bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seasonal eddy kinetic energy modulations along the North Equatorial Countercurrent in the western Pacific
Authors: Chen Xiao , Qiu Bo , Chen Shuiming , Qi Yiquan , Du Yan 
Published: September 2015

AbstractSeasonal eddy kinetic energy (EKE) variability and its associated eddy energy conversion processes in the western tropical Pacific are investigated using satellite altimeter observations and a global, eddy‐resolving, ocean general circulation model (OGCM). Both the altimeter‐observed sea surface height anomalies and the OGCM simulation show an area with enhanced EKE east of the Mindanao Island centered around 133°E and 5°N. This enhanced EKE area corresponds to the location of the quasi‐stationary meander of the North Equatorial Countercurrent (NECC) and is bordered to the south by the Halmahera Eddy. The mesoscale EKE in this area exhibits a clear seasonality, strong in summer (July–August) and weak in winter (November–January), and much of this seasonality is confined to the upper 200 m layer. An investigation into the upper ocean eddy energetics based on the OGCM simulation reveals that the areal barotropic eddy energy conversion rate has an annual cycle similar to the EKE variations, while the areal baroclinic eddy energy conversion is found to be much smaller that the barotropic conversion rate and exhibits no clear seasonal changes. This indicates that the EKE variations are largely controlled by barotropic conversion of the seasonally varying regional circulation. By examining the seasonal background circulation changes, we find that the amplification of the barotropic eddy energy conversion rate in July–August is related to the seasonal evolution of the Mindanao Current and the New Guinea Coastal Current that amplifies the curvature and amplitude of the quasi‐stationary meander of the NECC and results in an elevated EKE level through increased regional barotropic conversion.
Observed enhanced internal tides in winter near the Luzon Strait
Authors: Liu Junliang , He Yinghui , Wang Dongxiao , Liu Tongya , Cai Shuqun 
Published: September 2015

AbstractSeasonal characteristics and nonlinear interaction of internal tides (ITs) near the Luzon Strait in the northeastern South China Sea are investigated using 285 day, in situ observation data. It is found that ITs, which are dominated by the first‐mode wave throughout the year, are the strongest in subsurface layer. Baroclinic incoherent diurnal (semidiurnal) variance accounts for about 85.7% (78.3%) of diurnal (semidiurnal) ITs. The amplitude and seasonal variation of the diurnal ITs are more prominent than those that are semidiurnal, e.g., the largest kinetic energy densities of diurnal and semidiurnal baroclinic tidal currents are 2.81 and 0.83 KJ/m2 in winter, respectively. It is considered that there are two reasons for the significantly enhanced ITs in winter: (1) it may be due to the Kuroshio intrusion, and (2) the enhanced diurnal ITs may be due to the enhanced diurnal barotropic tidal currents, while the enhanced semidiurnal ITs may be caused by the strong nonlinear interaction between diurnal IT constituents O1 and K1 due to their high vertical shears in subsurface layer. Thus, harmonic semidiurnal constituent D2 with a similar frequency of constituent M2 is induced; it subsequently enhances the semidiurnal ITs in this subsurface layer, and the associated energy is carried downward to enhance the semidiurnal ITs in the upper and lower layers.
An analytical study on artesian flow conditions in unconfined‐aquifer drainage basins
Authors: Wang Jun‐Zhi , Jiang Xiao‐Wei , Wan Li , Wörman Anders , Wang Heng , Wang Xu‐Sheng , Li Hailong 
Published: September 2015

AbstractAlthough it has been reported that flowing artesian wells could be topographically controlled, there is no quantitative research on artesian flow conditions in unconfined aquifers. In this study, the water table, which has a lower amplitude than the land surface, is damped from the topography and used as the boundary condition to obtain the analytical solution of hydraulic head of a unit basin with a single flow system. The term artesian head is defined to characterize the condition of flowing artesian wells. The zone with positive artesian head is called artesian zone while with negative artesian head is nonartesian zone. The maximum artesian head and the size of artesian zones are found to increase with the damping factor and the anisotropy ratio, and decrease with the ratio of basin width to depth and the depth‐decay exponent of hydraulic conductivity. Moreover, the artesian head increases with depth nearby the valley and decreases with depth near by the divide, and the variation rates are influenced by the decay exponent and the anisotropy ratio. Finally, the distribution of flowing artesian wells and the artesian head measurements in different depths of a borehole in a small catchment in the Ordos Plateau, Northwestern China is used to illustrate the theoretical findings. The change in artesian head with depth was used to estimate the anisotropy ratio and the decay exponent. This study opens up a new door to analyze basin‐scale groundwater flow.
Lasers, Extreme UV, and Soft X‐ray
Authors: Nilsen Joseph 
Published: September 2015

AbstractThree decades ago, large ICF lasers that occupied entire buildings were used as the energy sources to drive the first X‐ray lasers. Today, X‐ray lasers are tabletop, spatially coherent, high‐repetition rate lasers that enable many of the standard optical techniques such as interferometry to be extended to the soft X‐ray regime between wavelengths of 10 and 50 nm. Over the past decade, X‐ray laser performance has been improved by the use of the grazing incidence geometry, diode‐pumped solid‐state lasers, and seeding techniques. The dominant X‐ray laser schemes are the monopole collisional excitation lasers either driven by chirped pulse amplification (CPA) laser systems or capillary discharge. The CPA systems drive lasing in neon‐like or nickel‐like ions, typically in the 10–30 nm range, while the capillary system works best for neon‐like argon at 46.9 nm. Most researchers use nickel‐like ion lasers near 14 nm because they are well matched to the Mo:Si multilayer mirrors that have peak reflectivity near 13 nm and are used in many applications. The past decade has seen the birth of the X‐ray free electron laser (XFEL) that can reach wavelengths down to 0.1 nm and the inner‐shell Ne laser at 1.46 nm.
Changing Breathability of Polyethylene Composite Films with Different Porous Structures Depending on Stretching Processes
Authors: Özen İlhan , Şİmşek Süleyman 
Published: September 2015

ABSTRACTThe aim of this work is to investigate the effects of different stretching processes on breathability performance of linear low‐density polyethylene (LLDPE)/coated calcium carbonate (CaCO3) composite films under the same conditions. Coated calcium carbonates and powdered LLDPE were physically mixed and dried in a high shear mixer, and polymer compounds containing 45 and 55 wt% coated calcium carbonate were generated using a twin screw extruder. Cast films were produced and then they were stretched 3.5 times in machine direction at 25°C by using stenter and interdigitation stretching methods. It was revealed that not only the CaCO3 type and loading amount but also the stretching type has an enormous effect on breathability performance. In addition, the quality of porosity, that is, the amount of interconnecting pores, was determined to play an important role in breathability. And, the interdigitation stretching process offers the potential for a better breathability at reduced processing costs.
Necrolemur anadoni, a new species of Microchoerinae (Omomyidae, Primates) from the Middle Eocene of Sant Jaume de Frontanyà (Pyrenees, Northeastern Spain)
Authors: Minwer‐Barakat Raef , Marigó Judit , Moyà‐Solà Salvador 
Published: September 2015

ABSTRACTObjectivesThe material of Necrolemur (Microchoerinae, Omomyidae, Primates) from the Middle Eocene (Robiacian) locality of Sant Jaume de Frontanyà (Eastern Pyrenees) is described. This is the first confirmable record of this genus from Spain.MethodsA mandible fragment bearing P4‐M3 and 15 isolated teeth have been carefully described and compared with all the known species of Necrolemur (namely Necrolemur antiquus, Necrolemur zitteli and Necrolemur cf. zitteli from Egerkingen α) and with Nannopithex filholi.ResultsThe studied material shows substantial differences from all previously described forms of Necrolemur and can be erected as a new species. Necrolemur anadoni sp. nov. is characterized by its small size, weak enamel wrinkling, lower molars with the trigonid significantly narrower than the talonid, distinct paraconid in the M1 but poorly differentiated M2 and M3 paraconids, relatively short M3 hypoconulid lobe, M1‐2 with tubercular buccal metaconule, crest‐shaped lingual metaconule, hypocone connected to the protocone by a weak postprotocingulum, and M3 with a very reduced talon basin. It exhibits intermediate size and morphological features between the older Nannopithex filholi and the more recent Necrolemur antiquus.ConclusionsThis finding allows reinterpretation of the phylogenetic relationships of the known species of Necrolemur. Necrolemur anadoni is considered a direct descendant of Nannopithex filholi and the ancestor of Necrolemur antiquus, whereas Necrolemur zitteli would be a descendant of N. antiquus. Finally, Necrolemur cf. zitteli from Egerkingen most likely evolved independently from N. filholi, being thus separated from the N. filholi‐N. anadoni‐N. antiquus lineage. Am J Phys Anthropol 158:730–744, 2015. © 2015 Wiley Periodicals, Inc.
Difluorocarbene‐Derived Trifluoromethylthiolation and [18F]Trifluoromethylthiolation of Aliphatic Electrophiles
Authors: Zheng Jian , Wang Lu , Lin Jin‐Hong , Xiao Ji‐Chang , Liang Steven H. 
Published: September 2015

AbstractThe first trifluoromethylthiolation and [18F]trifluoromethylthiolation of alkyl electrophiles with in situ generated difluorocarbene in the presence of elemental sulfur and external (radioactive) fluoride ion is described. This transition‐metal‐free approach is high yielding, compatible with a variety of functional groups, and operated under mild reaction conditions. The conceptual advantage of this exogenous‐fluoride‐mediated transformation enables unprecedented syntheses of [18F]CF3S‐labeled molecules from most commonly used [18F]fluoride ions. The rapid radiochemical reaction time (≤1 min) and high functional‐group tolerance allow access to a variety of aliphatic [18F]CF3S compounds in high yields.
Self‐Assembled Asymmetric Block Copolymer Membranes: Bridging the Gap from Ultra‐ to Nanofiltration
Authors: Yu Haizhou , Qiu Xiaoyan , Moreno Nicolas , Ma Zengwei , Calo Victor Manuel , Nunes Suzana P. , Peinemann Klaus‐Viktor 
Published: September 2015

AbstractThe self‐assembly of block copolymers is an emerging strategy to produce isoporous ultrafiltration membranes. However, thus far, it has not been possible to bridge the gap from ultra‐ to nanofiltration and decrease the pore size of self‐assembled block copolymer membranes to below 5 nm without post‐treatment. It is now reported that the self‐assembly of blends of two chemically interacting copolymers can lead to highly porous membranes with pore diameters as small as 1.5 nm. The membrane containing an ultraporous, 60 nm thin separation layer can fully reject solutes with molecular weights of 600 g mol−1 in aqueous solutions with a water flux that is more than one order of magnitude higher than the permeance of commercial nanofiltration membranes. Simulations of the membrane formation process by dissipative particle dynamics (DPD) were used to explain the dramatic observed pore size reduction combined with an increase in water flux.
Gold(I)‐Catalyzed Addition of Silylacetylenes to Acylsilanes: Synthesis of Indanones by CH Functionalization through a Gold(I) Carbenoid
Authors: González Jairo , Santamaría Javier , Ballesteros Alfredo 
Published: September 2015

AbstractA gold(I)‐catalyzed synthesis of indanones from trimethylsilylacetylenes and acylsilanes is presented. The reaction is initiated through a synergistic acylsilane activation–gold acetylide formation and involves consecutive alkyne σ‐gold(I) addition, π‐activation, and 1,2‐migration of a silyl group. Studies performed on the reaction mechanism allowed to establish the nature of the silyl migrating group and invoke the participation of a gold(I) carbenoid intermediate. The reaction is completed by a gold(I) CH functionalization step.
N‐Heterocyclic Carbene Catalyzed Oxidative Coupling of Alkenes/ α‐Bromoacetophenones with Aldehydes: A Facile Entry to α,β‐Epoxy Ketones
Authors: Reddi Rambabu N. , Prasad Pragati K. , Sudalai Arumugam 
Published: September 2015

AbstractA novel, N‐heterocyclic carbene (NHC) catalyzed direct oxidative coupling of styrenes with aldehydes has been described for the synthesis of α,β‐epoxy ketones in good yields. This unprecedented regioselective oxidative coupling employs NBS/DBU/DMSO (DBU=1,8‐diazabicyclo [5.4. 0] undec‐7‐ene, DMSO=dimethylsulfoxide, NBS=N‐bromosuccinimide) as an oxidative system at ambient conditions. Additionally, first NHC‐catalyzed Darzens reaction of α‐bromoketones and aldehydes under mild reaction conditions has also been described. Interestingly, mechanistic studies have revealed the preferred reactivity of NHC with alkene/α‐bromoketone rather than aldehydes, thus proceeding via the ketodeoxy Breslow intermediate.
Oxidative Dehydrogenation on Nanocarbon: Intrinsic Catalytic Activity and Structure–Function Relationships
Authors: Qi Wei , Liu Wei , Guo Xiaoling , Schlögl Robert , Su Dangsheng 
Published: September 2015

AbstractPhysical and chemical insights into the nature and quantity of the active sites and the intrinsic catalytic activity of nanocarbon materials in alkane oxidative dehydrogenation (ODH) reactions are reported using a novel in situ chemical titration process. A study on the structure–function relationship reveals that the active sites are identical both in nature and function on various nanocarbon catalysts. Additionally, the quantity of the active sites could be used as a metric to normalize the reaction rates, and thus to evaluate the intrinsic activity of nanocarbon catalysts. The morphology of the nanocarbon catalysts at the microscopic scale exhibits a minor influence on their intrinsic ODH catalytic activity. The number of active sites calculated from the titration process indicates the number of catalytic centers that are active (that is, working) under the reaction conditions.
Polyether‐based main‐chain‐type polytriazole elastomer with benzoxazine via a 1,3‐dipolar cycloaddition reaction
Authors: Wan Liqiang , Han Dongjin , Liu Qiang , Xu Zhongyi , Huang Farong 
Published: September 2015

ABSTRACTA novel functional polyether‐based elastomer with a benzoxazine structure in its main chain was successfully synthesized via a 1,3‐dipolar cycloaddition reaction. Benefitting from a facile one‐pot synthesis strategy, the elastomer was prepared at low temperature (80°C) and was characterized clearly afterward. The azide‐terminated polyether and acetylene‐terminated benzoxazine were used as the soft and hard segments, respectively, in the polymer chain. Because the triazole rings served as stable linkage between the soft and hard segments, the elastomer possessed good thermal stability (the 5% weight loss temperature could exceed 350°C) compared to traditional elastomers, such as polyurethane. The rigid benzoxazine rings provided the product with good mechanical properties (the tensile strength of the elastomer could exceed 30 MPa). Furthermore, the ring‐opening polymerization of oxazine rings in the structure gifted the elastomer with possibility of thermally induced structural transformation. The thermally induced structural transformation could conveniently realize the conversion of the elastomer to a thermosetting resin. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 132, 42820.
Low‐dose maternal warfarin intake resulting in fetal warfarin syndrome: In search for a safe anticoagulant regimen during pregnancy
Authors: Basu Sriparna , Aggarwal Priyanka , Kakani Neha , Kumar Ashok 
Published: September 2015

BackgroundFetal exposure to maternal ingestion of warfarin is known to produce certain dysmorphic features in the neonate, known as fetal warfarin syndrome (FWS). There is a general consensus that maternal intake of warfarin at a daily dose of 5 mg or less is safe both for the infant and the mother.MethodsWe report four cases of FWS born to mothers with rheumatic heart disease on warfarin prophylaxis during pregnancy at a dose less than 5 mg/day.ResultsAlong with typical facial features of FWS and multiple epiphyseal stippling in skeletal x‐ray, Case 1 had Dandy‐Walker malformation and Case 2 had laryngo‐tracheomalacia and patent ductus arteriosus.ConclusionWe emphasize the need for optimizing the choice and dosage schedule of anticoagulants during pregnancy, least harmful for the mother and her developing fetus. Birth Defects Research (Part A) 106:142–147, 2016. © 2015 Wiley Periodicals, Inc.
Fluorescent bovine serum albumin interacting with the antitussive quencher dextromethorphan: a spectroscopic insight
Authors: Durgannavar Amar K. , Patgar Manjanath B. , Nandibewoor Sharanappa T. , Chimatadar Shivamurti A. 
Published: September 2015

AbstractThe interaction of dextromethorphan hydrobromide (DXM) with bovine serum albumin (BSA) is studied by using fluorescence spectra, UV–vis absorption, synchronous fluorescence spectra (SFS), 3D fluorescence spectra, Fourier transform infrared (FTIR) spectroscopy and circular dichroism under simulated physiological conditions. DXM effectively quenched the intrinsic fluorescence of BSA. Values of the binding constant, KA, are 7.159 × 103, 9.398 × 103 and 16.101 × 103 L/mol; the number of binding sites, n, and the corresponding thermodynamic parameters ΔG°, ΔH° and ΔS° between DXM and BSA were calculated at different temperatures. The interaction between DXM and BSA occurs through dynamic quenching and the effect of DXM on the conformation of BSA was analyzed using SFS. The average binding distance, r, between the donor (BSA) and acceptor (DXM) was determined based on Förster's theory. The results of fluorescence spectra, UV–vis absorption spectra and SFS show that the secondary structure of the protein has been changed in the presence of DXM. Copyright © 2015 John Wiley & Sons, Ltd.
Crystallographic Investigation of Imidazolium Ionic Liquid Effects on Enzyme Structure
Authors: Nordwald Erik M. , Plaks Joseph G. , Snell Jared R. , Sousa Marcelo C. , Kaar Joel L. 
Published: September 2015

AbstractWe present the first crystallographic insight into the interactions of an ionic liquid (IL) with an enzyme, which has widespread implications for stabilizing enzymes in IL media for biocatalysis. Structures of Bacillus subtilis lipase A (lipA) and an IL‐stable variant (QM‐lipA) were obtained in the presence of increasing concentrations of 1‐butyl‐3‐methylimidazolium chloride ([BMIM][Cl]). These studies revealed that the [BMIM] cation interacts with surface residues through hydrophobic and cation–π interactions. Of specific interest was the disruption of internal stacking interactions of aromatic side chains by [BMIM], which provides structural evidence for the mechanism of enzyme denaturation by ILs. The interaction of [BMIM] and Cl ions with lipA was reduced by the stabilizing mutations Y49E and G158E in QM‐lipA. Ultimately, these findings present the molecular basis for stabilizing enzymes from IL‐induced inactivation, as well as the selection of ILs that are less denaturing.
The Cage Structure of IndanCHF3 is Based on the Cooperative Effects of CH⋅⋅⋅π and CH⋅⋅⋅F Weak Hydrogen Bonds
Authors: Favero Laura B. , Li Weixing , Spada Lorenzo , Evangelisti Luca , Visentin Giorgio , Caminati Walther 
Published: September 2015

AbstractThe structural and energetic features of the CH⋅⋅⋅π interaction and the internal dynamics of the CHF3 group change drastically in going from benzeneCHF3 to indanCHF3, according to the analysis of the rotational spectrum of the latter complex generated in a supersonic expansion.
A Palette of Fluorescent Thiophene‐Based Ligands for the Identification of Protein Aggregates
Authors: Shirani Hamid , Linares Mathieu , Sigurdson Christina J. , Lindgren Mikael , Norman Patrick , Nilsson K. Peter R. 
Published: September 2015

AbstractBy replacing the central thiophene unit of an anionic pentameric oligothiophene with other heterocyclic moities, a palette of pentameric thiophene‐based ligands with distinct fluorescent properties were synthesized. All ligands displayed superior selectivity towards recombinant amyloid fibrils as well as disease‐associated protein aggregates in tissue sections.
Asymmetric Construction of Six‐Membered Rings by Cyclization of Allenes with Dinuclear Gold Catalysis
Authors: Qiu Youai , Zhou Jing , Li Junzhao , Fu Chunling , Guo Yinlong , Wang Haoyang , Ma Shengming 
Published: September 2015

AbstractA simple and efficient method for the synthesis of 1,4‐dihydroarenes by gold‐catalyzed 6‐endo cyclization of benzylic allenes has been developed. Furthermore, asymmetric hydroarylation of enantioenriched allenes has been realized to offer a practical and convergent approach to aromatic ring‐fused six‐membered cycles containing a chiral stereocenter such as 1,4‐dihydronaphthalenes, 1,4‐dihydrodibenzo[b,d]thiophenes, and 4,7‐dihydrobenzo[b]thiophenes by applying dinuclear [(dppm)Au2Cl2] [dppm=methylenebis(diphenylphosphane)] combined with AgOTf as the catalyst to ensure the high efficiency of chirality transfer. ESI‐MS has been applied to characterize some of the key reactive dinuclear gold intermediates successfully.
A domain‐specific high‐level programming model
Authors: Mansouri Farouk , Huet Sylvain , Houzet Dominque 
Published: September 2015

SummaryNowadays, computing hardware continues to move toward more parallelism and more heterogeneity, to obtain more computing power. From personal computers to supercomputers, we can find several levels of parallelism expressed by the interconnections of multi‐core and many‐core accelerators. On the other hand, computing software needs to adapt to this trend, and programmers can use parallel programming models (PPM) to fulfil this difficult task. There are different PPMs available that are based on tasks, directives, or low‐level languages or library. These offer higher or lower abstraction levels from the architecture by handling their own syntax. However, to offer an efficient PPM with a greater (additional) high‐level abstraction level while saving on performance, one idea is to restrict this to a specific domain and to adapt it to a family of applications. In the present study, we propose a high‐level PPM specific to digital signal‐processing applications. It is based on data‐flow graph models of computation, and a dynamic run‐time model of execution (StarPU). We show how the user can easily express this digital signal‐processing application and can take advantage of task, data, and graph parallelism in the implementation, to enhance the performances of targeted heterogeneous clusters composed of CPUs and different accelerators (e.g., GPU and Xeon Phi). Copyright © 2015 John Wiley & Sons, Ltd.