bluuebunny/crossref_metadata_2025_split huggingface dataset:
Protective effect ofRhus coriariafruit extracts against hydrogen peroxide-induced oxidative stress in muscle progenitors and zebrafish embryos
Authors: Najjar Fadia , Rizk Francine , Carnac Gilles , Nassar Rim , Jabak Sara , Sobolev Anatoly Petrovich , Bou Saada Yara , El Sabban Marwan , Hamade Aline 
Published: December 2017

Background and PurposeOxidative stress is involved in normal and pathological functioning of skeletal muscle. Protection of myoblasts from oxidative stress may improve muscle contraction and delay aging. Here we studied the effect ofR. coriariasumac fruit extract on human myoblasts and zebrafish embryos in conditions of hydrogen peroxide-induced oxidative stress.Study Design and MethodsCrude ethanolic 70% extract (CE) and its fractions was obtained from sumac fruits. The composition of sumac ethyl acetate EtOAc fraction was studied by1H NMR. The viability of human myoblasts treated with CE and the EtOAc fraction was determined by trypan blue exclusion test. Oxidative stress, cell cycle and adhesion were analyzed by flow cytometry and microscopy. Gene expression was analyzed by qPCR.ResultsThe EtOAc fraction (IC502.57 µg/mL) had the highest antioxidant activity and exhibited the best protective effect against hydrogen peroxide-induced oxidative stress. It also restored cell adhesion. This effect was mediated by superoxide dismutase 2 and catalase. Pre-treatment of zebrafish embryos with low concentrations of the EtOAc fraction protected them from hydrogen peroxide-induced deathin vivo.1H NMR analysis revealed the presence of gallic acid in this fraction.ConclusionRhus coriariaextracts inhibited or slowed down the progress of skeletal muscle atrophy by decreasing oxidative stress via superoxide dismutase 2 and catalase-dependent mechanisms.
MMS Observation of Shock‐Reflected He++ at Earth's Quasi‐Perpendicular Bow Shock
Authors: Broll Jeffrey Michael , Fuselier S. A. , Trattner K. J. , Schwartz S. J. , Burch J. L. , Giles B. L. , Anderson B. J. 
Published: December 2017

AbstractSpecular reflection of protons at Earth's supercritical quasi‐perpendicular bow shock has long been known to lead to the thermalization of solar wind particles by velocity‐space dispersion. The same process has been proposed for He++ but could not be confirmed previously due to insufficient time resolution for velocity distribution measurements. We present observations and simulations of a bow shock crossing by the Magnetospheric Multiscale (MMS) mission on 20 November 2015 indicating that a very similar reflection process for He++ is possible, and further that the part of the incoming distribution with the highest probability of reflecting is the same for H+ and He++. However, the reflection process for He++ is accomplished by deeper penetration into the downstream magnetic fields.
Variation in Rising Limb of Colorado River Snowmelt Runoff Hydrograph Controlled by Dust Radiative Forcing in Snow
Authors: Painter Thomas H. , Skiles S. McKenzie , Deems Jeffrey S. , Brandt W. Tyler , Dozier Jeff 
Published: December 2017

AbstractCommon practice and conventional wisdom hold that fluctuations in air temperature control interannual variability in snowmelt and subsequent river runoff. However, recent observations in the Upper Colorado River Basin confirm that net solar radiation and by extension radiative forcing by dust deposited on snow cover exerts the primary forcing on snowmelt. We show that the variation in the shape of the rising limb of the annual hydrograph is controlled by variability in dust radiative forcing and surprisingly is independent of variations in winter and spring air temperatures. These observations suggest that hydroclimatic modeling must be improved to account for aerosol forcings of the water cycle. Anthropogenic climate change will likely reduce total snow accumulations and cause snowmelt runoff to occur earlier. However, dust radiative forcing of snowmelt is likely consuming important adaptive capacity that would allow human and natural systems to be more resilient to changing hydroclimatic conditions.
Predicting Electron Population Characteristics in 2‐D Using Multispectral Ground‐Based Imaging
Authors: Grubbs Guy , Michell Robert , Samara Marilia , Hampton Donald , Jahn Jorg‐Micha 
Published: December 2017

AbstractGround‐based imaging and in situ sounding rocket data are compared to electron transport modeling for an active inverted‐V type auroral event. The Ground‐to‐Rocket Electrodynamics‐Electrons Correlative Experiment (GREECE) mission successfully launched from Poker Flat, Alaska, on 3 March 2014 at 11:09:50 UT and reached an apogee of approximately 335 km over the aurora. Multiple ground‐based electron‐multiplying charge‐coupled device (EMCCD) imagers were positioned at Venetie, Alaska, and aimed toward magnetic zenith. The imagers observed the intensity of different auroral emission lines (427.8, 557.7, and 844.6 nm) at the magnetic foot point of the rocket payload. Emission line intensity data are correlated with electron characteristics measured by the GREECE onboard electron spectrometer. A modified version of the GLobal airglOW (GLOW) model is used to estimate precipitating electron characteristics based on optical emissions. GLOW predicted the electron population characteristics with 20% error given the observed spectral intensities within 10° of magnetic zenith. Predictions are within 30% of the actual values within 20° of magnetic zenith for inverted‐V‐type aurora. Therefore, it is argued that this technique can be used, at least in certain types of aurora, such as the inverted‐V type presented here, to derive 2‐D maps of electron characteristics. These can then be used to further derive 2‐D maps of ionospheric parameters as a function of time, based solely on multispectral optical imaging data.
Meteorological and Land Surface Properties Impacting Sea Breeze Extent and Aerosol Distribution in a Dry Environment
Authors: Igel Adele L. , van den Heever Susan C. , Johnson Jill S. 
Published: December 2017

AbstractThe properties of sea breeze circulations are influenced by a variety of meteorological and geophysical factors that interact with one another. These circulations can redistribute aerosol particles and pollution and therefore can play an important role in local air quality, as well as impact remote sensing. In this study, we select 11 factors that have the potential to impact either the sea breeze circulation properties and/or the spatial distribution of aerosols. Simulations are run to identify which of the 11 factors have the largest influence on the sea breeze properties and aerosol concentrations and to subsequently understand the mean response of these variables to the selected factors. All simulations are designed to be representative of conditions in coastal sub tropical environments and are thus relatively dry, as such they do not support deep convection associated with the sea breeze front. For this dry sea breeze regime, we find that the background wind speed was the most influential factor for the sea breeze propagation, with the soil saturation fraction also being important. For the spatial aerosol distribution, the most important factors were the soil moisture, sea‐air temperature difference, and the initial boundary layer height. The importance of these factors seems to be strongly tied to the development of the surface‐based mixed layer both ahead of and behind the sea breeze front. This study highlights potential avenues for further research regarding sea breeze dynamics and the impact of sea breeze circulations on pollution dispersion and remote sensing algorithms.
NMR mit Tischgeräten und deren Anwendungen von der Materialwissenschaft bis zur organischen Chemie
Authors: Blümich Bernhard , Singh Kawarpal 
Published: December 2017

AbstractDie NMR‐Spektroskopie ist eine unverzichtbare Analysemethode. Bis vor kurzem erforderten die Geräte viel Platz, waren teuer und schwer zu bedienen. Dies hat sich mit der Einführung kompakter NMR‐Spektrometer geändert, die sich für die Analyse kleiner Moleküle auf der Laborbank eignen. Solche Spektrometer sind mit Permanentmagneten für1H‐NMR‐Frequenzen zwischen 40 und 80 MHz ausgestattet. Erst seit wenigen Jahren gibt es kleine Permanentmagnete mit homogenen Magnetfeldern für hochaufgelöste Spektroskopie. Tischgeräte mit inhomogenen Feldern werden schon seit 40 Jahren zur Charakterisierung von Lebensmitteln und Materialien über Relaxations‐ und Diffusionsmessungen genutzt. Ähnliche NMR‐Geräte messen diese Parameter im Streufeld außerhalb des Magneten. Sie werden zur Untersuchung von Bohrlochwänden in Ölquellen sowie für zerstörungsfreie Analysenverwendet. Der gegenwärtige Stand von NMR‐Spektroskopie, ‐Bildgebung und ‐Relaxometrie wird hier anhand repräsentativer Beispiele beschrieben.
Visualization of Heterogeneous Oxygen Storage Behavior in Platinum‐Supported Cerium‐Zirconium Oxide Three‐Way Catalyst Particles by Hard X‐ray Spectro‐Ptychography
Authors: Hirose Makoto , Ishiguro Nozomu , Shimomura Kei , Burdet Nicolas , Matsui Hirosuke , Tada Mizuki , Takahashi Yukio 
Published: December 2017

AbstractThe cerium density and valence in micrometer‐size platinum‐supported cerium–zirconium oxide Pt/Ce2Zr2Ox (x=7–8) three‐way catalyst particles were successfully mapped by hard X‐ray spectro‐ptychography (ptychographic‐X‐ray absorption fine structure, XAFS). The analysis of correlation between the Ce density and valence in ptychographic‐XAFS images suggested the existence of several oxidation behaviors in the oxygen storage process in the Ce2Zr2Ox particles. Ptychographic‐XAFS will open up the nanoscale chemical imaging and structural analysis of heterogeneous catalysts.
CO2 to Terpenes: Autotrophic and Electroautotrophic α‐Humulene Production with Cupriavidus necator
Authors: Krieg Thomas , Sydow Anne , Faust Sonja , Huth Ina , Holtmann Dirk 
Published: December 2017

AbstractWe show that CO2 can be converted by an engineered “Knallgas” bacterium (Cupriavidus necator) into the terpene α‐humulene. Heterologous expression of the mevalonate pathway and α‐humulene synthase resulted in the production of approximately 10 mg α‐humulene per gram cell dry mass (CDW) under heterotrophic conditions. This first example of chemolithoautotrophic production of a terpene from carbon dioxide, hydrogen, and oxygen is a promising starting point for the production of different high‐value terpene compounds from abundant and simple raw materials. Furthermore, the production system was used to produce 17 mg α‐humulene per gram CDW from CO2 and electrical energy in microbial electrosynthesis (MES) mode. Given that the system can convert CO2 by using electrical energy from solar energy, it opens a new route to artificial photosynthetic systems.
Chiral Bifunctional Phosphine‐Carboxylate Ligands for Palladium(0)‐Catalyzed Enantioselective C−H Arylation
Authors: Yang Lei , Neuburger Markus , Baudoin Olivier 
Published: December 2017

AbstractPrevious enantioselective Pd0‐catalyzed C−H activation reactions proceeding via the concerted metalation‐deprotonation mechanism employed either a chiral ancillary ligand, a chiral base, or a bimolecular mixture thereof. This study describes the development of new chiral bifunctional ligands based on a binaphthyl scaffold which incorporates both a phosphine and a carboxylic acid moiety. The optimal ligand provided high yields and enantioselectivities for a desymmetrizing C(sp2)−H arylation leading to 5,6‐dihydrophenanthridines, whereas the corresponding monofunctional ligands showed low enantioselectivities. The bifunctional system proved applicable to a range of substituted dihydrophenanthridines, and allowed the parallel kinetic resolution of racemic substrates.
Die katalytische, asymmetrische Mukaiyama‐Michael‐Reaktion von Silylketenacetalen mit α,β‐ungesättigten Methylestern
Authors: Gatzenmeier Tim , Kaib Philip S. J. , Lingnau Julia B. , Goddard Richard , List Benjamin 
Published: December 2017

Abstractα,β‐Ungesättigte Ester sind einfach zugängliche, aber schwierig zu aktivierende Substrate in der asymmetrischen Katalyse. Wir stellen hier eine effiziente, allgemeine und hochenantioselektive Mukaiyama‐Michael‐Reaktion von Silylketenacetalen mit α,β‐ungesättigten Methylestern vor, die durch silylierte Imidodiphosphorimidat(IDPi)‐Lewis‐Säuren katalysiert wird.
Water‐soluble binder PAALi with terpene resin emulsion as tackifier for LiFePO4 cathode
Authors: He Jiarong , Zhong Haoxiang , Zhang Lingzhi 
Published: December 2017

ABSTRACTTerpene resin (TS) emulsion has been adopted as a tackifier in lithium polyacrylate (PAALi) as water‐soluble binder for LiFePO4 (LFP) cathode in Li‐ion batteries. TS–PAALi composite binder with optimal ratio of 1:1 (denoted as TS1–PAALi1), shows improved flexibility and enhanced adhesion capability of 0.170 N/cm in comparison with 0.120 N/cm of PAALi after introducing TS as adhesion enhancing agent, which is comparable with that of nonaqueous poly(vinylidene difluoride) (PVDF, 0.171 N/cm) and much better than aqueous sodium carboxymethyl cellulose (CMC, 0.045 N/cm). The electrochemical characteristics of LFP with TS1–PAALi1 have been investigated and further compared with those of PAALi, CMC, and PVDF. LFP with TS1–PAALi1 exhibits superior cycling stability and rate capability, maintaining 65.57% capacity of 0.2 C at 5 C rate in comparison with 60.73%, 57.83%, and 34.79% for PAALi, CMC, and PVDF, respectively. In addition, LFP with TS1–PAALi1 displays excellent cycling performance almost without any capacity fading at 60 °C after 45 cycles at 1 C, much better than that of PAALi, CMC, and PVDF. Cyclic voltammetry and electrochemical impedance spectroscopy reveal that LFP with TS1–PAALi1 has a smaller redox potential difference, lower electrode polarization, and a more favorable electrochemical kinetics (fast lithium diffusion rate) than that of PAALi, CMC, and PVDF, thus more superior electrochemical performances. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46132.
Noncoded amino acids in protein engineering: Structure–activity relationship studies of hirudin–thrombin interaction
Authors: De Filippis Vincenzo , Acquasaliente Laura , Pontarollo Giulia , Peterle Daniele 
Published: December 2017

AbstractThe advent of recombinant DNA technology allowed to site‐specifically insert, delete, or mutate almost any amino acid in a given protein, significantly improving our knowledge of protein structure, stability, and function. Nevertheless, a quantitative description of the physical and chemical basis that makes a polypeptide chain to efficiently fold into a stable and functionally active conformation is still elusive. This mainly originates from the fact that nature combined, in a yet unknown manner, different properties (i.e., hydrophobicity, conformational propensity, polarizability, and hydrogen bonding capability) into the 20 standard natural amino acids, thus making difficult, if not impossible, to univocally relate the change in protein stability or function to the alteration of physicochemical properties caused by amino acid exchange(s). In this view, incorporation of noncoded amino acids with tailored side chains, allowing to finely tune the structure at a protein site, would facilitate to dissect the effects of a given mutation in terms of one or a few physicochemical properties, thus much expanding the scope of physical organic chemistry in the study of proteins. In this review, relevant applications from our laboratory will be presented on the use of noncoded amino acids in structure–activity relationships studies of hirudin binding to thrombin.
Die hohen Berge in der Tiefe
Authors: George Kai Horst 
Published: December 2017

ZusammenfassungViele Vertreter der sogenannten Meiofauna zeigen trotz ihrer geringen Körpergröße (≤ 1 mm), einer fast ausschließlich substratgebundenen Lebensweise, fehlenden Freiwasserstadien und nur wenigen Nachkommen eine sehr weite bis weltweite Verbreitung in den Ozeanen. Dieses als „Meiofauna‐Paradoxon“ bekannte Phänomen fällt besonders bei Arten des Flachwassers ins Auge, für die die riesigen Tiefseegebiete der Meere eine schier unüberwindliche Barriere darstellen. Bei dem Versuch, das „Meiofauna‐Paradoxon“ zu verstehen, haben Forscher in den vergangenen Jahrzehnten zunehmend Seeberge ins Visier genommen. Diese Erhebungen verteilen sich in großer Zahl über die Ozeane. Sie ragen aus der Tiefsee empor und erreichen häufig lichtdurchflutete Regionen. Somit könnten Seeberge (ebenso wie ozeanische Inseln) zur Ausbreitung mariner Meiofauna beitragen, indem sie eine Funktion als „Trittsteine“ bei der Überwindung großer Entfernungen einnehmen. Untersuchungen der letzten Jahre deuten darauf hin, dass Seeberge zumindest für einzelne Tiergruppen der Meiofauna durchaus als Trittsteine fungieren.
Programmierter Zelltod bei Bakterien
Authors: Hell Regina , Schumann Wolfgang 
Published: December 2017

ZusammenfassungDie biologische Grundlage des programmierten Zelltodes (programmed cell death, PCD) der Bakterien sind zwei Moleküle, ein stabiles Protein‐Toxin und ein instabiles Antitoxin welches permanent synthetisiert werden muss. Beide Komponenten zusammen werden als TA‐Modul bezeichnet. Wird die Synthese des Antitoxins blockiert oder wird es abgebaut, dann übt das nun freie Toxin entweder eine bakteriostatische oder eine bakterizide Wirkung aus. PCD kann sich auch auf andere Zellen auswirken und dort zu Kannibalismus und Geschwistermord führen. Zum Schluss werden zwei Beispiele der Anwendung von TA‐Modulen in der Biotechnologie beschrieben.
Nachrichten des Verbandes Biologie, Biowissenschaften & Biomedizin in Deutschland
Authors: Lipphardt Veronika , Staubach Fabian 
Published: December 2017

Ausbildung & KarriereJetzt bewerben: Ars legendi‐Fakultätenpreis Mathematik und Naturwissenschaften 2018Bündnis TA legt Forderungskatalog vorWissenschaft & GesellschaftNeue Kooperation mit der Initiative „Tierversuche verstehen“Digitale SequenzdatenNach der BundestagswahlLandesverbändeNordrhein‐Westfalen
Environmental Policy, Sustainable Development, Governance Mechanisms and Environmental Performance
Authors: Haque Faizul , Ntim Collins G 
Published: December 2017

AbstractWe investigate the effects of environmental policy (Climate Change Act – CCA), sustainable development frameworks (Global Reporting Initiative – GRI; UN Global Compact – UNGC) and corporate governance (CG) mechanisms on environmental performance (carbon reduction initiatives – CRIs; actual carbon performance – GHG emissions) of UK listed firms. We use the generalized method of moments (GMM) estimation technique to analyse data consisting of 2245 UK firm‐year observations over the 2002–2014 period. First, we find that the CCA has a positive effect on CRIs, and this effect is stronger in better‐governed firms. Second, we find that the GRI‐based framework is positively associated with CRIs. Third, we find that firms with poor CG structures have lower actual carbon performance compared with their better‐governed counterparts. Overall, our evidence suggests that firms can symbolically conform to environmental policy (CCA) and sustainable development frameworks (GRI, UNGC) by engaging in CRIs without necessarily improving actual environmental performance (GHG emissions) substantively. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment
Resource Recovery from Low‐Grade Ore Deposits and Mining Residuals by Biohydrometallurgy and Membrane Technology. Potentials and Case Studies
Authors: Werner Arite , Meschke Katja , Bohlke Kevin , Daus Birgit , Haseneder Roland , Repke Jens‐Uwe 
Published: December 2017

AbstractThe recovery of strategic elements from secondary mineral sources and low‐grade ores is of increasing relevance due to a changing global market as well as for reasons of sustainability. The present article shows the potential of biohydrometallurgy as an effective technology for mobilization of metals from secondary sources. Furthermore, the application of membrane separation as a successful technique to recover metals from bioleaching solutions is presented. These issues are discussed within the scope of recent research projects.
Preparation of Keggin‐Type Polyoxometallate/Polypyrrole Composite Microtubes and Their Assist‐Catalytic Properties Towards Methanol Oxidation
Authors: Yuan Yue , Li Guangzhe , Ding Yanhong , Shilf Khan , Zhou Wanli , Peng Jun 
Published: December 2017

AbstractPolypyrrole@M‐SiW12 (M=Fe3+, Cu2+) composite microtubes were obtained through the in situ chemically oxidative polymerization of pyrrole (Py) to polypyrrole (Ppy) in M‐SiW12 microtubes with oxidants Fe3+ andCu2+ doped into polyoxometallate (POM) microtubes. The biggest oxidation peak current obtained from the Pt/C/PPy@Cu‐SiW12/glassy carbon electrode was 3.5 mA. PPy@M‐SiW12 microtubes provide a new catalyst supporter for the Pt/C catalyst, and present good electrocatalytic activity toward methanol oxidation, perhaps owing to a synergy effect coming from PPy and POM.
Sandwich‐Like Nanosheets of a N‐Doped Porous Carbon/Graphene Composite with Enhanced Electrochemical Properties for Lithium and Sodium Storage
Authors: Qin Weiwei , Teng Yongqiang , Zhang Junke , Xiao Xinfeng , Li Yuan , Li Zhenyu 
Published: December 2017

AbstractEnergy storage systems, including lithium‐/sodium‐ion batteries (LIBs/SIBs), are important for being able to use renewable energies efficiently. The anode material is a vital link in the great industrialization chain. Herein, a sandwich‐like N‐doped porous carbon/graphene (N‐HCG) composite has been successfully achieved by using a facile and low‐temperature liquid‐phase method with melamine as the nitrogen source, followed by a carbonization process. The composite possesses a high specific surface area of 282.4 m2 g−1. As an anode in lithium‐ion batteries, N‐HCG delivers a capacity of 643 mAh g−1 at 100 mA g−1, and a high capacity of 406 mAh g−1 is maintained even at 5 A g−1 after 2700 cycles. For sodium‐ion batteries, the obtained capacities of the N‐HCG electrodes are 208 mAh g−1 (100 mA g−1 for 120 cycles) and 145 mAh g−1 (1000 mA g−1 for 700 cycles). The excellent electrochemical performance including the rate capability and lifespan of N‐HCG can be attributed to the synergistic effects of the 2D sandwich‐like nanosheets with pores and extrinsic nitrogen doping. Thus, the as‐prepared N‐HCG composite is a highly promising anode material for LIB/SIB applications.