bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tailoring the Membrane‐Electrode Interface in PEM Fuel Cells: A Review and Perspective on Novel Engineering Approaches
Authors: Breitwieser Matthias , Klingele Matthias , Vierrath Severin , Zengerle Roland , Thiele Simon 
Published: September 2017

AbstractThe interface between the catalyst layer (CL) and the polymer electrolyte membrane (PEM) in a fuel cell has substantial impact on its electrochemical performance. In consequence, there have been growing research activities to engineer this interface to improve the performance of polymer electrolyte membrane fuel cells (PEMFCs). This review summarizes these novel approaches and compares the various techniques. Based on available fuel cell data in the literature, a quantitative comparison of relative improvements due to a micro‐ and nano‐engineered PEM|CL interface is provided. This allows several conclusions: First, regardless of the applied method, a re‐engineering of the PEM|CL interface leads to an improvement of power‐determining parameters, such as mass transport resistances. The latter has hitherto not been clearly connected to the PEM|CL interface and is an important piece of information for future fuel cell development. Second, for patterned membrane surfaces, feature sizes of about 1–10 µm on the membrane surface seem to result in the most significant power density improvement. Third, an engineered PEMCL interface can contribute to extend the fuel cell durability due to enhanced adhesion and contact between the two layers. With this, novel membrane electrode assemblies (MEAs) can be designed that enable significantly higher power densities compared conventional 2D‐layer MEAs.
Durch sichtbares Licht und Nahinfrarotstrahlung abbaubare supramolekulare Metallo‐Gele
Authors: Theis Sabrina , Iturmendi Aitziber , Gorsche Christian , Orthofer Marco , Lunzer Markus , Baudis Stefan , Ovsianikov Aleksandr , Liska Robert , Monkowius Uwe , Teasdale Ian 
Published: September 2017

AbstractDer lichtempfindliche Rutheniumkomplex [Ru(bpy)2(4AMP)2](PF6)2 (4AMP=4‐(Aminomethyl)pyridin) wurde über die reaktiven Aminogruppen der durch Licht abspaltbaren 4AMP‐Liganden in Polyharnstoff‐Organo‐ oder ‐Hydrogele eingebaut. Im Dunkeln sind diese Gele sehr stabil. Durch Bestrahlen mit sichtbarem Licht oder NIR‐Strahlung (letzteres mittels Zweiphotonenabsorption) werden die Ruthenium‐Pyridin‐Bindungen gespalten, was zum Abbau des supramolekularen Gels führt. Dies ermöglicht eine räumlich und zeitlich aufgelöste Mikrostrukturierung des Gels mithilfe einer Photomaske oder eines gepulsten NIR‐Lasers.
Nichtkanonische Basen im Genom: die regulative Informationsebene in der DNA
Authors: Carell Thomas , Kurz Matthias Q. , Müller Markus , Rossa Martin , Spada Fabio 
Published: September 2017

AbstractIn multizellulären Organismen findet man spezialisierte Zellen, die jeweils eine bestimmte Funktion wahrnehmen. Diese zellulären Unterschiede beruhen alle auf der identischen Sequenzinformation, die im Zellkern gespeichert ist. Daher muss diese Sequenzinformation von den verschiedenen Zelltypen unterschiedlich interpretiert werden. Während des frühen Entwicklungsstadiums einer Zelle muss diese Übersetzung räumlich und zeitlich streng kontrolliert werden. Die jeweilige Interpretation der Sequenzinformation umfasst die kontrollierte Aktivierung und Stilllegung spezifischer Gene, sodass ein Protein nur in bestimmten Zellen exprimiert wird. Dafür ist eine weitere Informationsebene vonnöten, die sich von der reinen Basensequenz abhebt. Ein Aspekt dieser regulatorischen Informationsebene beruht auf funktionellen Gruppen an der C5‐Position der kanonischen Base dC. Heute kennt man vier dieser regulatorischen, nichtkanonischen Basen, die eine CH3‐, CH2OH‐, CHO‐ oder COOH‐Gruppe aufweisen. Während 5‐Methylcytidin schon lange als eine der Basen im Genom mit dieser Funktion bekannt ist, wurden die anderen drei Basen – und die für die Entstehung verantwortlichen Enzyme – erst kürzlich entdeckt.
Temperature and pressure effects of drilling fluid on cutting transport using CFD simulations
Authors: Akbari S. , Hashemabadi S. H. 
Published: September 2017

AbstractSimulation of liquid–solid flow in annulus of oil wells is of a great importance to predict the two‐phase flow field in wellbore accurately. In this paper, direct effects of drilling fluid rheological properties by Herschel–Bulkley model on cuttings transportation, pressure drop, and other parameters of two‐phase flow are numerically investigated at different temperatures and pressures. Recent studies have not addressed these effects. Thus, a 3D form of a steady‐state and isothermal model is used to simulate the two‐phase flow in various temperatures and pressures of drilling fluid, flow rates, and drilling pipe rotations. The governing equations created a system of coupled partial differential equations solved using the iterative finite volume method. The comparisons between the results of the model and experimental data and also analytical relation showed that the model can accurately predict two‐phase flow in the annulus. The results indicated that the elevation of temperature and reduction of pressure contributes to a decrease in the cuttings transportation. For drilling fluid velocity of 0.75 m/s, the cuttings transportation has been decreased 2.08% by increasing temperature from 70°C to 90°C in 0.1 MPa, whereas in pressure of 10 MPa, about 1.63% reduction on the transportation of cuttings yielded. © 2017 Curtin University and John Wiley & Sons, Ltd.
A Randomized Phase IIb Study of Mavrilimumab and Golimumab in Rheumatoid Arthritis
Authors: Weinblatt Michael E. , McInnes Iain B. , Kremer Joel M. , Miranda Pedro , Vencovsky Jiri , Guo Xiang , White Wendy I. , Ryan Patricia C. , Godwood Alex , Albulescu Marius , Close David , Burmester Gerd R. 
Published: September 2017

ObjectiveThis 24‐week, phase IIb, double‐blind study was undertaken to evaluate the efficacy and safety of mavrilimumab (a monoclonal antibody to granulocyte–macrophage colony‐stimulating factor receptor α) and golimumab (a monoclonal antibody to tumor necrosis factor [anti‐TNF]) in patients with rheumatoid arthritis (RA) who have had an inadequate response to disease‐modifying antirheumatic drugs (DMARDs) (referred to as DMARD‐IR) and/or inadequate response to other anti‐TNF agents (referred to as anti‐TNF–IR).MethodsPatients with active RA and a history of DMARD‐IR (≥1 failed regimen) or DMARD‐IR (≥1 failed regimen) and anti‐TNF–IR (1–2 failed regimens) were randomized 1:1 to receive either mavrilimumab 100 mg subcutaneously every other week or golimumab 50 mg subcutaneously every 4 weeks alternating with placebo every 4 weeks, administered concomitantly with methotrexate. The primary end points were the American College of Rheumatology 20% improvement (ACR20), 50% improvement, and 70% improvement response rates at week 24, percentage of patients achieving a Disease Activity Score in 28 joints using C‐reactive protein level (DAS28‐CRP) of <2.6 at week 24, percentage of patients with a score improvement of >0.22 on the Health Assessment Questionnaire (HAQ) disability index (DI) at week 24, and safety/tolerability measures. This study was not powered to formally compare the 2 treatments.ResultsAt week 24, differences in the ACR20, ACR50, and ACR70 response rates between the mavrilimumab treatment group (n = 70) and golimumab treatment group (n = 68) were as follows: in all patients, −3.5% (90% confidence interval [90% CI] −16.8, 9.8), −8.6% (90% CI −22.0, 4.8), and −9.8% (90% CI −21.1, 1.4), respectively; in the anti‐TNF–IR group, 11.1% (90% CI −7.8, 29.9), −8.7% (90% CI −28.1, 10.7), and −0.7% (90% CI −18.0, 16.7), respectively. Differences in the percentage of patients achieving a DAS28‐CRP of <2.6 at week 24 between the mavrilimumab and golimumab groups were −11.6% (90% CI −23.2, 0.0) in all patients, and −4.0% (90% CI −20.9, 12.9) in the anti‐TNF–IR group. The percentage of patients achieving a >0.22 improvement in the HAQ DI score at week 24 was similar between the treatment groups. Treatment‐emergent adverse events were reported in 51.4% of mavrilimumab‐treated patients and 42.6% of golimumab‐treated patients. No deaths were reported, and no specific safety signals were identified.ConclusionThe findings of this study demonstrate the clinical efficacy of both treatments, mavrilimumab at a dosage of 100 mg every other week and golimumab at a dosage of 50 mg every 4 weeks, in patients with RA. Both regimens were well‐tolerated in patients who had shown an inadequate response to DMARDs and/or other anti‐TNF agents.
Myogenic Progenitor Cells Exhibit Type I Interferon–Driven Proangiogenic Properties and Molecular Signature During Juvenile Dermatomyositis
Authors: Gitiaux Cyril , Latroche Claire , Weiss‐Gayet Michèle , Rodero Mathieu P. , Duffy Darragh , Bader‐Meunier Brigitte , Glorion Christophe , Nusbaum Patrick , Bodemer Christine , Mouchiroud Guy , Chelly Jamel , Germain Stéphane , Desguerre Isabelle , Chazaud Bénédicte 
Published: September 2017

ObjectiveJuvenile dermatomyositis (JDM) is an inflammatory pediatric myopathy characterized by focal capillary loss in muscle, followed by progressive recovery upon adequate treatment with immunomodulating drugs, although some patients remain refractory to treatment. While the underlying mechanism of capillary depletion remains uncertain, recent studies have identified an up‐regulation of type I interferon (IFN) expression specific to JDM. Given that myogenic precursor cells (MPCs) exert proangiogenic activity during normal skeletal muscle regeneration, we hypothesized that they may also modulate vascular remodeling/angiogenesis during JDM. The aim of this study was to investigate that hypothesis.MethodsHuman cell cocultures were used to analyze angiogenic properties in patients with JDM, patients with Duchenne's muscular dystrophy (DMD) (control patients for vascular remodeling), and healthy control subjects. Transcriptome analysis was used to examine muscle‐derived MPCs. Histologic analysis of type I IFN in muscle biopsy samples was also performed.ResultsUsing human cell cocultures, we showed highly angiogenic properties of MPCs from JDM patients in association with the expression of an angiogenic molecular signature. Transcriptome analysis of MPCs freshly isolated from muscle samples revealed type I IFN as the master regulator of the most up‐regulated genes in JDM‐derived MPCs. Functionally, treatment of normal MPCs with type I IFN recapitulated the molecular pattern and the proangiogenic functions of JDM‐derived MPCs. In vivo histologic investigation showed that MPCs synthesized type I IFN and major proangiogenic molecules in JDM muscle. Moreover, MPCs derived from JDM muscles that were characterized by strong vasculopathy produced higher levels of type I IFN, confirming MPCs as a cellular source of type I IFN during JDM, and this correlated with the severity of the disease.ConclusionThese results demonstrate a new type I IFN pathway in JDM that activates the production of angiogenic effectors by MPCs, triggering their proangiogenic function to promote vessel recovery and muscle reconstruction.
Deconstructing competency‐based education: An assessment of institutional activity, goals, and challenges in higher education
Authors: Lurie Howard , Garrett Richard 
Published: September 2017

BackgroundThere have been several surveys assessing institutional interest in Competency‐Based Education (CBE), but there is a need for a systematic analysis of how institutions are designing and implementing CBE at the course, program, or institutional level. This initiative proposes to close this research gap and advance the conversation about the scale, impact, and varieties of CBE.MethodsEduventures, an independent higher education research and advisory firm, surveyed institutional leaders and other informed stakeholders on details about the strategies and operations involving CBE at their institutions. The resulting sample includes 251 institutions from across higher education and represents one of the largest samples to date on CBE implementation.ResultsA portrait of CBE emerges as a menu of tools and practices, rather than a monolithic approach or linear path. These findings underscore the need for institutions to carefully weigh the pros and cons of CBE implementation and to proactively select the CBE components that make the most sense for their students and mission.ConclusionWhile interest in CBE is stronger than ever before, it remains a complex innovation. CBE is not simply a delivery mode. It challenges long‐held conventions regarding how curricula are created, instruction is designed and delivered, and skills and knowledge are assessed. The diversity and complexity of CBE requires customized implementation, and near‐term opportunities to accelerate the growth and expand the scale of CBE beyond a set of innovative early adopters may be limited. This complexity emphasizes the merits of a richer array of CBE implementation examples.
Molybdenum Sulfide Nanosheet‐Based Hollow Porous Flat Boxes and Nanotubes for Efficient Electrochemical Hydrogen Evolution
Authors: Chen Liao , Zhu Hongli 
Published: September 2017

AbstractIntriguing amorphous/quasiamorphous molybdenum sulfide (MoSx) materials with active terminal disulfide S22− units have been recognized recently as prominent catalysts for the hydrogen evolution reaction (HER). Here, we diversify the MoSx morphologies and structures by a facile template‐free solvothermal method to prepare fascinating MoSx nanosheet‐based hollow porous flat boxes and nanotubes. As we increase the ethanol concentration in the mixed solvent for the reaction from 60 to 100 vol %, highly dispersed MoSx materials are obtained and the morphologies change from nanosheet to nanosheet‐based hollow porous nanotubes and ultimately to nanosheet‐based hollow porous flat boxes with the increasing S22− content. Catalytic measurements demonstrate that the hollow porous MoSx flat boxes and nanotubes have similar outstanding HER performances and can reach 10 mA cm−2 current at overpotentials of approximately 206 and 210 mV, respectively.
3D Nanoporous Gold with Very Low Parting Limit Derived from Au‐Based Metallic Glass and Enhanced Methanol Electro‐oxidation Catalytic Performance Induced by Metal Migration
Authors: Xu Yi , Yiu Pak Man , Shan Guangcun , Shibayama Tamaki , Watanabe Seiichi , Ohnuma Masato , Huang Wei , Shek Chan‐Hung 
Published: September 2017

AbstractNanoporous gold (NPG) with bi‐continuous ligaments and pores structure has promising potential in functional applications, among which one prominent example is fuel cell electrocatalysts. However, current application of NPG is mostly limited to methanol electro‐oxidation (MOR) due to its weak catalytic performance. Here we report a simple chemical dealloying process for generating peculiar three‐dimensional (3D) free‐standing NPG with ‘parting limit’ as low as 25 % (lower than theoretical ‘paring limit’ 55 %) and high specific surface area (maximum ≈31 m2 g−1) associated with a novel porous ‘cone shaped protrusion’ morphology. This NPG structure possesses the highest specific activity of MOR catalytic performance reported NPG catalysts so far. In addition, taking advantage of this excellent structural feature of the NPG, a nanoporous Pd catalyst (NPG@Pd) thin film was fabricated on the NPG substrate. The NPG@Pd catalyst exhibited greatly enhanced MOR performance (maximum MOR specific activity 2.14 mA cm−2). We attribute the enhancement of MOR activity to the increase of active sites as well as the modification of surface composition and electronic structure due to migration of Au to the Pd thin film layer.
Preparation of Cobalt‐Based Electrodes by Physical Vapor Deposition on Various Nonconductive Substrates for Electrocatalytic Water Oxidation
Authors: Wu Yizhen , Wang Le , Chen Mingxing , Jin Zhaoxia , Zhang Wei , Cao Rui 
Published: September 2017

AbstractArtificial photosynthesis requires efficient anodic electrode materials for water oxidation. Cobalt metal thin films are prepared through facile physical vapor deposition (PVD) on various nonconductive substrates, including regular and quartz glass, mica sheet, polyimide, and polyethylene terephthalate (PET). Subsequent surface electrochemical modification by cyclic voltammetry (CV) renders these films active for electrocatalytic water oxidation, reaching a current density of 10 mA cm−2 at a low overpotential of 330 mV in 1.0 m KOH solution. These electrodes are robust with unchanged activity throughout prolonged chronopotentiometry measurements. This work is thus significant to show that the combination of PVD and CV is very valuable and convenient to fabricate active electrodes on various nonconductive substrates, particularly with flexible polyimide and PET substrates. This efficient, safe and convenient method can potentially be expanded to many other electrochemical applications.
Synergistic Interaction of a Gabapentin‐ Mangiferin Combination in Formalin‐Induced Secondary Mechanical Allodynia and Hyperalgesia in Rats Is Mediated by Activation of NO‐Cyclic GMP‐ATP‐Sensitive K+ Channel Pathway
Authors: Godínez‐Chaparro Beatriz , Quiñonez‐Bastidas Geovanna Nallely , Rojas‐Hernández Isabel Rocío , Austrich‐Olivares Amaya Montserrat , Mata‐Bermudez Alfonso 
Published: September 2017

ABSTRACT

Preclinical Research

Gabapentin is an anticonvulsant used to treat neuropathic pain. Mangiferin is an antioxidant that has antinociceptive and antiallodynic effects in inflammatory and neuropathic pain models. The purpose of this study was to determine the interaction between mangiferin and gabapentin in the development and maintenance of formalin‐induced secondary allodynia and hyperalgesia in rats. Gabapentin, mangiferin, or their fixed‐dose ratio combination were administrated peripherally. Isobolographic analyses was used to define the nature of the interaction of antiallodynic and/or antihyperalgesic effects of the two compounds. Theoretical ED50 values for the combination were 74.31 µg/paw and 95.20 µg/paw for pre‐ and post‐treatment, respectively. These values were higher than the experimental ED50 values, 29.45 µg/paw and 37.73 µg/paw respectively, indicating a synergistic interaction in formalin‐induced secondary allodynia and hyperalgesia. The antiallodynic and antihyperalgesic effect induced by the gabapentin/mangiferin combination was blocked by administration of L‐NAME, the soluble guanylyl cyclase inhibitor, ODQ and glibenclamide. These data suggest that the gabapentin‐ mangiferin combination produces a synergistic interaction at the peripheral level. Moreover, the antiallodynic and hyperalgesic effect induced by the combination is mediated via the activation of an NO‐cyclic GMP‐ATP‐sensitive K+ channel pathway. Drug Dev Res 78 : 390‐402, 2017. © 2017 Wiley Periodicals, Inc.
PTCA (1H‐pyrrole‐2,3,5‐tricarboxylic acid) as a marker for oxidative hair treatment
Authors: Petzel‐Witt Silvana , Meier Sylvia I. , Schubert‐Zsilavecz Manfred , Toennes Stefan W. 
Published: September 2017

AbstractHair analysis for the assessment of alcohol or drug abstinence has become a routine procedure in forensic toxicology. Hair coloration leading to loss of incorporated xenobiotics and to false negative results has turned out to be a major problem. Currently only colored extracts provide hints of manipulations but not bleaching. A liquid chromatographic–tandem mass spectrometric (LC–MS/MS) method was developed and validated to determine 1H‐pyrrole‐2,3,5‐tricarboxylic acid (PTCA), a major oxidation product of melanin. PTCA was determined in natural hair samples (n = 21) after treatment with 3% hydrogen peroxide (H2O2) for 30 or 40 minutes with concentrations up to 12% for 40 minutes. In another series, 12 natural hair samples were submitted to different coloration procedures (henna, tinting, semi‐permanent and permanent dyeing, bleaching) and the changes in PTCA content were determined. A significant increase in the PTCA content was found for both incubation times and increasing H2O2 concentrations. Coloration with henna or tinting had no influence on PTCA levels detected, but a significant increase was observed after semi‐permanent and permanent dyeing and bleaching. As PTCA concentrations in natural hair were found to be in a range of <2.1–16.4 ng/mg (8.4 ± 3.8 ng/mg, mean ± SD, n = 33), a cut‐off of 20 ng/mg is recommended for the distinction between natural vs. excessively oxidized hair. In case of naturally low melanin content (light‐blond or white hair), no marked increase in PTCA may occur. The present study demonstrated that PTCA is formed during oxidative treatment of melanin in hair, which can be used to detect previous hair coloration including oxidation.
Maximum‐likelihood approaches reveal signatures of positive selection in BMP15 and GDF9 genes modulating ovarian function in mammalian female fertility
Authors: Ahmad Hafiz Ishfaq , Liu Guiqiong , Jiang Xunping , Edallew Shishay Girmay , Wassie Teketay , Tesema Birhanu , Yun Yu , Pan Liu , Liu Chenhui , Chong Yuqing , Yu Zhao Jia , Jilong Han 
Published: September 2017

AbstractBone morphogenetic proteins (BMPs) and the growth factors (GDFs) play an important role in ovarian folliculogenesis and essential regulator of processes of numerous granulosa cells. BMP15 gene variations linked to various ovarian phenotypic consequences subject to the species, from infertility to improved prolificacy in sheep, primary ovarian insufficiency in women or associated with minor subfertility in mouse. To study the evolving role of BMP15 and GDF9, a phylogenetic analysis was performed. To find out the candidate gene associated with prolificacy in mammals, the nucleotide sequence of BMP15 and GDF9 genes was recognized under positive selection in various mammalian species. Maximum‐likelihood approaches used on BMP15 and GDF9 genes exhibited a robust divergence and a prompted evolution as compared to other TGFβ family members. Furthermore, among 32 mammalian species, we identified positive selection signals in the hominidae clade resulting to 132D, 147E, 163Y, 191W, and 236P codon sites of BMP15 and 162F, 188K, 206R, 240A, 244L, 246H, 248S, 251D, 253L, 254F and other codon sites of GDF9. The positively selected amino acid sites such as Alanine, Lucien, Arginine, and lysine are important for signaling. In conclusion, this study evidences that GDF9 and BMP15 genes have rapid evolution than other TGFß family members and was subjected to positive selection in the mammalian clade. Selected sites under the positive selection are of remarkable significance for the particular functioning of the protein and consequently for female fertility.