<0.001) and 0-28 days(p<0.001) hemoglobin values in all patients. There was no statistically significant difference between 0-14 days (p=0.397) and 0-28 days(p=0.310) ferritin values in all patients. A statistically significant difference was found between 14-28 days(p<0.001) ferritin values. When the rate of change of hemoglobin and ferritin values between the groups was compared and no statistically significant difference was observed between the groups. The rate of change of ferritin values for 14-28 days was significant (p=0.012). There was no significant difference in the frequency of symptoms in the 14th day and 28th day controls for each group (p>0.05). The incidence of metallic taste and bloating symptoms was found to be statistically significant in the third control in the group with 2x1 drug use alternate day (p=0.094). Discussion: The only difference in efficacy was observed in ferritin values between 14th and 28th days. The increase in ferritin values was higher in the group that used 1x1 oral iron every day. However, since no difference was observed between the groups in terms of ferritin and hemoglobin values on days 0 and 28, all three groups were considered equally efficient. Side effects were mainly gastrointestinal side effects. Since the group that received 2x1 oral treatment alternate day had a statistically significantly higher rate of side effects, the patients’ treatment tolerance will be lower compared to the other groups. In conlusion, there is no difference in efficacy and side effects between the patient groups receiving 1x1 daily and 1x1 alternate day oral iron therapy, so 1x1 use alternate day is the most appropriate treatment method for oral iron therapy in terms of patient tolerance, adherence to treatment and pharmacoeconomics.
REVIEW | doi:10.20944/preprints202306.0213.v1
Subject: Medicine And Pharmacology, Hematology Keywords: β-thalassemia; iron overload; iron chelators; TDT; NTDT
Online: 2 June 2023 (14:27:31 CEST)
β-thalassemia, a congenital genetic hematological disorder characterized by decreased or absence of β-globin chains, leads to decrease in levels of Hemoglobin A. The affected individuals can be categorized into two cohorts based on transfusion dependency: transfusion dependent thalassemia (TDT) and non-transfusion dependent thalassemia (NTDT). Remarkably, despite the primary pathology lying in β-globin chain depletion, β-thalassemia exhibits an intriguing association with iron overload. Iron metabolism, a tightly regulated physiological process, reveals a complex interplay in these patients. Over time, both cohorts of β-thalassemic individuals develop iron overload, albeit through distinct mechanisms. Addressing the diverse complications arising due to iron overload in β-thalassemic patients, the utilization of iron chelators has gained a lot of significance. With varying efficacies, routes of administration, and modes of action, different iron chelators offer unique benefits to patients. In the Indian context, three commercialized iron chelators have emerged, showcasing a high adherence rate to the iron chelator-based treatment regimens among β-thalassemic individuals. In this review, we explore the intriguing connection between β-thalassemia and iron overload, shedding light on the intricate mechanisms at play. We delve into the intricacies of iron metabolism, unveiling the distinct pathways leading to iron accumulation in these patients. Additionally, we critically evaluate the therapeutic efficacy of different iron chelators, emphasizing their respective advantages in managing iron overload complications. Through this comprehensive analysis, we aim to deepen our understanding of β-thalassemia and iron overload, paving the way for optimized treatment strategies. Ultimately, our findings provide valuable insights into improving the care and outcomes of individuals affected by β-thalassemia.
ARTICLE | doi:10.20944/preprints202212.0353.v1
Subject: Chemistry And Materials Science, Metals, Alloys And Metallurgy Keywords: synthetic cast iron; charge materials; steel scrap; nitrogen in cast iron iron; mechanical properties
Online: 20 December 2022 (04:05:55 CET)
In the field of metallurgy, there are many factors that influence the final quality of cast iron. These are mainly charge materials, chemical composition, metallurgical preparation up to the final casting process. Even small deviations from metallurgical processing lead to fluctuations in melt quality and the occurrence of casting defects. Charge materials has a significant impact on the quality of cast iron, especially steel scrap, which is increasingly used from an economic and ecological point of view, especially when melting cast iron in electric furnaces. Cast iron produced from a higher proportion of steel scrap in the charge has higher hardness and tensile strength. On the other side, these cast irons has a higher tendency to chillout, brittleness, shrinkage, pearlitic microstructure, stresses and higher purity due to the difference in hardness at different wall thicknesses of the castings. It is the high hardness that is the problem in the final machining of castings. These negative properties are recorded mainly in heavy thick-walled castings with higher tensile strength and hardness. This negative effect is mainly due to the nitrogen content in the steel scrap. Based on these knowledges, operating melts were realized in the foundry's operating conditions. The influence of steel scrap in the charge and the possibility of eliminating its negative effects on the properties of cast iron were investigated.
REVIEW | doi:10.20944/preprints202305.1989.v1
Subject: Medicine And Pharmacology, Medicine And Pharmacology Keywords: Iron chelation; Iron overload; kidney disease; deferoxamine; deferasirox; deferiprone
Online: 29 May 2023 (07:26:02 CEST)
Background: Iron chelation medications (desferoxamine, desferasirox, desferiprone) are used to manage iron overload. These medications are partially excreted via the kidneys, desferoxamine and desferiprone excretes primarily in the urine, and desferasirox had about 8% excreted in the urine. Their use in severe kidney disease and dialysis patients is caution as “avoided” concerning adverse effects; however, there are reports safe use. This manuscript reviews the literature in this population. Data Sources: Pubmed: desferasirox, deferiprone, deferoxamine, kidney disease, ESKD, Dialysis. Case reports and case series that described experiences with using iron chelation medications in ESKD patients are included. Data also gathered from reading-related sources. Results: This is a review of desferoxamine, desferasirox, and deferiprone use in kidney disease from 1976 to the present time. Table 1 provides a summary of findings. These are mostly reports and brief descriptions of the experiences used in severe kidney disease and dialysis, but lack of randomized control trials and small number of participants. Conclusions: Iron chelation medications are important for treating iron overload but concerns with adverse effects. Due to limited medications available to treat iron overload in patients with severe kidney disease, their safe use has been reporting in the literature. This is an area that warrants further research.
ARTICLE | doi:10.20944/preprints202306.0429.v1
Online: 6 June 2023 (09:43:32 CEST)
Many theoretical models of iron-based superconductors have been proposed but Tc calculations based on the models are usually missing. We have chosen two models of iron-based superconductors in the literature and then compute the Tc values accordingly: Recently two models have been announced which suggest that superconducting electron concentration involved in the pairing mechanism of iron-based superconductors may have been underestimated, and that the antiferromagnetism and the induced xy potential may even have a dramatic amplification effect on electron-phonon coupling. We use bulk FeSe, LiFeAs and NaFeAs data to calculate the Tc based on these models and test if the combined model can predict the superconducting transition temperature (Tc) of the nanostructured FeSe monolayer well. To substantiate the recently announced xy potential in the literature, we create a two-channel model to separately superimpose the dynamics of the electron in the upper and lower tetrahedral plane. The results of our two-channel model support the literature data. While scientists are still searching for a universal DFT functional that can describe the pairing mechanism of all iron-based superconductors, we base on the ARPES data to propose an empirical combination of DFT functional for revising the electron-phonon scattering matrix in the superconducting state, which ensures that all electrons involved in iron-based superconductivity are included in the computation. Our computational model takes into account this amplifying effect of antiferromagnetism and the correction of the electron-phonon scattering matrix together with the abnormal soft out-of-plane lattice vibration of the layered structure, which allows us to calculate theoretical Tc values of LiFeAs, NaFeAs and FeSe as a function of pressure that correspond reasonably well to the experimental values. More importantly, by taking into account the interfacial effect between an FeSe monolayer and its SrTiO3 substrate as an additional gain factor, our calculated Tc value is up to 91 K high, and provides evidence that the strong Tc enhancement recently observed in such monolayers with Tc reaching 100 K may be contributed from the electrons within the ARPES range.
ARTICLE | doi:10.20944/preprints202308.1352.v1
Subject: Medicine And Pharmacology, Urology And Nephrology Keywords: oral iron absorption; ferric citrate hydrate; hemodialysis; hepcidin-25; iron shift
Online: 18 August 2023 (11:20:29 CEST)
Oral ferric citrate hydrate (FCH) is effective for iron deficiency in hemodialysis patients.; however, it remains unclear how iron balance in the body affects iron absorption from the intestinal tract. This prospective, observational study (Riona-Oral Iron Absorption Trial, R-OIAT, UMIN 000031406), conducted at 42 hemodialysis centers in Japan, wherein 268 hemodialysis patients without inflammation were enrolled and treated with a fixed amount of FCH for 6 months. We assessed the predictive value of hepcidin-25 for iron absorption and iron shift between ferritin (FTN) and red blood cells (RBCs) following FCH therapy. Serum iron changes at 2 h (ΔFe2h) after FCH ingestion were evaluated as iron absorption. The primary outcome was the quantitative delineation of iron variables on ΔFe2h and the secondary outcome was the description of the predictors of body iron balance. Generalized estimating equations (GEE) were used to identify the determinants of iron absorption during each phase of FCH treatment. ΔFe2h increased when hepcidin-25 and MCH decreased (-0.155, -0.242 to -0.068, p = 0.001; -2.574, -4.421 to -0.726, p = 0.006, respectively) in GEE. Hepcidin-25 increased when erythropoiesis-stimulating agent (ESA) decreased (-0.002, -0.002 to -0.001, p=0.000). FTN increased when RBC and ESA decreased (-0.466, -0.605 to -0.327, p=0.000; -0.002, -0.004 to -0.000, p=0.05, respectively. Limiting erythropoiesis to maintain hemoglobin levels induces RBC reduction in hemodialysis patients, resulting in increased hepcidin-25 and FTN levels. Hepcidin-25 production may prompt an iron shift from RBC-iron to FTN-iron, inhibiting iron absorption even with continued FCH intake.
ARTICLE | doi:10.20944/preprints202305.0183.v1
Subject: Medicine And Pharmacology, Dietetics And Nutrition Keywords: Iron; inflammation; EGCG; hepcidin
Online: 4 May 2023 (04:14:52 CEST)
Inflammation is an underlying problem for many disease states and has been implicated in iron deficiency (ID). This study aimed to determine whether iron status is improved by epigallocate-chin-3-gallate (EGCG) through reducing inflammation. Thirty-two male Sprague-Dawley rats were randomly divided into four groups (n = 8 each): positive controls, negative controls, lipo-polysaccharide (LPS, 0.5 mg/kg body weight), and LPS + EGCG (LPS plus 600 mg EGCG/kg diet). Iron status, hepcidin, C - reactive protein (CRP), serum amyloid A (SAA), and interleukin-6 (IL-6) were measured. There were no differences in treatment groups compared with control in CRP, hepcidin, and liver iron concentrations. Serum iron concentrations were significantly lower in the LPS (p=0.02) and the LPS+EGCG (p=0.01) than in the positive control group. Compared to the positive control group, spleen iron concentrations were significantly lower in the negative con-trol (p<0.001) but not with both LPS groups. SAA concentrations were significantly lower in LPS + EGCG group compared to LPS alone group. IL-6 concentrations were significantly higher in LPS+EGCG (p= 0.004) than in any of the three groups. EGCG reduced SAA concentrations but did not affect hepcidin or improve serum iron concentration or other iron markers.
REVIEW | doi:10.20944/preprints202304.0859.v1
Subject: Medicine And Pharmacology, Other Keywords: Iron deficiency; iron overload; anemia; heme; metabolic syndrome; cardiovascular disease; cancer; microbiome
Online: 24 April 2023 (12:48:31 CEST)
Dietary iron assimilation is critical for health and essential to prevent iron deficient states and related comorbidities, such as anemia. The bioavailability of iron is limited, while its absorption and metabolism are tightly controlled to keep body iron stores within a relatively narrow range. Genetic inactivation of the iron hormone hepcidin causes hereditary hemochromatosis, an endocrine disorder of iron overload characterized by chronic hyperabsorption of dietary iron, with deleterious clinical complications if untreated. The impact of high dietary iron intake and elevated body iron stores in the general population is not well understood. Herein, we summarize epidemiological data suggesting that high intake of heme iron, which is abundant in meat products, poses a risk factor for metabolic syndrome pathologies, cardiovascular diseases, and some cancers. We discuss clinical relevance and potential limitations of data from cohort studies, as well as the need to establish causality and elucidate molecular mechanisms.
ARTICLE | doi:10.20944/preprints202309.1338.v1
Subject: Medicine And Pharmacology, Hematology Keywords: iron chelation; iron overload; myelodysplastic syndromes; MDS; myeloproliferative neoplasms; MPN; ferritin; hematologic improvement
Online: 20 September 2023 (05:39:06 CEST)
Myelodysplastic syndromes and myeloproliferative neoplasms both represent hematologic diseases associated with bone marrow failure often resulting in anemia. For those patients, transfusion of red blood cell (RBC) units is essential, but results in iron overload (IOL) that may affect various organ functions. Therefore, iron chelation therapy plays a major role in anemic patients, not only because it reduces IOL, but also because it may improve hematopoietic function by increasing hemoglobin or diminishing requirement of RBC transfusions. To assess the utility, efficacy and safety of the different iron chelation medication approved in Germany as well as to examine the effect of chelation on hematopoietic insufficiency, a prospective, multicenter, non-interventional study named EXCALIBUR was designed. In total, 502 patients from 106 German hospitals and medical practices were enrolled. A large proportion of patients switched from deferasirox dispersible tablet to deferasirox film-coated tablet, mainly due to more convenient application which was reflected in the treatment satisfaction questionnaire for medication scores. Iron chelation was effective in lowering serum ferritin levels, with the observed adverse drug reactions being in line with the known safety profile. Hematologic response occurred in a few patients, comparable to other studies that examined hematologic improvement in patients with MDS.
COMMUNICATION | doi:10.20944/preprints202309.1053.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Oligodendroglioma; iron; pediatric; brain tumors
Online: 15 September 2023 (09:40:22 CEST)
Oligodendroglioma (OG) is a brain tumor that contributes to < 1% of brain tumor diagnoses in the pediatric population. Unfortunately, pediatric OG remains without definitive molecular characteristics to aid in diagnosis, and little is known about the tumor microenvironment. Tumor cells' metabolism and proliferation rate are generally higher than healthy cells, so their iron demand is also significantly increased. This consideration underlines the great importance of iron for tumor development and progression. In this context, this study aims to evaluate the effect of iron in a cellular in vitro model of human oligodendroglioma brain tumor. Cell morphology, the effect of siderotic medium on cell growth, iron uptake, and the expression of iron metabolism-related genes were evaluated by optic microscopy, ICP-MS, confocal microscopy, and RealTime PCR, respectively. This study underlines the great importance of iron for tumor development and progression, but also the possibility of reducing the available iron concentration to determine an antiproliferative effect on OGs. Therefore, every attempt can be promising to defeat the OGs for which there are currently no long-term curative therapies.
ARTICLE | doi:10.20944/preprints202305.1739.v1
Subject: Environmental And Earth Sciences, Soil Science Keywords: Soil geochemistry pyrites; iron partitioning
Online: 25 May 2023 (05:24:51 CEST)
Baía de Todos os Santos is the second largest bay in Brazil and is home to important ecosystems, including estuarine systems and mangroves. However, studies on the seasonal variability of its soil properties and composition are still scarce. For this study, soil and leaf samples were seasonally collected from mangrove forests at four sites (Cacha Prego, Ponta Grossa, Ilha de Maré, and Pitinga), which are representative of different environmental conditions within the BTS. Soil physicochemical properties, soil composition and partition of Fe forms were determined, and analysis of minerals by Scanning Electron Microscope, was performed on soil samples. Isotopic ratios (δ13C, δ15N) were also determined on soil and leaf samples. Soils showed significant spatial and temporal changes affecting both their properties (pH, Eh) and their composition (TOC, pyrite and Fe oxyhydroxide contents). Clear spatial changes were observed in redox potential, significantly affecting the concentrations of the different geochemical forms of Fe, particularly the concentrations of crystalline oxyhydroxydes and pyrite in one of the studied sites. In three of the study sites, pyrite crystals showed clear evidence of degradation associated with sandy soils. Finally, δ13C and N/C ratios in soils seem to suggest a mixed origin of organic matter.
ARTICLE | doi:10.20944/preprints201904.0054.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: CLNK; thalassemia; ferritin; iron overload
Online: 4 April 2019 (12:35:43 CEST)
Beta-thalassemia major (β-TM) is a severe form of thalassemia caused by mutations in the β-globin gene, resulting in partial or complete deficiency of β-globin chains. This deficiency results in oxidative stress, dyserythropoiesis, and chronic anemia. Cytokine dependent hematopoietic cell linker (CLNK) belongs to the adaptor protein family and has the capacity to interact with multiple signaling proteins thereby modulating signal transduction. The aim of the present study was to examine CLNK in sera of β-TM patients and examine its association with iron overload biomarkers. Sixty β-TM patients, aged 3–12 years old and undergoing blood transfusions, and 30 healthy control children were recruited and CLNK, ferritin and iron status parameters were measured. The results showed a significant increase (p < 0.001) in serum CLNK levels in β-TM patients as compared with normal controls. The increased levels of CLNK were significantly associated with increased ferritin levels. Increased CLNK levels in β-TM may be explained by reciprocal effects between immune signaling and immature erythrocytes, which, release soluble receptors and signaling molecules, including CLNK, in the blood.
ARTICLE | doi:10.20944/preprints201910.0107.v1
Subject: Engineering, Energy And Fuel Technology Keywords: hydrogen; methane pyrolysis; direct reduced iron; industrial decarbonization; iron and steel; electric arc furnace
Online: 9 October 2019 (11:33:17 CEST)
Reducing emissions from the iron and steel industry is essential to achieve the Paris climate goals. A new system to reduce the carbon footprint of steel production is proposed in this article by coupling hydrogen direct reduction of iron ore (H-DRI) and natural gas pyrolysis on liquid metal surface inside a bubble column reactor. If grid electricity from EU is used, the emissions would be 435 kg CO2/tls without considering methane leakage from the extraction, storage and transport of natural gas. Solid carbon, produced as a by-product of natural gas decomposition, finds applications in many industrial sectors, including as a replacement for coal in coke ovens. Specific energy consumption (SEC) of the proposed system is approximately 6.3 MWh per ton of liquid steel(tls). It is higher than other competing technologies, 3.48 MWh/tls for water electrolysis based DRI, and, 4.3-4.5 MWh/tls for natural gas based DRI and blast furnace-basic oxygen furnace (BF-BOF) respectively. Utilization of large quantities of natural gas, where the carbon remains unused, is the major reason for high SEC. Preliminary analysis of the system revealed that it has the potential to compete with existing technologies to produce CO2 free steel, if renewable electricity is used. Further studies on the kinetics of the bubble column reactor, H-DRI shaft furnace, design and sizing of components, along with building of industrial prototypes are required to improve the understanding of the system performance.
ARTICLE | doi:10.20944/preprints202311.0528.v1
Subject: Biology And Life Sciences, Food Science And Technology Keywords: Chitosan; thermosensitive hydrogel; iron deficiency; pig
Online: 8 November 2023 (16:12:08 CET)
Iron deficiency anemia (IDA) is a world health problem for humans and other mammals; affecting critical stages of development. Pigs have been used as an experimental model for the study and prevention of anemia because of physiological and metabolic similarities with humans. Iron dextran particles (IDP) are used for intramuscular (IM) IDA treatments in pigs, but are insufficient for prevention of anemia due to quick metabolization. Therefore, the objective of this study was to develop chitosan thermosensitive hydrogels (CTH) formulations and to study their potential as a mammalian parenteral iron dextran supplementation strategy. CTH were loaded with IDP at increasing iron concentrations (0.1, 0.2 and 0.4 g of theorical iron/g of chitosan) and characterized as an IM iron supplement. All the CTH-IDP formulations were thermosensitive and can be injected IM at ~4 °C, with a significant rise in viscosity between 25-37 °C. IDP content was physically trapped in the chitosan hydrophobic gel at 37 °C, without evidence of chemical bonding. We conclude that CTHs are a promising strategy for IM delivery strategy of IDP, and these results may be useful for future iron supplementation studies in pigs, humans and other mammals.
ARTICLE | doi:10.20944/preprints202305.2069.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: BPAN; WDR45; antioxidants; autophagy; iron accumulation
Online: 31 May 2023 (03:32:17 CEST)
Neurodegeneration with brain iron accumulation (NBIA) is a group of rare neurogenetic dis-orders frequently associated with iron accumulation in the basal nuclei of the brain. Among NBIA subtypes, β -propeller protein-associated neurodegeneration (BPAN) is associated with mutations in the autophagy gene WDR45. The aim of this study was to demonstrate autophagic defects and secondary pathological con-sequences in cellular models derived from two patient harboring WDR45 mutations. Both protein and mRNA expression levels of WDR45 were decreased in patient-derived fibro-blasts. In addition, the increase of LC3B upon treatments with autophagy inducers or inhibitors was lower in mutant cells compared to control cells, suggesting decreased autophagosome formation and impaired autophagic flux. Transmission electron microscopy (TEM) analysis showed mitochondrial vacuolization associated with accumulation of lipofuscin-like aggregates containing undegraded material. Autophagy dysregulation was also associated with iron ac-cumulation and lipid peroxidation. In addition, mutant fibroblasts showed altered mitochon-drial bioenergetics. Antioxidants such as pantothenate, vitamin E and α-lipoic prevented lipid peroxidation and iron accumulation. However, antioxidants were not able to correct the ex-pression levels of WDR45 neither the autophagy defect nor cell bioenergetics. Our study demonstrated that WDR45 mutations in BPAN cellular models impaired autophagy, iron metabolism and cell bioenergetics. Antioxidant partially improved cell physiopathology, however autophagy and cell bioenergetics remained affected.
ARTICLE | doi:10.20944/preprints202105.0283.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Wheat; Biofortification; Iron; Zinc; Rht genes
Online: 13 May 2021 (11:20:29 CEST)
Wheat (Triticum aestivum L.) being a staple food crop is an important nutritional source providing protein and minerals. It is important to fortify staple cereals like wheat with essential minerals to overcome the problems associated with malnutrition. The experiment was designed to evaluate the status of 11 micronutrients including grain iron (GFe) and zinc (GZn) in 62 wheat cultivars released between 1911 and 2016 in Pakistan. Field trials were conducted over two years and GFe and GZn were quantified by both inductively coupled plasma optical emission spectroscopy (ICP-OES) and energy dispersive X-ray fluorescence spectrophotometer (EDXRF). The GZn ranged from 18.4 to 40.8 mg/kg by ED-XRF and 23.7 to 38.8 mg/kg by ICP-OES. Similarly, GFe ranged from 24.8 to 44.1 mg/kg by ICP-OES and 26.8 to 36.6 mg/kg by EDEXR. The coefficient of correlation was higher for GZn (r=0.90), compared to GFe (r=0.68). Modern cultivars like Zincol-16 and AAS-2011 showed higher GFe and GZn along with improved yield components. Old wheat cultivars WL-711, C-518 and Pothowar-70 released before 1970 also exhibited higher value of GFe and GZn, however their agronomic performance was poor. Multivariate analysis using ten micronutrients (Al, Ca, Cu, K, Mg, Mn, Na and P) along with agronomic traits, and genome-wide SNP markers identified the potential cultivar with improved yield, biofortification trait and wider genetic diversity. Genetic gain analysis identified significant increase in grain yield (0.4% year-1), while there was negative gain for GFe (-0.11% year-1) and GZn (-0.15% year-1) over the span of 100 years. The Green Revolution Rht-B1 and Rht-D1 genes had strong association with plant height, and grain yield (GY), while semi-dwarfing alleles had negative effect on GFe and GZn contents. This study provided a valuable insight into biofortification status of wheat cultivars deployed historically in Pakistan and is a valuable source to initiate a breeding strategy for simultaneous improvement in wheat phenology and biofortification.
REVIEW | doi:10.20944/preprints202010.0447.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Iron homeostasis; Cancer; Prognostic; Diagnostic; Therapy
Online: 22 October 2020 (08:56:33 CEST)
Iron (Fe) is a trace element that plays essential roles in various biological processes such as DNA synthesis and repair, as well as cellular energy production, or oxygen transport, and it is currently widely recognized that iron homeostasis is dysregulated in many cancers. Indeed, several iron homeostasis proteins may be responsible for malignant tumor initiation, proliferation, and for metastatic spread of tumors. A large number of studies demonstrated the potential clinical value of turning these deregulated proteins as prognostic and/or predictive biomarkers of malignancy and /or response to anticancer treatments. Additionally, the iron addiction of cancer cells and the importance of iron in ferroptosis cell death signaling pathways prompted the development of therapeutic strategies against advanced stage or resistant cancers. In this review, we selected relevant and promising studies in the field of iron metabolism in cancer research and clinical oncology. Besides, we discuss some co-existing discrepant findings. We will also present and discuss the latest lines of research related to targeting iron, or its regulatory pathways, as potential promising anti-cancer strategies for human therapy. Iron chelators, such as deferoxamine or iron-oxide based nanoparticles, which are already tested in clinical trials, alone or in combination with chemotherapy will also be reported.
ARTICLE | doi:10.20944/preprints201909.0147.v1
Subject: Medicine And Pharmacology, Pathology And Pathobiology Keywords: iron; TIBC; ferritin; osmotic fragility; hypertension
Online: 15 September 2019 (03:10:09 CEST)
Background: Essential hypertension is a major public health associated with increase pressure on the vascular walls and red blood cells (RBCs). In the present work, osmotic fragility (OF) of RBCs was reexamined in the means of its correlation with two risk factor; iron status and lipid profile. Experimental: OF, iron status parameters, and lipid profile components were measured in 60 patients and compared with the results of 30 controls. Results: The results showed a significant increase in all iron indices of hypertensive patients in comparing with healthy control group except TIBC, UIBC, and transferrin concentrations, which decrease in these patients in comparing with control group. Serum TGs, total cholesterol, VLDLc, and LDLc were increased while there is no significant in serum HDLc in patients to comparing with control group. There is no significant change in OF between patients and controls where p=0.173. The iron status parameters and lipid profile components were dependent on sex and smoking state. Hemoglobin and PCV were correlated significantly with total cholesterol and LDLc. Transferrin saturation showed a positive correlation with cholesterol, LDLc, and TGs, but negatively correlated with HDLc. No significant correlation between all the measured parameters and OF in HT patients. There is a significant correlation between serum ferritin and systolic BP and between Hb and systolic BP. Conclusion: No significant effect on the OF in HT patients. HT patients have elevated level of iron parameters in comparing with controls. OD has no correlation with iron status parameters or with lipid profile components.
REVIEW | doi:10.20944/preprints202012.0583.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: sideroflexin; mitochondria; mitochondrial transporters; iron homeostasis; iron-sulfur cluster; heme biosynthesis; one-carbon metabolism; ferroptosis; ferritinophagy.
Online: 23 December 2020 (10:40:15 CET)
Sideroflexins (SLC56 family) are highly conserved multi-spanning transmembrane proteins inserted in the inner mitochondrial membrane in eukaryotes. Few data are available on their molecular function but, since their first description, they were thought to be metabolite transporters probably required for iron utilization inside the mitochondrion. Such as numerous mitochondrial transporters, sideroflexins remain poorly characterized. The prototypic member SFXN1 has been recently identified as the previously unknown mitochondrial transporter of serine. Nevertheless, pending questions on the molecular function of sideroflexins remain unsolved, especially their link with iron metabolism. Here, we review the current knowledge on sideroflexins, their presumed mitochondrial functions and the sparse - but growing - evidence linking sideroflexins to iron homeostasis and iron-sulfur cluster biogenesis. Since an imbalance in iron homeostasis can be detrimental at the cellular and organismal levels, we also investigate the relationship between sideroflexins, iron and physiological disorders. Investigating Sideroflexins’ functions constitutes an emerging research field of great interest and will certainly lead to main discoveries on mitochondrial physiopathology.
ARTICLE | doi:10.20944/preprints202007.0564.v1
Subject: Chemistry And Materials Science, Metals, Alloys And Metallurgy Keywords: history of metallurgy; co-fusion steelmaking; ancient China; microstructure evolution; simulation experiments; cast iron; wrought iron
Online: 23 July 2020 (12:49:21 CEST)
The study of co-fusion was one of the essential topics in the history of metallurgy in China. Simulation experiments had been an essential concept in the study of the co-fusion steelmaking process. This paper mainly studied the simulation experiments of co-fusion from two aspects: the replication of co-fusion swords by three different methods, and the micro-analysis of the co-fusion samples. The experimental results indicated that several co-fusion swords could be made by different processes, but the carbon content and surface hardness were quite different. During repeated forging welded, the microstructure of the samples transformed from laminated to homogenized, finally the steel with a uniform carbon content was obtained. It was challenging to find the characteristics of co-fusion from the homogenized samples. The results prompted people to rethink the microstructure characteristics of ancient co-fusion artifacts.
ARTICLE | doi:10.20944/preprints202102.0603.v1
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: ORR; PGM-free; iron; chitosan; biomass, acid electrolyte; iron-nitrogen-doped carbon; graphitization, site density, Fe-Nx
Online: 26 February 2021 (09:43:44 CET)
The development of platinum group metal-free (PGM-free) electrocatalysts derived from cheap and environmentally friendly biomasses for oxygen reduction reaction (ORR) is a topic of relevant interest, particularly from the point of view of sustainability. Fe-nitrogen-doped carbon materials (Fe-N-C) have attracted particular interest as alternative to Pt-based materials, due to the high activity and selectivity of Fe-Nx active sites, the high availability and good tolerance to poisoning. Recently, many studies focused on developing synthetic strategies, which could transform N-containing biomasses into N-doped carbons. In this paper chitosan was employed as a suitable N-containing biomass for preparing Fe-N-C catalyst in virtue of its high N content (7.1%) and unique chemical structure. Moreover, the major application of chitosan is based on its ability to strongly coordinate metal ions, a precondition for the formation of Fe-Nx active sites. The synthesis of Fe-N-C consists in a double step thermochemical conversion of a dried chitosan hydrogel. In acidic aqueous solution, the preparation of physical cross-linked hydrogel allows to obtain sophisticated organization, which assure an optimal mesoporosity before and after the pyrolysis. After the second thermal treatment at 900 °C, a highly graphitized material was obtained, which has been fully characterized in term of textural, morphological and chemical properties. RRDE technique was used for understanding the activity and the selectivity of the material versus the ORR in 0.5 M H2SO4 electrolyte. Special attention was put in the determination of the active site density according to nitrite electrochemical reduction measurements. It was clearly established that the catalytic activity expressed as half wave potential linearly scales with the number of Fe-Nx sites. It was also established that the addition of the iron precursor after the first pyrolysis step leads to an increased activity because of both an increased number of active sites and of a hierarchical structure, which improves the access to active sites. At the same time, the increased graphitization degree, and a reduced density of pyrrolic nitrogen groups are helpful to increase the selectivity toward the 4e- ORR pathway.
ARTICLE | doi:10.20944/preprints202310.1575.v1
Subject: Biology And Life Sciences, Agricultural Science And Agronomy Keywords: biofortification; chickpea; iron deficiency; Fe-EDDHA; fertilization
Online: 25 October 2023 (05:16:01 CEST)
Iron (Fe) deficiency specifically is the most common nutritional disorder due to insufficient absorbable Fe. Biofortification is a process of enriching the nutrient content of staple crops and is considered as a sustainable and cost-effective strategy to address micronutrient deficiency problems especially in the less developed countries. Chickpea (Cicer arietinum L.) is a staple food in many developing countries worldwide and is an excellent source of micronutrients. Biofortification of chickpea is a possible solution to address Fe deficiency problem. Chickpea biofortification experiment was conducted under field conditions to evaluate the effects of different doses of Fe fertilizer (0 kg ha-1,10 kg ha-1 and 30 kg ha-1 of Fe-EDDHA) on Fe content in seeds of 18 chickpea cultivars. The experiment was designed as a factorial combination of 18 chickpea cultivars and 3 different doses in a randomized complete block design with 4 replications at two locations in Saskatchewan in 2015 and 2016. Fe concentration in seeds across 18 different chickpea cultivars increased with Fe fertilization. Fe concentration in X05TH20-2 and CDC Frontier cultivars increased from 57 ppm to 59 ppm and 56 ppm to 58 ppm, respectively, after adding Fe fertilizer in both location in 2015 and 2016.
ARTICLE | doi:10.20944/preprints202310.1242.v1
Subject: Public Health And Healthcare, Public Health And Health Services Keywords: dietary iron; pregnancy; mother; Neonate; gut microbiota
Online: 19 October 2023 (10:34:35 CEST)
The aim of the study was to investigate the association between maternal dietary iron intake during pregnancy and the gut microbiota characteristics of both the mother and neonate in a well-characterized cohort. A total of 95 mother-neonate dyads were included in our study, with basic information collected through questionnaires. A semi-quantitative Food Frequency Questionnaire (FFQ) was used to assess maternal dietary intake during pregnancy, and maternal dietary iron intake was categorized into <20 mg/d and ≥20 mg/d groups. Fecal samples were collected from the mother in the third trimester and the neonate, allowing for assessment of the community profile and diversity of gut microbiota via 16S rRNA amplicon sequencing. Then, a comparison between different maternal dietary iron intake groups was conducted, adjusting for delivery mode (VD, vaginal delivery; CS, cesarean section) and other potential confounding factors. No significant differences in community profile and diversity were observed for the maternal gut microbiota in different dietary iron intake groups. In neonate fecal samples, the Shannon (P = 0.044) and Simpson (P = 0.010) diversity indices of the gut microbiota were higher in the maternal dietary iron intake ≥20 mg/d group, while Simpson diversity presented the same tendency in vaginal delivery (P = 0.041) after stratification. The relative abundance of the core genus Bifidobacterium showed a significant difference between groups (4.69 [1.19–12.77] vs. 13.98 [3.44–27.28]; P = 0.044). The abundance of Lactobacillus was different in the ≥20 mg/d group under both delivery modes (VD: beta = 2.9, w = 4.13; CS: beta = 2.77, w = 3.8). Our findings suggest that adequate dietary iron intake during pregnancy may promote beneficial bacterial colonization and increase the biodiversity of the neonate gut microbiota.
ARTICLE | doi:10.20944/preprints202310.0228.v1
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: iron; Speciation; Voltammetry; Water; Antimony-Bismuth Film
Online: 4 October 2023 (10:24:04 CEST)
Iron, a crucial element in our environment, plays a vital role in numerous natural processes. Understanding the presence and concentration of iron in the environment is very important, as it impacts various aspects of our planet’s health. On-site detection and speciation of iron are significant for several reasons. In this context, the present work aims to evaluate the applicability of voltammetry for on-site determination of iron and its possible speciation using a portable voltammetric analyzer. Voltammetry offers the advantage of convenience and cost-effectiveness. For iron (III) determination a modification of a glassy carbon electrode (GCE) with an antimony-bismuth film (SbBiFE) using acetate buffer (pH=4) as supporting electrolyte was used. The technique adopted was Square Wave Adsoptive Cathodic Stripping Voltammetry (SW-AdCSV) and we used 1-(2-piridylazo)-2-naphthol (PAN) as iron (III) ligand. Linearity, repeatability, detection limit and accuracy were determined using synthetic solutions, then a Standard Reference Material (SRM) 1643f - Trace Elements in Water was used for validation measurements in real matrix. The procedure was finally applied to real samples (tap, lake and sea water) and the results obtained were compared by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). The results obtained demonstrated the excellent applicability of the proposed on-site voltammetric procedure for the determination of iron and its speciation in water.
REVIEW | doi:10.20944/preprints202201.0026.v1
Subject: Engineering, Energy And Fuel Technology Keywords: Anaerobic digestion; iron additives; biogas; catalyst; bioenergy
Online: 5 January 2022 (10:23:53 CET)
The world is facing a serious energy crisis and environmental pollution problems due to a sharp increase in the world population. Bioenergy is an eminent solution to these problems. Anaerobic digestion is a green energy technology used worldwide for the conversion of organic waste to biogas. It is reported that organic wastes are hard to digest and need some technical improvement in the anaerobic digestion process to improve biogas yield. Iron-based additives, due to their electron acceptance and donation capabilities, have been emphasized as being exceptional in improving anaerobic digestion process efficiency amongst all other enhancement options. This study reviews the major available types of iron-based additives, their characteristics, and their preparation methods. The preferred iron-based additive that has a significant effect on the enhancement of biogas yield is also discussed. The use of iron-based additives in the anaerobic digestion process with varying dosages and their impact on the biogas generation rate is also being studied. Substrates, operating parameters, and types of anaerobic digesters used in recent studies while researching the effects of iron-based additives are also part of this review. Lastly, this study also confirms that iron-based additives have a significant effect on the reduction rate of the volatile suspended solids, methane content, biogas yield, and volatile fatty acids.
ARTICLE | doi:10.20944/preprints202001.0177.v1
Subject: Chemistry And Materials Science, Metals, Alloys And Metallurgy Keywords: copper smelting slag; pig iron; fayalite; recovery
Online: 17 January 2020 (04:32:53 CET)
Copper smelting slag is a solution of molten oxides created during the copper smelting and refining process, and about 1.5 million tons of copper slag is generated annually in Korea. Oxides in copper smelting slag include ferrous (FeO), ferric oxide (Fe2O3), silica (SiO2 from flux), alumina (AI2O3), calcia (CaO) and magnesia (MgO). Main oxides in copper slag, which iron oxide and silica, exist in the form of fayalite (2FeO·SiO2). Since the copper smelting slag contains high content of iron, and copper and zinc. Common applications of copper smelting slag are the value added products such as abrasive tools, roofing granules, road-base construction, railroad ballast, fine aggregate in concrete, etc., as well as the some studies have attempted to recover metal values from copper slag. This research was intended to recovery Fe-Cu alloy, raw material of zinc and produce reformed slag like a blast furnace slag for blast furnace slag cement from copper slag. As a results, it was confirmed that reduction smelting by carbon at temperatures above 1400°С is possible to recover pig iron containing copper from copper smelting slag, and CaO additives in the reduction smelting assist to reduce iron oxide in the fayalite and change the chemical and mineralogical composition of the slag. Copper oxide in the slag can be easily reduced and dissolved in the molten pig iron, and zinc oxide is also reduced to a volatile zinc, which is removed from the furnace as the fumes, by carbon during reduction process. When CaO addition is above 5wt.%, acid slag has been completely transformed to calcium silicate slag and observed like blast furnace slag.
ARTICLE | doi:10.20944/preprints201912.0356.v1
Subject: Medicine And Pharmacology, Pediatrics, Perinatology And Child Health Keywords: Beta-thalassemia, Erythroferrone, Ferritin, Hepcidin, Iron overload
Online: 26 December 2019 (12:37:36 CET)
Beta thalassemia major (β-TM) disorder characterized by the lack, or severe reduction in the production of hemoglobin β-globin chains. The standard protocol for the management of β-TM is blood transfusion and iron chelation therapy to reduce the iron overload state. The present study aimed to investigate the relationships between two iron regulatory hormones, hepcidin (HEPC) and erythroferrone (ERFE) levels and iron status parameters (ISPs) in Iraqi patients with β-TM. ISPs and hormones were measured in sixty patients and compared with thirty healthy controls. The results indicated significant changes in different iron status parameters, while ferritin (FRT) with the ~11 fold increase showed the most change. Significant reduction in HEPC and increase in ERFE levels were detected in patients as compared to the control group, while no direct correlation was identified with the other measured ISPs. Receiver operating characteristic (ROC) analysis showed that the z-score of the composite of ERFE+FRT has a full diagnostic ability for β-TM. In conclusion, our finding indicated the correlation between different ISPs, FRT as the leading predictor of iron overload and tow main iron regulatory hormones.
ARTICLE | doi:10.20944/preprints201903.0092.v1
Subject: Biology And Life Sciences, Agricultural Science And Agronomy Keywords: Biofortification, Pearl millet, Malnutrition, Iron, Zinc, Market.
Online: 7 March 2019 (12:08:24 CET)
Pearl millet is an important food crop in the arid and semi-arid tropical regions of Africa and Asia. These regions are home to millions of poor smallholder’s households living in harsh agro ecology and reported higher prevalence of malnutrition. Such poor households have few options in terms of food crops, besides the limited markets. Indeed, pearl millet is one of the food crops they continue to grow for their food and nutritional security. Pearl millet is important sources of dietary carbohydrates, energy, protein, and important minerals such as calcium, iron and zinc. Considering inherent high nutritional values and climate resilient nature (drought and heat), demand for pearl millet as food, beside valued for its Stover as a source of livestock fodder, is projected to grow strongly in Asia (India) and Africa (West and Central Africa). Iron (cause anemia) and zinc (cause stunting) deficiencies are widespread and serious public health problems worldwide, including India and Africa. Biofortification is a cost-effective and sustainable agricultural strategy to address this problem. Research on pearl millet has shown that large genetic variability (30-140 mg/kg Fe and 20-90 mg/kg Zn) available in this crop can be effectively utilized to develop high-yielding cultivars with high iron and zinc densities. Both Open –pollinated varieties (Dhanshakti and Chakti) and hybrids (ICMH 1202, ICMH 1203 and ICMH 1301) of pearl millet with high grain yield (>3.5 tons/ha in hybrids) and high levels of iron (70-75 mg/kg) and zinc (35-40 mg/kg) densities have been developed and released. Currently, India growing >70,000 ha of biofortified pearl millet, besides more pipeline hybrids and varieties are under various stage of testing at the national (India) and international (west Africa) trials for possible release. Genomic tools will be an integral part of breeding program particularly for nutritional traits to use diagnostic markers and genomic selection. Clinical studies showed that 200g grains from biofortified cultivar would provide bioavailable Fe to meet full recommended daily allowance (RDA) in children, adult men and 80% of the RDA in women. Till today, no markets to promote biofortified cultivars/grains/products as no incentive price and such products aims to address food and nutritional security challenges simultaneously. The demand is likely to increase only after investment and integration into modern public distribution system, nutritional intervention schemes, private seed and food companies with strong mainstreaming nutritional policies. In the non-traditional regions, this will contribute to livestock and poultry feed industry as spill-over benefits to improve nutrition.
REVIEW | doi:10.20944/preprints201809.0148.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: NCOA4, ferritinophagy, iron homeostasis, erythropoiesis, ferroptosis, cancer
Online: 9 September 2018 (16:13:18 CEST)
Nuclear receptor coactivator 4 (NCOA4) is a selective cargo receptor that mediates the autophagic degradation of ferritin (“ferritinophagy”), the cytosolic iron storage complex. NCOA4-mediated ferritinophagy maintains intracellular iron homeostasis by facilitating ferritin iron storage or release according to demand. Ferritinophagy is involved in iron-dependent physiological processes such as erythropoiesis, where NCOA4 mediates ferritin iron release for mitochondrial heme synthesis. Recently, ferritinophagy has been shown to regulate ferroptosis, a newly described form of iron-dependent cell death mediated by excess lipid peroxidation. Dysregulation of iron metabolism and ferroptosis have been described in neurodegeneration, cancer, and infection, but little is known about the role of ferritinophagy in the pathogenesis of these diseases. Here, we will review the biochemical regulation of NCOA4, its contribution to physiological processes and its role in disease. Finally, we will discuss the potential of activating or inhibiting ferritinophagy and ferroptosis for therapeutic purposes.
ARTICLE | doi:10.20944/preprints201608.0179.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: bioleaching; molecuar analysis; bacteria; sequencing; iron ore
Online: 19 August 2016 (09:23:04 CEST)
One consequence of the global technological advancement in conventional metallurgy is the fast depletion rate of valuable minerals, which are also becoming increasingly difficult to find in pure and economically viable forms. This has spurred more interest in technologies that investigate ability of different microorganisms to mobilize valuable metals from their ores via diverse metabolic processes. This study was carried out therefore to isolate, identify and characterize iron solubilizing bacteria from Iron stones of Agbaja iron ore mining site of Kogi State, Nigeria. Crushed samples in the range of 0.25µm and 0.75µm particle sizes were cultured in a modified 9k media to facilitate bacterial growth and pure cultures were then isolated and sub-cultured for further bioleaching studies. Morphological and biochemical analysis suggests that some of the bacteria identified are members of Acidithiobacillus spp, Pseudomonas spp, and Leptospirillum spp. Studies conducted on pure cultures and mixed consortium of the identified organisms shows that a mixture of the three organisms leached iron ore to about 96.16%. Also results of growth pattern due to bacteria countafter 24-72hours of incubation ranged between 0.1×103 cfu/ml and 12.3 ×103 cfu/ml for Acidithiobacillus spp. The need to explore the molecular characteristics of these organisms with a view to generating more information on the quality/quantity of their DNA for future cloning activities was also investigated in this work. DNA was extracted using zymo fungal/bacterial extraction mini prep kit TM (cat #6001) and subsequently subjected to 1% agarose gel electrophoresis. Visible bands were obtained with Alpha Innotech Gel Documentation Machine. DNA amplification was carried out using a pettier based thermo cycler PCR machine and electrophoresed on 1.5% agarose gel. Results of the PCR shows a visible band corresponding to 1.5kbp using this primer 27F (51-GAGTTTGATCCTGGCTCAG-31) and 1492R (51-GGTTACCTTGTTACGACT-31). DNA purity check shows two of the bacteria possess very good qualities for sequencing for further molecular analysis.
REVIEW | doi:10.20944/preprints202310.1423.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: Oxidative stress; Ferroptosis; Iron; Cell death; Lipid peroxidation
Online: 23 October 2023 (09:42:29 CEST)
Ferroptosis is a recent form of non-apoptotic cell death, which occurs due to imbalance of iron homeostasis (iron overload). Oxidative stress due to the impairment of the antioxidant system is a major pathophysiology during ferroptosis, which eventually results in lipid peroxidation. The cellular and physiological biomarker of ferroptotic cell death includes major alteration in the glutathione peroxidase 4 (GPX4) antioxidant system and lipid peroxidation induced loss of plasma membrane integrity. This review elaborates the mechanism of oxidative stress which triggers ferroptosis.
INTERESTING IMAGES | doi:10.20944/preprints202310.0924.v1
Subject: Medicine And Pharmacology, Clinical Medicine Keywords: bone scan; 99mTc-HDP; cardiac amyloidosis; iron overload
Online: 16 October 2023 (08:19:35 CEST)
In this presented case, a 77 years old woman suffering from ongoing knee pain underwent a bone scan using 99mTc-hydroxydiphosphonate (HDP) in suspicious for bone infection. An incidental finding from this scan revealed diffuse cardiac uptake, necessitating further diagnostic procedures to exclude the possibility of cardiac amyloidosis. In the subsequent 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD) scan and SPECT images, no perceptible cardiac uptake was observed at all. Upon retrospective review of the patient’s medical records, she had received 1000mg of ferric carboxymaltose for iron-deficient anemia, the day before the 99mTc-HDP bone scan. Therefore, it is assumed that the diffuse and temporary cardiac activity was due to the transient iron overload. We present and share this bone scan images in order to avoid possible future misinterpretation of cardiac amyloidosis.
ARTICLE | doi:10.20944/preprints202309.2085.v1
Subject: Engineering, Mechanical Engineering Keywords: strain rate sensitivity; G18NiCrMo3-6; cast iron plasticity
Online: 29 September 2023 (08:16:57 CEST)
This contribution was devoted to unveil the strain rate sensitivity (SRS) of G18NiCrMo3-6 cast steel in tension/compression asymmetry. For that purpose, detailed mechanical characterization tests were conducted providing a process window covering quasi-static and medium strain rate regimes (0.001, 0.1, 10 [ s¯¹]) in tension and compression states. By means of this experimental ef-fort, the SRS of the material could be extracted by a function of strain and strain rate which ena-bling to create a mathematical expression to easily be implemented as a state variable for constitu-tive material modeling. Finally, a pressure and rate dependent constitutive material model on the basis of Cocks'89 yield locus definition was created by a subroutine (UMAT) file and the material parameters were verified with respect to the experimental data. The UMAT file also takes into account the tension/compression asymmetry in yielding to handle the effect of porous media plas-ticity concept. The predictions of the proposed material model are quite in line with the experi-mental outputs.
COMMUNICATION | doi:10.20944/preprints202306.0701.v1
Subject: Medicine And Pharmacology, Urology And Nephrology Keywords: Iron isomaltoside; NF-kappaBeta; dehydroxymethyepoxyquinmicin (DHMEQ); mesothelial cells
Online: 9 June 2023 (10:37:47 CEST)
Background. Intravenous iron therapy is used in treatment of anemia in uremic pa-tients. In patients treated with peritoneal dialysis iv. infused iron diffuses into the peritoneal cavity and may cause injury to the mesothelial cell. Methods. We studied effect of Iron Isomaltoside (IIS) in presence of NF-κβ inhibitor dehydroxymethyepoxyquinmicin (DHMEQ) on function of the peritoneal mesothelial cells. Experiments were performed on human peritoneal mesothelial cells in in vitro culture ex-posed to IIS 15 ug/dL ± DHMEQ 1 ug/mL. Intracellular oxidative stress, secretory activity and collagen synthesis in the cells were studied. Results. IIS induced oxidative stress in the mesothelial cells and that effect was weaker in presence of DHMEQ (-52%,p<0.001). In cells exposed to IIS increased expression of genes for IL6 (+74%,p<0.001), PAI-1 (+43%, p<0.01) and TGFβ (+53%,p<0.001) was observed and reduced for tPA (-36%,p<0.01). In presence of IIS increased secretion of IL6 (+56%, p<0.001), TGFβ (+49%,p<0.001) and PAI-1 (+51%, p<0.001) was observed whereas secretion of tPA was reduced (-25%, p0.001). DHMEQ reduced changes in genes and secre-tory activity caused by IIS. In presence of IIS synthesis of collagen in mesothelial cells was increased (+45%,p<0.001) and that effect was weaker (-25% vs. IIS, p<0001) when simulta-neously DHMEQ was used. Discussion. IIS induces proinflammatory changes in mesothelial cells, deteriorates their fibrinolytic activity and stimulates synthesis of collagen. All these effects are reduced when simultaneously NF-κβ inhibitor – DHMEQ is used.
ARTICLE | doi:10.20944/preprints202305.2018.v1
Subject: Engineering, Mechanical Engineering Keywords: nitriding; iron nitride; wear; corrosion; tribocorrosion; mild steel
Online: 29 May 2023 (13:51:50 CEST)
Nitriding has long been used to engineer the surfaces of engineering steels to improve their surface and subsurface properties. The role of the surface compound layer (’-Fe4N and/or -Fe2-3N) in improving the tribological and corrosion resistant properties of nitrided steels has been established. However, there have been very few studies on the response of the compound layer to tribocorrosion in corrosive environments. In this work, the tribocorrosion behaviour of a 5 m thick ’-Fe4N nitride layer produced on mild steel (MS) by plasma nitriding has been studied in a NaCl containing solution under various electrochemical conditions. The results show that at a cathodic potential, where mechanical wear is predominant, the total material removal (TMR) from the ’-Fe4N layer is 37% smaller than that from the untreated MS, and at open circuit potential, TMR from the layer is 35% smaller than that from the untreated MS, while at an anodic potential, the ’-Fe4N layer can reduce TMR from mild steel by 87%. The beneficial effect of the ’-Fe4N nitride layer in improving the tribocorrosion behaviour of mild steel is derived from its high hardness and good corrosion resistance in the test solution and its ability to resist both mechanical wear and chemical wear.
ARTICLE | doi:10.20944/preprints202305.1978.v1
Subject: Chemistry And Materials Science, Inorganic And Nuclear Chemistry Keywords: crystal structure; iron; pyridine; dicyanamide; quantum chemistry; magnetism
Online: 29 May 2023 (05:29:43 CEST)
Fe[C5H5N]2[N(CN)2]2 (1) was synthesized from a reaction of stoichiometric amounts of NaN(CN)2 and FeCl2·4 H2O in a methanol/pyridine solution. Single-crystal and powder diffraction show that 1 crystallizes in the monoclinic space group I2/m (no. 12), different from Mn[C5H5N]2[N(CN)2]2 (P21/c, no. 14) due to tilted pyridine rings, with a = 7.453(7) Å, b = 13.167(13) Å, c = 8.522(6) Å, β = 114.98(6)° and Z = 2. ATR-IR, AAS, and CHN measurements confirm the presence of dicyanamide and pyridine. Thermogravimetric analysis shows that π-stacking interactions of the pyridine rings play an important role in structural stabilization. Based on DFT-optimized structures, a chemical bonding analysis was performed using a local-orbital framework by projection from a plane-wave basis. The resulting bond orders and atomic charges are in good agreement with the expectations based on the structure analysis. SQUID magnetic susceptibility measurements show a high-spin state FeII compound with predominantly antiferromagnetic exchange interactions at lower temperatures.
ARTICLE | doi:10.20944/preprints202204.0132.v2
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: SLNB; SPIO; ALND; LS; superparamagnetic iron oxide nanoparticles
Online: 23 May 2023 (05:26:30 CEST)
Abstract: (1) Background: Sentinel lymph node biopsy assumes importance in the search for metastases, especially in patients with malignant breast disease. Our study approaches the new techniques to prevent complications such as possible postoperative seroma formation, pain or hypoesthesia of the axillary cord and medial arm surface, as well as motor deficits in a preventive manner to avoid disabling outcomes and presents initial data from its experience with the sentinel lymph node biopsy technique. (2) Methods: There are mainly two radioactive tracer detection techniques and a new technique using a radiotracer called Sentimag-magtrace. The positive lymph node is located and removed to perform histologic analysis. In our study, we evaluate 100 patients who underwent breast cancer surgery (3) Results: our experience allowed us to calculate the identification rate with the different methods of sentinel lymph nodes by radioactive tracer 88.9 % vs magnetic tracer technology (Sentimag) 89.5%. (4) Conclusions: Thus, this technique avoids radiation exposure for both patients and health care providers, as well as reducing costs and time.
ARTICLE | doi:10.20944/preprints202305.0444.v1
Subject: Environmental And Earth Sciences, Soil Science Keywords: soil indicators; vegetation indicators; iron mining; ecological restoration
Online: 8 May 2023 (04:45:53 CEST)
Many ecosystems are being severely degraded, leading the United Nations to deem 2021-2030 as the Decade on Ecosystem Restoration. To be successful, this effort requires robust monitoring tools to assess land reclamation practices. Our study aimed to evaluate the quality of recovery efforts in mined areas by developing a Recovery Quality Index (RQI) based on soil and vegetation indicators. Using the heavily mined Iron Quadrangle region of Brazil as an example, we selected four local, undisturbed reference areas as restoration goals: Atlantic Forest (AF); ferruginous rupestrian grassland with dense vegetation (FRGD); ferruginous rupestrian grassland with sparse vegetation (FRGS); and quartzite rupestrian grassland (QRG). We also selected four areas that were directly or indirectly affected by mining, including an environmental compensation area set aside 5 years prior to the study (COMP-5), two sterile piles that had undergone recovery for 15 and 20 years (SP-20 and SP-15), and a cave area with 15 years of recovery (CAVE-15). The four recovery areas were grouped together with each individual reference area (making four combinations of sites), and measurements of 2 vegetation parameters and 34 soil attributes were used in a Principal Component Analysis (PCA) for each grouping. We determined the RQI for each group by summing weighted PCA scores for responsive indicators. Vegetative parameters had the lowest RQI weights in all four groups. Soil physical indicators tended to be the most important, except in AF, where chemical indicators were most relevant. RQI values were also lowest when AF was used as the reference, showing that the forest was a unique ecosystem, and the CAVE-15 site had lower RQI scores than the other restored sites, indicating the high degree of disturbance that occurred in that low-lying area. The SP-20 site tended to have higher RQI values than the SP-15, and similar values to the less disturbed COMP-5 areas, potentially indicating greater recovery of native soil properties during the longer recovery period. This RQI-based approach has excellent potential for robust assessment of the recovery of areas degraded by mining and can support decision-making during monitoring.
ARTICLE | doi:10.20944/preprints202301.0097.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: mitochondria; iron transporters; MIT; developmental defects; RNA-seq
Online: 5 January 2023 (03:42:32 CET)
Iron is the most abundant micronutrient in plant mitochondria and it has a crucial role in biochemical reactions involving electron transfer. It has been described in Oryza sativa that Mitochondrial Iron Transporter (MIT) is an essential gene and that knockdown mutant rice plants have a decreased amount of iron in mitochondria, strongly suggesting that OsMIT is involved in mitochondrial iron uptake. In Arabidopsis thaliana, two genes encode MIT homologues. In this study, we analyzed different AtMIT1 and AtMIT2 mutant alleles, confirming that individually AtMIT1 nor AtMIT2 genes are essential. When we generated crosses between Atmit1 and Atmit2 alleles we were able to isolate homozygous double mutant plants. Interestingly, homozygous double mutant plants were obtained only when mutant alleles of Atmit2 with the T-DNA insertion in the intron region were used for crossings, and in these cases a correctly spliced AtMIT2 mRNA was generated, although at a low level. Atmit1 Atmit2 double homozygous mutant plants, which were knockout for AtMIT1 and knockdown for AtMIT2, were grown and chacterised in iron sufficient conditions. Pleiotropic developmental defects were observed including abnormal seeds, increased number of cotyledons, slow growth rate, pinoid stems, defects in flower structures and reduced seed set. We observed a possible phenomenon of T-DNA suppression in the next generation of Atmit1 Atmit2 double homozygous mutant plants, correlating with an increased splicing of the AtMIT2 intron containing the T-DNA. Molecular analysis of gene expression markers for mitochondrial and oxidative stress showed that Atmit1 Atmit2 double homozygous mutant plants express a degree of mitochondrial perturbation. A RNA-Seq study was performed and we could identify more than 760 genes differentially expressed in Atmit1 Atmit2, including genes involved in iron transport, coumarin metabolism, and hormones metabolism, transport and signaling. Our data suggest that some of the phenotypes observed in Atmit1 Atmit2 double homozygous mutant plants are mediated by defects in auxin homeostasis.
ARTICLE | doi:10.20944/preprints202205.0309.v1
Subject: Environmental And Earth Sciences, Environmental Science Keywords: steel shot; iron; soil; environmental risk; shooting activity
Online: 23 May 2022 (12:28:40 CEST)
This study is follow-up of the steel shot transformation under the influence of environmental factors research (Lisin et al., 2022) and is the initial stage of investigating the iron behavior in soils during steel shot corrosion under a number of factors: the metallic lead in soils, atmospheric precipitation, excess organic matter. The results obtained show that corrosion of steel ammunition is a continuous process, including the formation of a poorly soluble rust crust on the surface of the steel and the mineralization of the metal until it is destroyed. As a result, the metal transformed into rust form, is a constant source of iron ions and dispersed rust particles migrating in soil waters and accumulating in soils. In addition, the aggregation of corrosion products of steel ammunition is the cause of a change in physical and mechanical properties of soils, which leads to a violation of the air and water migration regime of soils and an increase in surface runoff from the territories of shooting activity. The highest environmental risks are observed when steel ammunition is used on shooting areas where metallic lead intensifies steel shot corrosion rate, while the deposited steel shot activates the deterioration of previously encapsulated metal and — if steel and lead ammunition are used at the same time — slows down the encapsulation of newly deposited metallic lead, which catalyses the accumulation and migration of lead in environmental components.
ARTICLE | doi:10.20944/preprints202105.0413.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Zinc; vitamin D; iron; Gripes; COVID-19; Anemia
Online: 18 May 2021 (10:34:15 CEST)
Abstract: COVID-19 in 2020 brought challenges to the Brazilian public health system with an emerging virus with respiratory contagion called SARS-CoV-2. There are few studies in Brazil and in some countries, on the increased incidence of certain viral respiratory infections, includ-ing H1N1 and coronavirus and their association with low levels of vitamin D, zinc and iron. The aim of this study was to demonstrate that the deficit of vitamin D, zinc and iron has an impact on the infectious process of patients with COVID-19 and to establish new forms of prevention for the worsening of COVID-19 in the human body. Data were collected from medical records and test results from patients being followed up during the treatment period for COVID-19. Patients with low blood levels of vitamin D, zinc and iron during the treatment period of COVID-19 had a higher percentage of worsening and complications requiring hospitalization in intensive care beds. The ingestion of vitamin D, zinc and iron in the treatment period of patients with COVID-19 in addition to being an immunological protector against SARS-CoV-2 and alleviating the process of worsening the disease can also act as a biomarker in cases of this disease.
ARTICLE | doi:10.20944/preprints202012.0180.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Chronic diseases; iron deficiency; haemoglobin; anaemia; aminoacids; rehabilitation
Online: 8 December 2020 (06:58:25 CET)
Chronic diseases are characterised by cell’s autophagy and proteins disarrangement resulting in sarcopenia, hypoalbuminemia and hypo-haemoglobinaemia. Hypo-haemoglobinaemia couses worse prognosis independentely of the principal disease. Currently, the cornerstone of therapy of anaemia is iron supplementation, with or without erythropoietin for the stimulation of hematopoiesis. However, treatment strategies should incorporate the addition of heme, the principal biochemical constituent of haemoglobin. Heme synthesis follows a complex biochemical pathway. The limiting step of heme synthesis is D-ALA availability which, for its synthesis, requires Glycine and Succinil-CoA. Consequently, treatment of anaemia should not be based only on iron availability, but also on the availability of the molecules fundamental for heme synthesis. Therefore, an adequate clinical therapeutic strategy should integrate the standard iron infusion and the supply of essential amino acids and vitamins involved in the heme synthesis. We report preliminary data in selected elderly anaemic patients with congestive heart failure (CHF) and catabolic disarrangement, who, in addition to standard iron therapy, received personalized therapy with essential-AAs and vitamins involved in the maintenance of heme. Notably, such individualized therapy resulted in a significant increase in the serum concentration of haemoglobin after 30 days of treatment compared to standard iron therapy.
ARTICLE | doi:10.20944/preprints202008.0708.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: streptococcus suis; transcriptome; ferrous iron; cobalt; RNA sequencing
Online: 31 August 2020 (09:51:43 CEST)
Streptococcus suis is a zoonotic pathogen causing serious infections in both swine and humans. Although metals are essential for life, excess amounts of metals they are toxic to bacteria. when accumulated in excess amounts. Except for zinc, Transcriptome-level data of the mechanisms for resistance to metal-induced toxicity in S. suis are available for no metals other than zinc. have not been investigated from the transcriptome level in S. suis. Herein, we explored the transcriptome-level changes of in S. suis in response to ferrous iron and cobalt toxicity by RNA sequencing. Many A lot of genes were differentially expressed in the presence of excess ferrous iron and cobalt. Most of the genes in response to cobalt toxicity showed the same expression trends as those were expressed in the same trend in response to ferrous iron toxicity. qRT-PCR analysis of the selected genes confirmed the accuracy of RNA sequencing results. Bioinformatics analysis of the differentially expressed genes indicated that ferrous iron and cobalt have similar impacts effects on the cellular processes of S. suis. Treatment with ferrous Ferrous iron treatment resulted in down-regulation of several oxidative stress tolerance-related genes involved in oxidative stress tolerance and up-regulation of the genes in an amino acid ABC transporter operon. Expression of the several genes in the arginine deiminase system was down-regulated in the presence of after ferrous iron and cobalt treatment. Collectively, our results suggested that S. suis alters the expression of a lot of multiple genes to respond to ferrous iron and cobalt toxicity.
ARTICLE | doi:10.20944/preprints202005.0185.v1
Subject: Chemistry And Materials Science, Materials Science And Technology Keywords: severe plastic deformation; iron hardness; micro/nano-structure
Online: 11 May 2020 (03:33:40 CEST)
The evolution of metals micro/nano-structure upon severe plastic deformation (SPD) is still far to be theoretically explained, while experimental datasets are persistently growing for several decades. Major problem associated with understanding of SPD is related to a fact that the latter is a synergetic product of several competing physical effects which alter the material micro/nano-structure. In attempt to find deformational boundaries, where predominantly one mechanism determines the micro/nano-structure, in this paper we propose a continuous piecewise model for the analysis of experiments on material hardness vs strain of SPD processed materials. The novelty of this approach lies in its ability to find, as free-fitting parameters, the strain breakpoints which separate different micro/nano-structure modes generated upon SPD process. The model is applied to analyse experimental data for polycrystalline samples of pure iron and two distinctive strain breakpoints are revealed with good accuracies. This finding is in a good agreement with our earlier results on TEM microscopy studies on pure iron polycrystals after SPD treatment.
ARTICLE | doi:10.20944/preprints202001.0178.v1
Subject: Biology And Life Sciences, Horticulture Keywords: blue light; calcium; iron; magnesium; potassium; red light
Online: 17 January 2020 (04:44:20 CET)
The current study investigated the impacts of light quality and different levels of fertility on mineral nutrient concentrations in shoot and root tissues of Chinese kale (Brassica oleracea var. alboglabra). ‘Green Lance’ Chinese kale were grown under: 1) fluorescent/incandescent light; 2) 10% blue (447 ± 5 nm) / 90% red (627 ± 5 nm) LED light; 3) 20% blue / 80% red LED light; and 4) 40% blue / 60% red LED light as sole-source lighting at two different levels of fertility. All plants were harvested 30 d after seeding, and shoot and root tissues were analyzed for mineral nutrients. Lighting and fertility interacted to influence kale shoot and root mineral nutrient concentrations. Results indicate sole-source LED lighting used in production can impact mineral nutritional values of baby leafy greens now popular for the packaged market.
ARTICLE | doi:10.20944/preprints202310.1356.v1
Subject: Chemistry And Materials Science, Inorganic And Nuclear Chemistry Keywords: crystal structures; cyclopentadienyl complexes; half-sandwich complexes; halides; iron
Online: 20 October 2023 (12:18:47 CEST)
Stable half-sandwich iron(II) dihalido complexes of the type [Fe(5-Cp’)X2] are extremely scarce, being limited to congeners containing the bulky C5H2-1,2,4-tBu3 ligand. We have extended this to homologues [Fe(5-Cp*)X2] (X = Cl – I) containing the particularly popular C5Me5 (Cp*) ligand. Corresponding ionic compounds ER4[Fe(5-Cp*)X2] are easily accessible from FeX2, MCp* (M = Li, K) and a suitable halide source R4EX (E = N, P) in THF. The new compounds NnPr4[Fe(5-Cp*)X2] (X = Cl, Br), NnPr4[Fe(5-Cp*)BrCl] and PPh4[Fe(5-Cp*)X2] (X = Cl, Br, I) have been structurally characterised by single-crystal X-ray diffraction. NnPr4[Fe(5-Cp*)Cl2] reacts readily with CO to afford [Fe(5-Cp*)Cl(CO)2], indicating the synthetic potential of ER4[Fe(5-Cp*)X2] in FeCp* half-sandwich chemistry.
ARTICLE | doi:10.20944/preprints202309.1075.v1
Subject: Environmental And Earth Sciences, Soil Science Keywords: arbuscular mycorrhizal fungi; iron toxicity soil; non-Host plant
Online: 18 September 2023 (02:45:51 CEST)
Brassicaceae are well known as non-arbuscular mycorrhizal (AM) host plants. This study was aimed to examine effects of two Brassica; cabbage (Brassica oleracea L. cv. cabitata) and mustard (B. juncea Coss.) on three AM species (Acaulospora, Entrophospora and Glomus) and to examine effect of root incorporation into soil on root AM infectivity in maize growing in iron toxicity soil. Experiment 1, cabbage and mustard crop reduced spore density of Acaulospora, but there was no effect on spore density of Entrophospora. While, mustard crop had more effect on Glomus spore density than cabbage crop. Experiment 2, AM spore from two conditions; without and with 6 weeks of root residues (cabbage, mustard and maize) incorporation was examined for its infectivity in maize roots. At D21, without root incorporated, the infectivity of Acaulospora, Entrophospora and Glomus were not different. By contrast, cabbage and mustard root incorporation depressed infec-tivity of Acaulospora but, there was no effect on Entrophospora. Whereas, cabbage root incorporation only depressed infectivity of Glomus. However, AM infectivity was recovered at D42. These results suggested that Brassica root incorporated into soil was the actual effect on the viability of AM spore resulting in reduction of AM infectivity at the early stage.
ARTICLE | doi:10.20944/preprints202308.2142.v1
Subject: Medicine And Pharmacology, Endocrinology And Metabolism Keywords: Transferrin; Iron; Adipocyte; Insulin Resistance; Type 2 Diabetes Mellitus
Online: 31 August 2023 (07:14:33 CEST)
Transferrin (TF) is a key iron carrier protein. Studies in human cohorts and in cultured adipocytes suggested that decreased transferrin expression and intracellular iron in adipocytes leads to impaired insulin responsiveness and causes differential expression of genes involved in metabolism, insulin action, and obesity. While suggestive, these studies did not definitively prove in an intact organism that altering TF expression in adipocytes is sufficient to affect glucose homeostasis and insulin resistance. In this study we created a mouse model of decreased transferrin expression only in adipocytes (Trf+/-Cre+/-) to test the hypothesis that iron trafficking in adipose tissue is sufficient to affect insulin sensitivity. Area under the glucose curve (AUCg) after intraperitoneal glucose administration was increased in the Trf+/-Cre+/- mice compared to wild type (WT) mice on a normal chow diet, and the mice were slightly heavier (p=0.02 for both). Homeostasis Model of Insulin Resistance (HOMA-IR) values were also significantly higher in the Trf+/- Cre+/- mice (p<0.05). Thus, supporting our hypothesis, analysis of mice with decreased expression of TF restricted to adipocytes showed that a decrease in adipocyte TF is sufficient to affect insulin resistance, weight, and glucose homeostasis.
ARTICLE | doi:10.20944/preprints202308.0402.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: arsenic; iron oxide NPs; transcriptional factor; gene; SDS-PAGE
Online: 4 August 2023 (11:43:13 CEST)
Arsenic (As) is the most poisonous metalloid with negative effects on the plant and ecosystem. In the current study, observed that iron oxide nanoparticles (NPs) affected the molecular features of rice under arsenic (As) stress. The result showed that 1-D electrophoresis (SDS-PAGE) demonstrated variable expression of protein profiles. The polypeptide pattern was altered in the SDS-PAGE under arsenic stress. The findings also showed that low molecular weight polypeptides (MTs) expression was maximum under arsenic stress, while iron oxide NPs decreased the expression of these polypeptides and reduced the arsenic stress. RT-PCR was used to analyse the expression of the MYB transcriptional factor, WRKY, and OsGF14 genes in the rice plant. The results showed that these genes were up-regulated in response to arsenic stress, iron oxide NPs reduced arsenic stress, and Myeloblastosis (MYB), WRKY, and OsGF14 genes had very low expression levels. Our work showed that iron oxide nanoparticles (NPs) not only reduced the effects of arsenic stress but also decreased the expression of stress-related genes and metallothioneins (MTs).
REVIEW | doi:10.20944/preprints202307.0915.v1
Subject: Chemistry And Materials Science, Materials Science And Technology Keywords: Iron oxides; Synthesis; SPIONs; magnetism; bacterial cellulose; new materials
Online: 13 July 2023 (10:52:50 CEST)
Iron oxide nanoparticles have been investigated due to their suitable characteristics for diverse applications in the fields of biomedicine, electronics, water/wastewater treatment and sensors. Maghemite, magnetite and hematite are the most widely studied iron oxide particles and have ferrimagnetic characteristics. When very small, however, these particles have superparamagnetic properties and are called superparamagnetic iron oxide nanoparticles (SPIONs). Several methods are used for the production of these particles, such as coprecipitation, thermal decomposition and microemulsion. However, the variables of the different types of synthesis must be assessed to achieve greater control over the particles produced. In some studies, it is possible to compare the influence of variations in the factors for production with each of these methods. Thus, researchers use different adaptations of synthesis based on each objective and type of application. With coprecipitation, it is possible to obtain smaller, more uniform particles with adjustments in temperature, pH and the types of reagents used in the process. With thermal decomposition, greater control is needed over time, temperature as well as the proportion of surfactants and organic and aqueous phases in order to produce smaller particles and a narrower size distribution. With the microemulsion process, the control of the confinement of the micelles formed during synthesis through the proportions of surfactant and oil makes the final particles smaller and less dispersed. These nanoparticles can be used as additives for the creation of new materials, such as magnetic bacterial cellulose, which has different innovative applications. Composites that have SPIONs, which are produced with greater rigour with regards to size and distribution, have superparamagnetic properties and can be used in medical applications, whereas materials containing larger particles have ferromagnetic applications. To arrive at a particular particle with specific characteristics, researchers must be attentive to both the mechanism selected and the production variables to ensure greater quality and control of the materials produced.
ARTICLE | doi:10.20944/preprints202306.0502.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: resveratrol; curcumin; halloysite nanotubes; kojic acid; iron chelation, antibacterial.
Online: 7 June 2023 (07:15:16 CEST)
Nowadays, there is evidence that bacteria can contribute to cancer formation and interfere with therapy by mediating its carcinogenesis and related infection. Moreover, it is acknowledged that microbial infections and antibiotic resistance represent severe economic and health risks to society. These facts have led to the developing of several new techniques for impeding crucial biological processes in microbial cells. One of these techniques centers on using metal-chelating agents, which can disrupt the microorganism's vital metal metabolism by obstructing metal uptake and bioavailability for critical reactions. Additionally, nanotechnology has made a wide range of nanomaterials available for possible uses in the antibacterial industry. This complex field is shaped by antimicrobial nanoparticles, also investigated as therapeutic and drug-delivery tools. Halloysite nanotubes (HNTs) are naturally occurring tubular clay nanomaterials consisting of aluminosilicate kaolin sheets rolled up several times. The aluminon and siloxane groups on the surface of HNTs facilitate the formation of hydrogen bonds with biomaterials on their surface. These properties make HNTs crucial in a wide range of applications, such as in environmental sciences, wastewater treatment, dye removal, nanoelectronics and nanocomposite fabrication, catalytic studies, coatings for glass or anti-corrosive coatings, cosmetics, flame retardants, stimulus-response, and in forensic sciences. This work aimed to produce an antibacterial material by combining the properties of halloysite nanotubes with the ability of kojic acid to chelate iron. Starting from kojic acid, a simple nucleophilic substitution involving the hydroxyl groups on the surface of the nanotubes was performed. The obtained material was characterized by IR and SEM, and its ability to chelate iron was evaluated. Finally, the capacity to load drugs such as resveratrol and curcumin was also evaluated by UV analysis. In this way, a new bio-based material that can be used as a drug carrier and antimicrobial was produced.
ARTICLE | doi:10.20944/preprints202306.0371.v1
Subject: Chemistry And Materials Science, Electronic, Optical And Magnetic Materials Keywords: metamaterials; broad-band absorption; iron-cobalt alloy; electromagnetic coupling
Online: 6 June 2023 (03:56:25 CEST)
This study presents a tri-layer broadband metamaterial absorber which operates in the GHz range. The absorber was composed of a polyhedral iron-cobalt alloy/graphite nanosheet material arranged in a flat sheet with two punched-in rings for the top layer, a continuous FR-4 layer at the middle, and a continuous copper layer at the bottom. For the normal incidence of electromagnetic wave, the proposed absorber demonstrated an exceptional broadband absorption in a frequency range of 7.9-14.6 GHz, revealing an absorption exceeding 90%. The absorption magnitude remains to be above 90% in a frequency range of 8-11.1 GHz for transverse-electric-polarized waves at incident angles up to 55°. For both transverse-magnetic- and electric-polarized waves, the absorption exceeds 90% in a frequency range of 9.5-14.6 GHz. The physical mechanism behind the absorption properties is analyzed thoroughly through the electric- and magnetic-field distributions. The obtained results could contribute potentially to the development of microwave applications based on metamaterial absorbers, such as radar-stealth technology, electromagnetic shielding for health safety and reduced electromagnetic interferences for high-performance communications and electronic devices.
ARTICLE | doi:10.20944/preprints202305.0903.v1
Subject: Engineering, Civil Engineering Keywords: sediment model; sulfur and iron cycles; semi-enclosed bay
Online: 12 May 2023 (08:11:39 CEST)
In eutrophic waters, such as Mikawa Bay, Japan, anoxic bottom water develops in summer. This causes sulfide release into seawater by sulfate reduction in the sediment, leading to environmental problems. The addition of iron to sediments is a method used to improve the sediment environment, which was devised from a natural phenomenon. However, this method has not yet been quantitatively evaluated. In this study, we aim to quantitatively evaluate the suppressive effect of iron on sulfide release. First, we develop a sediment model that focuses on S and Fe. We then attempted to reproduce the observations and experiments on sulfide dynamics using the model. Consequently, the proposed model was able to reproduce field sulfur and Fe dynamics in sediments. Additionally, the model described the characteristics of sulfide release considering the effects of additive iron materials. Finally, we conducted predictive calculations and quantitatively evaluated the effects of adding iron materials to the sediments in terms of sulfur and iron cycles.
ARTICLE | doi:10.20944/preprints202305.0614.v1
Subject: Chemistry And Materials Science, Metals, Alloys And Metallurgy Keywords: Spheroidal graphite Cast Iron; Boron; Pearlite; Mechanical properties; Microstructure
Online: 9 May 2023 (08:46:37 CEST)
This study investigated the impact of boron and copper on the microstructure and mechanical properties of Spheroidal graphite Cast Iron (SCI). The addition of boron increased the ferrite content, while copper increased the stability of pearlite. The interaction between boron and copper significantly increased the ferrite content. Differential Scanning Calorimetry (DSC) revealed that boron decreased the enthalpy change of the α + Fe3C -> γ transformation and increased the enthalpy change of the α -> γ transformation. The addition of boron and copper reduced the tensile and yield strength but increased elongation and impact energy. The findings provide valuable insights into the effect of boron and copper on SCI, facilitating the design and development of high-performance SCI materials.
ARTICLE | doi:10.20944/preprints202303.0150.v1
Subject: Medicine And Pharmacology, Pediatrics, Perinatology And Child Health Keywords: support caregivers’ potential; food consumption; iron supplement; anemia prevention
Online: 8 March 2023 (08:41:09 CET)
Children under two years old are at risk for anemia because young children have an increased need for iron for their physical growth and brain development. The purpose of this study was designed to evaluate the effects of a caregiver potential support program on anemia prevention in children six months to two years old attending the subdistrict health-promoting hospital in Thasala District, Nakhon Si Thammarat Province. This study was quasi-experimental. The sample included children aged six months to two years old and their caregivers, who were selected by random sampling and allocated to either the experimental or control group, with 40 pairs per group. The experimental group received a potential support program, while the control group received regular care. Both groups were followed for 12 weeks. The instruments used were the potential caregiver assessment, children’s anemia assessment, and a program to support the potential of primary caregivers. Descriptive statistics, chi-square, and t-tests were used to analyze the data. The results revealed that 11.4% of the children had anemia, and a hematocrit count of less than 33% (range = 30-40, M = 34.89, SD = 1.97). The mean scores of knowledge about anemia and iron supplementation after using the program in the experimental group and control group were significantly different (p < 0.001). The mean scores of knowledge about anemia in the experimental and control group were 15.75, SD = 0.54, and 13.28, SD = 1.43 respectively. The mean scores of knowledge about iron supplementation in the experimental and control group were 10.75, SD = 0.49, and 8.15, SD = 1.54 respectively. It was found that the experimental group had a higher mean score on food care behaviors than the control group for 6-11 months and 1-2 years, with statistical significance. The experimental group also had a higher mean score of care behaviors concerning children’s consumption of medicine than the control group (M = 58.20, SD = 4.05; M = 45.78, SD = 9.66, respectively), (p < 0.001). The mean score of the hematocrit level for the experimental group was found to be higher than the control group after receiving the program (M = 35.80, SD = 1.55; M = 34.83, SD = 2.14, respectively), (p < 0.05). Therefore, healthcare providers should support caregivers' capacity to provide continued care for children to prevent anemia.
ARTICLE | doi:10.20944/preprints202207.0019.v1
Subject: Chemistry And Materials Science, Chemical Engineering Keywords: catalysts; iron oxides; cobalt; oxygen; oxidation; phenol; magnetic composites
Online: 1 July 2022 (16:42:17 CEST)
The development and improvement of methods for the synthesis of environmentally friendly catalysts based on base metals is currently an urgent and promising task of modern catalysis. Catalysts based on nanoscale magnetite and maghemite have fast adsorption-desorption kinetics and high chemical activity. The purpose of this work was to obtain magnetic composites, determine their physicochemical characteristics and verify their activity in the process of liquid-phase oxidation of phenol with oxygen. Magnetic nanocomposites were obtained by chemical co-deposition of salts of ferrous and trivalent iron. The synthesized magnetic composites were studied by X-ray diffractometry, energy dispersive X-ray fluorescence and Mössbauer spectroscopy, IR-Fourier spectroscopy, elemental analysis. To increase the catalytic activity in oxidative processes, the magnetite surfaces were modified using cobalt nitrate salt. Further, CoFe2O4 was stabilized by adding polyethylenimine (PEI) as a surfactant. Preliminary studies of the oxidation of phenol with oxygen, as the most typical environmental pollutant were carried out on the obtained Fe3O4, CuFe2O4, CoFe2O4/PEI catalysts. The spectrum of the reaction product shows the presence of CH in the aromatic ring and double C=C bonds, stretching vibrations of the C=O groups of carbonyl compounds; the band at 3059 cm–1 corresponds to the presence of double C=C bonds, the band at 3424 cm–1 hydroquinone compounds. The band at 1678 cm–1 and the intense band at 1646 cm–1 refer to vibrations of the С=О bonds of the carbonyl group of benzoquinone. Peaks at 1366 cm–1 and 1310 cm–1 can be related to the vibrations of C–H and C–C bonds of the quinone ring. Thus it was demonstrated that produced magnetic composites based on iron oxide are quite effective in the oxidation of phenol with oxygen.
ARTICLE | doi:10.20944/preprints202110.0313.v1
Subject: Chemistry And Materials Science, Applied Chemistry Keywords: membrane transport; Cyanex 923; iron(III); manganese (II); separation.
Online: 21 October 2021 (14:10:48 CEST)
The transport of iron(III) from Fe(III)-Mn(II)-HCl mixed solutions through a flat-sheet supported liquid membrane is investigated, being the carrier phase of Cyanex 923 (commercially available phosphine oxide extractant) dissolved in Solvesso 100 (commercially available diluent), as a function of hydrodynamic conditions, concentration of manganese and HCl in the feed phase, and carrier concentration in the membrane phase. A transport model is derived that describes the transport mechanism, consisting of diffusion through a feed aqueous diffusion layer, a fast interfacial chemical reaction, and diffusion of the Fe(III)-Cyanex 923 complex across the membrane phase. The membrane diffusional resistance (Δm) and feed diffusional resistance (Δf) are calculated from the model, and their values are 145 s/cm and 361 s/cm, respectively. It is apparent that the transport of iron(III) is mainly controlled by diffusion through the aqueous feed boundary layer, being the thickness of this layer calculated as 2.9x10-3 cm. Since Mn(II) is not transported through the membrane phase, the present system allows to the purification of this manganese-bearing solutions.
ARTICLE | doi:10.20944/preprints202103.0161.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: chicken eggs; quail eggs; fatty acids; iron; zinc; cholesterol
Online: 4 March 2021 (14:02:38 CET)
All over the world birds’ eggs are an important and valuable component of the human diet. The study aimed to compare the content of lipid components and their nutritional value as well as iron and zinc levels in chicken and quail eggs commonly available on the market. In egg lipids, unsaturated acids were dominated, especially oleic acid, the content of which was about 40% of total fatty acids (TFA). Linoleic acid was the major polyunsaturated fatty acid. Compared to other products of animal origin, eggs were characterized by favourable values of lipid quality indices, especially index of atherogenicity, thrombogenicity and hypocholesterolemic to hypercholesterolemic ratio. In the present study, no differences in the content of tested nutrients between eggs from different production methods (organic, free-range, barn, cages), as well as inter-breed differences were noticed. Cluster analysis showed that eggs enriched in n3 PUFA (according to producers’ declaration) differ from other groups of chicken eggs. However, only in eggs from one producer, the amount of EPA and DHA exceed 80 mg per 100 g, entitling to use the nutrition claim on the package. Quail eggs differed from chicken eggs in FA profile; they also had much higher iron and cholesterol levels.
COMMUNICATION | doi:10.20944/preprints202012.0365.v1
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: corrosion; amino acids; inhibitors; steel; iron; Monte Carlo simulation
Online: 15 December 2020 (10:09:29 CET)
This research evaluates the inhibitory effect of L-amino acids (AAs) with different side chain lengths on Fe surface implementing Monte Carlo (MC) simulation. A quantitative and qualitative description of the adsorption behavior of AAs on the iron surface has been carried out. Calculations have shown that the absolute values of the adsorption energy of L-amino acids increase with side chain prolongation; they are also determined by the presence of heteroatoms. AAs from nonpolar and basic groups have the best adsorption ability to the iron surface, which indicates their highest inhibitory efficiency according to the results of MC simulation.
REVIEW | doi:10.20944/preprints201907.0277.v1
Subject: Biology And Life Sciences, Animal Science, Veterinary Science And Zoology Keywords: thalassemia; iron overload; chelation therapy; gene therapy; blood transfusion
Online: 25 July 2019 (01:20:41 CEST)
Thalassemia is genetic blood disease cause by absence or decrease of one or more of the globin chain synthesis. Beta thalassemia is characterized by one or more mutations in beta globin gene. Absence or reduced amount the of beta globin chains cause ineffective erythropoiesis which leads to anemia. Beta thalassemia has been further divided into three main forms: Thalassemia minor/silent carrier, major and intermedia. More severe form is thalassemia major in which patients depend upon blood transfusion for survival and high level of iron occur as a consequence of consistent blood transfusion. Over loaded iron invokes the synthesis of reactive oxygen species that are toxic in redundancy and triggering the impairment to vascular, endocrine and hepatic system. Thalassemia can be diagnosed and detected through various laboratory tests such as blood smear, prenatal testing (genetic testing of amniotic fluid), DNA analysis (genetic testing) and complete blood count. Treatment of thalassemia intermedia is symptomatic but it can also be managed by splenectomy and folic supplementation. While thalassemia major can be treated by transplantation of bone marrow, regular transfusion of blood and iron chelation treatment, stimulation of fetal hemoglobin production, hematopoietic stem cell transplantation and gene therapy.
ARTICLE | doi:10.20944/preprints201906.0084.v1
Subject: Engineering, Industrial And Manufacturing Engineering Keywords: manufacturing; energy efficiency; life cycle assessment; aluminium; cast-iron
Online: 11 June 2019 (06:39:26 CEST)
Considering the manufacturing of automotive components, there exists a dilemma around the substitution of traditional Cast Iron (CI) with lighter metals. Nowadays, aluminium alloys, being lighter compared to traditional materials, are considered as a more environmentally friendly solution. However, the energy required for the extraction of the primary materials and manufacturing of components is usually not taken into account in this debate. In this study, an extensive literature review has been performed to estimate the overall energy required for the manufacturing of an engine cylinder block using (a) cast iron and (b) aluminium alloys. Moreover, data from over 100 automotive companies, ranging from mining companies to consultancy firms, have been collected in order to support the soundness of this investigation. The environmental impact of the manufacturing of engine blocks made of these materials is presented with respect to the energy burden; the “cradle-to-grave approach” has been implemented to take into account the energy input of each stage of the component lifecycle starting from the resource extraction and reaching to the end-of-life processing stage. Our results indicate that although aluminium components contribute towards reduced fuel consumption during their use phase, the vehicle distance needed to be covered in order to compensate for the up-front energy consumption related to the primary material production and manufacturing phases is very high. Thus, the substitution of traditional materials with lightweight ones in the automotive industry should be very thoughtfully evaluated.
ARTICLE | doi:10.20944/preprints201905.0305.v1
Subject: Chemistry And Materials Science, Materials Science And Technology Keywords: Gray cast iron, Wear resistance, Intermetallic phase, SEM, Hardness
Online: 27 May 2019 (09:49:38 CEST)
Gray cast iron is one of the most important engineering materials that has many applications in various industries including automotive and machinery manufacturing due to its mechanical properties, wear resistance, machining potentials and low price. In this research effect of adding aluminum and silicon to composition of gray cast iron on microstructure and wear resistance was studied. Moreover, it was investigated the role of formation of Fe-Al-Si intermetallic compound in final properties of the alloy. For studying wear resistance of samples pin-on-disc method was carried out. The results showed that addition of aluminum to gray cast iron causes formation of ferrite matrix, which leads to a decrease in hardness value. Increasing silicon content up to 2 wt. % in cast iron with 4 wt. % aluminum intensifies the formation of ferrite matrix, while further increase to 3 wt. % causes emerging a Fe-Al-Si intermetallic phase. Improvement in hardness value was achieved by increasing silicon content from 3 wt. % to 4 wt. % due to the increased percentage of intermetallic phase. Effect of intermetallic phase on decreasing wear rate was showed by studying microstructure and hardness values, however the lowest wear resistance was observed in aluminum bearing cast iron containing 2 wt. % silicon.
ARTICLE | doi:10.20944/preprints201904.0213.v1
Subject: Engineering, Mechanical Engineering Keywords: gray cast iron; wear resistance; intermetallic phase; SEM; hardness
Online: 19 April 2019 (09:43:07 CEST)
Gray cast iron is one of the most important engineering materials that has many applications in various industries including automotive and machinery manufacturing due to its mechanical properties, wear resistance, machining potentials and low price. In this research effect of adding aluminum and silicon to composition of gray cast iron on microstructure and wear resistance was studied. Moreover, it was investigated the role of formation of Fe-Al-Si intermetallic compound in final properties of the alloy. For studying wear resistance of samples pin-on-disc method was carried out. The results showed that addition of aluminum to gray cast iron causes formation of ferrite matrix, which leads to a decrease in hardness value. Increasing silicon content up to 2 wt. % in cast iron with 4 wt. % aluminum intensifies the formation of ferrite matrix, while further increase to 3 wt. % causes emerging a Fe-Al-Si intermetallic phase. Improvement in hardness value was achieved by increasing silicon content from 3 wt. % to 4 wt. % due to the increased percentage of intermetallic phase. Effect of intermetallic phase on decreasing wear rate was showed by studying microstructure and hardness values, however the lowest wear resistance was observed in aluminum bearing cast iron containing 2 wt. % silicon.
ARTICLE | doi:10.20944/preprints201810.0006.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: iron oxide nanoparticles, shape anisotropy, nanoplates, nanocubes, synthesis mechanisms
Online: 1 October 2018 (11:44:11 CEST)
Iron oxide nanoparticles are widely used as contrast agent for MRI and may be used as therapeutic agent by magnetic hyperthermia if they display a high magnetic anisotropy. Considering the effect of the nanoparticles shape on anisotropy, the reproducible shape control of nanoparticles is currently a challenge of synthesis methods. By investigating reaction parameters which are the iron precursor structure, the water content and the amount of the surfactant, sodium oleate, reported to trigger the cubic shape, iron oxide nanoparticles with different shape and composition were observed to form. In particular, iron oxide nanoplates have been thus synthesized. The effect of the surfactant coming from precursor was taking into account by using in house iron stearates bearing either two or three stearate chains and the negative effect of water on shape was confirmed by considering these precursors after their dehydration. Nanocubes with straight faces and a FeO@Fe3-xO4 composition were obtained only with dehydrated precursors and 50% of sodium oleate in the oleic acid and sodium oleate surfactant mixtures. When iron stearates with three chains led mainly to nanocubes in presence of soduim oleate, Iron stearates with two chains led to the formation of nanoplates with 80% of sodium oleate. The original flat shape of the plates was confirmed with 3D TEM tomography. The investigation of the synthesis mechanisms confirmed the major role of deprotonated carboxylic acid and of the heating rate to drive the cubic shape of nanoparticles and showed that the nanoplate formation would depend mainly on the nucleation step and possibly on the presence of a given ratio of oleic acid and deprotonated carboxylic acid.
ARTICLE | doi:10.20944/preprints201703.0039.v1
Subject: Chemistry And Materials Science, Inorganic And Nuclear Chemistry Keywords: alkanes; amides; hydrogen peroxide; dinuclear complexes; iron complexes; metallasiloxanes
Online: 7 March 2017 (09:23:03 CET)
Two types of heterometallic (Fe(III),Na) silsesquioxanes [Ph5Si5O10]2[Ph10Si10O21]Fe6(O2‒)2Na7(H3O+)(MeOH)2(MeCN)22.214.171.124(MeCN), I, and [Ph5Si5O10]2[Ph4Si4O8]2Fe6Na6(O2‒)3(MeCN)8.5(H2O)8.44, II, were obtained and characterized. X-Ray studies established distinctive structures of both products, with pair of Fe(III)-O-based triangles surrounded by siloxanolate ligands, giving fascinating cage architectures. Complex II proved to be catalytically active in the formation of amides from alcohols and amines, thus becoming a rare example of metallasilsesquioxanes performing homogeneous catalysis. Benzene, cyclohexane and other alkanes, as well as alcohols, can be oxidized in acetonitrile solution to phenol, the corresponding alkyl hydroperoxides and ketones, respectively, by hydrogen peroxide in air in the presence of catalytic amounts of complex II and trifluoroacetic acid. Thus, the cyclohexane oxidation at 20 °C gave oxygenates in very high for alkanes yield (48% based on alkane). The kinetic behaviour of the system indicates that the mechanism includes the formation of hydroxyl radicals generated from hydrogen peroxide in its interaction with diiron species. The latter are formed via monomerization of starting hexairon complex with further dimerization of the monomers.
ARTICLE | doi:10.20944/preprints201810.0137.v1
Subject: Chemistry And Materials Science, Physical Chemistry Keywords: anoxic iron oxidation; abiogenic ferric iron; high-subcritical water; alkaline; ferric oxides; ferric silicates; amorphous silica; origin of life; fluid inclusions; geobiotropy
Online: 8 October 2018 (10:42:53 CEST)
The expression "Follow the water" is used in order to recognize inside the universe, life as it exists on Earth. It is shown here that the expression "Follow the water in its high-subcritical state" can be used in order to recognize the components of life which form prior to the emergence of life. This specific state of water leaves signatures inside the minerals which are produced during high-subcritical water/rock interaction.
ARTICLE | doi:10.20944/preprints202311.0698.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: neuroblastoma; extracellular vesicles; iron oxide nanoparticles; biomimetic models; precision medicine
Online: 10 November 2023 (11:36:59 CET)
Using nanoparticles (NPs) in drug delivery has exhibited promising therapeutic potential 13 in various cancer types. Nevertheless, several challenges must be addressed, including the 14 formation of the protein corona, reduced targeting efficiency and specificity, potential immune 15 responses, and issues related to NP penetration and distribution within 3-dimensional tissues. 16 To tackle these challenges, we have successfully integrated iron oxide nanoparticles into 17 neuroblastoma-derived extracellular vesicles (EVs) using the parental labeling method. We first de- 18 veloped a tissue-engineered (TE) neuroblastoma model, confirming the viability and proliferation 19 of neuroblastoma cells for at least 12 days, supporting its utility for EV isolation. Importantly, EVs 20 from long-term cultures exhibited no differences compared to short-term cultures. Concurrently, 21 we designed Rhodamine (Rh), Polyacrylic acid (PAA)-functionalized magnetite nanoparticles 22 (Fe3O4@PAA-Rh) with high crystallinity, purity, and superparamagnetic properties (average size: 23 9.2 ± 2.5 nm). We then investigated the internalization of Fe3O4@PAA-Rh nanoparticles within 24 neuroblastoma cells within the TE model. Maximum accumulation was observed overnight while 25 ensuring robust cell viability. However, nanoparticle internalization was low. Taking advantage of 26 the enhanced glucose metabolism exhibited by cancer cells, glucose (Glc)-functionalized nanoparti- 27 cles (Fe3O4@PAA-Rh-Glc) were synthesized, showing superior cell uptake within the 3D model 28 without inducing toxicity. These glucose-modified nanoparticles were selected for parental labeling 29 of the TE models, showing effective NPs encapsulation into EVs. 30 Our research introduces innovative approaches to advance NPs delivery. By partially addressing 31 the challenges associated with 3D systems, optimizing internalization, and enhancing NPs stability 32 and specificity through EV-based carriers. Also, our findings hold the promise of more precise and 33 effective cancer therapies while minimizing potential side effects.
ARTICLE | doi:10.20944/preprints202209.0345.v1
Subject: Biology And Life Sciences, Ecology, Evolution, Behavior And Systematics Keywords: Abiotic Stress; Amazon; Canga; Iron mining; Mineland Rehabilitation; Proteomics; Symbiosis
Online: 22 September 2022 (13:34:43 CEST)
Mimosa acutistipula is endemic to Brazil and grows in ferruginous outcrops (canga) in Serra dos Carajás, eastern Amazon, where one of the largest iron ore deposits in the world is located. Plants that develop in these ecosystems are subject to severe environmental conditions and must have adaptive mechanisms to grow and thrive in cangas. Mimosa acutistipula is a native species used to restore biodiversity in post-mining areas in canga. Understanding the molecular mechanisms involved in the adaptation of M. acutistipula in canga is essential to deduce the ability of native species to adapt to possible stressors in rehabilitating minelands over time. In this study, the root proteomic profiles of M. acutistipula grown in a native canga ecosystem and rehabilitating minelands were compared to identify essential proteins involved in the adaptation of this species in its native environment and that should enable its establishment in rehabilitating minelands. The results showed differentially abundant proteins, where 436 proteins with significant values (p < 0.05) and fold change ≥ 2 were more abundant in canga and 145 in roots from the rehabilitating minelands. Among them, a representative amount and diversity of proteins were related to responses to water deficit, heat, and responses to metal ions. Other identified proteins are involved in biocontrol activity against phytopathogens and symbiosis. This research provides insights into proteins involved in M. acutistipula responses to environmental stimuli, suggesting critical mechanisms to support the establishment of native canga plants in rehabilitating minelands over time.
ARTICLE | doi:10.20944/preprints202104.0467.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: Tripodal Ligands; pseudohalide coligands; Iron Complex; Spin crossover; Magnetic properties
Online: 19 April 2021 (12:03:37 CEST)
Reactions of Fe(II) with the tris-(pyridin-2-yl)ethoxymethane (py3C-OEt) tripodal ligand in presence of the pseudohalide ancillary NCE- (E = S, Se, BH3) ligands led to a series of three mononuclear complexes formulated as [Fe(py3C-OEt)2][Fe(py3C-OEt)(NCE)3]2·2CH3CN, with E = S (1), BH3 (2) and Se (3). Single crystal characterizations (complexes 1-2) and X-ray powder diffraction (complexes 1-3) reveal monomeric isomorph structures formed by the spin crossover (SCO) anionic [Fe(py3C-OEt)(NCE)3] complex, associated with the low spin (LS) cationic [Fe(py3C-OEt)2]2+ complex and two solvent acetonitrile molecules. In the [Fe(py3C-OEt)2]2+ cation, the Fe(II) is coordinated by two py3C-OEt tridentate ligands, while the [Fe(py3C-OEt)(NCE)3] anion displays a hexacoordinated environment involving three N-donor atoms of one py3C-OEt ligand and three nitrogen atoms arising from of the three (NCE) coligands. The magnetic studies show the presence of gradual SCO behavior for the three complexes: a one-step transition around 205 K for 1 and two step-transitions for compounds 2 and 3, centred at 245 K and 380 K for 2, and at 170 K and 298 K for 3. The magnetic behaviors of complexes 1 and 2 remain unchanged when heating up to 500 K, while complex 3 shows significant changes which are caused by the crystallisation solvent loss above room temperature.
ARTICLE | doi:10.20944/preprints202103.0552.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Huma Serum Albumin; Acinetobacter baumannii; quorum sensing; iron; human fluids.
Online: 22 March 2021 (15:49:16 CET)
Acinetobacter baumannii is a nosocomial pathogen capable of causing serious infections associated with high rates of morbidity and mortality. Due to its antimicrobial drug resistance profile, A. baumannii is categorized as an urgent priority pathogen by the Centers for Disease Control and Prevention in the United States and priority group 1 critical microorganism by the World Health Organization. Understanding how A. baumannii adapts to different host environments may provide critical insights into strategically targeting this pathogen with novel antimicrobial and biological therapeutics. Exposure to human fluids was previously shown to alter the gene expression profile of a highly drug susceptible A. baumannii strain A118 leading to persistence and survival of this pathogen. Herein, we explore the impact of human pleural fluid (HPF) and human serum albumin (HSA) on the gene expression profile of a highly multi-drug resistant strain of A. baumannii AB5075. Differential expression was observed for ~30 genes, whose products are involved in quorum sensing, quorum quenching, iron acquisition, fatty acid metabolism, biofilm formation, secretion systems and type IV pilus formation. Phenotypic and further transcriptomic analysis using quantitative RT-PCR confirmed RNA-seq data and pointed out a distinctive role of HSA as the molecule involved in A. baumannii response.
ARTICLE | doi:10.20944/preprints202102.0200.v1
Subject: Environmental And Earth Sciences, Atmospheric Science And Meteorology Keywords: Iron ore; Maghemite; Nonstoichiometric magnetite; X-Ray diffraction; Ore characterization
Online: 8 February 2021 (12:13:32 CET)
Maghemite (γ-Fe2O3) is a mineral formed from magnetite oxidation at low temperatures, an intermediate metastable term of the magnetite to hematite oxidation and could be mixed with both. It has magnetic susceptibility similar to magnetite, crystal structure close to magnetite with which it forms a solid solution, while compositionally it equals hematite. Maghemite is thus easily misidentified as magnetite by X-ray diffraction and/or as hematite by spot chemical analysis in iron ore characterization routines. Nonstoichiometric magnetite could be quantified in samples of Brazilian soils and iron ores by the Rietveld method using a constrained refinement of the X-ray patterns. The results were confirmed by reflected light microscopy and Raman spectroscopy, thus qualitatively validating the method. X-ray diffraction with the refinement of the isomorphic substitution of Fe2+ by Fe3+ along the magnetite-maghemite solid solution could help to suitably characterize maghemite in iron ores, allowing for the evaluation of its ultimate influence on mineral processing, by affecting its surface and breakage properties.
ARTICLE | doi:10.20944/preprints202011.0146.v4
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Ferric Uptake Regulation; Fur, Iron(II), Molecular dynamics; DNA; protein
Online: 10 November 2020 (12:23:58 CET)
Ferric uptake regulation protein is a repressor protein which binds an AT rich region of DNA (the iron box). Fur binds as a dimer in a helix turn helix mode and it is activated by iron(II) and other divalent transition metal ions at elevated concentrations in a process to regulate the ion uptake. Each transition metal ion induces certain conformational changes to aid the Fur binding, both the N-terminal and C-terminal domains take part in binding to DNA in addition to His 88 and His 86 residues. The process is discussed in view of experimental reports. Fe(II), Mn(II) and Co(II) activate Fur to bind DNA experimentally but Zinc plays a structural role and does not activate Fur to bind DNA.
ARTICLE | doi:10.20944/preprints202007.0223.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: Iron oxides; nanoparticles; organic dye degradation; photocatalytic effect; antibacterial behavior
Online: 11 July 2020 (03:38:48 CEST)
Currently, the use of sustainable chemistry as an ecological alternative for the generation of products or processes, free of polluting substance has assumed a preponderant role. The aim of this work is propose a bioinspired, facile, at low cost, non-toxic and environmentally friendly alternative to obtaining magnetic nanoparticles whit a majority phase of magnetite (Fe3O4). Is important to empathize that the synthesis was based on the chemical reduction through the Cnicus Benedictus extract, whose use as reducing agent has not been reported in the synthesis of iron oxides nanoparticles. In addition, the Cnicus Benedictus is abundant endemic plant in Mexico, with several medicinal properties and a large number of natural antioxidants. The obtained nanoparticles exhibited significant magnetic and antibacterial properties and an enhanced photocatalytic activity. The crystallite size of the Fe3O4 nanoparticles (Fe3O4 NP’s) was calculated by Williamson-Hall method. The photocatalytic properties of the Fe3O4 NP´s were studied by kinetics absorptions models in the Congo red (CR) degradation. Finally the antibacterial effect of the Fe3O4 NP´s were evaluated mediated the Kirby-Bauer method against E. coli and S. aureus bacteria. This route offers a green alternative to obtain Fe3O4 NP´s with remarkable magnetic, photocatalytic and antibacterial properties.
ARTICLE | doi:10.20944/preprints201704.0003.v1
Subject: Chemistry And Materials Science, Metals, Alloys And Metallurgy Keywords: Iron Aluminum Alloys; Cold/ Hot PM; Compressibility Factor; Wear Resistance.
Online: 3 April 2017 (16:23:00 CEST)
Iron powders having average particle sizes of ~40µm are mechanically mixed thoroughly with aluminum powders ranging from 1 to 10 in wt.% with an average particle size of ~10µm. Two different powder metallurgical techniques cold and hot pressing are used to study the effect of the additive element powder on the mechanical properties, wear properties and the microstructure of the iron based alloys. The hot pressing technique was performed at a temperature up to 500°C at 445.6 MPa. The cold pressing technique was performed at 909 MPa in room temperature. By increasing the Al content to 10 wt. % in the base Fe-based matrix, the hardness was decreased from 780 to 690 MPa and the radial strength was decreased from 380 to 202 MPa with reductions of 11.5% and 40%, respectively. Improvement of the wear resistance with the increase addition of the Al powder to the Fe matrix up to 5 times was achieved compared to the alloy without Al addition for different wear parameters namely; wear time and sliding speed.
ARTICLE | doi:10.20944/preprints201609.0112.v1
Subject: Chemistry And Materials Science, Surfaces, Coatings And Films Keywords: carbonyl iron; composites film; external magnetic field; microwave absorption properties
Online: 28 September 2016 (10:32:52 CEST)
The carbonyl iron particles were dispersed in a polychloroprene rubber (CR) matrix under an external magnetic field for practical application as microwave absorption composites film. The film prepared under external magnetic field with a thickness of only 0.54 mm showed least reflection loss of -15.98 dB and the reflection loss value less than -10.0 dB over the frequency range of 11.4~14.8 GHz. In comparison with the microwave absorption properties of calculation by transmission line theory based on the tested relative complex permittivity and permeability and film prepared by general route without external magnetic field, the film made with external magnetic field exhibited more excellent microwave absorption properties, strongly depending on the increment of anisotropy and rearrangement of magnetic particles. The results indicated the composite film made under external magnetic field have excellent microwave absorption properties, which suggest that the composites thin film could be used as a thinner and lighter microwave absorber.
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: Second-Order Derivative (SOD) method; Graphic method; Potential Energy Scan (PES); Charge-Transfer complex; Iron(III) bromide; Iron(V) complex; Transition metal-halogen tandem catalysis
Online: 21 June 2021 (14:08:50 CEST)
To date, theoretical analyses have provided several useful methods/algorithms for studying transition states and non-covalent interactions. Potential Energy Scan (PES) is one such method that has found wide application in the physicochemical community. Analyzing the PES profiles of the catalytic system of FeBr3 in Electrophilic Aromatic Substitution (EAS) with molecular halogens, one can notice an obvious difference from the modern textbook mechanisms proposed in this area of study. Moreover, the newly presented Graphic Methodology (GM) allows a simple and reliable transition state determination even for very weakly bound charge transfer complexes using second-order derivatives as an efficient tool in the graphical analysis. Relative errors that can be reduced to a few parts per thousand in transition state estimation make this method a potentially very useful tool in further graphical studies of non-covalent interactions. Studies performed using high-precision semiempirical methods suggest that the process of halonium ion quenching proceeds along a completely different pathway, suggesting a possible novel transition metal-nonmetal catalytic system involved in the EAS electrophilic quenching step. The results presented here strongly suggest a future GM application that is widely used and the introduction of pseudo and pre-transition states as new terms in the description of non-covalent interactions.
ARTICLE | doi:10.20944/preprints202308.1849.v1
Subject: Medicine And Pharmacology, Pediatrics, Perinatology And Child Health Keywords: restless sleep disorder; periodic leg movements during sleep; prematurity; iron deficiency
Online: 28 August 2023 (10:29:19 CEST)
Children with history of prematurity are at higher risk of complications, comorbidities and iron deficiency. In this study we assess the prevalence of restless sleep disorder, as well as that of periodic leg movements during sleep (PLMS) in these children. Retrospective chart review of sleep studies in children aged 1-18 years, with history of prematurity. Only diagnostic studies in children without diagnosis of a genetic syndrome or airway surgery or tracheostomy were included. Three groups were compared, children with PLMS index>5, children with restless sleep disorder (RSD), and children with neither elevated PLMS index nor RSD. During the study, 2,577 sleep studies were conducted. Ninety-two studies fit our criteria and were included in analysis. Median birth age was 31 weeks, interquartile range (IQR) 27-34 weeks. Thirty-two (34.8%) children were referred for restless sleep and 55 (59.8%) for snoring; after polysomnography 18% were found to have PLMS index >5/hour, 14% fit the criteria for RSD. There were no statistically significant differences in polysomnographic parameters between the children with RSD, PLMS and the remaining group, except for lower obstructive apnea/hypopnea index (Kruskal-Wallis ANOVA 8.621, p=0.0135) in the RSD group (median 0.7, IQR 0.3-0.9) than in the PLMS (median 1.7, IQR 0.7-3.5), or than in the nonRSD/nonPLMS group (median 2.0, IQR 0.8-4.5). There was elevated frequency of RSD and elevated PLMS in children with history of prematurity that might be linked to the increased risk of iron deficiency in premature infants. These new results add new knowledge on the prevalence of RSD in these children.
ARTICLE | doi:10.20944/preprints202306.1525.v1
Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: cefiderocol; A. baumannii; disk diffusion; broth microdilution; E-test; iron-depletion
Online: 21 June 2023 (10:20:03 CEST)
The reference method for cefiderocol antimicrobial susceptibility testing is broth microdilution (BMD) with iron-depleted-Mueller-Hinton (ID-MH) medium, whereas breakpoints recommended for disk diffusion (DD) are based on MH-agar plates. We aimed to compare the performance of the commercial BMD tests ComASP (Liofilchem) and UMIC (Bruker), DD and E-test using MH- and ID-MH-agar plates with the reference BMD method using 100 carbapenem-resistant-A. baumannii isolates. Standard BMD was performed according to the EUCAST guidelines, DD and E-test were carried out using two commercial MH-agar plates (bioMérieux and Liofilchem) and an in-house ID-MH-agar plate, while ComASP and UMIC were performed according to the manufacturer’s guidelines. DD performed with the ID-MH-agar plates led to a higher categorical agreement (CA, 95.1%) with standard BMD and fewer categorization errors compared to the commercial MH-agar plates (CA bioMérieux 91.1%, Liofilchem 89.2%). E-test on ID-MH-agar plates exhibited a significantly higher essential agreement (EA, 75%) with standard BMD compared to the two MH-agar plates (EA bioMérieux 57%, Liofilchem 44%), and showed a higher performance in detecting high-level resistance than ComASP and UMIC (mean log2 difference with standard BMD for resistant isolates of 0.5, 2.83 and 2.08, respectively). In conclusion, DD and E-test on ID-MH-agar plates exhibit a higher diagnostic performance than on MH-agar plates and the commercial BMD methods. Therefore, we recommend using ID-MH-agar plates for cefiderocol susceptibility testing of A. baumannii.
ARTICLE | doi:10.20944/preprints202304.0991.v1
Subject: Chemistry And Materials Science, Materials Science And Technology Keywords: CO2 hydrogenation; CO2 utilization; light hydrocarbons; manganese-iron catalysts, olefin compounds
Online: 26 April 2023 (12:56:05 CEST)
Mn-promoted bulk iron catalysts with high specific surface area (82-211 m2.g-1) were synthesized by coprecipitation followed by drying under supercritical conditions. The catalysts were tested in the CO2 hydrogenation reaction. The Mn-promoted iron catalysts showed better textural properties than the bare Fe2O3 catalyst, allowing better dispersion of the active phase, easier reduction of iron oxide, better carburization of iron oxides and higher catalytic activity than the bare Fe2O3 catalyst. The best activity results were obtained by catalyst promotion with a very low amount of Mn (Mn/Fe ratio of 0.05). Upon steady-state conditions (T=340 ºC, total pressure of 20 bar and H2/CO2=3), this catalyst showed high CO2 conversion (44.2%) and selectivity to C2-C4 hydrocarbons (68%, olefin to paraffin ratio of 0.54), while the selectivity to C5+ hydrocarbons, CH4 and CO was about 3.2, 38.5 and 5%, respectively. A close correlation was found between catalyst textural properties and CO2 conversion. The most active MnFe-0.05 catalyst shows high stability during 72 h of reaction related to low amount of soft coke formation and catalyst activation through the formation of χ-Fe5C2 phase during the on-stream reaction.
REVIEW | doi:10.20944/preprints202206.0253.v1
Subject: Biology And Life Sciences, Biophysics Keywords: Bioinorganic chemistry; metal-binding; structural biology; zinc; iron; copper; transition metals
Online: 17 June 2022 (09:30:07 CEST)
All living organisms require some metal ions for their energy production as well as metabolic and biosynthetic processes. Within cells, metal ions are involved in the formation of adducts interact with metabolites and macromolecules (proteins and nucleic acids). The proteins that require binding to one or more metal ions to be able to carry out their physiological function are called metalloproteins. About one third of all protein structures in the Protein Data Bank involve metalloproteins. Over the past few years there has been a tremendous progress in the number of computational tools and techniques making use of 3D structural information to support the investigation of metalloproteins. This trend has been boosted also by the successful applications of neural networks and deep learning approaches in molecular and structural biology at large. In this review, we discuss recent advances in the development and availability of resources dealing with metalloproteins from a structure-based perspective. We start by addressing tools for the prediction of metal-binding sites (MBSs) using structural information on apo-proteins. Then, we provide an overview of methods for and lessons learned from the structural comparison of MBSs in a fold-independent manner. We then move to describing databases of metalloprotein/MBS structures. Finally, we summarize recent DL applications enhancing the functional interpretation of metalloprotein structures.
ARTICLE | doi:10.20944/preprints202203.0321.v1
Subject: Engineering, Electrical And Electronic Engineering Keywords: electric vehicle; electromagnetic model; optimization; silicon-iron; thermal model; Vanadium Cobalt
Online: 24 March 2022 (02:59:21 CET)
The use of cobalt-iron (VaCoFe) core is investigated as an alternative to silicon-iron (FeSi) on the design of interior permanent magnet synchronous motors (IPMSM). A spoke-type IPMSM geometry is optimized considering FeSi and VaCoFe cores for a torque range up to 40 N.m, providing a general comparative analysis between materials, considering the application of a 4-motor competition vehicle’s powertrain. A genetic optimization algorithm is applied over a hybrid analytical/finite-element model of the motor to provide sufficiently accurate electromagnetic and thermal results within a feasible time. VaCoFe can result in an estimated increase of up to 5 % in efficiency for the same torque, or up to 64 % torque increase for the same efficiency level. After optimization, and using a detailed time-dependent model, a potential 3.2 % increase in efficiency, a core weight reduction of 4.1 %, and a decrease of 9.6 % in the motor’s core volume was found for the VaCoFe at 20 Nm. In addition, for the same motor volume, the VaCoFe allows an increase of 51.9 % of torque with an increase of 1.1 % of efficiency, when compared with FeSi.
ARTICLE | doi:10.20944/preprints202111.0470.v1
Subject: Chemistry And Materials Science, Inorganic And Nuclear Chemistry Keywords: ionic liquids; liquid-liquid extraction; iron extraction; 8-hydroxyquinoline; acetylacetone; thenoyltrifluoroacetone
Online: 25 November 2021 (11:58:50 CET)
(200 words) Imidazolium ionic liquids containing acetylacetone, thenoyltrifluoroacetone, or 8-hydroxyquinoline, respectively, were used as the extracting agents for the separation of traces of iron (III) from its aqueous solutions with or without citric and oxalic acids. The results show that 8-hydroxyquinoline in imidazolium ionic liquids extract iron quantitatively from all the tested solutions including complexing ones, regardless indications of unexpected iron behavior/speciation.
ARTICLE | doi:10.20944/preprints202110.0221.v1
Subject: Environmental And Earth Sciences, Environmental Science Keywords: river; forest; bog; permafrost; carbon; major ions; iron; colloids; trace element
Online: 15 October 2021 (08:59:43 CEST)
Assuming that climate warming in the WSL will lead to a northward shift of the forest and permafrost boundaries, a “substituting space for time” approach predicts an increase in concentration of DIC and labile major and trace elements and a decrease of the transport of DOC and low soluble trace metals in the form of colloids in the main stem of the Ob River. However, an unknown factor is the change in hydrochemistry of the largest southern tributary, the Irtysh River, which is impacted by permafrost-free steppe and forest-steppe zone. Overall, seasonally-resolved transect studies of large riverine systems of western Siberia are needed to assess the hydrochemical response of this environmentally-important territory to on-going climate change.
ARTICLE | doi:10.20944/preprints202010.0589.v1
Subject: Environmental And Earth Sciences, Atmospheric Science And Meteorology Keywords: Natural Hydrogen System; circular depressions; Archean iron-rich Craton; Western Australia
Online: 28 October 2020 (11:57:31 CET)
There is a marked momentum towards the use of clean hydrogen energy as an alternative for fossil fuels. Renewable energies such as solar and wind are being used to generate hydrogen from the water hydrolysis process. Indeed, this approach stores renewable energies in the form of combustible hydrogen for other energy uses. The other alternative that could be economically more cost-effective at the current technology stage is to explore the natural “Hydrogen System” where the natural hydrogen is generated and accumulated within the earth system, the same that stands for a “Petroleum System”. The Discovery of a large accumulation of relatively pure natural hydrogen (H2) in Mali has triggered the opportunity of searching for natural hydrogen accumulations in other countries. The generation of hydrogen from a circular depression in Mali and some other countries is linked to the presence of geologically very old iron-rich basement rocks. Solid-liquid redox reactions between iron-rich minerals and groundwater that split water are a possible source of H2 in deep basement rocks. It is believed that the hydrogen degassing may be detected by surface topographic circular to sub-circular shallow depressions. Chemical processes such as dissolution by hydrogen are considered to play the main role in the formation of the circular depressions through preferential vertical hydrogen migration channel. Archean iron-rich Yilgarn Craton that covers a vast area of Western Australia (WA) contains abundant iron-rich mafic-ultramafic rocks. The craton reveals many surficial circular depressions visible through satellite images. The area has abundant fault systems and is blanketed with Eocene sedimentary rocks containing high-quality reservoir rocks. All these characteristics seem to provide most of the required elements, such as hydrogen source, migration pathway, and reservoir rock for a “Hydrogen System” in this area.
ARTICLE | doi:10.20944/preprints202003.0462.v1
Subject: Medicine And Pharmacology, Dietetics And Nutrition Keywords: iron; blood donation; restless legs syndrome; quality of life; sleep; fatigue
Online: 31 March 2020 (22:32:59 CEST)
Background: Besides anemia, iron deficiency may cause more subtle symptoms including those of the restless legs syndrome (RLS), the chronic fatigue syndrome (CFS) or sleeping disorders. Objective: The aim of this pre-planned secondary analysis was to compare the frequency and severity of symptoms associated with iron deficiency before and after (intravenous or oral) iron supplementation in iron deficient blood donors. Methods/Design: Prospective, randomized, controlled, single centre trial. (ClinicalTrials.gov: NCT01787526). Setting: Tertiary care center in Graz, Austria Participants: 138 female and 38 male whole blood and platelet apheresis donors aged ≥18 and ≤65 years with iron deficiency (ferritin ≤30ng/ml at the time of blood donation). Interventions: Intravenous iron (1 g ferric carboxymaltose, n=86) or oral iron supplementation (10 g iron fumarate, 100 capsules, n=90). Measurements: Clinical symptoms were evaluated by a survey before iron therapy (visit 0, V0) and after 8-12 weeks (visit 1, V1) including questions about symptoms of RLS, CFS, sleeping disorders, quality of life and symptoms like headaches, dyspnoea, dizziness, palpitations, pica and trophic changes of fingernails or hair. Results: We found a significant improvement in the severity of symptoms for RLS, fatigue and sleep quality (p<0.001). Furthermore, a significant decrease of headaches, dyspnoea, dizziness and palpitations was reported (p<0.05). There was no difference between the type of iron supplementation (intravenous versus oral) and clinical outcome data. Conclusion: Iron supplementation in iron deficient blood donors may be an effective strategy to improve symptoms related to iron deficiency and the wellbeing of blood donors.
ARTICLE | doi:10.20944/preprints201912.0036.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: iron oxide nanoparticles; hydrothermal synthesis; high pressure; magnetic properties; thermal stability
Online: 4 December 2019 (04:10:31 CET)
Magnetic iron oxide particles are used for in vitro diagnostics for nearly 40 years. Due to their unique physical, chemical, thermal and mechanical properties, as well as biocompatibility and low toxicity in the human body, iron oxide nanoparticles have been used in many biomedical applications, such as contrast agents for magnetic resonance imaging, carriers for controlled drug delivery and immunoassays, but also in magnetic hyperthermia. Our aim is to investigate the effect of pressure and temperature on the structural, thermal and magnetic properties of iron oxide nanomaterials prepared by hydrothermal synthesis. Iron oxide nanoparticles were synthesized at temperatures of 100-200°C and pressures of 20-1000 bar. It has been found that pressure influences the type of iron oxide crystalline phase. Thus, for lower pressure values (< 100 bar), iron oxide is predominantly formed as hematite, while at pressures > 100 bar, the major crystalline phase is goethite. The complex thermal analysis revealed the polymorphic changes of iron oxides at different temperatures. The existence of specific magnetite and hematite phases in all thermally treated samples are evidenced through the specific Verwey and Morin transitions highlighted by ZFC-FC (Zero Field Cooled-Field Cooled) measurements, whereas their relative content is precisely provided by Mössbauer spectroscopy.
ARTICLE | doi:10.20944/preprints201910.0134.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: stingless bees; honey; pollen; Serra dos Carajás; Amazônia; Melipona; Iron mining
Online: 11 October 2019 (11:49:06 CEST)
The pollen content of honey samples collected in the years 2017 and 2019 from experimental apiaries of Melipona seminigra pernigra Moure & Kerr 1950 installed in campo rupestre on canga (CRC) vegetation of the Serra dos Carajás, southeastern Amazonia, was analyzed to understand the local variability of floral resources occurring on natural and disturbed areas. Around one hundred pollen types were identified mainly belonging to Fabaceae, Myrtaceae and Euphorbiaceae (31, 6 and 5 types, respectively). The N5 mine presented the highest pollen richness with 95 pollen types identified, almost twice of those identified in the other areas, including the better preserved ones. Eighty percent of the pollen types are rare with concentrations ≤ 2,000 pollen grains/10 g; the remaining types are the most abundant and frequent, and are considered the primary bee sources (PBS). PBS correspond mostly to native plants such as Tapirira guianensis Aubl., Protium spp., Aparisthmium cordatum (A.Juss.) Baill., Mimosa acutistipula var. ferrea Barneby, Periandra mediterrânea (Vell.) Taub., Miconia spp., Pleroma carajasense K.Rocha, Myrcia splendens (Sw.) DC., Serjania spp. and Solanum crinitum Lam. All pollen types were identified during both seasons, but higher pollen concentration are related to the dry period (June-September). The statistical analysis indicated that there was no significant difference in honey pollen data between the natural and disturbed areas since the plant species considered as PBS in this work are intensively used in revegetation of degraded area (RDA) processes by mining activities.