bluuebunny/crossref_metadata_2025_split huggingface dataset:
Automatic scaling of HF swept‐frequency backscatter ionograms
Authors: Song Huan , Hu Yaogai , Jiang Chunhua , Zhou Chen , Zhao Zhengyu 
Published: April 2015

AbstractThis paper describes a method for automatically scaling HF swept‐frequency backscatter ionograms, which can be applied to a low‐power oblique backscatter sounding system. Based on the information of vertical echo in the ionogram, propagation mode is recognized from the amplitude differences betweenElayer andFlayer echoes. Points on the leading edge are extracted by using minimum group path delay theory. The spurious points are removed by using residual analysis. A multiple linear polynomial was adopted to fit the extracted leading edge points. Smooth fitting curves can then be obtained. Automatic scaling results from 362 ionograms show that the proposed method can efficiently recognize propagation modes and extract leading edge curves by taking full advantages of echo characteristics and echo amplitudes in the ionograms. This novel method can be applied into real‐time backscatter ionogram scaling, which facilitates the extensive usage of oblique backscatter soundings.
Delta channel networks: 1. A graph‐theoretic approach for studying connectivity and steady state transport on deltaic surfaces
Authors: Tejedor Alejandro , Longjas Anthony , Zaliapin Ilya , Foufoula‐Georgiou Efi 
Published: April 2015

AbstractRiver deltas are intricate landscapes with complex channel networks that self‐organize to deliver water, sediment, and nutrients from the apex to the delta top and eventually to the coastal zone. The natural balance of material and energy fluxes, which maintains a stable hydrologic, geomorphologic, and ecological state of a river delta, is often disrupted by external perturbations causing topological and dynamical changes in the delta structure and function. A formal quantitative framework for studying delta channel network connectivity and transport dynamics and their response to change is lacking. Here we present such a framework based on spectral graph theory and demonstrate its value in computing delta's steady state fluxes and identifying upstream (contributing) and downstream (nourishment) areas and fluxes from any point in the network. We use this framework to construct vulnerability maps that quantify the relative change of sediment and water delivery to the shoreline outlets in response to possible perturbations in hundreds of upstream links. The framework is applied to the Wax Lake delta in the Louisiana coast of the U.S. and the Niger delta in West Africa. In a companion paper, we present a comprehensive suite of metrics that quantify topologic and dynamic complexity of delta channel networks and, via application to seven deltas in diverse environments, demonstrate their potential to reveal delta morphodynamics and relate to notions of vulnerability and robustness.
Provenance of plumes in global convection models
Authors: Hassan Rakib , Flament Nicolas , Gurnis Michael , Bower Dan J. , Müller Dietmar 
Published: April 2015

AbstractIn global convection models constrained by plume motions and subduction history over the last 230 Myr, plumes emerge preferentially from the edges of thermochemical structures that resemble present‐day large low shear velocity provinces (LLSVPs) beneath Africa and the Pacific Ocean. It has been argued that large igneous provinces (LIPs) erupting since 200 Ma may originate from plumes that emerged from the edges of the LLSVPs and numerical models have been devised to validate this hypothesis. Although qualitative assessments that are broadly in agreement with this hypothesis have been derived from numerical models, a quantitative assessment has been lacking. We present a novel plume detection scheme and derive Monte Carlo‐based statistical correlations of model plume eruption sites and reconstructed LIP eruption sites. We show that models with a chemically anomalous lower mantle are highly correlated to reconstructed LIP eruption sites, whereas the confidence level obtained for a model with purely thermal plumes falls just short of 95%. A network of embayments separated by steep ridges form in the deep lower mantle in models with a chemically anomalous lower mantle. Plumes become anchored to the peaks of the chemical ridges and the network of ridges acts as a floating anchor, adjusting to slab push forces through time. The network of ridges imposes a characteristic separation between conduits that can extend into the interior of the thermochemical structures. This may explain the observed clustering of reconstructed LIP eruption sites that mostly but not exclusively occur around the present‐day LLSVPs.
On the temporal evolution of long‐wavelength mantle structure of the Earth since the early Paleozoic
Authors: Zhong Shijie , Rudolph Maxwell L. 
Published: April 2015

AbstractThe seismic structure of the Earth's lower mantle is characterized by a dominantly degree‐2 pattern with the African and Pacific large low shear velocity provinces (i.e., LLSVP) that are separated by circum‐Pacific seismically fast anomalies. It is important to understand the origin of such a degree‐2 mantle structure and its temporal evolution. In this study, we investigated the effects of plate motion history and mantle viscosity on the temporal evolution of the lower mantle structure since the early Paleozoic by formulating 3‐D spherical shell models of thermochemical convection. For convection models with realistic mantle viscosity and no initial structure, it takes about ∼50 Myr to develop dominantly degree‐2 lower mantle structure using the published plate motion models for the last either 120 Ma or 250 Ma. However, it takes longer time to develop the mantle structure for more viscous mantle. While the circum‐Pangea subduction in plate motion history models promotes the formation of degree‐2 mantle structure, the published pre‐Pangea plate motions before 330 Ma produce relatively cold lower mantle in the African hemisphere and significant degree‐1 structure in the early Pangea (∼300 Ma) or later times, even if the lower mantle has an initially degree‐2 structure and a viscosity as high as 1023 Pas. This suggests that the African LLSVP may not be stationary since the early Paleozoic. With the published plate motion models and lower mantle viscosity of 1022 Pas, our mantle convection models suggest that the present‐day degree‐2 mantle structure may have largely been formed by ∼200 Ma.
What drives seasonal change in oligotrophic area in the subtropical North Atlantic?
Authors: Dave Apurva C. , Barton Andrew D. , Lozier M. Susan , McKinley Galen A. 
Published: April 2015

AbstractThe oligotrophic regions of the subtropical gyres cover a significant portion of the global ocean, and exhibit considerable but poorly understood intraseasonal, interannual, and longer‐term variations in spatial extent. Here using historical observations of surface ocean nitrate, wind, and currents, we have investigated how horizontal and vertical supplies of nitrate control seasonal changes in the size and shape of oligotrophic regions of the subtropical North Atlantic. In general, the oligotrophic region of the subtropical North Atlantic is associated with the region of weak vertical supply of nitrate. Though the total vertical supply of nitrate here is generally greater than the total horizontal supply, we find that seasonal expansion and contraction of the oligotrophic region is consistent with changes in horizontal supply of nitrate. In this dynamic periphery of the subtropical gyre, the seasonal variations in chlorophyll are linked to variations in horizontal nitrate supply that facilitate changes in intracellular pigment concentrations, and to a lesser extent, phytoplankton biomass. Our results suggest that horizontal transports of nutrient are crucial in setting seasonal cycles of chlorophyll in large expanses of the subtropical North Atlantic, and may play a key and underappreciated role in regulating interannual variations in these globally important marine ecosystems.
Influence of preonset land atmospheric conditions on the Indian summer monsoon rainfall variability
Authors: Rai Archana , Saha Subodh K. , Pokhrel Samir , Sujith K. , Halder Subhadeep 
Published: April 2015

AbstractA possible link between preonset land atmospheric conditions and the Indian summer monsoon rainfall (ISMR) is explored. It is shown that, the preonset positive (negative) rainfall anomaly over northwest India, Pakistan, Afghanistan, and Iran is associated with decrease (increase) in ISMR, primarily in the months of June and July, which in turn affects the seasonal mean. ISMR in the months of June and July is also strongly linked with the preonset 2 m air temperature over the same regions. The preonset rainfall/2 m air temperature variability is linked with stationary Rossby wave response, which is clearly evident in the wave activity flux diagnostics. As the predictability of Indian summer monsoon relies mainly on the El Niño–Southern Oscillation (ENSO), the found link may further enhance our ability to predict the monsoon, particularly during a non‐ENSO year.
On the probabilistic structure of water age
Authors: Porporato Amilcare , Calabrese Salvatore 
Published: April 2015

AbstractThe age distribution of water in hydrologic systems has received renewed interest recently, especially in relation to watershed response to rainfall inputs. The purpose of this contribution is first to draw attention to existing theories of age distributions in population dynamics, fluid mechanics and stochastic groundwater, and in particular to the McKendrick‐von Foerster equation and its generalizations and solutions. A second and more important goal is to clarify that, when hydrologic fluxes are modeled by means of time‐varying stochastic processes, the age distributions must themselves be treated as random functions. Once their probabilistic structure is obtained, it can be used to characterize the variability of age distributions in real systems and thus help quantify the inherent uncertainty in the field determination of water age. We illustrate these concepts with reference to a stochastic storage model, which has been used as a minimalist model of soil moisture and streamflow dynamics.
Biologic monitoring and surveillance results for the department of veterans affairs' depleted uranium cohort: Lessons learned from sustained exposure over two decades
Authors: McDiarmid Melissa A. , Gaitens Joanna M. , Hines Stella , Condon Marian , Roth Tracy , Oliver Marc , Gucer Patricia , Brown Lawrence , Centeno Jose A. , Streeten Elizabeth , Squibb Katherine S. 
Published: April 2015

BackgroundA small group of Gulf War I veterans wounded in depleted uranium (DU) friendly fire incidents have been monitored in a clinical surveillance program at the Veterans Affairs Medical Center, Baltimore since 1994.MethodsAn in‐patient clinical surveillance protocol was performed on 35 members of the cohort, including exposure monitoring for total and isotopic uranium concentrations in urine and a comprehensive assessment of health outcomes.ResultsAlthough urine U concentrations continue to be elevated in this group, illustrating on‐going in situ mobilization of U from embedded fragments, no consistent U‐related health effects have been observed.ConclusionsNow more than 20 years since first exposure to DU, an aging cohort of military veterans continues to show no U‐related health effects in known target organs of U toxicity. As tissue concentrations continue to accrue with exposure duration, critical tissue‐specific U concentration thresholds may be reached, thus recommending on‐going surveillance of this veteran cohort. Am. J. Ind. Med. 58:583–594, 2015. © 2015 Wiley Periodicals, Inc.
Expression of heme oxygenase‐1 in eosinophilic and non‐eosinophilic chronic rhinosinusitis with nasal polyps: modulation by cytokines
Authors: Yu Zhijian , Wang Yu , Zhang Jia , Li Lei , Wu Xingmei , Ma Renqiang , Han Miaomiao , Xu Geng , Wen Weiping , Li Huabin 
Published: April 2015

BackgroundOxidative stress is characteristic of chronic airway inflammatory diseases such as asthma, chronic obstructive pulmonary disease and chronic rhinosinusitis with nasal polyps (CRSwNP). Heme oxygenase (HO)‐1 has been proposed to be a cytoprotective enzyme against oxidative stress in CRSwNP. However, the expression and regulation of HO‐1 in eosinophilic CRSwNP (ECRS) and non‐eosinophilic CRSwNP (non‐ECRS) subsets has not been well documented.MethodsNasal polyps and uncinate process tissues were enrolled from 40 CRSwNP patients (ECRS, 17; non‐ECRS, 23) and 20 control subjects, respectively. The messenger RNA (mRNA) and protein expression of HO‐1 was examined using qRT‐PCR, immunohistochemistry, and Western blot staining. Moreover, the stimulatory effects of several cytokines (interferon γ [IFN‐γ], interleukin [IL]‐5, and IL‐13, etc.) on HO‐1 mRNA expression in cultured nasal explants were evaluated.ResultsThe mRNA and protein expression of HO‐1 was significantly increased in polyp tissues compared with healthy controls (p < 0.05), and the non‐ECRS subset showed significantly increased HO‐1 expression compared with the ECRS subset (p < 0.05). Moreover, in cultured nasal explant, HO‐1 mRNA was significantly upregulated in the presence of IFN‐γ, IL‐27, IL‐5, IL‐13, and IL‐17A, but was significantly inhibited by transforming growth factor β1 (TGF‐β1) (p < 0.05).ConclusionOur findings indicate that HO‐1 was differentially expressed and regulated in ECRS and non‐ECRS patients.
Synthesis and flammability testing of epoxy functionalized phosphorous‐based flame retardants
Authors: Benin Vladimir , Cui Xuemei , Morgan Alexander B. , Seiwert Karl 
Published: April 2015

ABSTRACTSeveral potential new phosphorus‐containing flame retardant molecules were evaluated for heat release reduction potential by incorporation of the molecules into a polyurethane, generated from methylene diphenyl diisocyanate and 1,3‐propane diol. The heat release reduction potential of these substances was evaluated using the pyrolysis combustion flow calorimeter (PCFC). The polyurethanes were prepared in the presence of the potential flame retardants via solvent mixing and copolymerization methods to qualitatively evaluate their potential reactivity into the polyurethane prior to heat release testing. The functionality of the flame retardants was epoxide based that would potentially react with the diol during polyurethane synthesis. Flammability testing via PCFC showed that the heat release reduction potential of each of the flame retardants was structure dependent, with phosphates tending to show more effectiveness than phosphonates in this study, and alkyl functionalized phosphorus groups (phosphate or phosphonate) being more effective at heat release reduction than cyclic functionalized groups. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42296.
A Role for Gut Microbiota and the Metabolite‐Sensing Receptor GPR43 in a Murine Model of Gout
Authors: Vieira Angélica T. , Macia Laurence , Galvão Izabela , Martins Flaviano S. , Canesso Maria Cecília C. , Amaral Flávio A. , Garcia Cristiana C. , Maslowski Kendle M. , De Leon Ellen , Shim Doris , Nicoli Jacques R. , Harper Jacquie L. , Teixeira Mauro M. , Mackay Charles R. 
Published: April 2015

ObjectiveHost–microbial interactions are central in health and disease. Monosodium urate monohydrate (MSU) crystals cause gout by activating the NLRP3 inflammasome, leading to interleukin‐1β (IL‐1β) production and neutrophil recruitment. This study was undertaken to investigate the relevance of gut microbiota, acetate, and the metabolite‐sensing receptor GPR43 in regulating inflammation in a murine model of gout.MethodsGout was induced by the injection of MSU crystals into the knee joints of mice. Macrophages from the various animals were stimulated to determine inflammasome activation and production of reactive oxygen species (ROS).ResultsInjection of MSU crystals caused joint inflammation, as seen by neutrophil influx, hypernociception, and production of IL‐1β and CXCL1. These parameters were greatly decreased in germ‐free mice, mice treated with antibiotics, and GPR‐43–deficient mice. Recolonization or administration of acetate to germ‐free mice restored inflammation in response to injection of MSU crystals. In vitro, macrophages produced ROS and assembled the inflammasome when stimulated with MSU. Macrophages from germ‐free animals produced little ROS, and there was little inflammasome assembly. Similar results were observed in macrophages from GPR‐43–deficient mice. Treatment of germ‐free mice with acetate restored in vitro responsiveness of macrophages to MSU crystals.ConclusionIn the absence of microbiota, there is decreased production of short‐chain fatty acids that are necessary for adequate inflammasome assembly and IL‐1β production in a manner that is at least partially dependent on GPR43. These results clearly show that the commensal microbiota shapes the host's ability to respond to an inflammasome‐dependent acute inflammatory stimulus outside the gut.
Adaptation to high throughput batch chromatography enhances multivariate screening
Authors: Barker Gregory A. , Calzada Joseph , Herzer Sibylle , Rieble Siegfried 
Published: April 2015

AbstractHigh throughput process development offers unique approaches to explore complex process design spaces with relatively low material consumption. Batch chromatography is one technique that can be used to screen chromatographic conditions in a 96‐well plate. Typical batch chromatography workflows examine variations in buffer conditions or comparison of multiple resins in a given process, as opposed to the assessment of protein loading conditions in combination with other factors. A modification to the batch chromatography paradigm is described here where experimental planning, programming, and a staggered loading approach increase the multivariate space that can be explored with a liquid handling system. The iterative batch chromatography (IBC) approach is described, which treats every well in a 96‐well plate as an individual experiment, wherein protein loading conditions can be varied alongside other factors such as wash and elution buffer conditions. As all of these factors are explored in the same experiment, the interactions between them are characterized and the number of follow‐up confirmatory experiments is reduced. This in turn improves statistical power and throughput. Two examples of the IBC method are shown and the impact of the load conditions are assessed in combination with the other factors explored.
Sortase A‐mediated synthesis of ligand‐grafted cyclized peptides for modulating a model protein‐protein interaction
Authors: Zhang Jing , Yamaguchi Satoshi , Nagamune Teruyuki 
Published: April 2015

AbstractSpecific ligand‐grafted cyclic peptides are promising drug candidates that can modulate protein‐protein interactions (PPIs) with increased proteolytic stability. In this study, we aimed to demonstrate that Sortase A (SrtA)‐mediated peptide transpeptidation can be applied to produce bioactive sequence‐grafted, stable, cyclic peptides. A naturally occurring cyclic peptide, sunflower trypsin inhibitor 1 (SFTI‐1), was selected as the scaffold, and a tetrapeptide motif, Glu‐Ser‐Asp‐Val (ESDV), was grafted into the scaffold as a model ligand. The linear precursor of the grafted peptide with SrtA‐recognition motifs at the N‐ and C‐termini was cyclized in good yield simply by co‐incubation with SrtA. The ESDV‐grafted cyclic SFTI‐1 obtained was confirmed to have high stability against proteolysis by human serum and bound to the target PDZ2 domain of postsynaptic density‐95 protein. An optimized sequence‐grafted cyclic SFTI‐1 could competitively suppress the interaction of PDZ2 with its natural ligand, the C‐terminal peptide of the NR2B subunit of the N‐methyl‐D‐aspartate receptor. These results show that a strategy combining peptide grafting into the SFTI‐1 scaffold with SrtA‐catalyzed cyclization can be a simple and effective method for producing stable peptide drugs.
Activity‐Fed Translation (AFT) Assay: A New High‐Throughput Screening Strategy for Enzymes in Droplets
Authors: Woronoff Gabrielle , Ryckelynck Michaël , Wessel Julia , Schicke Olivier , Griffiths Andrew D. , Soumillion Patrice 
Published: April 2015

AbstractThere is an increasing demand for the development of sensitive enzymatic assays compatible with droplet‐based microfluidics. Here we describe an original strategy, activity‐fed translation (AFT), based on the coupling of enzymatic activity to in vitro translation of a fluorescent protein. We show that methionine release upon the hydrolysis of phenylacetylmethionine by penicillin acylase enabled in vitro expression of green fluorescent protein. An autocatalytic setup where both proteins are expressed makes the assay highly sensitive, as fluorescence was detected in droplets containing single PAC genes. Adding a PCR step in the droplets prior to the assay increased the sensitivity further. The strategy is potentially applicable for any activity that can be coupled to the production of an amino acid, and as the microdroplet volume is small the use of costly reagents such as in vitro expression mixtures is not limiting for high‐throughput screening projects.
Bivalirudin versus heparin in patients with acute myocardial infarction: A meta‐analysis of randomized trials
Authors: Ferrante Giuseppe , Valgimigli Marco , Pagnotta Paolo , Presbitero Patrizia 
Published: April 2015

BackgroundThe aim of this study was to assess the impact of bivalirudin, as compared to unfractionated heparin, on clinical outcomes in patients with ST‐segment elevation myocardial infarction (STEMI).MethodsA meta‐analysis of randomized trials comparing bivalirudin versus heparin in patients with STEMI undergoing primary percutaneous coronary intervention was performed. Three randomised trials enrolling 7,612 patients were included. Analysis was by intention to treat.ResultsAt 30 days, bivalirudin, as compared to heparin, was associated with a similar risk of all‐cause mortality (3.03% vs. 3.38%, odds ratio (OR) 0.90, 95% confidence intervals (CI) [0.63 to 1.29], P = 0.57). Bivalirudin significantly increased the risk of definite (2.39% vs. 1.06%, OR 2.49, 95% CI [1.30 to 4.76], P = 0.006); definite or probable (2.55% vs. 1.35%, OR 2.26, 95% CI [1.07 to 4.79], P = 0.03), and acute stent thrombosis (1.69% vs. 0.39%, OR 4.34, 95% CI [2.30 to 8.16], P < 0.001); leading to nonsignificantly higher reinfarction rates (2.0% vs. 1.31%, OR 1.72, 95% CI [0.89 to 3.35], P = 0.11), and to a significantly increased risk of ischemia driven revascularization (2.50% vs. 1.52%, OR 1.80, 95% CI [1.02 to 3.18], P = 0.04) at 30 days. No firm evidence for a reduction in major bleeding associated with bivalirudin use was found (3.93% vs. 6.39%, OR 0.63, 95% CI [0.39 to 1.04], P = 0.07).ConclusionsIn patients with STEMI, bivalirudin, as compared to heparin, increases the risk of stent thrombosis and ischemia driven repeat revascularization at 30 days. There is no strong evidence that bivalirudin significantly reduces major bleeding at 30 days. Bivalirudin does not have an effect on all‐cause mortality at 30 days. © 2015 Wiley Periodicals, Inc.
Axial Dispersion and Heat Transfer in a Milli/Microstructured Coiled Flow Inverter for Narrow Residence Time Distribution at Laminar Flow
Authors: Kurt Safa Kutup , Gelhausen Marius Gerrit , Kockmann Norbert 
Published: April 2015

AbstractHelically coiled tubes offer improved residence and thermal time distributions due to the formation of Dean vortices via centrifugal forces. Design and fabrication of several milli/microstructured helically coiled tube reactors are described for processes requiring a narrow residence time distribution (RTD) and efficient heat transfer at laminar flow regime. The performance of microstructured reactor capillaries, which provide a high specific surface area, is combined with a type of helically coiled tube, namely, a coiled flow inverter allowing for the narrowest RTD in laminar flow regimes. Axial dispersion is characterized by obtaining the RTD curves from different reactor setups. Overall heat transfer coefficients of a new reactor setup are measured in order to determine the heat transfer efficiency.