bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigating the impact of non‐Newtonian blood models within a heart pump
Authors: Al‐Azawy Mohammed G. , Turan A. , Revell A. 
Published: February 2016

SummaryA detailed computational fluid dynamics (CFD) study of transient, turbulent blood flow through a positive displacement left ventricular assist device is performed. Two common models for non‐Newtonian blood flow are compared to the Newtonian model to investigate their impact on predicted levels of shear rate and wall shear stress. Given that both parameters are directly relevant to the evaluation of risk from thrombus and haemolysis, there is a need to assess the sensitivity to modelling non‐Newtonian flow effects within a pulsatile turbulent flow, in order to identify levels of uncertainly in CFD. To capture the effects of turbulence, the elliptic blending Reynolds stress model is used in the present study, on account of superior performance of second moment closure schemes previously identified by the present authors. The CFD configuration includes two cyclically rotating valves and a moving pusher plate to periodically vary the chamber volume. An overset mesh algorithm is used for each instance of mesh motion, and a zero gap technique was employed to ensure full valve closure. The left ventricular assist device was operated at a pumping rate of 86 BPM (beats per minute) and a systolic duration of 40% of the pumping cycle, in line with existing experimental data to which comparisons are made. The sensitivity of the variable viscosity models is investigated in terms of mean flow field, levels of turbulence and global shear rate, and a non‐dimensional index is used to directly evaluate the impact of non‐Newtonian effects. The clinical relevance of the results is reported along with a discussion of modelling uncertainties, observing that the turbulent kinetic energy is generally predicted to be higher in non‐Newtonian flow than that observed in Newtonian flow. Copyright © 2016 John Wiley & Sons, Ltd.
Random walk analysis for reflection and transmission of turbid media
Authors: Rogers Geoffrey 
Published: February 2016

AbstractThe reflection and transmission of light from a turbid slab is determined by considering a photon random walk within the medium. The reflection and transmission is obtained using the Beer‐Lambert law on each path through the slab. Path length probability densities are derived, then all paths are summed weighted by their probabilities. The results are simple expressions for the reflection and the transmission in terms of the physical properties of the medium. © 2016 Wiley Periodicals, Inc. Col Res Appl, 41, 580–584, 2016
A distributed and multi‐tiered software architecture for assessing e‐Commerce recommendations
Authors: Palopoli Luigi , Rosaci Domenico , Sarné Giuseppe M. L. 
Published: February 2016

SummaryRecently, an ever increasing number of e‐Commerce tools has been made available that are able to help customers by generating purposed recommendations. Many of them are centralized so that they have to face problems related to efficiency and scalability. A few of them are distributed, but in this case, the complexity of the e‐Commerce process implies computation overhead on the client side, which is often unsuitable if mobile devices are used by customers. In this paper, we study how the software distribution in recommender systems affects their performances, depending on the characteristics of the e‐Commerce population. To this end, we present a distributed testbed architecture for e‐Commerce recommender systems using a multi‐tiered agent‐based approach to generate effective recommendations without requiring such an onerous amount of computation per single client. We use such a testbed to study the main advantages and limitations associated with the problem of distributing the computation of recommendations. Copyright © 2016 John Wiley & Sons, Ltd.
On designing and testing distributed virtual environments
Authors: Valadares Arthur , Gabrielova Eugenia , Lopes Cristina Videira 
Published: February 2016

SummaryDistributed real‐time (DRT) systems are among the most complex software systems to design, test, maintain, and evolve. The existence of components distributed over a network often conflicts with real‐time requirements, leading to design strategies that depend on domain‐specific and even application‐specific knowledge. Distributed virtual environment (DVE) systems are DRT systems that connect multiple users instantly with each other and with a shared virtual space over a network. DVE systems deviate from traditional DRT systemsx in the importance of the quality of the end user experience. We present an analysis of important, but challenging, issues in the design, testing, and evaluation of DVE systems through the lens of experiments with a concrete DVE, OpenSimulator. We frame our observations within six dimensions of well‐known design concerns: correctness, fault tolerance/prevention, scalability, time sensitivity, consistency, and overhead of distribution. Furthermore, we place our experimental work in a broader historical context, showing that these challenges are intrinsic to DVEs and suggesting lines of future research. Copyright © 2016 John Wiley & Sons, Ltd.
Tracer‐Based Metabolic NMR‐Based Flux Analysis in a Leukaemia Cell Line
Authors: Carrigan John B. , Reed Michelle A. C. , Ludwig Christian , Khanim Farhat L. , Bunce Christopher M. , Günther Ulrich L. 
Published: February 2016

AbstractHigh levels of reactive oxygen species (ROS) have a profound impact on acute myeloid leukaemia cells and can be used to specifically target these cells with novel therapies. We have previously shown how the combination of two redeployed drugs, the contraceptive steroid medroxyprogesterone and the lipid‐regulating drug bezafibrate exert anti‐leukaemic effects by producing ROS. Here we report a 13C‐tracer‐based NMR metabolic study to understand how these drugs work in K562 leukaemia cells. Our study shows that [1,2‐13C]glucose is incorporated into ribose sugars, indicating activity in oxidative and non‐oxidative pentose phosphate pathways alongside lactate production. There is little label incorporation into the tricarboxylic acid cycle from glucose, but much greater incorporation arises from the use of [3‐13C]glutamine. The combined medroxyprogesterone and bezafibrate treatment decreases label incorporation from both glucose and glutamine into α‐ketoglutarate and increased that for succinate, which is consistent with ROS‐mediated conversion of α‐ketoglutarate to succinate. Most interestingly, this combined treatment drastically reduced the production of several pyrimidine synthesis intermediates.
Synthesis of 1,2‐Dicarbonyl‐3‐enes by Hydroacylation of 1‐Alkynes with Glyoxal Derivatives Using Metal–Organic Framework Cu/MOF‐74 as Heterogeneous Catalyst
Authors: Nguyen Nguyen B. , Dang Giao H. , Le Dung T. , Truong Thanh , Phan Nam T. S. 
Published: February 2016

AbstractA crystalline copper‐based metal–organic framework Cu/MOF‐74 was synthesized, and used as an efficient heterogeneous catalyst for the synthesis of 1,2‐dicarbonyl‐3‐enes by means of the hydroacylation of 1‐alkynes with glyoxal derivatives in the presence of a base. Cu/MOF‐74 was found to be more catalytically active for the synthesis of 1,2‐dicarbonyl‐3‐enes than other MOFs including Cu2(BDC)2(DABCO), Cu3(BTC)2, Cu(BDC), Cu2(NDC)2(DABCO), Cu4I4(DABCO)2, Ni‐MOF‐74, Zn‐MOF‐74, Fe3O(BDC)3, In(OH)(BDC), and Zr6O4(OH)4(BDC)6. Cu/MOF‐74 also exhibited better performance than other homogeneous copper catalysts, including Cu(OAc)2, Cu(NO3)2, CuI, CuBr, CuCl, CuCl2, and CuBr2. The Cu/MOF catalyst was able to be recovered and reused several times without a significant degradation in catalytic activity. To the best of our knowledge, the formation of 1,2‐dicarbonyl‐3‐enes has not previously been carried out under heterogeneous catalysis conditions.
Streaming Complex Plasmas: Ion Susceptibility for a Partially Ionized Plasma in Parallel Electric and Magnetic Fields
Authors: Kählert H. , Joost J. P. , Ludwig P. , Bonitz M. 
Published: February 2016

AbstractThe density response function for streaming ions in homogeneous, parallel electric and magnetic fields is derived self‐consistently from kinetic theory. Ion‐neutral collisions are treated with the Bhatnagar‐Gross‐Krook collision operator assuming a constant ion‐neutral collision frequency. The result accounts for the non‐Maxwellian distribution function of the ions and is valid in the full range from weak to strong magnetization. It provides the basis for various linear response calculations in the context of magnetized complex plasmas, where streaming ions interact with highly charged dust particles under the influence of a strong external magnetic field. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Voids in Dusty Plasma of a Stratified DC Glow Discharge in Noble Gases
Authors: Fedoseev A. V. , Sukhinin G. I. , Abdirakhmanov A. R. , Dosbolayev M. K. , Ramazanov T. S. 
Published: February 2016

AbstractExperimental investigations of dusty plasma parameters of a DC glow discharge were performed in helium and argon. In the discharge in helium, at high discharge current dust‐free regions (voids) were formed in the center of the dust particles clouds that levitated in the strong electric field of a stratified positive column. In experiments with argon, the dust particles were moved from the center of the discharge tube to the periphery at high discharge current. The behavior of voids formation was investigated for different discharge conditions (sort of gas, discharge pressure and discharge current) and dust particles parameters (particles radii and particles total number). It was shown that it is the ion drag force radial component that leads to the formation of voids in helium and moves the particles to the tube periphery in argon discharge. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Streptamer technology allows accurate and specific detection of CMV‐specific HLA‐A*02 CD8+ T cells by flow cytometry
Authors: Ciáurriz Miriam , Beloki Lorea , Bandrés Eva , Mansilla Cristina , Zabalza Amaya , Pérez‐Valderrama Estela , Lachén Mercedes , Ibáñez Berta , Olavarría Eduardo , Ramírez Natalia 
Published: February 2016

BackgroundMultimer technology is widely used to screen antigen‐specific immune recovery after allogeneic hematopoietic stem cell transplantation (allo‐HSCT) as it enables identification, enumeration, phenotypic characterization and isolation of virus‐specific T‐cells. Novel approaches of multimerization might improve on classical tetramer staining; however, their use as standard monitoring technique to quantify antigen‐specific cells has not been validated yet. We have compared two of these available multimeric complexes: pentamer and streptamer to select the best strategy for the incorporation into clinical monitoring practice.MethodsCMVpp65495‐503‐specific HLA‐A*02:01 CD8+ T lymphocytes (CTLA*02:01‐CMVpp65495‐503) were examined with pentamer and streptamer in peripheral blood cells of 77 healthy volunteers. Quantitative and qualitative analyses were performed to compare the precision and repeatability, sensitivity and accuracy and specificity of both technologies by flow cytometry.ResultsStandard deviation for both techniques was less than 0.05 showing that they are repetitive and precise. Both techniques significantly correlated at high frequencies (rSpearman = 0.9422; P < 0.0001) but it was lost at lower levels (<1%) of CTLA*02:01‐CMVpp65495‐503 (rSpearman = 0.3351; P = 0.1376). Streptamer is more accurate for the detection of CTLA*02:01‐CMVpp65495‐503 providing significantly closer values to the theoretical ones (P < 0.0001) as pentamer binds unspecifically to a notable proportion of non‐CMV‐specific CD8+ T‐cells.ConclusionOur results suggest that streptamer multimer provides precise, accurate and specific results to detect CTLA*02:01‐CMVpp65495‐503 by flow cytometry. Streptamer multimer can be used not only for the monitoring of early CTLA*02:01‐CMVpp65495‐503 reconstitution in immunosuppressed patients following allo‐HSCT but also, in conjunction with its reversibility role, for the isolation of CTLA*02:01‐CMVpp65495‐503 for its future use in adoptive immunotherapy. © 2016 International Clinical Cytometry Society
Combinatorial decoding of the invariant C. elegans embryonic lineage in space and time
Authors: Zacharias Amanda L. , Murray John Isaac 
Published: February 2016

SummaryUnderstanding how a single cell, the zygote, can divide and differentiate to produce the diverse animal cell types is a central goal of developmental biology research. The model organism Caenorhabditis elegans provides a system that enables a truly comprehensive understanding of this process across all cells. Its invariant cell lineage makes it possible to identify all of the cells in each individual and compare them across organisms. Recently developed methods automate the process of cell identification, allowing high‐throughput gene expression characterization and phenotyping at single cell resolution. In this Review, we summarize the sequences of events that pattern the lineage including establishment of founder cell identity, the signaling pathways that diversify embryonic fate, and the regulators involved in patterning within these founder lineages before cells adopt their terminal fates. We focus on insights that have emerged from automated approaches to lineage tracking, including insights into mechanisms of robustness, context‐specific regulation of gene expression, and temporal coordination of differentiation. We suggest a model by which lineage history produces a combinatorial code of transcription factors that act, often redundantly, to ensure terminal fate. genesis, 2016. © 2016 Wiley Periodicals, Inc. genesis 54:182–197, 2016. © 2016 Wiley Periodicals, Inc.
Vocal coselection in rat pup ultrasonic vocalizations
Authors: Spence Heather R. , Aslam Ali M. , Hofer Myron A. , Brunelli Susan A. , Shair Harry N. 
Published: February 2016

AbstractSelective breeding and natural selection that select for one trait often bring along other correlated traits via coselection. Selective breeding for an infantile trait, high or low call rates of isolation‐induced ultrasonic vocalization of rat pups, also alters functions of some brain systems and emotional behaviors throughout life. We examined the effect of breeding for call rate on acoustic parameters that are of communicative significance. Selecting for higher call rate produced calls of significantly increased amplitude and bandwidth relative to a randomly bred line. Selecting for lower rate produced calls of decreased duration. These nonmorphological, functional trait changes demonstrate enhanced communicatory potential and energy expenditure for the High line and the opposite for the Low line. This demonstration of coselection in a communicatory system suggests an underlying heritable suite of linked acoustic vocalization characteristics that in noisy environments could enhance dam–pup communication and lead to selection of emotionality traits with beneficial responses to stress.
Climatic patterns in the establishment of wintering areas by North American migratory birds
Authors: Pérez‐Moreno Heidi , Martínez‐Meyer Enrique , Soberón Mainero Jorge , Rojas‐Soto Octavio 
Published: February 2016

AbstractLong‐distance migration in birds is relatively well studied in nature; however, one aspect of this phenomenon that remains poorly understood is the pattern of distribution presented by species during arrival to and establishment of wintering areas. Some studies suggest that the selection of areas in winter is somehow determined by climate, given its influence on both the distribution of bird species and their resources. We analyzed whether different migrant passerine species of North America present climatic preferences during arrival to and departure from their wintering areas. We used ecological niche modeling to generate monthly potential climatic distributions for 13 migratory bird species during the winter season by combining the locations recorded per month with four environmental layers. We calculated monthly coefficients of climate variation and then compared two GLM (generalized linear models), evaluated with the AIC (Akaike information criterion), to describe how these coefficients varied over the course of the season, as a measure of the patterns of establishment in the wintering areas. For 11 species, the sites show nonlinear patterns of variation in climatic preferences, with low coefficients of variation at the beginning and end of the season and higher values found in the intermediate months. The remaining two species analyzed showed a different climatic pattern of selective establishment of wintering areas, probably due to taxonomic discrepancy, which would affect their modeled winter distribution. Patterns of establishment of wintering areas in the species showed a climatic preference at the macroscale, suggesting that individuals of several species actively select wintering areas that meet specific climatic conditions. This probably gives them an advantage over the winter and during the return to breeding areas. As these areas become full of migrants, alternative suboptimal sites are occupied. Nonrandom winter area selection may also have consequences for the conservation of migratory bird species, particularly under a scenario of climate change.
Species‐ and site‐specific impacts of an invasive herbivore on tree survival in mixed forests
Authors: Holland E. Penelope , Gormley Andrew M. , Pech Roger P. 
Published: February 2016

AbstractInvasive herbivores are often managed to limit their negative impact on plant populations, but herbivore density – plant damage relationships are notoriously spatially and temporally variable. Site and species characteristics (both plant and herbivore) must be considered when assessing the potential for herbivore damage, making it difficult to set thresholds for efficient management. Using the invasive brushtail possum Trichosurus vulpecula in New Zealand as a case study, we parameterized a generic model to predict annual probability of browse‐induced mortality of five tree species at 12 sites. We compared predicted and observed tree mortality for each species + site combination to establish herbivore abundance – tree mortality thresholds for each site on a single and combined tree species basis. Model results indicated it is likely that possum browse was the primary cause of all tree mortality at nine of the 12 species‐site combinations, allowing us to estimate site‐specific thresholds below which possum population numbers should be reduced and maintained to keep tree mortality under a predetermined level, for example 0.5% per year. The browse model can be used to set site‐ and species‐specific management action thresholds, and can be adapted easily for other plant or herbivore species. Results for multiple plant or herbivore species at a single site can be combined to create conservative, site‐wide management strategies, and used to: determine which sites will be affected most by changes in herbivore abundance; quantify thresholds for herbivore management; and justify expenditure on herbivore control.
Belowground responses to elevation in a changing cloud forest
Authors: Looby Caitlin I. , Maltz Mia R. , Treseder Kathleen K. 
Published: February 2016

AbstractFew studies have investigated how soil fungal communities respond to elevation, especially within TMCF (tropical montane cloud forests). We used an elevation gradient in a TMCF in Costa Rica to determine how soil properties, processes, and community composition of fungi change in response to elevation and across seasons. As elevation increased, soil temperature and soil pH decreased, while soil moisture and soil C:N ratios increased with elevation. Responses of these properties varied seasonally. Fungal abundance increased with elevation during wet and dry seasons. Fungal community composition shifted in response to elevation, and to a lesser extent by season. These shifts were accompanied by varying responses of important fungal functional groups during the wet season and the relative abundance of certain fungal phyla. We suggest that elevation and the responses of certain fungal functional groups may be structuring fungal communities along this elevation gradient. TMCF are ecosystems that are rapidly changing due to climate change. Our study suggests that these changes may affect how fungal communities are structured.
Facile one‐step synthesis of bio‐based AESO resins
Authors: Wang Chengshuang , Ding Liang , He Meng , Wei Jun , Li Juan , Lu Rong , Xie Hongfeng , Cheng Rongshi 
Published: February 2016

In this study, the bio‐based thermosetting resins were synthesized via thiol‐ene coupling between acrylated epoxidized soybean oil (AESO) and different functionality of thiols. The structure of the AESO was carefully examined using FT–IR and 1H‐NMR measurements. The thermal/mechanical properties of the bio‐based thermosetting resins were characterized using DMA, TGA, and tensile test. The DMA results showed that the storage moduli and glass transition temperatures of bio‐based thermosetting resins improved with increment of thiols functionality, meanwhile, the tensile strength, Young's modulus, and thermal stability of the AESO‐based resins also increased.Practical applications: The thermosetting resins were synthesized via thiol‐ene coupling between AESO and different functionality of thiols. This strategy has the potential for the fabrication of eco‐friendly bio‐based materials.The rapid and highly efficient strategy of thiol‐ene coupling was successfully applied for the preparation of eco‐friendly bio‐based thermosetting resins derived from AESO and different functionality of thiols.
Thiyl‐Radical Reactions in Carbo­hydrate Chemistry: From Thiosugars to Glycoconjugate Synthesis
Authors: McSweeney Lauren , Dénès Fabrice , Scanlan Eoin M. 
Published: February 2016

AbstractThiyl‐radical mediated reactions have been extensively investigated for the preparation of carbohydrate derivatives. Due to the mild reaction conditions, high yields and tolerance to a wide range of functional groups, these reactions are ideally suited to the preparation of bioconjugates including glycopeptides and glycoproteins. This microreview covers the various synthetic strategies that have been employed for the preparation of thiosugars, glycoconjugates and glycodendrimers, employing the carbohydrate unit as both the carrier of the thiyl radical and also as the acceptor. Both the inter‐ and intramolecular thiol‐ene and ‐yne processes are presented and discussed. Future perspective and directions for this methodology in glycoscience are also examined.
Chiral Anion Directed Asymmetric Carbocation‐Catalyzed Diels–Alder Reactions
Authors: Ni Shengjun , Ramesh Naidu Veluru , Franzén Johan 
Published: February 2016

AbstractIn recent years the carbocation has re‐emerged as a highly efficient Lewis acid catalyst for a variety of organic transformations. However, the goal of asymmetric carbocation catalysis has so far been out of reach mainly as a result of difficulties associated with the preparation of stable chiral carbocations. Here, we describe developments towards asymmetric carbocation catalysis based on the concept of chiral‐anion‐directed catalysis. Chiral tritylium salts can be conveniently prepared in situ by mixing trityl chloride derivatives with chiral phosphonate, phosphoramide, bis(sulfonyl)amide, and bis(sulfuryl)amide silver or sodium salts. It is shown that the bis(sulfuryl)amide/tritylium ion salt catalyzes the Diels–Alder reaction with an up to 53 % enantiomeric excess.