bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reaction mechanism and modeling study for the oxidation by SO2 of o‐xylene and p‐xylene in Claus process
Authors: Sinha Sourab , Raj Abhijeet 
Published: December 2017

AbstractClaus process, comprising of a furnace and a catalytic unit, is used to produce sulfur from H2S. The aromatic contaminants (benzene, toluene, and xylenes) in H2S feed form soot, and clog and deactivate the catalysts. Xylenes are known to be the most damaging ones. Therefore, there is a need to oxidize them in the furnace to enhance catalyst life. This article presents a kinetics study on the oxidation of o‐ and p‐xylene radicals by SO2 (an oxidant that is already present in the furnace) using density functional theory and a composite method. The mechanism begins with H‐abstraction from xylenes to form xylyl radicals, followed by exothermic addition of SO2 to them. The breakage of OS bond in the xylyl‐SO2 adducts leads to the loss of SO molecule, while the remaining O atom on them helps in their oxidation. The isomerization study shows that less‐stable dimethylphenyl radicals have a high tendency to isomerize to resonantly stabilized methylbenzyl radicals. However, methylbenzyl radicals have lower reactivity toward SO2 than dimethylphenyl radicals. The reaction rate constants were found using transition state theory. The reactor simulations reveal that p‐xylene has lower reactivity toward SO2 than o‐xylene, and CO, SO, and CHO are the main by‐products of oxidation.
Complex martingales and asymptotic enumeration
Authors: Isaev Mikhail , McKay Brendan D. 
Published: December 2017

AbstractMany enumeration problems in combinatorics, including such fundamental questions as the number of regular graphs, can be expressed as high‐dimensional complex integrals. Motivated by the need for a systematic study of the asymptotic behavior of such integrals, we establish explicit bounds on the exponentials of complex martingales. Those bounds applied to the case of truncated normal distributions are precise enough to include and extend many enumerative results of Barvinok, Canfield, Gao, Greenhill, Hartigan, Isaev, McKay, Wang, Wormald, and others. Our method applies to sums as well as integrals. As a first illustration of the power of our theory, we considerably strengthen existing results on the relationship between random graphs or bipartite graphs with specified degrees and the so‐called β‐model of random graphs with independent edges, which is equivalent to the Rasch model in the bipartite case.
Navigating Market Authorization: The Path Holoclar Took to Become the First Stem Cell Product Approved in the European Union
Authors: Pellegrini Graziella , Ardigò Diego , Milazzo Giovanni , Iotti Giorgio , Guatelli Paolo , Pelosi Danilo , De Luca Michele 
Published: December 2017

Abstract
Gene therapy, cell therapy, and tissue engineering have the potential to revolutionize the treatment of disease and injury. Attaining marketing authorization for such advanced therapy medicinal products (ATMPs) requires a rigorous scientific evaluation by the European Medicines Agency—authorization is only granted if the product can fulfil stringent requirements for quality, safety, and efficacy. However, many ATMPs are being provided to patients under alternative means, such as “hospital exemption” schemes. Holoclar (ex vivo expanded autologous human corneal epithelial cells containing stem cells), a novel treatment for eye burns, is one of the few ATMPs to have been granted marketing authorization and is the first containing stem cells. This review highlights the differences in standards between an authorized and unauthorized medicinal product, and specifically discusses how the manufacture of Holoclar had to be updated to achieve authorization. The result is that patients will have access to a therapy that is manufactured to high commercial standards, and is supported by robust clinical safety and efficacy data.
Osteogenic Stimulation of Human Adipose-Derived Mesenchymal Stem Cells Using a Fungal Metabolite That Suppresses the Polycomb Group Protein EZH2
Authors: Samsonraj Rebekah M. , Dudakovic Amel , Manzar Bushra , Sen Buer , Dietz Allan B. , Cool Simon M. , Rubin Janet , van Wijnen Andre J. 
Published: December 2017

Abstract
Strategies for musculoskeletal tissue regeneration apply adult mesenchymal stem/stromal cells (MSCs) that can be sourced from bone marrow- and lipo-aspirates. Adipose tissue-derived MSCs are more easily harvested in the large quantities required for skeletal tissue-engineering approaches, but are generally considered to be less osteogenic than bone marrow MSCs. Therefore, we tested a new molecular strategy to improve their osteogenic lineage-differentiation potential using the fungal metabolite cytochalasin D (CytoD). We show that CytoD, which may function by redistributing the intracellular location of β-actin (ACTB), is a potent osteogenic stimulant as reflected by significant increases in alkaline phosphatase activity, extracellular matrix mineralization, and osteoblast-related gene expression (e.g., RUNX2, ALPL, SPARC, and TGFB3). RNA sequencing analyses of MSCs revealed that acute CytoD treatment (24 hours) stimulates a broad program of osteogenic biomarkers and epigenetic regulators. CytoD decreases mRNA and protein levels of the Polycomb chromatin regulator Enhancer of Zeste Homolog 2 (EZH2), which controls heterochromatin formation by mediating trimethylation of histone 3 lysine 27 (H3K27me3). Reduced EZH2 expression decreases cellular H3K27me3 marks indicating a global reduction in heterochromatin. We conclude that CytoD is an effective osteogenic stimulant that mechanistically functions by blocking both cytoplasmic actin polymerization and gene-suppressive epigenetic mechanisms required for the acquisition of the osteogenic phenotype in adipose tissue-derived MSCs. This finding supports the use of CytoD in advancing the osteogenic potential of MSCs in skeletal regenerative strategies.
A High Aspect Ratio Serpentine Structure for Use As a Strain‐Insensitive, Stretchable Transparent Conductor
Authors: Jang Sungwoo , Kim Choelgyu , Park Jung Jin , Jin Ming Liang , Kim Seon Joon , Park O Ok , Kim Taek‐Soo , Jung Hee‐Tae 
Published: December 2017

AbstractThe development of strain‐insensitive stretchable transparent conductors (TCs) is essential for manufacturing stretchable electronics. Despite recent progress, achieving a high optoelectronic performance under applied strain of 50% continues to present a significant challenge in this research field. Herein, an ultratall and ultrathin high aspect ratio serpentine metal structure is described that exhibits a remarkable stretching ability (the resistance remains constant under applied strain of 100%) and simultaneously provides an excellent transparent conducting performance (with a sheet resistance of 7.6 Ω −1 and a transmittance of 90.5%). It is demonstrated that the highly stretchable transparent conducting properties can be attributed to the high aspect ratio feature. A high aspect ratio (aspect ratio of 17–367) structure permits facile deformation of the serpentine structure with in‐plane motion, leading to a high stretching ability. In addition, this structural feature avoids the classic tradeoff between optical transmittance and electrical conductance, providing a high electrical conductance without decreasing the optical transmittance. The practical utility of these devices is tested by using these TCs as stretchable interconnectors among LEDs or in wearable VOC gas sensors.
Multifunctional Interlayer Based on Molybdenum Diphosphide Catalyst and Carbon Nanotube Film for Lithium–Sulfur Batteries
Authors: Luo Yufeng , Luo Nannan , Kong Weibang , Wu Hengcai , Wang Ke , Fan Shoushan , Duan Wenhui , Wang Jiaping 
Published: December 2017

AbstractA multifunctional interlayer, composed of molybdenum diphosphide (MoP2) nanoparticles and a carbon nanotube (CNT) film, is introduced into a lithium–sulfur (Li–S) battery system to suppress polysulfide migration. Molybdenum diphosphide acts as the catalyst and can capture polysulfides and improve the polysulfide conversion activity during the discharge/charge processes. The CNT film acts as a conductive skeleton to support the MoP2 nanoparticles and to ensure their uniform distribution. The CNT film physically hinders polysulfide migration, acts as a current collector, and provides abundant electron pathways. The Li–S battery containing the multifunctional MoP2/CNT interlayer exhibits excellent electrochemical performance. It delivers a reversible specific capacity of 905 mA h g−1 over 100 cycles at 0.2 C, with a capacity decay of 0.152% per cycle. These results suggest the introduction of the multifunctional CNT/MoP2 interlayer as an effective and practical method for producing high‐performance Li–S batteries.
Design Principles of Functional Polymer Separators for High‐Energy, Metal‐Based Batteries
Authors: Zhang Weidong , Tu Zhengyuan , Qian Jiawei , Choudhury Snehashis , Archer Lynden A. , Lu Yingying 
Published: December 2017

AbstractNext‐generation rechargeable batteries that offer high energy density, efficiency, and reversibility rely on cell configurations that enable synergistic operations of individual components. They must also address multiple emerging challenges,which include electrochemical stability, transport efficiency, safety, and active material loss. The perspective of this Review is that rational design of the polymeric separator, which is used widely in rechargeable batteries, provides a rich set of opportunities for new innovations that should enable batteries to meet many of these needs. This perspective is different from the conventional view of the polymer separator as an inert/passive unit in a battery, which has the sole function to prevent direct contact between electrically conductivecomponents that form the battery anode and cathode. Polymer separators, which serve as the core component in a battery, bridge the electrodes and the electrolyte with a large surface contact that can be utilized to apply desirable functions. This Review focuses specifically on recent advances in polymer separator systems, with a detailed analysis of several embedded functional agents that are incorporated to improve mechanical robustness, regulate ion and mass transport, and retard flammability. The discussion is also extended to new composite separator concepts that are designated traditionally as polymer/gel electrolytes.
Solution‐Processed Metal Coating to Nonwoven Fabrics for Wearable Rechargeable Batteries
Authors: Lee Kyulin , Choi Jin Hyeok , Lee Hye Moon , Kim Ki Jae , Choi Jang Wook 
Published: December 2017

AbstractWearable rechargeable batteries require electrode platforms that can withstand various physical motions, such as bending, folding, and twisting. To this end, conductive textiles and paper have been highlighted, as their porous structures can accommodate the stress built during various physical motions. However, fabrics with plain weaves or knit structures have been mostly adopted without exploration of nonwoven counterparts. Also, the integration of conductive materials, such as carbon or metal nanomaterials, to achieve sufficient conductivity as current collectors is not well‐aligned with large‐scale processing in terms of cost and quality control. Here, the superiority of nonwoven fabrics is reported in electrochemical performance and bending capability compared to currently dominant woven counterparts, due to smooth morphology near the fiber intersections and the homogeneous distribution of fibers. Moreover, solution‐processed electroless deposition of aluminum and nickel–copper composite is adopted for cathodes and anodes, respectively, demonstrating the large‐scale feasibility of conductive nonwoven platforms for wearable rechargeable batteries.
Synergistic Interlayer and Defect Engineering in VS2 Nanosheets toward Efficient Electrocatalytic Hydrogen Evolution Reaction
Authors: Zhang Junjun , Zhang Chenhui , Wang Zhenyu , Zhu Jian , Wen Zhiwei , Zhao Xingzhong , Zhang Xixiang , Xu Jun , Lu Zhouguang 
Published: December 2017

AbstractA simple one‐pot solvothermal method is reported to synthesize VS2 nanosheets featuring rich defects and an expanded (001) interlayer spacing as large as 1.00 nm, which is a ≈74% expansion as relative to that (0.575 nm) of the pristine counterpart. The interlayer‐expanded VS2 nanosheets show extraordinary kinetic metrics for electrocatalytic hydrogen evolution reaction (HER), exhibiting a low overpotential of 43 mV at a geometric current density of 10 mA cm−2, a small Tafel slope of 36 mV dec−1, and long‐term stability of 60 h without any current fading. The performance is much better than that of the pristine VS2 with a normal interlayer spacing, and even comparable to that of the commercial Pt/C electrocatalyst. The outstanding electrocatalytic activity is attributed to the expanded interlayer distance and the generated rich defects. Increased numbers of exposed active sites and modified electronic structures are achieved, resulting in an optimal free energy of hydrogen adsorption (∆GH) from density functional theory calculations. This work opens up a new door for developing transition‐metal dichalcogenide nanosheets as high active HER electrocatalysts by interlayer and defect engineering.
A Freestanding and Long‐Life Sodium–Selenium Cathode by Encapsulation of Selenium into Microporous Multichannel Carbon Nanofibers
Authors: Yuan Beibei , Sun Xizhen , Zeng Linchao , Yu Yan , Wang Qingsong 
Published: December 2017

AbstractSelenium cathode has attracted more and more attention because of its comparable volumetric capacity but much higher electrical conductivity than sulfur cathode. Compared to Li–Se batteries, Na–Se batteries show many advantages, including the low cost of sodium resources and high volumetric capacity. However, Na–Se batteries still suffer from the shuttle effect of polyselenides and high volumetric expansion, resulting in the poor electrochemical performance. Herein, Se is impregnated into microporous multichannel carbon nanofibers (Se@MCNFs) thin film with high flexibility as a binder‐free cathode material for Na–Se batteries. The fibrous unique structure of the Se@MCNFs is beneficial to alleviate the volume change of Se during cycling, improve the utilization of active material, and suppress the dissolution of polyselenides into electrolyte. The freestanding Se@MCNF thin‐film electrode exhibits high discharge capacity (596 mA h g−1 at the 100th cycle at 0.1 A g−1) and excellent rate capability (379 mA h g−1 at 2 A g−1) for Na–Se batteries. In addition, it also shows long cycle life with a negligible capacity decay of 0.067% per cycle over 300 cycles at 0.5 A g−1. This work demonstrates the possibility to develop high performance Na–Se batteries and flexible energy storage devices.
Morphological and Compositional Design of Pd–Cu Bimetallic Nanocatalysts with Controllable Product Selectivity toward CO2 Electroreduction
Authors: Zhu Wenjin , Zhang Lei , Yang Piaoping , Chang Xiaoxia , Dong Hao , Li Ang , Hu Congling , Huang Zhiqi , Zhao Zhi‐Jian , Gong Jinlong 
Published: December 2017

AbstractElectrochemical conversion of carbon dioxide (electrochemical reduction of carbon dioxide) to value‐added products is a promising way to solve CO2 emission problems. This paper describes a facile one‐pot approach to synthesize palladium–copper (Pd–Cu) bimetallic catalysts with different structures. Highly efficient performance and tunable product distributions are achieved due to a coordinative function of both enriched low‐coordinated sites and composition effects. The concave rhombic dodecahedral Cu3Pd (CRD‐Cu3Pd) decreases the onset potential for methane (CH4) by 200 mV and shows a sevenfold CH4 current density at −1.2 V (vs reversible hydrogen electrode) compared to Cu foil. The flower‐like Pd3Cu (FL‐Pd3Cu) exhibits high faradaic efficiency toward CO in a wide potential range from −0.7 to −1.3 V, and reaches a fourfold CO current density at −1.3 V compared to commercial Pd black. Tafel plots and density functional theory calculations suggest that both the introduction of high‐index facets and alloying contribute to the enhanced CH4 current of CRD‐Cu3Pd, while the alloy effect is responsible for high CO selectivity of FL‐Pd3Cu.
Fluid Mixing for Low‐Power ‘Digital Microfluidics’ Using Electroactive Molecular Monolayers
Authors: Maglione Maria Serena , Casalini Stefano , Georgakopoulos Stamatis , Barbalinardo Marianna , Parkula Vitaliy , Crivillers Núria , Rovira Concepció , Greco Pierpaolo , Mas‐Torrent Marta 
Published: December 2017

AbstractA switchable electrode, which relies on an indium‐tin oxide conductive substrate coated with a self‐assembled monolayer terminated with an anthraquinone group (AQ), is reported as an electrowetting system. AQ electrochemical features confer the capability of yielding a significant modulation of surface wettability as high as 26° when its redox state is switched. Hence, an array of planar electrodes for droplets actuation is fabricated and integrated in a microfluidic device to perform mixing and dispensing on sub‐nanoliter scale. Vehiculation of cells across microfluidic compartments is made possible by taking full advantage of surface electrowetting in culture medium.
Does freeze‐all policy affect IVF outcome in poor ovarian responders?
Authors: Roque M. , Valle M. , Sampaio M. , Geber S. 
Published: December 2017

ABSTRACTObjectiveTo evaluate whether the freeze‐all strategy affects in‐vitro fertilization (IVF) outcome in poor ovarian responders (POR) defined according to the Bologna criteria.MethodThis was a retrospective cohort study of patients undergoing IVF treatment between January 2012 and December 2016 at a single center. A total of 433 POR (as defined by the Bologna criteria) fulfilled criteria and were included in the study; of these, 277 patients underwent fresh embryo transfer (ET) and 156 followed the freeze‐all policy. All patients underwent controlled ovarian stimulation (COS) following a gonadotropin‐releasing hormone antagonist protocol, and cleavage‐stage ET. Main outcome measure was ongoing pregnancy rate. Secondary outcomes included implantation and clinical pregnancy rates. The freeze‐all strategy was implemented when the progesterone serum level was > 1.5 ng/mL or the endometrium was < 7 mm on the trigger day, or as per patient preference. Patients with previous failed fresh ET also underwent fresh ET or freeze‐all strategy considering the indications mentioned above.ResultsMean maternal age in the freeze‐all group was 39.5 ± 3.6 years and in the fresh ET group was 39.7 ± 3.8 years (P = 0.54). Mean number of embryos transferred (nET) was 1.53 ± 0.6 and 1.60 ± 0.6 (P = 0.12) in the freeze‐all and fresh ET groups, respectively. Ongoing pregnancy rate did not differ significantly between the freeze‐all and fresh ET groups (9.6% vs 10.1%, respectively; relative risk (RR), 0.95; 95% CI, 0.52–1.73), nor did the clinical pregnancy rate (14.1% vs 13.7%, respectively; RR, 1.03; 95% CI, 0.63–1.67). Implantation rate was 9.6% and 9.8% (P = 0.82) in the freeze‐all and fresh ET groups, respectively. Logistic regression analysis (including maternal age, antral follicle count, number of retrieved and mature oocytes, nET, and fresh ET vs freeze‐all strategy) indicated that maternal age (P < 0.001) and nET (P = 0.039) were the only independent variables associated with ongoing pregnancy rate.ConclusionsThe freeze‐all strategy, compared with fresh ET, had no impact on IVF outcomes in POR patients as defined according to the Bologna criteria. Multicenter studies including large numbers of patients should be carried out to confirm the results of this study and reach conclusions about the potential benefits of the freeze‐all policy for poor responders. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.
The GW approximation: content, successes and limitations
Authors: Reining Lucia 
Published: December 2017

Many observables such as the density, total energy, or electric current, can be expressed explicitly in terms of the one‐body Green's function, which describes electron addition or removal to or from a system. An efficient way to determine such a Green's function is to introduce a self‐energy, which is a nonlocal and dynamic effective potential that influences the propagation of particles in an interacting system. The state‐of‐the art approximation for the self‐energy is the GW approximation, where the system to (or from) which the electron is added (or removed) is described as a polarizable, screening, medium. This is expressed by the name of the approximation: ‘GW’ stands for the one‐body Green's function G and for W, the dynamically screened Coulomb interaction. The GW approximation is very popular for the calculation of band structures in solids, and increasingly used also to describe nanostructures, clusters, and molecules. As compared to static mean‐field approximations for the effective potential, the dynamical screening of the Coulomb interaction in GW leads to a renormalization of energies, to broadening and/or to the observation of additional excitations. An analysis of the approximations that lead to the GW self‐energy, and of the underlying picture, explains the successes and the limitations of the approach.This article is categorized under:

Electronic Structure Theory > Density Functional Theory
Electronic Structure Theory > Ab Initio Electronic Structure Methods
Theoretical and Physical Chemistry > Spectroscopy
Structure and Mechanism > Computational Materials Science
International Study of the Epidemiology of Paediatric Trauma: PAPSA Research Study
Authors: Bradshaw Catherine J. , Bandi Ashwath S. , Muktar Zahid , Hasan Muhammad A. , Chowdhury Tanvir K. , Banu Tahmina , Hailemariam Mesay , Ngu Florence , Croaker David , Bankolé Rouma , Sholadoye Tunde , Olaomi Oluwole , Ameh Emmanuel , Di Cesare Antonio , Leva Ernesto , Ringo Yona , Abdur‐Rahman Lukman , Salama Ramy , Elhalaby Essam , Perera Helen , Parsons Christopher , Cleeve Stewart , Numanoglu Alp , Van As Sebastian , Sharma Shilpa , Lakhoo Kokila 
Published: December 2017

AbstractObjectivesTrauma is a significant cause of morbidity and mortality worldwide. The literature on paediatric trauma epidemiology in low‐ and middle‐income countries (LMICs) is limited. This study aims to gather epidemiological data on paediatric trauma.MethodsThis is a multicentre prospective cohort study of paediatric trauma admissions, over 1 month, from 15 paediatric surgery centres in 11 countries. Epidemiology, mechanism of injury, injuries sustained, management, morbidity and mortality data were recorded. Statistical analysis compared LMICs and high‐income countries (HICs).ResultsThere were 1377 paediatric trauma admissions over 31 days; 1295 admissions across ten LMIC centres and 84 admissions across five HIC centres. Median number of admissions per centre was 15 in HICs and 43 in LMICs. Mean age was 7 years, and 62% were boys. Common mechanisms included road traffic accidents (41%), falls (41%) and interpersonal violence (11%). Frequent injuries were lacerations, fractures, head injuries and burns. Intra‐abdominal and intra‐thoracic injuries accounted for 3 and 2% of injuries. The mechanisms and injuries sustained differed significantly between HICs and LMICs. Median length of stay was 1 day and 19% required an operative intervention; this did not differ significantly between HICs and LMICs. No mortality and morbidity was reported from HICs. In LMICs, in‐hospital morbidity was 4.0% and mortality was 0.8%.ConclusionThe spectrum of paediatric trauma varies significantly, with different injury mechanisms and patterns in LMICs. Healthcare structure, access to paediatric surgery and trauma prevention strategies may account for these differences. Trauma registries are needed in LMICs for future research and to inform local policy.