bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of chaotic advection on the timescales of cooling and crystallization of magma bodies at mid crustal levels
Authors: Petrelli Maurizio , El Omari Kamal , Le Guer Yves , Perugini Diego 
Published: January 2016

AbstractWe numerically define the thermochemical evolution of a subduction‐related crystal‐bearing magmatic mass at mid crustal levels (0.7 GPa, 20–25 km). Two main dynamic mechanisms are considered: (1) a pure buoyancy‐driven system where the convective flow is induced by density changes during magma cooling; (2) a buoyancy‐driven convective system governed by chaotic advection. The non‐Newtonian rheology of natural magmas is taken into account linking the Herschel‐Bulkley formulation with the results of fractional crystallization experiments of magmas with the same composition and at the same conditions of temperature and pressure of the studied system. The latent heat of crystallization is also considered in order to address the thermal release in the system induced by the crystallization. Results indicate that the development of chaotic advection generates a complex thermochemical evolution of the system speeding up the crystallization process and the timing required to reach the jamming condition relative to the pure buoyancy‐driven convective system (nearly 2 times faster). Our results have important implications for both the rheological history of the magmatic body and the refilling of shallower magmatic systems. In particular, (1) a time‐dependent composition ranging from basalt to andesite can be extracted from an initial basaltic magmatic batch; (2) at the attainment of the maximum packing fraction (i.e., just before the jamming condition), homogeneous andesitic melts can be potentially extracted from the system; and (3) the development of chaotic advection within the system allows for the extraction of andesitic melt in shorter times compared to a buoyancy‐dominated system.
Crustal anisotropy beneath Pacific Ocean‐Islands from harmonic decomposition of receiver functions
Authors: Olugboji Tolulope Morayo , Park Jeffrey 
Published: January 2016

AbstractCrustal anisotropy beneath ocean islands can be attributed to preferentially aligned minerals, cracks, or dike structures. Stacked with harmonic weighting, receiver functions from permanent ocean‐island stations display evidence of strong and distinct anisotropy parameters in the underlying crust and underplated layer. We analyze data for 11 IRIS‐GSN stations in the Pacific Ocean. We observe the prevalence of two‐lobed receiver function (RF) amplitude variations with back‐azimuth, consistent with “slow” tilted‐axis anisotropy. In most cases the anisotropy is accommodated in the underplated crust. Synthetic modeling of a representative station indicates that the strength of anisotropy of Vp=10% and Vs=5% is possible. The strike direction of the inferred symmetry axis tends to align with plate motion, with some scatter. At stations in the northwest Pacific i.e., KWAJ, TARA, and WAKE, the strike direction of the symmetry axis aligns with plate motion at the time of volcano emplacement. Beneath station POHA and the closest stations to the present‐day Hawaiian hotspot, alignment of the symmetry axis is almost orthogonal to the plate motion. We attribute the crustal anisotropy to the preferred alignment of dike structures that transported asthenospheric magma toward the seafloor volcanic edifice. Our results suggest that the thermal‐plume origin for ocean islands must be supplemented by tectonic‐stress heterogeneities that allow magma to penetrate the lithosphere via fractures. Magma‐transport fractures should align normal to the least‐compressive direction, which are predicted by theoretical models to align approximately with plate motion at the time of emplacement.
Satellite‐based empirical models linking river plume dynamics with hypoxic area and volume
Authors: Le Chengfeng , Lehrter John C. , Hu Chuanmin , Obenour Daniel R. 
Published: January 2016

AbstractSatellite‐based empirical models explaining hypoxic area and volume variation were developed for the seasonally hypoxic (O2 < 2 mg L−1) northern Gulf of Mexico adjacent to the Mississippi River. Annual variations in midsummer hypoxic area and volume were related to Moderate Resolution Imaging Spectroradiometer‐derived monthly estimates of river plume area (km2) and average, inner shelf chlorophyll a concentration (Chl a, mg m−3). River plume area in June was negatively related with midsummer hypoxic area (km2) and volume (km3), while July inner shelf Chl a was positively related to hypoxic area and volume. Multiple regression models using river plume area and Chl a as independent variables accounted for most of the variability in hypoxic area (R2 = 0.92) or volume (R2 = 0.89). These models explain more variation in hypoxic area than models using Mississippi River nutrient loads as independent variables. The results here also support a hypothesis that confinement of the river plume to the inner shelf is an important mechanism controlling hypoxia area and volume in this region.
Density duct formation in the wake of a travelling ionospheric disturbance: Murchison Widefield Array observations
Authors: Loi Shyeh Tjing , Cairns Iver H. , Murphy Tara , Erickson Philip J. , Bell Martin E. , Rowlinson Antonia , Arora Balwinder Singh , Morgan John , Ekers Ronald D. , Hurley‐Walker Natasha , Kaplan David L. 
Published: January 2016

AbstractGeomagnetically aligned density structures with a range of sizes exist in the near‐Earth plasma environment, including 10–100 km wide VLF/HF wave‐ducting structures. Their small diameters and modest density enhancements make them difficult to observe, and there is limited evidence for any of the several formation mechanisms proposed to date. We present a case study of an event on 26 August 2014 where a travelling ionospheric disturbance (TID) shortly precedes the formation of a complex collection of field‐aligned ducts, using data obtained by the Murchison Widefield Array (MWA) radio telescope. Their spatiotemporal proximity leads us to suggest a causal interpretation. Geomagnetic conditions were quiet at the time, and no obvious triggers were noted. Growth of the structures proceeds rapidly, within 0.5 h of the passage of the TID, attaining their peak prominence 1–2 h later and persisting for several more hours until observations ended at local dawn. Analyses of the next 2 days show field‐aligned structures to be preferentially detectable under quiet rather than active geomagnetic conditions. We used a raster scanning strategy facilitated by the speed of electronic beamforming to expand the quasi‐instantaneous field of view of the MWA by a factor of 3. These observations represent the broadest angular coverage of the ionosphere by a radio telescope to date.
A minimal probabilistic model for soil moisture in seasonally dry climates
Authors: Dralle David N. , Thompson Sally E. 
Published: January 2016

AbstractIn seasonally dry climates, a distinct rainy season is followed by a pronounced dry season during which rainfall often makes a negligible contribution to soil moisture. Using stochastic analytical models of soil moisture to represent the effects of this seasonal change has been hindered by the need to mathematically represent the stochastic influence of wet season climate on dry season soil water dynamics. This study presents a simple process‐based stochastic model for soil moisture dynamics, which explicitly models interseasonal transient dynamics while accounting for carry over soil moisture storage between the wet and dry seasons, and allows a derivation of an analytical expression for the dry season mean first passage time below a soil moisture threshold. Such crossing times pose controls on both vegetation productivity and water stress during dry summers. The new model, along with an existing model that incorporates nonzero dry season rainfall but not variability in the soil moisture condition at the start of the dry season, are tested against data from the Tonzi Ranch Ameriflux site. Both models predict first passage times well for high soil moisture thresholds, but the new model improves prediction at lower thresholds. The annual soil moisture probability distribution function (PDF) from the new model also compares well with observations.
Continuous higher order sliding mode control with adaptation of air breathing hypersonic missile
Authors: Yu Polk , Shtessel Yuri , Edwards Christopher 
Published: January 2016

SummaryHypersonic missile control in the terminal phase is addressed using continuous adaptive higher order sliding mode (AHOSM) control with adaptation. The AHOSM self‐tuning controller is proposed and studied. The double‐layer adaptive algorithm is based on equivalent control concepts and ensures non‐overestimation of the control gain to help mitigating control chattering. The proposed continuous AHOSM control is validated via simulations of a hypersonic missile in the terminal phase. The robustness and high‐accuracy output tracking in the presence of matched and unmatched external disturbances and missile model uncertainties is demonstrated. Copyright © 2016 John Wiley & Sons, Ltd.
Fabrication and structural tuning of novel composite hollow fiber membranes for pervaporation
Authors: Zhu Jia Ming , Li Ge , Jiang Lan Ying 
Published: January 2016

ABSTRACTA series of polysiloxaneimide (PSI)/polyetherimide (PEI) composite hollow fibers were fabricated by coextrusion and phase inversion. The hydrophobic PSI outer layer was set as the selective layer which was supported by the PEI inner layer. The PSI was synthesized by polycondensation of 3,3′,4,4′‐Biphenyltetracarboxylic Dianhydride (BPDA) with amino siloxane X‐22‐161A and a chain extender, 1,3‐Bis (3‐aminopropyl) −1,1,3,3‐tertramethyldisiloxane (BATS). It was found that the macroscopic uniformity of PSI layer was dependent on the dope formulation, coagulant composition and dope flow rate: (1) the higher similarity degree of the solvent(s) for different layers in terms of solubility parameters, (2) the utilization of surfactant as a component in the water coagulant, and (3) higher flow rates of the outer layer dopes, led to the formation of more uniform and smoother PSI outer layer. The maximum outer layer thickness was around 2 μm. The bulk of the PEI layers were porous with finger like macrovoids. The outer surface of the inner PEI layer for some batches of the hollow fibers was confirmed to be porous. The original dual‐layer hollow fibers showed poor pervaporation performance. Post treatment was applied to cure the hollow fiber, delivering composite membranes with performance dominated by the coating material of PDMS. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43324.
Composite Titanium Silicon Carbide as a Promising Catalyst Support for High‐Temperature Proton‐Exchange Membrane Fuel Cell Electrodes
Authors: Lobato Justo , Zamora Hector , Plaza Jorge , Rodrigo Manuel A. 
Published: January 2016

AbstractThis manuscript focuses on the assessment of a composite titanium silicon carbide (SiCTiC) as a catalyst support for high‐temperature proton‐exchange membrane fuel cells (HT‐PEMFCs). The support showed very high thermal and electrochemical resistances under harsh conditions (phosphoric acid). Pt nanoparticles were successfully deposited on the new SiCTiC support and it demonstrated a higher stability (lower agglomeration of the nanoparticles) than the more conventional Vulcan carbon‐based catalyst, both in a commercial formulation and as prepared in the lab, with the same procedure as that used for the novel carbide material under very harsh conditions.
Organoselenium‐Catalyzed Oxidative Ring Expansion of Methylenecyclopropanes with Hydrogen Peroxide
Authors: Yu Lei , Chen Fenglin , Ding Yuanhua 
Published: January 2016

AbstractCatalyst screening and optimization of reaction conditions allowed control of the organoselenium‐catalyzed oxidative ring expansion of highly active methylenecyclopropanes to give substituted cyclobutanones selectively. This protocol employs H2O2 as a clean oxidant and generates no waste and, therefore, provides green access to useful, but not readily available, substituted cyclobutanones under mild conditions.
Alkyl Substitution Effect on Oxidation Stability of Sulfone‐Based Electrolytes
Authors: Su Chi‐Cheung , He Meinan , Redfern Paul , Curtiss Larry A. , Liao Chen , Zhang Lu , Burrell Anthony K. , Zhang Zhengcheng 
Published: January 2016

AbstractOrganic sulfone compounds have been widely used as high‐voltage electrolytes for lithium‐ion batteries for decades. However, owing to the complexity of the synthesis of new sulfones, only a few commercially available sulfones have been studied. In this paper, we report the synthesis of new sulfone compounds with various substituent groups and the impact of the substituent group on the oxidation stability of sulfones. Electrochemical floating tests using a 5 V LiNi0.5Mn1.5O4 spinel cathode and density functional theory calculations showed that the cyclopentyl‐substituted sulfone McPS suffered from oxidation instability, starting from 4.9 V versus Li+/Li, as observed by the large leakage currents. On the other hand, the isopropyl‐substituted sulfone MiPS and tetramethylene substituted sulfone TMS showed much improved oxidation stability under identical testing conditions. The substitution structure of the sulfone plays a significant role in the determination of its oxidative stability and should first be considered for the development of new sulfone‐based electrolytes for high‐voltage, high‐energy lithium‐ion batteries.
Recent Advances in the Synthesis of Indanes and Indenes
Authors: Gabriele Bartolo , Mancuso Raffaella , Veltri Lucia 
Published: January 2016

AbstractIndanes and indenes are among the most important carbocycles. Many indane and indene derivatives have shown important pharmacological activities, and the indane and indene nuclei are structural motifs present in several natural products of biological relevance. In spite of their importance, only a few reviews on their preparation methods have appeared so far in the literature, the most recent ones being published about ten years ago. The present Review is aimed at filling this gap, presenting some of the most important and innovative approaches to indanes and indenes that have been published in the course of the last ten years (coverage: from 2005 to May, 2015).
Extending the Row of Lanthanide Tetrafluorides: A Combined Matrix‐Isolation and Quantum‐Chemical Study
Authors: Vent‐Schmidt Thomas , Fang Zongtang , Lee Zachary , Dixon David , Riedel Sebastian 
Published: January 2016

AbstractOnly the neutral tetrafluorides of Ce, Pr, and Tb as well as the [LnF7]3− anions of Dy and Nd, with the metal in the +IV oxidation state, have been previously reported. We report our attempts to extend the row of neutral lanthanide tetrafluorides through the reaction of laser‐ablated metal atoms with fluorine and their stabilization and characterization by matrix‐isolation IR spectroscopy. In addition to the above three tetrafluorides, we found two new tetrafluorides, 3NdF4 and 7DyF4, both of which are in the +IV oxidation state, which extends this lanthanide oxidation state to two new metals. Our experimental results are supported by quantum‐chemical calculations and the role of the lanthanide oxidation state is discussed for both the LnF4 and [LnF4]− species. Most of the LnF4 species are predicted to be in the +IV oxidation state and all of the [LnF4]− anions are predicted to be in the +III oxidation state. The LnF4 species are predicted to be strong oxidizing agents and the LnF3 species are predicted to be moderate to strong Lewis acids.
An Iron(III) Catalyst with Unusually Broad Substrate Scope in Regioselective Alkylation of Diols and Polyols
Authors: Ren Bo , Ramström Olof , Zhang Qiang , Ge Jiantao , Dong Hai 
Published: January 2016

AbstractIn this study, [Fe(dibm)3] (dibm=diisobutyrylmethane) is shown to have unusually broad scope as a catalyst for the selective monoalkylation of a diverse set of 1,2‐ and 1,3‐diol‐containing structures. The mechanism is proposed to proceed via a cyclic dioxolane‐type intermediate, formed between the iron(III) species and two adjacent hydroxyl groups. This approach represents the first transition‐metal catalysts that are able to replace stoichiometric amounts of organotin reagents in regioselective alkylation. The reactions generally lead to very high regioselectivities and high yields, on par with, or better than, previous methods used for regioselective alkylation.
Generation of an N→B Ladder‐type Structure by Regioselective Hydroboration of an Alkenyl‐Functionalized Quaterpyridine
Authors: Grandl Markus , Sun Yu , Pammer Frank 
Published: January 2016

AbstractAn unusual reactivity of 2‐(1‐alkenyl)‐pyridines towards hydroboration with 9H‐borabicyclo[3.3.1]nonane (9H‐BBN) has been employed to selectively introduce two borane groups into a conjugated quaterpyridine. Quantitative conversion of the substrate was observed with exclusive regioselectivity. A molecular structure that allows intramolecular N→B coordination was generated. The effect of the ladder formation on the molecular structure and the electronic properties of the conjugated system have been investigated. The synthetic strategy demonstrated herein offers a facile access to N→B ladder‐type structures from readily available substrates, and allows to simultaneously introduce several boron centers under mild conditions.
Risk factors for cardiovascular disease and mortality events in adults with type 2 diabetes — a 10‐year follow‐up: Tehran Lipid and Glucose Study
Authors: Afsharian Sheila , Akbarpour Samaneh , Abdi Hengameh , Sheikholeslami Farhad , Moeini Ali Siamak , Khalili Davood , Momenan Amir Abbas , Azizi Fereidoun , Hadaegh Farzad 
Published: January 2016

AbstractBackgroundTo identify risk factors for cardiovascular disease (CVD) and mortality events in patients with type 2 diabetes and to calculate their population attributable fraction among a representative Iranian population.MethodsA total of 1198 patients with type 2 diabetes (504 men and 694 women), aged ≥30 years, without prevalent CVD, with a median follow‐up of 10 years were included in current study. To examine the association between risk factors and their outcomes, multivariate sex‐adjusted Cox proportional hazard regression models were used.ResultsDuring the study, 281 and 172 participants experienced CVD and all‐cause mortality events, respectively. Regarding CVD events, fasting plasma glucose (FPG) level of 7.22–<10 mmol/L [hazard ratio (HR): 1.46, 95% CI 1.12–1.96], FPG level ≥10 mmol/L (HR 2.04, 1.53–2.72), hypertension (HR 1.65, 1.28–2.13), hypercholesterolaemia (HR 1.96, 1.40–2.75) and high waist to hip ratio (HR 1.30, 0.99–1.70; p = 0.051) were significant predictors, and corresponding population attributable fractions were 9.76, 17.84, 23.26, 41.63 and 14.76%, respectively. Considering all‐cause mortality events, hypertension (HR 1.70, 1.23–2.36), FPG level ≥10 mmol/L (HR 2.31, 1.55–3.20) and smoking (HR 1.45, 1.03–2.04) were significant predictors, and corresponding population attributable fractions were 25.81, 20.88 and 11.18%, respectively. Meanwhile, being overweight or obese was associated with lower all‐cause and CVD mortality events.ConclusionsAmong modifiable risk factors in patients with type 2 diabetes, hypercholesterolaemia and central adiposity for CVD, smoking for mortality events and hypertension and poor glycaemic control for both outcomes need to be paid most attention by healthcare professionals. Copyright © 2016 John Wiley & Sons, Ltd.
Dominant male song performance reflects current immune state in a cooperatively breeding songbird
Authors: York Jenny E. , Radford Andrew N. , Groothuis Ton G. , Young Andrew J. 
Published: January 2016

AbstractConspicuous displays are thought to have evolved as signals of individual “quality”, though precisely what they encode remains a focus of debate. While high quality signals may be produced by high quality individuals due to “good genes” or favourable early‐life conditions, whether current immune state also impacts signalling performance remains poorly understood, particularly in social species. Here, we experimentally demonstrate that male song performance is impaired by immune system activation in the cooperatively breeding white‐browed sparrow weaver (Plocepasser mahali). We experimentally activated the immune system of free‐living dominant males via subcutaneous injection of phytohemagglutinin (PHA) and contrasted its effects with those of a control (phosphate buffered saline) injection. PHA‐challenged males showed significant reductions in both the duration and the rate of their song performance, relative to controls, and this could not be readily attributed to effects of the challenge on body mass, as no such effects were detected. Furthermore, male song performance prior to immune‐challenge predicted the scale of the inflammatory response to the challenge. Our findings suggest that song performance characteristics are impacted by current immune state. This link between current state and signal performance might therefore contribute to enforcing the honesty of signal performance characteristics. Impacts of current state on signaling may be of particular importance in social species, where subordinates may benefit from an ability to identify and subsequently challenge same‐sex dominants in a weakened state.
Bifidobacterially produced, C18:3 and C18:4 conjugated fatty acids exhibit in vitro anti‐carcinogenic and anti‐microbial activity
Authors: Hennessy Alan A. , Ross Paul , Devery Rosaleen , Stanton Catherine 
Published: January 2016

Conjugated fatty acid (CFA)s have shown a range of in vitro and in vivo bioactivities prompting increased endeavours both to identify novel sources and to characterize their properties. Strains of bifidobacteria possess the capacity to produce a range of CFAs including conjugated α‐linolenic acid (CLNA), conjugated γ‐linolenic acid (CGLA), and conjugated stearidonic acid (CSA), and in the current study these CFA were assessed for anti‐proliferative activity using the SW480 colon cancer cell line. Additionally, these fatty acids were also assessed for inhibitory activity against select gastro‐intestinal pathogens and potential probiotic CFA producers. The results demonstrated that the CFA displayed greater inhibitory activity against the SW480 cells than a normal fetal human colonic cell line (FHC), suggesting selective anti‐proliferative potential in vitro. Studies into the mechanism behind this inhibitory activity indicated potential roles for increased cellular lipid peroxidation, altered cellular phospholipid composition, and reductions in the cellular content of Bcl‐2. Microbiological studies also demonstrated that the CFA displayed inhibitory activity against selected pathogens, while CFA producing bifodobacteria remained unaffected. CFAs were particularly effective in the inhibition of the methicillin resistant strain Staphylococcus aureus ATCC 43300.Practical applications: We have demonstrated that bifidobacterially produced C18:3 and C18:4 CFAs may have potential in the control of colon cancer. Additionally, their inhibitory properties against common gastrointestinal pathogens (particularly the methicillin resistant strain S. aureus ATCC 43300) and not potential probiotic CFA producing bifidobacteria may indicate further therapeutic potential or a metabolic process that gives CFA producing microbes a competitive advantage in the complex environment that is the gastrointestinal tract.Strains of bifidobacteria such as Bifidobacterium breve DPC 6330 possess the capacity to bioconvert α‐linolenic, γ‐linolenic, and stearidonic acids to their conjugated derivatives under fermentative conditions. In vitro bioassays have indicated that these conjugated derivatives possess anti‐microbial activity, particularly against microbial pathogens including Staphyloccus aureus, and anti‐carcinogenic properties against colonic cancer cell lines such as SW480.