ARTICLE | doi:10.20944/preprints202111.0277.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: Multi-material additive manufacturing; Functionally graded materials; Conventional Manufacturing; Interface Issues
Online: 16 November 2021 (08:50:21 CET)
Additive manufacturing has already been established as a highly versatile manufacturing technique with demonstrated potential to completely transform conventional manufacturing in the future. The objective of this paper is to review the latest progress and challenges associated with the fabrication of multi-material parts using additive manufacturing technologies. Various manufacturing processes and materials used to produce functional components were investigated and summarized. The latest applications of multi-material additive manufacturing (MMAM) in automotive, aerospace, biomedical and dentistry field were demonstrated. Investigation on the current challenges were also carried out to predict the future direction of MMAM processes. It is concluded that the further research and development needed in the design of multi-material interfaces, manufacturing processes and material compatibility of MMAM parts are necessary.
REVIEW | doi:10.20944/preprints202105.0326.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: organic; conventional; potato; quality; disease
Online: 14 May 2021 (11:44:40 CEST)
Interest in organic foods is increasing at a moment when humanity is facing a range of health challenges including the concern that some conventionally produced foods may pose possible adverse effects on human and livestock health. With the increasing human population, intensive production is increasingly trending towards high-input systems that aim to close yield gaps, increase crop yields, and develop new crop varieties with higher yield potential and tolerance to biotic and abiotic stresses, all within the context of incorporating specific traits to satisfy consumer demand. Potato (Solanum tuberosum L.) is one of the most consumed foods under different cultural diets, however its production faces some challenges related to soilborne diseases, marketable yield and quality, sugars and dry matter content of the produced tubers, tuber content in terms of nitrate, minerals, vitamins, bioactive compounds and antioxidants, and consumer appreciation regarding the sensory characteristics of tubers and processed products. Different studies have been investigating some of these challenges, with sometimes straightforward and sometimes connflicting results. This variability in research results indicates the general non-transferability of the results from one location to another under the same management practices in addition to differences in plant material. This review compares some characteristics of raw or boiled potato and processed products from potato tubers grown organically and conventionally. Ideally, such information may be of benefit in decision making by consumers in their dietary choices, by potato growers in their selection of crop management practices, and by scientists looking at potential areas for future research on potatoes.
CASE REPORT | doi:10.20944/preprints202101.0400.v1
Subject: Medicine & Pharmacology, Dentistry Keywords: ameloblastoma; conventional; segmental resection; titanium plate
Online: 20 January 2021 (13:32:46 CET)
Ameloblastoma is an aggressive slow growing benign epithelial odontogenic tumor usually associated with an unerupted third molar. In this report, we present the case of a 71-year-old male with a large swelling on the left mandibular region causing a remarkable facial asymmetry. After clinical, radiological, and histopathological examinations the diagnosis of conventional ameloblastoma was made. To avoid probable recurrence our treatment choice was a segmental mandibular resection with the placement of a reconstructive titanium plate to maintain the space for subsequent bone graft.
ARTICLE | doi:10.20944/preprints202104.0664.v1
Subject: Engineering, Electrical & Electronic Engineering Keywords: deep learning; feedback control; conventional controller; neural network; backpropagation.
Online: 26 April 2021 (12:16:18 CEST)
Training data for a deep learning (DL) neural network (NN) controller are obtained from the input and output signals of a conventional digital controller that is designed to provide the suitable control signal to a speciﬁed plant within a feedback digital control system. It is found that if the DL controller is suﬃciently deep (four hidden layers), it can outperform the conventional controller in terms of settling time of the system output transient response to a unit-step reference signal. That is, the DL controller introduces a damping eﬀect. Moreover, it does not need to be retrained to operate with a reference signal of diﬀerent magnitude, or under system parameter change. Such properties make the DL control more attractive for applications that may undergo parameter variation, like sensor networks.
CONCEPT PAPER | doi:10.20944/preprints202007.0390.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Farmer’s right; food sovereignty; seed production system; conventional breeding
Online: 17 July 2020 (15:22:09 CEST)
Farmer’s right and their sovereignty is an important issue related with intellectual property rights and agrobiodiversity management. To boost farmer’s right, a conceptual hypothesis is proposed where they choose either a new high yielding variety or the existing one and apply conventional breeding approaches to select the seed for next years in their own fields. Although farmers produce seeds traditionally from several years, they have not been guided with scientific discipline to produce sufficient amount of quality seeds. This new concept suggests trained farmers can use breeding approaches to produce quality seed for their own use.
Subject: Biology, Anatomy & Morphology Keywords: Cannabis sativa; Germplasm preservation; Droplet vitrification; Conventional vitrification; Tissue culture
Online: 19 July 2021 (18:13:48 CEST)
Cannabis has developed into a multi-billion dollar industry that relies on clonal propagation of elite genetics with desirable agronomic and chemical phenotypes. While the goal of clonal propagation is to produce genetically uniform plants, somatic mutations can accumulate during growth and compromise long-term genetic fidelity. Cryopreservation is a process in which tissues are stored at cryogenic temperatures, halting cell division and metabolic processes to facilitate high fidelity germplasm preservation. In this study, a series of experiments were conducted to optimize various stages of cryopreservation and develop a protocol for long-term germplasm storage of Cannabis sativa. The resulting protocol uses a standard vitrification procedure to cryopreserve nodal explants from in vitro shoots as follows: Nodes were cultured for 17 hours in a pre-culture solution (PCS), followed by a 20 minute treatment in a loading solution (LS), and a 60 minute incubation in plant vitrification solution 2 (PVS2). The nodes were then flash frozen in liquid nitrogen, re-warmed in an unloading solution at 40°C, and cultured on basal MS culture medium in the dark for 5 days followed by transfer to standard culture conditions. This protocol was tested across 13 genotypes to assess the genotypic variability. The protocol was successful across all 13 genotypes, but significant variation was observed in tissue survival (43.3-80%) and regrowth of shoots (26.7-66.7%). Plants grown from cryopreserved samples were morphologically and chemically similar to control plants for most major traits, but some differences were observed in the minor cannabinoid and terpene profiles. While further improvements are likely possible, this study provides a functional cryopreservation system that works across multiple commercial genotypes for long-term germplasm preservation.
ARTICLE | doi:10.20944/preprints202107.0423.v1
Subject: Life Sciences, Biochemistry Keywords: non-conventional yeasts; Saccharomyces; fermentation; beer; dry-hopping; brewing potential
Online: 19 July 2021 (16:08:39 CEST)
Consumer demands for new sensory experiences have driven the research of unconventional yeasts in beer. While much research exists on the use of various common Saccharomyces cerevisiae strains as well as non-Saccharomyces yeasts, there exists a gap in knowledge regarding other non-cerevisiae Saccharomyces species in the fermentation of beer, outside that of S. pastorianus. Here, five distinct species of Saccharomyces from the UC Davis Phaff Yeast Culture Collection, as well as one interspecies hybrid from Fermentis, were chosen to ferment 40 L pilot scale beers. S. kudriavzevii, S. mikatae, S. paradoxus, S. bayanus, and S. uvarum yeasts were fermented in duplicate, with one fermenter in each pair receiving 10 g/L dry-hop during fermentation. Analytical measurements were made each day of fermentation and compared to controls of SafAle US-05 and SafLager W 34/70 for commercial brewing parameters of interest. Finished beers were also analyzed for aroma, taste, and mouthfeel to determine the flavor of each yeast as it pertains to brewing potential. All beers exhibited spicy characteristics, likely from the presence of phenols; dry-hopping increased fruit notes while also increasing perceived bitterness and astringency. All of the species in this study displayed great brewing potential, and might be an ideal addition to beer depending on a brewery’s desire to experiment with flavor and willingness to bring a new yeast into their production environment
ARTICLE | doi:10.20944/preprints202106.0052.v1
Subject: Life Sciences, Biochemistry Keywords: antibiotics; conventional; microbiology; microfluidics; microscopy; mycobacterium smegmatis; population; single cell
Online: 2 June 2021 (08:32:03 CEST)
To reveal rare phenotypes in bacterial populations conventional microbiology tools should be advanced to generate rapid, quantitative, accurate and high-throughput data. The main drawbacks of widely used traditional methods for antibiotic studies include low sampling rate and averaging data for population measurements. To overcome these limitations microfluidic-microscopy systems have great promise to produce quantitative single-cell data with high sampling rates. Using Mycobacterium smegmatis cells we applied both conventional assays and a microfluidic-microscopy method to reveal antibiotic-tolerance mechanisms of wild type and the msm2570::Tnmutant cells. Our results revealed that the enhanced antibiotic tolerance mechanism of the msm2570::Tn mutant was due to the low number of lysed cells during the antibiotic exposure compared with wild-type cells. This is the first study that characterized the antibiotic-tolerance phenotype of the msm2570::Tn mutant that has a transposon insertion in the msm2570 gene encoding a putative xanthine/uracil permease, which enrolls in uptake of nitrogen compound during nitrogen limitation. The experimental results indicate that the msm2570::Tn mutant can be further interrogated to reveal antibiotic killing mechanisms, in particularly, antibiotics those targets cell wall integrity.
ARTICLE | doi:10.20944/preprints202003.0146.v1
Subject: Social Sciences, Other Keywords: conventional agriculture; land degradation; small-holders; multinomial logistic regression; Nepal
Online: 9 March 2020 (01:24:35 CET)
Land degradation is a critical issue globally putting our future generations at risk. The decrease in farm productivity over the years is evidence of land degradation severity in Nepal. Among the many strategies in place, agroforestry, which is an integrated tree-based farming, is widely recommended to address this productivity issue. This paper thoroughly examines what influences the choice of agroforestry adoption by farmers and what discourages the adoption. For this, a total of 288 households were surveyed using a structured questionnaire. Two agroforestry practices were compared with conventional agriculture with the help of the Multinomial Logistic Regression (MNL) model. The likelihood of adoption was found to be influenced by gender; the male-headed households were more likely to adopt the tree-based farming practice. Having a source of off-farm income was positively associated with the adoption decision of farmers. Area of farmland was found being the major constraint to agroforestry adoption for smallholder farmers. Some other variables that affected positively included livestock herd size, provision of extension service, home-to- forest distance, farmers’ group membership and awareness of farmers about environmental benefits of agroforestry. Irrigation was another adoption constraint that the study area farmers were faced with. The households with means of transport and with larger family (household) size were found to be reluctant towards agroforestry adoption. A collective farming practice could be a strategy to engage the smallholder farmers in agroforestry.
ARTICLE | doi:10.20944/preprints201910.0063.v1
Subject: Biology, Plant Sciences Keywords: lilium sp.; in vitro protocol; conventional pathway; bulb production; timeline
Online: 7 October 2019 (11:16:43 CEST)
Lily–belong to the genus Lilium is one of the top cut flowers worldwide. Production and propagation of bulblets in vitro is an important approach for high-volume production, but not proved satisfactory. Hence, the aim of this study was to describe and compare the performances of morphological characteristics of the lily bulb in vivo produced by in vitro and conventional culture method and compare the production timelines in vitro vs conventional culture method. In results, it seems clear that in vitro re-culture of lily bulblet was able to be sustained and maintained its growth and so, ontogenic development after their performance in soil. Our results demonstrate that in the conventional pathway, the course of bulblet growth to bulb and ontogenic development took 3–4 growing seasons to reach the adult flowering phase. On the other hand, along with the re-culture in vitro, the course of bulb growth and ontogenic development took 1–2 growing seasons to reach the adult flowering phase because of the increasing initial bulb size and advancement of ontogenic development. Other than bulblet production through bulb scale explant, this study represents the first report on the method of in vitro bulb production of lily through re-culture by in vitro pathway with a comparison of the timelines and ontogenic development obtained from in vitro versus conventional pathway.
ARTICLE | doi:10.20944/preprints201909.0054.v1
Subject: Engineering, Other Keywords: Shanghai; water quality; eutrophication; conventional water treatment; secondary water pollution
Online: 5 September 2019 (07:47:59 CEST)
Shanghai is experiencing water supply problems caused by heavy pollution of its raw water supply, deficiencies in its treatment processes and water quality deteoriation in the distribution system. However, little attention has been paid these problems of water quality in raw water, water treatment and household drinking water. Based on water quality data we show that the raw water sources of the Huangpu River and the Changjiang (Yangtze River) estuary are polluted by microbes (TBC), eutrophication (TP, TN and NH3-N), heavy metals (Fe, Mn and Hg) and organic contamination (chemical oxygen demand [COD], detergent and volatile phenols [VP]). The average concentrations of these contaminants in the Huangpu River are almost double that of the Changjiang estuary forcing a rapid shift to the Changjiang estuary for raw water. In spite of filtering and treatment, TN, NH3-N, Fe, COD and chlorine maxima of the treated water and drinking water still exceed the Chinese National Standard (GB5749). We determine that the relevant threats from water source to household water in Shanghai are: 1) eutrophication arising from highly concentrated TN, TP, COD and algal density in the raw water; 2) increasing salinity in the river estuary, especially at the Qingcaosha Reservoir (currently the major freshwater source for Shanghai); 3) more than 50% of organic constituents and by-products remain in treated water; 4) bacteria and turbidity increase in the course of water delivery to users. The analysis presents an holistic assessment of the water quality threats to metropolitan Shanghai in relation to the city’s rapid development.
HYPOTHESIS | doi:10.20944/preprints201702.0018.v1
Subject: Arts & Humanities, Other Keywords: mastery learning strategy; learning retention; achievement; physical geography; conventional method
Online: 5 February 2017 (10:01:59 CET)
The need to alleviate the difficulties of abstraction and improve students’ achievement in Physical Geography informed this research. This study investigated the Effects of Mastery Learning Strategy and Learning Retention on Senior Secondary School Students’ Achievement in Physical Geography. The study adopted the quasi experimental non-equivalent pre-test, post-test control group design. The Multi-stage sampling technique at four levels was used to select four co-educational secondary schools in Ganye Educational Zone in Nigeria. The sample for the study was 218 Senior Secondary School two (SS II) students offering Geography from four intact classes in the four selected secondary schools. The instrument used for data collection was “Physical Geography Achievement and Retention Test” (PGART). The reliability of the instrument was established using Kendall tau b statistic. This gave a reliability index of 0.74. Data collected were analyzed using Mann-Whitney U and t-Test. The results showed that Mastery Learning Strategy has the potentials to improve students’ learning outcomes, retention and achievement in all spheres of cognitive domain in Physical Geography better than the Conventional Method. Hence the need to incorporate this teaching strategy during instruction so that learners would be guided to learn meaningfully and be assisted to retain content learnt in Geography.
REVIEW | doi:10.20944/preprints202206.0415.v1
Subject: Chemistry, Organic Chemistry Keywords: 3,4-DHPo; 1,4-DHPs; multicomponent reaction; non-conventional synthesis; synthetic precursors
Online: 30 June 2022 (06:11:45 CEST)
3,4-Dihydro-2(1H)-pyridones (3,4-DHPo) and their derivatives are privileged structures present in natural products, which has been increased its relevance due to its biological activity in front of a broad range of targets, but especially for its importance as synthetic precursors of a variety of compounds with marked biological activity. Taking into account the large number of contributions published over the years regarding this kind of heterocycle, here we presented a current view of 3,4-dihydro-2(1H)-pyridones (3,4-DHPo), which include general aspects such as those related to nomenclature, synthesis, and biological activity; but also highlighting the importance of DHPo as building blocks of other relevance structures.
ARTICLE | doi:10.20944/preprints202204.0069.v2
Subject: Medicine & Pharmacology, Gastroenterology Keywords: hepatocellular carcinoma; conventional transarterial chemoembolization; emulsion; lipiodol; glass membrane emulsification device
Online: 6 June 2022 (05:53:21 CEST)
Background: Transarterial chemoembolization (TACE) is the standard treatment for BCLC-B hepatocellular carcinoma (HCC). A novel glass membrane emulsification device (GMD) produces a high percentage of water/oil emulsions with homogeneous and stable droplets. There are few reports on the efficacy of GMD-conventional-TACE (GMD-c-TACE)；therefore, we aimed to evaluate the effectiveness of GMD-c-TACE. Methods: Seventy-one patients with HCC with tumor diameter <5 cm who underwent c-TACE with and without GMD were included in this study to investigate local recurrence and hepatic functional reserve. Results: The local recurrence rates of TACE without GMD were 3.0% at 6 months, 16.7% at 12 months, and 35.0% at 18 months, around where it plateaued. Hence, the local recurrence rates in the GMD-c-TACE group were 7.7% at 14 months and 23.1% at 20 months, respectively. Thus, GMD-c-TACE had a significantly lower local recurrence. Multivariate analysis showed that GMD-c-TACE could suppress local recurrence and maintain hepatic reserve. Conclusions: GMD-c-TACE allows dense lipiodol accumulation in the tumor and attainment of good local control. Additionally, the inhibition of the release of anticancer drugs may maintain hepatic reserve. GMD-c-TACE is useful in preventing local recurrence and is expected to become the standard treatment form of c-TACE in the future.
ARTICLE | doi:10.20944/preprints202205.0410.v1
Subject: Social Sciences, Other Keywords: mugwort; perennial cropping; conventional rotations; sustainable agri-culture; soil microbial community
Online: 31 May 2022 (05:20:06 CEST)
Perennial cropping play vital roles in regulating soil carbon sequestration and thus mitigating climate change. However, how perennial cropping affects soil microbial community remains elusive. Using a field investigation, this study was conducted to examine the effects of mugwort cropping along a chronosequence (that is, wheat-maize rotation, 3-year, 6-year, and 20-year mugwort cropping) on soil microbial community in temperate regions of Northern China. The results showed that the highest total, actinomycetes, and fungi PLFAs were found in the 3-year mugwort cropping soils. All PLFAs of microbial groups were lowest in the 20-year mugwort cropping soils. All of the three cropping years of mugwort increased network complexity of soil microbial community. Changes in total nitrogen and phosphorus content as well as the ratio of ammonium nitrogen to nitrate nitrogen could be primarily explain the variations in soil microbial community along the mugwort cropping chronosequence. Our observations highlight the contrasting impacts of soil microbial community to short-term and long-term mugwort cropping compared to conventional rotations and would have critical implications for sustainable agricultural management under perennial cropping in temperate regions.
ARTICLE | doi:10.20944/preprints201810.0544.v1
Subject: Life Sciences, Other Keywords: Acrylamide, Free Asparagine, Cropping Systems, Organic, Conventional, Agriculture, Cereals, Species, Cultivars
Online: 23 October 2018 (16:19:26 CEST)
As bakery products contribute considerably to the daily intake of the carcinogen acting substance acrylamide (AA), the aim of this study was to evaluate the impact of the cropping system (conventional vs. organic farming) on AA precursor levels of free asparagine (Asn) across different cultivars of the cereal species, namely winter wheat (Triticum aestivum), winter spelt (Triticum aestivum ssp. spelta) and winter rye (Secale cereale) with simultaneous consideration of gained grain yields and flour qualities. For this purpose, orthogonal field trials were established at two sites in Southwest Germany over two growing seasons (2006-2007 and 2007-2008). The results indicated a significant impact of the cropping system on free Asn contents. Across all species, free Asn contents in the flour were 26 % lower under organic compared to conventional farming. The impact of the cropping system on individual cultivars was obvious with a maximum reduction in free Asn contents of 50 % (e.g. for cultivars Ludwig, Privileg, Capo) if organically produced. For spelt, a significant impact of the cropping system was only found in 2008 with a reduction in free Asn of up to 25 % if organically produced. Across both cropping systems, cultivar Franckenkorn reached the lowest levels of free Asn. For rye, a significant impact of the cropping system was observed only in 2007 with 33 % higher Asn amounts in the conventional cropping system. Independent of the cropping system, rye reached the highest levels of free Asn followed by wheat and spelt. Across both cropping systems, species and cultivars, the amount of free Asn correlated with the AA content in heated flour with R2=0.63***. Furthermore, the results indicated that lower AA contents in bakery products can be achieved by proper selection of species (e.g. 66 % lower if rye is replaced by wheat) and cultivars. With an appropriate choice of the cultivar, a reduction of up to 65 % was possible within wheat, along with a reduction of 44 % within spelt and 12.5 % within rye. In summary, the results indicated that organically produced wheat especially offers the opportunity to significantly lower the AA potential of bread and bread rolls by the choice of raw materials low in free Asn.
ARTICLE | doi:10.20944/preprints202112.0386.v1
Subject: Engineering, Civil Engineering Keywords: energy efficiency; natural building; conventional building; TRNSYS software; temperature; humidity; energy consumption
Online: 23 December 2021 (11:48:08 CET)
The construction field uses up over one-third of the global energy consumption and contribute to 40% of CO2 emissions according to the International Energy Agency (IEA) and the 2020 annual reporter of United Nation, Goal 11 (Make cities inclusive, safe, resilient and sustainable) which discusses sustainable, safe and efficient buildings. Therefore, Morocco has a commitment to this program by publishing the law 47-09 of energy efficiency. This work aims to study the energy efficiency of two types of building, a conventional and a natural building. Conventional building is constructed using concrete, while the natural one uses sand clay and straws. As for the technique of making the natural building, it perpetually follows the same approach accustomed in rural zones of Atlas Mountains in Morocco. In this research we also simulate, temperature and humidity variation inside these buildings using TRNSYS software. Sketch Up software was employed to design these houses. The weather database is used for a typical meteorological year (TMY). In the case of natural building, many building configurations were simulated: roof insulation, floor insulation, different types of glazing and sun protection. What's more, the thermal comfort is revealed to be more conspicuous in the case of natural building.
REVIEW | doi:10.20944/preprints202009.0552.v1
Subject: Biology, Entomology Keywords: Malaria; Amazon; Brazil; Anopheles darlingi; Plasmodium; Control; Challenges; Strategies; Conventional; Novel; Vector; Mosquito
Online: 23 September 2020 (15:26:43 CEST)
In Brazil, malaria transmission is mostly confined to the Amazon, where substantial progress has been achieved towards disease control in the past decade. Vector control has been historically considered a fundamental part of the main malaria control programs implemented in Brazil. However, the conventional vector-control tools have been insufficient to eliminate local vector populations due to the complexity of the Amazonian rainforest environment and ecological features of malaria vector species in the Amazon, especially Anopheles darlingi. Malaria elimination in Brazil and worldwide eradication will require a combination of conventional and new approaches that takes into account the regional specificities of vector populations and malaria transmission dynamics. Here we present an overview on both conventional and novel promising vector-focused tools to curb malaria transmission in the Brazilian Amazon. If well designed and employed, these new vector-based approaches may improve the implementation of malaria-control programs, particularly in remote or difficult-to-access areas and in regions where existing interventions have been unable to eliminate disease transmission. However, much effort still has to be put on research expanding the knowledge of neotropical malaria vectors to set the steppingstones for the development of such innovative tools.
REVIEW | doi:10.20944/preprints202003.0351.v1
Subject: Life Sciences, Biotechnology Keywords: Conventional method; Clustered Regularly Interspaced Short Palindromic Sequence; Genome editing; RNA Interference; TALEN
Online: 23 March 2020 (10:23:45 CET)
Conventional plant breeding has contributed enormously towards feeding the world and has played crucial roles in the development of modern society. The conventional method creates variation by transferring genes between or within the species. In general, these methods are more expensive and takes more time, to overcome these limitations, new technology is required. Genome editing is a powerful tool for biotechnology applications, with the capacity to alter the function of any gene. With the availability of gene information for the majority of the traits, genome editing emerged as a potential to create a new variation with the introduction of any transgene. The important genome editing tools used nowadays are ZFNs, TALEN, Pentatricopeptide repeats protein, adenine base editor, RNA interference, and CRISPR/Cas9. These tools have opened a new era for crop improvement. Due to the complex genetic architecture of most traits, it is challenging to edit genes controlling them. To overcome these challenges, genome editing provides a broader perspective. Among the above-mentioned tools, CRISPR/Cas9 is the most powerful tool for gene editing. These technologies are being used to create abiotic and biotic resistance crop varieties.
ARTICLE | doi:10.20944/preprints202210.0421.v1
Subject: Medicine & Pharmacology, Pathology & Pathobiology Keywords: Postoperative atrial fibrillation; cardiac surgery; conventional extracorporeal circulation; circulating ferritin levels; POAF onset biomarker
Online: 27 October 2022 (05:53:09 CEST)
Background: Postoperative atrial fibrillation (POAF) is the most common arrhythmia after cardiac surgery in conventional extracorporeal circulation (CECC), with an incidence of 15-50%. The POAF pathophysiology is not known, and no blood biomarkers exist. However, an association between increased ferritin levels and increased AF risk, has been demonstrated. Based on such evidence, here, we evaluated the effectiveness of ferritin and other haemato-chemical parameters as a POAF onset biomarker in subjected to cardiac surgery. Materials and Methods: We enrolled 90 patients (mean age= 66.9±2.8 years; 40 men and 20 females) with diverse heart pathologies and subjected to cardiothoracic surgery. Their blood samples were collected and used to determine haemato-chemical parameters. The tree test approach was used to detect the best data-driven ferritin cuff-off value (=141 ng/ml) to predict POAF risk. Results: The data obtained demonstrated significant higher concentrations, absolute values, and percentages, of ferritin, RDW, PLTs, in POAF patients. However, the ferritin resulted to be the independent factor associated with the onset POAF risk. Thus, we detected the ferritin cut-off value, which, when ≥ 141 ng/ml identifies the subjects at the highest POAF risk. Conclusions: Ferritin values≥ 141 ng/ml might be used as predictive POAF biomarker.
ARTICLE | doi:10.20944/preprints202107.0003.v1
Subject: Biology, Anatomy & Morphology Keywords: Conventional agriculture; sustainable agriculture; compost tea; bacteria; biodiversity; Illumina MiSeq sequencing; plant growth; soybean
Online: 1 July 2021 (07:59:55 CEST)
Soil bacteria drive key ecosystem functions, including nutrient mobilization, soil aggregation and crop bioprotection against pathogens. Bacterial diversity is thus considered a key component of soil health. Conventional agriculture reduces bacterial diversity in many ways. Compost tea has been suggested as a bioinoculant that may restore bacterial community diversity and promote crop performance under conventional agriculture. Here, we conducted a field experiment to test this hypothesis in a soybean-maize rotation. Compost tea application had no influence on bacterial diversity or community structure. Plant growth and yield were also unresponsive to compost tea application. Combined, our results suggest that our compost tea bacteria did not thrive in the soil, and that the positive impacts of compost tea applications reported elsewhere may be caused by different microbial groups (e.g., fungi, protists, nematodes) or by abiotic effects on soil (e.g., contribution of nutrients and dissolved organic matter). Further investigations are needed to elucidate the mechanisms through which compost tea influences crop performance.
ARTICLE | doi:10.20944/preprints202212.0082.v1
Subject: Mathematics & Computer Science, Computational Mathematics Keywords: K-means clustering algorithm; Elbow method; Silhouette technique; Kneedle Algorithm; Image Segmentation; Conventional Neural Network.
Online: 6 December 2022 (01:30:03 CET)
The agricultural sector in Palestine has a significant role in its economy. However, the production of this sector is affected by different kinds of plant diseases, specifically leaf diseases. Automatic agricultural leaf disease detection is essential for the early diagnosis and controls the overall health of fields. Image segmentation techniques, clustering, and deep learning are often used to detect diseased leaves. This study proposes a novel hybrid approach based on image classification. The hybrid approach combines the k-means clustering algorithm with Convolutional Neural Network (CNN), where k-means is used to detect the leaf’s infected area, then CNN is used for specifying the disease. We used the PlantVillage dataset for experimental verification as it contains several crops with different kinds of challenging diseases. We also examined the selection of optimal k-value using the Silhouette coefficient, Elbow method, and Kneedle Algorithm. The Silhouette technique was analyzed using three distance metrics; Euclidean, Manhattan, and Cosine. Its scores for the three-distance metrics were low, near-zero, and failed to produce the optimum k value. Besides, the Elbow method was complicated to use in image segmentation in terms of executing and visualizing the k value in its graph plot. Based on verification results, the Kneedle Algorithm produced better results in the consistency of choosing the optimal k value and showed superiority over other approaches. Therefore, the processed images were segmented with the k-means clustering algorithm with a Kneedle algorithm-based k value. Finally, a Convolutional Neural Network (CNN) is trained to classify the type of disease based on analyzing and testing leaf images. The hybrid model achieved high accuracy of 93.79% in disease identification, confirming the proposed model’s robustness.
ARTICLE | doi:10.20944/preprints201906.0222.v1
Subject: Social Sciences, Geography Keywords: water consumption; water metabolism; tourism destination; resilience; non-conventional water resources; sustainable tourism; overtourism; shortage; Spain
Online: 22 June 2019 (11:52:42 CEST)
Tourism, and particularly residential tourism, has led to a change in the urban and demographic model of towns along the European Mediterranean coastline. Water as a limited and limiting resource for the growth of tourism is a popular topic in the scientific literature. However, the incorporation of non-conventional resources (desalination) has meant, in theory, that this limitation has been overcome. The aims of this paper are: a) to identify the different tourism models implanted in this territory and describe them from the point of view of their consumption of water in the demand cycle from 2002 to 2017; b) analyse the hydrosocial cycle, highlighting the measures aimed at satisfying water demand; and c) identify the limitations associated with these hydrosocial systems. To this end, different types of information will be processed, and various complex indicators produced. The results show the importance that demand management and the use of desalinated water in increasing the resilience of this territory to aridity. However, this has generated other problems associated with a tsunami of construction and the continuity of a non-sustainable territorial model.
REVIEW | doi:10.20944/preprints201804.0260.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: conventional heart anatomy; helical ventricular myocardial band; mitral valve opening; isovolumic relaxation time; RV function; diastolic dysfunction
Online: 20 April 2018 (08:10:46 CEST)
Cardiac dynamics are traditionally linked to a left ventricle, right ventricle and septum morphology, a topography that differs from the heart’s 5-century-old anatomic description of containing a helix and circumferential wrap architectural configuration. Torrent Guasp’s helical ventricular myocardial band (HVMB) defines this anatomy and its structure, explains why the heart’s 6 dynamic actions of narrowing, shortening, lengthening, widening, twisting and uncoiling happen. This database raises questions about deductions behind “accepted cardiac mechanics”, and its functional aspects will challenge and overturn them. These suppositions include the LV, RV, and septum description, timing of mitral valve opening, isovolumic relaxation period, reasons for torsion/twisting, untwisting, reasons for longitudinal and circumferential strain, echocardiographic sub segmentation, resynchronization, RV function dynamics, and diastolic dysfunction’s cause and unrecognized septum impairment. Torrent Guasp’s revolutionary contributions may alter future understanding of the diagnosis and treatment of cardiac disease.
REVIEW | doi:10.20944/preprints202106.0163.v1
Subject: Biology, Other Keywords: white biotechnology; metabolic engineering; non-conventional yeast; oleaginous yeast; cell factory; heterologous expression; biodiversity; Yarrowia lipolytica; Yarrowia clade; GMO
Online: 7 June 2021 (10:50:26 CEST)
Among non-conventional yeasts of industrial interest, the dimorphic oleaginous yeast Yarrowia lipolytica appears as one of the most attractive for a large range of white biotechnology applications, from heterologous proteins secretion to cell factories process development. The past, present and potential applications of wild type, traditionally improved or genetically modified Yarrowia lipolytica strains will be resumed, together with the wide array of molecular tools now available to genetically engineer and metabolically remodel this yeast. The present review will also provide a detailed description of Yarrowia lipolytica strains and highlight the natural biodiversity of this yeast, a subject little touched upon in most previous reviews. This work intends to fill this gap by retracing the genealogy of the main Yarrowia lipolytica strains of industrial interest, by illustrating the search for new genetic backgrounds and by providing data about the main publicly available strains in yeast collections worldwide. At last, it will focus on exemplifying how advances in engineering tools can leverage a better biotechnological exploitation of the natural biodiversity of Yarrowia lipolytica and of other yeasts from the Yarrowia clade.
REVIEW | doi:10.20944/preprints201911.0265.v1
Subject: Life Sciences, Microbiology Keywords: craft brewing; saccharomyces cerevisiae; saccharomyces eubayanus; hybrids; 4-vinyl guaiacol; non-conventional yeasts; evolutionary engineering; artisanal fermented food; natural biodiversity
Online: 24 November 2019 (04:35:23 CET)
Beer is a fermented beverage with a history as old as human civilization and its productive process has been spread all around the world becoming unique in every country and iconic of entire populations. Ales and lagers are by far the most common beers; however, the combination of raw materials, manufacture techniques and aroma profiles are almost infinite, so it is not surprising to notice that there is a large amount of different beer styles, each of them with unique characteristics. Nowadays, diversification is becoming increasingly important in the brewing market and the brewers are continuously interested in improving and extending the already wide range of products, especially in craft brewery. One of the major components that can have a deep impact on the final product is yeast, since it is able to convert carbohydrates in wort, especially maltose and maltotriose, into ethanol, carbon dioxide and other minor aroma-active compounds. Saccharomyces cerevisiae (top‐fermenting yeasts used to produce ales) and Saccharomyces pastorianus (cryotolerant bottom‐fermenting hybrids between S. cerevisiae and Saccharomyces eubayanus responsible for the fermentation of lagers) are most used in breweries. However, an increasing number of different yeast starter cultures are commercially available, to improve the production efficiency also at relative low temperatures and to obtain desirable and diversified aroma profiles avoiding undesired compounds. Four main genetic engineering-free trends are becoming popular in craft brewing yeast development: 1) the research for novel reservoirs as source of new performant S. cerevisiae yeasts; 2) the creation of synthetic hybrids between S. cerevisiae and Saccharomyces non-cerevisiae in order to mimic lager yeasts by expanding their genetic background; 3) the exploitation of evolutionary engineering approaches; 4) the usage of non-Saccharomyces yeasts either in co-coculture or in sequential fermentation with S. cerevisiae. In the present work we summarized pro and contra of these approaches and provided an overview on the most recent advances on how brewing yeast genome evolved and domestication took place. Finally, we delineated how the correlations maps between genotypes and relevant brewing phenotypes can assist and further improve the search for novel craft beer starter yeasts.
ARTICLE | doi:10.20944/preprints202110.0399.v1
Subject: Engineering, Energy & Fuel Technology Keywords: Renewable energy; Life cycle analysis; Wind energy; Life cycle assessment; Wind turbine; Carbon footprint; Water consumption; Greenhouse gases; non-conventional renewable sources; Carbon and water footprints.
Online: 27 October 2021 (11:00:58 CEST)
Wind technology is considered to be among the most promising types of renewable energy sources, and due to high oil prices and growing concerns about climate change and energy security, it has been the subject of extensive considerations in recent years, including questions related to the relative sustainability of electricity production when the manufacturing, assembly, transportation and dismantling processes of these facilities are taken into account. The present article evaluates the environmental impacts, carbon emissions and water consumption, derived from the production of electric energy of the Villonaco wind farm, located in Loja-Ecuador, during its entire life cycle, using the Life Cycle Analysis method. Finally, it is concluded that wind energy has greater environmental advantages, since it has lower values of carbon and water footprints than other energy sources. Additionally, with the techniques Cumulative Energy Demand and Energy Return on Investment, sustainability in the production of electricity from wind power in Ecuador is demonstrated; and, that due to issues of vulnerability to climate change, the diversification of its energy mix is essential considering the inclusion of non-conventional renewable sources such as solar or wind, this being the only way to reduce both the carbon footprint and the water supply power.