bluuebunny/crossref_metadata_2025_split huggingface dataset:
Origins of the solvent effect on the propagation kinetics of acrylic acid and methacrylic acid
Authors: Degirmenci Isa. , Ozaltın Tugba Furuncuoglu , Karahan Ozlem , Van Speybroeck Veronique , Waroquier Michel. , Aviyente Viktorya 
Published: February 2013

AbstractIn this study, the relative rate of polymerization of acrylic acid (AA) versus methacrylic acid (MAA) and the effect of water on the polymerization kinetics are investigated within a combined static and molecular dynamics set of computational tools. Experimentally the relative rate of propagation of AA versus MAA is around 35 in bulk and 31 in water. Classical Molecular Dynamics calculations have been carried out to determine the location of the solvent molecules in the proximity of the dimeric poly(AA) and poly(MAA) units. A combined implicit/explicit solvent model was used for the evaluation of the kinetics of the dimeric polymer chains. We show that the rate acceleration of both polymers in water is mainly due to entropic rather than electrostatic effects and is in agreement with experimental findings. Moreover the slower propagation rate of MAA versus AA is ascribed to additional steric effects present in MAA due to the methyl group at the α position of the monomer. Among the functionals used, the M06‐2X/6‐311+G(3df,2p)//B3LYP/6‐31+G(d) methodology reproduces the experimental rate constants quantitatively the best. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
Effect of local irradiation with 630 and 860 nm low-level lasers on tympanic membrane perforation repair in guinea pigs
Authors: Maleki Sh , Kamrava S K , Sharifi D , Jalessi M , Asghari A , Ghalehbaghi S , Yazdanifard P 
Published: February 2013

AbstractObjective:In this study, we evaluated the effect of low-level lasers on the healing of tympanic membrane perforation, one of the most common otological pathologies.Methods and materials:Twenty-four guinea pigs were randomly assigned to either the experimental or control group. One day after the induction of a 2 mm diameter, centred myringotomy in all animals, the tympanic membranes in the experimental group were irradiated with 630 and 860 nm lasers for 10 days. Two weeks later, histological changes in the membranes were evaluated.Results:Tympanic membrane thickening and inflammatory cell infiltration in the tympanic membranes and surrounding tissues were significantly less in the experimental group (p < 0.001). The distance from the external auditory canal wall to the malleus tip did not differ significantly between the two groups (p = 0.42).Conclusion:The results show that the combined application of 630 and 860 nm lasers had a significant effect on the healing of tympanic membrane perforation, and on the prevention of thick fibrotic or atelectatic neomembrane formation.
Temporal dynamics of spore release of the crayfish plague pathogen from its natural host, American spiny-cheek crayfish (Orconectes limosus), evaluated by transmission experiments
Authors: SVOBODA J. , KOZUBÍKOVÁ-BALCAROVÁ E. , KOUBA A. , BUŘIČ M. , KOZÁK P. , DIÉGUEZ-URIBEONDO J. , PETRUSEK A. 
Published: February 2013

SUMMARYThe crayfish plague pathogen, Aphanomyces astaci, is one of the most serious threats to indigenous European crayfish species. The North American invasive spiny-cheek crayfish, Orconectes limosus, is an important source of this pathogen in central and western Europe. We evaluated potential changes in A. astaci spore release rate from infected individuals of this species by experiments investigating the pathogen transmission to susceptible noble crayfish, Astacus astacus. We filtered defined volumes of water regularly to quantify spore concentration, and sampled crayfish tissues at the end of the experiment. The filters and tissues were then tested for the presence of A. astaci DNA by species-specific quantitative PCR. Additionally, we tested the efficiency of horizontal transmission to apparently uninfected O. limosus. The experiments confirmed that A. astaci can be transmitted to susceptible crayfish during intermoult periods, and that the pathogen was more frequently detected in noble crayfish recipients than in American ones. The pathogen spore concentrations substantially varied in time, and significantly increased during moulting of infected hosts. Our study strengthens the evidence that although the likelihood of crayfish plague transmission by water transfer from localities with infected American crayfish might increase when these are moulting or dying, no time-periods can be proclaimed safe.
Parasite infection and host group size: a meta-analytical review
Authors: PATTERSON JESSE E. H. , RUCKSTUHL KATHREEN E. 
Published: February 2013

SUMMARYMany studies have identified various host behavioural and ecological traits that are associated with parasite infection, including host gregariousness. By use of meta-analyses, we investigated to what degree parasite prevalence, intensity and species richness are correlated with group size in gregarious species. We predicted that larger groups would have more parasites and higher parasite species richness. We analysed a total of 70 correlations on parasite prevalence, intensity and species richness across different host group sizes. Parasite intensity and prevalence both increased positively with group size, as expected. No significant relationships were found between host group size and parasite species richness, suggesting that larger groups do not harbour more rare or novel parasite species than smaller groups. We further predicted that the mobility of the host (mobile, sedentary) and the mode of parasite transmission (direct, indirect, mobile) would be important predictors of the effects of group sizes on parasite infection. It was found that group size was positively correlated with the prevalence and intensity of directly and indirectly transmitted parasites. However, a negative relationship was observed between group size and mobile parasite intensity, with larger groups having lower parasite intensities. Further, intensities of parasites did not increase with group size of mobile hosts, suggesting that host mobility may negate parasite infection risk. The implications for the evolution and maintenance of sociality in host species are discussed, and future research directions are highlighted.
Impact ofHaemophilus influenzaetype b vaccination on the incidence of invasiveHaemophilus influenzaedisease in France, 15 years after its introduction
Authors: GEORGES S. , LEPOUTRE A. , DABERNAT H. , LEVY-BRUHL D. 
Published: February 2013

SUMMARYWe assessed the impact ofHaemophilus influenzaetype b (Hib) vaccination, introduced in France in early 1993, on the incidence of invasiveHaemophilus influenzae(Hi) disease up to 2008. The incidence of Hi meningitis fell from 0·9/100 000 in 1991–1992 to 0·09/100 000 in 1996–2008, with a marked decline (96%) in children aged <5 years, including infants aged <3 months, from 12 to 0·4/100 000. The incidence of invasive Hi disease also decreased in children aged <15 years from 6 to 0·7/100 000, remained stable in the 15–64 years age group at about 0·5/100 000, and increased slightly from 2·0 to 2·4/100 000 in persons aged >64 years. No emergence of non-encapsulated or encapsulated non-vaccine serotypes was observed. These findings confirm the major direct impact of Hib vaccination on the incidence of Hi invasive disease in children and the indirect benefit of vaccination for infants too young to be vaccinated.
Altered Effective Connectivity of the Default Mode Network in Resting-State Amnestic Type Mild Cognitive Impairment
Authors: Yan Hao , Zhang Yumei , Chen Hongyan , Wang Yonghui , Liu Yijun 
Published: February 2013

AbstractAmnestic mild cognitive impairment (aMCI) is the transitional, heterogeneous continuum from normal elderly to Alzheimer's disease (AD). Previous studies have shown that brain functional activity in the default mode network (DMN) is impaired in aMCI patients with saliently cognitive and memory decline. However, the effective connectivity among the spatially isolated, but functionally related areas within the DMN in aMCI patients remains largely unknown. The present study examined dysfunctional connectivity of the DMN by combining an independent component analysis (ICA) approach with multivariate Granger causality analysis (mGCA) in 18 aMCI patients and 18 age-matched cognitively normal elderly. Results from mGCA showed decreased effective connectivity occurred among the middle temporal gyrus (MTG), hippocampus (HC) and fusiform gyrus (FG), as well as between the precuneus/posterior cingulate cortex (PreCN/PCC) and HC in patients with aMCI. Such an impaired connectivity was also correlated with patients’ cognitive performance of the auditory verbal learning. Moreover, enhanced effective connectivity within frontal cortex emerged, which may maintain memory functions after attenuated connections within DMN activity. These findings may elucidate the dysfunctional processes in brain networks of aMCI patients, highlighting the importance of connectivity changes in the pathophysiology of aMCI. (JINS, 2013, 19, 1–10)
Coronal ejection and heating in variable-luminosity X-ray sources
Authors: Kluźniak Włodek 
Published: February 2013

AbstractA sudden increase in stellar luminosity may lead to the ejection of a large part of any optically thin gas orbiting the star. Test particles in circular orbits will become unbound, and will escape to infinity (if radiation drag is neglected), when the luminosity changes from zero to at least one half the Eddington value, or more generally, from L to (LEdd+L)/2 or more. Conversely, a decrease in luminosity will lead to the tightening of orbits of optically thin fluid. Even a modest fluctuation of luminosity of accreting neutron stars or black holes is expected to lead to substantial coronal heating. Luminosity fluctuations may thus account for the high temperatures of the X-ray corona in accreting black hole and neutron star systems.
Experimental evolution of nodule intracellular infection in legume symbionts
Authors: Guan Su Hua , Gris Carine , Cruveiller Stéphane , Pouzet Cécile , Tasse Lena , Leru Aurélie , Maillard Aline , Médigue Claudine , Batut Jacques , Masson-Boivin Catherine , Capela Delphine 
Published: February 2013

Abstract
Soil bacteria known as rhizobia are able to establish an endosymbiosis with legumes that takes place in neoformed nodules in which intracellularly hosted bacteria fix nitrogen. Intracellular accommodation that facilitates nutrient exchange between the two partners and protects bacteria from plant defense reactions has been a major evolutionary step towards mutualism. Yet the forces that drove the selection of the late event of intracellular infection during rhizobium evolution are unknown. To address this question, we took advantage of the previous conversion of the plant pathogen Ralstonia solanacearum into a legume-nodulating bacterium that infected nodules only extracellularly. We experimentally evolved this draft rhizobium into intracellular endosymbionts using serial cycles of legume-bacterium cocultures. The three derived lineages rapidly gained intracellular infection capacity, revealing that the legume is a highly selective environment for the evolution of this trait. From genome resequencing, we identified in each lineage a mutation responsible for the extracellular–intracellular transition. All three mutations target virulence regulators, strongly suggesting that several virulence-associated functions interfere with intracellular infection. We provide evidence that the adaptive mutations were selected for their positive effect on nodulation. Moreover, we showed that inactivation of the type three secretion system of R. solanacearum that initially allowed the ancestral draft rhizobium to nodulate, was also required to permit intracellular infection, suggesting a similar checkpoint for bacterial invasion at the early nodulation/root infection and late nodule cell entry levels. We discuss our findings with respect to the spread and maintenance of intracellular infection in rhizobial lineages during evolutionary times.
Self‐employment as a career strategy for ethnic minorities
Authors: Inal Gözde , Al Ariss Akram , Forson Cynthia 
Published: February 2013

PurposeThe purpose of this paper is to examine the self‐employment process of Turkish‐Cypriot restaurateurs and lawyers in the UK, in particular the way they mobilize resources as a strategic choice for their career transition.Design/methodology/approachThe paper draws on a qualitative empirical research consisting of semi‐structured in‐depth interviews from two different sectors with 20 restaurateurs and lawyers in London.FindingsFindings indicate that Turkish‐Cypriots in Britain deliberately draw on social, economic, cultural, and symbolic forms of capital in order to pursue their career projects. The impact of the interconnectedness and availability of one resource on the participants’ ability to acquire other resources is shown to have a key role in developing and transitioning into careers in self‐employment.Research limitations/implicationsThe number of participants interviewed (20) is limited for the purposes of making generalizations and the paper has a main focus on micro‐individual experiences of individuals.Originality/valueThe limited literature on self‐employment for ethnic minorities is often conceptualized as an option to avoid employment inequalities. This paper offers an understanding of self‐employment as a career strategy for Turkish‐Cypriots in Britain.
Fatigue performance of additive manufactured metallic parts
Authors: Spierings A.B. , Starr T.L. , Wegener K. 
Published: February 2013

PurposeAdditive manufacturing technologies such as, for example, selective laser melting (SLM) offer new design possibilities for a wide range of applications and industrial sectors. Whereas many results have been published regarding material options and their static mechanical properties, the knowledge about their dynamic mechanical behaviour is still low. The purpose of this paper is to deal with the measurement of the dynamic mechanical properties of two types of stainless steels.Design/methodology/approachSpecimens for dynamic testing were produced in a vertical orientation using SLM. The specimens were turned to the required end geometry and some of them were polished in order to minimise surface effects. Additionally, some samples were produced in the end geometry (“near net shape”) to investigate the effect of the comparably rough surface quality on the lifetime. The samples were tension‐tested and the results were compared to similar conventional materials.FindingsThe SLM‐fabricated stainless steels show tensile and fatigue behaviour comparable to conventionally processed materials. For SS316L the fatigue life is 25 per cent lower than conventional material, but lifetimes at higher stress amplitudes are similar. For 15‐5PH the endurance limit is 20 per cent lower than conventional material. Lifetimes at higher stress also are significantly lower for this material although the surface conditions were different for the two tests. The influence of surface quality was investigated for 316L. Polishing produced an improvement in fatigue life but lifetime behaviour at higher stress amplitudes was not significantly different compared to the behaviour of the as‐fabricated material.Originality/valueIn order to widen the field of applications for additive manufacturing technologies, the knowledge about the materials properties is essential, especially about the dynamic mechanical behaviour. The current study is the only published report of fatigue properties of SLM‐fabricated stainless steels.
Study of the inter‐particle necks in selective laser sintering
Authors: Jhabvala Jamasp , Boillat Eric , Glardon Rémy 
Published: February 2013

PurposeSince pulsed lasers are mainly used in selective laser sintering (SLS) – contrarily to selective laser melting (SLM) – only the exterior of the powder particles is molten while their core stays solid. The purpose of this paper is to investigate the binding mechanism between two particles of titanium powder.Design/methodology/approachA dedicated experimental setup is used to isolate the particles. They are then irradiated by the laser. SEM micrographs are taken at each step and image analysis is performed. The obtained results are compared with the predictions of a thermal model allowing for the incorporation of the latent heat of fusion and for a realistic surrounding. The absorbed laser intensity is modeled by means of the Mie theory.FindingsThe growing of the interparticular necks and the volume of liquid formed for different repetition rates are measured and compared with numerical simulations. A good agreement is found. A new method to easily find the absorption coefficient of the laser into the grain and the heat exchange coefficient with the exterior is developed.Originality/valueThis paper leads to a better understanding of the necking phenomena involved in the SLS consolidation process. An experimental set‐up has been developed to observe and quantify the final state of a small amount of laser sintered grains. This process has been shown to be replicable and trustful. The thermal model leads to good predictions of the particle final sintering state.
Implementation of Hyogo Framework for Action in Makati City, Philippines
Authors: Matsuoka Yuki , Takeuchi Yukiko , Shaw Rajib 
Published: February 2013

PurposeThe purpose of this paper is to review the challenges for disaster risk reduction (DRR) by local governments and local implementation of the Hyogo Framework for Action (HFA) as the global DRR guideline.Design/methodology/approachBased on a survey on 20 tasks identified in “A guide for implementing HFA by local stakeholders”, HFA implementation by local government is analyzed to identify priorities and the gaps. The target group for the detail analysis was the Makati city DRR coordinating council (MCDRRCC).FindingsThe survey reviewed how multi‐stakeholders involved in local DRR perceive these HFA 20 tasks, which revealed trends and gaps within their work. The result showed that Makati currently places more emphasis on HFA 1, but revealed some gaps in the area of HFA 4. While suggesting a set of recommended actions for Makati, the analysis also revealed how these gaps were addressed in its recent action plan. MDRRCC demonstrated a case for local platform for DRR in terms implementing the actions and addressing the challenges through proper coordination among stakeholders.Research limitations/implicationsSince local HFA implementation is relevantly new area, its applicability needs to be examined further considering linkages between national and local governments.Originality/valueThis paper is unique since the original data were collected from the survey. Makati city case proposes a model of local platform for comprehensive DRR actions along with HFA, which provides value added approach contributing to the ISDR Campaign. The case of Makati provides an on‐going model process of a local platform for DRR which can be leant by other local government for possible replication.
A framework to construct post‐disaster housing
Authors: Patel Saumyang , Hastak Makarand 
Published: February 2013

PurposeNatural disasters often destroy hundreds of homes that leave victims homeless and leads to community displacement. In the USA, such disasters happen over 60 times per year. This leads to logistical and contractual nightmare for the planning agencies and political/community leaders required to provide shelter for displaced citizens. One of the most important challenges for the policy makers and aid providers is to make homes available to the homeless victims in as short a period as possible. Temporary shelter is costly and often excessively delayed. Also quality and long stay (more than four years for the Katrina victims) in temporary shelter affected victims both mentally and physically. The aim of this paper is to propose a strategic framework that assists responsible entities to provide housing to the disaster victims in a short period of time, for example to construct 200 homes in 30 days after disaster (representing a subdivision).Design/methodology/approachThe main objective of this research is to perform feasibility study of implementing such a strategy that would enable agencies to provide better solutions for post disaster housing assistance. This paper mainly explains four phases that constitute the development of the strategic framework. The first two phases of the framework carry out pre‐disaster planning and establish relationships among the participating entities. Whereas, the third phase includes simulating post disaster processes identified in the previous phases to evaluate response trade‐offs. The last phase is about the real implementation of this strategy after disaster that also incorporates its outcomes and experiences into previously planned strategy.FindingsIt was found through second part of research, simulation studies, that such a strategy can be prepared before the disaster and activated when needed. This would drastically reduce the housing response time.Originality/valueThis would help in improving the strategy for future disasters. Successful execution would facilitate opportunities to reduce stress for the victims and encourage faster recovery.
The effect of organizational environment on engineering project cost management
Authors: Mao Hongtao , Zhu Bo , Wang Tian'an 
Published: February 2013

PurposeThe aim of this paper is to examine the effect of organizational environment on engineering project cost management.Design/methodology/approachTaking China Railway Engineering Corporation 2nd Bureau (CREC 2nd Bureau for short) as an example, the authors conduct lots of semi‐structured interviews in its group corporation, company limited, two subsidiaries and two project departments, and finally collect textual data which include 30 paragraphs and more than 120,000 words. The authors then encode those interview data step by step for further analysis under the research paradigm of grounded theory.FindingsBased on these encoded data, the paper builds concept, basic categories, main categories, which could be the factors affecting the engineering project cost management, the evidence chain and the complete story clue among these categories. Then finally constructs a theoretical framework called “3S” for short, which is comprised of the organizational structure supporting system, the control procedure supporting system and the social relation supporting system.Research limitations/implicationsBecause of the insufficient importance placed on engineering project cost management by academics and few theoretical papers, this paper provides a new method for exploring the engineering project cost management and a theoretical reference for further research.Practical implicationsIn this paper, the authors discuss the action mechanism of organizational environment in the engineering project cost management and provide for Chinese construction enterprises more explicit guidance on their cost management practice.Originality/valueThere is little research on determinants of engineering project cost by Chinese scholars, which is mainly shown as normative research. There is no perfect theoretical framework on the determinants of engineering project cost management, which is not beneficial to the knowledge of engineering project cost management and is not comprehensive and in depth enough for academics and practitioners. This paper conducts a field study in CREC 2nd Bureau based on grounded theory. At last, “3S” theoretical framework is established. This paper is embodied in using reality as the accordance, scientifically carding and spreading the theory and translating the practical experience into theory, so that it is beneficial for the engineering project cost management.