bluuebunny/crossref_metadata_2025_split huggingface dataset:
An S‐Oxygenated [NiFe] Complex Modelling Sulfenate Intermediates of an O2‐Tolerant Hydrogenase
Authors: Lindenmaier Nils J. , Wahlefeld Stefan , Bill Eckhard , Szilvási Tibor , Eberle Christopher , Yao Shenglai , Hildebrandt Peter , Horch Marius , Zebger Ingo , Driess Matthias 
Published: January 2017

AbstractTo understand the molecular details of O2‐tolerant hydrogen cycling by a soluble NAD+‐reducing [NiFe] hydrogenase, we herein present the first bioinspired heterobimetallic S‐oxygenated [NiFe] complex as a structural and vibrational spectroscopic model for the oxygen‐inhibited [NiFe] active site. This compound and its non‐S‐oxygenated congener were fully characterized, and their electronic structures were elucidated in a combined experimental and theoretical study with emphasis on the bridging sulfenato moiety. Based on the vibrational spectroscopic properties of these complexes, we also propose novel strategies for exploring S‐oxygenated intermediates in hydrogenases and similar enzymes.
Removal of Multiple Contaminants from Water by Polyoxometalate Supported Ionic Liquid Phases (POM‐SILPs)
Authors: Herrmann Sven , De Matteis Laura , de la Fuente Jesús M. , Mitchell Scott G. , Streb Carsten 
Published: January 2017

AbstractThe simultaneous removal of organic, inorganic, and microbial contaminants from water by one material offers significant advantages when fast, facile, and robust water purification is required. Herein, we present a supported ionic liquid phase (SILP) composite where each component targets a specific type of water contaminant: a polyoxometalate‐ionic liquid (POM‐IL) is immobilized on porous silica, giving the heterogeneous SILP. The water‐insoluble POM‐IL is composed of antimicrobial alkylammonium cations and lacunary polyoxometalate anions with heavy‐metal binding sites. The lipophilicity of the POM‐IL enables adsorption of organic contaminants. The silica support can bind radionuclides. Using the POM‐SILP in filtration columns enables one‐step multi‐contaminant water purification. The results show how multi‐functional POM‐SILPs can be designed for advanced purification applications.
Determining Electrochemical Surface Stress of Single Nanowires
Authors: Wang Hui , Shan Xiaonan , Yu Hui , Wang Yan , Schmickler Wolfgang , Chen Hong‐Yuan , Tao Nongjian 
Published: January 2017

AbstractElectrochemical surface stress is important in nanomaterials because of their large surface‐to‐volume ratios, which lead to unique mechanical and electrocatalytic properties, but directly measuring this quantity has been challenging. Here we report on experimental determination of the surface stress, and associated electrochemical processes of a single gold nanowire with an optical imaging technique. We show that surface stress changes linearly and reversibly with the potential between 0 and 0.8 V versus Ag/AgCl, but abruptly with large hysteresis, associated with the oxidation and reduction of the nanowire, between 0.8 and 1.5 V. The potential derivative of the surface stress closely resembles the cyclic voltammograms. We described the observations in terms of anion adsorption and surface oxidation/reduction. This work demonstrates a new approach to study electrochemical processes and the associated surface stress changes of nanomaterials.
Mononuclear Clusterfullerene Single‐Molecule Magnet Containing Strained Fused‐Pentagons Stabilized by a Nearly Linear Metal Cyanide Cluster
Authors: Liu Fupin , Wang Song , Gao Cong‐Li , Deng Qingming , Zhu Xianjun , Kostanyan Aram , Westerström Rasmus , Jin Fei , Xie Su‐Yuan , Popov Alexey A. , Greber Thomas , Yang Shangfeng 
Published: January 2017

AbstractFused‐pentagons results in an increase of local steric strain according to the isolated pentagon rule (IPR), and for all reported non‐IPR clusterfullerenes multiple (two or three) metals are required to stabilize the strained fused‐pentagons, making it difficult to access the single‐atom properties. Herein, we report the syntheses and isolations of novel non‐IPR mononuclear clusterfullerenes MNC@C76 (M=Tb, Y), in which one pair of strained fused‐pentagon is stabilized by a mononuclear cluster. The molecular structures of MNC@C76 (M=Tb, Y) were determined unambiguously by single‐crystal X‐ray diffraction, featuring a non‐IPR C2v(19138)‐C76 cage entrapping a nearly linear MNC cluster, which is remarkably different from the triangular MNC cluster within the reported analogous clusterfullerenes based on IPR‐obeying C82 cages. The TbNC@C76 molecule is found to be a field‐induced single‐molecule magnet (SMM).
A 11‐Steps Total Synthesis of Magellanine through a Gold(I)‐Catalyzed Dehydro Diels–Alder Reaction
Authors: McGee Philippe , Bétournay Geneviève , Barabé Francis , Barriault Louis 
Published: January 2017

AbstractWe have developed an innovative strategy for the formation of angular carbocycles via a gold(I)‐catalyzed dehydro Diels–Alder reaction. This transformation provides rapid access to a variety of complex angular cores in excellent diastereoselectivities and high yields. The usefulness of this AuI‐catalyzed cycloaddition was further demonstrated by accomplishing a 11‐steps total synthesis of (±)‐magellanine.
Carbon–Carbon Bond Formation in a Weak Ligand Field: Leveraging Open‐Shell First‐Row Transition‐Metal Catalysts
Authors: Chirik Paul J. 
Published: January 2017

AbstractUnique features of earth‐abundant transition‐metal catalysts are reviewed in the context of catalytic carbon–carbon bond‐forming reactions. Aryl‐substituted bis(imino)pyridine iron and cobalt dihalide compounds, when activated with alkyl aluminum reagents, form highly active catalysts for the polymerization of ethylene. Open‐shell iron and cobalt alkyl complexes have been synthesized that serve as single‐component olefin polymerization catalysts. Reduced bis(imino)pyridine iron and cobalt dinitrogen compounds have also been discovered that promote the unique [2+2] cycloaddition of unactivated terminal alkenes. Studies of the electronic structure support open‐shell intermediates, a deviation from traditional strong‐field organometallic compounds that promote catalytic C−C bond formation.
High‐temperature tensile behavior at different crosshead speeds during loading of glass fiber‐reinforced polymer composites
Authors: Mahato Kishore Kumar , Dutta Krishna , Ray Bankim Chandra 
Published: January 2017

ABSTRACTThe present study evaluates on the static tensile behavior of glass fiber reinforced polymer (GFRP) composites at 50% and 70% volume fractions of reinforcement tested at room (25 °C), 70 °C, 90 °C, and 110 °C temperatures with 1, 10, 100, 500, and 1000 mm/min crosshead speeds to investigate the impact of high temperature on the mechanical properties and different dominating failures modes. The experimental results reveal that with increase in crosshead speeds the tensile strength of the composite is increasing. The effect of crosshead speeds and temperature with changing fiber volume fractions affects the GFRP composite. Although both the composite systems are found to be crosshead speed sensitive. Crosshead speed sensitivity seems to be more unpredictable at high temperature and at high crosshead speed. Furthermore, it appears to be more unprecedented nature of fluctuation with high fiber volume fraction. The crucial parameters required during the materials designing in various structural components were evaluated and modelled with the help of Weibull constitutive model. The fractography analyses were done to identify the various dominating failure modes in the GFRP composite. There was no significant change found in the glass transition temperatures (Tg) of both the composite system when exposed to different temperature environments. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44715.
Silver‐ and gold‐labeled colloidal and crosslinked glycopolymers based on glycyl glycosynthons and maleic anhydride copolymers for lectin binding
Authors: Samoilova Nadezhda A. , Krayukhina Maria A. , Babushkina Tatyana A. , Yamskov Igor A. , Likhosherstov Leonid M. , Piskarev Vladimir E. 
Published: January 2017

ABSTRACTA simple, convenient, and inexpensive technique for preparing lectin‐specific nanogold‐ and silver‐labeled colloidal and crosslinked neoglycoconjugates, based on maleic anhydride copolymers, was developed. Water‐soluble nanogold‐ and silver‐labeled glyconanoparticles were obtained in two steps: (1) introduction of free N‐acetyl‐D‐glucosamine or glycyl‐spacered glycosynthons—β‐N‐glycyl‐N‐acetyl‐D‐glucosamine or β‐N‐glycyl‐lactose—into poly(ethylene‐alt‐maleic anhydride) or poly(N‐vinylpyrrolidone‐alt‐maleic anhydride) and (2) labeling in situ the thus‐obtained glycopolymers with gold or silver nanoparticles. Lectin sorbents were synthesized from glycyl‐spacered glycosynthons and spherical, granulated, crosslinked maleic anhydride copolymers in an aqueous system without any condensing agents. Thus, maleic anhydride copolymer was used solely, without any preliminary modification of the polymer, as a matrix for crosslinking, for specific ligand binding, and as metal nanoparticles as a stabilizing cover. The resulting colloidal gold or silver glyconanoparticles were used as lectin sensors (in a dot‐blot analysis of lectins) and as crosslinked neoglycoconjugates for lectin sorption studies. The corresponding gold‐ or silver‐labeled water‐soluble glyconanoparticles and crosslinked neoglycoconjugates manifested high activity and specificity in all tests with a series of β‐D‐GlcNAc‐specific and β‐D‐Gal‐specific lectins. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44718.
Influence of precursor film microstructure on properties of HDPE microporous membranes prepared by stretching
Authors: Yadegari Ali , Morshedian Jalil , Khonakdar Hossein‐Ali , Wagenknecht Udo , Heinrich Gert 
Published: January 2017

ABSTRACTOriented HDPE films having a stacked lamellar morphology were prepared to develop microporous membranes through cast film extrusion followed by stretching. Applying higher draw ratios (DR) and annealing the cast films improved crystal alignments remarkably. It was shown the improvement in c‐axis orientation upon annealing was more significant for the films prepared with lower DR. Furthermore, applying Raman spectroscopy, the amorphous mass fraction of the films was obtained. Subsequently, considering a three‐phase structure (i.e., crystal, amorphous and interphase), the interphase content of the films was also determined. A distinct DR dependence of the interphase content was noticed. It was observed that in addition to crystal perfection upon annealing, the amorphous phase fraction was also decreased due to possibly increase in free volume, promoting lamellar separation and cavitation during the subsequent stretching step. SEM images of the membranes surfaces as well as their normalized water vapor transmission rate (WVTR) values indicated a more uniform pore formation and increased permeability with DR. Furthermore, it was found that lower interphase content in the films with higher DR favors lamellar separation. However, permeability in the stretched precursor films with DR higher than a certain level (DR = 93) was not improved significantly. Moreover, crystallinity and crystal orientation of produced membranes were investigated. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44725.
A Dual Role of Upper Zone of Growth Plate and Cartilage Matrix–Associated Protein in Human and Mouse Osteoarthritic Cartilage: Inhibition of Aggrecanases and Promotion of Bone Turnover
Authors: Stock Michael , Menges Stefanie , Eitzinger Nicole , Geßlein Maria , Botschner Renate , Wormser Laura , Distler Alfiya , Schlötzer‐Schrehardt Ursula , Dietel Katharina , Distler Jörg , Beyer Christian , Gelse Kolja , Engelke Klaus , Koenders Marije I. , van den Berg Wim , von der Mark Klaus , Schett Georg 
Published: January 2017

ObjectiveCartilage damage and subchondral bone changes are closely connected in osteoarthritis. Nevertheless, how these processes are interlinked is, to date, incompletely understood. This study was undertaken to investigate the mechanistic role of a cartilage‐derived protein, upper zone of growth plate and cartilage matrix–associated protein (UCMA), in osteoarthritis‐related cartilage and bone changes.MethodsUCMA expression was assessed in healthy and osteoarthritic human and mouse cartilage. For analysis of cartilage and bone changes, osteoarthritis was induced by destabilization of the medial meniscus (DMM) in wild‐type (WT) and Ucma‐deficient mice. UCMA–collagen interactions, the effect of UCMA on aggrecanase activity, and the impact of recombinant UCMA on osteoclast differentiation were studied in vitro.ResultsUCMA was found to be overexpressed in human and mouse osteoarthritic cartilage. DMM‐triggered cartilage changes, including increased structural damage, proteoglycan loss, and chondrocyte cell death, were aggravated in Ucma‐deficient mice compared to WT littermates, thereby demonstrating the potential chondroprotective effects of UCMA. Moreover, UCMA inhibited ADAMTS‐dependent aggrecanase activity and directly interacted with cartilage‐specific collagen types. In contrast, osteoarthritis‐related bone changes were significantly reduced in Ucma‐deficient mice, showing less pronounced osteophyte formation and subchondral bone sclerosis. Mechanistically, UCMA directly promoted osteoclast differentiation in vitro.ConclusionUCMA appears to link cartilage with bone changes in osteoarthritis by supporting cartilage integrity as an endogenous inhibitor of aggrecanases while also promoting osteoclastogenesis and subchondral bone turnover. Thus, UCMA represents an important link between cartilage and bone in osteoarthritis.
Immune‐Array Analysis in Sporadic Inclusion Body Myositis Reveals HLA–DRB1 Amino Acid Heterogeneity Across the Myositis Spectrum
Authors: Rothwell Simon , Cooper Robert G. , Lundberg Ingrid E. , Gregersen Peter K. , Hanna Michael G. , Machado Pedro M. , Herbert Megan K. , Pruijn Ger J. M. , Lilleker James B. , Roberts Mark , Bowes John , Seldin Michael F. , Vencovsky Jiri , Danko Katalin , Limaye Vidya , Selva‐O'Callaghan Albert , Platt Hazel , Molberg Øyvind , Benveniste Olivier , Radstake Timothy R. D. J. , Doria Andrea , De Bleecker Jan , De Paepe Boel , Gieger Christian , Meitinger Thomas , Winkelmann Juliane , Amos Christopher I. , Ollier William E. , Padyukov Leonid , Lee Annette T. , Lamb Janine A. , Chinoy Hector ,   for the Myositis Genetics Consortium
Published: January 2017

ObjectiveInclusion body myositis (IBM) is characterized by a combination of inflammatory and degenerative changes affecting muscle. While the primary cause of IBM is unknown, genetic factors may influence disease susceptibility. To determine genetic factors contributing to the etiology of IBM, we conducted the largest genetic association study of the disease to date, investigating immune‐related genes using the Immunochip.MethodsA total of 252 Caucasian patients with IBM were recruited from 11 countries through the Myositis Genetics Consortium and compared with 1,008 ethnically matched controls. Classic HLA alleles and amino acids were imputed using SNP2HLA.ResultsThe HLA region was confirmed as the most strongly associated region in IBM (P = 3.58 × 10−33). HLA imputation identified 3 independent associations (with HLA–DRB1*03:01, DRB1*01:01, and DRB1*13:01), although the strongest association was with amino acid positions 26 and 11 of the HLA–DRB1 molecule. No association with anti–cytosolic 5′‐nucleotidase 1A–positive status was found independent of HLA–DRB1*03:01. There was no association of HLA genotypes with age at onset of IBM. Three non‐HLA regions reached suggestive significance, including the chromosome 3 p21.31 region, an established risk locus for autoimmune disease, where a frameshift mutation in CCR5 is thought to be the causal variant.ConclusionThis is the largest, most comprehensive genetic association study to date in IBM. The data confirm that HLA is the most strongly associated region and identifies novel amino acid associations that may explain the risk in this locus. These amino acid associations differentiate IBM from polymyositis and dermatomyositis and may determine properties of the peptide‐binding groove, allowing it to preferentially bind autoantigenic peptides. A novel suggestive association within the chromosome 3 p21.31 region suggests a role for CCR5.
Cocatalyst‐Free Hybrid Ionic Liquid (IL)‐Based Porous Materials for Efficient Synthesis of Cyclic Carbonates through a Cooperative Activation Pathway
Authors: Jayakumar Sanjeevi , Li He , Zhao Yaopeng , Chen Jian , Yang Qihua 
Published: January 2017

AbstractCocatalyst‐free ionic liquid (IL)‐based porous polymers (Px‐Vy‐OHzR) functionalized with an intermolecular hydroxyl group were prepared by means of radical copolymerization of 1‐butyl‐3‐vinylimidazolium bromide, (4‐vinylphenyl)methanol (VBzOH), and divinylbenzene (DVB) under solvothermal conditions. As the ratio of 4‐vinylphenylmethanol in the initial mixture increased, the content of the hydroxyl groups in the polymer increased from 3.35 to 5.35 mmol g−1 and the Brunauer–Emmett–Teller (BET) surface area of the polymer decreased sharply from 365 to 2.5 m2 g−1. In the carbonation of CO2 and epoxides, the turnover frequency (TOF) of Px‐Vy‐OHzR increased gradually from 25 to 67 h−1 as the OH ratio increased irrespective of the sharp decrease in BET surface area, which suggests the existence of a cooperative activation effect between OH and ILs. To obtain a high OH content while still maintaining a high BET surface area, hybrid porous materials (SBA‐[VxOHy]R‐n) were prepared by means of copolymerization of 1‐ethyl‐3‐vinylimidazolium bromide and 4‐vinylphenylmethanol in the mesopores of SBA‐15. SBA‐[VxOHy]R‐n was more active than its polymer counterpart (TOF: 188 versus 71 h−1) in the cycloaddition of CO2 with propyl oxide owing to the combined effect of the high BET surface area and the high OH content. The hybridization of mesoporous materials with polymers represents an efficient strategy for the preparation of high‐performance solid catalysts for chemical transformations.
A General Strategy to Enhance the Performance of Dye‐Sensitized Solar Cells by Incorporating a Light‐Harvesting Dye with a Hydrophobic Polydiacetylene Electrolyte‐Blocking Layer
Authors: Desta Mekonnen Abebayehu , Liao Chia‐Wei , Sun Shih‐Sheng 
Published: January 2017

AbstractA unique strategy to suppress charge recombination effectively and enhance light harvesting in dye‐sensitized solar cells (DSSCs) is demonstrated by the design of a new dipolar organic dye functionalized with a diacetylene unit, which is capable of undergoing a photoinduced crosslinking reaction to generate a hydrophobic polydiacetylene layer. The polydiacetylene layer serves as an electrolyte‐blocking layer that effectively blocks the approach of the oxidized redox mediator and suppresses the dark current, and also plays a role in light harvesting owing to efficient energy transfer to the dipolar dyes. A 15 % efficiency improvement was achieved on going from the monomer dye (JSC=13.5 mA cm−2, Voc=0.728 V, fill factor=0.73, η=7.17 %) to the crosslinked dye (JSC=14.9 mA cm−2, Voc=0.750 V, fill factor=0.74, η=8.27 %) under AM 1.5 conditions.
Nachweis der Ankertragfähigkeit auf Grundlage faseroptischer Messtechnik
Authors: Kindler Arne , Schaller Maria‐Barbara , Glötzl Jürgen 
Published: January 2017

AbstractDie heute gängigen Dauerüberwachungen (Ankermonitoring) von Ankern basieren überwiegend auf dem Einsatz von Ankerkraftmessdosen. Die Erfahrungen der letzten Jahrzehnte haben jedoch gezeigt, dass die Zuverlässigkeit der Anzeige über die Zeit verloren geht. Darüber hinaus bedingt der Einsatz von Ankerkraftmessdosen eine zusätzliche Bauhöhe am Ankerkopf. Andere Mess‐ und Prüfverfahren wie z. B. die herkömmlichen Lichtwellenleitersensoren bedingen einen Abgleich mit einem unbelasteten Lichtwellenleiter und geben nur punktuelle Aussagen über das Tragverhalten wieder. Weiterhin kommt hinzu, dass die gewonnenen Aussagen interpretiert werden müssen, um den Zustand der Verankerung beurteilen zu können. Im folgenden Beitrag wird über erste Ergebnisse eines Ankermonitorings auf der Basis von ortsverteilten Messungen einer in den Verpresskörper eingebetteten Glasfaser berichtet. Das neue Messkonzept basiert auf der Rayleigh‐Technologie und dient der Prüfung des Tragverhaltens des Ankers sowie der Prüfung des Verpresskörperzustands bei betonschädigenden Grundwässern. Aufgrund der Wirtschaftlichkeit der eingesetzten Glasfaser ist die Ausbildung von redundanten Messsystemen nicht mit hohen Kosten verbunden. Hinsichtlich der Langlebigkeit der Glasfasern kann auf Erfahrungen aus der Telekommunikation zurückgegriffen werden.
Associations between pathologic tumor features and preadjuvant therapy cognitive performance in women diagnosed with breast cancer
Authors: Koleck Theresa A. , Bender Catherine M. , Sereika Susan M. , Ryan Christopher M. , Ghotkar Puja , Brufsky Adam M. , Jankowitz Rachel C. , McAuliffe Priscilla F. , Clark Beth Z. , Conley Yvette P. 
Published: January 2017

AbstractIntertumor heterogeneity has been proposed as a potential mechanism to account for variability in cognitive performance in women diagnosed with breast cancer. The purpose of this study was to explore associations between variation in pathologic tumor features (PTFs) and variability in preadjuvant therapy cognitive performance in postmenopausal women newly diagnosed with early‐stage breast cancer. Participants (N = 329) completed a comprehensive battery of neuropsychological tests to evaluate cognitive performance after primary surgery but prior to initiation of adjuvant anastrozole±chemotherapy. PTF data were abstracted from medical records. Robust multiple linear regression models were fit to estimate associations between individual PTFs and the cognitive function composite domain scores. All models controlled for age, estimated intelligence, and levels of depressive symptoms, anxiety, fatigue, and pain. Diagnosis of a HER2‐positive tumor contributed to poorer verbal (b = −0.287, P = 0.018), visual (b = −0.270, P = 0.001), and visual working (b = −0.490, P < 0.001) memory performance compared to diagnosis of a HER2‐negative tumor. Similarly, as HER2 immunohistochemistry classification score increased, verbal (b = −0.072, P = 0.093), visual (b = −0.081, P = 0.003), and visual working (b = −0.170, P < 0.001) memory performance score decreased. Associations with performance were also noted between location, focality/centricity, hormone receptor expression, cellular proliferation (i.e., Ki67), and Oncotype DX® Breast Cancer Assay Recurrence Score®.) Our results suggest that certain PTFs related to more aggressive tumor phenotypes or inferior breast cancer prognosis may be implicated in poorer preadjuvant therapy cognitive performance. Follow‐up studies that include a cognitive assessment before primary surgery should be conducted to further delineate the role of intertumor heterogeneity on cognitive performance.