bluuebunny/crossref_metadata_2025_split huggingface dataset:
Using ocean bottom pressure from the gravity recovery and climate experiment (GRACE) to estimate transport variability in the southern Indian Ocean
Authors: Makowski Jessica K. , Chambers Don P. , Bonin Jennifer A. 
Published: May 2015

AbstractPrevious studies have suggested that ocean bottom pressure (OBP) from the Gravity Recovery and Climate Experiment (GRACE) can be used to measure the depth‐averaged, or barotropic, transport variability of the Antarctic Circumpolar Current (ACC). Here, we use GRACE OBP observations to calculate transport variability in a region of the southern Indian Ocean encompassing the major fronts of the ACC. We use a statistical analysis of a simulated GRACE‐like data set to determine the uncertainty of the estimated transport for the 2003.0–2013.0 time period. We find that when the transport is averaged over 60° of longitude, the uncertainty (one standard error) is close to 1 Sv (1 Sv = 106 m3 s−1) for low‐pass filtered transport, which is significantly smaller than the signal and lower than previous studies have found. The interannual variability is correlated with the Southern Annual mode (SAM) (0.61), but more highly correlated with circumpolar zonally averaged winds between 45°S and 65°S (0.88). GRACE transport reflects significant changes in transport between 2007 and 2009 that is observed in the zonal wind variations but not in the SAM index. We also find a statistically significant trend in transport (−1.0 ± 0.4 Sv yr−1, 90% confidence) that is correlated with a local deceleration in zonal winds related to an asymmetry in the SAM on multidecadal periods.
D″ discontinuity structure beneath the North Atlantic from Scd observations
Authors: Yao Yao , Whittaker Stefanie , Thorne Michael S. 
Published: May 2015

AbstractWe analyzed transverse and radial component recordings from the 2010 M6.3 southern Spain earthquake (depth = 620 km) recorded on 370 broadband stations in North America. We grouped these seismograms into subarrays and applied fourth root vespa processing (vespagram analysis) in order to enhance low‐amplitude arrivals. These vespagrams show clear Scd arrivals which indicate the existence of the D″ discontinuity beneath the North Atlantic Ocean (45–60°N, 45–55°W). These observations are best fit with a +2–4% velocity increase at the top of the D″ discontinuity at a height above the core‐mantle boundary of 304 ± 14 km. We do not observe Scd arrivals at the eastern end of our study region which is consistent with the presence of the easternmost edge of the ancient Farallon plate.
Generation of nonlinear electric field bursts in the outer radiation belt through the parametric decay of whistler waves
Authors: Agapitov O. V. , Krasnoselskikh V. , Mozer F. S. , Artemyev A. V. , Volokitin A. S. 
Published: May 2015

AbstractHuge numbers of different nonlinear structures (double layers, electron holes, nonlinear whistlers, etc., referred to as Time Domain Structures, TDS) have been observed by the electric field experiment on the Van Allen Probes. Some of them are associated with whistler waves. Such TDS often emerge on the forward edges of the whistler wave packets and form chains. The parametric decay of a whistler wave into a whistler wave propagating in the opposite direction and an electron acoustic wave is studied experimentally as well as analytically, using Van Allen Probes data. The resulting electron acoustic wave is considered to be the source of electron scale TDS. The measured parameters of the three waves (two whistlers and the electron acoustic wave) are in good agreement with an assumption of their parametric interaction: ω0=ω1+ω2 and . The bicoherence analysis shows the nonlinear nature of the observed electron‐acoustic waves as well as the whistler wave and electron acoustic wave phase relation. The estimated decay instability growth rate shows that the process of three‐wave interaction can develop in a characteristic time smaller than 1 s, thus, the process is rapid enough to explain the observations. This induced parametric interaction can be one of the mechanisms for quasiperiodic TDS generation in the outer Van Allen radiation belt.
Mesoscale eddies and Trichodesmium spp. distributions in the southwestern North Atlantic
Authors: Olson Elise M. , McGillicuddy Dennis J. , Flierl Glenn R. , Davis Cabell S. , Dyhrman Sonya T. , Waterbury John B. 
Published: May 2015

AbstractCorrelations of Trichodesmium colony abundance with the eddy field emerged in two segments of Video Plankton Recorder observations made in the southwestern North Atlantic during fall 2010 and spring 2011. In fall 2010, local maxima in abundance were observed in cyclones. We hypothesized surface Ekman transport convergence as a mechanism for trapping buoyant colonies in cyclones. Idealized models supported the potential of this process to influence the distribution of buoyant colonies over time scales of several months. In spring 2011, the highest vertically integrated colony abundances were observed in anticyclones. These peaks in abundance correlated with anomalously fresh water, suggesting riverine input as a driver of the relationship. These contrasting results in cyclones and anticyclones highlight distinct mechanisms by which mesoscale eddies can influence the abundance and distribution of Trichodesmium populations of the southwestern North Atlantic.
Repetitive speech elicits widespread deactivation in the human cortex: the “Mantra” effect?
Authors: Berkovich‐Ohana Aviva , Wilf Meytal , Kahana Roni , Arieli Amos , Malach Rafael 
Published: May 2015

AbstractBackgroundMantra (prolonged repetitive verbal utterance) is one of the most universal mental practices in human culture. However, the underlying neuronal mechanisms that may explain its powerful emotional and cognitive impact are unknown. In order to try to isolate the effect of silent repetitive speech, which is used in most commonly practiced Mantra meditative practices, on brain activity, we studied the neuronal correlates of simple repetitive speech in nonmeditators – that is, silent repetitive speech devoid of the wider context and spiritual orientations of commonly practiced meditation practices.MethodsWe compared, using blood oxygenated level‐dependent (BOLD) functional magnetic resonance imaging (fMRI), a simple task of covertly repeating a single word to resting state activity, in 23 subjects, none of which practiced meditation before.ResultsWe demonstrate that the repetitive speech was sufficient to induce a widespread reduction in BOLD signal compared to resting baseline. The reduction was centered mainly on the default mode network, associated with intrinsic, self‐related processes. Importantly, contrary to most cognitive tasks, where cortical‐reduced activation in one set of networks is typically complemented by positive BOLD activity of similar magnitude in other cortical networks, the repetitive speech practice resulted in unidirectional negative activity without significant concomitant positive BOLD. A subsequent behavioral study showed a significant reduction in intrinsic thought processes during the repetitive speech condition compared to rest.ConclusionsOur results are compatible with a global gating model that can exert a widespread induction of negative BOLD in the absence of a corresponding positive activation. The triggering of a global inhibition by the minimally demanding repetitive speech may account for the long‐established psychological calming effect associated with commonly practiced Mantra‐related meditative practices.
Sialic Acid Hydroxamate: A Potential Antioxidant and Inhibitor of Metal‐Induced β‐Amyloid Aggregates
Authors: Yadav Rohan , Murthy Raghavendra Vasudeva , Kikkeri Raghavendra 
Published: May 2015

AbstractCurrent methods for Alzheimer's treatment require a three‐component system: metal chelators, antioxidants, and amyloid β (Aβ)‐peptide‐binding scaffolds. We report sialic acid (Sia) hydroxamate as a potential radical scavenger and metal chelator to inhibit Aβ aggregation. A cell viability assay revealed that Sia hydroxamate can protect HeLa and glioblastoma (LN229) cells from oxidative damage induced by the Fenton reaction. Sedimentation and turbidity assays showed profound protection of neuroblastoma SH‐SY5Y cells from metal‐induced Aβ aggregation and neural toxicity.
Bioabbaubarkeit von 2‐Ethylhexylacetat, Methylisobutylketon und Methylethylketon in Biotricklingfiltern
Authors: Gerl Thomas , Engesser Karl‐Heinrich , Dobslaw Daniel 
Published: May 2015

AbstractDie Bioabbaubarkeit eines mit 2‐Ethylhexylacetat, Methylisobutylketon und Methylethylketon kontaminierten Abluftstromes in Biotricklingfiltern wurde hinsichtlich des Einflusses von Nährstoffangebot und Packungsmaterial untersucht. Als Trägermaterialien wurden PU‐Würfel, Hiflow‐Ringe sowie Wurzelholzriss verglichen. Dabei erwiesen sich die PU‐Würfel als das beste Trägermaterial und die Hiflow‐Ringe lieferten den stabilsten Betrieb. Eine quasikontinuierliche Nährstoffzugabe erhöhte und stabilisierte den Wirkungsgrad bei allen drei Reaktoren. Es trat keine gegenseitige Hemmung im Abbau der Komponenten auf.
Synthese von porösen Kohlenstoffmonolithen unter Verwendung von Porenbeton als Templat. Teil II: Untersuchungen mechanischer Eigenschaften
Authors: Taubert Michael , Heider Robert , Erlitz Marcel , Hille Eva , Lange Andreas , Enke Dirk , Klepel Olaf 
Published: May 2015

AbstractFür den Einsatz poröser Kohlenstoffmaterialien in durchströmten Apparaturen eignen sich besonders monolithische Formen. Ein möglicher Syntheseweg für diese Materialien ist die Templatsynthese. Poröse Kohlenstoffmonolithe wurden unter Verwendung von Porenbeton als Templat präpariert. Erste systematische Untersuchungen zur mechanischen Stabilität zeigen das Potenzial solcher Materialien für einen Einsatz in technischen Komponenten. Es konnte nachgewiesen werden, dass diese Kohlenstoffformkörper stabil sowohl hinsichtlich mechanischer Druckbeanspruchung als auch Durchströmung mit Wasser sind.
Syntheses of (R)‐ and (S)‐3‐Methylheptanoic Acids
Authors: Zhang Shunji , Shi Yong , Tian Weisheng 
Published: May 2015

AbstractStarting from chiral methyl molecules 3 and 4, both derived from (R)‐4‐methyl‐δ‐valerolactone, we have accomplished the synthesis of (R) and (S)‐3‐methylheptanoic acids. Our methods are amendable to the syntheses of a wide variety of chiral 3‐methyl alkanoic acids.
A Robust Solution‐Based Approach to Monodisperse Hybrid Janus Nanofibers
Authors: Chen Chunyang , Yi Junqi , Dong Haiyan , Chen Daoyong 
Published: May 2015

AbstractMonodisperse hybrid Janus nanofibers with the structure that one Au nanoparticle (AuNP) is connected to one end of a polymeric nanofiber were prepared by the self‐assembly between polymeric micelles and the tadpole‐like conjugates resulting from one‐to‐one complexation of long DNA chains with AuNPs.
Dithienopyrrole Based Small Molecule with Low Band Gap for Organic Solar Cells
Authors: Li Miaomiao , Ni Wang , Feng Huanran , Kan Bin , Wan Xiangjian , Zhang Yamin , Yang Xuan , Chen Yongsheng 
Published: May 2015

AbstractA low band gap acceptor‐donor‐acceptor (A‐D‐A) small molecule donor material, named DR3TDTN, has been designed and synthesized for solution‐processed organic solar cells. DR3TDTN shows narrow optical band gap with value of 1.49 eV and broad absorption spectrum from 300 to 820 nm. The HOMO and LUMO energy levels of DR3TDTN are −4.74 and −3.26 eV, respectively. The optimized photovoltaic device based on DR3TDTN:PCB71BBM blend film shows a power conversion efficiency of 3.03% with an open‐circuit voltage of 0.67 V, a short‐circuit current of 8.22 mA·cmP−2 and fill factor of 0.55.
Changing to Poly(rod‐coil) Polymers: a Promising Way for an Optoelectronic Compound to Improve Its Film Formation
Authors: Shao Wei , Liang Long , Xiang Xuan , Li Hong‐jiao , Zhao Fu‐gang , Li Wei‐shi 
Published: May 2015

AbstractGood film formation is one of basic requirements for organic optoelectronic materials to achieve the capability for fabrication of large area devices. Small molecular optoelectronic compounds have a definite chemical structure and clear device performance, and thus are welcomed in the field. However, they are generally suffering from poor film formation, especially in a large area. For addressing it, this contribution proposes and demonstrates a strategy, that is, changing them into poly(rod‐coil) polymers. With one optoelectronic compound [BDT(DTBT)2] and three poly(rod‐coil) polymers (P1, P2, and P3) having different non‐conjugated coil segments as examples, the work clearly shows that the change to poly(rod‐coil) polymers keeps many basic optoelectronic properties of the reference compound, including light absorption in solution, bandgap and frontier orbital energy levels, but suppresses strong intermolecular interactions and crystalline structure in film state. Further comparisons on film formation quality on glass and ITO glass illustrate that all the three polymers have a better film formation property than the reference compound.
A Triptycene‐Based Porous Organic Polymer that Exhibited High Hydrogen and Carbon Dioxide Storage Capacities and Excellent CO2/N2 Selectivity
Authors: Lu Xi‐Long , Zhou Tian‐You , Wu Doufeng , Wen Qiang , Zhao Xin , Li Qiaowei , Xiang Qun , Xu Jia‐Qiang , Li Zhan‐Ting 
Published: May 2015

AbstractA novel porous organic polymer (POP) has been constructed through the condensation of triptycene tricatechol and 1,3,5‐benzenetris(4‐phenylboronic acid). This triptycene‐based POP exhibited high H2 uptake (up to 1.84 wt% at 77 K, 1 bar), large CO2 adsorption capacity (up to 18.1 wt% at 273K, 1 bar), and excellent CO2/N2 adsorption selectivity (up to 120/1). The influence of solvent on the gas adsorption performance of the POP has also been investigated.
TBHP/TEMPO‐Mediated Oxidative Synthesis of Imides from Amides
Authors: Yu Hui , Chen Yuegang , Zhang Yonghao 
Published: May 2015

AbstractA new protocol for the synthesis of imides has been developed. In the presence of copper catalyst, N‐benzylamides were oxidized to the corresponding imides by TBHP/TEMPO system in moderate to good yields.
An Environmentally Benign Catalytic Method for Versatile Synthesis of 1,4‐Dihydropyridines via Multicomponent Reactions
Authors: Cao Shuo , Zhong Shanshan , Hu Changfeng , Wan Jie‐Ping , Wen Chengping 
Published: May 2015

AbstractThe synthesis of diverse 1,4‐dihydropyridines have been achieved via the multicomponent reactions of aldehydes, enaminones and amines. The reactions have been smoothly performed in water to provide all products with moderate to excellent yields by using lactic acid as a green catalyst.
Self‐assembly of Micrometer‐long DNA Nanoribbons with Four Oligonucleotides
Authors: Chao Jie , Ouyang Xiangyuan , Peng Hongzhen , Su Shao , Wang Lianhui 
Published: May 2015

AbstractDNA nanostructures have found widespread applications in areas including nanoelectronics and biomedicine. However, traditional DNA origami needs a long single‐stranded virus DNA and hundreds of short DNA strands, which make this method complicated and money‐consuming. Here, we present a protocol for the assembly of DNA nanoribbons with only four oligonucleotides. DNA nanoribbons with different dimensions were successfully assembled with a 96‐base scafford strand and three short staples. These biotinylated nanoribbons could also be decorated with streptavidins. This approach suggests that there exist great design spaces for the creation of simple nucleic acid nanostructures which could facilitate their application in plasmonic or drug delivery.
Determinants of conifer distributions across peatland to forest gradients in the coastal temperate rainforest of southeast Alaska
Authors: Bisbing Sarah M. , Cooper David J. , D'Amore David V. , Marshall Kristin N. 
Published: May 2015

AbstractWetland determination relies on assumptions that site hydrologic and edaphic conditions limit plant species to certain environments. For example, using species' wetland indicator status for wetland determination assumes that tolerance of wetland conditions best explains distributional patterns. However, abiotic and biotic factors often interact to create complex plant responses across different environments. To evaluate these interactions, we used a hydrologic gradient in the coastal temperate rainforest of southeast Alaska to (1) quantify the primary determinants of conifer distributions, (2) identify thresholds in environmental factors limiting species' success and (3) assess current wetland indicator status of local conifers (Pinus contorta,Picea sitchensis, andTsuga heterophylla). Data were collected using a hierarchical sampling scheme and analyzed within a Bayesian framework. Topography and hydrologic regime were the primary determinants of distributional patterns, but species were limited by specific microsite factors. Competitively dominantP. sitchensisoccurred where hydrology, pH, and nitrogen were most favorable for establishment, while stress‐tolerantP. contortawas competitively excluded from these sites.Tsugaheterophyllaoccurred across the gradient but took advantage of drier conditions, which promoted biomass accumulation. Tree distributions were limited by the interaction between abiotic and biotic factors rather than by abiotic tolerance alone. This knowledge of local and regional drivers of species' distributions and the relative importance of interacting abiotic and biotic drivers provide critical information for land management and regulation. Wetland delineation procedures can be improved through application of the regional empirical limits identified for plant species, as implemented and addressed in this study. Copyright © 2015 John Wiley & Sons, Ltd.
Facile Synthesis of (110)‐Plane‐Exposed Au Microflowers as High Sensitive Hydrogen Peroxide Sensors
Authors: Yu Fengjiao , Liu Zhong , Zhou Wuzong 
Published: May 2015

AbstractA flower‐like Au microstructure with a dominantly exposed active (110) plane has been prepared by a simple, facile method at room temperature. Various experimental factors that can control the shape of the Au microflowers have been investigated and optimized. Furthermore, the glassy carbon electrode modified with these Au microflowers exhibits high electrochemical activity towards H2O2 reduction. The sensor shows a linear range from 10 μM to 5.53 mM with a detection limit of 2 μM, which can be attributed to the exposed (110) planes and 3D hierarchical structure of the Au microflowers.
Apparent Electrophilic Fluorination of 1,3‐Dicarbonyl Compounds Using Nucleophilic Fluoride Mediated by PhI(OAc)2
Authors: Nash Toby J. , Pattison Graham 
Published: May 2015

AbstractThe apparent electrophilic fluorination of 1,3‐dicarbonyl compounds using Et3N·3HF as a nucleophilic fluoride source is reported. This reaction requires PhI(OAc)2 as oxidant and can be conducted safely in standard laboratory glassware. Alternative selectivity compared to Selectfluor was observed in some cases. This approach may reduce our reliance on difficult‐to‐handle fluorine gas and expensive electrophilic fluorinating agents derived from elemental fluorine. Mechanistic analysis related to the active fluorinating species and fluoride/acetate exchange is presented.
Thin film growth of Cd1‐xZnxTe and its application to X‐ray sensor
Authors: Mochizuki K. , Takahashi J. , Nakamura N. 
Published: May 2015

AbstractCd1‐xZnxTe (x∼0.5) thin films with less than 300μm are grown on ITO/glass substrate by Hot‐wall and PVT methods, one of the sublimation methods. In order to obtain the films with high resistivity and good quality for X‐ray sensor, three attempts have been tried in the experiments. The one is stoichiometry control of CZT (x = 0.04) films, which were grown under controlled Cd vapor pressure. The second is excess chlorine doping to the films (x = 0.04) by controlling CdCl2 vapor pressure during growth process. The third is to change composition x = 0.04‐0.50, which increases band gap. Through these methods, best films with good X‐ray response was obtained for the third case of the films with the composition x = 0.20. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spectroscopic ellipsometry studies of as‐prepared and annealed CdS:O thin films
Authors: Khalilova Khuraman , Shim YongGu , Hasanov Ilham , Asaba Ryo , Wakita Kazuki , Mamedov Nazim 
Published: May 2015

AbstractCadmium sulfide thin films on soda lime substrates were obtained by rf‐magnetron sputtering in argon‐oxygen atmosphere. As‐prepared and vacuum annealed films were then studied by spectroscopic ellipsometry at room temperature over photon energy range from 0.5 to 6 eV. The obtained ellipsometric data were treated using optical dispersion models based on Gaussian type oscillators. Dielectric function of oxygen‐free films, as well as those obtained under 3% of O/Ar partial pressure was reliably restored. At the same time, dielectric function obtained for 5% CdS:O can be regarded only as an average over several materials since our XPS examination disclosed presence of several compounds in thin films deposited at O/Ar ratios higher than 3%. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of preheating time on uniformity of electrodeposited Cu2ZnSnS4 thin films studied by carrier lifetime and photoluminescence measurements
Authors: Hamada T. , Fukuyama A. , Jiang F. , Ikeda S. , Ikari T. 
Published: May 2015

AbstractCu2ZnSnS4 (CZTS) is paid attention to the low‐cost and nontoxic solar cell material. In this study, CZTS thin film was deposited by using an electrodeposition technique followed by a sulfurization after preheating the deposited metallic precursor layer. We investigated the film properties of CZTS thin films for understanding the effect of preheating time on the photovoltaic properties such as carrier lifetime and recombination mechanism by using a microwave photoconductivity decay (μ‐PCD) and a photoluminescence (PL) measurement. The results of the μ‐PCD measurements showed that carrier lifetime increased with increasing the preheating time and longer carrier lifetime was observed in a part of deposited thin film. The PL measurements showed the peak energy shift to lower energy region by a surface position of the sample preheated for 150 min. We found the CZTS crystal quality improved but the homogeneity worsened with increasing the preheating time. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preparation and characterization of Cu2Six Sn1‐xS3
Authors: Toyonaga Kotoba , Araki Hideaki 
Published: May 2015

AbstractCu2SnS3 is a promising compound for use as an absorber layer in thin film solar cells because it is made up of low‐cost and abundant elements, and has a high optical absorption coefficient. However, the band gap energy of monoclinic Cu2SnS3 is less than the value required for absorber layers in single‐junction solar cells. On the other hand, the band gap energy of Cu2SiS3 was reported to be approximately 2.5 eV, which is sufficiently large for this purpose. Therefore, in the present study, an attempt was made to synthesize Cu2Six Sn1‐xS3, which is a solid solution between Cu2SnS3 and Cu2SiS3. In X‐ray diffraction patterns from the synthesized compounds, the diffraction peaks were found to shift to higher 2θ values with increasing x, indicating a decrease in the lattice constants. In addition, the estimated band gap energy increased from 0.85 to 2.56 eV with increasing x. Cu2Six Sn1‐xS3 is therefore a potential candidate for use as the absorber layer in thin film solar cells because its band gap energy can be adjusted simply by varying its composition. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)