bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cerebral microdialysis
Authors: Mahajan Charu , Rath Girija 
Published: September 2015

AbstractCerebral microdialysis is one of the latest neuromonitoring modalities introduced to clinical practice. It is a bedside monitor used to assess brain tissue biochemistry. The principle of this technique is closely related to brain metabolism and dialysis. Microdialysis helps monitoring different metabolites related to energy and metabolic cascades (glucose, lactate and pyruvate), amino acids (glutamate) and markers of cell membrane degradation (glycerol). Its role has been established in conditions such as traumatic brain injury, subarachnoid haemorrhage, ischaemic stroke, etc. However, it is yet to be included in routine neuromonitoring as the technique is very expensive, needs technical expertise and the measurement is not continuous with a lag period in-between two readings. Till date, it is mostly used as a research tool, even though it is a very promising technique in certain clinical conditions.
A Novel Low-Dimensional Method for Analytically Solving Partial Differential Equations
Authors: Sha Jie , Zhang Lixiang , Wu Chuijie 
Published: September 2015

AbstractThis paper is concerned with a low-dimensional dynamical system model for analytically solving partial differential equations (PDEs). The model proposed is based on a posterior optimal truncated weighted residue (POT-WR) method, by which an infinite dimensional PDE is optimally truncated and analytically solved in required condition of accuracy. To end that, a POT-WR condition for PDE under consideration is used as a dynamically optimal control criterion with the solving process. A set of bases needs to be constructed without any reference database in order to establish a space to describe low-dimensional dynamical system that is required. The Lagrangian multiplier is introduced to release the constraints due to the Galerkin projection, and a penalty function is also employed to remove the orthogonal constraints. According to the extreme principle, a set of ordinary differential equations is thus obtained by taking the variational operation of the generalized optimal function. A conjugate gradient algorithm by FORTRAN code is developed to solve the ordinary differential equations. The two examples of one-dimensional heat transfer equation and nonlinear Burgers’ equation show that the analytical results on the method proposed are good agreement with the numerical simulations and analytical solutions in references, and the dominant characteristics of the dynamics are well captured in case of few bases used only.
Electron energetics in the expanding solar wind via Helios observations
Authors: Štverák Štěpán , Trávníček Pavel M. , Hellinger Petr 
Published: September 2015

AbstractWe present an observational analysis of electron cooling/heating rates in the fast and slow solar wind between 0.3 and 1 AU. We fit electron velocity distribution functions acquired in situ by Helios 1 and 2 spacecraft by a three‐component (core‐halo‐strahl) analytical model. The resulting radial profiles of macroscopic characteristics (density, temperatures, and heat fluxes) are employed to examine properties of theoretical energy balance equations and to estimate external cooling/heating terms. Our analysis indicates that in contrast to solar wind protons the electrons do not require important heating mechanisms to explain the observed temperature gradients. The electron heating rates are actually found to be negative for both the slow and fast solar wind, namely, due to the significant degradation of the electron heat flux with increasing radial distance from the Sun. Cooling mechanisms acting on electrons are found to be significantly stronger in the slow wind than in the fast wind streams.
Isocyanates and work‐related asthma: Findings from California, Massachusetts, Michigan, and New Jersey, 1993–2008
Authors: Lefkowitz Daniel , Pechter Elise , Fitzsimmons Kathleen , Lumia Margaret , Stephens Alicia C. , Davis Letitia , Flattery Jennifer , Weinberg Justine , Harrison Robert J. , Reilly Mary Jo , Filios Margaret S. , White Gretchen E. , Rosenman Kenneth D. 
Published: September 2015

BackgroundIsocyanates remain a leading cause of work‐related asthma (WRA).MethodsTwo independent data systems were analyzed for the period 1993–2008: (1) State‐based WRA case surveillance data on persons with isocyanate‐induced WRA from four states, and (2) Occupational Safety and Health Administration (OSHA) Integrated Management Information System (IMIS) isocyanate air sampling results.ResultsWe identified 368 cases of isocyanate‐induced WRA from 32 industries and 678 OSHA isocyanate air samples with detectable levels from 31 industries. Seventeen industries were unique to one or the other dataset.ConclusionIsocyanate‐induced WRA continues to occur in a wide variety of industries. Two data systems uncovered industries with isocyanate exposures and/or illness. Improved control measures and standards, including medical surveillance, are needed. More emphasis is needed on task‐specific guidance, spill clean‐up procedures, skin and respiratory protection, and targeted medical monitoring to mitigate the hazards of isocyanate use. Am. J. Ind. Med. 58:1138–1149, 2015. © 2015 Wiley Periodicals, Inc.
An urgent need to understand and address the safety and well‐being of hospital “sitters”
Authors: Schoenfisch Ashley L. , Pompeii Lisa A. , Lipscomb Hester J. , Smith Claudia D. , Upadhyaya Mudita , Dement John M. 
Published: September 2015

BackgroundHospital sitters provide continuous observation of patients at risk of harming themselves or others. Little is known about sitters’ occupational safety and well‐being, including experiences with patient/visitor‐perpetrated violence (type II).MethodsData from surveys, focus groups, individual interviews at six U.S. hospitals were used to characterize the prevalence of and circumstance surrounding type II violence against sitters, as well as broader issues related to sitter use.ResultsSitter respondents had a high 12‐month prevalence of physical assault, physical threat, and verbal abuse compared to other workers in the hospital setting. Sitters and other staff indicated the need for clarification of sitters’ roles regarding patient care and sitter well‐being (e.g., calling for assistance, taking lunch/restroom breaks), training of sitters in personal safety and de‐escalation, methods to communicate patient/visitor behaviors, and unit‐level support.ConclusionsThe burden of type II violence against hospital sitters is concerning. Policies surrounding sitters’ roles and violence prevention training are urgently needed. Am. J. Ind. Med. 58:1278–1287, 2015. © 2015 Wiley Periodicals, Inc.
Oxidative Amidation of Nitroalkanes with Amine Nucleophiles using Molecular Oxygen and Iodine
Authors: Li Jing , Lear Martin J. , Kawamoto Yuya , Umemiya Shigenobu , Wong Alice R. , Kwon Eunsang , Sato Itaru , Hayashi Yujiro 
Published: September 2015

AbstractThe formation of amides and peptides often necessitates powerful yet mild reagent systems. The reagents used, however, are often expensive and highly elaborate. New atom‐economical and practical methods that achieve such goals are highly desirable. Ideally, the methods should start with substrates that are readily available in both chiral and non‐chiral forms and utilize cheap reagents that are compatible with a wide variety of functional groups, steric encumberance, and epimerizable stereocenters. A direct oxidative method was developed to form amide and peptide bonds between amines and primary nitroalkanes simply by using I2 and K2CO3 under O2. Contrary to expectations, a 1:1 halogen‐bonded complex forms between the iodonium source and the amine, which reacts with nitronates to form α‐iodo nitroalkanes as precursors to the amides.
Anziehung oder Abstoßung? London‐Dispersionswechselwirkungen kontrollieren Azobenzol‐basierte molekulare Schalter
Authors: Schweighauser Luca , Strauss Marcel A. , Bellotto Silvia , Wegner Hermann A. 
Published: September 2015

AbstractAufgrund sterischer Hinderung wird großen Substituenten im Allgemeinen eine rein abstoßende Wirkung zugesprochen. Solche Reste haben jedoch auch anziehende Eigenschaften, die durch schwache London‐Dispersionskräfte zwischen den neutralen Atomen hervorgerufen werden. In Lehrbüchern wird sterische Hinderung häufig als Grund für die Destabilisierung des Z‐isomers genannt, z. B. bei Isomerisierungen wie bei Azobenzol‐basierten molekularen Schaltern. Hier zeigen wir, dass eine Vergrößerung der Substituenten in der meta‐Position des Azobenzols, unter Beibehaltung der elektronischen Struktur der Reste, die thermische Z‐zu‐E‐Isomerisierung verlangsamt. DFT‐Rechnungen untermauern, dass die Energie des Z‐Isomers durch anziehende Dispersionswechselwirkungen deutlich gesenkt wird.
Aerobic Asymmetric Dehydrogenative Cross‐Coupling between Two CH Groups Catalyzed by a Chiral‐at‐Metal Rhodium Complex
Authors: Tan Yuqi , Yuan Wei , Gong Lei , Meggers Eric 
Published: September 2015

AbstractA sustainable CC bond formation is merged with the catalytic asymmetric generation of one or two stereocenters. The introduced catalytic asymmetric cross‐coupling of two CH groups with molecular oxygen as the oxidant profits from the oxidative robustness of a chiral‐at‐metal rhodium(III) catalyst and exploits an autoxidation mechanism or visible‐light photosensitized oxidation. In the latter case, the catalyst serves a dual function, namely as a chiral Lewis acid for catalyzing enantioselective enolate chemistry and at the same time as a visible‐light‐driven photoredox catalyst.
Perylene Bisimide Radicals and Biradicals: Synthesis and Molecular Properties
Authors: Schmidt David , Son Minjung , Lim Jong Min , Lin Mei‐Jin , Krummenacher Ivo , Braunschweig Holger , Kim Dongho , Würthner Frank 
Published: September 2015

AbstractUnprecedented neutral perylene‐3,4:9,10‐tetracarboxylic acid bisimide (PBI) radicals and biradicals were synthesized by facile chemical oxidation of 4‐hydroxyaryl‐substituted PBIs. Subsequent characterization by optical and magnetic spectroscopic techniques, as well as quantum chemical calculations, revealed an open‐shell singlet biradical ground state for the PBI biradical OS‐2.. (〈s2〉=1.2191) with a relatively small singlet–triplet energy gap of 0.041 eV and a large singlet biradical character of y=0.72.
Sugar–Protein Connectivity Impacts on the Immunogenicity of Site‐Selective Salmonella O‐Antigen Glycoconjugate Vaccines
Authors: Stefanetti Giuseppe , Hu Qi‐Ying , Usera Aimee , Robinson Zack , Allan Martin , Singh Alok , Imase Hidetomo , Cobb Jennifer , Zhai Huili , Quinn Douglas , Lei Ming , Saul Allan , Adamo Roberto , MacLennan Calman A. , Micoli Francesca 
Published: September 2015

AbstractA series of glycoconjugates with defined connectivity were synthesized to investigate the impact of coupling Salmonella typhimurium O‐antigen to different amino acids of CRM197 protein carrier. In particular, two novel methods for site‐selective glycan conjugation were developed to obtain conjugates with single attachment site on the protein, based on chemical modification of a disulfide bond and pH‐controlled transglutaminase‐catalyzed modification of lysine, respectively. Importantly, conjugation at the C186‐201 bond resulted in significantly higher anti O‐antigen bactericidal antibody titers than coupling to K37/39, and in comparable titers to conjugates bearing a larger number of saccharides. This study demonstrates that the conjugation site plays a role in determining the immunogenicity in mice and one single attachment point may be sufficient to induce high levels of bactericidal antibodies.
Improving the toughness of epoxy with a reactive tetrablock copolymer containing maleic anhydride
Authors: He Ren , Zhan Xiaoli , Zhang Qinghua , Chen Fengqiu 
Published: September 2015

ABSTRACTReactive block copolymers (BCPs) provide a unique means for toughening epoxy thermosets because covalent linkages provide opportunities for greater improvement in the fracture toughness (KIC). In this study, a tailored reactive tetrablock copolymer, poly[styrene‐alt‐(maleic anhydride)]‐block‐polystyrene‐block‐poly(n‐butyl acrylate)‐block‐polystyrene, was incorporated into a diglycidyl ether of bisphenol A based epoxy resin. The results demonstrate the advantage of reactive BCP in finely tuning and controlling the structure of epoxy blends, even with 95 wt % epoxy‐immiscible triblocks. The size of the dispersed phase was efficiently reduced to submicrometer level. The mechanical properties, such asKIC,of these cured blends were investigated. The addition of 10 wt % reactive BCP into the epoxy resins led to considerable improvements in the toughness, imparting nearly a 70% increase inKIC. The designed reactive tetrablock copolymer opened good prospects because of its potential novel applications in toughening modification of engineering polymer composites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2016,132, 42826.
A newly thermoactive and detergent‐stable lipase from annular sea bream (Diplodus annularis): Biochemical properties
Authors: Smichi Nabil , Miled Nabil , Gargouri Youssef , Fendri Ahmed 
Published: September 2015

AbstractA lipolytic activity was located in the annular seabream pyloric caeca, from which a digestive lipase (AsDL) was purified. Pure AsDL has an apparent molecular mass of 50 kDa. The purified lipase is thermoactive as it displays its maximal activity on short‐ and long‐chain triacylglycerols at a temperature of 50 °C. The enzyme is alkaline resistant as it retains 90% of its maximal activity when incubated during 1 H at pH 10. No colipase was detected in the annular seabream pyloric caeca. Similar results were reported for the sardine and the gray mullet digestive systems. This is in line with the idea that colipase might have evolved in mammal animals simultaneously with the appearance of an exocrine pancreas. AsDL is a serine enzyme, like all known lipases from different origins. Interestingly, the pure lipase was found to be insensitive to Triton X‐100, a synthetic detergent, addition even at a concentration as high as 12 mM. The purified enzyme has potential applications in detergent and food industry because of its thermal activity and alkaline nature.
Enhanced molecular dynamics sampling of drug target conformations
Authors: Rodriguez‐Bussey Isela G. , Doshi Urmi , Hamelberg Donald 
Published: September 2015

ABSTRACTComputational docking and virtual screening are two main important methods employed in structure‐based drug design. Unlike the traditional approach that allows docking of a flexible ligand against a handful of receptor structures, receptor flexibility has now been appreciated and increasingly incorporated in computer‐aided docking. Using a diverse set of receptor conformations increases the chances of finding potential drugs and inhibitors. Molecular dynamics (MD) is greatly useful to generate various receptor conformations. However, the diversity of the structures of the receptor, which is usually much larger than the ligand, depends on the sampling efficiency of MD. Enhanced sampling methods based on accelerated molecular dynamics (aMD) can alleviate the sampling limitation of conventional MD and aid in representation of the phase space to a much greater extent. RaMD‐db, a variant of aMD that applies boost potential to the rotatable dihedrals and non‐bonded diffusive degrees of freedom has been proven to reproduce the equilibrium properties more accurately and efficiently than aMD. Here, we discuss recent advances in the aMD methodology and review the applicability of RaMD‐db as an enhanced sampling method. RaMD‐db is shown to be able to generate a broad distribution of structures of a drug target, Cyclophilin A. These structures that have never been observed previously in very long conventional MD can be further used for structure‐based computer‐aided drug discovery, and docking, and thus, in the identification and design of potential novel inhibitors. © 2015 Wiley Periodicals, Inc. Biopolymers 105: 35–42, 2016.
Development of a Magnetically Recyclable Molybdenum Disulfide Catalyst for Direct Hydrodesulfurization
Authors: Sharifvaghefi Seyyedmajid , Zheng Ying 
Published: September 2015

AbstractSuperparamagnetic MoS2/SiO2/Fe3O4 catalysts that consist of magnetite as the core, silica as the covering layer, and molybdenum sulfide as the top layer were prepared in easy steps. Two different surfactants (anionic and cationic) were used to assist with the synthesis of two of the samples, and one sample was prepared without surfactant. The surfactant was found to have a significant effect on the properties and activity of the final catalysts. Hydrodesulfurization (HDS) tests of the catalysts show higher activity for the cationic‐surfactant‐assisted catalyst. Between the direct desulfurization (DDS) and hydrogenation pathways for the prepared catalysts, the DDS pathway was found to be dominant for the HDS of dibenzothiophene. As a result of the magnetic properties of this catalyst, it can be separated easily from the reaction media by a magnetic field applied externally and reused, which makes it an ideal choice for slurry reactors that process heavy and extra‐heavy crude oil.
Controllable Fabrication of Tungsten Oxide Nanoparticles Confined in Graphene‐Analogous Boron Nitride as an Efficient Desulfurization Catalyst
Authors: Wu Peiwen , Zhu Wenshuai , Wei Aimin , Dai Bilian , Chao Yanhong , Li Changfeng , Li Huaming , Dai Sheng 
Published: September 2015

AbstractTungsten oxide nanoparticles (WOxNPs) are gaining increasing attention, but low stabiliity and poor dispersion of WOxNPs hinder their catalytic applications. Herein, WOxNPs were confined in graphene‐analogous boron nitride (g‐BN) by a one‐step, in situ method at high temperature, which can enhance the interactions between WOxNPs and the support and control the sizes of WOxNPs in a range of about 4–5 nm. The as‐prepared catalysts were applied in catalytic oxidation of aromatic sulfur compounds in which they showed high catalytic activity. A balance between the W loading and the size distribution of the WOxNPs could govern the catalytic activity. Furthermore, a synergistic effect between g‐BN and WOxNPs also contributed to high catalytic activity. The reaction mechanism is discussed in detail and the catalytic scope was enlarged.
Frame‐Guided Assembly of Amphiphiles
Authors: Dong Yuanchen , Liu Dongsheng 
Published: September 2015

AbstractFrame‐guided assembly, a recently discovered strategy for amphiphilic assembly, is discussed as a strategy for constructing vesicle assemblies with programmed geometries and dimensions under identical surrounding conditions. The strategy is inspired by the cytoskeletal‐membrane protein–lipid bilayer structure and shows great potential in the understanding and controlling of the amphiphilic assembly process. Both the principles and basic requirements are discussed, along with recently reported examples. The prospects and potential investigations of frame‐guided assembly are also proposed.
Chiral SiO2 and Ag@SiO2 Materials Templated by Complexes Consisting of Comblike Polyethyleneimine and Tartaric Acid
Authors: Yao Dong‐Dong , Murata Hiroki , Tsunega Seiji , Jin Ren‐Hua 
Published: September 2015

AbstractA facile avenue to fabricate micrometer‐sized chiral (L‐, D‐) and meso‐like (dl‐) SiO2 materials with unique structures by using crystalline complexes (cPEI/tart), composed of comblike polyethyleneimine (cPEI) and L‐, D‐, or dl‐tartaric acid, respectively, as catalytic templates is reported. Interestingly, both chiral crystalline complexes appeared as regularly left‐ and right‐twisted bundle structures about 10 μm in length and about 5 μm in diameter, whereas the dl‐form occurred as circular structures with about 10 μm diameter. Subsequently, SiO2@cPEI/tart hybrids with high silica content (>55.0 wt %) were prepared by stirring a mixture containing tetramethoxysilane (TMOS) and the aggregates of the crystalline complexes in water. The chiral SiO2 hybrids and calcined chiral SiO2 showed very strong CD signals and a nanofiber‐based morphology on their surface, whereas dl‐SiO2 showed no CD activity and a nanosheet‐packed disklike shape. Furthermore, metallic silver nanoparticles (Ag NPs) were encapsulated in each silica hybrid to obtain chiral (D and L forms) and meso‐like (dl form) Ag@SiO2 composites. Also, the reaction between L‐cysteine (Lcys) and these Ag@SiO2 composites was preliminarily investigated. Only chiral L‐ and D‐Ag@SiO2 composites promoted the reaction between Lcys and Ag NPs to produce a molecular [Ag–Lcys]n complex with remarkable exciton chirality, whereas the reaction hardly occurred in the case of meso‐like (dl‐) Ag@SiO2 composite.
Supracolloidal Architectures Self‐Assembled in Microdroplets
Authors: Xu Xuejiao , Tian Feng , Liu Xin , Parker Richard M. , Lan Yang , Wu Yuchao , Yu Ziyi , Scherman Oren A. , Abell Chris 
Published: September 2015

AbstractWe demonstrate a novel method for the formation of a library of structured colloidal assemblies by exploiting the supramolecular heteroternary host–guest interaction between cucurbit[8]uril (CB[8]) and methyl viologen‐ and naphthalene‐functionalised particles. The approach is dependent upon compartmentalisation in microdroplets generated by a microfluidic platform. Though the distribution of colloidal particles encapsulated within each microdroplet followed a Poisson distribution, tuning the concentration of the initial colloidal particle suspensions provided some level of control over the structure of the formed colloidal assemblies. This ability to direct the assembly of complementarily‐functionalised colloids through a supramolecular interaction, without the need for complex modification of the colloidal surface or external stimuli, presents an exciting new approach towards the design of structured colloidal materials with the potential to produce many challenging structures.
Transition Metal Oxides for the Oxygen Reduction Reaction: Influence of the Oxidation States of the Metal and its Position on the Periodic Table
Authors: Toh Rou Jun , Sofer Zdeněk , Pumera Martin 
Published: September 2015

AbstractElectrocatalysts have been developed to meet the needs and requirements of renewable energy applications. Metal oxides have been well explored and are promising for this purpose, however, many reports focus on only one or a few metal oxides at once. Herein, thirty metal oxides, which were either commercially available or synthesized by a simple and scalable method, were screened for comparison with regards to their electrocatalytic activity towards the oxygen reduction reaction (ORR). We show that although manganese, iron, cobalt, and nickel oxides generally displayed the ability to enhance the kinetics of oxygen reduction under alkaline conditions compared with bare glassy carbon, there is no significant correlation between the position of a metal on the periodic table and the electrocatalytic performance of its respective metal oxides. Moreover, it was also observed that mixed valent (+2, +3) oxides performed the poorest, compared with their respective pure metal oxides. These findings may be of paramount importance in the field of renewable energy.