bluuebunny/crossref_metadata_2025_split huggingface dataset:
Composition effects of thermoplastic segmented polyurethanes on their nanostructuring kinetics with or without preshear
Authors: Mourier Elise , David Laurent , Alcouffe Pierre , Rochas Cyrille , Méchin Françoise , Fulchiron René 
Published: April 2011

AbstractIn this work, the structuring mechanism from the molten state of various thermoplastic polyurethanes was analyzed with respect to their composition [polyether or polyester soft segments (SSs), aromatic or aliphatic hard segments (HSs)]. As a preliminary study, the molar mass evolution of the materials with the temperature was quantified. Then, based on rheological experiments and in situ rheo‐small angle X‐ray scattering (SAXS) measurements, the structuring was examined at different temperatures and, particularly, the effect of a preshear treatment was analyzed. The temperature effect can be accounted by an Arrhenius‐like law with an activation energy depending mainly on the HS nature. Moreover, the shear induced structuring phenomenon is highlighted for all the studied thermoplastic segmented polyurethanes. Nevertheless, for the studied range of shear treatments, the SAXS analyses did not reveal any specific orientation. Finally, arguments based on the modification of the quench depth (ΔT = TODT − T) by the shear are given to explain the shear induced structuring phenomenon. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011
Modulating repeat protein stability: The effect of individual helix stability on the collective behavior of the ensemble
Authors: Cortajarena Aitziber L. , Mochrie Simon G. J. , Regan Lynne 
Published: April 2011

AbstractRepeat proteins are tandem arrays of a small structural motif, in which tertiary structure is stabilized by interactions within a repeat and between neighboring repeats. Several studies have shown that this modular structure is manifest in modular thermodynamic properties. Specifically, the global stability of a repeat protein can be described by simple linear models, considering only two parameters: the stability of the individual repeated units (H) and the coupling interaction between the units (J). If the repeat units are identical, single values of H and J, together with the number of repeated units, is sufficient to completely describe the thermodynamic behavior of any protein within a series. In this work, we demonstrate how the global stability of a repeat protein can be changed, in a predictable fashion, by modifying only the H parameter. Taking a previously characterized series of consensus tetratricopeptide repeats (TPR) (CTPRa) proteins, we introduced mutations into the basic repeating unit, such that the stability of the individual repeat unit was increased, but its interaction with neighboring units was unchanged. In other words, we increased H but kept J constant. We demonstrated that the denaturation curves for a series of such repeat proteins can be fit and additional curves can be predicted by the one‐dimensional Ising model in which only H has changed from the original fit for the CTPRa series. Our results show that we can significantly increase the stability of a repeat protein by rationally increasing the stability of the units (H), whereas the interaction between repeats (J) remains unchanged.
Coarse‐grained modeling of conformational transitions underlying the processive stepping of myosin V dimer along filamentous actin
Authors: Zheng Wenjun 
Published: April 2011

AbstractTo explore the structural basis of processive stepping of myosin V along filamentous actin, we have performed comprehensive modeling of its key conformational states and transitions with an unprecedented residue level of details. We have built structural models for a myosin V monomer complexed with filamentous actin at four biochemical states [adenosine diphosphate (ATP)‐, adenosine diphosphate (ADP)‐phosphate‐, ADP‐bound or nucleotide‐free]. Then we have modeled a myosin V dimer (consisting of lead and rear head) at various two‐head‐bound states with nearly straight lever arms rotated by intramolecular strain. Next, we have performed transition pathway modeling to determine the most favorable sequence of transitions (namely, phosphate release at the lead head followed by ADP release at the rear head, while ADP release at the lead head is inhibited), which underlie the kinetic coordination between the two heads. Finally, we have used transition pathway modeling to reveal the order of structural changes during three key biochemical transitions (phosphate release at the lead head, ADP release and ATP binding at the rear head), which shed lights on the strain‐dependence of the allosterically coupled motions at various stages of myosin V's work cycle. Our modeling results are in agreement with and offer structural insights to many results of kinetic, single‐molecule and structural studies of myosin V. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Application of cycleave PCR to the detection of a point mutation (F167Y) in the β2‐tubulin gene of Fusarium graminearum
Authors: Hou Yiping , Luo Qingquan , Chen Changjun , Zhou Mingguo 
Published: April 2011

AbstractBACKGROUND: Resistance of Fusarium graminearum to the benzimidazole fungicide carbendazim is caused by point mutations in the β2‐tubulin gene (FGSG_06611.3). The point mutation at codon 167 (TTT → TAT, F167Y) occurs in more than 90% of field isolates in China. It is important to find a suitable method for rapid detection and quantification of this point mutation in the F. graminearum populations.RESULTS: A pair of primers, Codon167F/Codon167R, were designed to amplify a fragment containing the mutation site, and two cycling probes labelled with different fluorescent reporters were used to detect whether the mutation was present. A cycleave real‐time PCR method was developed for rapid determination of the frequency of this point mutation in 282 F. graminearum perithecia collected from different fields in Jiangsu Province, China. The mutation frequency in ascospores from the perithecia to carbendazim by a spore germination assay was 6.0%, while the frequency of the point mutation at codon 167 by the cycleave real‐time PCR assay was 3.9%.CONCLUSION: The cycleave real‐time PCR method is suitable for accurate detection of the codon 167 point mutation. The frequency of this mutation in the β2‐tubulin gene represents the resistance frequency in F. graminearum populations to carbendazim. Copyright © 2011 Society of Chemical Industry
Biological control of red rot in sugarcane by native pyoluteorin‐producing Pseudomonas putida strain NH‐50 under field conditions and its potential modes of action
Authors: Hassan Muhammad N , Afghan Shahid , Hafeez Fauzia Y 
Published: April 2011

AbstractBACKGROUND: Rhizobacteria have a good potential to suppress soilborne diseases, but their efficacy against sugarcane pests is rarely reported. Bacterial strains isolated from the rhizosphere of sugarcane were evaluated for their potential to suppress red rot disease on two susceptible varieties, Co‐1148 and SPF‐234, under field conditions. The strains were also characterised for the production of secondary metabolites associated with their antagonistic activity.RESULTS: One out of four strains, the Pseudomonas putida strain NH‐50 (EU627168), reduced disease severity by 44–60% in different field trials. This potent antagonistic strain produced pyoluteorin antibiotic, as confirmed by high‐performance liquid chromatography (HPLC). The PltB gene involved in pyoluteorin synthesis was amplified from the P. putida strain NH‐50 and sequenced. The extracellular metabolites and volatile and diffusible antibiotics secreted by the tested strains inhibited mycelial growth of Glomerella tucumensis (Speg.) Arx & E Mull in vitro by 7–55%.CONCLUSION: The pyoluteorin‐producing bacteria P. putida strain NH‐50 significantly reduced disease severity on both sugarcane varieties, irrespective of fungal inoculation, i.e. either inoculated through stem or through soil. This strain also possesses other plant growth characteristics and can be used as a biopesticide for sugarcane crop. Copyright © 2011 Society of Chemical Industry
Glyphosate‐resistant horseweed made sensitive to glyphosate: low‐temperature suppression of glyphosate vacuolar sequestration revealed by 31P NMR
Authors: Ge Xia , d'Avignon Dana André , Ackerman Joseph JH , Duncan Bill , Spaur Marvin B , Sammons Robert Douglas 
Published: April 2011

AbstractBACKGROUND: Horseweed has been the most invasive glyphosate‐resistant (GR) weed, spreading to 16 states in the United States and found on five continents. The authors have previously reported that GR horseweed employs rapid vacuolar sequestration of glyphosate, presumably via a tonoplast transporter, substantively to reduce cytosolic glyphosate concentrations.1 It was hypothesized that glyphosate sequestration was the herbicide resistance mechanism. If resistance is indeed endowed by glyphosate sequestration, suppression of sequestration offers the potential for controlling GR horseweed at normal herbicide field‐use rates.RESULTS: Low‐temperature 31P NMR experiments performed in vivo with GR cold‐acclimated horseweed showed markedly suppressed vacuolar accumulation of glyphosate even 3 days after glyphosate treatment. [In stark contrast, 85% of the visible glyphosate was sequestered 24 h after spraying warm‐acclimated GR horseweed.] Cold‐acclimated GR horseweed treated at normal use rates and maintained at low temperature succumbed to the lethal effects of glyphosate over a 40 day period. Treatment of GR horseweed in the field when temperatures were cooler showed the predicted positive herbicidal response.CONCLUSIONS: Low temperature markedly diminishes vacuolar sequestration of glyphosate in the GR horseweed biotype, yielding a herbicide response equivalent to that of the sensitive biotype. This supports the recent hypothesis1 that glyphosate sequestration is the resistance mechanism employed by GR horseweed. Copyright © 2011 Society of Chemical Industry
Towards an improved understanding of the dynamics of vineyard‐infesting Scaphoideus titanus leafhopper populations for better timing of management activities
Authors: Rigamonti Ivo E , Jermini Mauro , Fuog Daniele , Baumgärtner Johann 
Published: April 2011

AbstractBACKGROUND: This paper deals with supervised management of Scaphoideus titanus (Homoptera Cicadellidae) and describes a phenology model designed for improving the understanding of the within‐vineyard dynamics and the timing of insect growth regulator (IGR) applications.RESULTS: The model consists of five components dealing with (a) the beginning of the post‐dormancy development of overwintering eggs, (b) the egg hatching patterns, (c) the duration of first‐instar nymphs, (d) the development and survival of subsequent instars and (e) the stochastic development of cohorts and their passage into the adult stage. Laboratory data permitted the parameterisation of temperature‐dependent development and survival functions. Field data consisting mainly of beating tray catches allowed model parameterisation and validation. The model satisfactorily predicts the dynamics of age structures, the beginning as well as the pattern of egg hatching, the occurrence of the third instar and the emergence of adults.CONCLUSION: The phenology model is useful for timing IGR applications and for setting up monitoring activities in supervised S. titanus control. The model is an entry point into an adaptive management system, in that real‐time weather and monitoring data are continuously integrated into the model for improving its explanatory and predictive capabilities. Copyright © 2011 Society of Chemical Industry
Electron transport in bulk GaAsN
Authors: Vogiatzis N. , Rorison J.M. 
Published: April 2011

AbstractWe present theoretical results on the steady state characteristics of bulk GaAs1–xNx using the single electron Monte‐Carlo method (x ≤ 0.4%). Two equivalent models are used. The first includes a GaAs band with a strong localized nitrogen resonance. The second model uses the band anti‐crossing model, in which the localized N level interacts with the GaAs band strongly perturbing the conduction band. We obtain two negative differential velocity peaks from the first model which we associate with N scattering and polar optical phonon emission (POPem). From the second model only one peak is obtained associated with POPem. The first model gives very good agreement with experimental low field mobility. We use this model to include additional scattering resonances related with the pair and larger cluster nitrogen states. Further reduction of the mobility and convergence towards the experimental values is observed.
Electrical properties of polycrystalline CaB6 under high pressure and low temperature
Authors: Li Yan , Yang Jie , Cui Xiaoyan , Hu Tingjing , Liu Cailong , Tian Yongjun , Liu Hongwu , Han Yonghao , Gao Chunxiao 
Published: April 2011

AbstractCarrier behavior of CaB6 powders was investigated by using in situ Hall effect measurement under high pressure and resistivity property was detected under low temperature with microcircuit fabricated on diamond anvil cell. Carrier behavior was analyzed by carrier concentration and Hall coefficient. The variation of defects in the grain boundary region lead the carrier concentration and the Hall coefficient in the decompression process are much lower than that in the compression process. The resistivity depended temperature at various pressures indicated that CaB6 has a typical metallic behavior under high pressure.
Temperature‐dependent study of the Raman A mode of Cu2ZnSnS4 thin films
Authors: Sarswat Prashant K. , Free Michael L. , Tiwari Ashutosh 
Published: April 2011

AbstractThis temperature‐dependent Raman study of kesterite phase Cu2ZnSnS4 (CZTS) thin film was performed over the temperature range 98–378 K. A detailed qualitative analysis showed that the Raman data for the “A” mode of vibration, the strongest peak for kesterite CZTS films, fit very well to a damped harmonic oscillator (DHO) model. This investigation of temperature‐dependent Raman data shows that the observed frequency shift is due to the cumulative effect of thermal expansion and anharmonicity resulting from a 4‐phonon damping process. The temperature dependence of linewidth is also consistent with the above analysis.
Study of electronic and elastic properties of β‐HgS under high pressure via first‐principles calculations
Authors: Xiao‐Cui Yang , Jie Yang , En‐Jie Zhang , Chun‐Xiao Gao 
Published: April 2011

AbstractAn investigation on the electronic and elastic properties of β‐HgS under high pressure was conducted using first‐principles calculations based on density functional theory with the CASTEP code in MS modeling. Our results demonstrate that the sequence of the pressure‐induced phase transition of HgS is from the zinicblende (β‐HgS, space group F43m) to the cinnabar (α‐HgS, space group P3121) to the rocksalt (space group Fm3m) structure. The calculated transition pressures are reported, which are in good agreement with the available experimental results and the previous theoretical data. The pressure effect on the elastic parameters of HgS in the F43m structure is determined theoretically (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
What qualitative research has taught us about occupational stress
Authors: Mazzola Joseph J. , Schonfeld Irvin Sam , Spector Paul E. 
Published: April 2011

AbstractWhile many reviews of job stress and the stressor–strain relationship have been conducted, such reviews typically focus exclusively on quantitative data. In the current paper, we review qualitative studies on occupational stress that met two criteria: (1) the studies employed qualitative methods; (2) the stressors, strains and/or coping strategies were grouped into identifiable, higher‐order categories. Results indicated that the nature of the stressors experienced varied by (a) occupation, (b) country, (c) seniority and (d) gender. The review further revealed that organizational constraints, work overload and interpersonal conflict were relatively universal stressors. Anger and annoyance were the most frequently reported psychological strains in the United States and the United Kingdom, while Chinese workers exhibited tension and anxiety and Indian workers exhibited acceptance. Coping strategies also varied by gender, occupation and country. Research on gender differences suggested that, compared to men, women tended to report more interpersonal stressors. Differences in the ways in which the two types of methodologies are applied, as well as their relative strengths and weaknesses, underline the value of qualitative approaches to the study of occupational stress, especially when used in conjunction with quantitative methods in mixed‐methods studies. Copyright © 2011 John Wiley & Sons, Ltd.
Manipulating Wi‐Fi packet traces with WiPal: design and experience
Authors: Claveirole Thomas , de Amorim Marcelo Dias 
Published: April 2011

SUMMARYPacket traces are important objects in networking, commonly used in a wide set of applications, including monitoring, troubleshooting, measurements, and validation, to cite a few. Many tools exist to produce and process such traces, but they are often too specific; using them as a basis for creating extended tools is then impractical. Some other tools are generic enough, but exhibit performance issues. This paper reports on our experience designing WiPal, a packet trace manipulation framework with a focus on IEEE 802.11. WiPal is designed for performance and re‐usability, while introducing several novel features compared to previous solutions. Besides presenting how WiPal's original design can benefit packet processing programs, we discuss a number of issues a program designer might encounter when writing packet trace processing software. An evaluation of WiPal shows that, albeit generic, it does not impact performance regarding execution speed. WiPal achieves performance levels observed only with specialized code and outperforms some well‐known packet processing programs. Copyright © 2011 John Wiley & Sons, Ltd.
Fe2MoO4 as a Precursor Material for Mo Alloying in Steel (Part II): Up‐Scaling Test
Authors: Chychko A. , Teng L. , Nzotta M. , Seetharaman S. 
Published: April 2011

AbstractThe Mo yield when using three different alloying mixtures (MoO3 +C; MoO3 +C + FeOx; and MoO3+ C + CaO) was tested both in laboratory experiments (16 g and 0.5 kg scale) and industrial trials (3 ton scale). The alloying is based on in‐situ formation of compounds of Mo in the mixtures from molybdenite concentrate with industrial grade Fe2O3. Thermogravimetry (TGA) and X‐ray diffraction (XRD) analyses were performed to identify the reduction steps and final products of the alloying mixtures. At least two steps of mass change were discovered during the reduction of all tested mixtures by carbon. The Mo yield for MoO3 + C mixture is 93% which was confirmed by both laboratory and industrial experiments. The Mo yield for MoO3 + C + CaO mixture is around 92% during 16 g scale laboratory and 3 ton scale industrial tests. The best results were obtained in the case of the mixture which contained FeOx, MoO3 and C, resulting in the Mo yield up to 98% at all the experiment scale levels. It was found that the combination of both lower evaporation and fast reduction by carbon of the mixture along with further dissolution in steel are necessary to provide high Mo yield during steel alloying. The calculated mass balance of 3 ton trial heats showed that only a small part of initial Mo amount (8–13 ppm) has gone into slag.
Processing and Characterization of Dual Phase Steel Foams Featured by Different Pore Distribution
Authors: Castrodeza Enrique M. , Gruttadauria Andrea , Mapelli Carlo , Mombelli Davide 
Published: April 2011

AbstractPorous materials featuring cellular structures are known to have many interesting combinations of physical and mechanical properties. Some of them have been extensively used in structural applications (i.e. balsa wood), as well as in functional applications (heat exchangers, filters, etc.). Steel foams present promising theoretical properties for both functional and structural applications, but processing such kind of foams is complex due to their high melting temperature. Starting from a technique based on molten metal infiltration into a ceramic space holder, a new process is presented here for open‐cell steel sponges processing. Using a SiC cellular preforms as a space holder, dual phase steels foams with different porosity and steel microstructure were successfully developed.This technique is suitable to obtain steel alloy sponges featured by a relative density equal to 0,6 and interconnected pores. The compression tests indicate that the resulting material features the typical stress‐strain behaviour of classical cellular metals. Moreover mechanical properties, such as Elastic Modulus, σplateau, εdensification and Eabsorbed, depended on porosity and on martensite fraction, which is a function of the applied intercritical temperature.
Extending the investment development path model to include the human environment factor
Authors: Jiuhua Zhu Cherrie , Thomson S. Bruce , Hutchings Kate , Cieri Helen De 
Published: April 2011

AbstractThis article aims to address Dunning's call to include the “human environment” (HE) as a new trend and trajectory for research in international business (IB). Dunning argues that the most important driver for economic advancement is knowledge, which arises from the HE. We extend Dunning's IB theory of the five stages of a country's investment development path (IDP) to include the HE factor. Further, we use China as an example in which to examine the role of human resource management (HRM). We identify and analyze an important link between foreign direct investment, multinational enterprises, and both domestic and global HRM. © 2011 Wiley Periodicals, Inc.
Understanding the rise of global protectionism
Authors: Enderwick Peter 
Published: April 2011

AbstractThe past three decades are generally regarded as a period of widespread liberalization and high growth within the world economy. On a wide range of measures, this era has seen the rapid globalization of business and the lifting from poverty of a large number of the world's poorest, particularly within large emerging markets such as China and India. While the undoubted benefits of globalization are widely recognized for raising economic growth rates and engaging a much larger number of nations in international business activity, globalization has always had its critics. The purpose of this article is to explore the recent rise in protectionism—what has been termed “global protectionism”— to examine how it differs from traditional forms of trade protectionism, and to offer some tentative assessment of its determinants. ©2011 Wiley Periodicals, Inc.
Chinese host country nationals' willingness to help expatriates: The role of social categorization
Authors: Varma Arup , Budhwar Pawan , Pichler Shaun 
Published: April 2011

AbstractIn this study, we examine Chinese host country nationals' (HCNs') willingness to offer role information and social support to expatriates from the United States. Using data from 132 Chinese managers, we find that ethnocentrism, interpersonal affect, and guanxi significantly impact HCNs' willingness to offer help to expatriates. Furthermore, we find that the job level of the expatriate has a significant impact on HCNs' willingness to offer role information but not on willingness to offer social support. The results suggest that paying attention to the perceptions and reactions of HCNs toward expatriates is imperative for multinational companies if expatriates are to succeed on their assignments. ©2011 Wiley Periodicals, Inc.