bluuebunny/crossref_metadata_2025_split huggingface dataset:
Critically Evaluated Rate Coefficients in Radical Polymerization – 8. Propagation Rate Coefficients for Vinyl Acetate in Bulk
Authors: Barner‐Kowollik Christopher , Beuermann Sabine , Buback Michael , Hutchinson Robin A. , Junkers Tanja , Kattner Hendrik , Manders Bart , Nikitin Anatoly N. , Russell Gregory T. , van Herk Alex M. 
Published: September 2016

Propagation rate coefficient values, kp, reported by several groups for radical polymerization of bulk vinyl acetate are critically evaluated. All data are obtained by the combination of pulsed‐laser polymerization and subsequent polymer analysis by size exclusion chromatography, as recommended by the IUPAC Working Party on Modeling of Polymerization Kinetics and Processes. Although a small (≈15%) increase in kp is observed as laser pulse repetition rate is increased from low (25–100 Hz) to high (300–500 Hz) values, all of the data fulfill the required consistency criteria and thus are combined into a benchmark set covering the temperature range of 5–70 °C. The data are fitted well by an Arrhenius relation resulting in a pre‐exponential factor of 1.35 × 107 L mol−1 s−1 and an activation energy of 20.4 kJ mol−1, with 95% confidence ellipsoids for the parameters also presented.
image
Very High Solid State Photoluminescence Quantum Yields of Poly(tetraphenylethylene) Derivatives
Authors: Baysec Sebnem , Preis Eduard , Allard Sybille , Scherf Ullrich 
Published: September 2016

Five different poly(arylene‐diarylvinylene)s have been synthesized by reductive polyolefination starting from the corresponding bis(α,α‐dichlorobenzyl)‐substituted monomers and dicobaltoctacarbonyl as reducing agent. The resulting polymers all contain main chain tetraphenylethylene units. Thanks to the aggregation‐induced emission effect, the corresponding polymer films show remarkably high photoluminescence quantum yields (PLQYs) of 32%–73%. The polymer with the highest PLQY is tested as solid state sensing material for the PL‐quenching‐based detection of nitroaromatic analytes (1,3,5‐trinitrobenzene as prototypical analyte).image
Nanoparticle Translocation through Conical Nanopores: A Finite Element Study of Electrokinetic Transport
Authors: Rempfer Georg , Ehrhardt Sascha , Holm Christian , de Graaf Joost 
Published: September 2016

Recent years have seen a surge of interest in nanopores because such structures show a strong potential for characterizing macromolecules, e.g., DNA. Here, the authors theoretically investigate the translocation of a spherical nanoparticle through a conical nanocapillary, by numerically solving the coupled system of electrokinetic continuum equations. Based on their findings, the authors formulate simple guidelines for obtaining the maximum current signal during the translocation event, which should be transferable to other nanopore geometries. In addition, the dependence of the signal strength on particle properties, such as surface charge and size, is evaluated. Finally, the authors identify conditions under which the translocation is prevented by the formation of a strong electroosmotic barrier and show that the particle may even become trapped at the pore orifice, without imposing an external hydrostatic pressure difference.
image
Diffusion in hierarchical systems: A simulation study in models of healthy and diseased muscle tissue
Authors: Hall Matt G. , Clark Chris A. 
Published: September 2016

PurposeTo investigate the sensitivity of diffusion‐MR signal to microstructural change in muscle tissue associated with pathology, and recommend optimal acquisition parameters.MethodsWe employ Monte‐Carlo simulation of diffusing spins in hierarchical tissue to generate synthetic diffusion‐weighted signal curves over a wide range of scan parameters. Curves are analyzed using entropy—a measure of curve complexity. Entropy change between a baseline and various microstructural scenarios is investigated. We find acquisitions that optimize entropy difference in each scenario.ResultsPermeability changes have a large effect on the diffusion‐weighted signal curve. Muscle fiber atrophy is also important, although differentiating between mechanisms is challenging. Several acquisitions over a range of diffusion times is optimal for imaging microstructural change in muscle tissue. Sensitivity to permeability is optimized for high gradient strengths, but sensitivity to other scenarios is optimal at other values.ConclusionsThe diffusion‐attenuated signal is sensitive to the microstructural changes, but the changes are subtle. Taking full advantage of the changes to the overall curve requires a set of acquisitions over a range of diffusion times. Permeability causes the largest changes, but even the very subtle changes associated with fiber radius distribution change the curves more than noise alone. Magn Reson Med 78:1187–1198, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial‐NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non‐commercial and no modifications or adaptations are made.
Chemotherapeutic treatment reduces circulating levels of surfactant protein‐D in children with acute lymphoblastic leukemia
Authors: Rathe Mathias , Sorensen Grith L. , Wehner Peder S. , Holmskov Uffe , Sangild Per T. , Schmiegelow Kjeld , Müller Klaus , Husby Steffen 
Published: September 2016

AbstractBackgroundSurfactant protein D (SP‐D) is a host defense molecule of the innate immune system that enhances pathogen clearance and modulates inflammatory responses. We hypothesized that circulating SP‐D levels are associated with chemotherapy‐induced mucositis and infectious morbidity in children with acute lymphoblastic leukemia (ALL).ProcedureIn a prospective study, 43 children receiving treatment for ALL were monitored for mucosal toxicity from diagnosis through the induction phase of treatment. Serial blood draws were taken to determine the levels of SP‐D, interleukin‐6 (IL‐6), C‐reactive protein, and white blood cells. Data on fever, antibiotics, and bacteremia were collected. Baseline levels of circulating SP‐D were compared with healthy controls.ResultsBaseline values of circulating SP‐D were similar to levels in healthy controls (median: 829 ng/ml vs. 657 ng/ml, respectively, P > 0.05). After initiation of chemotherapy, a significant reduction in SP‐D levels was observed at all time points: 704 ng/ml at day 8, 413 ng/ml at day 15, 395 ng/ml at day 22, and 520 ng/ml at day 29 (all, P < 0.05). No significant associations between SP‐D values, the occurrence of mucosal toxicity, or infectious morbidity were observed. However, loss of circulating SP‐D from days 8 to 15 was associated with more systemic inflammation, and lower SP‐D values at day 15 were associated with elevated intestinal mucositis scores (P < 0.05).ConclusionsThe current study supports the hypothesis that the detrimental effect of chemotherapy on patients’ immune functions includes decreased circulating levels of innate mucosal molecules such as SP‐D, potentially aggravating mucosal and systemic inflammatory responses.
Degradation and regeneration in mc‐Si after different gettering steps
Authors: Zuschlag Annika , Skorka Daniel , Hahn Giso 
Published: September 2016

AbstractLight and elevated temperature induced degradation (LeTID) affects significantly the performance of multicrystalline (mc) Si passivated emitter and rear cell (PERC) solar cells, and underlying mechanisms of LeTID are still unknown. In this work LeTID and following regeneration of an industrial mc‐Si PERC solar cell is compared to differently processed minority charge carrier lifetime samples under illumination (1 sun) and elevated temperature (75 °C). LeTID on cell level reveals the same kinetics compared to lifetime samples. Varying the processing sequence has a significant effect on LeTID of lifetime samples. Ungettered samples with fired SiNx:H surface passivation show a very strong LeTID and regeneration effect, with degradation kinetics being similar for all wafer areas irrespective of initial material quality. In contrast, regeneration sets in earlier in good quality areas. Differently gettered samples with lower contamination level than ungettered samples are less sensitive to LeTID, while overall degradation and regeneration behavior is strongly influenced by applied gettering sequences. Al‐gettered samples show a more pronounced degradation effect than P‐gettered samples, leading to the assumption that P‐gettering is more effective in the reduction of LeTID sensitive defects. If the gettering step is less effective, in lifetime samples after degradation a beginning regeneration effect could be observed. A model is presented, describing LeTID in boron as well as gallium doped mc‐Si being based on impurities that can be gettered and redistributed during high temperature steps. Using this experimental approach helps to clarify the underlying mechanisms of LeTID and leads to a better understanding of degradation and regeneration mechanisms in mc Si. Copyright © 2016 John Wiley & Sons, Ltd
Preparation and thermal stability of fluoroalkyl end‐capped vinyltrimethoxysilane oligomeric silica/boric acid nanocomposites‐encapsulated a variety of low molecular weight organic compounds
Authors: Aomi Yuta , Nishida Masakazu , Sawada Hideo 
Published: September 2016

ABSTRACTFluoroalkyl end‐capped vinyltrimethoxysilane oligomer [RF‐(VM)n‐RF] reacted with boric acid to afford the corresponding fluorinated oligomeric silica/boric acid nanocomposite [RF‐(VMSiO2)n‐RF/B(OH)3] fine particles with mean diameter: 36–105 nm. The obtained RF‐(VMSiO2)n‐RF/B(OH)3 nanocomposites were applied to the encapsulation of low molecular weight organic compounds such as diphenylsilanediol, 1,1′‐bi‐2‐naphthol, 4,4′‐biphenol, bisphenol A, bisphenol F, bisphenol AF, biphenyl, dibenzyl, and pentaerythritol into these nanocomposite cores to provide the corresponding fluorinated oligomeric silica/boric acid nanocomposites—encapsulated these organic molecules. Interestingly, the obtained nanocomposites were found to exhibit no weight loss behavior corresponding to the contents of these guest molecules even after calcination at 800 °C, although these nanocomposites were isolated through no purification process. The RF‐(VMSiO2)n‐RF nanocomposites—encapsulated these organic guest molecules were prepared under similar conditions. However, it was demonstrated that these nanocomposites can provide the clear weight loss corresponding to the contents of these guest molecules in the nanocomposites after calcination at 800 °C. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 3835–3845
Crucial steps in the structure determination of a coronavirus spike glycoprotein using cryo‐electron microscopy
Authors: Walls Alexandra , Tortorici M. Alejandra , Bosch Berend‐Jan , Frenz Brandon , Rottier Peter J. M. , DiMaio Frank , Rey Felix A. , Veesler David 
Published: September 2016

AbstractThe tremendous pandemic potential of coronaviruses was demonstrated twice in the last 15 years by two global outbreaks of deadly pneumonia. Entry of coronaviruses into cells is mediated by the transmembrane spike glycoprotein S, which forms a trimer carrying receptor‐binding and membrane fusion functions. Despite their biomedical importance, coronavirus S glycoproteins have proven difficult targets for structural characterization, precluding high‐resolution studies of the biologically relevant trimer. Recent technological developments in single particle cryo‐electron microscopy allowed us to determine the first structure of a coronavirus S glycoprotein trimer which provided a framework to understand the mechanisms of viral entry and suggested potential inhibition strategies for this family of viruses. Here, we describe the key factors that enabled this breakthrough.
Modeling oblong proteins and water‐mediated interfaces with RosettaDock in CAPRI rounds 28–35
Authors: Marze Nicholas A. , Jeliazkov Jeliazko R. , Roy Burman Shourya S. , Boyken Scott E. , DiMaio Frank , Gray Jeffrey J. 
Published: September 2016

ABSTRACTThe 28th–35th rounds of the Critical Assessment of PRotein Interactions (CAPRI) served as a practical benchmark for our RosettaDock protein–protein docking protocols, highlighting strengths and weaknesses of the approach. We achieved acceptable or better quality models in three out of 11 targets. For the two α‐repeat protein–green fluorescent protein (αrep–GFP) complexes, we used a novel ellipsoidal partial‐global docking method (Ellipsoidal Dock) to generate models with 2.2 Å/1.5 Å interface RMSD, capturing 49%/42% of the native contacts, for the 7‐/5‐repeat αrep complexes. For the DNase–immunity protein complex, we used a new predictor of hydrogen‐bonding networks, HBNet with Bridging Waters, to place individual water models at the complex interface; models were generated with 1.8 Å interface RMSD and 12% native water contacts recovered. The targets for which RosettaDock failed to create an acceptable model were typically difficult in general, as six had no acceptable models submitted by any CAPRI predictor. The UCH‐L5–RPN13 and UCH‐L5–INO80G de‐ubiquitinating enzyme–inhibitor complexes comprised inhibitors undergoing significant structural changes upon binding, with the partners being highly interwoven in the docked complexes. Our failure to predict the nucleosome‐enzyme complex in Target 95 was largely due to tight constraints we placed on our model based on sparse biochemical data suggesting two specific cross‐interface interactions, preventing the correct structure from being sampled. While RosettaDock's three successes show that it is a state‐of‐the‐art docking method, the difficulties with highly flexible and multi‐domain complexes highlight the need for better flexible docking and domain‐assembly methods. Proteins 2017; 85:479–486. © 2016 Wiley Periodicals, Inc.
Bounded H∞ synchronization for time‐varying networks with probability‐dependent information
Authors: Wang Fan , Liang Jinling 
Published: September 2016

SummaryThis paper addresses the bounded H∞ synchronization problem for the time‐varying coupled networks with stochastic noises and randomly occurring nonlinearities over a finite horizon. The bounded H∞ synchronization performance constraint is proposed to quantify the degree of the synchronization regarding the exogenous disturbances. The nonlinearities considered in this paper are assumed to satisfy the sector‐like conditions and characterized by a time‐varying Bernoulli distribution with measurable probability in real time. Based on the Kronecker product and the Hadamard product, a sufficient condition is established firstly to ensure the bounded H∞ synchronization of the network by utilizing the probability‐dependent method. Then the obtained criterion is further converted into a computationally available one by transforming the time‐varying probability into a polytopic form, which is presented in terms of matrix inequalities and hence can be verified easily by applying the Matlab toolbox. Finally, simulation examples are given to demonstrate the effectiveness of the theoretical results. Copyright © 2016 John Wiley & Sons, Ltd.
Facile Biopolymer Assisted Synthesis of Hollow SnO2 Nanostructures and Their Application in Dye Removal
Authors: Chowdhury Rakesh , Barah Nilotpal , Rashid Md. Harunar 
Published: September 2016

AbstractHerein, we report the synthesis of SnO2 nanostructures by alkaline hydrolysis of the corresponding metal ions in presence of biopolymer additive such as carboxy methylcellulose at 65 °C. X‐ray diffraction studies confirmed the formation of pure crystalline tetragonal SnO2 nanostructures. Microscopic results revealed that addition of biopolymer results in the formation of hollow nanostructures. The sizes of such hollow nanostructures are controllable by varying the concentration of the biopolymer. The hollow nanostructures are further characterized by other spectroscopic techniques such as UV‐vis spectroscopy, photoluminescence spectroscopy, X‐ray photoelectron spectroscopy and energy dispersive X‐ray spectroscopy. These hollow SnO2 nanostructures are porous and show excellent adsorption capability in removal of organic dye, methylene blue from its aqueous solution at room temperature. The recovered SnO2 nanostructures can be reused in successive batches for dye adsorption without much losing its adsorption capacities.
Full Library of (Bis–allyl)‐deuterated Arachidonic Acids: Synthesis and Analytical Verification
Authors: Fomich Maksim A. , Bekish Andrei V. , Vidovic Dragoslav , Lamberson Connor R. , Lysenko Ivan L. , Lawrence Peter , Brenna J. Thomas , Sharko Olga L. , Shmanai Vadim V. , Shchepinov Mikhail S. 
Published: September 2016

AbstractDeuteration at bis‐allylic positions slows down hydrogen abstraction, thereby reducing the rate of polyunsaturated fatty acids (PUFA) oxidation. Arachidonic acid undergoes oxidation through both enzymatic and non‐enzymatic mechanisms, giving rise to a range of important products with variable biological activity, including pro‐ and anti‐inflammatory properties. We report on the synthesis and verification of a full library of arachidonic acids variably deuterated at the bis‐allylic (C7, C10, C13) positions: 7,7‐D2‐arachidonic acid, 10,10‐D2‐arachidonic acid, 13,13‐D2‐arachidonic acid, 7,7,10,10‐D4‐arachidonic acid, 7,7,13,13‐D4‐arachidonic acid, 10,10,13,13‐D4‐arachidonic acid, and 7,7,10,10,13,13‐D6‐arachidonic acid isotopologues. The library is intended to be useful for determining the relative importance of enzymatic versus non‐enzymatic oxidation at particular sites in vivo.
Photochemistry of 5‐Halogenosalicylic Acids: Evidence of the Triplet Involvement in the Carbene Formation
Authors: Tafer Radia , de Sainte‐Claire Pascal , Vicendo Patricia , Boulkamh Abdelaziz , Richard Claire 
Published: September 2016

AbstractThe heterolytic photodehalogenation of 4‐halogenophenols in water is known to yield the long‐lived triplet carbene 4‐oxo‐2,5‐dienylidene. However, the nature of the excited state from which dehalogenation takes place remains an open issue. To get further insight into the mechanism of carbene formation, we investigated the photolysis of 5‐chlorosalicylic acid and 5‐bromosalicylic acid from experimental and theoretical points of view. Our results showed that irradiation of monoanionic species in water leaded to the formation of the carbene species and its characteristic photoproducts. Moreover, triplet excited states could be detected by laser flash photolysis of aqueous solutions and their involvement in the photodehalogenation was firmly demonstrated. Identification by quantum calculations of two distinct triplet species supports the experimental results. The short‐ and long‐lived triplets are assigned respectively to the planar and non planar structures. Both were successfully detected experimentally. The non planar triplet either reacted with water to yield the dihydroxyderivative or gave the triplet carbene after heterolytic halogen elimination. These findings shed a new light on our understanding of the halogenophenols photochemistry and could be exploited in further studies.
Effect of Amide Bonds on the Self‐Assembly of Two Synthesized Sulphonamido Group Based Amphiphiles: Application in Formation of Stable Silver Nanoparticles.
Authors: Kar Byomkesh , Roy Sumita 
Published: September 2016

AbstractTwo new benzenesulphonamido group containing anionic amphiphiles named Sodium[11‐benzenesulphonamido‐undecanoate] (SBSAU) and Sodium[11‐benzenesulphonamido‐undecanamido]ethanoate (SBSAUG) have synthesized and characterized by FT‐IR, 1H‐NMR and LC–Mass spectroscopy. The surface properties of the amphiphiles have evaluated by tensiometry measurement. Steady state fluorescence measurement revealed the microenvironment of the self‐assemblies are very rigid and non polar. DLS study indicated formation of larger aggregates in solution. Formation of intermolecular hydrogen bonds through amide linkage and sulphonamide group has been established by 1H‐NMR study. XRD measurement was performed to realize the arrangement of the hydrocarbon chains in the lamellar structure. Presence of closed aqueous compartment was confirmed by GPC analysis. TEM micrographs showed that closed bilayer vesicles are formed in aqueous solutions of the amphiphiles. The permeable nature of the vesicle wall was investigated by kinetic study using riboflavin as probe molecule. Both the amphiphiles have successfully utilized to prepare stable silver nanoparticle.
A New Oxopiperazin‐Based Peptidomimetic Molecule Inhibits Prostatic Acid Phosphatase Secretion and Induces Prostate Cancer Cell Apoptosis
Authors: Zer Aviv Pinchas , Shubely Moran , Moskovits Yoni , Viskind Olga , Albeck Amnon , Vertommen Didier , Ruthstein Sharon , Shokhen Michael , Gruzman Arie 
Published: September 2016

AbstractReduced Prostatic acid Phosphatase (PAcP) secretion is associated with inhibition of the proliferation rate of prostate cancer cells. Signal peptidase 1 (SPase 1) is the main protease that cleaves the signal peptide of secretory proteins and allows their secretion. Thus, we hypothesised that inhibition of SPase 1 might lead to an antiproliferative effect in prostate cancer cells. Using homology computer modelling, we created a human SPase 1 model. With this model we designed and synthesised four novel (S)‐3‐(4‐aminobutyl)piperazin‐2‐one‐based peptidomimetics. The in vitro cytotoxic activity of these compounds was evaluated in the Lymph Node Carcinoma of the Prostate (LNCaP) cancer cell line. Indeed, (S)‐(3‐(2‐(4‐(((benzyloxy)carbonyl)amino)butyl)‐4‐(3‐methoxy‐3‐oxopropyl)‐3‐oxopiperazin‐1‐yl)propyl)boronic acid, compound 8) reduced PAcP secretion, as well as exhibited significant cytotoxic effect in LNAcP cells. As reported in this study, an antiprostate cancer drug development approach, which is based on inhibiting PAcP secretion, is innovative and it might serve as source for developing novel antiprostate cancer drugs.
Genetic Engineering of Silaffin‐Like Peptides for Binding and Precipitating Siliceous Materials
Authors: Drathen Anne , Reiber Jens , Krumm Christian , Meuris Monika , Tiller Joerg C. , Niemeyer Christof M. , Brakmann Susanne 
Published: September 2016

AbstractA cell surface‐displayed peptide library was employed for the selection of peptides with the capacity to bind fluorescent silica nanoparticles. The outcome of this approach enabled us to identify attributes important for recognition and binding the chosen siliceous material. Two of the peptides that were identified in the course of these experiments were studied in further detail and shown not only to bind silica nanoparticles with high affinity (Kd ∼ 100 nM) but also to induce the enrichment and precipitation of silica at the bacterial cell wall.