bluuebunny/crossref_metadata_2025_split huggingface dataset:
Iron sources and pathways into the Pacific Equatorial Undercurrent
Authors: Qin Xuerong , Menviel Laurie , Sen Gupta Alex , van Sebille Erik 
Published: September 2016

AbstractUsing a novel observationally constrained Lagrangian iron model forced by outputs from an eddy‐resolving biogeochemical ocean model, we examine the sensitivity of the Equatorial Undercurrent (EUC) iron distribution to EUC source region iron concentrations. We find that elevated iron concentrations derived from New Guinea Coastal Undercurrent (NGCU) alone is insufficient to explain the high concentrations observed in the EUC. In addition, due to the spread in transit times, interannual NGCU iron pulses are scavenged, diluted, or eroded, before reaching the eastern equatorial Pacific. With an additional iron source from the nearby New Ireland Coastal Undercurrent, EUC iron concentrations become consistent with observations. Furthermore, as both the New Guinea and New Ireland Coastal Undercurrents strengthen during El Niño, increased iron input into the EUC can enhance the iron supply into the eastern equatorial Pacific. Notably, during the 1997/1998 El Niño, this causes a simulated 30% iron increase at a 13 month lag.
Experimental evidence of reaction‐induced fracturing during olivine carbonation
Authors: Zhu Wenlu , Fusseis Florian , Lisabeth Harrison , Xing Tiange , Xiao Xianghui , De Andrade Vincent , Karato Shun‐ichiro 
Published: September 2016

AbstractMineral carbonation, a process that binds CO2 in the form of carbonates by silicate weathering, is widespread on the Earth's surface. Because of the abundance of silicate rocks and the permanence of the carbonated solids, sequestering CO2 via mineral carbonation has generated lots of interests. However, it is unclear how the fluid‐rock reaction proceeds to completion in spite of an increasing solid volume. We conducted a mineral carbonation experiment in which a sintered olivine aggregate reacted with a sodium bicarbonate solution at reservoir conditions. Time‐resolved synchrotron X‐ray microtomographic images show cracks in polygonal patterns arising in the surface layers and propagating into the interior of the olivine aggregate. The nanotomography data reveal that the incipient cracks intersect at right angles. We infer that stretching due to nonuniform volume expansion generates polygonal cracking of the surfaces. Our data shed new lights on the processes that control hydration and carbonation of peridotite.
Disentangling plasma interaction and induction signatures at Callisto: The Galileo C10 flyby
Authors: Liuzzo Lucas , Simon Sven , Feyerabend Moritz , Motschmann Uwe 
Published: September 2016

AbstractWe apply a combination of data analysis and hybrid modeling to study Callisto's interaction with Jupiter's magnetosphere during the Galileo C10 flyby on 17 September 1997. This encounter took place while Callisto was located near the center of Jupiter's current sheet. Therefore, induction in Callisto's subsurface ocean and magnetospheric field line draping around the moon's ionosphere both made nonnegligible contributions to the observed magnetic perturbations. The induction signal during C10 was obscured by plasma currents to a significant degree, in contrast to previously studied Callisto flybys. Our analysis reveals that at large distances to Callisto, its magnetic environment was dominated by field line draping, leading to the formation of Alfvén wings. Closer to the surface and in Callisto's wake, Galileo encountered a quasi‐dipolar “core region” that was partially shielded from the plasma interaction and was dominated by the induced field. When exiting this core region, the spacecraft crossed a rotational discontinuity where the magnetic field vector rotated by approximately 50°. The hybrid model is able to quantitatively explain numerous key features of the observed magnetic signatures, especially the transitions between draping‐ and dipole‐dominated regimes along the C10 trajectory. The model also reproduces the electron number density enhancement by 3–4 orders of magnitude detected in Callisto's wake, requiring a substantial ionosphere to surround the moon during C10. For flybys with nonnegligible plasma currents, comprehensive knowledge of the incident flow conditions and properties of Callisto's atmosphere is required to refine existing constraints on the subsurface ocean (conductivity, thickness, and depth) based on magnetic field data. These findings are highly relevant for the upcoming JUpiter ICy moon Explorer (JUICE) mission, which will include multiple Callisto flybys.
Physical drivers of chlorophyll variability in the open South China Sea
Authors: Zhang Wen‐Zhou , Wang Haili , Chai Fei , Qiu Guoqiang 
Published: September 2016

AbstractThe variability of chlorophyll a concentration (Chl a) in the open South China Sea (SCS) was examined using observations from two Bio‐Argo floats. During the period of September 2014 to August 2015, there was a permanent subsurface Chl a maximum (SCM) in the depth range of 48 to 96 m in the central basin of the SCS. In the northern basin, the SCM disappeared in winter, replaced by enhanced surface layer phytoplankton with high Chl a. The values of the SCM were influenced by the vertical displacement of isotherms. Strong wind forcing and surface cooling were the main physical drivers of high surface Chl a in winter. In the north, stronger wind than in the center, lower sea surface temperature (SST) than in the center, and Kuroshio water intrusion were more favorable for the upward transport of nutrient‐rich deep water. A large amount of nitrate could be advected from the Taiwan Strait and shallow continental shelf to the northern basin in winter. A combination of strong wind mixing, surface cooling, Kuroshio water intrusion, and horizontal advection caused the winter surface phytoplankton bloom in the north.
The unstable ice nucleation properties of Snomax® bacterial particles
Authors: Polen Michael , Lawlis Emily , Sullivan Ryan C. 
Published: September 2016

AbstractSnomax® is often used as a surrogate for biological ice nucleating particles (INPs) and has recently been proposed as an INP standard for evaluating ice nucleation methods. We have found the immersion freezing properties of Snomax particles to be substantially unstable, observing a loss of ice nucleation ability over months of repeated droplet freezing measurements of the same batch of Snomax stored as dry pellets in a freezer. This reflects the fragility of the most ice active large protein aggregates and presents issues for the use of Snomax as an INP standard. The ice nucleation properties we determined using a fresh Snomax batch agreed well with the recent method intercomparison from the Ice Nucleation UnIT (UNIT) project, while an older batch did not. Using an oil immersion droplet freezing technique, repeated freezes of Snomax droplets resulted in a decrease in ice nucleation ability after successive refreezes. We attribute this to the disruption or displacement of the most ice active protein aggregates that are thought to contain the ice nucleants. Partitioning of the protein aggregates from the droplet into the immersion oil that is accelerated by droplet freezing events could explain the observed decrease in freezing ability. Droplets in mineral oil or low viscosity silicone oil experienced a smaller reduction in freezing temperature than when squalene oil was used. The effect of the immersion oil may be specific to proteinaceous biological particles, and we have not observed it in nonproteinaceous materials. Caution is warranted in the use of oil immersion droplet freezing methods to determine immersion freezing properties.
An investigation on how inner‐core structures obtained through radar data assimilation affect track forecasting of typhoon Jangmi (2008) near Taiwan Island
Authors: Wang Mingjun , Xue Ming , Zhao Kun 
Published: September 2016

AbstractThe impacts of radar data assimilation (DA) on the westward track deflection of Typhoon Jangmi (2008) near Taiwan Island and the deflection mechanism are investigated. Initial conditions from two data assimilation experiments with significant track forecast differences are analyzed and compared. The environmental, axisymmetric, wave number 1 to 3 asymmetric fields of the typhoon are decomposed by using vortex separation and Fourier decomposition methods. The components are selectively recomposed into new initial conditions that include different vortex‐scale components to examine the impact of individual components on the track prediction. The wave number 1 asymmetric structure is found to play a dominant role in the westward deflection of Typhoon Jangmi, and the accurate analysis of this component with radar DA helps to improve the track forecast. The wave number 1 asymmetric circulation is manifested as a pair of cyclonic and anticyclonic gyres with well‐defined ventilation flows through the inner‐core region, which provides additional steering of the typhoon vortex. The layer‐mean environmental steering flow and ventilation flow associated with the wave number 1 gyres are further calculated to quantitatively evaluate the impact of ventilation flow. The ventilation flow is shown to be responsible for most of the westward motion component, suggesting again its role in causing the westward track deflection of Typhoon Jangmi. The results also suggest the importance of analyzing vortex‐scale asymmetric structures for accurate tropical cyclone track forecasting, especially when there is a significant track deflection.
On physical limit of wireless digital transmission from radio wave propagation perspective
Authors: Karasawa Y. 
Published: September 2016

AbstractUnder a time‐invariant condition with thermal noise, the physical limit of digital transmission ability is governed by Shannon's channel capacity. However, in this formula, it does not contain factors on radio wave propagation environments. In other words, for the ultimate information transmission, a sufficiently long time for the coding and signal processing is expected. However, since wave propagation prevents its premise, there is another physical limit for digital transmission in a different perspective with Shannon's channel capacity. Even if the S/N ratio is sufficiently high, there is the limit for information transmission. This paper deals with this matter concerning physical limit of wireless transmission from a radio wave propagation viewpoint.
Fringe integral equations for the 2‐D wedges with soft and hard boundaries
Authors: Apaydin Gokhan , Sevgi Levent , Ufimtsev Pyotr Ya. 
Published: September 2016

AbstractNovel, fringe wave integral equations that account for the diffraction from nonpenetrable wedges with both soft and hard boundaries are derived. Method of moments simulation of fringe waves generated by a plane wave that excites the wedge is performed using this fringe wave integral equation. The results are compared with the exact physical theory of diffraction fringe waves.
The Henry problem: New semianalytical solution for velocity‐dependent dispersion
Authors: Fahs Marwan , Ataie‐Ashtiani Behzad , Younes Anis , Simmons Craig T. , Ackerer Philippe 
Published: September 2016

AbstractA new semianalytical solution is developed for the velocity‐dependent dispersion Henry problem using the Fourier‐Galerkin method (FG). The integral arising from the velocity‐dependent dispersion term is evaluated numerically using an accurate technique based on an adaptive scheme. Numerical integration and nonlinear dependence of the dispersion on the velocity render the semianalytical solution impractical. To alleviate this issue and to obtain the solution at affordable computational cost, a robust implementation for solving the nonlinear system arising from the FG method is developed. It allows for reducing the number of attempts of the iterative procedure and the computational cost by iteration. The accuracy of the semianalytical solution is assessed in terms of the truncation orders of the Fourier series. An appropriate algorithm based on the sensitivity of the solution to the number of Fourier modes is used to obtain the required truncation levels. The resulting Fourier series are used to analytically evaluate the position of the principal isochlors and metrics characterizing the saltwater wedge. They are also used to calculate longitudinal and transverse dispersive fluxes and to provide physical insight into the dispersion mechanisms within the mixing zone. The developed semianalytical solutions are compared against numerical solutions obtained using an in house code based on variant techniques for both space and time discretization. The comparison provides better confidence on the accuracy of both numerical and semianalytical results. It shows that the new solutions are highly sensitive to the approximation techniques used in the numerical code which highlights their benefits for code benchmarking.
Synthesis by In Situ‐Free Radical Polymerization, Characterization, and Properties of Poly (n‐butyl methacrylate)/Samarium‐Doped Titanium Dioxide Nanoparticles Composites
Authors: Suhailath K. , Jayakrishnan P. , Naufal B. , Periyat P. , Jasna V. C. , Ramesan M. T. 
Published: September 2016

AbstractUsing free radical polymerization process a series of samarium‐doped titanium dioxide (Sm3+‐doped TiO2) nanoparticles containing poly (n‐butyl methacrylate) (PBMA) composites were synthesized. The fabricated samples were characterized by XPS, FTIR, UV, XRD, DSC, TGA, flame retardancy studies, and impedance analyser. The shift in FTIR peak of the nanocomposites to higher wavenumber indicates the interfacial interaction between nanoparticles and PBMA. The UV spectra indicated that the metal oxide nanoparticles could enhances the interfacial interaction in the polymer composites. SEM images showed the uniform dispersion of nanoparticles into the macromolecular chain of PBMA. XRD patterns of the composites indicated the ordered arrangement of nanoparticles within the polymer and the regularity of the chain improved by the increase in concentration of nanoparticles. Better flame resistance and thermal stability were attained by the addition of nanoparticles. The flame retardancy and thermal stability of the composites were improved with the increase in concentration of Sm3+‐doped TiO2. The glass transition temperatures of the composites were much enhanced by the increase in weight percentage of nano‐filler. The AC conductivity, dielectric constant and dielectric loss tangent of the composites were higher than the pure PBMA and these properties enhanced with the loading of nanoparticles up to 7 wt.% and thereafter the values decreases.
Age estimation of immature human skeletal remains from the metaphyseal and epiphyseal widths of the long bones in the post‐natal period
Authors: Cardoso Hugo F. V. , Vandergugten John M. , Humphrey Louise T. 
Published: September 2016

AbstractObjectivesThis study provides regression and classical calibration models for the estimation of age from the dimensions of the metaphyses and epiphyses of the six long bones.MethodsA sample of 148 known sex and age individuals (56 females and 92 males), aged between birth and 12 years of age, selected from Portuguese and English skeletal collections. Age estimation models were obtained separately for each sex and for the sexes combined, for the entire sample and for the sample divided into two subsamples at the age of 2 years.ResultsThe best performing epiphysis is the proximal epiphysis of the tibia. For the metaphyses, the distal metaphysis of the tibia and the proximal metaphysis of the femur are best for individuals below and above 2 years of age, respectively. Growth of the metaphyses is similar to that of the diaphysis. Results suggest that age can be as accurately estimated from the width of the metaphyses and epiphyses as from the length of the diaphyses, or as from the length of the deciduous and permanent teeth.ConclusionsThese models may be useful for fragmentary material in both archaeological and forensic contexts. However, due to the background of the samples, the models would be most applicable to individuals exposed to adverse environmental conditions during growth and development. Metaphyseal and epiphyseal widths may be less affected by ecological conditions than diaphyseal length.
Direct Conversion from Terminal Borylene into Terminal Phosphinidene
Authors: Braunschweig Holger , Jimenez‐Halla J. Oscar C. , Radacki Krzysztof , Shang Rong 
Published: September 2016

AbstractThe first terminal manganese phosphinidene complex was quantitatively synthesized from a terminal alkylborylene complex. Its structure and bonding, as well as the reaction mechanism, were investigated through a combination of experimental and computational studies.
New bioactive Pt(II) binary and ternary metal complexes with guaifenesin drug: Synthesis, geometrical structure, and spectroscopic and thermal characterization
Authors: Mahmoud Walaa H. , Mohamed Gehad G. , Mahmoud Nessma F. 
Published: September 2016

Three new binary and ternary metal complexes of Pt(II) with guaifenesin (GFS) drug have been prepared by chelation to guaifenesin ligand (as primary ligand) and glycine amino acid (HGly) and 1,10‐phenanthroline (1,10‐Phen) (as secondary ligands). Characterization was conducted based on elemental analysis, molar conductance, infrared (IR) spectroscopy, thermogravimetric analysis and X‐ray diffraction. The complexes were found to have the formulae [Pt(GFS)2]⋅3H2O (1), [Pt(GFS)2(Gly)]Cl⋅H2O (2) and [Pt(GFS)2(Phen)]Cl2 (3). Magnetic and spectroscopic data revealed complexes 1–3 to have octahedral geometry. IR spectra suggested that GFS ligand coordinated in mononegative tridentate mode (OOO) for 1 but in neutral bidentate mode (OO) for 2 and 3. In addition, HGly behaves as mononegative bidentate coordinated to Pt(II) metal via deprotonated carboxylate O and amino group. IR data also evidenced the bidentate nature of 1,10‐Phen ligand. The molecular and electronic structure of Pt(II) complex 1 was optimized theoretically and the quantum chemical parameters were calculated. Complexes 1–3 were screened for their antibacterial activity on Gram‐positive bacteria (Bacillus subtilis and Staphylococcus aureus) and Gram‐negative bacteria (Escherichia coli and Neisseria gonorrhoeae) and for their in vitro antifungal activity against Candida albicans. The three Pt(II) complexes showed remarkable biological and cytotoxic activity. The chelates were also screened for their in vitro anticancer activity against the MFC7 breast cell line. Complex 3 showed the highest activity with a low IC50 value of 3.38 μg ml−1.
Cyclodextrin‐supported palladium complex: A highly active and recoverable catalyst for Suzuki–Miyaura cross‐coupling reaction in aqueous medium
Authors: Guo Yafei , Li Jiuling , Shi Xiwei , Liu Yang , Xie Kai , Liu Yuqi , Jiang Yubo , Yang Bo , Yang Rui 
Published: September 2016

A water‐soluble, cyclodextrin‐supported palladium complex (DACH‐Pd‐β‐CD) catalytic system was designed and synthesized, which can efficiently catalyze Suzuki–Miyaura cross‐coupling reactions between aryl halides and arylboronic acid in water under mild conditions. The catalyst was successfully characterized using the methods of transmission electron microscopy, energy‐dispersive X‐ray spectrometry, X‐ray diffraction, thermogravimetric analysis, and Fourier transform infrared and NMR spectroscopies. Furthermore, the catalyst can be easily separated from the reaction mixture and still maintain high catalytic activity after ten cycles. No leaching of palladium into the reaction solution occurred. The advantages of green solvent (water), short reaction times (2–6 h), low catalyst loading (0.001 mol%), excellent yields (up to 99%) and reusability of the catalyst mean it will have potential applications in green chemical synthesis.
Review of the bioanalytical methods for the determination of methotrexate and its metabolites in in vitro, preclinical and clinical studies: Case studies and perspectives
Authors: Patel Harilal , Giri Poonam , Ghoghari Ashok , Delvadia Prashant , Syed Muzeeb , Srinivas Nuggehally R. 
Published: September 2016

AbstractMethotrexate is an old drug that has found use in several therapeutic areas, such as cancer to treat various malignancies, rheumatoid arthtritis and inflammatory bowel disease. Owing to its structural properties of possessing two carboxylic acid groups and having low native fluorescence, it has provided technical challenges for development of bioanalytical methods. Also, in vivo metabolism leading to circulatory metabolites such as 7‐hydroxymethotrexate and 2,4‐diamino N10‐methylpteroic acid, as well as the formation of polyglutamate metabolites intracellularly have added further complexity for the assays in terms of the analytes that need to be quantified in addition to methotrexate. The present review is aimed at providing a concise tabular summary of chromatographic assays with respect to method nuances including assay/chromatographic conditions, key validation parameters and applicable remarks. Several case studies are reviewed under various subheadings to provide the challenges involved in the method development for methotrexate and metabolites. Finally, a discussion section is devoted to overall perspectives obtained from this review.
Good news and bad news
Authors: Hagler Donald J. 
Published: September 2016

Key Points:

Current delivery systems for the Sapien XT valve for the native pulmonary valve are unacceptable stiff and poorly design for implantation in the pulmonary outflow tract.
This report details improvisation of the Melody Ensemble for easier pulmonary outflow tract delivery of the Sapien XT valve.
The unacceptable cost of the utilization of two delivery systems for valve implantation, requires industry development of an safe, effective delivery system appropriate for the pulmonary outflow tract.
To neither bleed nor clot: That is the question
Authors: Davies Rhian E. , Gilchrist Ian C. 
Published: September 2016

Key Points

Patients with atrial fibrillation (AF) when stented with thin‐strut colbalt chrome stents may have a similar outcome to patients without AF.
Management of patients with AF potentially place patients at enhanced bleeding risk with triple antithrombotic therapy, or potential thrombotic risk if either oral anticoagulation is held or anti‐platelet therapy is truncated.
Guideline‐based oral anticoagulation for AF is expanding this patient group presenting to the cardiac catheterization laboratory, yet management decisions are still based on limited studies and rely on expert concensus.
Petlyuk Columns in Multicomponent Distillation Trains: Effect of Their Location on the Separation of Hydrocarbon Mixtures
Authors: Lucero‐Robles Evaristo , Gómez‐Castro Fernando Israel , Ramírez‐Márquez César , Segovia‐Hernández Juan Gabriel 
Published: September 2016

AbstractThermally coupled distillation columns (TCDC) are used to reduce energy requirements on the separation of liquid mixtures, which also reduces the environmental impact. The Petlyuk column is one of the TCDC with the highest reductions on heat duty. The use of distillation trains with Petlyuk columns is proposed to purify a multicomponent hydrocarbon mixture. Different sequences are studied, varying the location and number of Petlyuk columns to achieve separation of the components. Studied sequences are then optimized and compared in terms of energy requirements, environmental impact, and dynamic performance. The stream on which the component with the highest feed composition is separated has a great influence on the total heat duty and environmental impact. Nevertheless, the correlation between location and number of Petlyuk columns in the sequences and their control properties is low.