bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spontaneous perforation of primary gastric B‐cell lymphoma of MALT: a case report and literature review
Authors: El Asmar Antoine , Khattar Fouad , Alam Marianne , El Rassi Ziad 
Published: October 2016

Key Clinical MessagePrimary gastric lymphoma is a rare malignant tumor that can sometimes present as spontaneous perforation. We present below a case of spontaneous primary gastric lymphoma perforation that was managed in our institution followed by a brief review of the literature and discussion.
Use of Cobalt Polyphthalocyanine and Graphene as Precursors to Construct an Efficient Co9S8/N,S‐G Electrocatalyst for the Oxygen Electrode Reaction in Harsh Media
Authors: Ma Xiu‐Xiu , Su Yan , He Xing‐Quan 
Published: October 2016

AbstractThe oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are fundamental reactions connected with energy conversion and/or storage devices. However, the sluggish kinetics of the ORR and OER reduce the efficiency. To address these issues, the development of efficient and robust electrode catalysts is required desperately. Herein, a new Co9S8 nanocrystal hybrid anchored on a N‐ and S‐dual‐doped graphene (Co9S8/N,S‐G) was prepared by a two‐step method, namely, a π–π assembly process of p‐phenyl‐bis(3,4‐dicyanophenyl)thioether cobalt polyphthalocyanine (PTCoPPc) and graphene oxide and a pyrolysis procedure. Electrochemical studies demonstrated that Co9S8(800)/N,S‐G exhibited a comparable ORR performance with 20 wt % Pt/C, such as an onset potential and a half‐wave potential of 0.931 and 0.811 V vs. the reversible hydrogen electrode, respectively, a limiting current density of 5.207 mA cm−2, and a good long‐term stability with a current retention of 92.6 % after 10 000 s continuous measurements. Co9S8(900)/N,S‐G displayed an excellent OER activity, which was ascribed to the presence of pyridinic N, graphitic N, and the occupation of Co−N to catalyze the ORR; and the oxygen adsorption on the surface of Co9S8(900)/N,S‐G contributed significantly to the OER activity. The approach developed here offered a new strategy to construct efficient oxygen electrode catalysts.
Suppression of the Aromatic Cycle in Methanol‐to‐Olefins Reaction over ZSM‐5 by Post‐Synthetic Modification Using Calcium
Authors: Yarulina Irina , Bailleul Simon , Pustovarenko Alexey , Martinez Javier Ruiz , Wispelaere Kristof De , Hajek Julianna , Weckhuysen Bert M. , Houben Klaartje , Baldus Marc , Van Speybroeck Veronique , Kapteijn Freek , Gascon Jorge 
Published: October 2016

AbstractThe front cover artwork for Issue 19/2016 is provided by researchers from the Catalysis Engineering group at TU Delft (The Netherlands). The image shows that after impregnation with Ca, ZSM‐5 becomes a “super‐catalyst”, which is able to suppress formation of aromatics thus increasing selectivity to the desired propylene in MTO reaction. See the Full Paper itself at http://dx.doi.org/10.1002/cctc.201600650.
Redox‐Active M8L6 Cubic Hosts with Tetraphenylethylene Faces Encapsulate Organic Dyes for Light‐Driven H2 Production
Authors: Yang Linlin , Jing Xu , He Cheng , Chang Zhiduo , Duan Chunying 
Published: October 2016

AbstractThe design of artificial systems that mimic highly evolved and finely tuned natural enzymes is a promising subject of intensive research. The assembly of O‐symmetric cubic structures with an Fe8L6 formula was reported through the direct combination of a C4‐symmetric tetraphenylethylene‐based ligand with a C3‐symmetric tris(bipyridine)iron node. The robust metal–organic cubes are rich in π‐electron density and provide favorable interactions with planar polycyclic aromatic hydrocarbons. Within the confined space of the host, the aromatic hydrocarbons molecules are forced closer to the redox active host, and the photoinduced electron transfer (PET) is modified into a pseudo‐intramolecular pathway. These iron vertices within the cubes exhibit suitable redox potential for electrochemical reduction of protons and the well‐modified PET is further tailored to create artificial systems for light‐driven hydrogen evolution from water through the encapsulation of fluorescein dyes. Control experiments based on a mononuclear compound resembling the iron corner of the octahedron suggest an enzymatic dynamic behavior. The new, well‐elucidated reaction pathways and the increased molarity of the reaction within the confined space render these supramolecular systems superior to other relevant systems.
Freezing the Dynamic Gap for Selectivity: Motion‐Based Design of Inhibitors of the Shikimate Kinase Enzyme
Authors: Prado Verónica , Lence Emilio , Thompson Paul , Hawkins Alastair R. , González‐Bello Concepción 
Published: October 2016

AbstractShikimate kinase (SK), the fifth enzyme of the aromatic amino acid biosynthesis, is a recognized target for antibiotic drug discovery. The potential of the distinct dynamic apolar gap, which isolates the natural substrate from the solvent environment for catalysis, and the motion of Mycobacterium tuberculosis and Helicobacter pylori SK enzymes, which was observed by molecular dynamics simulations, was explored for inhibition selectivity. The results of the biochemical and computational studies reveal that the incorporation of bulky groups at position C5 of 5‐aminoshikimic acid and the natural substrate enhances the selectivity for the H. pylori enzyme due to key motion differences in the shikimic acid binding domain (mainly helix α5). These studies show that the less‐exploited motion‐based design approach not only is an alternative strategy for the development of competitive inhibitors, but could also be a way to achieve selectivity against a particular enzyme among its homologues.
Natural Abundance 15N and 13C Solid‐State NMR Chemical Shifts: High Sensitivity Probes of the Halogen Bond Geometry
Authors: Cerreia Vioglio Paolo , Catalano Luca , Vasylyeva Vera , Nervi Carlo , Chierotti Michele R. , Resnati Giuseppe , Gobetto Roberto , Metrangolo Pierangelo 
Published: October 2016

AbstractSolid‐state nuclear magnetic resonance (SSNMR) spectroscopy is a versatile characterization technique that can provide a plethora of information complementary to single crystal X‐ray diffraction (SCXRD) analysis. Herein, we present an experimental and computational investigation of the relationship between the geometry of a halogen bond (XB) and the SSNMR chemical shifts of the non‐quadrupolar nuclei either directly involved in the interaction (15N) or covalently bonded to the halogen atom (13C). We have prepared two series of X‐bonded co‐crystals based upon two different dipyridyl modules, and several halobenzenes and diiodoalkanes, as XB‐donors. SCXRD structures of three novel co‐crystals between 1,2‐bis(4‐pyridyl)ethane, and 1,4‐diiodobenzene, 1,6‐diiodododecafluorohexane, and 1,8‐diiodohexadecafluorooctane were obtained. For the first time, the change in the 15N SSNMR chemical shifts upon XB formation is shown to experimentally correlate with the normalized distance parameter of the XB. The same overall trend is confirmed by density functional theory (DFT) calculations of the chemical shifts. 13C NQS experiments show a positive, linear correlation between the chemical shifts and the C−I elongation, which is an indirect probe of the strength of the XB. These correlations can be of general utility to estimate the strength of the XB occurring in diverse adducts by using affordable SSNMR analysis.
Room‐Temperature Synthesis of Covalent Organic Frameworks with a Boronic Ester Linkage at the Liquid/Solid Interface
Authors: Liu Chunhua , Yu Yanxia , Zhang Wei , Zeng Qingdao , Lei Shengbin 
Published: October 2016

AbstractWith various prospected applications in the field of nanoelectronics and catalysis, on‐surface synthesis of single‐layer covalent organic frameworks (surface COFs) with designable structures and properties have attracted enormous interest. Herein, we report on a scanning tunneling microscopic investigation of the surface‐confined synthesis of a covalently bonded boronic ester network directly at the octanoic acid/ highly oriented pyrolytic graphite(HOPG) interface under room temperature. The dynamic reaction process was investigated in detail. STM results indicate that the surface networks undergo structural evolution from a hybrid covalent/noncovalent multiwall porous network to single‐wall hexagonal COF with the decrease of monomer concentration. Further experimental observation disclosed that the boronic ester‐linked system is sensitive to instantaneous voltage pulses and the stimulation of the STM tip. In addition, the 1H NMR spectra has further confirmed that the surface and octanoic acid may play important roles in promoting the reaction between 4,4′‐phenylazobenzoyl diboronic acid (ABBA) and 2,3,6,7,10,11‐hexahydroxytriphenylene (HHTP) building units.
m‐Methoxy Substituents in a Tetraphenylethylene‐Based Hole‐Transport Material for Efficient Perovskite Solar Cells
Authors: Wu Fei , Liu Jianlin , Wang Gang , Song Qunliang , Zhu Linna 
Published: October 2016

AbstractThree tetrapheynlethylene derivatives (N,N‐di(4‐methoxyphenyl)aminophenyl‐substituted tetraphenylethylene; TPE‐4DPA) with different methoxy positions (pp‐, pm‐, and po‐) have been synthesized and characterized. The methoxy groups can control the oxidation potential of the materials, and the electronic properties of the derivatives were affected by the position of the methoxy substituents. These compounds were synthesized in a facile and cost‐effective way, and were applied as hole‐transport materials in perovskite solar cells. The corresponding cell performances were compared with respect to their structure modifications, and it was found that the derivative with m‐OMe substituents showed the highest power conversion efficiency (PCE) of 15.4 %, with a Jsc value of 20.04 mA cm−2, a Voc value of 1.07 V, and a fill factor (FF) value of 0.72, which is higher than the p‐OMe and o‐OMe substituents. Moreover, the PCE of pm‐TPE‐4DPA is comparable with that of the state‐of‐the‐art 2,2′,7,7′‐tetrakis(N,N′‐di‐p‐methoxyphenylamine)‐9,9′‐spirobifluorene under identical conditions.
Does Topology Dictate the Incidence of the Twist‐Bend Phase? Insights Gained from Novel Unsymmetrical Bimesogens
Authors: Mandle Richard J. , Goodby John W. 
Published: October 2016

AbstractWe prepared a significant number of unsymmetrical liquid‐crystalline dimers that exhibit the twist‐bend nematic phase; a state of matter that exhibits spontaneous breaking of mirror symmetry and, for some materials, a microsecond electrooptic response. A number of novel unsymmetrical bimesogens were synthesized and in comparing their thermal behaviour to previous literature examples, we have uncovered an unexpected relationship between the thermal stability of the nematic and NTB phases. This relationship demonstrates that molecular shape dictates the incidence of this fascinating phase of matter and leads us to speculate as to the existence of “twist‐bend nematic phases” on length scales beyond those of the molecule.
Carbon Nanotube/Boron Nitride Nanocomposite as a Significant Bifunctional Electrocatalyst for Oxygen Reduction and Oxygen Evolution Reactions
Authors: Patil Indrajit M. , Lokanathan Moorthi , Ganesan Balakrishnan , Swami Anita , Kakade Bhalchandra 
Published: October 2016

AbstractIt is an immense challenge to develop bifunctional electrocatalysts for oxygen reduction reactions (ORR) and oxygen evolution reactions (OER) in low temperature fuel cells and rechargeable metal–air batteries. Herein, a simple and cost‐effective approach is developed to prepare novel materials based on carbon nanotubes (CNTs) and a hexagonal boron nitride (h‐BN) nanocomposite (CNT/BN) through a one‐step hydrothermal method. The structural analysis and morphology study confirms the formation of a homogeneous composite and merging of few exfoliated graphene layers of CNTs on the graphitic planes of h‐BN, respectively. Moreover, the electrochemical study implies that CNT/BN nanocomposite shows a significantly higher ORR activity with a single step 4‐electron transfer pathway and an improved onset potential of +0.86 V versus RHE and a current density of 5.78 mA cm−2 in alkaline conditions. Interestingly, it exhibits appreciably better catalytic activity towards OER at low overpotential (η=0.38 V) under similar conditions. Moreover, this bifunctional catalyst shows substantially higher stability than a commercial Pt/C catalyst even after 5000 cycles. Additionally, this composite catalyst does not show any methanol oxidation reactions that nullify the issues due to fuel cross‐over effects in direct methanol fuel cell applications.
Twisted Polycyclic Arenes from Tetranaphthyldiphenylbenzenes by Controlling the Scholl Reaction with Substituents
Authors: Yang Yong , Yuan Luyan , Shan Bowen , Liu Zhifeng , Miao Qian 
Published: October 2016

AbstractHerein, we report two new types of twisted polycyclic arenes (2 a, b and 3 a, b) with constitutionally isomeric π‐backbones, which are synthesized by controlling the Scholl reaction of 1,2,4,5‐tetra(naphth‐2‐yl)‐3,6‐diphenylbenzene (1) with properly positioned electron‐donating substituents. With a polycyclic backbone containing two [5]helicene and four [4]helicene moieties, 2 a and b are new members of multiple helicenes with interesting stereochemistries. The as‐synthesized 2 a and b are the twisted isomers, and thermal isomerization of twisted‐2 b results in anti‐2 b, a more stable stereoisomer. Both twisted‐ and anti‐2 b have been fully characterized, and the thermal isomerization of twisted‐2 b has been studied with 1H NMR spectroscopy and DFT calculations. Compounds 3 a and b are new members of twistacenes, the benzannulated pentacene backbone of which exhibits an end‐to‐end twist as found from the crystal structure. Twisted‐ and anti‐2 b are also found to function as p‐type semiconductors in solution‐processed thin film transistors, whereas the thin films of 3 b appear insulating presumably due to the lack of π–π interactions.
Analysis for effects of electrolyte level on energy consumption in magnesium electrolysis by finite element method
Authors: Sun Ze , Cai Liwei , Liu Chenglin , Lu Guimin , Yu Jianguo 
Published: October 2016

ABSTRACTIn the process of magnesium electrolysis, increasing the level of electrolyte can reduce the cell voltage and energy consumption in an electrolysis magnesium cell. In this paper, a three‐dimensional model of a full cell was implemented to study the relationship between the cell voltage and electrolyte level in a magnesium electrolysis cell. Firstly, the resistance voltage of difference current intensity in magnesium electrolysis cells were discussed with the electrolyte depth from 1.25 to 1.45 m. Moreover, the size of anodes and positions of anodes and cathodes were changed to investigate the trend of resistance voltage in the cell. The energy consumption in each part of the electrolyte was integrated to further understand the energy distribution in the electrolyte to explore which part of the electrolyte has the greatest contribution to the cell voltage. Through analyzing components of the cell voltage, energy distribution, and thermal balance, the explanation of the relationship between electrolyte level and energy consumption can be obtained.
PEN: a power law–enhanced network design for high efficiency multicore architecture
Authors: Xu Thomas Canhao , Leppänen Ville 
Published: October 2016

SummaryWe propose a heterogeneous on‐chip interconnection aiming at high efficiency multicore processors. An ideal on‐chip interconnection should have low latency, high throughput, low power consumption, and high scalability. However, these metrics are usually contradictory with each other. Besides, a design should focus on the requirements of real applications. We investigate the characteristics of several parallel applications. It is found that the distribution of traffic is similar as the power law. We also discovered hot spot traffic, as well as bursty traffic from applications. Meanwhile, the average injection rate of parallel applications is relatively low. The proposed network is based on a dual‐net concentrated mesh, where 2 physical networks are implemented for processing different messages and improve throughput. A diagonal interconnection is used in the central part of the network for alleviating the traffic hot spot without significant hardware overhead. We evaluate the proposed design with synthetic traffic and real applications by using a simulator. Results indicate that, on average for 8 applications, the network latency of the proposed design has reduced by 32% compared with regular mesh. Concerning efficiency when executing applications, the average energy delay product of the proposed design is 52.7% and 29.7% better than mesh and concentrate mesh, respectively.
Genetic‐Algorithm‐Based Optimization of a Peptidic Scaffold for Sequestration and Hydration of CO2
Authors: Brunk Elizabeth , Perez Marta A. S. , Athri Prashanth , Rothlisberger Ursula 
Published: October 2016

AbstractBiomimicry is a strategy that makes practical use of evolution to find efficient and sustainable ways to produce chemical compounds or engineer products. Exploring the natural machinery of enzymes for the production of desired compounds is a highly profitable investment, but the design of efficient biomimetic systems remains a considerable challenge. An ideal biomimetic system self‐assembles in solution, binds a desired range of substrates and catalyzes reactions with turnover rates similar to the native system. To this end, tailoring catalytic functionality in engineered peptides generally requires site‐directed mutagenesis or the insertion of additional amino acids, which entails an intensive search across chemical and sequence space. Here we discuss a novel strategy for the computational design of biomimetic compounds and processes that consists of a) characterization of the wild‐type and biomimetic systems; b) identification of key descriptors for optimization; c) an efficient search through sequence and chemical space to tailor the catalytic capabilities of the biomimetic system. Through this proof‐of‐principle study, we are able to decisively understand and identify whether a given scaffold is useful, appropriate and tailorable for a given, desired task.
Comparison of fiducial marker detection and object interaction in activities of daily living utilising a wearable vision sensor
Authors: Shewell C. , Medina‐Quero J. , Espinilla M. , Nugent C. , Donnelly M. , Wang H. 
Published: October 2016

SummaryThis paper presents a comparison between algorithms (Oriented FAST and Rotated BRIEF (ORB) and Aruco) for the detection of fiducial markers placed throughout a smart environment. A series of activities of daily living (ADL) were conducted while monitoring a first‐person perspective of the situation; this was achieved through the usage of the Google Glass platform. Fiducial markers were employed, as a means to assist with the detection of specific objects of interest, within the environment. Each marker was assigned unique Identification (ID) and was used to identify the object. Three activities were performed by a participant within the environment. On subsequent trials of the solution, lighting conditions were modified to assess fiducial marker detection rates on a frame‐by‐frame basis. This paper presents the results from this investigation, detailing performance measure for each object detected under various lighting conditions, motion blur and distance from the objects. An intelligent system was developed to specifically consider distance estimation in order to aid with the filtering out of false interactions. A linear filtering method was applied along with a fuzzy membership function to estimate the degree of user interaction, which assists in removing false positives generated by the occupant. The intelligent system returns an average precision, recall and an F‐Measure of 0.99, 0.62 and 0.49, respectively. Copyright © 2016 John Wiley & Sons, Ltd.
Arbuscular mycorrhizal fungi negatively affect soil seed bank viability
Authors: Maighal Mahmood , Salem Mohamed , Kohler Josef , Rillig Matthias C. 
Published: October 2016

AbstractSeed banks represent a reservoir of propagules important for understanding plant population dynamics. Seed viability in soil depends on soil abiotic conditions, seed species, and soil biota. Compared to the vast amount of data on plant growth effects, next to nothing is known about how arbuscular mycorrhizal fungi (AMF) could influence viability of seeds in the soil seed bank. To test whether AMF could influence seed bank viability, we conducted three two‐factorial experiments using seeds of three herbaceous plant species (Taraxacum officinale, Dactylis glomerata, and Centaurea nigra) under mesocosm (experiments 1 and 2) and field conditions (experiment 3) and modifying the factor AMF presence (yes and no). To allow only hyphae to grow in and to prevent root penetration, paired root exclusion compartments (RECs) were used in experiments 2 and 3, which were either rotated (interrupted mycelium connection) or kept static (allows mycorrhizal connection). After harvesting, seed viability, soil water content, soil phosphorus availability, soil pH, and hyphal length in RECs were measured. In experiment 1, we used inoculation or not with the AMF Rhizophagus irregularis to establish the mycorrhizal treatment levels. A significant negative effect of mycorrhizal hyphae on viability of seeds was observed in experiments 1 and 3, and a similar trend in experiment 2. All three experiments showed that water content, soil pH, and AMF extraradical hyphal lengths were increased in the presence of AMF, but available P was decreased significantly. Viability of seeds in the soil seed bank correlated negatively with water content, soil pH, and AMF extraradical hyphal lengths and positively with soil P availability. Our results suggest that AMF can have a negative impact on soil seed viability, which is in contrast to the often‐documented positive effects on plant growth. Such effects must now be included in our conceptual models of the AM symbiosis.
Sequencing improves our ability to study threatened migratory species: Genetic population assignment in California's Central Valley Chinook salmon
Authors: Meek Mariah H. , Baerwald Melinda R. , Stephens Molly R. , Goodbla Alisha , Miller Michael R. , Tomalty Katharine M. H. , May Bernie 
Published: October 2016

AbstractEffective conservation and management of migratory species requires accurate identification of unique populations, even as they mix along their migratory corridors. While telemetry has historically been used to study migratory animal movement and habitat use patterns, genomic tools are emerging as a superior alternative in many ways, allowing large‐scale application at reduced costs. Here, we demonstrate the usefulness of genomic resources for identifying single‐nucleotide polymorphisms (SNPs) that allow fast and accurate identification of the imperiled Chinook salmon in the Great Central Valley of California. We show that 80 well‐chosen loci, drawn from a pool of over 11,500SNPs developed from restriction site‐associatedDNAsequencing, can accurately identify Chinook salmon runs and select populations within run. No otherSNPpanel for Central Valley Chinook salmon has been able to achieve the high accuracy of assignment we show here. This panel will greatly improve our ability to study and manage this ecologically, economically, and socially important species and demonstrates the great utility of using genomics to study migratory species.