Miracle-dz/UniFAR-FTUs huggingface dataset:
Necesidades de aminoácidos en estados inflamatorios

Los estados inflamatorios y las enfermedades infecciosas modifican notablemente el metabolismo y la utilización de los alimentos. El alcance y la duración de estos cambios metabólicos varía tanto con el tipo como con la severidad de la enfermedad, y en consecuencia, alteran el crecimiento y retrasan la recuperación. Sin embargo, estas alteraciones tienen muchas similitudes que sugieren un modelo de respuesta común entre los animales y el hombre (Spurlock 1997; Reeds y Jahoor 2001). La pérdida de proteína y el retraso del crecimiento acompañan a la respuesta inflamatoria. En pacientes gravemente enfermos, en tres semanas se pierde más del 20% de la proteína corporal, perteneciente principalmente al músculo esquelético (Plank y Hill 2000). Además, la exposición animal a antígenos ambientales tiene como resultado un nivel bajo de la activación del sistema inmune y una reducción del apetito y de la ganancia de la proteína corporal (Williams et al., 1997). El catabolismo neto de las proteínas del músculo es el resultado tanto de la reducción de la síntesis de proteína como del continuo incremento de la ruptura de proteínas y produce un aumento del flujo de aminoácidos desde el músculo hacia los órganos viscerales (Klasing y Austic 1984a y 1984b; Voisin et al., 1996, Breuillé et al., 1998, Jahoor et al., 1999). Estos aminoácidos son utilizados para suministrar energía y para activar procesos como parte de mecanismos de la defensa del cuerpo. Por lo tanto, los aminoácidos son desviados hacia rutas importantes para la defensa del organismo, mientras que el crecimiento y la reproducción pueden verse gravemente afectados por los episodios inflamatorios.
Shewanella oneidensis MR-1 cell-to-cell signaling and its influences on biogeochemical processes

The goal of this project is to decipher the quorum sensing (cell-to-cell signaling) abilities of Shewanella oneidensis MR-1, a Gram-negative bacterium well known for its ability to use geologic substrates, such as Fe and Mn oxides, for respiratory purposes. Overall our results show that S. oneidensis cannot utilize either an acyl-homoserine lactone (AHL) or AI-2 quorum sensing signal, despite previous work that indicated that it produced an AHL that would enhance it ability to growth in certain anaerobic environments. Using a variety of quorum sensing signal sensors, no evidence could be found that S. oneidensis has a typical AHL signal. An in silco analysis of the genome also produced little evidence that S. oneidensis has the genes to accept or relay an AHL signal. S. oneidensis can produce a luminescence response in the AI-2 reporter strain, Vibrio harveyi MM32. This luminescence response is abolished upon deletion of luxS, the gene responsible for catalyzing AI-2. Deletion of luxS also affected biofilm formation. Within 16 hours of growth in a biofilm flow-through reactor, the luxS mutant had an inhibited ability to initiate biofilm formation. After 48 hours of growth, the mutant’s biofilm had developed similarly to wild-type. The addition of synthetic AI-2 did not restore the mutant’s ability to initiation biofilm formation, which led to the conclusion that AI-2 is not likely used as a quorum sensing signal in S. oneidensis for this phenotype. Because of the involvement of LuxS in the activated methyl cycle (AMC) in other organisms, growth on various sulfur sources was examined. A mutation in luxS produced a reduced ability to growth with methionine as the sole sulfur source. Methionine is a key metabolite used in the AMC to produce a methyl source in the cell and homocysteine. This data suggests that LuxS is important in metabolizing methionine and the AMC in S. oneidensis.
An atomic force microscopy study of the growth of a calcite surface as a function of calcium/total carbonate concentration ratio in solution at constant supersaturation

Calcite growth experiments using atomic force microscopy (AFM) were conducted at two constant values of supersaturation (Ω1 = 5.248 and Ω2 = 6.457) while varying the Ca2+ to CO32− concentration ratio. The calcite growth rate and the morphology of growth depend on the solution stoichiometry. At a constant degree of supersaturation, the growth rate was highest when the cation/total carbonate anion ratio, r*, was equal to 1 but decreased nonsymmetrically for higher or lower values of r*. The observed dependence of growth rates on solution stoichiometry can be explained by nonequivalent attachment frequencies of cation and anion at ratios that differ from 1. At the same time, the morphology of the closing etch pits and of the forming nuclei was different when the rate changed, suggesting a change in the crystal growth mechanism.
Characterizations of photoconductivity of graphene oxide thin films

Characterizations of photoresponse of a graphene oxide (GO) thin film to a near infrared laser light were studied. Results showed the photocurrent in the GO thin film was cathodic, always flowing in an opposite direction to the initial current generated by the preset bias voltage that shows a fundamental discrepancy from the photocurrent in the reduced graphene oxide thin film. Light illumination on the GO thin film thus results in more free electrons that offset the initial current. By examining GO thin films reduced at different temperatures, the critical temperature for reversing the photocurrent from cathodic to anodic was found around 187°C. The dynamic photoresponse for the GO thin film was further characterized through the response time constants within the laser on and off durations, denoted as τon and τoff, respectively. τon for the GO thin film was comparable to the other carbon-based thin films such as carbon nanotubes and graphenes. τoff was, however, much larger than that of the other's. This.
Organochlorine pesticides in surface soils and sediments from obsolete pesticides dumping site near Lahore city, Pakistan: contamination status and their distribution

Surface soil and sediment samples were collected from the surroundings of Lila stream, which passes through the obsolete pesticides dumping area Kalashah Kaku near Lahore city, to evaluate the residual levels of 19 organochlorine pesticides (OCPs), their distribution and potential sources. OCPs followed the order: ∑ DDT>∑ HCH>dicofol>endrin>heptachlor>dieldrin. Ratios of β to γ-HCH highlighted an old source of technical HCH in the study area, whereas the predominance of p, p′-DDT and p, p′-DDE indicated presence of technical DDT in surface soils. Factor analysis based on principal component analysis identified the origin of OCPs from industrial activities in Kalashah Kaku and waste dumping from Ittehad Chemical Industries via open drains into Lila stream. Greater levels of DDTs and HCHs above quality guideline pose potential exposure risk to biological organisms, safety of agricultural products and human health in the surrounding of Lila stream.
Homogeneous Ternary H2SO4-NH3-H2O Nucleation and Diesel Exhaust: a Classical Approach

The classical nucleation theory was used to model ternary nucleation at temperatures and concentrations observed in diluting diesel exhaust. The nucleation rate does not markedly depend on the NH3 concentration below the level of 0.8 ppb, with the binary H2O–H2SO4 mechanism dominating. This rules out the effect of dilution air ammonia levels on nucleation mode formation in most cases. On the other hand, with high NH3 concentration in the case of SCR (Selective Catalytic Reduction) technology, we predict a dependence between the ammonia slip and the nucleation mode concentration.
BTEX Exposures among Automobile Mechanics and Painters and Their Associated Health Risks

ABSTRACT We measured the concentrations of benzene, toluene, ethylbenzene, and xylenes (BTEX) in the ambient air of automobile repair garages in Montreal, Canada, using the direct atmospheric pressure chemical ionization-tandem mass spectrometry (APCI-MS/MS) method. Among all the air samples analyzed, toluene was the most abundant BTEX-species (127–1101 μg/m3) followed by xylenes (50–323 μg/m3), ethylbenzene (11–65 μg/m3), and benzene (9.2–23 μg/m3). BTEX levels where ventilation was controlled simultaneously by both mechanical and natural systems were significantly less than levels at garages where only natural ventilation was used. Results suggest that multiple sources contribute to the occupational exposure of automobile mechanics and painters to the BTEX. Owing to the toxic effects of these chemicals, both chronic non-cancer hazard and integrated lifetime cancer risk due to the exposure of this occupational group were assessed. The levels of the BTEX measured at all the garages were less than the established limits for occupational exposure; still, benzene levels pose a potential cancer risk for the workers. At the prevailing levels of BTEX, they may not cause any chronic non-cancer problems for the workers.
DETERMINATION OF RUTIN IN HYPERICUM PERFORATUM EXTRACT BY CAPILLARY ELECTROPHORESIS

A capillary zone electrophoretic (CZE) method for the determination of rutin in an ethanolic extract of the aerial parts of Hypericum perforatum (Hypericaceae) is described. The analysis was performed using a fused-silica capillary and a background electrolyte consisted of 10% ethanol and 20 mM borate buffer at pH 8.0 applied at a potential of 28 kV, vacuum injection of 1 s and detecting at 200 nm. Rutin had a migration time of 10.1 ± 0.2 min. Reproducibility was 1.26% for 9.37 × 10−5 M standard rutin. Detection limit was 2.7 × 10−6 M (S/N = 3). A well-correlated calibration equation was obtained for the mentioned conditions. The amount of rutin in the total plant material was found to be 0.21% ± 0.02.
Apatite - An Adaptive Framework Structure

Apatite, the most common phosphate mineral, is generally described by the formula Ca5(PO4)3(OH,F,Cl) or, more completely with regard to its usual description in P 63/ m symmetry, by the unit cell content [Ca4][Ca6][(PO4)6][OH,F,Cl]2. An earlier volume of the Reviews series (Kohn et al. 2002) has dealt with the mineralogy and crystallography of apatite sensu stricto (Hughes and Rakovan 2002) and the diverse compounds that adopt apatite or apatite-like structures (Pan and Fleet 2002; Huminicki and Hawthorne 2002). In addition, apatite compilations have appeared at regular intervals (Wychoff 1965; McConnell 1973; Nriagu and Moore 1984; Brown and Constantz 1994; Elliott 1994) as the breadth of apatite chemistry has expanded and the level of understanding of its importance with respect to the mineral, materials, environmental, and biological sciences increased. It is not therefore, the purpose of this chapter to restate these excellent reviews, but rather, to focus on microporosity in apatites, a feature which allows ion conduction and exchange, and that is proving to be an important consideration for fashioning synthetic analogues of these minerals in technologically advantageous ways. The notion of apatite as an industrially significant microporous mineral is not new. In 1944, V. M. Goldschmidt who had studied apatite deposits in Scandinavia and at that time had found refuge from war-ravaged Europe at the Macaulay Institute of Soil Research, Aberdeen (Kauffman 1997; McIntyre 2004) persuaded C. A. Beevers to undertake a new refinement of fluorapatite. The results collected in the seminal paper of Beevers and McIntyre (1946), lead not only to the most accurate crystallographic data available at that time, but also provided the first overview of [Ca4][Ca6][(PO4)6][F] …
A Cobalt(II)‐containing Metal‐Organic Framework Showing Catalytic Activity in Oxidation Reactions

A metal-organic framework (MOF) containing redox active CoII atoms, [CoII(BPB)]·3DMF (1), has been prepared from the solvothermal reaction of CoII nitrate and 1,4-bis(4′-pyrazolyl)benzene (H2-BPB) in dimethylformamide (DMF). Compound 1 constitutes a porous coordination framework that is built up by interconnecting 1D CoII polymer chains with (BPB)2− ligands. The thermal stability of 1 was investigated by thermogravimetric (TG) analysis and variable-temperature X-ray powder diffraction (VTXRPD), which indicate that the framework of 1 is stable upon removal of solvent molecules. The argon adsorption isotherm of 1 at 77 K indicates a porous structure with a BET surface area of 1207 m2/g. As a test reaction for catalytic activity of 1, the oxidation of cyclohexene was examined employing tert-butyl hydroperoxide as oxidant. The maximum substrate conversion achieved after 12 h was 62 % with an estimated turn-over number (TON) of 44 based on the number of converted substrate molecules (cyclohexene) per CoII atom.
Climate Change: The Science, Impacts and Solutions

[1] Stern, N. et al., 2007, The Economics of Climate Change: The Stern Review (Cambridge: Cambridge University Press). [2] Diamond, J., 2005, Collapse: How Societies Choose to Fail or Succeed (New York: Viking Press). [3] Hardin, G. , 1968, The tragedy of the commons. Science, 162, 1243–1248. [4] Hardin, G. , 1974, Lifeboat ethics: the case against helping the poor. Psychology Today, 8, 38–43. [5] Dasgupta, P., 2008, Nature in economics. Environmental Resource Economics, 39(1), 1–7. [6] Helm, D. and Hepburn, C. (eds), 2009, The Economics and Politics of Climate Change (Oxford: Oxford University Press). [7] Lipsey, R. and Lancaster, K. (1956) The general theory of second best. Review of Economic Studies, 24(1), 11–32. [8] Bennear, L.S. and Stavins, R. (2007) Second-best theory and the use of multiple policy instruments. Environmental Resource Economics, 37(1), 111–129.
Influence of biotin lipid surface density and accessibility on avidin binding to the tip of an optical fiber sensor

LB films doped with biotin lipids were deposited at the tip of an evanescent fiber optic (EFO) sensor, and the fluorescence intensity of FITC-labeled avidin bound to the sensor tip was monitored. The influence of receptor density and receptor surface accessibility on avidin binding to, and desorption from, the sensor surface was investigated. This was accomplished by varying the doping density from 0 to 100 mol 9% of two biotinylated phosphatidylethanolamines B-DPPE and B-X-DPPE, where B-X-DPPE is essentially identical to B-DPPE, except B-X-DPPE has a six carbon amino acid spacer interposed between the DPPE and the biotin hapten. In general, increasing the biotin lipid surface density or the biotin hapten accessibility increased both the affinity and amount of avidin bound to the sensor tip. Increasing the biotin lipid doping density also hastened the binding of avidin to a relatively inaccessible B-DPPE hapten, but slowed the binding of avidin to the more accessible B-X-DPPE hapten. Overall, avidin bound to the biotin-doped sensor surface 3-4 orders of magnitude slower and dissociated from the sensor surface considerably faster than that observed for avididbiotin binding and dissociation in solution, particularly at low biotin doping densities. These observations suggest a sterically hindered binding of avidin to the biotin lipids at the sensor surface.
TOXICITY SCREENING OF THERAPEUTIC DRUGS

INTRODUCTION In the course of in vitro systems search for the toxicity screening of therapeutic drugs (TDs), different cellular models have been applied to examine their adverse effects in isolated organs. This article describes a simple method to determine effects of TDs at the cell membrane level. The cell membrane is an assembly of proteins and lipids that separate inside from outside, protecting the cell interior. The membrane is also involved in a variety of indispensable cellular functions. It is responsible for the selective transport of molecules and ions into and out of the cell in the extensive network responsible for the traffic between organelles. Without exception, these activities depend on, and are influenced by the physical milieu provided by the molecules making up the membrane bilayers. Changes in the physical and chemical environment of the cell membranes have a direct effect on the membrane structure with serious effects on the cell functions [1–2]. Most biological membranes possess an asymmetric trans-bilayer distribution of phospholipids [3]. Thus, for instance, most eukaryotic plasma membranes present a high percentage of the phospholipids sphingomyelins and phosphatidylcholines in the outer monolayer, whereas the inner one is generally richer in phosphatidylethanolamines, phosphatidylserines, and phosphatidylinositols. However, the existence of asymmetric plasma membranes is less certain in bacteria than in eukaryotes. Studies of the phospholipid distribution of a grampositive bacteria revealed that the outer monolayer is rich in phosphatidylglycerols, the inner one in phosphatidylinositols, while cardiolipins are symmetrically distributed between both monolayers. Studies on gram-negative bacteria such as Escherichia coli have detected phosphatidylethanolamines in the outer membrane, whereas the cytoplasmic membrane has been reported to be rich in phosphatidylglycerols and cardiolipins.
Estudo da erosão na microbacia do Ceveiro (Piracicaba, SP): I - Estimativa das taxas de perda de solo e estudo de sensibilidade dos fatores do modelo EUPS

Accelerated soil erosion is a serious global problem that degrades agriculture lands. Since erosion research is normally expensive and time-consuming, the use of models allows to estimate soil losses at locations and under conditions not represented directly in the research. The objective of this study was to estimate the soil erosion in an area intensively cultivated with sugarcane near the city of Piracicaba, Sao Paulo, contributing to diagnose the current land uses aimed at controlling erosion. The study was carried out based on a geographic information system using the universal soil loss equation (USLE) to estimate erosion. A specific objective of the study was to analyze the influence of K (soil erodibility), LS (topography), C (crop use and management) and P (erosion control practices) factors in soil loss estimates. The results show an intense soil degradation process by accelerated erosion in nearly two-thirds of the studied area, mainly occupied by sugarcane. In these areas, the average estimated soil loss rate of 58 Mg ha-1 year-1 is equivalent to nearly four times the indicated average upper tolerance limit. In the remaining areas occupied by forest, riparian vegetation, afforestation and pasture, the estimated soil loss rates are low, around 2 Mg ha-1 year-1 , below the tolerance values. The model factor sensitivity analysis revealed that under the same weather condition (constant R factor), factors C and P (crop management and coverage and erosion control practices) defined the magnitude of the soil losses, whether in units, tens or hundreds of Mg ha-1 year-1. For a same category of land use (factors C and P constant), the LS factor (topographic) explained most of the observed variation. The results obtained from a simulation showed that the estimates were much less influenced by the K (soil erodibility) than by the topographic factor. The application of USLE permitted an estimation of expected soil erosion in the study area. The use of geotechnological and geostatistical analysis methods seems to be a promising approach in erosion studies.
Electrospun poly(lithium 2-acrylamido-2-methylpropanesulfonic acid) fiber-based polymer electrolytes for lithium-ion batteries

Novel single-ion conducting polymer electrolytes based on electrospun poly(lithium 2-acrylamido-2-methylpropanesulfonic acid) (PAMPSLi) membranes were prepared for lithium-ion batteries. The preparation started with the synthesis of polymeric lithium salt PAMPSLi by free-radical polymerization of 2-acrylamido-2-methylpropanesulfonic acid, followed by ion-exchange of H+ with Li+. Then, the electrospun PAMPSLi membranes were prepared by electrospinning technology, and the resultant PAMPSLi fiber-based polymer electrolytes were fabricated by immersing the electrospun membranes into a plasticizer composed of ethylene carbonate and dimethyl carbonate. PAMPSLi exhibited high thermal stability and its decomposition did not occur until 304°C. The specific surface area of the electrospun PAMPSLi membranes was raised from 9.9 m2/g to 19.5 m2/g by varying the solvent composition of polymer solutions. The ionic conductivity of the resultant PAMPSLi fiber-based polymer electrolytes at 20°C increased from 0.815 × 10−5 S/cm to 2.12 × 10−5 S/cm with the increase of the specific surface area. The polymer electrolytes exhibited good dimensional stability and electrochemical stability up to 4.4 V vs. Li+/Li. These results show that the PAMPSLi fiber-based polymer electrolytes are promising materials for lithium-ion batteries. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Electrical Conductivity of Single Crystals of MgO

The electrical conductivity of magnesium oxide at temperatures in the region of 1300°C is observed to depend upon the partial pressure of oxygen surrounding the sample. The conductivity increases at oxygen pressures both higher and lower than 10—5 atmospheres. At this pressure the conductivity is a minimum. This effect is increased as the iron content is increased and is almost absent in the purest samples.The conductivity is electronic rather than ionic and the number of charge carriers is controlled by the number of lattice vacancies. The dependence of conductivity on oxygen pressure may be satisfactorily explained by changes in stoichiometry and thus lattice defects in magnesium oxide. These changes in stoichiometry are larger when the magnesium oxide is contaminated with a variable valence impurity like iron than when it is pure.If an explanation based on iron changing valance state is accepted, then it may be demonstrated by an analysis of the chemical equilibria involved that anion deficiencies must.
Crystalline-to-amorphous transformation of cellulose in hot and compressed water and its implications for hydrothermal conversion

The behaviour of cellulose was studied in water at high temperatures and high pressures by in situ high-resolution optical microscopy. It was found that crystalline cellulose underwent transformation to an amorphous state in hot and compressed water, which was followed by complete dissolution. The finding shows that the chemical stability of cellulose in hot and compressed water is determined by the unique properties of cellulose that arise from extensive networks of hydrogen bonds among the cellulose chains in the crystal. The implications of the observation for hydrothermal conversion of cellulose are discussed.
FLUID-PARTICLE INTERACTIONS AND FLOW CHARACTERISTICS OF FLUIDIZED BEDS AND SETTLING SUSPENSIONS OF SPHERICAL PARTICLES

Abstract The published correlations for the velocity-voidage relationship observed during fluidization and sedimentation of uniformly sized spherical particles in solid-liquid systems are compared with published experimental results. It is found that the expression suggested by Richardson and Zaki represents the experimental data well over a wide range of values of Galileo number (10−2 < Ga< 1010) and voidage (0·4 < ϵ < 1). Methods are given for predicting the constants in the expression as a function of the properties of the system, including wall effects.