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As is already known, solar photovoltaic (PV) technology is a widely accepted technology for power generation worldwide. However, it is scientifically proven that its power output decreases with an increase in the temperature of the PV module. Such an important issue is controlled by adopting a number of cooling mechanisms for the PV module. The present experimental study assesses the effect of a fanless CPU heat pipe on the performance of a PV module. The experiment was conducted in June in real weather conditions in Yekaterinburg, Russian Federation. The comparative analysis of two PV panels (i.e., cooled, and uncooled) based on the electrical energy, exergy performance, economic, embodied energy and energy payback (5E) for the two systems is presented and discussed. The key results from the study are that the average temperature reduction from the cooling process is 6.72 °C. The average power for the cooled panel is 11.39 W against 9.73 W for the uncooled PV panel; this represents an increase of 1.66 W for the cooled module. Moreover, the average improvements in the electrical efficiency, and embodied energy recorded for a cooled PV panel 2.98%, and 438.52 kWh, respectively. Furthermore, the calculations of the levelized cost of energy (LCE) for the cooled PV panel indicate that it can range from 0.277–0.964 USD/kWh, while that for the uncooled PV panel also ranges from 0.205–0.698 USD/kWh based on the number of days of operation of the plant. © 2022 by the authors. Y848041; National Natural Science Foundation of China, NSFC: 41761144079, 42150410393; Chinese Academy of Sciences, CAS: 2021PC0002, XDA20060303; Ministry of Education and Science of the Russian Federation, Minobrnauka: FEUZ-2022-0031; K. C. Wong Education Foundation: GJTD-2020-14 This research was funded by the Strategic Priority Research Program of the Chinese Academy of Sciences, the Pan-Third Pole Environment Study for a Green Silk Road (Grant No. XDA20060303), the Research Fund for International Scientists of the National Natural Science Foundation of China (Grant No. 42150410393), the International Cooperation Project of the National Natural Science Foundation of China (Grant No. 41761144079), the CAS PIFI Fellowship (Grant No. 2021PC0002), the K.C. Wong Education Foundation (Grant No. GJTD-2020-14), and the Xinjiang Tianchi Hundred Talents Program (Grant No. Y848041). The research funding from the Ministry of Science and Higher Education of the Russian Federation (Ural Federal University Program of Development within the Priority-2030 Program) is gratefully acknowledged: Grant number: FEUZ-2022-0031.

6 Pág. Centro de Biotecnología y Genómica de Plantas (CBGP), Synteny conservation analysis is a well-established methodology to investigate the potential functional role of unknown prokaryotic genes. However, bioinformatic tools to reconstruct and visualise genomic contexts usually depend on slow computations, are restricted to narrow taxonomic ranges, and/or do not allow for the functional and interactive exploration of neighbouring genes across different species. Here, we present GeCoViz, an online resource built upon 12 221 reference prokaryotic genomes that provides fast and interactive visualisation of custom genomic regions anchored by any target gene, which can be sought by either name, orthologous group (KEGGs, eggNOGs), protein domain (PFAM) or sequence. To facilitate functional and evolutionary interpretation, GeCoViz allows to customise the taxonomic scope of each analysis and provides comprehensive annotations of the neighbouring genes. Interactive visualisation options include, among others, the scaled representations of gene lengths and genomic distances, and on the fly calculation of synteny conservation of neighbouring genes, which can be highlighted based on custom thresholds. The resulting plots can be downloaded as high-quality images for publishing purposes. Overall, GeCoViz offers an easy-to-use, comprehensive, fast and interactive web-based tool for investigating the genomic context of prokaryotic genes, and is freely available at https://gecoviz.cgmlab.org., National Programme for Fostering Excellence in Scientific and Technical Research [PGC2018-098073-A-I00 MCIU/AEI/FEDER, UE to J.HC., J.JL.]; ‘la Caixa’ Foundation [100010434, fellowship code LCF/BQ/DI18/11660009 to A.R.dR.]; European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie [713673].

International audience; We report on the observation of a transverse Doppler shift in the optical domain. It occurs when a receiving system travels perpendicularly to the propagation direction of a Gaussian beam. Shifts of a few tens of Hz have been evidence for a detector moving in the mm/s range. The shift increases as the detector is far from the beam axis. The observations fully agree with theoretical calculations on the propagation of Gaussian beams. It can be observed for any kind of waves, including radio and acoustic waves. Practical consequences are then discussed, especially for techniques using Doppler measurements in microsystems.

For some values of the total angular momentum consistent with reaction, the title processes involve nonreactive trajectories proceeding through a single rebound mechanism during which the internal motion of the reagent diatom is nearly unperturbed. When such paths are in a significant amount, the classical reaction probability is found to be markedly lower than the quantum mechanical one. This finding was recently attributed to an unusual quantum effect called diffraction-mediated trapping, and a semiclassical correction was proposed in order to take into account this effect in the classical trajectory method. In the present work, we apply the resulting approach to the calculation of opacity functions as well as total and state-resolved integral cross sections (ICSs) and compare the values obtained with exact quantum ones, most of which are new. As the title reactions proceed through a deep insertion well, mean potential statistical calculations are also presented. Seven values of the collision energy, ranging from 30 to 1127 K, are considered. Two remarkable facts stand out: (i) The corrected classical treatment strongly improves the accuracy of the opacity function as compared to the usual classical treatment. When the entrance transition state is tight, however, those trajectories crossing it with a bending vibrational energy below the zero point energy must be discarded. (ii) The quantum opacity function, particularly its cutoff, is finely reproduced by the statistical approach. Consequently, the total ICS is also very well described by the two previous approximate methods. These, however, do not predict state-resolved ICSs with the same accuracy, proving thereby that (i) one or several genuine quantum effects involved in the dynamics are missed by the corrected classical treatment and (ii) the dynamics are not fully statistical.

In this study, we have synthesized B doped Ca5(PO4)3OH (HAP) by a sonication chemical method. The thermoluminescence (TL) properties of the family of synthesized samples (B doped Ca5(PO4)3OH (HAP) were investigated using an IRSL-TL 565 nm filter. This gave the highest TL intensity of each phosphor after 2 Gy beta-irradiation. Three TL glow peaks of B doped Ca5(PO4)3OH (HAP) are centered at around 84, 208 and 324 degrees C (with a heating rate of 2 degrees Cs-1). The trapping parameters such as activation energy (E), order of kinetics (b), frequency factor (s) were calculated by using initial rise (IR), various heating rates (VHR) and computerized glow curve deconvolution (CGCD) method. The response of TL glow curves remained constant within +/- 5% deviation from the initial value after 9 cycles of reuse; but only at tenth cycle the deviation goes up to 6%.

We report structural and computational studies of three α-aminophosphonates 4-XC6H4–NH–CH(4-BrC6H4)–P(O)(OiPr)2, namely diisopropyl((4-bromophenyl)(phenylamino)methyl)phosphonate (X = H, 1), diisopropyl((4-bromophenyl)((4-bromophenyl)amino)methyl)phosphonate (X = Br, 2) and diisopropyl((4-bromophenyl)((4-methoxyphenyl)amino)methyl)phosphonate (X = MeO, 3). The structures of 1–3 were fully confirmed by means of the 31P{1H} and 1H NMR spectroscopy. Crystal structures of 2 and 3 are isostructural and each contain two independent molecules in the asymmetric unit cell. Energy frameworks have been calculated to analyze the overall crystal packing of 1–3. The DFT calculations were performed to verify the structures of 1–3 as well as their electronic and optical properties. Molecular docking was applied to examine the influence of both the (S)- and (R)-enantiomers of 1–3 on a series of the SARS-CoV-2 proteins. © 2021 Elsevier Ltd.

The branching fraction of the rare B-s(0) -> phi mu(+)mu(-) decay is measured using data collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV, corresponding to integrated luminosities of 1, 2, and 6 fb(-1), respectively. The branching fraction is reported in intervals of q(2), the square of the dimuon invariant mass. In the q(2) region between 1.1 and 6.0 GeV2/c(4) , the measurement is found to lie 3.6 standard deviations below a standard model prediction based on a combination of light cone sum rule and lattice QCD calculations. In addition, the first observation of the rare B-s(0)-> f(2)' (1525)mu(+)mu(-) decay is reported with a statistical significance of 9 standard deviations and its branching fraction is determined.

We present the implementation of a fully coupled polarizable QM/MM/continuum model based on the AMOEBA polarizable force field and the domain decomposition implementation of the conductor-like screening model. Energies, response properties, and analytical gradients with respect to both QM and MM nuclear positions are available, and a generic, atomistic cavity can be employed. The model is linear scaling in memory requirements and computational cost with respect to the number of classical atoms and is therefore suited to model large, complex systems. Using three variants of the green-fluorescent protein, we investigate the overall computational cost of such calculations and the effect of the continuum model on the convergence of the computed properties with respect to the size of the embedding. We also demonstrate the fundamental role of polarization effects by comparing polarizable and nonpolarizable embeddings to fully QM ones.

The study is aimed at investigating the radiative properties of soot aggregates at determined morphological features using both experimental and numerical methods. Soot aggregates collected from air monitoring stations in different locations were examined. The locations were divided into three groups. The first group (Case 1) included the coastal and industrial zone; the second group (Case 2) consisted of small and large cities; and the third group (Case 3) included areas in the neighbourhood of thermal power plants. The absorbance measurements of the soot aggregates were conducted in the visible and near-infrared spectra, and in the wavelength range of 2 μm-20 μm. The samples were characterised by scanning electron microscopy (SEM), and their radiative properties were assessed using the discrete dipole approximation (DDA) for numerically generated fractal aggregates with two popular refractive indices of m = 1.60 + 0.60i and m = 1.90 + 0.75i. Calculations were conducted for primary particles in point-contact, with 20% overlapping and with a coating (50% and 80%) in the wavelength range of 0.4–1.064 μm. The largest measured absorbance values in both the winter and summer seasons were found in the cities in Case 1, and the x-ray diffraction (XRD) phases of the samples were also presented. The radiative properties of the aggregates, i.e., Df = 1.78 and kf = 2.0 representing Case 3, were close to those of aggregates with Df = 2.1 and kf = 2.35 representing Case 1 in the investigated wavelength range. The calculated radiative properties and the experimental absorbance measurements for point-contact and overlapping situations showed the same trend in the examined wavelengths. The absorbance properties of the samples of coastal and industrial zones were distinctively higher than others in the wavelength range of 2 μm-20 μm which could be attributed to the PAH effects.

DFT (VASP) and semi-empirical (HyperChem) calculations for the l- and d-chiral diphenylalanine (l-FF and d-FF) nanotube (PNT) structures, empty and filled with water/ice clusters, are presented and analyzed. The results obtained show that after optimization, the dipole moment and polarization of both chiral type l-FF and d-FF PNT and embedded water/ice cluster are enhanced; the water/ice cluster acquire the helix-like structure similar as l-FF and d-FF PNT. Ferroelectric properties of tubular water/ice helix-like-cluster obtained after optimization inside l-FF and d-FF PNT and total l-FF and d-FF PNT with embedded water/ice cluster are discussed. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature. This work was partially supported by the Fundacão para a Ciência e a Tecnologia(FCT, Portugal) through project UID/CTM/50025/2013 and UIDB/50011/2020 & UIDP/50011/2020. P.Z. and S.K. are grateful to the FCT (Portugal) through the project “BioPiezo,” PTDC/CTM–CTM/31679/2017 (CENTRO-01-0145-FEDER-031679). The computational parts of the study was completed within the framework of the non-commercial Agreement on scientific-technical cooperation between Institute of Mathematical Problems of Biology (IMPB) of the Keldysh Institute of Applied Mathematics RAS (KIAM RAS) and Department of Physics and I3N Institution of the University of Aveiro, Portugal.

Background: Increasing cancer drug prices are a challenge for patients and health systems in the USA and Europe. By contrast with the USA, national authorities in European countries often directly negotiate drug prices with manufacturers. The American Society of Clinical Oncology (ASCO) and the European Society for Medical Oncology (ESMO) developed frameworks to evaluate the clinical value of cancer therapies: the ASCO-Value Framework (ASCO-VF) and the ESMO-Magnitude of Clinical Benefit Scale (ESMO-MCBS). We aimed to assess the association between the clinical benefit of approved cancer drugs based on these frameworks and their drug prices in the USA and four European countries (England, Switzerland, Germany, and France). Methods: For this cost–benefit analysis, we identified all new drugs with initial indications for adult cancers that were approved by the US Food and Drug Administration between Jan 1, 2009, and Dec 31, 2017, and by the European Medicines Agency up until Sept 1, 2019. For drugs indicated for solid tumours, we assessed clinical benefit using ASCO-VF and ESMO-MCBS. We compared monthly drug treatment costs between benefit levels using hierarchical linear regression models, and calculated Spearman's correlation coefficients between costs and benefit levels for individual countries. Findings: Our cohort included 65 drugs: 47 (72%) drugs were approved for solid tumours and 18 (28%) were approved for haematological malignancies. The monthly drug treatment costs in the USA were a median of 2·31 times (IQR 1·79–3·17) as high as in the assessed European countries. There were no significant associations between monthly treatment costs for solid tumours and clinical benefit in all assessed countries, using the ESMO-MCBS (p=0·16 for the USA, p=0·98 for England, p=0·54 for Switzerland, p=0·52 for Germany, and p=0·40 for France), and for all assessed countries except France using ASCO-VF (p=0·56 for the USA, p=0·47 for England, p=0·26 for Switzerland, p=0·23 for Germany, and p=0·037 for France). Interpretation: Cancer drugs with low or uncertain clinical benefit might be prioritised for price negotiations. Value frameworks could help identify therapies providing high clinical benefit that should be made rapidly available across countries. Funding: Swiss Cancer Research Foundation (Krebsforschung Schweiz). © 2020 Elsevier Ltd

In this paper we describe the thermoluminescence (TL) characteristics of ZnB 2 O 4 :Pr 3+ phosphors with Pr concentrations varying between 0.2 and 1 mol% prepared by a wet-chemical method. The TL glow curves of the phosphor sample consisted of three peaks located at 71 °C (P1), 124 °C (P2) and 233 °C (P3). The TL intensity increased with the beta dose ranging from ~0.1 to ~20 Gy. Dose response, reproducibility and trapping parameters of TL glow curves were evaluated to clearly reveal thermoluminescence features. We observed that TL intensity of P2 and P3 peaks decreases as the heating rate increases. Trap parameters were estimated via the Hoogenstraaten, Booth-Bohun-Parfianovitch, the initial rise methods combined with T m -T stop experiment and TLanal CGCD program. Heating rates were varied to use in the Hoogenstraaten analyses. The T m -T stop investigations on regenerated TL signals for P1 and P2 peaks indicated that ZnB 2 O 4 :Pr 3+ phosphor has four electron trap levels with energy values in the range of 0.5–1.5 eV These four traps have first order kinetic and are formed at high temperature region. Resulting values are utilized as a reference for the CGCD procedure and the trapping parameters from the TL glow curves are calculated. The figure of merit (FOM) of the TL glow curve during curve fitting procedures is found to be 2.019%. The intensities of the main dosimetric peaks appeared at 124 °C and 233 °C exhibits good linear dose response up to 20 Gy. These results provide valuable knowledge for use of the characteristics of Pr doped ZnB 2 O 4 in dosimetry research, just need to eliminate low temperature TL peak. © 2019 Elsevier Ltd Çukurova Üniversitesi: FAY-2015-4735 This work was supported by the Research Fund of the Çukurova University, Turkey (Project Number: FAY-2015-4735 ).

First principles calculations of the magnetic and electronic properties of VSe2 describing the transition between two structural phases (H,T) were performed. The results of the calculations evidence a rather low energy barrier (0.60 eV for the monolayer) for the transition between the phases. The energy required for the deviation of a Se atom or whole layer of selenium atoms by a small angle of up to 10° from their initial positions is also rather low, 0.32 and 0.19 eV/Se, respectively. The changes in the band structure of VSe2 caused by these motions of Se atoms should be taken into account for analysis of the experimental data. Simulations of the strain effects suggest that the experimentally observed T phase of the VSe2 monolayer is the ground state due to substrate-induced strain. Calculations of the difference in the total energies of the ferromagnetic and antiferromagnetic configurations evidence that the ferromagnetic configuration is the ground state of the system for all stable and intermediate atomic structures. Calculated phonon dispersions suggest a visible influence of the magnetic configurations on the vibrational properties. This journal is © the Owner Societies.

Particle dispersions provide a promising tool for the engineering of functional materials that exploit self-assembly of complex structures. Dispersion made from magnetic colloidal particles is a great choice; they are biocompatible and remotely controllable among many other advantages. However, their dominating dipolar interaction typically limits structural complexity to linear arrangements. This paper shows how a magnetostatic equilibrium state with noncollinear arrangement of the magnetic moments, as reported for ferromagnetic Janus particles, enables the controlled self-organization of diverse structures in two dimensions via constant and low-frequency external magnetic fields. Branched clusters of staggered chains, compact clusters, linear chains, and dispersed single particles can be formed and interconverted reversibly in a controlled way. The structural diversity is a consequence of both the inhomogeneity and the spatial extension of the magnetization distribution inside the particles. We draw this conclusion from calculations based on a model of spheres with multiple shifted dipoles. The results demonstrate that fundamentally new possibilities for responsive magnetic materials can arise from interactions between particles with a spatially extended, anisotropic magnetization distribution. © 2019 American Physical Society.

A scaling theory of the Kondo lattices with frustrated exchange interactions is developed, criterium of antiferromagnetic ordering and quantum-disordered state being investigated. The calculations taking into account magnon and incoherent spin dynamics are performed. Depending on the bare model parameters, one or two quantum phase transitions into non-magnetic spin-liquid and Kondo Fermi-liquid ground states can occur with increasing the bare coupling constant. Whereas the renormalization of the magnetic moment in the ordered phase can reach orders of magnitude, spin fluctuation frequency and coupling constant are moderately renormalized in the spin-liquid phase. This justifies application of the scaling approach. Possibility of a non-Fermi-liquid behavior is treated., Comment: 11 pages, 6 figures, J.Phys.: Cond. Mat., accepted

Purpose of the research Although single nucleotide polymorphisms of membrane-spanning 4A (MS4A) (rs670139) and several other susceptibility genes have shown interaction effects on the risk of Alzheimer's disease (AD), little is known about the interaction effects of apolipoprotein E (APOE) with MS4A (rs670139) on cognitive performances, and the underlying pathogenesis is unclear. The study aimed to investigate the APOE-MS4A (rs670139) interaction effects on cognitive performances, cortical volumes, and functional connectivity (FC) in brain networks. Principal results Cognitive performances were characterized in each genotypic group, and were compared between normal controls and patients in each genotypic group. APOE-MS4A interaction effects on memory and executive function scores, cortical volumes, and FC in brain networks were demonstrated. Significant effects of APOE-MS4A interactions on FC were observed in executive control network (ECN) (T maxima = 4.99, false discovery rate-corrected p, Highlights • APOE-MS4A interactions affect executive control network (ECN) and calculation score. • Calculation score is correlated with functional connectivity in ECN. • Variation in ECN is associated with genetic effects on calculation performances. • The calculation score is correlated with each frontal volume. • Genotypic variation affects the relationship between calculation and frontal volume.

The main objective of this study was to analyze the carbon footprint (CF) of grazing dairy goat systems in a natural park according to their grazing level. A total of 16 representative grazing goat farms in southern Spain were selected and grouped into three farming systems: low productivity grazing farms (LPG), more intensified grazing farms (MIG) and high productivity grazing farms (HPG). Their CF was analyzed, including greenhouse gas emissions and soil C sequestration according to the farms grazing level and milk productivity, taking into account different functional units (one kilogram of fat and protein corrected milk (FPCM) and one hectare) and milk correction. Results showed that all variables differed according to the milk correction applied as the values for cow's milk correction were 41% lower than for sheep's milk correction. Total emissions and contributions of soil carbon sequestration differed according to farming system group; LPG farms had higher total emissions than MIG and HPG farms, however total carbon sequestration was lower in the MIG farms than in the LPG and HPG farms. The CF values ranged from 2.36 to 1.76 kg CO2e kg-1 FPCM for sheep's milk correction and from 1.40 to 1.04 kg CO2e kg-1 FPCM for cow's milk correction. No differences were found between farming system groups in either of the two cases but when calculations took hectare of land as a functional unit, the contribution of MIG farms to the CF was 85% higher than LPG and HPG farms. Therefore it is important to take into account the functional unit used to calculate the CF by analyzing this indicator in a broader context, and including carbon sequestration by grazing livestock in the calculation. In order to reduce the CF of this type of system, it is advisable to make appropriate use of the natural resources and to reach an optimum level of milk productivity, high enough for pastoral livestock farming to be viable. © 2018 Elsevier Ltd The authors thank the “ Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria ” (Project INIA- RTA2010-00064-C04-02 ) for funding this research. The authors also acknowledge the INIA and the European Social Fund pre-doctoral contract grant (Rosario Gutiérrez Peña) and would especially like to thank the goat farmers for their contribution.

Studying extreme events and how they evolve in a changing climate is one of the most important current scientific challenges. Starting from complex climate models, a key difficulty is to be able to run long enough simulations in order to observe those extremely rare events. In physics, chemistry, and biology, rare event algorithms have recently been developed to compute probabilities of events that cannot be observed in direct numerical simulations. Here we propose such an algorithm, specifically designed for extreme heat or cold waves, based on statistical physics approaches. This gives an improvement of more than two orders of magnitude in the sampling efficiency. We describe the dynamics of events that would not be observed otherwise. We show that European extreme heat waves are related to a global teleconnection pattern involving North America and Asia. This tool opens a full range of studies, so far impossible, aimed at assessing quantitatively climate change impacts., Proceedings of the National Academy of Sciences (2017)

The effect of heating rate (HR) on thermoluminescence (TL) glow curves of 1%, 4%, and 10% Ce-3 (+) doped ZnB2O4 phosphors was investigated in detail. The glow peaks are examined and, activation energy (E) and frequency factor (s) are determined by using various heating rate (VHR) method. In the obtained glow curves with nine different HRs between 2 and 10 degrees C/s, it was observed that the TL intensities of the first peaks of all three samples and the second peak of 10% Ce-3 (+) doped sample decrease with increasing HR. The decrease in TL intensity was investigated whether it may be due to the presence of thermal quenching or not. On the other hand, the second glow peaks of 1, 4% Ce-3 (+) doped ZnB2O4 phosphors show an anomalous TL behavior, which the probability of the radiative processes increases due to recombination of free electrons, so the TL intensity increases with the HR. The graphs of full width at the half maximum (FWHM) versus HR were also plotted to evaluate the influence of HR on TL intensity. In this paper, we suggest that the non-localized Schon - Klasens model may give an explanation for the second peaks of 1, 4% Ce-3 (+) doped ZnB2O4 phosphors showing an unexpected increase with the increasing HR. In addition, the calculated E values of all doped phosphors were found similar in the range of 0.47-0.53 eV for peak 1 and 0.61-0.66 eV for peak 2. However, s values of Ce-3 (+) doped ZnB2O4 phosphors were found slightly different according to the dopant amount and the equation used. Furthermore, different amount of Ce-3 (+) doped samples indicate the similar properties for the repeated cycles of 5 Gy in the same irradiation conditions.

New copper(II) complexes-dimeric-[Cu(nphen)(gly)(H2O)](+) (1) and [Cu(dmphen)(gly)(NO3)(H2O)] (2) (nphen = 5-nitro-1,10-phenanthroline, dmphen = 4,7-dimethyl-1,10-phenanthroline, and gly = glycine)-have been synthesized and characterized by CHN analysis, single-crystal X-ray diffraction techniques, FTIR, EPR spectroscopy, and cyclic voltammetry. The CT-DNA-binding properties of these complexes have been investigated by thermal denaturation measurements and both absorption and emission spectroscopy. The DNA cleavage activity of these complexes has been studied on supercoiled pUC19 plasmid DNA by gel electrophoresis experiments in the absence and presence of H2O2. Furthermore, the interaction of these complexes with bovine serum albumin (BSA) has been investigated using absorption and emission spectroscopy. The thermodynamic parameters, free-energy change (Delta G), enthalpy change (Delta H), and entropy change (Delta S) for BSA + complexes 1 and 2 systems have been calculated by the van't Hoff equation at three different temperatures (293.2, 303.2, and 310.2 K). The distance between the BSA and these complexes has been determined using fluorescence resonance energy transfer (FRET). Conformational changes of BSA have been observed using the synchronous fluorescence technique. In addition, in vitro cytotoxicities of these complexes on tumor cell lines (Caco-2, A549, and MCF-7) and healthy cells (BEAS-2B) have been examined. The antimicrobial activity of the complexes has also been tested on certain bacteria cells. The effect of mono and dimeric in the above complexes is presented and discussed. New copper(II) complexes-dimeric-[Cu(nphen)(gly)(H2O)](+) (1) and [Cu(dmphen)(gly) (NO3)(H2O)] (2) (nphen = 5-nitro-1,10-phenanthroline, dmphen = 4,7-dimethyl-1,10-phenanthroline and gly = glycine)-have been synthesized and characterized by CHN analysis, single-crystal X-ray diffraction techniques, FTIR and EPR spectroscopy. They have been tested for their in vitro DNA/BSA interactions by the spectroscopic methods. These complexes exhibited higher cytotoxic and antimicrobial activities. Complex 1 shows better DNA / BSA interactions in comparison to complex 2.

The present report introduces a novel module of the QuBiLS-MIDAS software for the distributed computation of the 3D Multi-Linear algebraic molecular indices. The main motivation for developing this module is to deal with the computational complexity experienced during the calculation of the descriptors over large datasets. To accomplish this task, a multi-server computing platform named Tarenal was developed, which is suited for institutions with many workstations interconnected through a local network and without resources particularly destined for computation tasks. This new system was deployed in 337 workstations and it was perfectly integrated with the QuBiLSMIDAS software. To illustrate the usability of the T-arenal platform, performance tests over a dataset comprised of 15000 compounds are carried out, yielding a 52 and 60 fold reduction in the sequential processing time for the 2-Linear and 3-Linear indices, respectively. Therefore, it can be stated that the T-arenal based distribution of computation tasks constitutes a suitable strategy for performing high-throughput calculations of 3D Multi-Linear descriptors over thousands of chemical structures for posterior QSAR and/or ADME-Tox studies. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA.

The benefits of protein structure refinement in water are well documented. However, performing structure refinement with explicit atomic representation of the solvent molecules is computationally expensive and impractical for NMR-restrained structure calculations that start from completely extended polypeptide templates. Here we describe a new implicit solvation potential, EEFx (Effective Energy Function for XPLOR-NIH), for NMR-restrained structure calculations of proteins in XPLOR-NIH. The key components of EEFx are an energy term for solvation energy that works together with other nonbonded energy functions, and a dedicated force field for conformational and nonbonded protein interaction parameters. The initial results obtained with EEFx show that significant improvements in structural quality can be obtained. EEFx is computationally efficient and can be used both to fold and refine structures. Overall, EEFx improves the quality of protein conformation and nonbonded atomic interactions. Moreover, such benefits are accompanied by enhanced structural precision and enhanced structural accuracy, reflected in improved agreement with the cross-validated dipolar coupling data. Finally, implementation of EEFx calculations is straightforward and computationally efficient. Overall, EEFx provides a useful method for the practical calculation of experimental protein structures in a physically realistic environment.

A Monte Carlo simulation study has been conducted of 60Co photons Compton scattered in concrete, illustrating the degraded energy spectra of gamma-ray radiation. Results are produced representing a NaI(Tl) detector model. We were able to analyse energy distributions of photons that reach the detector system after suffering several successive Compton scatterings in the target. The predicted decrease in intensity of single- and multiple-scattering peaks with increase in thickness of the target medium are in good agreement with experimental observations and findings reported by others.

Meat processing wastewater sludge has high organic content but it is very slow to degrade in biological processes. Anaerobic digestion may be a good alternative for this type of sludge when the hydrolysis, known to be the rate-limiting step of biological sludge anaerobic degradation, could be eliminated by disintegration. This investigation deals with disintegration of meat processing wastewater sludge. Microwave (MW) irradiation and combined alkaline pretreatment and MW irradiation were applied to sludge for disintegration purposes. Disintegration performance of the methods was evaluated with disintegration degree based on total and dissolved organic carbon calculations (DD TOC), and the solubilization of volatile solids (S VS) in the pretreated sludge. Optimum conditions were found to be 140°C and 30 min for MW irradiation using response surface methodology (RSM) and pH=13 for combined pretreatment. While DD TOC was observed as 24.6% and 54.9, S VS was determined as 8.54% and 42.5% for MW pretreated and combined pretreated sludge, respectively. The results clearly show that pre-conditioning of sludge with alkaline pretreatment played an important role in enhancing the disintegration efficiency of subsequent MW irradiation. Disintegration methods also affected the anaerobic biodegradability and dewaterability of sludge. An increase of 23.6% in biogas production in MW irradiated sludge was obtained, comparing to the raw sludge at the end of the 35 days of incubation. This increase was observed as 44.5% combined pretreatment application. While MW pretreatment led to a little improvement of the dewatering performance of sludge, in combined pretreatment NaOH deteriorates the sludge dewaterability. © 2013 Copyright Taylor and Francis Group, LLC.

This work describes Cosmic Microwave Background (CMB) data analysis algorithms and their implementations, developed to produce a pixelized map of the sky and a corresponding pixel-pixel noise correlation matrix from time ordered data for a CMB mapping experiment. We discuss in turn algorithms for estimating noise properties from the time ordered data, techniques for manipulating the time ordered data, and a number of variants of the maximum likelihood map-making procedure. We pay particular attention to issues pertinent to real CMB data, and present ways of incorporating them within the framework of maximum likelihood map-making. Making a map of the sky is shown to be not only an intermediate step rendering an image of the sky, but also an important diagnostic stage, when tests for and/or removal of systematic effects can efficiently be performed. The case under study is the MAXIMA data set. However, the methods discussed are expected to be applicable to the analysis of other current and forthcoming CMB experiments., Replaced to match the published version, only minor changes

This review discusses the use of molecular modeling tools, together with existing experimental findings, to provide a complete atomic-level description of enzyme dynamics and function. We focus on functionally relevant conformational dynamics of enzymes and the protonation states of substrates. The conformational fluctuations of enzymes usually play a crucial role in substrate recognition and catalysis. Protein dynamics can be altered by a tiny change in a molecular system such as different protonation states of various intermediates or by a significant perturbation such as a ligand association. Here we review recent advances in applying atomistic molecular dynamics (MD) simulations to investigate allosteric and network regulation of tryptophan synthase (TRPS) and protonation states of its intermediates and catalysis. In addition, we review studies using quantum mechanics/molecular mechanics (QM/MM) methods to investigate the protonation states of catalytic residues of β-Ketoacyl ACP synthase I (KasA). We also discuss modeling of large-scale protein motions for HIV-1 protease with coarse-grained Brownian dynamics (BD) simulations.

Objective Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease with significant immune system aberrations resulting from complex heritable genetics as well as environmental factors. We undertook to study the role of TRAF6 as a candidate gene for SLE, since it plays a major role in several signaling pathways that are important for immunity and organ development. Methods Fifteen single-nucleotide polymorphisms (SNPs) across TRAF6 were evaluated in 7,490 SLE patients and 6,780 control subjects from different ancestries. Population-based case-control association analyses and meta-analyses were performed. P values, false discovery rate q values, and odds ratios (ORs) with 95% confidence intervals (95% CIs) were calculated. Results Evidence of associations was detected in multiple SNPs. The best overall P values were obtained for SNPs rs5030437 and rs4755453 (P = 7.85 × 10 -5 and P = 4.73 × 10 -5, respectively) without significant heterogeneity among populations (P = 0.67 and P = 0.50, respectively, in Q statistic). In addition, SNP rs540386, which was previously reported to be associated with rheumatoid arthritis (RA), was found to be in linkage disequilibrium with these 2 SNPs (r 2 = 0.95) and demonstrated evidence of association with SLE in the same direction (meta-analysis P = 9.15 × 10 -4, OR 0.89 [95% CI 0.83-0.95]). The presence of thrombocytopenia improved the overall results in different populations (meta-analysis P = 1.99 × 10 -6, OR 0.57 [95% CI 0.45-0.72], for rs5030470). Finally, evidence of family-based association in 34 African American pedigrees with the presence of thrombocytopenia was detected in 1 available SNP (rs5030437) with a Z score magnitude of 2.28 (P = 0.02) under a dominant model. Conclusion Our data indicate the presence of association of TRAF6 with SLE, consistent with the previous report of association with RA. These data provide further support for the involvement of TRAF6 in the pathogenesis of autoimmunity. Copyright © 2012 by the American College of Rheumatology.

Plantings of Scots pine (Pinus sylvestris L.) on a waste burial site in the Chernobyl Red Forest was shown to greatly influence the long term redistribution of radioactivity contained in sub-surfaces trenches. After 15 years of growth, aboveground biomass of the average tree growing on waste trench no.22 had accumulated 1.7 times more 137Cs than that of trees growing off the trench, and 5.4 times more 90Sr. At the scale of the trench and according to an average tree density of 3300 trees/ha for the study zone, tree contamination would correspond to 0.024% of the 137Cs and 2.52% of the 90Sr contained in the buried waste material. A quantitative description of the radionuclide cycling showed a potential for trees to annually extract up to 0.82% of the 90Sr pool in the trench and 0.0038% of the 137Cs. A preferential 90Sr uptake from the deep soil is envisioned while pine roots would take up 137Cs mostly from less contaminated shallow soil layers. The current upward flux of 90Sr through vegetation appeared at least equal to downward loss in waste material leaching as reported by Dewiere et al. (2004, Journal of Environmental Radioactivity 74, 139-150). Using a prospective calculation model, we estimated that maximum 90Sr cycling can be expected to occur at 40 years post-planting, resulting in 12% of the current 90Sr content in the trench transferred to surface soils through biomass turnover and 7% stored in tree biomass. These results are preliminary, although based on accurate methodology. A more integrated ecosystem study leading to the coupling between biological and geochemical models of radionuclide cycling within the Red Forest seems opportune. Such a study would help in the adequate management of that new forest and the waste trenches upon which they reside. © 2009 Elsevier Ltd. All rights reserved.

Mechanical interplay between the adjacent ventricles is one of the principal modulators of physiopathological heart function, and the underlying mechanisms of interaction are only partially understood, hence hampering clinically useful interpretation of imaging data. In order to characterize the influence of chamber geometry on ventricular coupling, the ventricles and septum are modeled as portions of ellipsoidal shells, and configuration is derived as a function of pressure gradients by combining shell element equilibrium equations through static boundary conditions applied at the sulcus. Diastolic volume (v) surfaces are calculated as a function of pressure (p), contralateral pressure (clp) and intrathoracic pressure (p ( t )) and match literature data where available. Ventricular interaction is characterized in terms of partial derivatives in v-p-clp-p ( t ) space both under physiological and altered (selectively stiffened walls) conditions. The model allows prediction of diastolic ventricular v-p-clp-p ( t ) interplay in a variety of physiopathological circumstances.

We assessed the relationship between tonsillectomy and being a habitual or severe snorer. Volunteers were asked to provide their age and sex, a detailed snoring history covering the frequency and intensity of snoring, and their smoking and alcohol intake habits. After oral and nasal examinations, the tonsil size scores, Mallampati index scores, and nasal obstructions of the volunteers were recorded. Body heights and weights were measured, and body mass indexes were calculated. Being male, aging, an increase in body mass index and tonsillectomy were identified as independent risk factors for being a habitual and severe snorer. Although a nasal obstruction was found to be an independent risk factor for being a habitual snorer, an obstructive tongue base was identified as an independent risk factor for being a severe snorer. Tonsillectomy reduces the risk of being both a habitual and severe snorer. This reduced incidence and intensity of snoring following tonsillectomy could be accepted as a long-term beneficial side effect of the operation. © 2008 Springer-Verlag.

4-Phenyl-N-(β-D-glucopyranosyl)-1H-1,2,3-triazole-1-acetamide (glucosyltriazolylacetamide) has been studied in kinetic and crystallographic experiments with glycogen phosphorylase b (GPb), in an effort to utilize its potential as a lead for the design of potent antihyperglycaemic agents. Docking and molecular dynamics (MD) calculations have been used to monitor more closely the binding modes in operation and compare the results with experiment. Kinetic experiments in the direction of glycogen synthesis showed that glucosyltriazolylacetamide is a better inhibitor (Ki = 0.18 mM) than the parent compound α-D-glucose (Ki = 1.7 mM) or β-D-glucose (Ki = 7.4 mM) but less potent inhibitor than the lead compound N-acetyl-β-D-glucopyranosylamine (Ki = 32 μM). To elucidate the molecular basis underlying the inhibition of the newly identified compound, we determined the structure of GPb in complex with glucosyltriazolylacetamide at 100 K to 1.88 Å resolution, and the structure of the compound in the free form. Glucosyltriazolylacetamide is accommodated in the catalytic site of the enzyme and the glucopyranose interacts in a manner similar to that observed in the GPb-α-D-glucose complex, while the substituent group in the β-posi tion of the C1 atom makes additional hydrogen bonding and van der Waals interactions to the protein. A bifurcated donor type hydrogen bonding involving O3H, N3, and N4 is seen as an important structural motif strengthening the binding of glucosyltriazolylacetamide with GP which necessitated change in the torsion about C8-N2 bond by about 62° going from its free to the complex form with GPb. On binding to GP, glucosyltriazolylacetamide induces significant conformational changes in the vicinity of this site. Specifically, the 280s loop (residues 282-288) shifts 0.7 to 3.1 Å (CA atoms) to accommodate glucosyltriazolylacetamide. These conformational changes do not lead to increased contacts between the inhibitor and the protein that would improve ligand binding compared with the lead compound. In the molecular modeling calculations, the GOLD docking runs with and without the crystallographic ordered cavity waters using the GoldScore scoring function, and without cavity waters using the ChemScore scoring function successfully reproduced the crystallographic binding conformation. However, the GLIDE docking calculations both with (GLIDE XP) and without (GLIDE SP and XP) the cavity water molecules were, impressively, further able to accurately reproduce the finer details of the GPb-glucosyltriazolylacetamide complex structure. The importance of cavity waters in flexible receptor MD calculations compared to "rigid" (docking) is analyzed and highlighted, while in the MD itself very little conformational flexibility of the glucosyltriazolylacetamide ligand was observed over the time scale of the simulations. © 2007 Wiley-Liss, Inc. 71 3 1307 1323 Cited By :27

Eight isomeric networks based on equimolar terpolymers were synthesized using group transfer polymerization (GTP) and were characterized in terms of their swelling properties. Two hydrophilic monomers, the nonionic methoxy hexa(ethylene glycol) methacrylate (HEGMA) and the ionizable 2-(dimethylamino)ethyl methacrylate (DMAEMA), and a hydrophobic (nonionic) monomer, methyl methacrylate (MMA), were employed for the syntheses. 1,4-Bis(methoxytrimethylsiloxymethylene)cyclohexane (MTSMC) was used as the bifunctional GTP initiator, while ethylene glycol dimethacrylate (EGDMA) served as the cross-linker. Seven of the networks were model networks, six of which were based on the symmetrical pentablock terpolymers ABCBA, ACBCA, BACAB, BCACB, CBABC, and CABAC, whereas the seventh model network was based on the statistical terpolymer. The eighth network was a randomly cross-linked network based on the statistical terpolymer, prepared by the simultaneous quaterpolymerization of the three monomers and the cross-linker. The molecular weights and molecular weight distributions of the linear pentablock terpolymer precursors, as well as those of their homopolymer and ABA triblock copolymer precursors, were characterized by gel permeation chromatography (GPC in tetrahydrofuran. The sol fraction of each network was measured and found to be relatively low. The aqueous degrees of swelling of all networks were found to increase at acidic pH due to the ionization of the DMAEMA tertiary amine units. The acidic degrees of swelling of the pentablock terpolymer networks were lower than those of their statistical counterparts due to microphase separation in the former type of networks, also confirmed by thermodynamic calculations and small-angle neutron scattering experiments. © 2007 American Chemical Society. 8 5 1615 1623 Cited By :33

Contains fulltext : 53153.pdf (Publisher’s version ) (Closed access) BACKGROUND: Nurses and other hospital workers are exposed to antineoplastic drugs during daily activities. Previous studies suggest that antineoplastic drugs at occupational exposure levels may be toxic to reproduction, but these studies are not consistent or conclusive. METHODS: Self-administered questionnaires were completed by 4393 exposed and nonexposed nurses employed between 1990 and 1997 (79% response). Questions were asked about pregnancy outcome, work-related exposures, and lifestyle. Exposure to antineoplastic drugs was estimated using task-based dermal exposure measurements and self-reported task frequencies. Time to pregnancy was modeled using survival analysis, and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for other reproductive outcomes using multiple logistic regression analysis. Associations were further explored by nonparametric regression modeling. RESULTS: Nurses highly exposed to antineoplastic drugs took longer to conceive than referent nurses (adjusted hazard ratio = 0.8; CI = 0.6-0.9). Exposure to antineoplastic drugs was associated with premature delivery (OR per unit increase in ln[exposure] = 1.08; CI = 1.00-1.17) and low birth weight (OR per unit increase in ln[exposure] = 1.11; 1.01-1.21). Penalized smoothed spline plots corroborated these log-linear relations. Spontaneous abortion, stillbirth, congenital anomalies, and sex of offspring appeared not to be related to exposure to antineoplastic drugs. CONCLUSION: Antineoplastic drugs may reduce fertility and increase poor neonatal outcomes among occupationally exposed oncology nurses.

We consider a computing system where a master processor assigns a task for execution to worker processors that may collude. We model the workers' decision of whether to comply (compute the task) or not (return a bogus result to save the computation cost) as a game among workers. That is, we assume that workers are rational in a game-theoretic sense. We identify analytically the parameter conditions for a unique Nash Equilibrium where the master obtains the correct result. We also evaluate experimentally mixed equilibria aiming to attain better reliability-profit trade-offs. For a wide range of parameter values that may be used in practice, our simulations show that, in fact, both master and workers are better off using a pure equilibrium where no worker cheats, even under collusion, and even for colluding behaviors that involve deviating from the game. © 2015 Fernández Anta et al. 10 3 Cited By :1

The inverse method is a numerical method for fast estimation of adsorption isotherm parameters directly from a few overloaded elution profiles and it was recently extended to adsorption isotherm acquisition in gradient elution conditions. However, the inverse method in gradient elution is cumbersome due to the complex adsorption isotherm models found in gradient elution. In this case, physicochemically correct adsorption models have very long calculation times. The aim of this study is to investigate the possibility of using a less complex adsorption isotherm model, with fewer adjustable parameters, but with preserved/acceptable predictive abilities. We found that equal or better agreement between experimental and predicted elution profiles could be achieved with less complex models. By being able to select a model with fewer adjustable parameters, the calculation times can be reduced by at least a factor of 10.

OBJECTIVE: To assess the age at menopause (AM) in Latin America urban areas. DESIGN: A total of 17,150 healthy women, aged 40 to 59 years, accompanying patients to healthcare centers in 47 cities of 15 Latin American countries, were surveyed regarding their age, educational level, healthcare coverage, history of gynecological surgery, smoking habit, presence of menses, and the use of contraception or hormone therapy at menopause. The AM was calculated using logit analysis. RESULTS: The mean age of the entire sample was 49.4 ± 5.5 years. Mean educational level was 9.9 ± 4.5 years, and the use of hormone therapy and oral contraception was 22.1% and 7.9%, respectively. The median AM of women in all centers was 48.6 years, ranging from 43.8 years in Asuncion (Paraguay) to 53 years in Cartagena de Indias (Colombia). Logistic regression analysis determined that women aged 49 living in cities at 2,000 meters or more above sea level (OR = 2.0, 95% CI: 1.4-2.9, P less than 0.001) and those with lower educational level (OR = 1.9, 95% CI: 1.3-2.8, P less than 0.001) or living in countries with low gross national product (OR = 2.1, 95% CI: 1.5-2.9, P less than 0.001) were more prone to an earlier onset of menopause. CONCLUSIONS: The AM varies widely in Latin America. Lower income and related poverty conditions influence the onset of menopause. © 2006 by The North American Menopause Society.

Background: Reduced heart rate recovery (HRR) in coronary artery disease (CAD) is predictive of increased cardiovascular mortality and is related to reduced parasympathetic tonus. Objective: To investigate HRR and heart rate variability (HRV) measured at steady state condition and the relationship between these two parameters in CAD. Materials and Methods: In our study, we enrolled 33 (28 males, mean age 52.4 ± 9.6 years) patients with CAD who did not have heart failure, atrial fibrillation, pacemaker, and any disease state that could affect the autonomic functions and 38 age-matched healthy subjects (21 males, mean age 48.3 ± 7.8 years). All the patients underwent submaximal treadmill exercise testing (Bruce protocol). HRR was calculated by subtracting the heart rate values at the 1st, 2nd, and 3rd minutes of the recovery phase from the peak heart rate (HRR1, HRR 2, HRR3). Before exercise testing, short-term steady state HRV analyses of all subjects were obtained with the time- and frequency-domain methods and were correlated to HRR. For frequency-domain analysis, low-frequency HRV (LF, 0.004-0.15 Hz), high-frequency HRV (HF, 0.15-0.5 Hz), and LF/HF ratio were measured for 5 minutes in the morning. For time-domain analysis, standard deviation of the normal-to-normal NN intervals (SDNN), square root of the mean squared differences of successive N-N intervals (RMSSD), and proportion derived by dividing the number of interval differences of successive N-N intervals greater than 50 ms by the total number of N-N intervals (pNN50) were obtained. Only HRR3 was used for the correlation analysis. Results: In CAD groups, the HF, an indicator of parasympathetic activation, was significantly reduced, whereas the LF and LF/HF values, which are indicators of sympathetic activity, were increased (P = 0.0001 for each parameter). The time-domain parameters SDNN, RMSSD, and pNN50 were significantly reduced in the patient group (P = 0.0001, P = 0.009, and P = 0.0001, respectively). Similar to the HRV parameters, the HRR1, HRR2, and HRR3 values were significantly reduced in the patient group (P = 0.0001 for each parameter). We observed a significant negative correlation between HRR3 and LF (r =-0.67, P = 0.0001) and between HRR3 and LF/HF (r =-0.62, P < 0.0001), while there was a significant positive correlation between HRR 3 and HF, SDNN, RMSSD, and pNN50 (r = 0.69, P = 0.0001; r = 0.41, P = 0.0001; r = 0.31, P = 0.008; and r = 0.44, P = 0.0001). Conclusions: HRR and HRV are significantly reduced in CAD. The reduction in HRR is parallel to the changes in HRV parameters. HRR, which can be measured easily in the recovery phase of exercise testing, can be used to detect the depression of parasympathetic tonus and to evaluate the basal autonomic balance in this patient group. ©2006, Copyright the Authors.

Primary objective: The purpose of this study was to assess the relationship between sex and traumatic brain injury (TBI) mortality.Methods and procedures: A total of 20 465 persons with TBI were identified from a Colorado population-based surveillance system for 1994–1998. Case fatality ratios were calculated to identify sex differences for selected risk factors. Unconditional logistic regression was used to determine the relationship between TBI mortality and sex controlling for risk factors.Main outcomes and results: Adjusting for age, race, metropolitan residence and penetrating injury, the estimated odds of TBI mortality for males compared to females was 1.21 (95% CI 1.10, 1.34) for pre-hospital fatalities and 1.19 (95% CI 1.05, 1.37) for hospital fatalities.Conclusion: Results indicate differences in TBI mortality comparing males and females. Future studies are warranted to identify if behaviour and physiological responses are associated with TBI outcomes among males and females.

Various paeonol analogues were synthesized and tested in vitro as inhibitors of platelet aggregation. Structural properties (or descriptors) of paeonol analogues were calculated and the structure-activity relationships were determined. Several multiple linear and nonlinear regression models and back-propagation neural network model were tested and the latter using relative positive charge, hydration energy, and hydrophilic factor as inputs gave the best data fitting with R2 = 0.89 and qpre2=0.66. The correlation coefficient between antiplatelet inhibition activity with an interaction energy between the paeonol compounds with COX-1 enzyme is only 0.39. ? 2005 Elsevier Ltd. All rights reserved.

This study investigates the release mechanism of a hydrophilic drug (caffeine) from hydrophobic matrix tablets composed of starch acetate. Different particle size fractions of starch acetate were mixed with caffeine (22% V/V) to obtain various mixture organisations in the powder, as 14 well as in the final tablet. The organisation of powder mixtures was calculated by the carrier payload of starch acetate particles, while the pore size distributions in tablets were measured by mercury intrusion porosimetry. A carrier payload below I indicated the existence of a free starch acetate particle surface, while numbers greater than 1 pointed to a complete occupation of the starch acetate particle surface area by caffeine particles. The carrier payload calculations gave a good prediction for the existence of a starch acetate matrix in the tablet structures. Caffeine matrices in tablets compressed from the mixtures could be detected by mercury intrusion porosimetry measurements. The existence of different matrices, as well as different pore networks, determined the physical changes of the tablets and the release mechanism of caffeine during dissolution tests. When a tablet contained only a caffeine matrix, rapid tablet disintegration and immediate release of the total amount of caffeine occurred. A single matrix of starch acetate resulted in tablets that remained intact, although cracks were formed. The co-existence of matrices of both materials created surface erosion of the tablet. The caffeine release profiles of tablets that remained intact or showed erosion were fitted by an equation containing both diffusional and relaxational factors to describe the effect of tablet porosity on drug release. (c) 2005 Elsevier B.V. All rights reserved.

Computations find that o-phenylene(halo)carbenonitrenes 2-XN, X = F, Cl, Br, have quinoidal singlet biradical ground states such as the parent o-phenylenecarbenonitrene (2-HN). Compared to the parent 2-HN, halogen substitution stabilizes the A″ states relative to the A′ ones. Halogen substitution also affects the barrier and exothermicity of the ring-opening reaction (to form unsaturated nitriles 4-XN, X = F, Cl, Br), but it has a smaller effect on the ring-closing reaction (to form benzo(aza) cyclobutadiene 3-XN, X = F, Cl, Br). Attempts to generate and observe the o-phenylene(halo)carbenonitrenes 2-XN, X = F, Cl, Br, using matrix isolation spectroscopy under conditions similar to those of the successful observation of 2-HN failed. Instead, the observed photoproducts were a mixture of 3-XN and 4-XN. In each case, the major product of the mixture appears to be the thermodynamically more stable one. In the case of X = Br, the observed mixture contains an additional component that is postulated to be Z-6-BrN. o-Phenylenechlorocarbenocarbene is also computed to have a quinoidal singlet biradical ground state and relatively stabilized A″ excited states. Attempts to generate the biscarbene under matrix isolation conditions led to the detection of benzochlorocyclobutadiene (3-ClC), small amounts of the ring-open product (dienediyne 4-ClC), and cycloalkyne 5-ClC. Computations suggest that the formation of 5-ClC implies the generation of Z-6-ClC, which is analogous to the formation of Z-6-BrN from 2-BrN. © 2005 American Chemical Society. 70 19 7744 7754 Cited By :9

In this study, a geometric and experimental work of the urinary bladder of a dog is presented. Experimentally, the diameters on the neck (collum vesicae region), the body (corpus vesicae region), the bottom (apex region) and the longitudinal length of the urinary bladder were measured. Geometrically it was shown that the urinary bladder is comparable with a surface of revolution of a planar (profile) curve. On the same regions of the modelled surface the diameters of the horizontal sections have been measured. It was found that the geometric and the experimental values were closely related. Further the Gaussian curvature K at certain points on the same regions of the modelled surface was calculated. The quadratic approximations of the urinary bladder surface was described with the sign of K at those points.

In diabetic neuropathic subjects, the hardness of foot sole soft tissue increases, and its thickness reduces, in different foot sole areas. Finite element analysis (FEA) of a three-dimensional two-arch model of the foot was performed to evaluate the effect of foot sole stresses on plantar ulcer development. Three sets of foot sole soft-tissue properties, i.e. isotropic (with control hardness value), diabetic isotropic (with higher hardness value) and anisotropic diabetic conditions, were simulated in the push-off phase, with decreasing foot sole soft-tissue thicknesses in the forefoot region, and the corresponding stresses were calculated. The results of the stress analyses for diabetic subject (anisotropic) foot models showed that with non-uniformly increased hardness and decreased foot sole soft-tissue thickness, the normal and shear stresses at the foot sole increased (compared with control values) by 52.6% and 53.4%, respectively. Stress analyses also showed high ratios of gradients of normal and shear stresses of the order of 6.6 and 3.3 times the control values on the surface of the foot sole, and high relative values of stress gradients for normal and shear stresses of 6.25 and 4.35 times control values respectively, between the foot sole surface and the adjacent inner layer of the foot sole, around a particular region of the foot sole with anisotropic properties. These ratios of high gradients and relative gradients of stresses due to changes in soft-tissue properties may be responsible for the development of plantar ulcers in diabetic neuropathic feet. ? IFMBE: 2004.

Background: Coronary flow reserve (CFR) and fractional flow reserve (FFR) provide complementary information on the coronary circulation. Using a pressure wire, it is possible to calculate CFR by thermodilution (CFRthermo), so that FFR and CFR can be measured with a single guide wire. The present multicentric study was performed to compare the feasibility of CFR thermo obtained with an improved algorithm and a standardized injection technique and its agreement with Doppler-derived CFR (CFR Doppler). Methods and results: In 86 patients with coronary artery disease recruited during 1 week in eight centres FFR, CFRthermo and CFRDoppler were measured. FFR could be obtained in all patients (100%). An optimal CFRDoppler could be obtained in 69% of the patients. CFRthermo could be obtained in 97% of the patients. A significant correlation was found between CFRDoppler and CFR thermo (r=0.79, Pthermo tended to be higher than CFRDoppler. Conclusions: In a setting close to 'real world' practice, this multicentric study confirms the feasibility and reliability of thermodilution-derived CFR. In addition, the safety and the swiftness of assessing FFR and CFR with one single guide wire makes the latter a unique clinical tool for the evaluation of the coronary circulation.

A comprehensive study was conducted to determine thorium, uranium and potassium elemental concentrations in surface soils throughout the accessible area of Cyprus using high-resolution gamma-ray spectrometry. A total of 115 soil samples was collected from all over the bedrock surface of the island based on the different lithological units of the study area. The soil samples were sieved through a fine mesh, sealed in 1000-mL plastic Marinelli beakers, and measured in the laboratory in terms of their gamma radioactivity for a counting time of 18 hours each. From the measured gamma-ray spectra, elemental concentrations were determined for thorium (range from 2.5x10^-3 to 9.8 micro g g-1), uranium (from 8.1x10^-4 to 3.2 micro g g-1) and potassium (from 1.3x10^-4 to 1.9 %). The Arithmetic mean values (A.M. +- S.D.) calculated are (1.2 +- 1.7) micro g g-1, (0.6 +- 0.7) micro g g-1, and (0.4 +- 0.3) %, for thorium, uranium and potassium, respectively, which are by a factor of three to six lower than the world average values of 7.4 micro g g-1 (Th), 2.8 micro g g-1 (U) and 1.3 % (K) derived from all data available worldwide. The best-fitting relation between the concentrations of Th and K versus U, and also of K versus Th, is essentially of linear type with a correlation coefficient of 0.93, 0.84, and 0.90, respectively. The Th/U, K/U, and K/Th ratios (slopes) calculated are equal to 2.0, 2.8x10^3,and 1.4x10^3, respectively., Comment: 24 pages including 3 tables and 4 figures; minor changes; accepted by J. of Environmental Radioactivity

We discuss the production of two hadrons in e+e- annihilation within the framework of perturbative QCD. The cross section for this process is calculated to next-to-leading order accuracy with a selection of variables that allows the consideration of events where the two hadrons are detected in the same jet. In this configuration we contemplate the possibility that the hadrons come from a double fragmentation of a single parton. The double-fragmentation functions required to describe the transition of a parton to two hadrons are also necessary to completely factorize all collinear singularities. We explicitly show that factorization applies to next-to-leading order in the case of two-hadron production., 13 pages, 4 figures