bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bioclimatic analyses for the distributions ofOnthophagus nuchicornis,Onthophagus taurus, andDigitonthophagus gazella(Coleoptera: Scarabaeidae) in North America
Authors: Floate K.D. , Watson D.W. , Weiss R.M. , Olfert O. 
Published: June 2017

AbstractOnthophagus nuchicornis(Linnaeus),Onthophagus taurus(Schreber), andDigitonthophagus gazella(Fabricius) (Coleoptera: Scarabaeidae: Scarabaeinae: Onthophagini) are species of dung beetles that have been used in relocation programmes to accelerate the degradation of cattle dung on pastures. Exotic in North America, all three species have expanded their distributions since their introduction onto the continent. Here we report development of CLIMEX®bioclimatic models using data collected before 2011 that predict the eventual North American distributions of these species. Data collected after 2010 is used to validate these models. Model outputs identify large regions of the central United States of America suitable for establishment ofO. nuchicornisandO. tauruswhere these species have not been reported. These results indicate that the latter two species may already be present in these regions and undetected, that they have yet to expand into these regions, and (or) that factors restricting migration or dispersal prevent these species from occupying these areas. Model outputs forD. gazellasuggest that the species has largely reached its predicted maximum distribution. These models can be used to aid the success of future relocation programmes elsewhere in the world and (or) to predict regions where these species are likely to spread without human intervention.
A Flux-Corrected Phase-Field Method for Surface Diffusion
Authors: Zhang Yujie , Ye Wenjing 
Published: June 2017

AbstractPhase-field methods with a degenerate mobility have been widely used to simulate surface diffusion motion. However, apart from the motion induced by surface diffusion, adverse effects such as shrinkage, coarsening and false merging have been observed in the results obtained from the current phase-field methods, which largely affect the accuracy and numerical stability of these methods. In this paper, a flux-corrected phase-field method is proposed to improve the performance of phase-field methods for simulating surface diffusion. The three effects were numerically studied for the proposed method and compared with those observed in the two existing methods, the original phase-field method and the profile-corrected phase-field method. Results show that compared to the original phase-field method, the shrinkage effect in the profile-corrected phase-field method has been significantly reduced. However, coarsening and false merging effects still present and can be significant in some cases. The flux-corrected phase field performs the best in terms of eliminating the shrinkage and coarsening effects. The false merging effect still exists when the diffuse regions of different interfaces overlap with each other. But it has been much reduced as compared to that in the other two methods.
A Domain Decomposition Based Spectral Collocation Method for Lane-Emden Equations
Authors: Guo Yuling , Huang Jianguo 
Published: June 2017

AbstractA domain decomposition based spectral collocation method is proposed for numerically solving Lane-Emden equations, which are frequently encountered in mathematical physics and astrophysics. Compared with the existing methods, this method requires less computational cost and is particularly suitable for long-term computation. The related error estimates are also established, indicating the spectral accuracy of the method. The numerical performance and efficiency of the method are illustrated by several numerical experiments.
Exponential Time Differencing Gauge Method for Incompressible Viscous Flows
Authors: Ju Lili , Wang Zhu 
Published: June 2017

AbstractIn this paper, we study an exponential time differencing method for solving the gauge system of incompressible viscous flows governed by Stokes or Navier-Stokes equations. The momentum equation is decoupled from the kinematic equation at a discrete level and is then solved by exponential time stepping multistep schemes in our approach. We analyze the stability of the proposed method and rigorously prove that the first order exponential time differencing scheme is unconditionally stable for the Stokes problem. We also present a compact representation of the algorithm for problems on rectangular domains, which makes FFT-based solvers available for the resulting fully discretized system. Various numerical experiments in two and three dimensional spaces are carried out to demonstrate the accuracy and stability of the proposed method.
Observational evidence of 3‐D cloud effects in OCO‐2 CO2 retrievals
Authors: Massie Steven T. , Sebastian Schmidt K. , Eldering Annmarie , Crisp David 
Published: June 2017

AbstractThe standard deviations of the distributions of Orbiting Carbon Observatory (OCO‐2) measurements of CO2 (i.e., XCO2) increase in size in the presence of clouds. XCO2 and Moderate Resolution Imaging Spectroradiometer (MODIS) radiance and cloud fields, and OCO‐2 A‐band radiances, are analyzed in order to determine if this behavior is best described as a radiance‐level retrieval artifact or by 3‐D radiative transfer effects. Observations in clear‐sky and fair weather cumulus scenes are analyzed. Scatter diagrams of XCO2 versus MODIS (and OCO‐2) radiances are presented, and averages are calculated for each scene for several radiance bins. The averages vary little in clear skies but decrease markedly for cloudy scenes as radiances increase. These decreases are consistent with an interpretative framework provided by 3‐D SHDOM radiative transfer calculations. Two 3‐D metrics, ΔXCO2 and Have, are calculated and applied. ΔXCO2 is the difference in XCO2 for the smallest and largest radiance bins. Have is a measure of the heterogeneity of the cloud radiance field. Lines of XCO2 and MODIS radiance for four target mode scenes have different slopes for clear and cloudy scenes, contrary to the radiance‐level retrieval artifact interpretation. In contrast, the graph of ΔXCO2 and MODIS Have for the various scenes has a linear correlation coefficient of 0.92, consistent with the 3‐D interpretation. Since the OCO‐2 measurement requirement is 1 ppmv, the cloudy scene XCO2 standard deviations between 1.2 and 2.6 ppmv indicate that 3‐D cloud effects add an important component to the XCO2 error budget.
Rock friction under variable normal stress
Authors: Kilgore Brian , Beeler N. M. , Lozos Julian , Oglesby David 
Published: June 2017

AbstractThis study is to determine the detailed response of shear strength and other fault properties to changes in normal stress at room temperature using dry initially bare rock surfaces of granite at normal stresses between 5 and 7 MPa. Rapid normal stress changes result in gradual, approximately exponential changes in shear resistance with fault slip. The characteristic length of the exponential change is similar for both increases and decreases in normal stress. In contrast, changes in fault normal displacement and the amplitude of small high‐frequency elastic waves transmitted across the surface follow a two stage response consisting of a large immediate and a smaller gradual response with slip. The characteristic slip distance of the small gradual response is significantly smaller than that of shear resistance. The stability of sliding in response to large step decreases in normal stress is well predicted using the shear resistance slip length observed in step increases. Analysis of the shear resistance and slip‐time histories suggest nearly immediate changes in strength occur in response to rapid changes in normal stress; these are manifested as an immediate change in slip speed. These changes in slip speed can be qualitatively accounted for using a rate‐independent strength model. Collectively, the observations and model show that acceleration or deceleration in response to normal stress change depends on the size of the change, the frictional characteristics of the fault surface, and the elastic properties of the loading system.
Sea‐to‐air flux of dimethyl sulfide in the South and North Pacific Ocean as measured by proton transfer reaction‐mass spectrometry coupled with the gradient flux technique
Authors: Omori Yuko , Tanimoto Hiroshi , Inomata Satoshi , Ikeda Kohei , Iwata Toru , Kameyama Sohiko , Uematsu Mitsuo , Gamo Toshitaka , Ogawa Hiroshi , Furuya Ken 
Published: June 2017

AbstractExchange of dimethyl sulfide (DMS) between the surface ocean and the lower atmosphere was examined by using proton transfer reaction‐mass spectrometry coupled with the gradient flux (PTR‐MS/GF) system. We deployed the PTR‐MS/GF system and observed vertical gradients of atmospheric DMS just above the sea surface in the subtropical and transitional South Pacific Ocean and the subarctic North Pacific Ocean. In total, we obtained 370 in situ profiles, and of these we used 46 data sets to calculate the sea‐to‐air flux of DMS. The DMS flux determined was in the range from 1.9 to 31 μmol m−2 d−1 and increased with wind speed and biological activity, in reasonable accordance with previous observations in the open ocean. The gas transfer velocity of DMS derived from the PTR‐MS/GF measurements was similar to either that of DMS determined by the eddy covariance technique or that of insoluble gases derived from the dual tracer experiments, depending on the observation sites located in different geographic regions. When atmospheric conditions were strongly stable during the daytime in the subtropical ocean, the PTR‐MS/GF observations captured a daytime versus nighttime difference in DMS mixing ratios in the surface air overlying the ocean surface. The difference was mainly due to the sea‐to‐air DMS emissions and stable atmospheric conditions, thus affecting the gradient of DMS. This indicates that the DMS gradient is strongly controlled by diurnal variations in the vertical structure of the lower atmosphere above the ocean surface.
Modeling geomagnetic induced currents in Australian power networks
Authors: Marshall R. A. , Kelly A. , Van Der Walt T. , Honecker A. , Ong C. , Mikkelsen D. , Spierings A. , Ivanovich G. , Yoshikawa A. 
Published: June 2017

AbstractGeomagnetic induced currents (GICs) have been considered an issue for high‐latitude power networks for some decades. More recently, GICs have been observed and studied in power networks located in lower latitude regions. This paper presents the results of a model aimed at predicting and understanding the impact of geomagnetic storms on power networks in Australia, with particular focus on the Queensland and Tasmanian networks. The model incorporates a “geoelectric field” determined using a plane wave magnetic field incident on a uniform conducting Earth, and the network model developed by Lehtinen and Pirjola (1985). Model results for two intense geomagnetic storms of solar cycle 24 are compared with transformer neutral monitors at three locations within the Queensland network and one location within the Tasmanian network. The model is then used to assess the impacts of the superintense geomagnetic storm of 29–31 October 2003 on the flow of GICs within these networks. The model results show good correlation with the observations with coefficients ranging from 0.73 to 0.96 across the observing sites. For Queensland, modeled GIC magnitudes during the superstorm of 29–31 October 2003 exceed 40 A with the larger GICs occurring in the south‐east section of the network. Modeled GICs in Tasmania for the same storm do not exceed 30 A. The larger distance spans and general east‐west alignment of the southern section of the Queensland network, in conjunction with some relatively low branch resistance values, result in larger modeled GICs despite Queensland being a lower latitude network than Tasmania.
Full Selectivity Control in Cobalt(III)‐Catalyzed C−H Alkylations by Switching of the C−H Activation Mechanism
Authors: Zell Daniel , Bursch Markus , Müller Valentin , Grimme Stefan , Ackermann Lutz 
Published: June 2017

AbstractSelectivity control in hydroarylation‐based C−H alkylation has been dominated by steric interactions. A conceptually distinct strategy that exploits the programmed switch in the C−H activation mechanism by means of cobalt catalysis is presented, which sets the stage for convenient C−H alkylations with unactivated alkenes. Detailed mechanistic studies provide compelling evidence for a programmable switch in the C−H activation mechanism from a linear‐selective ligand‐to‐ligand hydrogen transfer to a branched‐selective base‐assisted internal electrophilic‐type substitution.
Spectroscopic Observation of the Triplet Diradical State of a Cyclobutadiene
Authors: Kostenko Arseni , Tumanskii Boris , Kobayashi Yuzuru , Nakamoto Masaaki , Sekiguchi Akira , Apeloig Yitzhak 
Published: June 2017

AbstractTetrakis(trimethylsilyl)cyclobuta‐1,3‐diene (1) was subjected to a temperature‐dependent EPR study to allow the first spectroscopic observation of a triplet diradical state of a cyclobutadiene (2). From the temperature dependent EPR absorption area we derive a singlet→triplet (1→2) energy gap, EST, of 13.9 kcal mol−1, in agreement with calculated values. The zero‐field splitting parameters D=0.171 cm−1, E=0 cm−1 are accurately reproduced by DFT calculations. The triplet diradical 2 is thermally accessible at moderate temperatures. It is not an intermediate in the thermal cycloreversion of cyclobutadiene to two acetylene molecules.
Selective and Tunable Near‐Infrared and Visible Light Transmittance of MoO3−x Nanocomposites with Different Crystallinity
Authors: Li Ning , Li Yamei , Sun Guangyao , Ma Yining , Chang Tianci , Ji Shidong , Yao Heliang , Cao Xun , Bao Shanhu , Jin Ping 
Published: June 2017

AbstractIn this Communication, we report MoO3−x nanocomposites in which the near‐infrared and visible light transmittance can be selectively modulated through the crystallinity. The MoO3−x nanocomposites were fabricated by a hydrothermal method, and their optical properties were characterized by UV‐Vis spectrometer. The obtained results proved the possibility to tune the nanocomposite's optical properties in the UV/Visible spectral region: crystalline MoO3 mainly regulates the near‐infrared range (800–2600 nm), and amorphous MoO3−x mainly changes the visible range from 350 nm to 800 nm and MoO3−x, with semi‐crystalline structures mainly modulating around 800–1000 nm. These kinds of optical modulations could be attributed to small polar absorption, free electron absorption and plasmon absorption according to different crystallinity. Our work may create new possibilities for future applications such as photochromism, photocatalysis, and electrochromism.
Maternal Smoking, Alcohol, and Caffeine Exposures and Risk of Hypospadias
Authors: Carmichael Suzan L. , Ma Chen , Shaw Gary M. ,   the National Birth Defects Prevention Study
Published: June 2017

BackgroundWe examined the association of hypospadias risk with maternal smoking and consumption of alcohol and caffeine.MethodsWe analyzed data from mothers of 2437 moderate/severe cases and 5472 nonmalformed controls born from 1997 to 2011 who participated in the National Birth Defects Prevention Study (NBDPS). Exposures were assessed by maternal telephone interviews. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) adjusted for mother's age, parity, race‐ethnicity, education, vitamin/mineral supplement intake, obesity, and study center.ResultsActive smoking during the first month of pregnancy was associated with reduced risk, with smaller ORs for increasing quantity smoked; the OR for smoking >1/2 pack/day was 0.7 (95% CI, 0.5–0.9). Among nonsmokers, the OR for any secondhand smoke exposure was 0.8 (95% CI, 0.7–0.9). ORs for alcohol and caffeine consumption were near one and CIs included 1.0. In an analysis of joint exposures to smoking and alcohol and caffeine consumption, the only OR for which the 95% CI excluded 1.0 was for women who smoked, drank, and had low caffeine consumption (OR, 0.6; 95% CI, 0.4–0.8).ConclusionMaternal exposure to cigarette smoke was associated with reduced risk, and women who smoked, drank, and had low caffeine intake were at lowest risk. We do not interpret these results to suggest that these exposures have overall benefit to a pregnant woman or developing fetus. They may, however, offer clues to help us understand mechanisms that lead to hypospadias. Birth Defects Research 109:1127–1133, 2017. © 2017 Wiley Periodicals, Inc.
Chemical Composition and Allelopathic, Antibacterial, Antifungal, and Antiacetylcholinesterase Activity of Fish‐mint (Houttuynia cordataThunb.) from India
Authors: Verma Ram S. , Joshi Neeta , Padalia Rajendra C. , Singh Ved R. , Goswami Prakash , Kumar Ajay , Iqbal Hina , Verma Rajesh K. , Chanda Debabrata , Chauhan Amit , Saikia Dharmendra 
Published: June 2017

Fish‐mint (Houttuynia cordataThunb.), belonging to family Saururaceae, has long been used as food and traditional herbal medicine. The present study was framed to assess the changes occurring in the essential‐oil composition of H. cordata during annual growth and to evaluate allelopathic, antibacterial, antifungal, and antiacetylcholinesterase activities. The essential‐oil content ranged from 0.06 – 0.14% and 0.08 – 0.16% in aerial parts and underground stem, respectively. The essential oils were analysed by GC‐FID, GC/MS, and NMR (1H and 13C). Major constituents of aerial‐parts oil was 2‐undecanone (19.4 – 56.3%), myrcene (2.6 – 44.3%), ethyl decanoate (0.0 – 10.6%), ethyl dodecanoate (1.1 – 8.6%), 2‐tridecanone (0.5 – 8.3%), and decanal (1.1 – 6.9%). However, major constituents of underground‐stem oil were 2‐undecanone (29.5 – 42.3%), myrcene (14.4 – 20.8%), sabinene (6.0 – 11.1%), 2‐tridecanone (1.8 – 10.5%), β‐pinene (5.3 – 10.0%), and ethyl dodecanoate (0.8 – 7.3%). Cluster analysis revealed that essential‐oil composition varied substantially due to the plant parts and season of collection. The oils exhibited significant allelopathic (inhibition: 77.8 – 88.8%; LD50: 2.45 – 3.05 μl/plate), antibacterial (MIC: 0.52 – 2.08 μl/ml; MBC: bacteriostatic) and antifungal (MIC: 2.08 – 33.33 μl/ml; MFC: 4.16 – 33.33 μl/ml) activities. The results indicate that the essential oil from H. cordata has a significant potential to allow future exploration and exploitation as a natural antimicrobial and allelopathic agent.
Aberrant coronary artery spasms cause ST‐T segment depression during endovascular ablation of atrial flutter
Authors: Lanters Eva A. H. , Coenen Adriaan , Lubbers Marisa M. , Nieman Koen , de Groot Natasja M. S. 
Published: June 2017

Key Clinical MessageST‐T segment depression during right‐sided endovascular catheter ablation is not only caused by obstructive coronary artery disease or (induced) tachycardia. Clinicians should also consider coronary artery spasms evoked by manipulation of nearby catheters, especially in patients with abnormal coronary artery anatomy.
Core‐shell NiCo2S4@MnMoO4 as an Advanced Electrode Material for High‐performance Electrochemical Energy Storage
Authors: Wei Xijun , Li Yanhong , Peng Huarong , Liu Chunli , Zhang Yunhuai , Xiao Peng 
Published: June 2017

AbstractHierarchical NiCo2S4@MnMoO4 core‐shell structure composites are first designed and fabricated through a three‐step hydrothermal process. NiCo2S4 microspheres consisting of nanotubes are utilized as ideal conductive scaffolds, whereas ultrathin MnMoO4 nanosheets are controllably deposited. This particular structure is beneficial to the migration and diffusion of ions, meaning that the redox reactions of the active materials can be carried out quickly and completely. The NiCo2S4@MnMoO4 hybrid electrode shows an ultrahigh specific capacitance of 1186.44 F g−1 at a current density of 1 A g−1 (3.6 F cm−2 at 3 mA cm−2). It exhibits good cycling stability with 90.1 % capacitance retention over 5000 cycles at 10 A g−1. Moreover, an electrochemical energy‐storage device is fabricated, where the as‐prepared NiCo2S4@MnMoO4 is employed as both the cathode and anode. The device achieves a high energy density of 47.8 Wh kg−1 at a power density of 699.9 W kg−1, as well as excellent cycling stability (88.3 % capacitance retention over 5000 cycles at 10 A g−1). The outstanding performance demonstrates that the NiCo2S4@MnMoO4 core−shell composite is a promising electrode material for electrochemical energy storage, which may inspire researchers to continue investigating heterostructured materials as energy‐storage materials.
Solvent‐Templated Electrodeposition of Mesoporous Nickel Oxide Layers for Solar Cell Applications
Authors: Koussi‐Daoud Sana , Planchat Aurélien , Renaud Adèle , Pellegrin Yann , Odobel Fabrice , Pauporté Thierry 
Published: June 2017

AbstractSolvent engineering for the electrochemical preparation of porous, thick, and adherent nickel oxide layers is investigated. The deposition of this oxide is studied in pure aprotic dimethyl sulfoxide (DMSO) medium and in DMSO/water mixtures through the cathodic reduction of a nickel nitrate precursor. In pure DMSO, the as‐grown layers were a mixture of directly obtained NiO and metallic nickel. On the other hand, in the presence of water, β‐Ni(OH)2 and Ni° mixed layers were formed. In the absence of water or at low water contents, we show that the solvent is included in the layer. After annealing at a sufficient temperature to eliminate DMSO, pores are released and mesoporous films are formed. These solvent‐templated electrodeposited layers have been applied in p‐type dye‐sensitized solar cells (p‐DSSCs) after sensitization by the P1 dye. For high water content (25 vol.%), the electrodeposited layers were non‐porous and were consequently unsuitable for p‐DSSC application.
Cobalt‐Catalyzed ortho‐C−H Functionalization/Alkyne Annulation of Benzylamine Derivatives: Access to Dihydroisoquinolines
Authors: Martínez Ángel Manu , Rodríguez Nuria , Gómez‐Arrayás Ramón , Carretero Juan C. 
Published: June 2017

AbstractA practical picolinamide‐directed C−H functionalization/alkyne annulation of benzylamine derivatives enabling access to the previously elusive 1,4‐dihydroisoquinoline skeleton was developed using molecular O2 as the sole oxidant and Co(OAc)2 as precatalyst. The method is compatible with both internal and terminal alkynes and shows high versatility and functional‐group tolerance. Furthermore, full preservation of enantiopurity is observed when using non‐racemic α‐substituted benzylamine derivatives. Kinetic analysis of the reagents and catalyst, labeling experiments, and the isolation and identification of catalytically competent Co‐complexes revealed important insights about the mechanism.