88 research outputs found

    Electrochemical performance of plant trace element incorporated silver nanoparticles synthesis from Datura metel L.

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    In our report, silver nanoparticles (AgNPs) were prepared from the leaf extract of Datura metel L. via the green synthesis method. Datura metel L. is a herbal medicinal plant from the Solanaceae family. The as‐prepared AgNPs were characterized using UV‐Vis spectrometer, X‐ray Diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM) with Energy Dispersive X‐ray (EDAX) analysis. The peak appearance of a Surface Plasmon Resonance (SPR) at 415 nm suggested the creation of AgNPs in the UV‐Vis spectrum. The XRD pattern showed the face‐centered cubic crystal structure of AgNPs with organometallic complex phase. Based on the FTIR spectrum, the peaks revealed the existence of biomolecules. SEM images showed the shape of the clastic rocks and the EDAX profile authenticated the presence of Ag and plant trace element. The cyclic voltammetry, Chronopotentiometry, and electrochemical impedance spectroscopy analysis were performed on an as‐prepared Ag electrode. A specific capacitance of 267.59 F/g at 0.5 A/g and a cyclic retention of 83.7% after 5000 charge‐discharge cycles were obtained. Hence, this material could be utilized in supercapacitor energy storage devices

    Online chemical modeling environment (OCHEM): web platform for data storage, model development and publishing of chemical information

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    The Online Chemical Modeling Environment is a web-based platform that aims to automate and simplify the typical steps required for QSAR modeling. The platform consists of two major subsystems: the database of experimental measurements and the modeling framework. A user-contributed database contains a set of tools for easy input, search and modification of thousands of records. The OCHEM database is based on the wiki principle and focuses primarily on the quality and verifiability of the data. The database is tightly integrated with the modeling framework, which supports all the steps required to create a predictive model: data search, calculation and selection of a vast variety of molecular descriptors, application of machine learning methods, validation, analysis of the model and assessment of the applicability domain. As compared to other similar systems, OCHEM is not intended to re-implement the existing tools or models but rather to invite the original authors to contribute their results, make them publicly available, share them with other users and to become members of the growing research community. Our intention is to make OCHEM a widely used platform to perform the QSPR/QSAR studies online and share it with other users on the Web. The ultimate goal of OCHEM is collecting all possible chemoinformatics tools within one simple, reliable and user-friendly resource. The OCHEM is free for web users and it is available online at http://www.ochem.eu

    Multiwavelength behaviour of the blazar OJ 248 from radio to Îł-rays

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    We present an analysis of the multiwavelength behaviour of the blazar OJ 248 at z = 0.939 in the period 2006-2013. We use low-energy data (optical, near-infrared, and radio) obtained by 21 observatories participating in the Gamma-Ray Large Area Space Telescope (GLAST)-AGILE Support Program of the Whole Earth Blazar Telescope, as well as data from the Swift (optical-UV and X-rays) and Fermi (Îł-rays) satellites, to study flux and spectral variability and correlations among emissions in different bands. We take into account the effect of absorption by the Damped Lyman α intervening system at z = 0.525. Two major outbursts were observed in 2006-2007 and in 2012-2013 at optical and near-IR wavelengths, while in the high-frequency radio light curves prominent radio outbursts are visible peaking at the end of 2010 and beginning of 2013, revealing a complex radio-optical correlation. Cross-correlation analysis suggests a delay of the optical variations after the Îł-ray ones of about a month, which is a peculiar behaviour in blazars. We also analyse optical polarimetric and spectroscopic data. The average polarization percentage P is less than 3 per cent, but it reaches ∌19 per cent during the early stage of the 2012-2013 outburst. A vague correlation of P with brightness is observed. There is no preferred electric vector polarization angle and during the outburst the linear polarization vector shows wide rotations in both directions, suggesting a complex behaviour/structure of the jet and possible turbulence. The analysis of 140 optical spectra acquired at the Steward Observatory reveals a strong Mg II broad emission line with an essentially stable flux of 6.2 × 10- 15 erg cm- 2 s- 1 and a full width at half-maximum of 2053 km s- 1

    VizieR Online Data Catalog: Mrk 421 multi-wavelength variability, 2007-2009 (Ahnen+, 2016)

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    Data of Mrk 421 are presented for the following instruments and bands from radio to very high energy gamma-rays: Metsahovi (37GHz), OVRO (15GHz), GASP (R band), RXTE/ASM (2-10keV), Swift/BAT(15-50keV), MAGIC (>400 GeV). The observation period is from 10th February 2007 (MJD 54141) to 23rd July 2009 (MJD 55035). Figure 2 includes the light curves of the above mentioned instruments. Figure 3 and 4 show the fractional variability F_var for these light curves of the above mentioned light curves for the whole time span (Fig. 3) and for the separate time spans P1, P2, P3 (Fig. 4). (3 data files). <P /

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

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    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

    The Complementarity Principle—One More Step towards Analytical Docking on the Example of Dihydrofolate Reductase Complexes

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    New approaches to assessing the “enzyme–ligand” complementarity, taking into account hydrogens, have been proposed. The approaches are based on the calculation of three-dimensional maps of the electron density of the receptor–ligand complexes. The action of complementarity factors, first proposed in this article, has been demonstrated on complexes of human dihydrofolate reductase (DHFR) with ligands. We found that high complementarity is ensured by the formation of the most effective intermolecular contacts, which are provided due to predominantly paired atomic–atomic interactions, while interactions of the bifurcate and more disoriented type are minimized. An analytical docking algorithm based on the proposed receptor–ligand complementarity factors is proposed
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