Miracle-dz/UniFAR-FTUs huggingface dataset:
Du désordre conformationnel des protéines structurées et intrinsèquement désordonnées par résonance magnétique nucléaire

Les macromolecules biologiques sont, par essence, des systemes dynamiques. Si l'importance de cette ﬂexibilite est maintenant clairement etablie, la caracterisation precise du desordre conformationnel de ces systemes reste encore une question ouverte. La resonance magnetique nucleaire constitue un outil unique pour sonder ces mouvements au niveau atomique que ce soit par les etudes de relaxation de spin ou par l'analyse des couplages dipolaires residuels. Ces derniers permettent d'etudier l'ensemble des mouvements ayant lieu a des echelles de temps plus rapide que la milliseconde, englobant ainsi les temps caracteristiques de nombreux mouvements physiologiquement importants. L'information contenue dans ces couplages residuels est ici interpretee principalement grâce a des approches analytiques pour quantiﬁer la dynamique presente dans des proteines repliees, determiner l'orientation de ces mouvements et obtenir de l'information structurale au sein de ce desordre conformationnel. Ces approches analytiques sont complementees par des methodes numeriques, permettant ainsi soit d'observer les phenomenes sous un autre angle, soit d'examiner d'autres systemes tels que les proteines intrinsequement desordonnees. L'ensemble de ces etudes laisse transparaitre une importante complementarite entre ordre structural et desordre conformationnel.
The Effect of Process Variables in Chlorine Dioxide Prebleaching of Birch Kraft Pulp. Part 2. AOX and OX Formation

Abstract Chlorine dioxide prebleaching (D0-stage) is known to produce some chlorinated organic compounds. This article presents the development of AOX and OX as a function of time under various prebleaching conditions for oxygen delignified hardwood pulp. It was observed that OX is formed more rapidly than AOX and its amount was less affected by a preceding A-stage. Temperature had little effect on chlorination. Using mill filtrate instead of water for dilution increased the amount of AOX formed while the amount of OX remained unchanged. Higher charges of chlorine dioxide expectedly increased chlorination during a D0-stage.
THE EFFECTIVE VISCOSITY AND EFFECTIVE DIFFUSIVITY OF BUBBLES IN AN AIR-WATER VERTICAL BUBBLING JET

The effective viscosity νe and the effective diffusivity of bubbles De in a vertical bubbling jet in a cylindrical bath were determined from the governing equations based on the boundary layer approximation and the Boussinesq approximation. These approximations were satisfied in the buoyancy region in the vertical bubbling jet. Gas holdup and mean bubble rising velocity needed in calculations of νe and De were measured with a two-element electro-resistivity probe, and the mean velocity of water with a laser Doppler velocimeter. The values of νe and De were almost the same on the jet axis in the buoyancy region and increased with an increase in the injected gas flow rate. The radial profile of νe was parabolic and that of De was almost uniform across the bubbling jet. The profile of νe was different from the profile of νe in a single-phase turbulent free jet.
The redox and complexation chemistry of iron within freshwater sources to the ocean : rivers, rain and glaciers

In Fe-limited or Fe-stressed waters Fe(II) cycling is an important feature of Fe biogeochemistry because processes favouring Fe(II) production or stability always expand the pool of Fe available to aquatic microorganisms. However almost nothing is known about Fe(II) organic speciation in natural waters and this limits our understanding of how this metal ion may interact with biological Fe uptake systems. Therefore I investigate how organic material affects Fe(II) biogeochemistry in rainwater, riverwater and in suspensions of aged glacial particulates. We compare Fe(II) concentrations (12-3600 nM) and, by adapting a ferrozine based reverse titration technique, ligand binding constants (logKFe(II) The weak (logKFe(II) <8), terrestrially derived ligands we report in 4 temperate/sub-tropical river systems are likely to be found in most surface freshwater systems, but their impact in higher salinity coastal seawater will be minimal. Stronger Fe(II) ligands (logKFe(II) 11) associated with effluent emissions however may exert a stabilising effect on Fe(II) concentrations in the natural environment. This may result in localised increases in bioavailable Fe concentrations and have implications for aquatic ecosystems in industrialised areas.
Dipalmitoyl-lecithin: assignment of the 1H and 13C nuclear magnetic resonance spectra, and conformational studies

The 13C resonances of the glycerol and choline groups of dipalmitoyl-lecithin in CD3OD, CDCl3, and D2O have been assigned from the 14N–13C and 31P–13C coupling constants, and proton decoupling studies on the assigned 1H spectra. Well-defined solvent effects are observed, but the chemical shifts for dipalmitoyl-lecithin in bilayers in D2O are very similar to the shifts of the corresponding resonances in biological membranes. From an analysis of the 1H spectrum of the CH2 multiplet in the CH–CH2OCOR fragment, the two vicinal coupling constants were extracted and used to calculate rotamer populations from a Karplus treatment. In a high proportion of the molecules of dipalmitoyl-lecithin in CD3OD and in CDCl3 the fatty acid chains are arranged gauche to each other, suggesting the presence of strong hydrophobic interactions. From an AA′BB′ analysis of the choline –CH2·CH2–fragment in dipalmitoyl-lecithin observed vicinal coupling constants indicate a similar conformation to that found in choline derivatives where an electrostatic interaction between the N+ and the O atoms leads to the conformation being exclusively in the gauche+N/O form.
Supplementing prediction by EuroSCORE with social and patient‐reported measures among patients undergoing cardiac surgery

The risk of poor outcomes is traditionally attributed to biological and physiological processes in cardiac surgery. However, evidence exists that other factors, such as emotional, behavioral, social, and functional, are predictive of poor outcomes. Objectives were to evaluate the predictive value of several emotional, social, functional, and behavioral factors on four outcomes: death within 90 days, prolonged stay in intensive care, prolonged hospital admission, and readmission within 90 days following cardiac surgery.
Investigation of Hydro-Geochemical Characteristics of Groundwater In Port Harcourt City, Nigeria: Implication for Use and Vulnerability

A hydrogeochemical evaluation of groundwater in Port Harcourt City, Southern Nigeria has been carried out. Thirty two (32) groundwater samples were analysed for their physical, chemical and microbiological properties. The average temperature of the groundwater samples is 29 oC, The water is slightly acidic with pH values between 4.28 – 7.72. Elevated Electrical Conductivity (EC) values in some coastal wells suggest possible pollution by seawater. The study also reveals saltwater contamination in the area as Chloride contents in some boreholes are up to 710.00mg/l. Besides of the major chemical compositions, ionic ratio (HCO 3 /Cl, Na/Ca, Ca/Cl, Mg/Cl and Ca/SO 4 ) was used to delineate saline water intrusion. Iron and Manganese concentrations are above the World Health Organization guide value in majority of the boreholes studied, with maximum value up to 1.60mg/l in Abuloma area. Constituents of the heavy metals as shown in this study reveal that, in some locations, values are slightly higher than the permissible levels. Microbial analysis of the water samples to determine the presumptive coliform count of the water indicates the presence of coliform bacteria in majority of the analysed samples, indicating anthropogenic contamination of groundwater. The water is generally classified as soft and fresh based on its hardness and Total Dissolved Solids (TDS), which ranges from 2.50mg/l – 142mg/l and 2.60mg/l – 401mg/l, respectively. The analytical results present the abundance of the ions in the following order: Mg > Ca > Na > K = Cl > SO 4 > HCO 3 > NO 3 . Chloride is the dominant anion found in the groundwater of the study area. Piper trilinear diagram for the study area shows that there is a mixture of two types of water with variable concentrations of major ions. These are Ca – Mg –Cl – SO 4 type and Na + K – Cl – SO 4 type water. The second water type is also influenced by NO3. This means that groundwater in the area is mainly made up of mixtures of earth alkaline and alkaline metals and predominantly Cl- -SO 4 2-water type. Most of the water samples are made up of mixtures of the two water types. The study provides the basic tool for sustainable groundwater management in the area in the context of quality assessment. @JASEM J. Appl. Sci. Environ. Manage . Sept, 2011, Vol. 15 (3) 479 -488
Brain parcellation driven by dynamic functional connectivity better capture intrinsic network dynamics

Until now, dynamic functional connectivity (dFC) based on functional magnetic resonance imaging is typically estimated on a set of predefined regions of interest (ROIs) derived from an anatomical or static functional atlas which follows an implicit assumption of functional homogeneity within ROIs underlying temporal fluctuation of functional coupling, potentially leading to biases or underestimation of brain network dynamics. Here, we presented a novel computational method based on dynamic functional connectivity degree (dFCD) to derive meaningful brain parcellations that can capture functional homogeneous regions in temporal variance of functional connectivity. Several spatially distributed but functionally meaningful areas that are well consistent with known intrinsic connectivity networks were identified through independent component analysis (ICA) of time‐varying dFCD maps. Furthermore, a systematical comparison with commonly used brain atlases, including the Anatomical Automatic Labeling template, static ICA‐driven parcellation and random parcellation, demonstrated that the ROI‐definition strategy based on the proposed dFC‐driven parcellation could better capture the interindividual variability in dFC and predict observed individual cognitive performance (e.g., fluid intelligence, cognitive flexibility, and sustained attention) based on chronnectome. Together, our findings shed new light on the functional organization of resting brains at the timescale of seconds and emphasized the significance of a dFC‐driven and voxel‐wise functional homogeneous parcellation for network dynamics analyses in neuroscience.
Speech intelligibility test methodology applied to powered air-purifying respirators used in healthcare

Abstract Powered air-purifying respirators (PAPRs) are worn to protect workers from hazardous respiratory exposures in a wide range of workplaces, including healthcare. However, PAPRs may diminish the ability of wearers to correctly hear words spoken by others, potentially interfering with safe performance of healthcare duties. Accordingly, the impact of PAPRs during healthcare use on speech intelligibility (SI) and consequently on user safety, usability, and patient care is not well studied. The objectives of this study were to (1) determine a listener’s ability to comprehend single-syllable words spoken by a PAPR wearer; (2) determine a PAPR wearer’s ability to intelligibly hear and identify single-syllable words spoken by a PAPR wearer; (3) to assess the variability between speakers, listeners, and PAPR models; (4) to investigate the effects of PAPR design features on SI; and (5) inform a SI requirement for certifying future PAPRs for use in healthcare. This study utilized a Modified Rhyme Test to assess SI for PAPRs. The current National Institute for Occupational Safety and Health (NIOSH) methods for assessing SI are limited to the recently introduced PAPR100 respirator class and the class of respirators claiming chemical, biological, radiological, and nuclear (CBRN) protections. Four NIOSH-approved PAPRs were evaluated using four human subjects. Four experimental conditions were examined:(1) Speaker and Listener with no PAPR; (2) Speaker and Listener both wearing PAPRs; (3) Speaker with a PAPR, Listener without a PAPR; and (4) Speaker without a PAPR, Listener with a PAPR resulted in a total of 144 experiments. Statistical analysis showed that the SI performance ratings were not significantly different among the PAPR models, but experimental conditions had significant impact on SI. The pattern of SI across the conditions of the experiment also showed a significant difference depending on PAPR model. The SI performance rating for all PAPRs could meet the current NIOSH CBRN certification requirement for speech intelligibility.
Estimation of Transfer Entropy for Capturing Connectivity and Causality in Industrial Processes

This paper discusses the use of two information theory measures: transfer entropy and direct transfer entropy, as an approach for detection of causality and connectivity between continuous variables in industrial processes (continuous systems). These measures are asymmetric and identify and quantify linear or non-linear directional relationships between two variables. To estimate these measures, we used estimators based on distances between neighbors. The results obtained from simulations demonstrate the applicability of the measurements and their estimations in order to identify the connectivity map of two systems: autoregressive model (which can be compared with the analytical results) and four water tanks (an industrial systems). Keywords— Transfer entropy, causality, continuous processes, industrial processes.
Influence of asymmetric dimethylarginine, hypoxia of inducible factor 1 alpha and connective tissue growth factor on the course of alcoholic cirrhosis of the liver against the background of exacerbation of chronic bronchitis

In patients with alcoholic liver cirrhosis a there was an increase of Asymmetric dimethylarginine, hypoxia induce factor -1α and connective tissue growth factor in the blood, especially in the exacerbation of chronic bronhitis, indicating an increase in endothelial dysfunction, hypoxia and activation of fibro- and angiogenesis in the background of increased inflammation. The positive correlations were detected between Asymmetric dimethylarginine, hypoxia induce factor -1α and the prognostic indeces ADC-MELD, CLIF-CACLF, CLIF-SOFA; they indicate their unfavourable effect on the alcoholic liver cirrhosis course and the threat of acute on chronic liver failure formation.
Theoretical Prediction of Expansion History of Metal Cylinder for Multicomponent Explosives

As a traditional experimental approach, the cylinder test has been widely applied to evaluate the ability to accelerate metal, acquire the specific dynamic energy, and calibrate the equation of state of the detonation product for an explosive. In this article, based on the constant metal-density Gurney formula, a theoretical approach to predicting the expansion history of a metal cylinder shell driven by the detonation product of a multicomponent explosive under any explosive mixture ratio is proposed, providing that the corresponding theoretical density and the initial internal energy and the Jones-Wilkins-Lee parameters of each explosive component in the multicomponent explosive are known. Based on this predicted expansion history, the ability to accelerate metal, the specific dynamic energy, and the equation of state of a multicomponent explosive under any explosive mixture can all be acquired without an extra cylinder test for the multicomponent explosive itself. For verification, numerical results for the expansion histories of a copper cylinder driven by the detonation products of a PBX-C03 and a Comp-B multicomponent explosive were calculated and found to be in reasonably good agreement with previous cylinder test data.
DSC and TMA Studies of Polysaccharide Physical Hydrogels

Various kinds of polysaccharides found in a wide variety of plants, bacteria, crustaceans and insects form hydrogels via physical aggregation in aqueous media. The major mass of hydrogels is water filled, ca. 95–99.5%, in a network structure, although the solid shape of the gel is maintained. In this paper, firstly the wide range of gelation mechanisms are briefly described, and then the thermal analysis of representative gel-forming polysaccharides, such as carrageenan, alginate, galactomannan, and pectin, is introduced. By differential scanning calorimetry (DSC), gel-sol and the sol-gel transition temperature of thermoreversible hydrogels are measured and phase diagram is established. It is suggested that binary systems showing sinusoidal gel-sol-gel transition are capable of being assembled. By thermomechanical analysis (TMA), the dynamic modulus ( E ′) at around 1 × 10^4 Pa of thermo-irreversible hydrogels was obtained using a sample holder designed to measure the viscoelastic properties in water. Reliable coordination is shown between the results obtained by DSC and TMA. In this review, the current research and several topics on concerning the thermal properties of polysaccharide physical hydrogels are introduced.
Differential Kinetic Determination of Mixtures of Aniline and Its Derivatives Using N, N-Dimethyl-p-phenylenediamine

The oxidative coupling reaction between the quinonediimine (QDI) of N, N-dimethyl-p-phenylenediamine (DMPD) and aromatic amines was utilized for the simultaneous determination of binary mixtures of aniline and its derivatives by the differential reaction rate method. A mixture of oxidant and DMPD was used instead of QDI because QDI was unstable. The effects of pH and the oxidant (K3Fe (CN)6, K2Cr2O7 and their mixture) on the stability of the first oxidation product of DMPD, semiquinone (SQ), and on the equilibrium among DMPD, SQ and QDI, were investigated. The second-order rate constants of two amines reacting with QDI and the overall pseudo first-order rate constant of a mixture were determined from the slope of the straight line (the concentration of SQ vs. time) and by simplified complementary tristimulus colorimetry. Mixtures of amines down to 1.0×10-4M were determined. Most relative errors were in the range of 0 to 14%. Among the compounds examined for interference, phenols and carbonyl compounds showed serious effects.
Effect of electro-discharge circuit parameters on the destructive action of plasma channel in solid media

The results of computer blast-hole experiments with copper wire electro-explosion in the polyethylene-concrete media has been analyzed with shock and pressure wave dynamics depending on the spatiotemporal distribution of electrical power deposition in plasma channel. Pressure and stress-wave dynamics of tensely-deformed material state has been analysed by means of physical and mathematical model, which consistently describes the operation of the discharge circuit, plasma channel expansion, generation and propagation of the shock and pressure waves in the condensed media. It has been shown the significant dependence of the stress-wave profile on the pressure pulse wave shape on the borehole wall which is determined by the rate of electrical energy release in the plasma channel and is weakly depended on the time of energy release (at given rate of its release). Analysis of stress-wave dynamics have been shown that the rapid power deposition results to the higher amplitude of compressive stresses in the wave. The lower energy deposition rate in plasma channel leads to the higher amplitude of tensile stresses both in radial and tangential direction.
ASIC3 inhibition modulates inflammation-induced changes in the activity and sensitivity of Aδ and C fiber sensory neurons that innervate bone

The Acid Sensing Ion Channel 3 (ASIC3) is a non-selective cation channel that is activated by acidification, and is known to have a role in regulating inflammatory pain. It has pro-algesic roles in a range of conditions that present with bone pain, but the mechanism for this has not yet been demonstrated. We aimed to determine if ASIC3 is expressed in Aδ and/or C fiber bone afferent neurons, and to explore its role in the activation and sensitization of bone afferent neurons after acute inflammation. A combination of retrograde tracing and immunohistochemistry was used to determine expression of ASIC3 in the soma of bone afferent neurons. A novel, in vivo, electrophysiological bone-nerve preparation was used to make recordings of the activity and sensitivity of bone afferent neurons in the presence of carrageenan-induced inflammation, with and without the selective ASIC3 inhibitor APET×2. A substantial proportion of bone afferent neurons express ASIC3, including unmyelinated (neurofilament poor) and small diameter myelinated (neurofilament rich) neurons that are likely to be C and Aδ nerve fibers respectively. Electrophysiological recordings revealed that application of APET×2 to the marrow cavity inhibited carrageenan-induced spontaneous activity of C and Aδ fiber bone afferent neurons. APET×2 also inhibited carrageenan-induced sensitization of Aδ and C fiber bone afferent neurons to mechanical stimulation, but had no effect on the sensitivity of bone afferent neurons in the absence of inflammation. This evidence supports a role for ASIC3 in the pathogenesis of pain associated with inflammation of the bone.
Ethnic Disparities in Dental Caries among Adolescents in China

Comprehensive research on ethnic disparities in dental caries in China is limited. The aims of this cross-sectional study were to compare the levels of dental caries in adolescents between the Han ethnic group and ethnic minority groups in China and to explore the risk indicators for dental caries within ethnic subgroups. Data from the Fourth National Oral Health Survey in 2015, which covered all 31 province-level administrative divisions in mainland China, were used. The dental caries status in the permanent dentition of adolescents aged 12, 13, 14, and 15 y was measured using the decayed, missing, and filled teeth (DFMT) score, and sociodemographic characteristics and oral health–related behaviors were also collected. A total of 118,601 adolescents were included, with ethnic minority groups accounting for 13.15%. Of the Han and minority groups, the standardized prevalence of dental caries experience was 40.58% and 47.67%, and the mean DMFT scores were 0.97 and 1.28, respectively. According to the multivariate zero-inflated negative binomial regression analysis, the caries status of minorities was more severe than Han adolescents (adjusted prevalence rate ratio [PRR], 1.14; 95% confidence interval [CI], 1.10–1.18). This disparity was greater among adolescents who lived in rural areas, had mid-level economic status, and frequently consumed sugary beverages. After propensity score matchings, Uygur (PRR, 1.44; 95% CI, 1.25–1.67), Tibetan (PRR, 1.39; 95% CI, 1.3–1.48), and Yi (PRR, 1.24; 95% CI, 1.04–1.48) adolescents were significantly more likely to have caries than Han adolescents. Subgroup analyses revealed that gender, age, location of residence, economic status, region, consumption of sweet snacks and sugary beverages, and dental visit pattern were significantly associated with dental caries within ethnic minorities.