ARTICLE | doi:10.20944/preprints201810.0266.v1
Subject: Chemistry, Organic Chemistry Keywords: cyclic nucleotide monophosphate; bio-reversible protection; acyloxybenzyl phosphate ester
Online: 12 October 2018 (11:32:45 CEST)
Adenine nucleotide (AN) 2nd messengers such as 3’,5’-cyclic adenosine monophosphate (cAMP) are central elements of intracellular signaling, but many details of underlying processes remain still elusive. Like all nucleotides, cyclic nucleotide monophosphates (cNMPs) are net-negatively charged at physiologic pH which limits their applicability in cell-based settings. Thus, many cellular assays rely on sophisticated techniques like microinjection or electroporation. This setup is not feasible for medium- to high-throughput formats, and the mechanic stress that cells are exposed to raises the probability of interfering artefacts or false-positives. Here, we present a short and flexible chemical route yielding membrane-permeable, bio-reversibly masked cNMPs for which we employed the octanoyloxybenzyl (OB) group. We further show hydrolysis studies on chemical stability and enzymatic activation, and present results of real-time assays, where we used cAMP and Ca2+ live cell imaging to demonstrate high permeability and prompt intracellular conversion of some selected masked cNMPs. Consequently, our novel OB-masked cNMPs constitute valuable precursor-tools for non-invasive studies on intracellular signaling.
ARTICLE | doi:10.20944/preprints201804.0132.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: bio-phosphate; ABC Animal-Bone-Char; 3R pyrolysis; phosphorus recovery; animal by-products; apatite
Online: 10 April 2018 (16:28:11 CEST)
Disrupted nutrient recycling is a significant problem for Europe, while phosphorus and nitrogen are wasted instead of being used for plant nutrition. Mineral phosphate is critical raw material, which contains environmentally hazardous elements such as cadmium and uranium. Therefore, phosphorus recovery from agricultural by-product streams is critically important key priority. Phosphorus recovery from food grade animal bone by-products have been applied researched since 2002 with objective driven evolution progress towards specialized pyrolysis processing technology and animal bone char product (ABC) developments in economical industrial scale. Different animal bone by-products tested under different conditions at 400 kg/h throughput capacity in the continuously operated 3R zero emission autothermal carbonization system. The different material core treatment temperatures (between >300°C and <850°C) were combined with different residence times under industrial productive processing conditions. It has been industrial demonstrated that material core treatment temperature <850°C with 20 minutes residence time is necessary to achieve high quality ABC with useful agronomic value. The output ABC product having concentrated >30% phosphorus pentoxide (P2O5) and specific quality innovative fertilizer for agronomical efficient organic and low input farming applications as functional organic fertilizer, soil improver, growing medium and/or fertilizing product blend with high mineral phosphate fertiliser replacement value.
ARTICLE | doi:10.20944/preprints202107.0007.v1
Subject: Materials Science, Biomaterials Keywords: calcium phosphate; monocalcium phosphate; tricalcium phosphate; calcium carbonate; seashell; bivalve shells
Online: 1 July 2021 (10:48:06 CEST)
The search for sustainable resources remains a subject of global interest and the conversion of the abundantly available bivalve shell wastes to advanced materials is an intriguing method. By grinding, each shell of bivalves (cockle, mussel, and oyster) was transformed to the same crystal type of calcite phase of CaCO3, revealed by FTIR and XRD results. Each individual shell powder was reacted with H3PO4 and H2O to prepare Ca(H2PO4)2•H2O giving an anorthic crystal structure. The mixture of each shell powder and its produced Ca(H2PO4)2•H2O was heated at 900 °C for 3 h, giving rhombohedral crystal -Ca3(PO4)2 powder. FTIR and XRD results of the CaCO3, Ca(H2PO4)2•H2O, and Ca3(PO4)2 prepared from each shell powder are quite similar showing no impurities. Thermal behaviors of CaCO3 and Ca(H2PO4)2•H2O produced from each shell are slightly different. Particle sizes and morphologies of all products are significantly different, affected by the kind of shells used. Overall, the bivalve shell wastes were successfully converted to CaCO3, Ca(H2PO4)2•H2O, and Ca3(PO4)2 by a simple, rapid, environmentally benign, and cost-effective approach, which can be a huge potential in many industries providing both economic and ecological benefits according to the Bio-Circular-Green Economy (BCG) model.
ARTICLE | doi:10.20944/preprints202012.0353.v1
Subject: Materials Science, Biomaterials Keywords: Estonian phosphorite; beneficiation; reverse flotation; phosphate concentrates; phosphate recovery
Online: 14 December 2020 (15:56:13 CET)
Phosphorus is essential and non-substitutable chemical element required for the cellular processes of all living organisms. The main source of phosphorus in the biosphere is phosphate rock. With more than 700 Mt P2O5, Estonia holds the largest sedimentary phosphate rock deposits in European Union. Estonian phosphate rock is principally sandstone that holds abundant remains of phosphatic brachiopod shells and compared to other sedimentary rocks, is particularly outstanding by its remarkably low content of hazardous heavy metals such as Cd and saturated by valuable elements present in the rock such as rear earth elements (REEs).
HYPOTHESIS | doi:10.20944/preprints202007.0610.v1
Subject: Chemistry, Organic Chemistry Keywords: symmetry breaking; dihydroxyacetone phosphate; sn-glycerol-1-phosphate dehydrogenase; sn-glycerol-3-phosphate dehydrogenase; membrane evolution
Online: 25 July 2020 (15:35:55 CEST)
Either stereo reactants or stereo catalysis from achiral or chiral molecules are prerequisite to obtain pure enantiomeric lipid derivatives. We reviewed a few plausible organic syntheses of phospholipids under prebiotic conditions with a special attention to the starting materials as pro-chiral dihydroxyacetone and dihydroxyacetone phosphate (DHAP), which are the key molecules to break symmetry in phospholipids. The advantages of homochiral membranes compared to those of heterochiral membranes were analysed in term of specific recognition, optimal functions of enzymes, membrane fluidity and topological packing. All biological membranes contain enantiomeric lipids in modern bacteria, eukarya and archaea. The contemporary archaea, comprising of methanogens, halobacteria and thermoacidophiles are living under extreme conditions reminiscent of primitive environment and may indicate the origin of one ancient evolution path of lipid biosynthesis. The analysis of lipid metabolism reveals that all modern cells including archaea synthetize enantiomeric lipid precursors from prochiral DHAP. sn-glycerol-1-phosphate dehydrogenase (G1PDH), usually found in archaea, catalyses the formation of sn-glycerol-1-phosphate (G1P), while sn-glycerol-3-phosphate dehydrogenase (G3PDH) catalyses the formation of sn-glycerol-3-phosphate (G3P) in bacteria and eukarya. The selective enzymatic activity seems to be the main strategy that evolution retained to obtain enantiomeric pure lipids. The occurrence of two genes encoding for G1PDH and G3PDH, served to build up an evolution tree and the basis of our review focusing on the evolution of these two genes. Gene encoding for G3PDH in Eukarya may originate from G3PDH gene found in rare archaea indicating that archaea appeared earlier in the evolution tree than eukarya. Archaea and bacteria evolved probably separately, due to their distinct respective genes coding for G1PDH and G3PDH. The suggested hypothesis is that catalysis of homochiral G1P or G3P from DHAP are more efficient than those leading to racemic G1P and G3P, since there are no enzymes able to synthesize racemic G1P and G3P from DHAP. We propose that G1PDH or G3DPH, which are not “image mirror enzymes” but belonging to distinct family of proteins, emerged separately during evolution. They were probably selected for their efficient catalytic activities during evolution from large libraries of vesicles containing various biopolymers, including amino acids, carbohydrates, nucleic acids, lipids, and meteorite components to induce chemical imbalance.
ARTICLE | doi:10.20944/preprints202011.0709.v1
Subject: Life Sciences, Biochemistry Keywords: Sphingosine-1-phosphate receptor analogue; fingolimod phosphate; neuroprotection; mitochondrial damage; glycolytic pathway; pentose phosphate pathway; REDOX homeostasis.
Online: 30 November 2020 (08:31:50 CET)
Imbalance in the oxidative status in neurons, along with mitochondrial damage, are common characteristics in some neurodegenerative diseases. The maintenance in energy production is crucial to face and recover from the oxidative damage and the coexistence of different sources of energy production, such as mitochondrial and glycolytic ATP, allows faster adaptative mechanisms to situations of high energy demand and may help in the maintenance of neuronal function in stress situations. Fingolimod phosphate is a drug with neuroprotective and antioxidant actions, used in the treatment of Multiple Sclerosis. This work has been performed in a model of oxidative damage on neuronal cell cultures exposed to menadione, in presence or absence of fingolimod phosphate. We have studied the mitochondrial function and several pathways related with glucose metabolism, including oxidative, glycolytic and pentose phosphate in neuronal cells cultures. Our results showed a beneficial effect on neuronal survival probably based in the recovery of all, oxidative balance, glycolysis and pentose phosphate, promoted by fingolimod phosphate. These effects are mediated, at least in part by the interaction with its specific receptor. These actions would make this drug a potential tool to the treatment of neurodegenerative processes, either to slow progression or alleviate symptoms.
ARTICLE | doi:10.20944/preprints202102.0188.v1
Subject: Engineering, Automotive Engineering Keywords: Açaí; Residual Seeds; Pyrolysis; Bio-Oil; Distillation; Bio-gasoline; Bio-kerosene
Online: 8 February 2021 (11:10:32 CET)
The bio-oil obtained by pyrolysis of Açaí (Euterpe oleracea Mart.) seeds at 450 ºC, 1.0 atmosphere, in technical scale, submitted to fractional distillation to produce biofuels-like fractions. The distillation of bio-oil carried out in a laboratory distillation column (Vigreux) of 30 cm. The physical-chemistry properties (density, kinematic viscosity, acid value and refractive index) determined by official methods. The chemical functions present in distillation fractions determined by FT-IR and the chemical composition by GC-MS. The distillation of bio-oil yielded gasoline, light kerosene, and kerosene-like fuel fractions of 16.16, 19.56, and 41.89% (wt.), respectively. All the physical-chemistry properties (density, kinematic viscosity, acid value and refractive index) increase with boiling temperature. The gasoline-like fraction is composed by 64.0% (area.) hydrocarbons and 36.0% (area.) oxygenates, while light kerosene-like fraction by 66.67% (area.) hydrocarbons and 33.33% (area.) oxygenates, and kerosene-like fraction by 19.87% (area.) hydrocarbons and 81.13% (area.) oxygenates.
ARTICLE | doi:10.20944/preprints202102.0099.v1
Online: 4 February 2021 (09:15:34 CET)
Use of porous titanium (Ti) and Ti alloys in orthopedic implants or in light structures requires processing routes that could generate an as-much-as possible control in the pores amount, shape, size and connectivity. In this work, a colloidal approach to the processing of Ti porous structures by the inside foaming of a porogen into a gelled high solid content aqueous suspension of Ti powders, is presented. The prepared slurries contained different amounts of Methyl Cellulose (MC) as gelling agent (8, 10 and 12 g/L) and ammonium bicarbonate (BA) as porogen (15, 20, 25 wt. %). The gel-casted samples were heated at mild temperatures ranging (60, 70 and 80 °C) to promote the gelation and produce, at the same time, the porosity by the thermal decomposition of the ammonium bicarbonate. Different structures are obtained depending on the combination of the study variables
ARTICLE | doi:10.20944/preprints202007.0584.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Bio-organic fertilizer; Bio-chemical fertilizer; Grain yield; N-Fixer
Online: 24 July 2020 (13:46:30 CEST)
The aim of the present study was to assess the efficacy of All Cosmos Industries (ACI) bio-organic and bio-chemical fertilizers and ACI N-Fixer (N-Bio Booster) on the paddy yields based on the field trial plots at Langkat, Medan, Indonesia. This application of ACI bio-organic fertilizer (NPK 5/5/5) and ACI bio-chemical (NPK 15/15/15) fertilizer and ACI N-Fixer tests were conducted at the paddy farm at Langkat from May-October 2018. This study employed a factorial randomized complete block design which consisted of two factors, namely: Factor I with four types of fertilizers while Factor II consisted of two paddy varieties (Inpari 30 and Inpari 32). Overall, the filled grains in the ACI treatments are significantly (P< 0.05) higher than those in the control treatments that used Normal Chemical Compound NPK. Overall, total weight per meter² (368-617g) in ACI treatments are also significantly (P< 0.05) higher than those (319-371g) in the control treatments. At harvesting time at 105 days after transplanting, significantly higher (P< 0.05) colony counts (13-15 x 106 CFU/mL) (for ACI treatments), than those (8 x 106 CFU/mL) in the controls positively indicated higher total yields of paddy grains per hectare. It was found that the application of ACI bio-organic and bio-chemical fertilizers and ACI N-Fixer can improve paddy yields of the two rice varieties, between 16.4-38.2% (up to 5.75 MT/ha), in the field trial plots at Langkat. These commercial fertilizers play an imperative role in refining the soil fertility and thereby can increase the yield of rice production. Therefore, it is highly recommended that ACI bio-organic and ACI bio-chemical fertilizers and ACI N-Fixer (N-Bio Booster) can be employed to increase the paddy yield in this region.
REVIEW | doi:10.20944/preprints202109.0284.v1
Online: 16 September 2021 (13:29:23 CEST)
A single paragraph Arbuscular mycorrhizal fungi (AMF) establish symbiotic relationships with many crops. These soil microbiotas improve the soil fertility through the soil physical, chemical and biological properties. extending the root absorbing area. In return, the symbiont receives plant carbohydrates for the completion of its life cycle. AMF also helps plants to cope with biotic and abiotic stresses such as extreme temperature, heavy metal, diseases, and pathogens. For soil physical properties, the mechanisms used by AMF are the production of a glycoprotein, glomalin, which creates a high quality of soil macro-aggregations. These macro-aggregations control soil erosion, nutrients and organic matter losses. For soil chemical properties, AMF produce acids and an enzyme called phosphatase. This enzyme hydrolyzes the inorganic phosphorus and the rock phosphate (RP) hence making P available in the soil for plant uptake. AMF also are involved in soil nitrogen, carbon and trace element cycling. Regarding the biological component of the soil, AMF influence the composition, diversity and activity of microbial communities in the hydrosphere. They also work in synergy with others soil microorganisms to improve soil fertility, plant growth and resistance against some diseases. In this review, we present the contribution of AMF on soil fertility and importance in polluted soils.
ARTICLE | doi:10.20944/preprints202107.0342.v1
Subject: Materials Science, Biomaterials Keywords: phosphogypsum; REE; tailings pond; phosphate industry
Online: 15 July 2021 (09:10:36 CEST)
The majority of the phosphogypsum produced by a fertilizer plant in the Philippines is just stockpiled, which is considered a liability with no commercial prospects. It is important that we find use of this industrial waste by-product sooner than it becomes an environmental issue. Our study investigated the economic potential of the phosphogypsum by determining its rare earth elements (REE) composition. Phosphogypsum samples were collected from 2 m-depth trenches at 0.5 m intervals in 24 locations in the tailings ponds. ICPMS analysis of the phosphogypsum samples shows that the ponds have a mean Ʃ REE + Y concentrations of 266.15 mg kg-1. The individual REE concentrations are within the world average concentrations in phosphogypsum, although there is relative depletion of Yb, Tb, and Tm. There are huge variations in REE concentrations between the ponds, likely because these are produced from the processing of more than ten types of exported phosphate rocks since the start of operation of the fertilizer plant in 1980s. The major REE abundance is in the order of Y (26 %) > Ce (25 %) > La (16 %) > Nd (15 %). There is an estimated 66 M USD worth of REE oxides in the phosphogypsum ponds with a potential added value of 3.3 to 6.6 M USD for 1 to 2 Mt phosphogypsum produced annually at 50 % recovery rate. This study provides a comprehensive REE concentration and economic analyses of Philippine phosphogypsum produced from different types of imported phosphate rocks for potential REE extraction.
ARTICLE | doi:10.20944/preprints201801.0062.v1
Subject: Biology, Anatomy & Morphology Keywords: octacalcium phosphate; bone matrix gelatin; osteogenesis
Online: 9 January 2018 (03:14:28 CET)
Objective: Regeneration of bone defects remains a challenge for maxillofacial and reparative surgeons. The purpose of this histological study was to assess the osteogenic potential of octacalcium phosphate (OCP) and bone matrix gelatin (BMG) alone and in combination in artificially created mandibular bone defects in rats. The quality of the newly formed bone was also evaluated. Methods: Thirty-six male Sprague Dawley rats (6-8 weeks old with 120-150 g weight) were randomly divided into four groups. Defects (3 mm in diameter and 2 mm in depth) were created in the mandible of rats and filled with 6 mg of OCP, BMG or a combination of both (1/4 ratio), respectively. Defects were left unfilled in the control group. To assess osteoinduction and bone regeneration and determine the quality of the newly formed bone, tissue specimens were harvested at seven, 14, and 21 days post-implantation. The specimens were processed, stained with hematoxylin and eosin (H&E) and histologically analyzed under light microscopy. Results: In the experimental groups, new bone formation was initiated at the margins of defects from seventh day after implantation. At the end of the study period, the amount of the newly formed bone increased and the bone was relatively mature. Osteoinduction and new bone formation were greater in OCP/BMG group. In the control group, slight amount of new bone had been formed at the defect margins (next to host bone) on day 21. Conclusion: Combination of OCP/BMG may serve as an optimal biomaterial for treatment of mandibular bone defects.
Subject: Materials Science, Biomaterials Keywords: hydroxylapatite, oxyhydroxylapatite, oxyapatite, tricalcium phosphate, tetracalcium phosphate, Raman spectroscopy, MAS-CP NMR spectroscopy, 2D-HETCOR NMR spectroscopy.
Online: 5 August 2021 (11:06:47 CEST)
Functional osseoconductive coatings based on hydroxylapatite (HAp) and applied preferentially by atmospheric plasma spraying to medical implant surfaces are a mainstay of modern implantology. During contact with the hot plasma jet, HAp particles melt incongruently and undergo complex dehydration and decomposition reactions that alter their phase composition and crystallographic symmetry, and thus, the physical and biological properties of the coatings. Surface analytical methods such as laser-Raman and nuclear magnetic resonance (NMR) spectroscopies are useful tools to assess the structural changes of HAp imposed by heat treatment during their flight along the hot plasma jet. In this contribution, the controversial information on the existence or non-existence of oxyapatite, i.e. fully dehydrated HAp as a thermodynamically stable compound is highlighted.
ARTICLE | doi:10.20944/preprints202105.0363.v1
Subject: Materials Science, Biomaterials Keywords: Dental composite, Methacrylated calcium phosphate, translucency, Biomineralization
Online: 16 May 2021 (22:39:21 CEST)
The aim of this study was to synthesize and characterize a novel Methacrylate- functionalized Calcium Phosphate (MCP) used as a bioactive compound for innovative dental composites. The characterization was accomplished by Attenuated Total Reflectance Fourier-Transform Infrared Spectroscopy (ATR-FTIR), X-Ray Diffraction Analysis (XRDA), Scanning Electron Microscopy (SEM), and EnergyDispersive Spectroscopy (EDS). The incorporation of MCP as a bioactive filler in esthetic dental composite formulations and the ability of MCP containing dental composites to promote precipitation of hydroxyapatite (HAp) on the surfaces of those dental composites was explored. The translucency parameter, depth of cure, degree of conversion, ion release profile, and other physical properties of composites were studied with respect to the amount of MCP added to the composites. Composites containing 3 Wt.%, 6 Wt.%, and 20 Wt.% MCP were evaluated at 7, 14, and 21 days. The progress of surface precipitation of hydroxyapatite on MCP-containing dental composites was studied by systematically increasing the MCP content in the composite and the time of specimen storage in Dulbecco’s phosphate-buffered solution with calcium and magnesium. It was found that there was a direct correlation between the percentage of MCP in a composite formulation, the amount of time the specimen was stored in PBS, and the deposition of hydroxyapatite on the composite’s surface
ARTICLE | doi:10.20944/preprints202104.0263.v1
Subject: Biology, Anatomy & Morphology Keywords: Insoluble phosphate; Biosolubilizing; Biofertilizer; Actinobacteria; Sugar beet
Online: 9 April 2021 (13:34:01 CEST)
In this research, we isolated and characterized Streptomyces strains, endemic from sugar beet fields of the Beni-Mellal region, able to use natural rock phosphate (RP) and tricalcium phosphate (TCP), as sole phosphate source. Ten Streptomyces isolates yielded a comparable biomass in the presence of these two insoluble phosphate sources, indicating that they were able to extract similar amount of phosphorus (P) from the latter for their own growth. Interestingly, five strains released soluble P in large excess from TCP in their culture broth whereas only two strains, BP, related to Streptomyces bellus and BYC, related to Streptomyces enissocaesilis, released a higher or similar amount of soluble P from RP than from TCP, respectively. This indicated that the rate of P released from these insoluble phosphate sources exceeded its consumption rate for bacterial growth and that most strains solubilized TCP more efficiently than RP. Preliminary results suggested that the solubilization process of BYC, the most efficient RP and TCP solubilizing strain, involves both acidification of the medium and excretion of siderophores. Actinomycete strains possessing such interesting RP solubilizing abilities may constitute a novel kind of intrans beneficial for plant nutrition and more environmentally friendly than chemical fertilizers in current use.
Subject: Materials Science, Biomaterials Keywords: synthetic; xenogenous; nano-hydroxyapatita; beta-tricalcium phosphate
Online: 6 October 2020 (13:18:42 CEST)
Nowadays, we can observe a worldwide trend towards the development of synthetic biomaterials. Numerous researches have been carried out in order to better understand the cellular behavior involved in the inflammation and bone healing processes related to living tissues. The aim of this study is to evaluate the tissue behavior of two different types of biomaterials: synthetic nano-hydroxyapatite / beta-tricalcium phosphate and hydroxyapatite in non-critical bone defects in rat calvaria. Twenty four rats underwent surgery in which two 3 mm defects in each cavity were performed. The rats were divided into 2 groups: Group 1, using xenogen hydroxyapatite (Bio oss ™); Group 2, using synthetic nano-hydroxyapatite / beta-tricalcium phosphate (Blue Bone ™). Sixty days after the surgery, the calvaria bone defect was filled with biomaterial, the animals were sacrificed and marked with Masson's trichrome and PAS staining, and immunohistochemistry (TNF-α, MMP-9) and electron microscopy analyzes were performed. Histomorphometric analysis indicates a greater presence in the protein matrix in Group 2, in addition to higher levels of TNF-α, MMP-9. The ultrastructural analysis shows an association of material with fibroblasts in the tissue regeneration stage. Paired statistical data indicates that Blue Bone ™ can improve bone formation / remodeling when compared to biomaterials of xenogenous origin.
ARTICLE | doi:10.20944/preprints202009.0170.v1
Online: 8 September 2020 (04:54:58 CEST)
The Doig Phosphate Zone (DPZ) is a phosphate-bearing marine unit located at the base of the Doig Formation, in the Triassic section of the Western Canada Sedimentary Basin. The DPZ has a maximum thickness of 90 m and extends across northeastern British Columbia and western central Alberta. In this study we characterize the significance and interpret the origin of apatite in the DPZ, through mineralogical and geochemical analyses, thin section study and field emission-scanning electron microscopy. The occurrence of apatite in the DPZ is not evenly distributed, but restricted to discrete 10 to 20 cm thick beds, located near the base of the DPZ. Phosphorites are of two types: grainstones composed primarily of unconformity-bounded coated grains, and intraclastic phosphorites composed of detrital silt-sized grains and apatite coated grains in a cryptocrystalline phosphatic matrix. The phosphorite beds are records of stratigraphic condensation due to low detrital input during transgression. The erosionally-truncated phosphatic coated grains and intraclasts are interpreted to be a result of various phases of phosphatization, exhumation, erosion reworking, winnowing and redeposition in alternating quiescence and storms or bottom currents. The abundance of pyrite and chalcophile trace elements, as well as the low concentration of proxy elements for organic matter productivity and preservation, are further evidences of stratigraphic condensation, with sulfidic pore water development and extensive organic recycling promoted by biological activity during the long exposure times. The phosphorites were formed under oxygenated water conditions, as suggested by the depletion in Ce and presence of a diverse benthic fauna.
ARTICLE | doi:10.20944/preprints201901.0291.v1
Subject: Medicine & Pharmacology, Dentistry Keywords: Membranes; Polymer; Biocompatibility; Inflammatory cells; Calcium Phosphate
Online: 29 January 2019 (09:38:04 CET)
This study aimed to evaluate the physico-chemical properties, biocompatibility and bioabsorption of 3 different new membranes for bone guided regeneration (PLGA associated with hydroxyapatite and beta-TCP) with three thicknesses (200, 500 and 700 µm) implanted in mice subcutaneously. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and the quantification of Carbon, Hidrogen and Nitrogen were used to characterize the physico-chemical properties. One hundred Balb-C mice were divided into 5 experimental groups: Group 1 - Sham (without implantation); Group 2 - 200 μm; Group 3 - 500 μm; Group 4 - 700 μm; and Group 5 - Pratix®. Each group was subdivided into four experimental periods (7, 30, 60 and 90 days). Samples were collected and processed for histological and histomorphometrical evaluation. The membranes showed no moderate or severe tissue reactions in the experimental periods studied. The 500 μm membrane did not show tissue reaction for any experimental periods studied. The 200 μm membrane membranes began to exhibit fragmentation after 30- day, while the 500 and 700 µm membranes started the fragmentation at 90-day. All membranes studied were biocompatible, and the 500µm membrane showed the best results being a promissory membrane for bone guided regeneration.
CONCEPT PAPER | doi:10.20944/preprints201612.0111.v2
Subject: Materials Science, Surfaces, Coatings & Films Keywords: chemical phosphate coating; EIS; nano TiO2; TAFEL
Online: 23 December 2016 (10:23:24 CET)
The present study aims at deposition of zinc phosphate coatings with the incorporation of nano Titanium dioxide particles by chemical phosphating method. Zinc phosphate coatings were developed on low carbon steel by using nano TiO2 in the standard phosphating bath. The Coated low carbon steel samples were assessed for corrosion studies using electrochemical impedance spectroscopy and potentiodynamic polarisation techniques in 3.5% NaCl solution. Chemical composition of the coatings was analysed by energy dispersive X-ray spectroscopy (EDX). Significant variations in the coating weight, porosity and corrosion resistance were observed with the addition of nano TiO2 in the phosphating bath. Corrosion rate of nano TiO2 incorporated chemical phosphate coated samples was found to be 3.5 mpy which was 4 times less than the bare uncoated low carbon steel (~14 mpy). Electrochemical impedance spectroscopy studies revels in the reduction of porosity in nano TiO2 phosphate coated samples. It was found that nano TiO2 particles in the phosphating solution yielded phosphate coatings of higher coating weight, greater surface coverage and enhanced corrosion resistance than the normal zinc phosphate coatings (developed using normal phosphating bath).
ARTICLE | doi:10.20944/preprints202103.0266.v1
Subject: Materials Science, Biomaterials Keywords: diatomite; bio-composites; , mechanical properties; fractionation; purification of diatomaceous earth; bio-raw materials
Online: 9 March 2021 (11:44:48 CET)
The authors of this paper use an original method of diatomaceous earth fractionation, which allows for obtaining a filler with a specific particle size distribution. The method makes it possible to separate small, disintegrated and broken diatom frustules from those which maintained their original form in diatomaceous earth. The study covers a range of tests conducted to prove that such a separated diatomic fraction shows features different from the base diatomite used as an epoxy resin filler. We have examined mechanical properties of a series of diatomite/resin composites considering the weight fraction of diatoms and the parameters of the composite production process. The studied composites of Epidian 601 epoxy resin cross-linked with amine-based curing agent Z-1 contained 0 to 70% vol. of diatoms or diatomaceous earth. Samples were produced by casting into silicone moulds in vacuum degassing conditions and, alternatively, without degassing. The results have shown that the size and morphology of the filler based on diatomaceous earth affects mechanical and rheological properties of systems based on epoxy resin.
ARTICLE | doi:10.20944/preprints202109.0166.v1
Subject: Materials Science, Biomaterials Keywords: Octacalcium phosphate (OCP); Hydroxyapatite (HA); Biphasic calcium phosphate (BCP); Xeno-genic bone; Synthetic bone; Bone Regeneration; Phase conversion; Mineralization
Online: 9 September 2021 (08:23:32 CEST)
Octacalcium phosphate (OCP) is a precursor of biological apatite crystals that has attracted attention as a possible bone substitute. On the other hand, few studies have examined this material at the experimental level due to the limitations of OCP mass production. Recently, mass production technology of OCP was developed, and the launch of OCP bone substitutes is occurring. In this study, the bone regeneration capacity of OCP products was compared with two of the most clinically used materials: heat-treated bovine bone (BHA) and sintered biphasic calcium phosphate (BCP). Twelve rabbits were used, and defects in each tibia were filled with OCP, BHA, BCP, and left unfilled as control (CON). The tibias were harvested at 4 and 12 weeks, and 15 μm slides were prepared using the diamond grinding method after being embedded in resin. Histological and histomorphometric analyses were performed to evaluate the bone regeneration ability and mechanism. The OCP showed significantly higher resorption and new bone formation in both periods analysed (p<0.05). Overall, OCP bone substitutes can enhance bone regeneration significantly by activating osteoblasts and a rapid phase transition of OCP crystals to biological apatite crystals (mineralisation), as well as providing additional space for new bone formation by rapid resorption.
ARTICLE | doi:10.20944/preprints202103.0046.v1
Online: 2 March 2021 (09:10:51 CET)
Application of native PGPR as bio inoculant is an alternative sustainable agricultural practice to enhance crop productivity, grain quality, and soil fertility. In this view, a study was to examine the effect of either individual or consortium PGPR inoculation on growth, yield, and grain nutrient uptake of two teff varieties. The pot experiment was carried out in (CRD) three replication and 10 treatments. The PGPR inoculants used in this study were Pseudomonas fluorescens biotype G, Enterobacter cloacae ss disolvens, and Serratia marcescens ss marcescen and their consortium. Dukem and Magna varieties were used in this study. The results of the analysis of variance showed significant differences (P ≤ 0.001) among the treatment and most of the agronomic traits except number of fertile tillers and also significant different (P ≤ 0.01) for grain P and N uptake. The variety was significantly affected grain Mg, Zn and Fe uptake at 5 % probability level and did not significantly influence all agronomic traits of the two varieties. Furthermore, interaction effects of two factors (TM*VT) were significant differences (P ≤ 0.05) for plant height and panicle length. Individual treatments mean comparison results showed that inoculation of native PGPR consortium significantly affected most of the PGP traits at (P ≤ 0.05). The maximum traits like plant height (189cm), panicle length (66.7cm), shoot dry biomass (9.98g), root dry biomass (2.90g) and grain yield per plant (4.55g) were observed from Dz-01-196. It could be concluded that the consortium of native PGPR inoculants for plant growth, yield and grain nutrient uptake improvement performed better than their individual strain.
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: biodegradation; bio-derived polymer; composites
Online: 5 August 2019 (04:29:57 CEST)
Composites with HDPE and PLA matrix have been tested to analyse the effect of natural fillers (wood flour, recycled waste paper and a mix of both fillers) and temperature on polymer degradation. Composting tests have been performed in both mesophilic (35°C) and thermophilic (58°C) conditions. Degradation development has been evaluated through mass variation, TGA and DSC. HDPE, as expected, did not display any relevant variation, confirming its stability under our composting conditions. PLA is sensibly influenced by temperature and humidity, with higher reduction of Mw when composting is performed at 58°C. Natural fillers seem to influence degradation process of composites, already at 35°C. In fact, degradation of fillers at 35°C allows a mass reduction during composting of composites, while neat PLA do not display any variation.
ARTICLE | doi:10.20944/preprints202208.0438.v1
Subject: Engineering, Energy & Fuel Technology Keywords: MHSW; Organic fraction from MHSW, Thermal processing; Bio-char characterization; Bio-oil: Liquid hydrocarbons
Online: 26 August 2022 (03:16:54 CEST)
This work aims to investigate the effect of process temperature and catalyst content by pyrolysis and thermal catalytic cracking of (organic matter + paper) fraction from municipal household solid waste (MHSW) on the yields of reaction products (bio-oil, bio-char, H2O, and gas), acid value and chemical composition of bio-oils, and characterization of bio-chars, in laboratory scale. The collecting sectors of MHSW in the municipality of Belém-Pará-Brazil were chosen based on geographic and socio-economic database. The MHSW collected and transported to the segregation area. The gravimetric analysis of MHSW carried out and the fractions (Paper, Cardboard, Tetra Pack, Hard Plastic, Soft Plastic, Metal, Glass, Organic Matter, and Inert) separated. The selected organic matter and paper submitted to pre-treatment of crushing, drying, and sieving. The experiments carried out at 400, 450, and 475 °C and 1.0 atmosphere, and at 475 °C and 1.0 atmosphere, using 5.0, 10.0, and 15.0% (wt.) Ca(OH)2, in batch mode. The bio-oil characterized for acid value. The chemical functions present in bio-oil identified by FT-IR and the composition by GC-MS. The bio-char characterized by SEM, FT-IR and XRD. The variance in mass (wt.%) for organic fraction of municipal household solid waste, between 56.21 and 67.45% (wt.), lies with the interval of 56% (wt.) and 64% (wt.) of OFMHSW for middle and low income countries. The pyrolysis of MHSW fraction (organic matter + paper) show bio-oil yields between 2.63 and 9.41% (wt.), aqueous phase yields between 28.58 and 35.08% (wt.), solid phase yields between 35.29 and 45.75% (wt.), and gas yields between 16.54 and 26.72% (wt.). The bio-oil yield increases with pyrolysis temperature. For the catalytic cracking, the bio-oil and gas yields increase slightly with CaO content, while that of bio-char decreases, and the H2O phase remains constant. The GC-MS of liquid reaction products identified the presence of hydrocarbons (alkanes, alkenes, alkynes, cycloalkanes, and aromatics) and oxygenates (carboxylic acids, ketones, esters, alcohols, phenols, and aldehydes), as well as compounds containing nitrogen, including amides and amines. The acidity of bio-oil decreases with increasing process temperature and with aid Ca(OH)2 as catalyst. The concentration of hydrocarbons in bio-oil increases with increasing Ca(OH)2-to-MHSW fraction ratio due to the catalytic deoxygenation of fatty acids molecules, by means of de-carboxylation/de-carbonylation, producing aliphatic and aromatic hydrocarbons.
ARTICLE | doi:10.20944/preprints202011.0349.v1
Subject: Medicine & Pharmacology, Allergology Keywords: mesenchymal stem cell; beta-tricalcium phosphate; hydroxyapatite; osteogenesis.
Online: 12 November 2020 (13:16:15 CET)
Bone innate ability to repair without scaring is surpassed by major bone damage. Current gold-standard strategies do not achieve a full recovery of bone biomechanical properties. To bypass these limitations, tissue engineering techniques based on hybrid materials made up of osteoprogenitor cells, like mesenchymal stem cells (MSCs), and bioactive ceramic scaffolds, like calcium phosphate-based (CaPs), are promising. Biological properties of the MSCs, are influenced by the tissue source. The aim of this study is to define the MSC source and construct (MSC and scaffold combination) most interesting for its clinical application in bone regeneration. iTRAQ generated the hypothesis that anatomical proximity to bone has a direct effect on MSC phenotype. MSCs were isolated from adipose tissue, bone marrow and dental pulp. MSCs were cultured both on plastic surface and on CaPs (hydroxyapatite and β-tricalcium phosphate) to compare their biological features. On plastic, MSCs isolated from dental pulp (DPSCs) were the MSCs with the highest proliferation capacity and the greatest osteogenic potential. On both CaPs, DPSCs are the MSCs with the greatest capacity to colonize bioceramics. Furthermore, results show a trend for DPSCs are the MSCs with the most robust increase in the ALP activity. We propose DPSCs as a suitable MSCs for bone regeneration cell-based strategies.What do you want to do ?New mailCopy
ARTICLE | doi:10.20944/preprints201807.0288.v1
Subject: Materials Science, Biomaterials Keywords: calcium phosphate cement; methylcellulose; 3D plotting; support; hydroxyapatite
Online: 16 July 2018 (12:55:42 CEST)
3D plotting is an additive manufacturing technology enabling biofabrication, thus the integration of cells or biologically sensitive proteins or growth factors into the manufacturing process. However, most (bio-)inks developed for 3D plotting were not shown to be processed into clinical relevant geometries comprising critical overhangs and cavities, which would collapse without a sufficient support material. Herein, we have developed a support hydrogel ink based on methylcellulose (mc), which is able to act as support as long as the co-plotted main structure is not stable. Therefore, 6 w/v %, 8 w/v % and 10 w/v % mc were allowed to swell in water, resulting in viscous inks, which were characterized for their rheological and extrusion properties. The successful usage of 10 w/v % mc as support ink was proven by multichannel plotting of the support together with a plottable calcium phosphate cement (CPC) acting as main structure. CPC scaffolds displaying critical overhangs or a large central cavity could be plotted accurately with the newly developed mc support ink. The dissolution properties of mc allowed complete removal of the gel without residuals, once CPC setting was finished. Finally, we fabricated a scaphoid bone model by computed tomography data acquisition and co-extrusion of CPC and the mc support hydrogel.
BRIEF REPORT | doi:10.20944/preprints202203.0104.v3
Subject: Biology, Plant Sciences Keywords: Calvin-Benson cycle; carbon metabolism; CO2 fertilisation; glucose-6-phosphate shunt; hydrogen stable isotopes; oxidative pentose phosphate pathway; photosynthesis; respiration
Online: 16 May 2022 (12:14:30 CEST)
Despite significant research efforts, the question of whether rising atmospheric CO2 concentrations (Ca) affect leaf respiration remains unanswered. Here, I reanalyse published hydrogen isotope abundances in starch glucose of sunflower leaves. I report that, as Ca increases from 450 to 1500 ppm, respiration by the oxidative pentose phosphate pathway in chloroplasts increases from 0 to ≈ 5% relative to net carbon assimilation. This is consistent with known regulatory properties of the pathway. Summarising recent reports of metabolic fluxes in plant leaves, a picture emerges in which mitochondrial processes are distinctly less important for overall respiration than the oxidative pentose phosphate pathways in chloroplasts and the cytosol. Regulatory properties of these pathways are consistent with observations of lower-than-expected stimulations of photosynthesis in response to increasing Ca. Reported advances in understanding leaf respiratory mechanisms may enable modelling and prediction of respiration effects (inter alia) on biosphere-atmosphere CO2 exchange and plant performance under climate change.
BRIEF REPORT | doi:10.20944/preprints202011.0320.v1
Online: 10 November 2020 (15:05:24 CET)
This study evaluates the production of biohydrogen from agro industrial waste. The worldwide energy demand is increasing exponentially and the reserves of fossil fuels are depleting, the combustion of fossil fuels has the effect on environment because of CO2 emission. Hydrogen generation market size is forecast to cross 180 billion by 2024, according to a new research report by global market. For the production of biohydrogen. we had chosen groundnut shell as our source, using Tween80 as a surfactant we had undergone pre-treatment studies for (10min,20min,30min,40min,50min) we had estimated the content of cellulose, protein, carbohydrates at (1%,2%,3%,4%,5%) and obtained the optimum value in the form of graph. The production of hydrogen is done by using the rumen fluid of the cow and the quantity of the hydrogen produced by this process is identified by using the analytical instrument Gas Chromatography.
ARTICLE | doi:10.20944/preprints202009.0314.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: Incremental Forming; Bio-composites; Hot Formability
Online: 14 September 2020 (00:25:46 CEST)
The use of biodegradable materials has a growing field of application due to environmental concerns, however, scientific research on incremental forming using biomaterials is scarce. Thus, this study focuses on the single point incremental forming (SPIF) process applied to a composite sheet that combines a biodegradable thermoplastic matrix (Solanyl) reinforced with natural fibres (flax). The influence of the process parameters on the final geometry is determined, evaluating the effect of the following factors: step depth, wall angle and temperature reached during the process. Additionally, a heated aqueous medium is incorporated which facilitates the formability of the composite sheets. This method is especially useful for materials that have poor formability at room temperature. The benefits of using controlled heat include the reduction of formation forces applied to the plate, improved accuracy due to the reduction of elastic recovery, and the manipulation of the samples remarkably close to the glass transition temperatures. Through this experimental study with the variables analysed, a maximum shaping depth of 310 mm is obtained. These results confirm that the single point shaping used with bioplastic materials is possible and has positive outcomes for incremental forming.
REVIEW | doi:10.20944/preprints202006.0307.v1
Subject: Medicine & Pharmacology, Dentistry Keywords: bio-aerosol; reduction; procedures; dentistry; review
Online: 25 June 2020 (12:24:48 CEST)
Microbe laden air particles, known as bio-aerosols, are routinely generated, in clinical dentistry due to the operative instrumentation within a milieu rich in salivary organisms. As the major mode of transmission of SARS-CoV-2 appears to be airborne aerosols and droplets, there has been an intense focus on such aerosol generating procedures (AGP). As there has been no systematic reviews on the efficacy of bio-aerosol reducing measure in dentistry, the objective of this systematic review was to evaluate the literature on three major AGPs, rubber dam application, pre-procedural oral rinse, and high-volume evacuation (HVE) aimed at reducing dental bio-aerosols. Method: PubMed via Ovid MEDLINE, EBSCO host, Cochrane Library, and Web of Science databases between January 01, 1985, and April 30, 2020, were searched.Results: A total of 156 records in the English language literature were identified, of which 17 clinical studies with 724 patients were included in the final analyses. The eligible reviewed articles revealed the inadequacy of the afore mentioned three principal AGPs used in contemporary dental practice to minimise bio-aerosols. HVE appears to be the most efficacious method, although no single approach provides total elimination of bio-aerosols. Conclusion:This, the first systematic review on methods of controlling bio-aerosols in dental operatory settings, indicates that employing combination strategies of rubber dam, with a pre-procedural antimicrobial oral rinse, and HVE can significantly minimize bio-aerosols. As the quality of the currently available data on dental bio-aerosols are rather poor, further, controlled, multi-centre studies are essential to address this critical issue.
ARTICLE | doi:10.20944/preprints202003.0253.v1
Online: 16 March 2020 (01:16:25 CET)
Surface Plasmon Resonance (SPR) is an attracting property of certain transition metals when they are synthesized in nano-range giving rise to promising optical applications. However, most SPR and associated applications are limited to the noble metal nanoparticles, which limits their potential due to high production cost. We report surface plasmon resonance in copper-copper oxide core-shell quantum dots synthesized via chemical route studied by using UV-Visible spectrophotometry. Tuning of the plasmonic resonance with respect to the particle diameter is achieved by an inexpensive all chemical route. Photoluminescence measurements also support the data. This size reduction leads to remarkable changes in its optical response as compared to the bulk metal. The results point towards applications of these materials in tunable SPR based biosensors.
ARTICLE | doi:10.20944/preprints202112.0319.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Waste water; Phosphate co-product; Adsorption; Red Acid 52
Online: 21 December 2021 (09:15:16 CET)
Water is essential for all living things however its pain has become serious. Many industrial activities cause its pollution by the release of polluting byproduct. Waste water treatment is hence necessary. In this context, the waste water of the textile industry containing Red Acid 52 was treated by the solid waste of the washed natural phosphate byproduct. Natural phosphate was also studied. The solid materials were first characterized by chemical analysis, Fourier Transform Infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The phosphate materials were after that, tested in the adsorption of the Red Acid 52. The experimental data indicated that the phosphate waste rock allowed the removal of Red Acid 52. Its maximum retention capacity attained 18.4 mg.g-1. Calcinations of materials inhibits the removal capacity found reduced by 60 to 70%. The adsorption kinetics of the Red Acid 52 on the material is well described by the pseudo second order model while the adsorption isotherms are identified by the Langmuir model. Hereafter, the thermodynamic study revealed that the adsorption process is spontaneous and exothermic. Keywords: Waste water, Phosphate co-product, Adsorption, Red Acid 52.
ARTICLE | doi:10.20944/preprints201809.0512.v1
Subject: Medicine & Pharmacology, Nutrition Keywords: parenteral nutrition, neonatal solution; calcium; phosphate; organic; inorganic; precipitation;
Online: 26 September 2018 (13:57:18 CEST)
The aim of the study was to determine the maximum safe concentration of calcium and phosphate in neonatal parenteral nutrition (PN) solutions when various combinations of inorganic and organic salts are applied. Twelve PN solutions for neonatal use were aseptically prepared. Increasing concentration of inorganic and organic calcium and phosphate were added to the standard formulas. Each admixture was separately tested according to following conditions; after mixing, 37°C for 24 h, and maximum safe combination of calcium and phosphate were stored at 4°C for 30 days and followed by 24 h at 37°C. Visual inspections against a black and white contrast background, microscopic observation of undiluted PN solutions as well as the membrane filter after filtration of the PN solution, pH evaluation, and spectrophotometry at 600 nm were examined in triplicate. Safe maximum concentration of organic and inorganic calcium and phosphate was proposed individually for each composition of parenteral nutrition solutions. Surprisingly organic calcium with organic phosphate showed precipitation but over the therapeutic range. The protective effect of amino acid was observed and higher concentrations of calcium and phosphate were free of precipitation.
ARTICLE | doi:10.20944/preprints202006.0359.v1
Subject: Arts & Humanities, Music Studies Keywords: Scambi; Bio-Art; Bio-Music; music; counterpoint; process composition; dynamic programming; Needleman-Wunsch algorithm; global alignment
Online: 30 June 2020 (08:17:20 CEST)
The Needleman-Wunsch process is a classic tool in bioinformatics, being a dynamic programming algorithm that performs a pairwise alignment of two input biological sequences, either protein or nucleic acid. A distance matrix between the tokens used in the sequences is also required as input. The distance matrix is used to generate a positional pairwise similarity matrix between the input sequences, which is in turn used to generate a dynamic programming matrix. The best path through the dynamic programming matrix is navigated using a traceback procedure that maximises similarity, inserting gaps as necessary. Needleman-Wunsch can align both nucleic acids or proteins, which use alphabets of size 4 and 20 tokens respectively. It can also be applied to any other kind of sequence where distance matrices can be specified. Here, we apply it to chains of Pousseur’s Scambi electronic music fragments, of which there are 32, and which Pousseur categorised by their sonic properties, thus permitting the consecutive construction of distance, similarity and dynamic programming matrices. Traceback through the dynamic programming matrix thus produces contrapuntal duet compositions in which two Scambi chains are played in the maximally euphonious manner, providing also an illustration of the principles of biological sequence alignment in sound.
ARTICLE | doi:10.20944/preprints201807.0429.v1
Subject: Social Sciences, Economics Keywords: biomass, bio-energy, bio-chemicals, advanced technologies, agricultural production, trade, land use, economic modelling, MAGNET model
Online: 23 July 2018 (15:08:09 CEST)
As the EU is moving towards a low carbon economy and seeks to further develop its renewable energy policy, this paper quantitatively investigates the impact of plausible energy market reforms from the perspective of bio-renewables. Employing a state-of-the-art biobased variant of a computable general equilibrium model, this study assesses the perceived medium-term benefits, risks and trade-offs which arise from an advanced biofuels plan, two exploratory scenarios of a more 'sustainable' conventional biofuels plan and a 'no-mandate' scenario. Consistent with more recent studies, none of the scenarios considered present significant challenges to EU food-security or agricultural land usage. An illustrative advanced biofuels plan simulation requires non-trivial public support to implement whilst a degree of competition for biomass with (high-value) advanced biomass material industries is observed. On the other hand, it significantly alleviates land use pressures, whilst lignocellulose biomass prices are not expected to increase to unsustainable levels. Clearly, these observations are subject to assumptions on technological change, sustainable biomass limits, expected trends in fossil fuel prices and EU access to third-country trade. With these same caveats in mind, the switch to increased bioethanol production does not result in significant market tensions in biomass markets.
ARTICLE | doi:10.20944/preprints202002.0297.v1
Subject: Chemistry, Electrochemistry Keywords: light alloys; magnesium; corrosion; vanadate; phosphate; fluoride; inhibition; conversion coating
Online: 21 February 2020 (02:21:19 CET)
The anodic polarization response of magnesium alloy AZ31 was characterized during exposure to aerated 0.1M NaCl solutions with millimolar additions of NaVO3, Na3PO4, Na2HPO4, NaF and various pairings to assess their ability to inhibit corrosion kinetics and retard localized corrosion. Each of the candidate inhibitors reduced the corrosion rate of the alloy to some degree. A Na3PO4 - NaVO3 pair produced a powerful inhibiting response decreasing the corrosion rate to about 10-7 A/cm2, which was two orders of magnitude lower than the uninhibited control case. A Bliss Independence assessment indicated that this inhibitor pair acted synergistically. A Na2HPO4 - NaVO3 pair reduced the corrosion rate to 10-6 A/cm2 but was not assessed to be acting synergistically. The NaVO3 - NaF pair did not reduce the corrosion rate significantly compared to the control case and was an antagonistic pairing. SEM imaging showed film formation due to exposure, which appears to be the origins of the observed inhibition. The resistance to localized corrosion was assessed as the difference in the breakdown potential and the corrosion potential with larger values indicating a lower probability of localized corrosion during free corrosion exposures. Effects of the inhibitors on this characteristic were mixed, but each of the inhibitor pairs yielded potential differences in excess of 100mV. A conceptual conversion coating process based on a mixture of vanadate and phosphate compounds were demonstrated. A fluoride-bearing formulation produced coatings whose total impedance was increased by a factor or 2 compared to an uncoated control. A fluoride-free formulation produced coatings whose corrosion resistance was increased by more than a factor of 3.
ARTICLE | doi:10.20944/preprints201909.0317.v1
Subject: Materials Science, Nanotechnology Keywords: consolidation; sandstone; alkoxide consolidants; diammonium hydrogen phosphate; accelerated weathering; durability
Online: 28 September 2019 (15:12:05 CEST)
To achieve efficient and durable consolidation of weathered sandstone, the selection of a suitable consolidant is essential. To reasonably assess the suitability of different formulations, it is fundamental to compare their performance as a consolidant within a substrate, which reliably models the properties of deteriorated material. As a test substrate, the sandstone from quarries in Mšené in central Bohemia was selected, for its developed porosity and relatively low mechanical strength. To obtain relevant comparison of their application potential, both commercial (Remmers KSE OH and Surfapore) and self-developed consolidants were included. To test the long-term stability of each consolidant, the stone was subjected to accelerated weathering. The characterization of texture properties was based on the physical sorption of nitrogen and krypton, mercury intrusion porosimetry and water uptake. While the mechanical properties in microscale were determined by nanoindentation, the mechanical strength in macroscale before and after consolidation was measured by drilling resistance. Both commercial exhibited good mechanical performance with reasonable durability. The performance of our developed samples was comparable or, in some cases, superior. Very interesting were the consolidants containing TiO2 and ZnO nanoparticles, the former exhibiting comparable degree of consolidation and durability as commercial ones, with additional photocatalytic function, the latter unusually high increase in the mechanical strength, even after the weathering test. The diammonium hydrogen phosphate based consolidant showed exceptional durability in the weathering test, which makes it a promising product not only for carbonate but also sandstone materials.
REVIEW | doi:10.20944/preprints202302.0063.v1
Subject: Life Sciences, Biotechnology Keywords: Microalgae; Bio acids; Phytohormones; Medium Culture; Stress
Online: 3 February 2023 (08:45:13 CET)
Natural astaxanthin is a precious substance obtained from some organisms such as microalgae. This plant has many benefits for humans, so research into its cost-effective and economical production has recently increased. For this purpose, some methods such as the use of different culture media, gene engineering, different stresses, nanoparticles, bio acids, and phytohormones are important. Accordingly, this review study was conducted to demonstrate the effect of the factors mentioned above for the high production of astaxanthin in microalgae, especially Haematococcus pluvialis (H.p).
REVIEW | doi:10.20944/preprints202207.0136.v1
Subject: Engineering, Energy & Fuel Technology Keywords: Bio-briquettes; Heating values; lignocellulosic composition; Binders
Online: 8 July 2022 (07:54:23 CEST)
Briquetting of biomass is an ideal technique for improvising both its volumetric and net energy density; besides, serving as an effective means for reducing pollution. In general, numerous biomass and organic by-products are discarded as wastes, citing their non-edibility, composition of chemical compounds present in their raw form, in addition to their zero usage value. Yet, these biomass wastes hold significant heating values, which promote them into promising solid biofuels, either in their existing or pre-treated form. Accordingly, this review article discusses about the various biomasses used as raw feedstock for briquetting, besides summarising the works carried out in relevance to their respective briquettes. In addition, proximate and lignocellulosic composition of these biomasses, and their pre-treatment techniques followed to prepare them for briquetting, have also been discussed. This study suggested that the heating value of biomasses ranged between 10-20 MJ/kg, whilst, their briquettes reported between 15 and 25 MJ/kg; thereby citing their potential as viable replacement for existing fossil coals. Besides, factors affecting different thermal and physicochemical properties of these briquettes have also been studied and concluded that these properties play a crucial role in deciding the overall quality of the briquettes. Ultimately, this study proposed that any biomass with good calorific value and lignin content can be processed into briquettes with good strength and durability; however, the choice of biomass will also be accounted for by its availability, geographical distribution, and handleability.
REVIEW | doi:10.20944/preprints201811.0272.v1
Subject: Biology, Plant Sciences Keywords: saponin-containing plants; cleansing plants; bio-surfactant
Online: 12 November 2018 (09:07:26 CET)
The natural forests of Northern Thailand are the mother source of many utilisable natural products because of their diverse flora and fauna. Among many plant species found within Northern Thai forests, detergent plants are known for its distinctive cleansing properties. Several local species of detergent plants in Thailand are traditionally used by the locals and indigenous people. However, these plants may become extinct because their habitats have been replaced by industrial agriculture, and their uses have been replaced by chemically synthesised detergents. Researchers need to study and communicate the biology, phytochemistry, and the importance of these plants to conserve natural biodiversity of Northern Thailand. Of many utilisable detergent phytochemicals, natural saponins are known as bio-surfactant and foaming agents. Their physiochemical and biological properties feature structural diversity, which leads to many industrial applications. In this review, we explained the term “detergent” from the physiological mechanism perspective and the detergent effects of saponin. We also compiled a list of Thai local plants with cleansing properties focusing on the saponin-containing plants. Future studies should investigate information relative to plant environment, ethnobotanical data and bioactive compound content of these plants. The knowledge acquired from this study will promote the maintenance of the local biodiversity and the conservation of the detergent plant species found in Thailand.
ARTICLE | doi:10.20944/preprints201810.0046.v1
Subject: Life Sciences, Biotechnology Keywords: Bio-disinfection, G. latifolium, Water, Z. zanthoxyloides.
Online: 3 October 2018 (12:53:16 CEST)
Water and sanitation facilities in sub-Saharan Africa and Africa in general are appalling and for the most part absent. Progress continues with respect to the development of plant materials as potent adsorbents, disinfectants, coagulants, flocculants, wetland species and lots more as substitutes for the dangerous chemical disinfectants. This research presents the potential of phyto-active components of Zanthoxylum zanthoxyloides and Gongronema latifolium as effective biocides against water microbial contaminants. Dry powder of Zanthoxylum zanthoxyloides and Gongronema latifolium were extracted and prepared into different concentrations with ethyl acetate and chloroform, ranging from 25 to 500 mg/ml. These fractions were then examined for antimicrobial activities against inherent bacterial and fungal water contaminants using disc diffusion assay. Fractions were afterwards screened for phytochemical active compounds using standard methods. Crude extracts of the different plant examined selectively comprise saponins, tannins, reducing sugars, anthraquinones, flavonoids, terpenoids, phlobatanins and alkaloids. All plant extracts showed broad spectrum antibiosis against selected gram positive and gram negative bacteria including E. coli, P. aeruginosa, Klebsiella sp, S. pneumoniae and B. cereus, as well as tested fungi, including A. niger, A. flavus, Trichoderma sp and Candida sp. While all extracts exhibited maximum antibiosis at 500 mg/ml, the chloroform extracts compared well than ethyl acetate extracts. The overall results revealed that antimicrobial activities of the plant extracts are dose dependent with comparative activity greater than that of commercial antibiotics at the concentration of extracts tested. E.coli was the most susceptible microbial isolate tested and represents the potential of the extract against a group of coliform which are important indicators of microbial pollution in water. Other microbial isolates also recorded sensitivity to extracts tested at varying degrees. The findings indicate that microbes tested were mostly susceptible to chloroform extract of Z. zanthoxyloides and G. latifolium except for the activity of ethyl acetate extract of Z. zanthoxyloide against E.coli. Results of phytochemical screening of the extract also showed the varied presence of alkaloids, saponins, tannins, flavonoids, terpenoids and anthraquinones The results indicated that plant materials investigated can be developed as effective biocides against water microbial contaminants
Subject: Life Sciences, Biochemistry Keywords: Wheat; yield; triple-super-phosphate; sulfur; nitrogen; micro-dosing, precision-farming
Online: 21 July 2021 (08:22:32 CEST)
This research was specifically aimed at assessing the influence of sulfur in triple-super phosphate (TSP) on wheat yield. From the results, wheat showed response to sulfur (S) from gypsum (in 67%); and nitrogen (N) from urea in about 100% (of 24 sites). Based on this N was found to be the most limiting element to wheat production followed by sulfur, and then by phosphorus. TSP is tested to contain agronomically up to 2-6% by weight of S. However, wheat didn’t show response to S impurity supplied in the form of TSP. Though, not statistically significant, it is observed that there have always been yield increments by certain percent due to S from TSP in 8 out of 10 target sites, which is depicted in the increasing trends of yield response curves. From this it is learnt that, the benefits of the accidental/incidental application of such high analysis fertilizers can be many-folds in the quality attributes of wheat, if the soils of such investigation at the same time would contain significant amount of organic matter (OM). Indeed, such analysis would be vital in varietal specific nutrient requirement studies in precision-farming and/or in categorizing soils into fertility gradients and fertilizer recommendation domains.
Subject: Life Sciences, Other Keywords: Bio-image Analysis; Core-Facility; Sustainability; FAIR-principles
Online: 30 January 2023 (10:03:53 CET)
Recent advances in microscopy imaging and image analysis motivate more and more institutes world-wide to establish dedicated core-facilities for bio-image analysis. To maximize the benefits research groups at these institutes gain from their core-facilities, they should be established to fit well into their respective environment. In this article, we introduce common collaborator requests and corresponding potential services core-facilities can offer. We also discuss potential conflicts of interests between the targeted missions and implementations of services to guide decision makers and core-facility founders to circumvent common pitfalls.
ARTICLE | doi:10.20944/preprints202203.0160.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: Bio-Sensing; inter-symbol interference; molecular communication; synchronisation
Online: 11 March 2022 (04:43:21 CET)
Molecular communication (MC) is a promising bio-inspired paradigm for exchanging molecule information among nanomachines. This paper proposes a synchronisation-assist photolysis MC system that aims to transmit the bio-sensing signal of the tumour microenvironment, facilitated by mitigating redundant molecules for improved bit error rate (BER) performance. Benefits from bio-compatible MC, biosensors could transmit bio-sensing signals of the tumour in $vivo$ instead of converting them to electrical signals. Due to diffusion motion's slow and stochastic nature, inter-symbol interference (ISI), resulting from previous symbols' residual information molecules, inevitably occurs in diffusion-based MC. ISI is one of the challenges in diffusion-based MC, which significantly impacts signal detection. Inspired by on-off keying (OOK) modulation, the proposed modulation implements a switch of molecules and light alternatively. The light emitted is triggered by a synchronisation signal, and the photolysis reactions could reduce the redundant molecules. An expression for the relevant channel impulse response (CIR) is derived from a hybrid channel model of diffusion and photolysis-reaction. This paper implements the maximum posterior estimation scheme to find the optimal decision threshold and analysis the BER performance in terms of different time intervals of the system. Numerical simulations demonstrate that the proposed method can improve the channel capacity and BER performance. We believe that our work may pave the way for MC application in bio-sensing.
ARTICLE | doi:10.20944/preprints201912.0273.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Capsicum annuum; flavonoids; fluorescence monitoring; bio-waste utilization
Online: 20 December 2019 (11:05:22 CET)
The green biomass of horticultural plants contains valuable secondary metabolites (SM) which can potentially be extracted and sold. When exposed to stress, plants accumulate higher amounts of these SMs, making the extraction and commercialization even more attractive. We evaluated the potential for accumulating of the flavones cynaroside and graveobioside A in leaves of two bell pepper cultivars (Mavras and Stayer) when exposed to salt stress (100 mM NaCl), UVA/B excitation (UVA 4-5 W/m²; UVB 10-14 W/m² for 3 hours per day) or a combination of both stressors. HPLC analyses proved the enhanced accumulation of both metabolites under stress conditions. Cynaroside accumulation is effectively triggered by high-UV stress, whereas graveobioside A contents increase under salt stress. Highest contents were observed in plants exposed to combined stress. Effects of stress on overall plant performance differed significantly between treatments, with least negative impact on aboveground biomass found for high-UV stressed plants. The usage of two non-destructive instruments (Dualex and Multiplex) allowed us to gain insights in ontogenetical effects at the leaf level and temporal development of SM contents over time. Indices provided by those devices correlate fairly with amounts detected via HPLC (Cynaroside: R2 = 0.46 – 0.66; Graveobioside A: R2 = 0.51 – 0.71). The concentrations of both metabolites tend to decrease at leaf level during the ontogenetical development even under stress conditions. High-UV stress is a promising tool for enriching plant leaves with valuable SM without major effects on plant biomass. All data is available online .
ARTICLE | doi:10.20944/preprints201904.0268.v1
Subject: Social Sciences, Economics Keywords: intellectual capital; sustainability; harness; bio-economy; global crisis
Online: 24 April 2019 (12:10:55 CEST)
Bio-economy is a major area of the strategy that can afford the European Union to achieve growth: (i) smart, through the development of knowledge and innovation; and (ii) sustainable, based on a greener, more efficient economy in resource management. We believe that the progress of bio-economy cannot be achieved without the harnessing of intellectual capital. Our research aimed to emphasize the benefits of the dynamics of the intellectual capital growth on the evolution of the bio-economy. Thus, the information published by Eurostat (European Statistic Institute) during a period spanning seven years (2011-2018) was used to assess the influence exerted by the conduct of the harness of intellectual capital related to sustainability as well as for the reporting of indicators relevant to appreciating an economic progress and sustainability (renewable waste material, share of renewable energy and energy intensity of the economy). The ultimate goal was represented by the generation of a regression model to see what factor influences mostly the progress of the bio-economy at European and Romanian level. Significant dependency relationships were identified. The results remain robust even after the introduction of certain control variables, such as gross domestic product rate, food production, population growth, urbanization growth and inflation. Our paper sets out to contribute to expanding the specialty literature by highlighting the involvement of intellectual capital as a factor in optimizing sustainability growth and, at a methodological level, by using a multiple regression.
ARTICLE | doi:10.20944/preprints201810.0282.v2
Subject: Social Sciences, Economics Keywords: intellectual capital; sustainability; harness; bio-economy; global crisis
Online: 3 January 2019 (11:08:57 CET)
Bio-economy is a major area of the strategy that must enable the European Union to achieve growth: smart, through the development of knowledge and innovation; and sustainable, based on a greener, more efficient economy in resource management. We believe that the progress of bio-economy cannot be achieved without the harnessing of intellectual capital. Our research aimed to emphasize the benefits of the dynamics of the intellectual capital growth on the evolution of the bio-economy. The aim of this analysis was to study the established link between the Energy Intensity of the Economy (EIE) and a number of factors that can measure the intellectual capital, such as: Market Capitalization of Bitcoin, Patent applications listed by European Patent Office and the Turnover from Innovation as a proportion of the total Turnover. The ultimate goal was represented by the generation of a regression model to see what factor influences mostly the progress of the bio-economy at European and Romanian level.
ARTICLE | doi:10.20944/preprints201807.0167.v1
Subject: Engineering, Other Keywords: Bio-separation, magnetic separation, magnetic particles, continuous-flow
Online: 10 July 2018 (10:53:45 CEST)
Bio-separation of natural molecules as well as clinical compounds has been constantly developed in last decades. Several techniques are available but the majority of them presents drawbacks such us impossibility to be applied for industrial purposes. The main limitations for the scaling up are high costs and the fact that the devices work with microfluid dynamics. Nevertheless, magnetic bio-separation is considered the most prone to be used for large scale applications. Herein, we propose a simple magnetic separation method that is not based on microfluid dynamics, can work in a continuous- and high-flow rate and can be easily automated in order to be used for standard separation purposes. It is based on the use of an anisotropic flexible ferric magnetic strip, Teflon hoses and a pumping device. We show the modelling of the separation process along with an experimental test on iron oxide magnetic particles. The results showed that it is possible to remove, and separately collect, more than 92% of magnetic particles from a liquid solution of 100 ml in roughly 15 minutes.
ARTICLE | doi:10.20944/preprints201806.0043.v1
Subject: Earth Sciences, Atmospheric Science Keywords: saccharides; biomass burning; haze; source apportionment; bio-aerosol
Online: 4 June 2018 (12:47:58 CEST)
The characteristics of biogenic aerosols in urban area were explored by determining the composition, temporal distribution of saccharides in PM2.5 in Shanghai. The total saccharides showed a wide range of 15.2 ng/m3 to 1752.8 ng/m3, with the averaged concentrations were 169.8 ng/m3，300.5 ng/m3，288.4 ng/m3，688 ng/m3 in spring, summer, autumn, and winter, respectively. The concerned saccharides include anhydrosaccharides (levoglucosan and mannosan), which were higher in cold seasons due to the increased biomass burning, saccharide alcohols (mannitol, arabitol, sorbitol) and monosaccharides (fructose, glucose), which showed more abundant in warm seasons attributed to the biological emissions. By PMF analysis, four emission sources of saccharides were demonstrated, including biomass burning, fungal spores, soil suspension and plant pollens. Resolution of backward trajectory and fire points showed a process of high concentrations of levoglucosan. We found that concentrations of anhydrosaccharides showed relatively stable under different pollution levels while saccharide alcohols exhibited an obvious decrease, indicated that biomass burning was not the core reason of the heavy haze pollution, however, and high level PM2.5 pollution might inhibit effects of biological activities.
ARTICLE | doi:10.20944/preprints202012.0497.v1
Subject: Materials Science, Biomaterials Keywords: food thickener; flow behavior; tapioca starch; hydroxypropyl distarch phosphate; xanthan gum; dysphagia
Online: 21 December 2020 (10:39:06 CET)
The flow behavior of the administrated fluid matrices demands careful assessments for stability as consumed by individuals with dysphagia. In the present study, we incorporate tapioca starch (TS), hydroxypropyl distarch phosphate (HDP), and xanthan gum (XG) as thickeners into different nectars (300±20 mPa.s) undergoing thermal processing and evaluated their stability. The thickened nectars presented better water holding and oil binding capacities at 25 ℃ than 4 ℃, and the nectars with TS provided the best results for both capacities as well as the highest solubility index and swelling power (p<0.05). All prepared nectars appeared to be shear-thinning fluids with yield stress closely fitting the power law and Casson models. XG-contained nectars presented a higher yield stress and consistency index. Matrices thickened by HDP exhibited a higher viscoelastic property compared to those thickened by TS during thermal processing. TS nectars presented viscous behavior, whereas HDP and XG nectars presented elastic behavior at 80 ℃ processing. The 3-min thermal processing HDP-nectars remained stable and met dysphagia-friendly requirements under 4 ℃ storage for 28 days regardless of the types of fluid bases (distilled water, sport drink, or orange juice). The employed thickeners present adequate physicochemical properties to be potentially utilized for producing dysphagia-friendly formulations.
ARTICLE | doi:10.20944/preprints201908.0235.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: endophytic bacteria; indole-3-acetic acid; cadmium accumulation; phosphate solubilization; reduced glutathione
Online: 23 August 2019 (04:06:54 CEST)
Cadmium (Cd) is a heavy metal that suppresses plant growth; however, application of endophytic bacteria can increase resistance of plants against Cd, as well as improve plant growth. Two bacterial endophytic strains were isolated from Solanum nigrum and were identified as Serratia sp. AI001 and Enterobacter sp. AI002 by 16S DNA sequencing. Strains AI001 and AI002, tolerated up to 25 mg/mL Cd in broth culture and showed phosphate solubilization potential in Pikovskaya agar medium. AI001 and AI002 produced indole-3-acetic acid, which was confirmed by gas spectrometry-mass chromatography. Brassica plants stressed with 0, 5, 15, and 25 mg/L Cd showed significant decrease in plant growth, chlorophyll content and biomass, and significant increase in Cd dose-dependent electrolyte leakage. Inoculation of strain AI001 or AI002 significantly enhanced the plant growth attributes of shoot length, root length, chlorophyll content, and biomass as compared to those in uninoculated plants. Reduced glutathione contents in plants stressed with different concentrations of Cd also increased with inoculation of AI001 and AI002. The reason of Cd resistance enhancement in plants by inocula could be due to their greater plant growth promoting activities as well as their antioxidative response.
REVIEW | doi:10.20944/preprints202301.0203.v1
Subject: Chemistry, Analytical Chemistry Keywords: pyrolysis; pyrolysis reactors; bio-waste; biofuels; biochar; pyrolytic gas
Online: 12 January 2023 (02:11:03 CET)
Pyrolysis has been applied in the human economy for many years, and it has become a significant alternative to the production of chemical compounds, including biofuels. The article focuses mostly on recent achievements in the technical and processing aspects of pyrolysis. This review provides an overview of the recent advanced pyrolysis technology used in gas, bio-oil, and biochar production. The key parameters to maximize the production of specific chemical compounds were discussed and considered during the construction of the reactors. The emphasis is put on optimizing the process parameters, technical requirements, and renewable energy use in the process and conception to improve the efficiency of product production. The application of pyrolysis gas, oil, and biochar as valuable chemical compounds are related to the intensifying effects of climate change, biofuel production, and waste management in accordance with the principles of sustainable development.
ARTICLE | doi:10.20944/preprints202012.0230.v2
Subject: Behavioral Sciences, Social Psychology Keywords: plastic; bio-based plastic; willingness to pay; attitudes; recycling
Online: 24 March 2021 (16:54:11 CET)
Fossil-based plastics are significant contributors to global warming through CO2 emissions. For more sustainable alternatives to be successful, it is important to ensure that consumers become aware of the benefits of innovations such as bio-based plastics, in order to create demand and a willingness to initially pay more. Given that consumer attitudes and (inaccurate) beliefs can influence the uptake such new technologies, we investigated participants’ attitudes towards fossil-based and bio-based plastic, their perceived importance of recycling both types of plastic, their willingness to pay, and their perceptions of bio-based plastic in four studies (total N = 961). The pre-registered fourth study experimentally manipulated information about bio-based plastic and measured willingness to pay for different types of plastic. The results suggest participants hold very favourable attitudes and are willing to pay more for bio-based products. However, they also harbour misconceptions, especially overestimating bio-based plastic’s biodegradability, and they find it less important to recycle bio-based than fossil-based plastic. Study 4 provided evidence that educating consumers about the properties of bio-based plastic can dispel misconceptions, retain a favourable attitude and a high willingness to pay. We found mixed evidence for the effect of attitudes on willingness to pay, suggesting other psychological factors may also play a role. We discuss how attitudes and misconceptions affect the uptake of new sustainable technologies such as bio-based plastics and consumers’ willingness to purchase them.
ARTICLE | doi:10.20944/preprints202008.0486.v1
Subject: Life Sciences, Microbiology Keywords: Bacillus subtilis; Bio-surfactants; emulsification index; Hydrocarbons; surface tension.
Online: 21 August 2020 (13:27:24 CEST)
Bio-surfactants are surface-active molecules which are produced by the wide range of microbes including bacteria, fungi, and yeast. This study was conducted to identify bio-surfactants by Bacillus subtilis combined with use of cheap substrates and industrial wastes (Mustard cake, Whey and Soya cake) which are found locally in Nepal. Bacillus subtilis, one of the most potential bio-surfactants producer; was isolated from soil sample of hydrocarbon contaminated site. Isolates were grown in a Minimal Salt Media (MSM) with 10% (v/v) mustard oil cake, whey and soya cake separately. The presence and potential of surfactant was determined by the oil spreading technique, emulsification index (%E24) and surface tension measurement. It was revealed that the surface tensions of cell free extract were 54.41, 60.02 and 56.64 mN/m for from mustard cake, whey and soya cake respectively as compared to distilled water (72.09) at 25oC. The emulsification index values are was found to be highest in engine oil from the bio-surfactant extracted from mustard cake, soya cake and whey respectively. Similarly, mustard oil showed the lowest value of emulsification index. The highest emulsification activity was shown in mustard oil i.e. 1.13 from the cell free extract from mustard oil and lowest in engine oil i.e., 0.07, by the extract from soya cake medium, when measured in spectrophotometer at 540 nm. In conclusion, strain of Bacillus subtilis was found to be the potential surface active agent producers on the mustard oil cake, which can be useful medium for various environmental, food and industrial processes.
COMMUNICATION | doi:10.20944/preprints201811.0380.v1
Subject: Engineering, Energy & Fuel Technology Keywords: bio-oil; biomass conversion; carbide catalyst; ketonization; doped carbides
Online: 16 November 2018 (07:10:50 CET)
Carboxylic acids such as acetic acid and propionic acid have been investigated as representative components for fast pyrolysis (FP) bio-oil upgrading. Selective catalytic conversion of carboxylic acids can enhance bio-refinery processing economics through catalyst preservation and process intensification. Various metal-doped molybdenum carbide bead catalysts have been synthesized and developed in this work. Our aim is to enable selective conversion of carboxylic acids. In the case of acetic acid conversion, calcium doped Mo2C beads offer the highest yield of acetone ~96% at 450 °C among undoped and Ca or Ni doped catalysts. By comparing hot gas filter with and without Ca-Mo2C catalyst tested with real FP vapors, the former showed a 36.7% reduction of acetic acid, a 37.5% reduction of small ketones in aqueous phase, and a ~50% reduction of methoxies (methoxy phenols and methoxy aromatics) in organic phase. The conversion resulted in the formation of more long chain chemicals in the organic phase, which are more amendable for downstream upgrading.
ARTICLE | doi:10.20944/preprints201811.0351.v1
Subject: Materials Science, Polymers & Plastics Keywords: blend; bio-derived polymers; compatibilization; thermoplastic matrix for composite
Online: 15 November 2018 (08:49:26 CET)
High density polyethylene (HDPE) and poly(lactic) acid (PLA) blends with different ratios of both polymers, namely 30:70, 50:50 and 70:30, were produced. Polyethylene grafted maleic anhydride and a random copolymer of ethylene and glycidyl methacrylate, were also proposed as compatibilizers to modify HDPE-PLA optimal blends and were added in the amounts of 1, 3 and 5 wt.%. Blends properties have been evaluated through different aspects by performing tensile tests, scanning electron microscopy to analyze blend morphology and interfaces, and thermomechanical analysis through differential scanning calorimetry, thermo-gravimetric analyses and infrared spectroscopy. The second blend, the one with equal amounts of HDPE and PLA seems to represent a good balance between high amount of bio-derived charge and acceptable mechanical properties. This suggests a good potential of these blends, which would be a good starting point for the production of composites with lingo-cellulosic fillers.
ARTICLE | doi:10.20944/preprints201811.0318.v1
Subject: Engineering, Other Keywords: Sewage sludge, P bio-availability, P species, SMT protocol
Online: 13 November 2018 (15:07:58 CET)
The species and bio-availability of phosphorus (P) in primary, secondary and digested sludge were fractionated and further analyzed in this study. Results showed that inorganic P (IP) was the primary P fraction in the secondary sludge and digested sludge, in which non-apatite IP (NAIP) amounted to 91.6% and 69.3% of IP, respectively. Organic P (OP), accounting for about 71.7% of total P (TP), was the dominant P composition in primary sludge. The content of bio-available P was about 9.7, 43.4, 29.8 mg-P/g-TS in primary sludge, secondary sludge and digested sludge, respectively, suggesting secondary sludge is the optimal choice when land application of sewage sludge is taken into consideration, followed by digested sludge and primary sludge. Polyphosphate and orthophosphate, comprising approximately 54.3% and 89.2% of TP, was the dominant P species in the secondary sludge and digested sludge, respectively. Monoester-P (54.6% of TP in extract) and diester- P (24.1%) were identified as OP species in primary sludge by Phosphorus-31 nuclear magnetic resonance (31PNMR). The present results would be helpful for P recovery and recycle from sewage sludge in wastewater treatment plant.
ARTICLE | doi:10.20944/preprints201809.0421.v1
Subject: Materials Science, Nanotechnology Keywords: Nanoparticles – Bio-nano interfaces – Electrostatic interactions – Supported Lipid Bilayers
Online: 20 September 2018 (16:29:35 CEST)
The impact of nanomaterials on lung fluids or on the plasma membrane of living cells has prompted researchers to examine the interactions between nanoparticles and lipid vesicles. Recent studies have shown that nanoparticle-lipid interaction leads to a broad range of structures including supported lipid bilayers (SLB), particles adsorbed at the surface or internalized inside vesicles, and mixed aggregates. Today, there is a need to have simple protocols that can readily assess the nature of structures obtained from particles and vesicles. Here we apply the method of continuous variation for measuring Job scattering plots and provide analytical expressions for the scattering intensity in various scenarios. The result that emerges from the comparison between modeling and experimental measurements is that electrostatics plays a key role in the association, but it is not sufficient to induce the formation of supported lipid bilayers.
ARTICLE | doi:10.20944/preprints201805.0361.v1
Subject: Engineering, Energy & Fuel Technology Keywords: bio-digesters; household income levels; renewable energy; socio-economic
Online: 25 May 2018 (10:55:58 CEST)
1) Background: The environmental, financial and social questions in Africa remain unanswered up-to-date, with the rapid increase in human population and the demand for fuel energy, trigger the need to generate data on the socio-economic factors influencing the knowledge of use and adoption of family-sized bio-digesters. The increasing prices of fossil fuels and taxes on energy sources require finding the alternative, clean and economical sources of energy for households in developing countries. Moreover, in Africa, the consumption of firewood and charcoal continues to increase, with wood fuel consumption predicted to increase by 2030 to over 140%. The study objectives were 1) to determine the socio-economic characteristics of the people in Ngoma district, 2) to assess socio-economic factors influencing people to use and adopt family-sized bio-digesters. 2) Methods: Quantitative data collected with semi-structured questionnaires and interviews were analyzed using descriptive statistics. 3) Results: The results show that many households had not realized the potential benefits of biogas use and adoption in Rwanda. The study further found that a number of factors such as household income levels, socio-economic, technological, and institutional influence the household use and adoption of biogas energy. 4) Conclusions: At the end, the study suggests the need for all players such as Government, Non-Governmental Organizations (NGO's) and local communities to work together to provide incentives and favorable environment that can attract individual households to invest in biogas energy production and utilization.
ARTICLE | doi:10.20944/preprints202104.0730.v1
Subject: Earth Sciences, Atmospheric Science Keywords: Prospective analysis; strategic actors; scenarios; objectives; policies; phosphate extraction; mining project; rural communities
Online: 28 April 2021 (07:47:34 CEST)
Followed by the aspect of respect for rights 20, the social and environmental issue has a score of 19.9, the dialogue issue is 19. In short, the proximity plan indicates that the policies used regarding the issue of generating employment and economic growth (Empresa Mantaro Perú SAC), continue to be the strategic variables in the first instance, but they are far from the social actors (rural communities of Aco, Vico, Cruz Pampa and others) and environmental (Junín environmental dialogue table) and Ombudsman's Office (rights) that are currently closer together. The actor from the Archbishop of Huancayo referred to communication is one of the driving variables of power. The proximity plan shows us that the policies used regarding the issue of generating employment and economic growth (Empresa Mantaro Perú SAC), continue to be the strategic variables in the first instance, but that they are far from the social actors (Rural Communities of Aco , Vico, Cruz Pampa and others) and environmental (Junín Environmental Dialogue Table) and Ombudsman's Office (rights) that are currently closer together. The actor from the Archbishop of Huancayo referred to communication is one of the driving variables of power. The proximity plan shows us that the policies used regarding the issue of generating employment and economic growth (Empresa Mantaro Perú SAC), continue to be the strategic variables in the first instance, but that they are far from the social actors (Rural Communities of Aco , Vico, Cruz Pampa and others) and environmental (Junín Environmental Dialogue Table) and Ombudsman's Office (rights) that are currently closer together. The actor from the Archbishop of Huancayo referred to communication is one of the driving variables of power. but they are far from the social actors (rural communities of Aco, Vico, Cruz Pampa and others) and environmental (Junín Environmental Dialogue Table) and the Ombudsman's Office (rights) that are closer together today. The actor from the Archbishopric of Huancayo referred to communication, is within the driving variables of power. but they are far from the social actors (rural communities of Aco, Vico, Cruz Pampa and others) and environmental (Junín Environmental Dialogue Table) and the Ombudsman's Office (rights) that are currently closer together. The actor of the Archbishopric of Huancayo referred to communication, is within the driving variables of power.
REVIEW | doi:10.20944/preprints201912.0165.v2
Subject: Medicine & Pharmacology, Nutrition Keywords: glucose; pentose phosphate pathway; NADPH; redox balance; glycogen; glycolysis; stress resistance; insulin resistance
Online: 30 January 2020 (12:49:19 CET)
A human organism depends on stable glucose blood levels in order to maintain the metabolic needs. Glucose is considered as the most important energy source and glycolysis is postulated as a backbone pathway. However, when glucose supply is limited, ketone bodies and amino acids can be used to produce enough ATP. In contrast, for the functioning of pentose phosphate pathway (PPP) glucose is essential and cannot be substituted by other metabolites. PPP generates and maintains levels of NADPH needed for reduction of oxidized glutathione and protein thiols, synthesis of lipids and DNA as well as for xenobiotic detoxification, regulatory redox signaling and counteracting infections. Flux of glucose into a PPP, particularly under extreme oxidative and toxic challenges is critical for survival, whereas the glycolytic pathway is primarily activated when glucose is abundant, and there is lack of NADP+ that is required for activation of glucose-6 phosphate dehydrogenase. An important role of glycogen stores in resistance to oxidative challenges is discussed. Current evidences explain disruptive metabolic effects and detrimental health consequences of chronic nutritional carbohydrate overload and provides new insights into positive metabolic effects of intermittent fasting, caloric restriction, exercise, and ketogenic diet through modulation of redox homeostasis.
ARTICLE | doi:10.20944/preprints201907.0194.v1
Subject: Materials Science, Biomaterials Keywords: Cuttlefish bone; Biphasic calcium phosphate; Porous scaffolds; Sol-gel coatings; Bioactivity; Tissue engineering
Online: 16 July 2019 (12:32:14 CEST)
The combination of calcium phosphates (CaP) with bioactive glasses (BG) has received an increased interest in the field of bone tissue engineering. In the present work, biphasic calcium phosphates (BCP) obtained by hydrothermal transformation (HT) of cuttlefish bone (CB) were coated with a Sr-, Mg- and Zn-doped sol-gel derived BG. The scaffolds were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The initial CB structure was maintained after HT and the scaffold functionalization did not jeopardize the internal structure. The results of in vitro bio-mineralization after immersing the BG coated scaffolds in simulated body fluid (SBF) showed extensive formation of bone-like apatite onto the surface of the scaffolds. Overall, the functionalized CB derived BCP scaffolds revealed promising properties for their use in bone tissue engineering field.
ARTICLE | doi:10.20944/preprints201801.0054.v1
Subject: Engineering, Electrical & Electronic Engineering Keywords: hydroponics; interdigitated electrodes; molecularly imprinted polymer; nutrient monitoring; phosphate; polymer sensor; precision agriculture
Online: 8 January 2018 (09:22:17 CET)
An interdigitated electrode sensor was designed and microfabricated for measuring the changes in the capacitance of three phosphate selective molecularly imprinted polymer (MIP) formulations, in order to provide hydroponics users with a portable nutrient sensing tool. The MIPs investigated were synthesised using different combinations of the functional monomers methacrylic acid (MAA) and N-allylthiourea, against the template molecules diphenyl phosphate, triethyl phosphate and trimethyl phosphate. A cross-interference study between phosphate, nitrate and sulfate was carried out for the MIP materials using an inductance, capacitance and resistance (LCR) meter. Capacitance measurements were taken applying an alternating current (AC) with a potential difference of 1 V root mean square (RMS) at a frequency of 1 kHz. The cross-interference study demonstrated a strong binding preference to phosphate over the other nutrient salts tested for each formulation. The size of template molecule and length of the functional monomer side groups also determined that a combination of a short chain functional monomer in combination with a template containing large R-groups produced the optimal binding site conditions when synthesising a phosphate selective MIP.
Subject: Biology, Animal Sciences & Zoology Keywords: CTs molecular weight; ruminal fermentation; bio-hydrogenation; milk compositions; goat
Online: 20 September 2020 (14:44:56 CEST)
The aim of this study was to investigate the effect of condensed tannin (CTs) with differing molecular weight on their capacity to modify the fatty acid profile in milk. Twenty multiparous crossbred lactating dairy goats were assigned in a randomized complete block design (RCBD), and were subjected to receive the dietary treatments as followings; T1: control (with no CTs supplementation), T2: supplemented with mangosteen peel in a concentrate as a source of low molecular weight CTs at level of 3.0 %DM of CTs equivalent, T3: supplemented with the same diet with T2 but added with polyethylene glycol (PEG, as tannin inactivator) as the control of T2, and T4: supplemented with quebracho CT extract (UNITAN ATO, Buenos Aires, Argentina; 75-77 % tannins) in a concentrate as a source of high molecular weight CTs at level of 3.0 %DM of CTs equivalent, and T5) supplemented with the same diet with T4 but added with PEG as the control of T4. No significant change was detected for feed intake and nutrient digestibility indicate that CTs at level of 3.0 %DM of diet did not showed the detrimental effect to feed intake and nutrient digestibility, however, ruminal fermentation parameters and milk yield and milk compositions did not affected by different source of CT inclusion.
ARTICLE | doi:10.20944/preprints202009.0136.v1
Online: 5 September 2020 (09:40:46 CEST)
This research seeks to interpret the component analysis of an innovative bio-asphalt binder using guayule resin in addition to crumb rubber modifier (CRM) at high concentrations. Such asphalt modification aims to minimize the dependency on virgin asphalt binder and provide new solutions concerning sustainable, flexible pavement industry. Guayule resin is a promising bioresource for asphalt binder replacement. By now, it could be considered a no value byproduct extracted during the guayule natural rubber production. CRM is a recycled material derived from scrap tires. The provided interpretation could help in understanding the asphalt-rubber-guayule interaction mechanism. Fourier transform infrared spectroscopy (FTIR), supported by thermo-gravimetric analysis (TGA), was used to investigate the component analyses of guayule resin composition, asphalt guayule interaction, and asphalt rubber guayule interaction, compared to corresponding asphalt rubber interaction. Additionally, the rheological properties at elevated temperatures were provided to link the microscale properties with the final product performance. The study clarified the distinct carbon and hydrogen compositional elements of guayule resin. Asphalt and guayule resin have similarities in chemical composition and rheological behavior with temperature susceptibility. The asphalt guayule binder had physical interaction. However, when both interacted with rubber, a chemical interaction was attributed, with no difference in rubber dissolution tendency, in asphalt rubber guayule, compared to asphalt rubber. A bio-binder composed of 62.5% asphalt, 25% guayule and 12.5% CRM had the potential to provide rheological properties better than base asphalt. Such behavior was interpreted by a high release of rubber components.
ARTICLE | doi:10.20944/preprints202001.0373.v1
Subject: Chemistry, Analytical Chemistry Keywords: carbon nanostructures; nanodiamonds; metal nanoparticles; functionalization electrochemical (bio)sensor; nanocomposites
Online: 31 January 2020 (02:13:31 CET)
The incorporation of nanomaterials on (bio)sensors based on composite materials has led to important advances in analytical chemistry field due to the extraordinary properties that these materials offer. Nanodiamonds (NDs) are a novel type of material that has raised much attention, as they have the possibility of being produced on large scale by using relatively inexpensive synthetic methodologies. Moreover, NDs present some other interesting features as suitability for fluorescence due to surface functionalization and a proved biocompatibility, which makes them well suited for biomedical applications. In addition, NDs can be modified with metallic nanoparticles (NP), such as silver or gold, in order to combine the special features of both. The aim of this research work is the nanostructuration of novel sensing devices using NDs combined with silver (Ag@NDs) and gold (Au@NDs) nanoparticles. A complete morphological and electrochemical characterization as function of the prepared nanocomposite composition have been performed in order to improve the electroanalytical properties of the developed (bio)sensors.
ARTICLE | doi:10.20944/preprints202001.0140.v1
Subject: Biology, Ecology Keywords: shallot; cabbage; green peach aphid; lacewing; bio-stress; companion planting
Online: 13 January 2020 (15:47:15 CET)
Phloem-feeding insects strive to offset the disadvantageous effects of stressors to sustain their offspring and survive. Adaptive responses to environmental stress are not well understood under complex influences of companion planting, natural enemies, and host gradient. In this study, under predation by lacewing Chrysoperla carnea Stephens (Neuroptera: Chrysopidae), we survey the responses of green peach aphid Myzus persicae Sulzer (Hemiptera: Aphididae), reared on different densities of cabbage Brassica oleracea L. (Brassicales: Brassicaceae) to its shallot companion Allium cepa (L.) var. aggregatum G. Don (Asparagales: Amaryllidaceae). Firstly, aphid aggregative abundance was strongly influenced by shallot perturbation, predator presence and changes in cabbage-host biomass, altering aphid phenotypic plasticity. Interestingly, the shallot and predation negative impacts can be of similar magnitudes. Secondly, changes in the cabbage-host availability and biomass, especially under predation, had a strong impact on aphid traits. Our study underscores the benefits of including shallots as crop-companions in augmenting pest control, but also suggests that the outcome of coupling companion planting with natural enemies is context-dependent and thus should be empirically applied. At the confluence of ecology and agronomy, this work provides insights on how manipulated functional biodiversity may function as an alternative strategy for pestilent herbivory management in model and green-house systems.
ARTICLE | doi:10.20944/preprints201911.0080.v1
Subject: Chemistry, Organic Chemistry Keywords: algal oil; green chemistry; green solvents; extraction; biofuel; bio compound
Online: 8 November 2019 (03:16:06 CET)
The procedures for the extraction and separation of lipids and nutraceutics from microalgae using classic solvents have been used many times. However, these production methods usually require expensive and toxic solvents. Based on our studies involving the use of eco-sustainable methodologies and alternative solvents, we select ethanol (EtOH) and cyclopentyl methyl ether (CPME) for extracting bio-oil and lipids from algae. Different percentage of EtOH in CPME favors the production of an oil rich of SFA useful to production biofuel or rich of compounds bioactive. The proposed method for obtain a rich extract of saturated or unsaturated fatty acids from dry algal biomass is disclosed is eco-friendly and allows a good extraction yield. The method is compared both in extracted oil percentage yield and in extracted fatty acids selectivity to extraction by supercritical carbon dioxide.
ARTICLE | doi:10.20944/preprints201901.0132.v1
Subject: Biology, Other Keywords: Bacteriophages; Bio-control; E. coli O157:H7; Podoviridae; TEM, safety
Online: 14 January 2019 (11:18:57 CET)
Bacteriophages can provide alternative measures for the control of E. coli O157:H7 that is currently an emerging food-borne pathogen of severe public health concern. This study was aimed at characterising E. coli O157:H7 specific phages as potential biocontrol agents for these pathogens. Fifteen phages were isolated and screened against 69 environmental E. coli O157:H7. Only 3 phages displayed broad lytic spectra against environmental shiga toxin-producing E. coli O157:H7 strains. These 3 lytic phages were designated V3, V7 and V8. Subsequent characterization indicated that they displayed very high degree of similarities despite isolation from different locations. Transmission Electron microscopy (TEM) of the phages revealed that they all had isometric heads of about 73 – 77 nm in diameter and short tails ranging from 20 - 25 nm in diameter. Phages V3, V7 and V8 were assigned to the family Podoviridae based on their morphology. Pulsed field gel electrophoresis (PFGE) genome estimation of the 3 phages demonstrated identical genome sizes of ~ 69 nm. The latent periods of these phages were 20 min, 15 min, and 20 min for V3, V7 and V8 respectively while the burst sizes were 374, 349 and 419 PFU/ infected cell respectively. While all the phages were relatively stable over a wide range of salinity, temperatures and pH values, their range of infectivity or lytic profile was rather narrow on environmental E. coli O157:H7 strains isolated from cattle faeces. This study showed that the Podoviridae bacteriophages are the dominant E. coli O57:H7-infecting phages harboured in cattle faeces in the North-West Province of South Africa and due to their favourable characteristics can be exploited in the formulation of phage cocktails for the bio-control of E. coli O157:H7 in meat and other meat products.
ARTICLE | doi:10.20944/preprints201811.0567.v1
Subject: Life Sciences, Biochemistry Keywords: bio-impedance, phase angle, over-hydration, body composition, nutrition, hemodialysis
Online: 23 November 2018 (15:01:18 CET)
Background A body composition monitor (BCM) has a role not only in determining over-hydration (OH) but also as an aid to nutritional assessment. For dialysis patient-specific clinical applications of BCM, it is necessary to clarify the relationship between body composition parameters and OH in healthy Chinese individuals. Methods This cross-sectional study involved 314 healthy individuals with a mean age of 45.7±13.1 years. BCM measurements were performed while the subjects were fasting. Results The mean OH level was 0.379±0.81 L. Lean tissue index (LTI) and Lean tissue mass (LTM) were significantly higher in males (p<0.001), while fat tissue index (FTI) was significantly higher in females (p<0.001). In univariate correlation analysis, FTI, Fat, and ATM had a negative correlation with OH in females and all subjects (p<0.05), while LTM and BCM had a positive correlation in all subjects (p<0.05). There was a significant negative correlation between phase angle (PhA) and OH in males, females, and all subjects (r=-0.634, p<0.001; r=-0.666, p<0.001; r=-0.484, p<0.001, respectively). In multivariate linear regression analysis, PhA (b=-1.266, p<0.001), LTM (b=0.987, p<0.001), age (b=-0.307, p<0.001) were independent predictors of OH. Conclusions This study demonstrated that age, LTM and especially PhA, had important roles in predicting OH in healthy Chinese individuals. In the future, PhA may aid in clinical assessment by helping to titrate dry weight among hemodialysis patients with malnutrition.
ARTICLE | doi:10.20944/preprints201811.0364.v1
Subject: Physical Sciences, Applied Physics Keywords: Bio-sensing, Extinction cross-section, Nano-particles, Plasmons, Raman scattering.
Online: 15 November 2018 (14:54:58 CET)
In this paper, the far field and near field optical responses of a gold nanoparticle are studied and simulated numerically. The electromagnetic field was excited by an electric dipole located near one end of the nanorod, which is used to model the emission of a quantum dot. Another excitation method was also simulated in which an incident plane wave is used. The excitation of dark plasmon modes of the gold nanorod is presented. The Poynting equation was solved numerically to study the influence of the gold nanorod on the dipole radiative power. In addition, the extinction cross section of the gold nanoparticle illuminated by the incident plane wave was calculated to estimate the amount of the scattered and absorbed light.
REVIEW | doi:10.20944/preprints201811.0061.v1
Subject: Chemistry, Other Keywords: reverse micelles, biomimetic, confinement, water dynamics, nanoparticles, nano(bio) sensors
Online: 2 November 2018 (13:25:22 CET)
This paper presents an overview of the principal structural and dynamics characteristics of reverse micelles (RMs) in order to highlight their structural flexibility and versatility, along with the possibility to modulate their parameters in a controlled-manner. The multifunctionality in a large range of different scientific fields is exemplified in two distinct directions: a theoretical model for mimicry of biological microenvironment and practical application in the field of nanotechnology and nano-based sensors. RMs represents a convenient experimental approach that limits the drawbacks of the conventionally biological studies in vitro, while the particular structure confers them the status of simplified mimics of cells by reproducing a complex supramolecular organization in an artificial system. The biological relevance of RMs is discussed in some particular cases referring to the confinement and crowding environment, molecular dynamics of water and cell membrane structure. The use of RMs in different range of applications seems to be more promising due to their structural and compositional flexibility, a high efficiency and selectivity being achieved. The advance in nanotechnology is based on developing new methods of nanomaterials synthesis and deposition. This review highlighting the advantages of using RMs in synthesis of nanoparticles with specific properties and in nano (bio)sensors design.
ARTICLE | doi:10.20944/preprints201809.0552.v1
Subject: Chemistry, Applied Chemistry Keywords: Colliguaya integerrima; Colliguaja salicifolia; vegetable oil; bio-polyol; renewable resources
Online: 28 September 2018 (04:44:48 CEST)
In this study we investigated the potential of two non-edible oil extracts from seeds of Colliguaya Integerrima (CIO) and Colliguaja Salicifolia (CSO) to use as a renewable source for polyols and eventually polyurethane foams or biodiesel. For this purpose, two novel polyols from the aforementioned oils were obtained in a one-single step reaction using a mixture of hydrogen peroxide and acetic acid. The polyol derivatives obtained from the two studied oils were characterized by spectral (FT-IR, 1H NMR and 13C NMR), physico-chemical (e.g. chromatographic analysis, acid value, oxidizability values, iodine value, peroxide value, saponification number, kinematic viscosity, theorical molecular weights, density, hydroxyl number and hydroxyl functionality) and thermal (TGA) analyses according to standard methods. Physico-chemical results revealed that all parameters, with the exception of the iodine value, were higher for bio-polyols (CSP and CIP polyols) compared to the starting oils. The NMR, TGA and FT-IR analyses demonstrated the formation of polyols. Finally, the OH functionality values for CIP and CSP polyols were 4.50 and 5.00, respectively. This result indicated the possible used of CIP and CSP polyols as a raw material for the preparation of polyurethane rigid foams.
REVIEW | doi:10.20944/preprints202212.0231.v1
Subject: Life Sciences, Biotechnology Keywords: methylerythritol phosphate (MEP) pathway; photosynthesis; isoprenoids; lipids; biofuels; gene editing; CRISPR; riboswitch; riboregulators; nanocompartments
Online: 13 December 2022 (07:22:52 CET)
Cyanobacteria are photosynthetic microorganisms capable of using solar energy to convert CO2 and H2O into O2 and energy-rich organic compounds, thus enabling sustainable production of a wide range of bio-products. More and more strains of cyanobacteria are identified that show great promise as cell platforms for the generation of bioproducts. However, strain development is still required to optimize their biosynthesis and increase titers for industrial applications. This review describes the most well-known and newest most promising strains available to the community and gives an overview of current cyanobacterial biotechnology and the latest innovative strategies used for engineering cyanobacteria. We summarize advanced synthetic biology tools for modulating gene expression and their use in metabolic pathway engineering to increase the production of value-added compounds, such as terpenoids, fatty acids, and sugars, to provide a go-to source for scientists starting research in cyanobacterial metabolic engineering.
REVIEW | doi:10.20944/preprints202210.0387.v1
Subject: Chemistry, Applied Chemistry Keywords: bio-stimulant; seaweed liquid extract; rice; Oryza sativa; plant growth promoter
Online: 25 October 2022 (10:55:27 CEST)
Rice is considered as the most important crop for most of the world population. Utilization of seaweed as bio-stimulant can be an alternative way to enhance rice plant growth and productivity, as well as a strategic move to reduce the use of inorganic fertilizer that is harmful to the environment. Seaweed and its derivative products have been widely used as bio-stimulant in the agricultural industry because of their potential use in increasing plant growth and productivity. Auxins, gibberellins, and cytokinin are some of growth regulators found in seaweed extract, as well as macro and micronutrients required for plant growth and development. Several studies have found that seaweed extract has a variety of favorable effects as a plant growth promoter, including early seed germination and establishment, improved nutritional quality, increased yield and crop performance, and increased tolerance to environmental stress. The purpose of this paper is to give a comprehensive overview of the impacts of several seaweed species on seed germination, crop development and production, enhancement of rice plants (Oryza sativa) nutritional quality and the modes of action of seaweed extract includes the chemical components that might be causing plant physiological changes.
Subject: Engineering, Civil Engineering Keywords: Bio-Binder; Guayule Resin; HMA; Mix Performance; Superpave Mix Design; Sustainability
Online: 20 August 2021 (08:54:55 CEST)
Literature revealed the potential of using guayule resin for asphalt cement replacement from the binder’s perspective. However, monitoring guayule resin through binder-aggregate mixture could disclose its performance through field. In this study, designated binders were employed to investigate the applicability of such an innovative replacer through mixture, which were neat asphalt and guayule-based binders (neat guayule, asphalt-rubber-guayule, guayule-rubber binders). Consecutively, field-simulated lab mixtures were prepared to investigate the major distresses. Moisture damage, rutting, fatigue cracking, and thermal cracking resistances were investigated using the modified Lottman (TSR) test, rut test by asphalt pavement analyzer (APA), semi-circular bending (SCB) test, and disk-shaped compact tension (DCT) test, respectively. Additionally, the Hamburg wheel-tracking (HWT) test was employed to evaluate moisture susceptibility and rutting resistance. Outcomes revealed that the neat guayule was susceptible to moisture damage at a 7% air content (Va) when the TSR test was employed. In contrast, all investigated mixtures yielded perfect performances against moisture susceptibility under the HWT test. Guayule-based mixtures perfectly resisted rutting, as analyzed by the rut test and HWT test. Generally, changing parameters (e.g., Va, rubber addition, and partial asphalt replacement by guayule and rubber) enhanced the guayule-based mixture resistance to rutting and moisture damage resulting in acceptable performances. Guayule-based mixture had a high fracture toughness at low temperatures, hence fatigue fracture resistance at intermediate temperatures. Neat guayule mixture with or without rubber addition did not entirely resist thermal fracture. However, partial asphalt replacement by guayule and rubber resisted the thermal fracture to a great extent.
REVIEW | doi:10.20944/preprints202103.0720.v1
Subject: Engineering, Automotive Engineering Keywords: microneedle; microneedle array, interstitial fluid; bio sensing, wearable system; ISF sampling
Online: 30 March 2021 (09:55:02 CEST)
Dermal interstitial fluid (ISF) is a novel source of biomarkers that can be considered as an alternative to blood sampling for disease diagnosis and treatment. Nevertheless, in vivo extraction and analysis of ISF are challenging. On the other hand, microneedle (MN) technology can address most of the challenges associated with dermal ISF extraction and is well-suited for long-term, continuous ISF monitoring as well as in situ detection. In this review, we first briefly summarise the different dermal ISF collection methods and compare them with MN methods. Next, we elaborate on the design considerations and biocompatibility of MNs. Subsequently, the fabrication technologies of various MNs used for dermal ISF extraction, including solid MNs, hollow MNs, porous MNs and hydrogel MNs, are thoroughly explained. In addition, different sensing mechanisms of ISF detection will be discussed in detail. Subsequently, we identify the challenges and propose the possible solutions associated with ISF extraction. A detailed investigation is provided for the transport and sampling mechanism of ISF in vivo. Also, the current in vitro skin model integrated with the MN arrays will be discussed. Finally, future directions to develop a point-of-care (POC) device to sample ISF are proposed.
ARTICLE | doi:10.20944/preprints202103.0618.v1
Subject: Life Sciences, Biochemistry Keywords: Binding sites; Optimization; cell free bacteria condition for metal bio-sorbents
Online: 25 March 2021 (13:59:50 CET)
Bacteria a Microscopic organisms are the most inexhaustible and flexible of microorganisms and constitute a huge division of the whole living earthly biomass, certain microorganisms were found to amass metallic components at a high limit Was Known as Bacterial Bio-sorption Due to their little size, capacity to become under controlled conditions, and their Accommodation to an extensive variety of ecological situations; Potent metal bio-sorbents among microorganisms, at low pH esteems, cell divider ligands are protonated and contend essentially with metals for official. With expanding pH, more ligands, such as amino and carboxyl groups, could be exposed, leading to attraction between these negative charges and the metals, and consequently increment bio-sorption onto the cell surface. Starting with Isolation and identification of heavy metal-resistant bacteria from rock Ore. Studying Factors Affecting Uranium Bio-sorption, Optimization of bacterial growth conditions and optimum for metal uptake by free and immobilized bacterial cells and Desorption ratio of uranium ions adsorbed by Coli. /alginate, All this evidence suggest that functions groups Represented in our study are responsible for metal uptake in our bacterial biomass beside change in peaks position which assigned for it's groups confirm bio-sorption of metal ions from waste due to ions charge interaction comparing with immobilized we found increase in no of binding sites indicate that immobilized bacterial have high efficiency for metal up take which also change in peaks position which assigned for its groups confirm bio-sorption of metal ions from waste due to ions charge interaction, Where the high bio-sorption yield obtained by bacteria, the Uranium & heavy metal bioremediation process expects microorganisms to be joined to a strong surface.
REVIEW | doi:10.20944/preprints202101.0238.v1
Subject: Biology, Anatomy & Morphology Keywords: Artificial reefs; design; building material; bio-monitoring; species diversity; European Atlantic
Online: 13 January 2021 (10:31:56 CET)
Artificial reefs have been deployed in multiple regions of the world for different purposes including habitat restoration and protection, biodiversity and fish stock enhancement, fisheries management and recreation. Artificial reefs can be a valuable tool for ecosystem protection and rehabilitation, helping mitigate the effects of anthropogenic impacts that we face today. However, knowledge on artificial reefs is unevenly distributed worldwide, with some regions having much more quality information available and published (e.g. European Mediterranean Sea area), while others, for instance the North-East Atlantic area, do not. Here, we provide a characterization of purposely built artificial reefs in North-East Atlantic area based on all available literature (i.e. research papers and reports), highlighting the needs and gaps that are vital for establishing future perspectives for artificial reef deployment and research. In the North-East Atlantic area, sixty-one purposely built artificial reefs have been deployed since 1970, mostly between the years 1990-2009, with Spain being the country with the highest number of artificial reefs. The most reported purpose for their deployment is fisheries productivity and habitat/species protection, although, most artificial reefs are multipurpose in order to maximise the benefits of a given financial investment. The majority of artificial reefs were submerged at < 50 m, mainly between 10-20 m of depth. The most used designs were cubic blocks and complex designs made by an array of combined shapes, which mostly consist of concrete (79%). From all the analysed data on artificial reefs, 67% of the cases reported surveys to assess biodiversity after the deployment. However, in 26% of those cases, data was not available. When data was available, only 31% of cases reported long-term biomonitoring surveys (3 years or more). Based upon these findings, we noticed a general lack of scientifically robust data, including records of species and abundance of both fish and invertebrates, as well as macroalgae. Preventing an adequate determination of the best balance between shape, construction material and bio-colonization. Critiques and suggestions are discussed in the light of current available data in order to perform more efficient research, evaluation and functioning of future artificial reefs.
ARTICLE | doi:10.20944/preprints202009.0695.v1
Subject: Social Sciences, Other Keywords: clay minerals; limestone; biochar; trace elements; bio-availability; alkaline degraded soils
Online: 28 September 2020 (17:52:02 CEST)
Ca-bentonite (CB) alone and in a mixture with limestone (L), tobacco biochar (TB) and zeolite (Z) on the fixation, geochemical fractions and absorption of Cd and Zn by Chinese cabbage in smelter heavily polluted (S-HP) and smelter low polluted (S-LP) soils were investigated. The results showed that the CB+TB and CB+L+TB treatments significantly immobilized Cd up to 22.03% and 29.68%, respectively, and reduced uptake by Chinese cabbage shoot to 35.98% with CB+Z+L and 61.35% with CB+L in S-HP and S-LP soils compared with the control. The CB+ Z+ L+TB treatment mobilized Cd up to 4.45% and increased absorption in the shoot by 9.85% in S-HP soil. The greatest immobilization of Zn was 53.18% and 58.20% with the CB+Z+L+TB treatment, which reduced Zn uptake in the plant shoot by 9.94% with CB + L and 58.04 with CB+Z+L+TB in S-HP and S-LP soils. The CB+Z+TB and CB+TB treatments mobilized Zn up to 35.40% and 4.80%, respectively, in both soils. Furthermore, the uptake of Zn in plant shoot was observed by 58.96% and 7.82% with application of CB+Z and CB+TB treatments, respectively, in S-HP and S-LP soils. Overall, our results suggest that Ca-bentonite alone and in mixtures with different amendments can be used to reduce the phyto-extraction of Cd and Zn in Zn-smelter polluted soils.
ARTICLE | doi:10.20944/preprints202002.0306.v1
Subject: Life Sciences, Microbiology Keywords: Egyptian mongoose; Gut microbiota; Microbial profiling; Bio-ecology; Mediterranean Wild Carnivores
Online: 21 February 2020 (08:02:59 CET)
Egyptian mongoose (Herpestes ichneumon) is a medium-size carnivore that in Europe is restricted to Iberia. The bio-ecology of this species remains to be elucidated in several dimensions, including gut microbiota that is nowadays recognized as a fundamental component of mammals. In this work, we investigated the gut microbiota of this herpestid by single-molecule real-time sequencing of twenty paired male (n=10) and female (n=10) intestinal samples. This culture-independent approach enabled microbial profiling based on 16S rDNA and investigation of taxonomical and functional features. The core gut microbiome of the adult subpopulation was dominated by Firmicutes, Fusobacteria, Actinobacteria, and Proteobacteria. Eight genera were uniquely found in adults and five in non-adults. When comparing gut bacterial communities across sex, four genera were exclusive of females and six uniquely found in males. Despite these compositional distinctions, alpha- and beta-diversity analyses showed no statistically significant differences across sex or between adult and non-adult specimens. However, males presented a significantly higher abundance of amino acid and citrate cycle metabolic pathways, compared to the significant overrepresentation in females of galactose’ metabolic pathways. Adults showed a significantly higher abundance of cationic antimicrobial peptide resistance pathways, while non-adults bared a significant overrepresentation of two-component systems associated with antibiotic synthesis, flagellin production and chemotaxis control. This study adds new insights into mongoose bio-ecology palette, highlighting taxonomical and functional microbiome dissimilarities across sex and age classes, possibly related to primary production resources and life-history traits that impact on behavior, diet and gut ecosystem.
ARTICLE | doi:10.20944/preprints201804.0185.v1
Subject: Social Sciences, Economics Keywords: bioeconomy; bio-based products; GDP; policy measures; sustainability assessment; sustainable development
Online: 16 April 2018 (04:54:19 CEST)
Developments in technology have enabled envisioning the derivation of materials and products from renewable biomass, as an alternative to finite fossil-based resource consumption. Therefore, bioeconomy is regarded as an opportunity for sustainable economic growth. Countries are formulating strategies in accordance with their goals to attain from bioeconomy. Proper measurement, monitoring and reporting of the outcomes of these strategies is crucial for long-term success. This study aims to critically evaluate the national methods used for the measurement, monitoring and reporting of bioeconomy contribution to the total economy. For this purpose, research and surveys have been conducted on selected countries (Argentina, Germany, Malaysia, the Netherlands, South Africa and the United States). The results reveal that the bioeconomy targets set up in the strategies often reflect country’s priorities and comparative advantages. However, comprehensive approaches to measure and monitor bioeconomy progress are frequently lacking. Most countries only measure the contribution to gross domestic product (GDP), turnover and employment of the sectors included in their bioeconomy definition, which may provide an incomplete picture. In addition, this study identifies the mismatch between the targets and measurement methods, as the environmental and social impacts of bioeconomy are often foreseen, but not measured. It is concluded that existing global efforts towards a sustainable bioeconomy monitoring can be strengthened and leveraged to measure progress towards sustainable goals.
ARTICLE | doi:10.20944/preprints201711.0090.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: drug delivery; dentine; diffusion; bio-active molecules; CFD; μ-LIF; microfluidics
Online: 14 November 2017 (10:15:29 CET)
This work deals with the numerical investigation of the delivery of potential therapeutic agents through dentinal discs (i.e. a cylindrical segment of the dentinal tissue) towards the dentin-pulp junction. The aim is to assess the main key features (i.e. molecular size, initial concentration, consumption rate, disc porosity and thickness) that affect the delivery of therapeutic substances to the dental pulp and consequently to define the necessary quantitative and qualitative issues related to a specific agent before its potential application in clinical practice. The CFD code used for the computational study is validated with relevant experimental data obtained using micro Laser Induced Fluorescence (μ-LIF) a non-intrusive optical measuring technique. As the phenomenon is diffusion dominated and strongly dependent on the molecular size, the time needed for the concentration of released molecules to attain a required value can be controlled by their initial concentration. Finally, a model is proposed which, given the maximum acceptable time for the drug concentration to attain a required value at the pulpal side of the tissue along with the aforementioned key design parameters, is able to estimate the initial concentration to be imposed and vice versa.
ARTICLE | doi:10.20944/preprints202202.0290.v1
Subject: Materials Science, Biomaterials Keywords: calcium lactate pentahydrate; monocalcium phosphate monohydrate; mechanical activation; powder; brushite; monetite; calcium pyrophosphate; ceramics; biocompatibility
Online: 23 February 2022 (12:07:43 CET)
Ceramic samples based on b-calcium pyrophosphate b-Ca2P2O7 were prepared using firing at 900, 1000, and 1100 oC from powders of g-calcium pyrophosphate g-Ca2P2O7 with preset molar ratios Ca/P=1; 0,975 and 0,95. To prepare powders of g-calcium pyrophosphate g-Ca2P2O7 with preset molar ratio Ca/P=1; 0,975 and 0,95 powder mixtures based on calcium lactate pentahydrate Ca(C3H5O3)2⋅5H2O and, monocalcium phosphate monohydrate Ca(H2PO4)2⋅H2O were treated in an aqua medium in mechanical activation conditions, dried, disaggregated in acetone, and heat-treated at 600 oC. The phase composition of powder mixtures after treatment if planetary mill in aqua medium included both brushite CaHPO4⋅2H2O or monetite CaHPO4, and starting salts. The phase composition of all powder mixtures after disaggregation in acetone in planetary mill included monetite CaHPO4 and starting salts. After heat treatment at 600 oC according to the XRD data phase composition of all powder mixtures was presented by g-calcium pyrophosphate g-Ca2P2O7. The grain size of ceramics increased both with the growth of firing temperature and with decreasing of molar ratio Ca/P of powder mixtures. Calcium polyphosphate (t melt =960–968 oC) formed from monocalcium phosphate monohydrate Ca(H2PO4)2⋅H2O acted like a liquid phase sintering additive. It was confirmed by tests in vitro, that prepared ceramic materials with preset molar ratio Ca/P=1; 0,975 and 0,95 and phase composition presented by b-calcium pyrophosphate b-Ca2P2O7 according to XRD data were biocompatible and could maintain bone cells proliferation.
Subject: Medicine & Pharmacology, Allergology Keywords: adult spinal deformity; lumbosacral junction; anterior lumbar interbody fusion; bone morphogenetic protein; beta-tricalcium phosphate
Online: 28 December 2020 (12:06:09 CET)
Achievement of solid fusion of the lumbosacral junction (L5-S1 level) is an important factor in adult spinal deformity (ASD) surgery. The purpose of this study is to explore the effectiveness and feasibility of injectable rhBMP-2 (a combination of Eschericia coli-derived rhBMP-2 and hydrogel type β-TCP carrier; NOVOSIS Inject) as a bone substitute for the fusion of lumbosacral junction. 20 patients (average age 69.1 years) diagnosed with ASD with sagittal imbalance who underwent surgical treatment including anterior lumbar interbody fusion (ALIF) in the L5-S1 level were evaluated. Injectable rhBMP-2 was applied in L5-S1 ALIF and followed-up for 1-year. Solid fusion rates and changes of clinical outcomes (Oswestry Disability Index [ODI], Visual Analog Scale [VAS] of back and leg) were measured and analyzed at 6 and 12 months after surgery. All postoperative adverse events were evaluated about the association with injectable rhBMP-2. Fusion rates were 68.4% and 100% at 6 and 12 months after surgery. Compared to baseline, ODI were improved to 45.8% and 63.7%, VAS(back) were improved to 69.2% and 72.8%, and VAS(leg) were improved to 49.2% and 64.8% at 6 and 12 months after surgery (p<0.001, respectively). There were no adverse events associated with injectable rhBMP-2. Thus, injectable rhBMP-2 may be a suitable choice of a bone graft substitute when achieving solid interbody fusion in the lumbosacral junction.
ARTICLE | doi:10.20944/preprints202007.0752.v1
Subject: Materials Science, Biomaterials Keywords: self-etching two bottled dental adhesive; 10-methacryloyloxidecyl dihydrogen phosphate monomer; biocompatibility; shear bond strength
Online: 31 July 2020 (13:56:28 CEST)
Dentin bonding is a key in restorative dentistry. Herein, we developed self-etching two-bottle adhesive system containing 10-methacryloyloxidecyl dihydrogen phosphate monomer (MDP) and the physical, mechanical, and biocompatible properties were evaluated. The characteristics of MDP were analyzed using nuclear magnetic resonance (NMR). The water sorption and solubility, the shear-bond strengths to dentin and enamel, and cytotoxicity tests were performed. The newly blended experimental group showed the lowest thickness and water sorption and solubility values. The shear bond strength to enamel and dentin were comparable to control groups (the three other products) all test groups showed 60% of cell viability. In this study, the properties of the newly synthesized adhesive are comparable with the others. The fundamental goal of this study is to get the MDP patent released, as it is intended for domestic production. For this purpose, this dentin adhesive was developed and compared with the commercial product.
ARTICLE | doi:10.20944/preprints201805.0255.v1
Subject: Chemistry, Other Keywords: magnesium potassium phosphate compound; actinides; rare earth elements; uranium; plutonium; americium; lanthanum; neodymium; immobilization; leaching
Online: 18 May 2018 (06:13:11 CEST)
The problem of effective immobilization of liquid radioactive waste (LRW) is key to the successful development of nuclear energy. The possibility of using magnesium potassium phosphate (MKP) compound for LRW immobilization on the example of nitric acid solutions containing actinides and rare earth elements (REE), including high level waste (HLW) surrogate solution is considered in the research work. Under the study of phase composition and structure of the MKP compounds obtained by the XRD and SEM methods, it was established that the compounds are composed of crystalline phases - analogues of natural phosphate minerals (struvite, metaankoleite). The hydrolytic stability of the compounds was determined according to the semi-dynamic test GOST R 52126-2003. Low leaching rates of radionuclides from the compound are established, including a differential leaching rate of 239Pu and 241Am - 3.5 × 10-7 and 5.3 × 10-7 g/(cm2∙day). As a result of the research work it was concluded that the MKP compound is promising for LRW immobilization and can become an alternative material combining the advantages of easy implementation of the technology like cementation and the high physical and chemical stability corresponding to a glass-like compound.
ARTICLE | doi:10.20944/preprints202112.0360.v1
Subject: Engineering, Civil Engineering Keywords: earthen buildings; 3D printing; bio-composites; aging; mechanical properties; lime carbonation; vulcanization
Online: 22 December 2021 (12:11:21 CET)
This paper is part of a study of earthen mixtures for 3D printing of buildings. To meet the ever-growing environmental needs, the focus of the paper is on a particular type of bio-composite for the stabilization of earthen mixtures – the rice husk-lime bio-composite – and on how to enhance its effect on the long-term mechanical properties of the hardened product. Having assumed that the shredding of the vegetable fiber is precisely one of the possible ways to improve the mechanical properties, we compared the results of uniaxial compression tests performed on cubic specimens made with both shredded and raw vegetable fiber, for three curing periods. The results showed that the hardened earthen mixture is not a brittle material in the strict sense, because it exhibits some peculiar behaviors, anomalous for a brittle material. However, being a “designable” material, its properties can be varied with a certain flexibility to get as close as possible to the desired ones. One of the peculiar properties of the hardened earthen mixture deserves further investigation, rather than corrections. This is the vulcanization that occurs (in a completely natural way) in the long term, thanks to the mineralization of the vegetable fiber by carbonation of the lime.
ARTICLE | doi:10.20944/preprints202109.0325.v1
Subject: Life Sciences, Virology Keywords: Virus diversity; Quercus suber; Castanea sativa; hornbeam decline; hypovirulence; bio-control; Portugal.
Online: 20 September 2021 (10:52:30 CEST)
Cryphonectria is a fungal genus associated with economically significant disease of trees. Herein we characterized a novel double-stranded RNA virus from the fungal species Cryphonectria naterciae, a species unexplored as a virus host. De novo assembly of RNA-seq data and Sanger sequencing of RACE (rapid amplification of cDNA ends) clones gave the complete, non-segmented genome (10,164 bp) of the virus termed Cryphonectria naterciae fusagravirus (CnFGV1) that was phylogenetically placed within the previously proposed viral family Fusagraviridae. Of 31 field-collected strains of C. naterciae, 40% tested CnFGV1-positive. Co-cultivation resulted in within-species transmission of CnFGV1 to virus-free strains of C. naterciae. Comparison of the mycelium phenotype and the growth rate of CnFGV1-infected and virus-free isogenic strains revealed frequent sectoring and growth reduction in C. naterciae. Co-culturing also led to cross-species transmission of CnFGV1 to Cryphonectria carpinicola and Cryphonectria radicalis, but not to Cryphonectria parasitica. The virus-infected C. naterciae and the experimentally infected Cryphonectria spp. readily transmitted CnFGV1 through asexual spores to the next generation. CnFGV1 strongly reduced conidiation and in some cases vegetative growth of C. carpinicola, which is involved in the European hornbeam disease. This study is the first report of a fusagravirus in the family Cryphonectriaceae and lays the groundwork for assessing a hypovirulence effect of CnFGV1 against the hornbeam decline in Europe.
REVIEW | doi:10.20944/preprints202106.0026.v1
Subject: Materials Science, Biomaterials Keywords: bio-inspired structures; bioelastomers; hydrogels; polymer-polymer hybrids; injectable biomaterials; adhesive surfaces
Online: 1 June 2021 (11:18:20 CEST)
Novel bio-inspired materials have gained recently great attention, especially in medical applications. Applying sophisticated design and engineering methods, various polymer-polymer hybrid systems with outstanding performance have been developed in last decades. Hybrid systems composed of bioelastomers and hydrogels are very attractive due to their high biocompatibility and elastic nature for advanced biomaterials used in various medical applications such as drug delivery systems and scaffolds for tissue engineering. Herein, we describe the advances in current state-of-the-art design, properties and applications of polymer-polymer hybrid systems in medical applications. Bio-inspired functionalities, including bioadhesiveness, injectability, antibacterial properties and degradability applicable to advanced drug delivery systems and medical devices will be discussed in a context of future efforts towards development of bioinspired materials.
REVIEW | doi:10.20944/preprints202009.0068.v1
Subject: Keywords: Bio-energy; Artiﬁcial intelligence; Industry 4.0; Biodiesel; Biogas; Renewable energy; Supply Chain
Online: 3 September 2020 (09:32:40 CEST)
Machine learning (ML) is penetrating in all walks of life and is one of the major driving forces behind the fourth industrial revolution, typically known as Industry 4.0. This study reviews the state-of-the-art ML applications in the biofuels’ life cycle stages, i.e., soil, feedstock, production, consumption, and emissions. A keyword search is performed to retrieve relevant articles from the databases of the Web of Science and Google Scholar. ML applications in the soil stage were mostly based on the use of satellite images of land for estimation of biofuels yield or suitability analysis of agricultural land. In the second stage of the life cycle, assessment of rheological properties of the feedstocks and their effect on the quality of biofuels were dominant studies reported in the literature. The production stage included estimation and optimization of quality, quantity, and process conditions. The fuel consumption and emissions stage included analysis of engine performance and estimation of emissions temperature and composition, such as NOx, CO, and CO2. This study identiﬁed the following trends: dominant ML method, the stage of life cycle getting more usage of ML, the type of data used for the development of the ML-based models, and the stage-wise frequently used input and output variables. The ﬁndings of this article are beneﬁcial for academia and industry-related people involved in model development in different stages of biofuel’s life cycle.
REVIEW | doi:10.20944/preprints202009.0033.v1
Subject: Engineering, Energy & Fuel Technology Keywords: Bio-energy; Artificial intelligence; Industry 4.0; Biodiesel; Biogas; Renewable energy; Supply Chain
Online: 2 September 2020 (07:56:48 CEST)
Machine learning (ML) is penetrating in all walks of life and is one of the major driving forces behind the fourth industrial revolution, typically known as Industry 4.0. The purpose of the present study is to review the state-of-the-art ML applications in the biofuels' life cycle stages, i.e., soil, feedstock, production, consumption, and emissions. A keyword search is performed to retrieve relevant articles from the databases of the Web of Science and Google Scholar. ML applications in the soil stage were mostly based on the use of satellite images of land for estimation of biofuels yield or suitability analysis of agricultural land. In the second stage of the life cycle, assessment of rheological properties of the feedstocks and their effect on the quality of biofuels were dominant studies reported in the literature. The production stage included estimation and optimization of quality, quantity, and process conditions. The fuel consumption and emissions stage included analysis of engine performance and estimation of emissions temperature and composition, such as NOx CO, and CO2. This study identified the following trends: dominant ML method, the stage of life cycle getting more usage of ML, the type of data used for the development of the ML-based models, and the stage-wise frequently used input and output variables. The findings of this article are beneficial for academia and industry-related people involved in model development in different stages of biofuel’s life cycle.
ARTICLE | doi:10.20944/preprints202007.0217.v2
Subject: Engineering, Mechanical Engineering Keywords: Bio inspired robot; legged Robot; locomotion; position control; walk gait; wooden robot
Online: 20 July 2020 (04:13:18 CEST)
We present the design and overall development of an eight degrees of freedom (DOF) based Bioinspired Quadruped Robot (BiQR). The robot is designed with a skeleton made of cedar wood. The wooden skeleton is based on exploring the potential of cedar wood to be a choice for legged robots’ design. With a total weight of 1.19 kg, the robot uses eight servo motors that run the position control. Relying on the inverse kinematics, the control design enables the robot to perform the walk gait-based locomotion in a controlled environment. The robot has two main aspects: 1) the initial wooden skeleton development of the robot showing it to be an acceptable choice for robot design, 2) the robot’s applicability as a low-cost legged platform to test the locomotion in a laboratory or a classroom setting.
CONFERENCE PAPER | doi:10.3390/sci2020020
Online: 28 March 2020 (00:00:00 CET)
How did life begin on Earth? And is there life elsewhere in the Cosmos? Challenging questions, indeed. The series of conferences established by NoR CEL in 2013, addresses these very same questions. The basis for this paper is the summary report of oral presentations that were delivered by NoR CEL’s network members during the 2018 Athens conference and, as such, disseminates the latest research which they have put forward. More in depth material can be found by consulting the contributors referenced papers. Overall, the outcome of this conspectus on the conference demonstrates a case for the existence of “probable chemistry” during the prebiotic epoch.
Subject: Engineering, Energy & Fuel Technology Keywords: gas turbine engine; two-spool turboprop engine; pt6a engine; aero-thermal model; matlab-simulink; bio-diesel; start-up transient.
Online: 19 September 2019 (05:36:45 CEST)
Instead of simplified steady-state models, with modern computers, one can solve the complete aero-thermodynamics happening in gas turbine engines. In the present article, we describe a mathematical model and numerical procedure to represent the transient response of a PT6A gas turbine engine operating at off-design conditions. The aero-thermal model consists of a set of algebraic and ordinary differential equations that arise from the application of the mass, linear momentum, angular momentum, and energy balances in each engine's component. The solution code has been developed in Matlab-Simulink using a block-oriented approach. Transient simulations of the PT6A engine start-up have been carried out by changing the original Jet-A1 fuel with biodiesel blends. Time plots of the main thermodynamic variables are shown, especially those regarding the structural integrity of the burner. Numerical results have been validated against reported experimental measurements and GasTurb simulations. The computer model has been capable to predict acceptable fuel blends, such that the real PT6A engine can be substituted to avoid the risk of damaging it.
CONCEPT PAPER | doi:10.20944/preprints201610.0076.v1
Subject: Engineering, Electrical & Electronic Engineering Keywords: bio aerosol; Photo Catalytic Oxidation (PCO); hydroxyl; hydrogen peroxide; SPICE; surface sanitizer
Online: 19 October 2016 (10:02:08 CEST)
In this research paper a novel Ultra Violet Photo Catalyst Oxidation (UVPCO) sensor for air and surface sanitization using Common Source (CS) amplifier is presented. The ultra violet photo catalysis is the process in which the highly reactive radicals like H+, OH-and peroxides ions are produced from air in the presence of the ultra violet radiation and photo catalyst. In this process, the free radicals outbreaks the bio aerosols like bacteria, fungus and volatile organic compounds (VOCs) and destroy them. The proposed system is relies on the fast operation of PCS which operates under sub-threshold conditions and reduced computation time. The properties of common source amplifier like very high voltage gain and input output resistance increased the sensitivity as well as stability of the circuit. The system is more user friendly and the outcomes of simulation are fairly in agreement with the theoretical estimation. Keywords: bio aerosol, Photo Catalytic Oxidation (PCO), hydroxyl, hydrogen peroxide, SPICE, surface sanitizer.
HYPOTHESIS | doi:10.20944/preprints202005.0144.v1
Subject: Medicine & Pharmacology, Other Keywords: COVID-19, SARS-CoV-2, pyridoxal 5'-phosphate, pyridoxine, vitamin B6, immune response, IL-6, TNF, type I interferon, lymphopenia, blood clotting, coagulopathy, cytokine storm, sphingosine-1-phosphate, kynurenine, inflammasome, serine hydroxymethyltransferase 2 (SHMT2), hypertension, angiotensin
Online: 8 May 2020 (12:36:03 CEST)
Although most cases of COVID-19 are paucisymptomatic, severe disease is characterized by immune dysregulation, with a decreased type I interferon response, increased inflammatory indicators, surging IL-6, IL-10 and TNFα suggestive of cytokine storm, progressive lymphopenia, and abnormal blood clotting. Factors determining susceptibility to severe disease are poorly understood, although mortality correlates with increasing age and co-morbidities including diabetes and cardiovascular disease (CVD). Pyridoxal 5'-phosphate (PLP) tends to be insufficient in populations particularly vulnerable to COVID-19, including the elderly, the institutionalized, and people with diabetes and CVD, and PLP becomes further depleted during infection and inflammation. In turn, low PLP results in immune imbalance, as PLP is an essential cofactor in pathways regulating cytokine production, in particular type I interferons and IL-6, and in lymphocyte trafficking and endothelial integrity. Furthermore, normalizing PLP levels attenuates abnormalities in platelet aggregation and clot formation. Finally, PLP insufficiency induces excess secretion of renin and angiotensin, and hypertension. In inflammatory disease, pharmacological doses of PLP decrease circulating TNFα, IL-6 and D-dimer, and animal studies demonstrate that supplemental PLP shortens the duration and severity of viral pneumonia. Severe COVID-19 manifests as an imbalance in the immune response and the clotting system. Pharmacological PLP supplementation may therefore mitigate COVID-19 symptoms by alleviating both the immune suppression underlying viral spread and the pathological hypersecretion of inflammatory cytokines, as well as directly bolstering endothelial integrity and preventing hypercoagulability.
ARTICLE | doi:10.20944/preprints202207.0119.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Agroecology; Bio-economic farm models; Crop Syst; Aqua Crop; Organic farming; sustainable development
Online: 7 July 2022 (09:12:26 CEST)
Nations of the world have seen unprecedented changes in climate variables in recent decades. But it is unclear to what extent climate change has impacted and will impact food systems in some developing regions, and how policymakers can frame an approach to encouraging adaptation and advancing climate-smart agriculture. Many studies attempting to link agroecology to climate change adaptation do so without understanding the potential of Agroecology not only to mitigate climate change – which is the weak response – but to reverse its impact and ‘climate proof’ our food systems. By modeling the near and far future impacts of climate change on crop production, we showed how climate will impact crop production under two crop production systems (agroecology and non-agroecology production systems). The overarching aim is to derive sustainable development strategies and lessons for policymakers and climate researchers - essential components of environment and Agricultural development. Using case studies from Nigeria, we observed that transitioning to agroecology, even at the farm level also transforms farm designs, thereby affecting their overall food and nutrition status. The result showed that the use of agroecology management practices not only reduces the impact of climate change in the near future but will also lead to increased crop yield in the future. The finding suggests that to feed the over 400 million projected population of Nigeria by 2050, the use of agroecological practices will be a better alternative to the conventional farming methods. To advance the use of agroecological farming methods, governments at every level in Nigeria need to mainstream organic agriculture in national government policies. This is important as it will not only address climate change impacts but also hunger and poverty.
ARTICLE | doi:10.20944/preprints202202.0019.v1
Subject: Materials Science, General Materials Science Keywords: sorption; kinetics; peat; cenosphere; oil sorption; Weber-Morris; diffusion model; granules; bio-composite
Online: 1 February 2022 (17:09:59 CET)
Among the various methods for collecting oil spills and oil products, including from the water surface, one of the most effective is the use of sorbents. In this work, three-component bio-based composite granular adsorbents were produced and studied for oil products pollution collection. A bio-based binder made of peat, devulcanised crumb rubber from used tyres, and part fly ash as cenospheres were used for absorbent production. The structure, surface morphology, porosity, mechanical properties, and sorption kinetics of the obtained samples were studied. Composite hydrophobicity and sorption capacity to oil products such as diesel fuel (DF) and motor oil (MO) were determined. The obtained pellets are characterised by a sufficiently pronounced ability to absorb oil products such as DF. As the amount of CR in the granules increases, the diesel absorption capacity increases significantly. The case of 30-70-0 is almost 3 times higher than the granules from homogenised peat. The increase in q is due to two factors: pronounced surface hydrophobicity of the samples (Θ = 152°) and a heterogeneous porous granule structure. The presence of the cenosphere in the biocomposite reduces its surface hydrophobicity while increasing the diesel absorption capacity. Relatively rapid realisation of the maximum saturation by the MO was noted. In common, the designed absorbent shows up to 0.7 g·g-1 sorption capacity for MO and up to 1.55 g·g-1 sorption capacity for diesel. A possible mechanism of DF absorption and the limiting stages of the process approximated for different kinetic models are discussed. The Weber-Morris diffusion model is used to primarily distinguish the limiting effect of external and internal diffusion of adsorbate on the absorption process
REVIEW | doi:10.20944/preprints202110.0060.v3
Subject: Biology, Plant Sciences Keywords: RNAi; dsRNA; silencing; encapsulation; liposomes; virus-like particles; polyplex nanoparticles; bio-clay; regulatory
Online: 13 October 2021 (15:39:34 CEST)
RNAi technology is a versatile, effective, safe, and eco-friendly alternative for crop protection. There is plenty of evidence of its use through host-induced gene silencing (HIGS) and spray-induced gene silencing (SIGS) techniques to control viruses, bacteria, fungi, insects, and nematodes. For SIGS, its most significant challenge is achieving stability and avoiding premature degradation of RNAi in the environment or during its absorption by the target organism. One alternative is encapsulation in liposomes, virus-like particles, polyplex nanoparticles, and bioclay, which can be obtained through the recombinant production of RNAi in vectors, transgenesis, and micro/nanoencapsulation. The materials must be safe, biodegradable, and stable in multiple chemical environments, favoring the controlled release of RNAi. Most of the current research on encapsulated RNAi focuses primarily on oral delivery to control insects by silencing essential genes. The regulation of RNAi technology focuses on risk assessment using different approaches; however, this technology has positive economic, environmental, and human health implications for its use in agriculture. The emergence of alternatives combining RNAi gene silencing with the induction of resistance in crops by elicitation and metabolic control is expected, as well as multiple silencing and biotechnological optimization of its large-scale production.