bluuebunny/crossref_metadata_2025_split huggingface dataset:
De‐novo‐3D‐Strukturaufklärung mit Proteinmengen unter einem Milligramm mittels 100‐kHz‐MAS‐Festkörper‐NMR‐Spektroskopie
Authors: Agarwal Vipin , Penzel Susanne , Szekely Kathrin , Cadalbert Riccardo , Testori Emilie , Oss Andres , Past Jaan , Samoson Ago , Ernst Matthias , Böckmann Anja , Meier Beat H. 
Published: September 2014

AbstractDie Festkörper‐NMR‐Spektroskopie gewinnt zunehmend an Bedeutung, wenn es um Strukturuntersuchungen von kristallinen, sich in Membranen befindlichen, sedimentierten oder fibrillären Proteinen geht. Bei vielen Untersuchungen werden allerdings typischerweise mehrere isotopenmarkierte Proben von 10–20 mg gebraucht. Wir zeigen hier, dass mit einem neuen NMR‐Probenkopf, der Rotationsfrequenzen um den magischen Winkel um 100 kHz erreicht, die Linienbreiten der Protonensignale verkleinert werden können. Unter ausschließlicher Verwendung von Strukturinformationen aus so gewonnenen Daten wurde eine gut definierte De‐novo‐Struktur des Modellproteins Ubiquitin mit zwei Proben zu je etwa 500 μg Protein erhalten. Damit ergeben sich neue Möglichkeiten für die Strukturbestimmung von Proteinen, die nur im Mikrogramm‐ oder zweistelligen Nanogrammbereich verfügbar sind. Dies sind typische Mengen für zum Beispiel eukaryotische Membranproteine, die in Organismen oder zellfrei exprimiert werden.
Colloidal Self‐Assembly of Catalytic Copper Nanoclusters into Ultrathin Ribbons
Authors: Wu Zhennan , Li Yanchun , Liu Jiale , Lu Zhongyuan , Zhang Hao , Yang Bai 
Published: September 2014

AbstractMetal nanoclusters (NCs) with diameter below 2 nm are promising catalysts in oxygen reduction reactions (ORR). However, the high surface energy of ultra‐small clusters leads to structural instability, shedding doubt on practical applications. Herein, we demonstrate a self‐assembly method to improve the durability of catalytic metal NCs, employing copper NCs capped by 1‐dodecanethiol (DT) to form free‐standing ribbons in colloidal solution. By tuning the cooperation between the dipolar attraction between Cu NCs and the van der Waals attraction between DT, the thickness of ribbons is adjusted to a single NC scale. Such free‐standing ribbons exhibit excellent catalytic activity and durability in ORR.
Reaktionen in Nitroimidazol, ausgelöst durch niederenergetische (0–2 eV) Elektronen: Methylierung an N1‐H blockiert die Reaktivität
Authors: Tanzer Katrin , Feketeová Linda , Puschnigg Benjamin , Scheier Paul , Illenberger Eugen , Denifl Stephan 
Published: September 2014

AbstractNiederenergetische Elektronen (NEEs) mit Energien unter 2 eV zersetzen 4‐Nitroimidazol (4NI) sehr effizient über dissoziative Elektronenanlagerung (DEA). Diese Reaktionen umfassen einfache Bindungsbrüche, aber auch komplexere Prozesse wie mehrfache Bindungsbrüche und die Bildung neuer Moleküle. Alle diese Reaktionen zeigen sich als scharfe Strukturen im detektierten Anionensignal und werden als Feshbach‐Resonanzen gedeutet, die effiziente Wegbereiter für DEA sind. Die außergewöhnlich vielfältigen chemischen Reaktionen von 4NI werden bei Methylierung von 4NI an der N1‐Position komplett blockiert. Diese bemerkenswerten Resultate haben auch Auswirkung auf die Entwicklung von Radiosensibilisatoren für die Strahlungstherapie von Tumoren auf Basis von Nitroimidazol.
Isomere des Dischwefeldinitrids, S2N2
Authors: Zeng Xiaoqing , Flores Antognini Andrea , Beckers Helmut , Willner Helge 
Published: September 2014

AbstractDie UV‐Photolyse (λ=248 oder 255 nm) von cyclischem S2N2, das in fester Argonmatrix isoliert wurde, ergibt zwei offenschalige S2N2‐Isomere, trans‐SNSN (3A′′) und cis‐SNSN (3A′′), sowie das geschlossenschalige C2v‐symmetrische Dimer (SN)2 (1A1). Die neuartigen Isomere wurden über ihre IR‐Spektren und ihre wechselseitige photolytische Umwandlung charakterisiert. Quantenchemische Rechnungen stützen die experimentellen Ergebnisse und bieten Einblicke in die komplexe Potentialhyperfläche von S2N2.
Catalytic Consequences of the Thermodynamic Activities at Metal Cluster Surfaces and Their Periodic Reactivity Trend for Methanol Oxidation
Authors: Tu Weifeng , Chin Ya‐Huei (Cathy) 
Published: September 2014

AbstractThe periodic reactivity trend and the connection of kinetics to the thermodynamic activity of oxygen are established for the oxidation of methanol on metal clusters. First‐order rate coefficients are a single‐valued function of the O2‐to‐CH3OH ratio, because this ratio, together with the rate constants for O2 and CH3OH activation, determine the oxygen chemical potential, thus the relative abundance of active sites and bulk chemical state of the clusters. CH3OH activation rate constants on oxygen‐covered Ag, Pt, and Pd and on RuO2 clusters vary with the metal–oxygen binding strength in a classical volcano‐type relation, because the oxygen‐binding strength directly influences the reactivities of oxygen as H abstractors during the kinetically relevant CH3OH activation step. The differences in oxygen thermodynamic activity lead to five orders of magnitude variation in rates (Pt>Pd>RuO2>Ag, 373 K), because of its strong effects on the activation enthalpy and more prominently activation entropy in CH3OH activation.
Role of fluorinated monomer for simple demolding in nanoimprint lithography
Authors: Shin Min Jae , Shin Young Jae , Shin Jae Sup 
Published: September 2014

ABSTRACTIn this study, we explored the effect of a fluorinated monomer on nanoimprint lithography (NIL) and determined the optimum amount of fluorinated monomer required in the formulation for better NIL. To estimate the role of the fluorinated monomer for demolding, NIL was conducted using copolymers of nonfluorinated silane monomers and fluorinated silane monomers. Epoxy ring‐opening photopolymerization based on the cationic polymerization mechanism was utilized for the NIL process. The physical properties of the photopolymerized copolymeric materials, such as tensile strength, elongation, modulus, and impact strength, as well as surface characteristics such as the contact angle were reported. Aluminum deposition on the nanoimprinted pattern, which is instrumental in fabricating a wire grid polarizer, was also conducted. According to the study results, the use of a copolymer containing 20 mol % of the fluorinated monomer in NIL proved to be the best formulation for easy demolding and for ensuring optimum levels of the physical properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41317.
Preceramic polymer as precursor for near‐stoichiometric silicon carbon with high ceramic yield
Authors: Qian Xi , Zhou Quan , Ni LiZhong 
Published: September 2014

ABSTRACTPrecursor polycarbosilane containing acetylenic and SiH group (PCAS) has been successfully prepared by the reaction of dilithioacetylene with methyl dichlorosilane, and characterized by gel permeation chromatography, Fourier transform infrared spectroscopy, 1H‐NMR, 13C‐NMR, and 29Si‐NMR. Thermogravimetric analysis curve in nitrogen showed the temperature of 5 wt % weight losses (Td5) was 613°C, while the ceramic yield of PCAS was 88% at 1000°C. Pyrolysis behavior and structure evolution of the cured PCAS were studied by means of X‐ray diffraction, Raman, scanning electron microscope‐energy dispersive X‐ray spectrometer, transmission electron microscope (selected area electron diffraction and high resolution transmission electron microscope), and elemental analysis. The polymer to ceramic conversion was completed at 1600°C and the results revealed that the ceramic consisted of β‐SiC and α‐SiC. The composition of the ceramic was near‐stoichiometric with molar ratio of Si/C (1.02 : 1) except rare and localized free carbon inclusions. The SiC ceramics exhibited high thermo‐oxidation resistance at elevated temperatures in air atmosphere. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41335.
Real‐time property prediction for an industrial rubber‐mixing process with probabilistic ensemble Gaussian process regression models
Authors: Liu Yi , Gao Zengliang 
Published: September 2014

ABSTRACTIn internal rubber‐mixing processes, data‐driven soft sensors have become increasingly important for providing online measurements for the Mooney viscosity information. Nevertheless, the prediction uncertainty of the model has rarely been explored. Additionally, traditional viscosity prediction models are based on single models and, thus, may not be appropriate for complex processes with multiple recipes and shifting operating conditions. To address both problems simultaneously, we propose a new ensemble Gaussian process regression (EGPR)‐based modeling method. First, several local Gaussian process regression (GPR) models were built with the training samples in each subclass. Then, the prediction uncertainty was adopted to evaluate the probabilistic relationship between the new test sample and several local GPR models. Moreover, the prediction value and the prediction variance was generated automatically with Bayesian inference. The prediction results in an industrial rubber‐mixing process show the superiority of EGPR in terms of prediction accuracy and reliability. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41432.
Comparison of tensile and compressive characteristics of intra/interply hybrid laminates reinforced high‐density flexible foam composites
Authors: Yan Ruosi , Wang Rui , Lou Ching‐Wen , Lin Jia‐Horng 
Published: September 2014

ABSTRACTThe current study focused on fabrication and mechanical evaluation of intra/interply hybrid laminates–reinforced high‐density flexible foam composites. The effects of composite thickness and expansion factor on the tensile and compressive characterization of the hybrid‐laminated composites were experimentally investigated. Double face sheets were made of high‐strength intra/interply hybrid laminates containing recycled Kevlar nonwovens and glass woven fabric. The results revealed that the hybrid laminates face sheet apparently promoted the tensile strength and tear resistance of the high‐density flexible polyurethane foam. Tearing resistance in perpendicular direction exceeded more than twice the value in parallel direction. In terms of dynamic cushioning properties, cushioning force increased with the increase in composite thickness and the decrease in expansion factor, whereas the cushioning capacity loss, however, showed a different trend with the variation of the parameters. Most samples buffered more than 95% incident force under dynamic loading. Composite thickness and expansion factor exhibited significant influence on compression and indentation properties, including hardness, initial hardness factor, and indentation modulus. Except the composites with 10 mm thickness, the intra/interply hybrid laminated composites exhibited hysteresis loss of indentation force deflection ranging from approximately 30 to 38%, which was due to the fiber and thermal bonding point failure of hybrid laminates as unrecoverable damage. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41438.
Altered Functional Magnetic Resonance Imaging Responses to Nonpainful Sensory Stimulation in Fibromyalgia Patients
Authors: López‐Solà Marina , Pujol Jesus , Wager Tor D. , Garcia‐Fontanals Alba , Blanco‐Hinojo Laura , Garcia‐Blanco Susana , Poca‐Dias Violant , Harrison Ben J. , Contreras‐Rodríguez Oren , Monfort Jordi , Garcia‐Fructuoso Ferran , Deus Joan 
Published: September 2014

ObjectiveFibromyalgia (FM) is a disorder characterized by chronic pain and enhanced responses to acute noxious events. However, the sensory systems affected in FM may extend beyond pain itself, as FM patients show reduced tolerance to non‐nociceptive sensory stimulation. Characterizing the neural substrates of multisensory hypersensitivity in FM may thus provide important clues about the underlying pathophysiology of the disorder. The aim of this study was to characterize brain responses to non‐nociceptive sensory stimulation in FM patients and their relationship to subjective sensory sensitivity and clinical pain severity.MethodsFunctional magnetic resonance imaging (MRI) was used to assess brain response to auditory, visual, and tactile motor stimulation in 35 women with FM and 25 matched controls. Correlation and mediation analyses were performed to establish the relationship between brain responses and 3 types of outcomes: subjective hypersensitivity to daily sensory stimulation, spontaneous pain, and functional disability.ResultsPatients reported increased subjective sensitivity (increased unpleasantness) in response to multisensory stimulation in daily life. Functional MRI revealed that patients showed reduced task‐evoked activation in primary/secondary visual and auditory areas and augmented responses in the insula and anterior lingual gyrus. Reduced responses in visual and auditory areas were correlated with subjective sensory hypersensitivity and clinical severity measures.ConclusionFM patients showed strong attenuation of brain responses to nonpainful events in early sensory cortices, accompanied by an amplified response at later stages of sensory integration in the insula. These abnormalities are associated with core FM symptoms, suggesting that they may be part of the pathophysiology of the disease.
Altered Cellular and Humoral Immunity to Varicella‐Zoster Virus in Patients With Autoimmune Diseases
Authors: Rondaan Christien , de Haan Aalzen , Horst Gerda , Hempel J. Cordelia , van Leer Coretta , Bos Nicolaas A. , van Assen Sander , Bijl Marc , Westra Johanna 
Published: September 2014

ObjectivePatients with autoimmune diseases such as systemic lupus erythematosus (SLE) and granulomatosis with polyangiitis (Wegener's) (GPA) have a 3–20‐fold increased risk of herpes zoster compared to the general population. The aim of this study was to evaluate if susceptibility is due to decreased levels of cellular and/or humoral immunity to the varicella‐zoster virus (VZV).MethodsA cross‐sectional study of VZV‐specific immunity was performed in 38 SLE patients, 33 GPA patients, and 51 healthy controls. Levels of IgG and IgM antibodies to VZV were measured using an in‐house glycoprotein enzyme‐linked immunosorbent assay (ELISA). Cellular responses to VZV were determined by interferon‐γ (IFNγ) enzyme‐linked immunospot (ELISpot) assay and carboxyfluorescein succinimidyl ester (CFSE) dye dilution proliferation assay.ResultsLevels of IgG antibodies to VZV were increased in SLE patients as compared to healthy controls, but levels of IgM antibodies to VZV were not. Antibody levels in GPA patients did not differ significantly from levels in healthy controls. In response to stimulation with VZV, decreased numbers of IFNγ spot‐forming cells were found among SLE patients (although not GPA patients) as compared to healthy controls. Proliferation of CD4+ T cells in response to stimulation with VZV was decreased in SLE patients but not GPA patients.ConclusionSLE patients have increased levels of IgG antibodies against VZV, while cellular immunity is decreased. In GPA patients, antibody levels as well as cellular responses to VZV were comparable to those in healthy controls. These data suggest that increased prevalence of herpes zoster in SLE patients is due to a poor cellular response. Vaccination strategies should aim to boost cellular immunity against VZV.
Major Histocompatibility Complex Class I and Class II Alleles May Confer Susceptibility to or Protection Against Morphea: Findings From the Morphea in Adults and Children Cohort
Authors: Jacobe Heidi , Ahn Chul , Arnett Frank C. , Reveille John D. 
Published: September 2014

ObjectiveTo determine the HLA class I and class II alleles of the human major histocompatibility complex showing an association with morphea (localized scleroderma) in the Morphea in Adults and Children (MAC) cohort, using a nested case–control association study.MethodsPatients with morphea were identified from the MAC cohort, and matched controls were obtained from the National Institutes of Health/National Institute of Arthritis and Musculoskeletal and Skin Diseases Scleroderma Family Registry and DNA Repository and from the Division of Rheumatology at the University of Texas Health Science Center at Houston. HLA class II genotyping and single‐strand conformational polymorphism typing were performed to identify HLA–A, B, and C alleles. Associations between HLA class I and class II alleles and morphea, as well as its subphenotypes, were determined.ResultsTwo hundred eleven patients with morphea and 726 matched controls were available for HLA class I typing, and 158 patients with morphea and 1,008 matched controls were available for HLA class II typing. The strongest associations were found with DRB1*04:04 (odds ratio [OR] 2.3, 95% confidence interval [95% CI] 1.4–4.0, P = 0.002), and HLA–B*37 conferred the highest OR among the class I alleles (OR 3.2, 95% CI 1.5–6.5, P = 0.001). Comparison of the risk allele profile in this cohort with the risk alleles previously identified in patients with systemic sclerosis, determined using the same methods and same control population, revealed one allele in common, DRB*04:04.ConclusionThese results demonstrate that specific HLA class I and class II alleles are associated with morphea and are also likely to be associated with generalized and linear subtypes of morphea. The morphea‐associated alleles are different from those found in scleroderma, suggesting that morphea is immunogenetically distinct. Risk alleles in morphea are also associated with conditions such as rheumatoid arthritis (RA) and other autoimmune conditions. Population‐based studies have indicated that patients with RA have an increased risk of morphea, and therefore a common susceptibility allele may be implicated.
Effects of Fostamatinib, an Oral Spleen Tyrosine Kinase Inhibitor, in Rheumatoid Arthritis Patients With an Inadequate Response to Methotrexate: Results From a Phase III, Multicenter, Randomized, Double‐Blind, Placebo‐Controlled, Parallel‐Group Study
Authors: Weinblatt Michael E. , Genovese Mark C. , Ho Meilien , Hollis Sally , Rosiak‐Jedrychowicz Krystyna , Kavanaugh Arthur , Millson David S. , Leon Gustavo , Wang Millie , van der Heijde Désirée 
Published: September 2014

ObjectiveThis phase III, 52‐week study compared fostamatinib with placebo (for 24 weeks) in patients with active rheumatoid arthritis (RA) and an inadequate response to methotrexate (MTX) therapy.MethodsPatients taking MTX were randomized (1:1:1) to receive fostamatinib 100 mg twice daily for 52 weeks (group A), fostamatinib 100 mg twice daily for 4 weeks and then 150 mg once daily (group B), or placebo for 24 weeks and then fostamatinib 100 mg twice daily (group C). At week 24, the co–primary end points were change from baseline in the American College of Rheumatology 20% (ACR20) improvement response rates and change in the modified total Sharp/van der Heijde score of radiographic damage (SHS).ResultsIn this study, 918 patients were randomized and received ≥1 dose of study drug (fostamatinib or placebo); the demographic and baseline clinical characteristics were well balanced. Following treatment with both fostamatinib regimens, a statistically significant difference in the ACR20 improvement response was achieved at week 24 as compared with that in patients receiving placebo (49.0% [group A] and 44.4%, [group B] versus 34.2%; P < 0.001 and P = 0.006, respectively), but there was no statistically significant difference in the SHS between either fostamatinib group and placebo (P = 0.25 and P = 0.17, respectively). The most common adverse events in patients in groups A, B, and C were hypertension (15.8%, 15.1%, and 3.9%, respectively) and diarrhea (13.9%, 15.1%, and 3.9%, respectively). Elevated blood pressure (≥140/90 mm Hg) occurred at ≥1 visit in 44.2%, 41.6%, and 19.3% of patients in each respective group.ConclusionWith the use of either fostamatinib regimen in patients with RA, statistically significant, but not clinically significant, improvements in the ACR20 improvement response over placebo were achieved at 24 weeks, whereas a significant difference in the SHS was not seen. The overall level of response to treatment with fostamatinib was lower than had been observed in the phase II program, but similar adverse events were reported.
Electrospun Cu/Sn/C Nanocomposite Fiber Anodes with Superior Usable Lifetime for Lithium‐ and Sodium‐Ion Batteries
Authors: Kim Jae‐Chan , Kim Dong‐Wan 
Published: September 2014

AbstractCu/Sn/C composite nanofibers were synthesized by using dual‐nozzle electrospinning and subsequent carbonization. The composite nanofibers are a homogeneous amorphous matrix comprised of Cu, Sn, and C with a trace of crystalline Sn. The Li‐ and Na‐ion storage performance of the Cu/Sn/C fiber electrodes were investigated by using cyclic voltammetry, galvanostatic cycling, and electrochemical impedance spectroscopy. Excellent, stable cycling performance indicates capacities of 490 and 220 mA h g−1 for Li‐ion (600 cycles) and Na‐ion (200 cycles) batteries, respectively. This is a significant improvement over other reported Sn/C nanocomposite devices. These superior electrochemical properties could be attributed to the advantages of incorporating one‐dimensional nanostructures into the electrodes, such as short electron diffusion lengths, large specific surface areas, ideal homogeneous structures for buffering volume changes, and better electronic conductivity that results from the amorphous copper and carbon matrix.
Characterization of apoptosis in PER.C6® batch and perfusion cultures
Authors: Mercier Sarah M. , Diepenbroek Bas , Martens Dirk , Wijffels Rene H. , Streefland Mathieu 
Published: September 2014

ABSTRACTPreventing or delaying cell death is a challenge in mammalian cell cultures for the development and optimization of production processes for biopharmaceuticals. Cell cultures need to be maintained highly viable for extended times in order to reach maximum production yields. Moreover, programmed cell death through apoptosis is often believed to occur without being detected by classical viability measurements. In this study, we characterized cell death in PER.C6® batch and perfusion cultures using three flow cytometry techniques measuring different steps of the apoptosis cascade: DNA fragmentation, caspases activation and phosphatidylserine externalization. We showed that apoptosis is the main pathway of PER.C6® cell death in batch cultures after depletion of main carbon sources. In high cell density perfusion cultures fed at a constant specific perfusion rate, both high viability and very limited apoptosis were observed. When extending this perfusion process far beyond standard operations, cultures were exposed to suboptimal process conditions, which resulted in an increase of apoptotic cell death. Moreover, we showed that the reference viability measurement using trypan blue exclusion properly assesses the level of cell death in PER.C6® cultures. This study is a first step in understanding the mechanisms of PER.C6® cell death, which will be helpful to support applications of the cell line. Biotechnol. Bioeng. 2015;112: 569–578. © 2014 Wiley Periodicals, Inc.