650 resultados para growth barriers
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This thesis is a step forward in understanding the growth of graphene, a single layer of carbon atoms, by annealing Silicon Carbide (SiC) thin films in Ultra High Vacuum. The research lead to the discovery that the details of the transition from SiC to graphene, providing, for the first time, atomic resolution images of the different stages of the transformation and a model of the growth. The epitaxial growth of graphene developed by this study is a cost effective procedure to obtain this material directly on Si chips, a breakthrough for the future electronic industry.
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Although many immigrants enter the United States with a healthy body weight, this health advantage disappears the longer they reside in the United States. To better understand the complexities of obesity change within a cultural framework, a community-based participatory research (CBPR) approach, PhotoVoice, was used, focusing on physical activity among Muslim Somali women. The CBPR partnership was formed to identify barriers and resources to engaging in physical activity with goals of advocacy and program development. Muslim Somali women (n = 8) were recruited to participate, trained and provided cameras, and engaged in group discussions about the scenes they photographed. Participants identified several barriers, including safety concerns, minimal culturally appropriate resources, and financial constraints. Strengths included public resources and a community support system. The CBPR process identified opportunities and challenges to collaboration and dissemination processes. The findings laid the framework for subsequent program development and community engagement.
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Latinos report less leisure time physical activity (PA) than non–Latino Whites and suffer disproportionately from diseases related to sedentary lifestyle, yet remain underserved and understudied. Gaining a better understanding of PA behavior in Latinos is critical to intervene on this significant public health issue. This article discusses the growing literature on the facilitators and barriers of PA in Latino men and women and reviews recent interventions to promote activity. Apart from acculturation influences, facilitators of PA in Latinos are similar to those of non–Latino Whites, with most research focusing on self-efficacy and social support. Barriers for Latinas, however, are more culturally distinct, such as a focus on caregiving and cultural standards for body shape. Barriers unique to Latino men largely have not been studied. Researchers have adopted a variety of approaches to increase PA, including using promotores and incorporating culturally appropriate activities, and have had mixed success. However, the community and randomized controlled trials almost exclusively included only women. Studies reviewed here suggest that interventions should target culturally specific barriers beyond language to successfully increase PA in Latinos and highlight a need for formative research and design of interventions for Latino men.
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Purpose The purpose of this paper is to explore the contribution of global business services to improved productivity and economic growth of the world economy, which has gone largely unnoticed in service research. Design/methodology/approach The authors draw on macroeconomic data and industry reports, and link them to the non-ownership-concept in service research and theories of the firm. Findings Business services explain a large share of the growth of the global service economy. The fast growth of business services coincides with shifts from domestic production towards global outsourcing of services. A new wave of global business services are traded across borders and have emerged as important drivers of growth in the world’s service sector. Research limitations/implications This paper advances the understanding of non-ownership services in an increasingly global and specialized post-industrial economy. The paper makes a conceptual contribution supported by descriptive data, but without empirical testing. Originality/value The authors integrate the non-ownership concept and three related economic theories of the firm to explain the role of global business services in driving business performance and the international transformation of service economies.
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The direct and indirect health effects of increasingly warmer temperatures are likely to further burden the already overcrowded hospital emergency departments (EDs). Using current trends and estimates in conjunction with future population growth and climate change scenarios, we show that the increased number of hot days in the future can have a considerable impact on EDs, adding to their workload and costs. The excess number of visits in 2030 is projected to range between 98–336 and 42–127 for younger and older groups, respectively. The excess costs in 2012–13 prices are estimated to range between AU$51,000–184,000 (0–64) and AU$27,000–84,000 (65+). By 2060, these estimates will increase to 229–2300 and 145–1188 at a cost of between AU$120,000–1,200,000 and AU$96,000–786,000 for the respective age groups. Improvements in climate change mitigation and adaptation measures are likely to generate synergistic health co-benefits and reduce the impact on frontline health services.
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Glutamine is conditionally essential in cancer cells, being utilized as a carbon and nitrogen source for macromolecule production, as well as for anaplerotic reactions fuelling the tricarboxylic acid (TCA) cycle. In this study, we demonstrated that the glutamine transporter ASCT2 (SLC1A5) is highly expressed in prostate cancer patient samples. Using LNCaP and PC-3 prostate cancer cell lines, we showed that chemical or shRNA-mediated inhibition of ASCT2 function in vitro decreases glutamine uptake, cell cycle progression through E2F transcription factors, mTORC1 pathway activation and cell growth. Chemical inhibition also reduces basal oxygen consumption and fatty acid synthesis, showing that downstream metabolic function is reliant on ASCT2-mediated glutamine uptake. Furthermore, shRNA knockdown of ASCT2 in PC-3 cell xenografts significantly inhibits tumour growth and metastasis in vivo, associated with the down-regulation of E2F cell cycle pathway proteins. In conclusion, ASCT2-mediated glutamine uptake is essential for multiple pathways regulating the cell cycle and cell growth, and is therefore a putative therapeutic target in prostate cancer.
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This project is a step towards assessing the effects of climate change on the tra catfish industry in Vietnam. The methods were designed to evaluate possible effects of salinity and temperature increase and their interaction on fish physiological parameters, growth performance, survival and the expression of stress related genes. Results indicated that tra had higher overall performance at 35oC with 6ppt salinity and therefore should cope with moderate predicted outcomes of climate change for the region. The experiments were mostly conducted in the Mekong Delta, Vietnam - the centre of the tra catfish industry with the cooperation of Can Tho University – Can Tho City – Vietnam.
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Sputtering and subsequent sulfurization(orselenization)is one of the methods that have been extensively employed to fabricate Cu2ZnSn(S,Se)4 (CZTSSe) thin films. However, there are limited reports on the effect of precursor stacking order of the sputtered source materials on the properties of the synthesized CZTSSe films. In this work,the morphology and crystallization process of the CZTSSe films which were prepared by selenizing Cu–ZnS–SnS precursor layers with different stacking sequences and the adhesion property between the as-synthesized CZTSSe layer and Mosubstrate have been thoroughly investigated. It has been found that the growth of CZTSSe material and the morphology of the film strongly depend on the location of Culayer in the precursor film. The formation of CZTSSe starts from the diffusion of Cu–Se to Sn(S,Se)layert o form Cu–Sn–(S,Se) compound,followed by the reaction with Zn(S,Se). The investigation of themorphology of the CZTSSe films has shown that large grains are formed in the film with the precursor stacking order of Mo/SnS/ZnS/Cu,which is attributed to a bottom-to-top growth mechanism. In contrast, the film made from a precursor with a stacking sequence of Mo/ZnS/ SnS/Cu is mainly consisted of small grains due to a top-to-bottom growth mechanism. The best CZTSSe solar cell with energy conversion efficiency of3.35%has been achieved with the selenized Mo/ZnS/ SnS/Cu film, which is attributed to a good contact between the absorber layer and the Mosubstrate.
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Organic solvents are commonly used in ink precursors of Cu2ZnSnS4 (CZTS) nanocrystals to make thin films for applications such as solar cells. However, the traces of carbon residual left behind by the organic solvents after high-temperature annealing is generally considered to restrict the growth of nanocrystals to form large grains. This work reported the first systematic study on the influence of carbon content of organic solvents on the grain growth of CZTS nanomaterial during high temperature sulfurization annealing. Solvents with carbon atom per molecule varying from 3 to 10 were used to made ink of CZTS nanocrystals for thin film deposition. It has been found that, after high temperature sulfurization annealing, a bilayer structure was formed in the CZTS film using organic solvent containing 3 carbon atoms per solvent molecule based on glycerol and 1,3-propanediol. The top layer consisted of closelypacked large grains and the bottom layer was made of as-synthesized nanoparticles. In contrast, the CZTS film made with the solvent molecule with more carbon atoms including 1,5-pentanediol (5 carbon atoms) and 1,7-heptanediol (7 carbon atoms) consisted of nanoparticles embedded with large crystals. It is believed that the carbon residues left behind by the organic solvents affected the necking of CZTS nanocrystals to form large grains through influencing the surface property of nanocrystals. Furthermore, it has also been observed that the solvent affected the thickness of MoS2 layer which was formed between CZTS and Mo substrate. A thinner MoS2 film (50 nm) was obtained with the slurry using carbon-rich terpineol as solvent whereas the thickest MoS2 (350 nm) was obtained with the film made from 1,3-propanediol based solvent. The evaluation of the photoactivity of the CZTS thin films has demonstrated that a higher photocurrent was generated with the film containing more large grains.
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The construction industry has long been considered to have unacceptably high injury and fatality rates. Previous research has shown that small construction companies sustain higher injury rates than large companies. However, despite the industry being dominated by a very large number of such small companies, little is known of their occupational health and safety (OHS) needs, practices and constraints. This paper takes a first step in aiming to identify the principal barriers that affect good OHS performance of small construction companies so that effective OHS practices can be developed to improve this in future. The contents of the literature are first summarised, in which three critical barriers to good OHS practice in small construction firms are proposed. They are : cost, time, lack of safety awareness and concern. The results of a questionnaire survey carried out with South East Queensland construction personnel are presented, which largely confirm what is suggested by the literature research and also succeed in providing an indication of their ranking in terms of importance and suggestions for overcoming these barriers. The research results provide a better understanding of the issues that restrict good OHS practice in small construction companies and potential measures for improvement.
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This series of research vignettes is aimed at sharing current and interesting research findings from our team of international Entrepreneurship researchers. This vignette is written by Professor Erkko Autio at Imperial College (UK) with some editing by the Director of ACE, Professor Per Davidsson.
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A candidate gene approach using type I single nucleotide polymorphism (SNP) markers can provide an effective method for detecting genes and gene regions that underlie phenotypic variation in adaptively significant traits. In the absence of available genomic data resources, transcriptomes were recently generated in Macrobrachium rosenbergii to identify candidate genes and markers potentially associated with growth. The characterisation of 47 candidate loci by ABI re-sequencing of four cultured and eight wild samples revealed 342 putative SNPs. Among these, 28 SNPs were selected in 23 growth-related candidate genes to genotype in 200 animals selected for improved growth performance in an experimental GFP culture line in Vietnam. The associations between SNP markers and individual growth performance were then examined. For additive and dominant effects, a total of three exonic SNPs in glycogen phosphorylase (additive), heat shock protein 90 (additive and dominant) and peroxidasin (additive), and a total of six intronic SNPs in ankyrin repeats-like protein (additive and dominant), rolling pebbles (dominant), transforming growth factor-β induced precursor (dominant), and UTP-glucose-1-phosphate uridylyltransferase 2 (dominant) genes showed significant associations with the estimated breeding values in the experimental animals (P =0.001−0.031). Individually, they explained 2.6−4.8 % of the genetic variance (R2=0.026−0.048). This is the first large set of SNP markers reported for M. rosenbergii and will be useful for confirmation of associations in other samples or culture lines as well as having applications in marker-assisted selection in future breeding programs.
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In this chapter, the authors define community resilience and identify the components that predict it will occur. Three dimensions are highlighted: recovery, sustainability, and growth. Their discussion focuses on communities like those of Sudanese refugees who have experienced forced migration, emphasizing the importance that community plays to future adaptation. They show through their report on their research that community collaboration, shared identity, and empowerment increase bonding and bridging capital that promote the well-being of people under stress. They argue that an emphasis on community resilience places value on the social connections, policies, programs, and community context necessary for resilience in different cultures and contexts.
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Background Miscommunication in the healthcare sector can be life-threatening. The rising number of migrant patients and foreign-trained staff means that communication errors between a healthcare practitioner and patient when one or both are speaking a second language are increasingly likely. However, there is limited research that addresses this issue systematically. This protocol outlines a hospital-based study examining interactions between healthcare practitioners and their patients who either share or do not share a first language. Of particular interest are the nature and efficacy of communication in language-discordant conversations, and the degree to which risk is communicated. Our aim is to understand language barriers and miscommunication that may occur in healthcare settings between patients and healthcare practitioners, especially where at least one of the speakers is using a second (weaker) language. Methods/Design Eighty individual interactions between patients and practitioners who speak either English or Chinese (Mandarin or Cantonese) as their first language will be video recorded in a range of in- and out-patient departments at three hospitals in the Metro South area of Brisbane, Australia. All participants will complete a language background questionnaire. Patients will also complete a short survey rating the effectiveness of the interaction. Recordings will be transcribed and submitted to both quantitative and qualitative analyses to determine elements of the language used that might be particularly problematic and the extent to which language concordance and discordance impacts on the quality of the patient-practitioner consultation. Discussion Understanding the role that language plays in creating barriers to healthcare is critical for healthcare systems that are experiencing an increasing range of culturally and linguistically diverse populations both amongst patients and practitioners. The data resulting from this study will inform policy and practical solutions for communication training, provide an agenda for future research, and extend theory in health communication.
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High conductive graphene films can be grown on metal foils by chemical vapor deposition (CVD). We here analyzed the use of ethanol, an economic precursor, which results also safer than commonly-used methane. A comprehensive range of process parameters were explored in order to obtain graphene films with optimal characteristics in view of their use in optoelectronics and photovoltaics. Commercially-available and electro-polished copper foils were used as substrates. By finely tuning the CVD conditions, we obtained few-layer (2-4) graphene films with good conductivity (-500 Ohm/sq) and optical transmittance around 92-94% at 550 nm on unpolished copper foils. The growth on electro-polished copper provides instead predominantly mono-layer films with lower conductivity (>1000 Ohm/sq) and with a transmittance of 97.4% at 550 nm. As for the device properties, graphene with optimal properties as transparent conductive film were produced by CVD on standard copper with specific process conditions.