911 resultados para Determining factors


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Background Sub-microscopic (SM) Plasmodium infections represent transmission reservoirs that could jeopardise malaria elimination goals. A better understanding of the epidemiology of these infections and factors contributing to their occurrence will inform effective elimination strategies. While the epidemiology of SM P. falciparum infections has been documented, that of SM P. vivax infections has not been summarised. The objective of this study is to address this deficiency. Methodology/Principal Findings A systematic search of PubMed was conducted, and results of both light microscopy (LM) and polymerase chain reaction (PCR)-based diagnostic tests for P. vivax from 44 cross-sectional surveys or screening studies of clinical malaria suspects were analysed. Analysis revealed that SM P. vivax is prevalent across different geographic areas with varying transmission intensities. On average, the prevalence of SM P. vivax in cross-sectional surveys was 10.9%, constituting 67.0% of all P. vivax infections detected by PCR. The relative proportion of SM P. vivax is significantly higher than that of the sympatric P. falciparum in these settings. A positive relationship exists between PCR and LM P. vivax prevalence, while there is a negative relationship between the proportion of SM P. vivax and the LM prevalence for P. vivax. Amongst clinical malaria suspects, however, SM P. vivax was not identified. Conclusions/Significance SM P. vivax is prevalent across different geographic areas, particularly areas with relatively low transmission intensity. Diagnostic tools with sensitivity greater than that of LM are required for detecting these infection reservoirs. In contrast, SM P. vivax is not prevalent in clinical malaria suspects, supporting the recommended use of quality LM and rapid diagnostic tests in clinical case management. These findings enable malaria control and elimination programs to estimate the prevalence and proportion of SM P. vivax infections in their settings, and develop appropriate elimination strategies to tackle SM P. vivax to interrupt transmission.

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Cooperatives have a long historical experience in the Spanish economy and have demonstrated their ability to compete against traditional firms in the market. To maintain this capability, while taking advantage of the competitive advantages associated with their idiosyncrasies as social economy enterprises, they should take into consideration that the economy is increasingly globalized and increasingly knowledge-based, especially with regards to technological content. As a consequence, the innovative capacity appears to be a key aspect in order to be able to challenge competitors. This article characterizes the innovative behavior of cooperatives in the region of Castile and Leon and analyses the internal and external factors affecting their innovative performance, based on data from a survey of 581 cooperatives. The results of the empirical analysis, which is performed by multivariate binary logistic regression on various types of innovation, lead us to identify the size of the organizations, the existence of planning, the R & D activities and the human capital as the main determining factors.

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This thesis considers the factors involved in the determination of egg quality and fecundity in farmed stocks of rainbow trout ( Salmo gairdneri R) • Measurements of egg quality, ie. percentage survivals of eggs and fry, from the production batches of eggs of seven fish farms, showed mean survivals of 70% to eying but levels of only 35% to 4.5g fry (approx. 130 days post-fertilisation). Under optimum conditions survivals may reach 85% suggesting that husbandry methods exert significant influences on egg quality. Chemical analyses of the protein, fat, vitellogenin, ash, amino acids, free fatty acid and mineral levels of eggs of varying quality and from parents of different strains showed compositional differences even between individuals of the same stock. However, none of these differences were correlated with egg quality. Egg size showed similar variations but, again under hatchery conditions there was no correlation with differences in egg quality. The only factor which has been shown to exert a significant influence on egg quality is the time of stripping after ovulation. At 1 0°C eggs should be removed from gravid females within ten days of ovulation to achieve optimum egg and fry survival. Studies of egg production from approximately 10,000 broodstock revealed that total fecundity and egg size increased and relative fecundity decreased with increasing fish size. In general, most fish appeared to produce a constant volume of eggs. This is consistent with a hypothesis that egg size can only be increased by parallel reductions in fecundity. Feeding broodstock at half-ration (0.35% body weight day- 1 ) did not affect egg quality but reduced total fecundity and egg size and increased relative fecundity when compared with eggs produced by fish on full-ration. Comparisons of regressions of total fecundity against fish weight for three strains using ANOCO revealed that one strain was significantly more fecund than two other strains considered. Trout of the same strain maintained on different farms behaved similarly suggesting there was some reproducibility of strain characteristics.

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A szerző kutatásában azt vizsgálja, hogy az értékesítés területén dolgozó munkatársak piaci megfigyeléseit milyen mértékben képesek beépíteni a marketingvezetők a menedzsmentmunkába. Az értékesítési munkatársak piaci megfigyelései mindig naprakészek, ráadásul jelentősebb ráfordítás nélkül hozzáférhetők. A marketing- és a sales munkatársak közötti hagyományosan konfliktusokkal terhelt kapcsolat miatt azonban a vállalatok sokszor mégsem aknázzák ki a piaci tájékozódásnak ezt a lehetőségét. A nagyvállalati mintán empirikusan tesztelt modell szerint a menedzserek azon képessége, hogy felhasználják a vállalaton belül rendelkezésre álló információkat, alapvetően nem egyéni, hanem szervezeti képesség. Azok a menedzserek, akik olyan cégeknél dolgoznak, ahol a vállalati továbbképzések során más részlegek munkájába is bekapcsolódhatnak, nagyobb mértékben támaszkodnak a munkatársak piaci megfigyeléseire döntéseik meghozatala során. _____ The author examines in her research that to what extent marketing leaders can build market experience of sales employees into the management activity. Because of the traditionally problematic relationship between marketing and sales employees, companies do not exploit this opportunity of market orientation. According to the model tested on a big corporation sample, the capacity of managers to use information available within the company is basically not an individual but organisational capacity.

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Agricultural development has not yet created empowered farmers in Indonesia. Most farmers living in eastern Indonesia are peasants with low access to development resources. This condition causes most of the peasants to be classified as poor citizens. This research was meant to formulate improvement strategies for empowerment of the peasants. The data were collected between March – May 2012 using the following methods: observation, interview and focus group discussion. The data was analysed using descriptive statistic and structural equation modelling (SEM) and showed that: (1) the empowerment of peasants was within the lowest category for all variables, namely: the peasant characteristics, the role of the agents for development, program quality, the learning process and access to environmental support, (2) the determining factors affecting the empowerment of the peasants were: program implementation quality, the role of the agents of development, environmental access and support, the peasant characteristics, and the appropriateness of the learning process and (3) the strategy to improve empowerment of the peasants could be through corrective efforts towards program implementation quality, the role of facilitators, environmental access and support while considering the peasant characteristics and the learning process of the peasants.

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Monthly samples were taken from April 1992 to March 1993 of fish assemblages present in six permanent lagoons and four ponds, fragmented from them during the drought period and during the terminal phases of desiccation, to evaluate changes in their diversity, abundance and dominance. Their relationships with hydrological and environment conditions were examined. A total of 63 fish species were identified. Species composition and abiotic factors were heterogeneous among the different water bodies. The proportion of piscivores and oxygen concentration were the determining factors for structuring the assemblages. The impact of piscivory upon fish diversity was neutral at the beginning and negative at the end of the dry season. In the terminal phase of desiccation, diversity was higher in ponds that contained a moderate proportion of piscivores than in these containing a higher proportion.

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In this article we aim to analyze the relationship between a set of organizational extrinsic and intrinsic factors and the adoption of the Balanced Scorecard(BSC) by privately-owned Portuguese organizations (large companies and small and médium enterprises).These factos are related to companies age,the diversity of products and services,the nature of the ownership structure,the internationalization,and the organizational size. As a primary means of data collection was carried out a postal survey through a questionnaire sent to 549 privately-owned Portuguese organizations, with na overall responserate of 28.2%. The results indicate that the degree of diversity of the products/services of the organization,the owner- ship of foreign groups,and theo rganizational size are positively associated with the implementation of the BSC.Thus,we conclude that the BSC increases with the degree of diversity of the products/services of the organization,that the Portuguese organizations that use the BSC are mainly owned by foreign groups; and larger organizations are most likely to use this tool.

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A vállalkozóvá válás meghatározó tényezőinek kutatása szakmai berkekben leginkább a Szent Grál keresésére emlékeztet: már lassan azt sem tudjuk, hogy egyáltalán léteznek-e ilyen tényezők. A kutatást nehezítik a többnyire önbevallásos kérdésekre adott torzított válaszok, a szóba jöhető tényezők számossága és a vállalkozói motivációk heterogenitása a különböző demográfiai karakterisztikákkal rendelkező népesség körében. Az egyetemi hallgatók körében némileg egyszerűbb a vizsgálat, hiszen ez egy relatíve homogén minta. Ugyanakkor itt a leginkább áttételesek a hatások, és ráadásul nem a tényleges vállalkozóvá válás, hanem többnyire csak a szándékok tesztelhetők. A vállalkozóvá válás szándékát Bandura társadalmi megismerés-elmélete, Shapero elmozduláselmélete és az Ajzen-féle tervezett magatartás elmélet alapján felállított koncepcionális modell keretén belül vizsgálják és elemzik a szerzők. Arra keresik a választ, hogy az egyes vállalkozói tulajdonságok, az egyetemi környezeti tényezők és a családi háttér hogyan hatnak a vállalkozóvá válásra. A teszteléshez a 21 országra kiterjedő 2011-es GUESSS-felmérésből a magyar egyetemi/ főiskolai hallgatók 5224-es erősségű mintáját használták fel. A multimoniális regressziós vizsgálat eredményei megerősítik, hogy a vállalkozói tulajdonságok és a családban levő vállalkozó megléte mellett a vállalkozói oktatás is pozitívan befolyásolják a vállalkozásindítási szándékot. A klaszterelemzés rámutatott arra, hogy a vállalkozói szándékok, az erre ható tényezők, továbbá a választott szak és más demográfiai tényezők szempontjából a hallgatók meglehetősen heterogének. _______ The search for the determining factors to become an entrepreneur is something like searching for the Holy Grail: After many decades we do not even know if these factors exist or not. The research is difficult because the questionnaires are self esteem, the potential influential factors are numerous, and the motivations do vary across the different cohorts of population. It is easier to conduct a survey amongst university students since this sample is relatively homogenous. At the same times, the determining factors to become an entrepreneur cannot be really tested; the authors can examine mostly the attitudes and the intentions. The conceptual model of entrepreneurial intentions, developed in the paper, based on Bandura, Shaper and Ajzen. The paper is testing eight hypotheses about the influential factors of entrepreneurial intentions such as entrepreneurial traits, the university environment, and the family background. For testing the hypothesis they use a sample of 5224 Hungarian students from the GUESSS 2011 survey. According to the multinomial regression, entrepreneurial intentions are positively influenced by certain entrepreneurial traits, entrepreneur in the family, and entrepreneurship courses at the higher education institutions. The cluster analysis results underline the heterogeneity of the students in terms of entrepreneurial intentions, gender, and the major field of studies

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Mesenchymal stem cells (MSCs) are undifferentiated, multi-potent stem cells with the ability to renew. They can differentiate into many types of terminal cells, such as osteoblasts, chondrocytes, adipocytes, myocytes, and neurons. These cells have been applied in tissue engineering as the main cell type to regenerate new tissues. However, a number of issues remain concerning the use of MSCs, such as cell surface markers, the determining factors responsible for their differentiation to terminal cells, and the mechanisms whereby growth factors stimulate MSCs. In this chapter, we will discuss how proteomic techniques have contributed to our current knowledge and how they can be used to address issues currently facing MSC research. The application of proteomics has led to the identification of a special pattern of cell surface protein expression of MSCs. The technique has also contributed to the study of a regulatory network of MSC differentiation to terminal differentiated cells, including osteocytes, chondrocytes, adipocytes, neurons, cardiomyocytes, hepatocytes, and pancreatic islet cells. It has also helped elucidate mechanisms for growth factor–stimulated differentiation of MSCs. Proteomics can, however, not reveal the accurate role of a special pathway and must therefore be combined with other approaches for this purpose. A new generation of proteomic techniques have recently been developed, which will enable a more comprehensive study of MSCs. Keywords

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Background: Recent clinical studies have demonstrated an emerging subgroup of head and neck cancers that are virally mediated. This disease appears to be a distinct clinical entity with patients presenting younger and with more advanced nodal disease, having lower tobacco and alcohol exposure and highly radiosensitive tumours. This means they are living longer, often with the debilitating functional side effects of treatment. The primary objective of this study was to determine how virally mediated nasopharyngeal and oropharyngeal cancers respond to radiation therapy treatment. The aim was to determine risk categories and corresponding adaptive treatment management strategies to proactively manage these patients. Method/Results: 121 patients with virally mediated, node positive nasopharyngeal or oropharyngeal cancer who received radiotherapy treatment with curative intent between 2005 and 2010 were studied. Relevant patient demographics including age, gender, diagnosis, TNM stage, pre-treatment nodal size and dose delivered was recorded. Each patient’s treatment plan was reviewed to determine if another computed tomography (re-CT) scan was performed and at what time point (dose/fraction) this occurred. The justification for this re-CT was determined using four categories: tumour and/or nodal regression, weight loss, both or other. Patients who underwent a re-CT were further investigated to determine whether a new plan was calculated. If a re-plan was performed, the dosimetric effect was quantified by comparing dose volume histograms of planning target volumes and critical structures from the actual treatment delivered and the original treatment plan. Preliminary results demonstrated that 25/121 (20.7%) patients required a re-CT and that these re-CTs were performed between fractions 20 to 25 of treatment. The justification for these re-CTs consisted of a combination of tumour and/or nodal regression and weight loss. 16/25 (13.2%) patients had a replan calculated. 9 (7.4%) of these replans were implemented clinically due to the resultant dosimetric effect calculated. The data collected from this assessment was statistically analysed to identify the major determining factors for patients to undergo a re-CT and/or replan. Specific factors identified included nodal size and timing of the required intervention (i.e. how when a plan is to be adapted). This data was used to generate specific risk profiles that will form the basis of a biologically guided adaptive treatment management strategy for virally mediated head and neck cancer. Conclusion: Preliminary data indicates that virally mediated head and neck cancers respond significantly during radiation treatment (tumour and/or nodal regression and weight loss). Implications of this response are the potential underdosing or overdosing of tumour and/or surrounding critical structures. This could lead to sub-optimal patient outcomes and compromised quality of life. Consequently, the development of adaptive treatment strategies that improve organ sparing for this patient group is important to ensure delivery of the prescribed dose to the tumour volume whilst minimizing the dose received to surrounding critical structures. This could reduce side effects and improve overall patient quality of life. The risk profiles and associated adaptive treatment approaches developed in this study will be tested prospectively in the clinical setting in Phase 2 of this investigation.

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DNA sequence and structure play a key role in imparting fragility to different regions of the genome. Recent studies have shown that non-B DNA structures play a key role in causing genomic instability, apart from their physiological roles at telomeres and promoters. Structures such as G-quadruplexes, cruciforms, and triplexes have been implicated in making DNA susceptible to breakage, resulting in genomic rearrangements. Hence, techniques that aid in the easy identification of such non-B DNA motifs will prove to be very useful in determining factors responsible for genomic instability. In this study, we provide evidence for the use of primer extension as a sensitive and specific tool to detect such altered DNA structures. We have used the G-quadruplex motif, recently characterized at the BCL2 major breakpoint region as a proof of principle to demonstrate the advantages of the technique. Our results show that pause sites corresponding to the non-B DNA are specific, since they are absent when the G-quadruplex motif is mutated and their positions change in tandem with that of the primers. The efficiency of primer extension pause sites varied according to the concentration of monovalant cations tested, which support G-quadruplex formation. Overall, our results demonstrate that primer extension is a strong in vitro tool to detect non-B DNA structures such as G-quadruplex on a plasmid DNA, which can be further adapted to identify non-B DNA structures, even at the genomic level.

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31 p.

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Essa dissertação tem por objetivo compreender como, numa sociedade marcada pela desigualdade, jovens pobres experimentam a condição juvenil. Para tanto se caracterizou a situação familiar, a experiência escolar e laboral bem como, as práticas de sociabilidade dos jovens egressos selecionados do Projovem Urbano, procurando perceber em que medida a participação num Programa voltado para jovens pobres contribuiu para criação de estratégias que viabilizem os projetos de futuro desses jovens. Partimos do pressuposto que Juventude é uma categoria construída socialmente, não podendo ser compreendida de forma monolítica e objetivamente dada. Condição social, etnia, gênero, origem regional, territorial, bem como a fase da vida, influenciam na forma de experimentar a condição juvenil. Pela natureza das questões, optou-se por uma abordagem qualitativa associando revisão bibliográfica e pesquisa de campo onde as realizações de entrevistas aprofundadas semi - estruturadas e a análise de documentos relacionados ao tema constituíram os elementos centrais do campo. Foram realizadas entrevistas aprofundadas com 14 jovens, concluintes do Projovem Urbano (2008-2010), na cidade do Rio de Janeiro, de ambos os sexos (8 mulheres e 6 homens) e com idade entre 20 e 30 anos, agrupados em faixa etária ( 20 a 25 anos e 26 a 30 anos). Ao final desse estudo nos foi possível entender que o acesso desigual às oportunidades para se vivenciar esse período, reduzem as possibilidades de experimentação da condição juvenil.

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As cianobactérias Microcystis aeruginosa e Planktothrix agardhii são espécies formadoras de florações comuns em ecossistemas aquáticos eutrofizados. Nestes ambientes, a disponibilidade de luz é um dos fatores determinantes para o desenvolvimento e estruturação da comunidade fitoplanctônica. O presente estudo teve como objetivo investigar o efeito da luz na fisiologia de cepas de cianobactérias (M. aeruginosa e P. agardhii), avaliando o crescimento, a variabilidade inter e intra-específica e a competição por luz. Para tanto foram realizados cultivos estanques em diferentes intensidades luminosas (10, 40, 60, 100 e 500 mol m-2 s-1) e calculadas as taxas de crescimento e os rendimentos máximos das culturas. O requerimento mínimo de luz de cada cepa foi determinado em experimentos com monoculturas em sistemas de cultivo contínuo (quimiostatos) sob condições de limitação de luz. A competição por luz foi avaliada através de experimentos com biculturas em quimiostatos. Foi observada variabilidade intra e inter-específica das cepas, nas diferentes intensidades luminosas testadas. Em 500 μmol m-2 s-1, as cepas de M. aeruginosa obtiveram maior biomassa do que P. agardhii, corroborando a maior sensibilidade de P. agardhii luz. Embora com rendimento máximo menor, P. agardhii cresceu em intensidades luminosas consideradas elevadas para a espécie, 100 e 500 μmol m-2 s-1. Estes resultados evidenciam a capacidade de P. agardhii ocorrer em ambientes com grandes amplitudes de luminosidade. Na intensidade de 10 μmol m-2 s-1, M. aeruginosa e P. agardhii apresentaram crescimento semelhante, demonstrando a habilidade das duas espécies em crescer com pouca luz. Nas monoculturas em quimiostato, sob condições de limitação de luz, as cepas de M. aeruginosa atingiram maior biomassa durante o equilíbrio (steady-state) do que P. agadhii, refletindo uma capacidade suporte mais elevada, enquanto que os valores de requerimento mínimo de luz foram semelhantes entre as duas espécies. Ao competirem, M. aeruginosa superou P. agardhii imediatamente após o início do experimento. Esse rápido crescimento resultou na dominância de M. aeruginosa em todos os pares de cepas testados e, em dois casos, ocorreu exclusão competitiva de P. agardhii. Quando não ocorreu exclusão, P. agardhii conseguiu manter-se no sistema com uma baixa biomassa (ca.15%). Estes resultados ajudam a entender a co-ocorrência destas espécies no ambiente e a dominância de M. aeruginosa mesmo em condições de baixa luminosidade.