701 resultados para 941
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Background: The characterization of phytoestrogen intake and cancer risk has been hindered by the absence of accurate dietary phytoestrogen values. Objective: We examined the risk of breast, colorectal, and prostate cancers relative to phytoestrogen intake on the basis of a comprehensive database. Design: Demographic and anthropometric characteristics, a medical history, and 7-d records of diet were collected prospectively from participants (aged 40–79 y) in the European Prospective Investigation into Cancer and Nutrition–Norfolk (EPIC-Norfolk). Five hundred nine food items were analyzed by liquid chromatography–mass spectrometry/mass spectrometry, and 13C3-labeled internal standards were analyzed for isoflavones (genistein, daidzein, glycitein, biochanin A, and formononetin), lignans (secoisolariciresinol and matairesinol), and enterolignans from gut microbial metabolism in animal food sources (equol and enterolactone). From the direct analysis, values for 10,708 foods were calculated. Odds ratios (ORs) for breast (244 cases, 941 controls), colorectal (221 cases, 886 controls), and prostate (204 cases, 812 controls) cancers were calculated relative to phytoestrogen intake. Results: Phytoestrogen intake was not associated with breast cancer among women or colorectal cancer among men. Among women, colorectal cancer risk was inversely associated with enterolactone (OR: 0.33; 95% CI: 0.14, 0.74) and total enterolignans (OR: 0.32; 95% CI: 0.13, 0.79), with a positive trend detected for secoisolariciresinol (OR: 1.60; 95% CI: 0.96, 2.69). A positive trend between enterolignan intake and prostate cancer risk (OR: 1.27; 95% CI: 0.97, 1.66) was attenuated after adjustment for dairy intake (OR: 1.19; 95% CI: 0.77, 1.82). Conclusion: Dietary phytoestrogens may contribute to the risk of colorectal cancer among women and prostate cancer among men.
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In this paper we draw on the theory of dynamic capabilities to examine development of the only surviving family-owned Liverpool shipping company. The Bibby Line was founded in 1807 to take advantage of the growing sea-trade based in Liverpool. The company remained in shipping until the mid-1960s, when a series of external crises led the owner, Derek Bibby, to begin a process of diversification. In the last 50 years, the Bibby Line has grown into a £1bn business with interests in retail, distribution and financial services as well as a continuing commitment to shipping. Our intention is to demonstrate how multigenerational ownership contributes to the creation of dynamic capabilities in family firms. The distinctive nature of Bibby as a long-standing family business is related to unique assets such as patient capital, flexible governance structures as well as the ability to mobilise social and human capital.
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Activities like the Coupled Model Intercomparison Project (CMIP) have revolutionized climate modelling in terms of our ability to compare models and to process information about climate projections and their uncertainties. The evaluation of models against observations is now considered a key component of multi-model studies. While there are a number of outstanding scientific issues surrounding model evaluation, notably the open question of how to link model performance to future projections, here we highlight a specific but growing problem in model evaluation - that of uncertainties in the observational data that are used to evaluate the models. We highlight the problem using an example obtained from studies of the South Asian Monsoon but we believe the problem is a generic one which arises in many different areas of climate model evaluation and which requires some attention by the community.
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We describe Global Atmosphere 3.0 (GA3.0): a configuration of the Met Office Unified Model (MetUM) developed for use across climate research and weather prediction activities. GA3.0 has been formulated by converging the development paths of the Met Office's weather and climate global atmospheric model components such that wherever possible, atmospheric processes are modelled or parametrized seamlessly across spatial resolutions and timescales. This unified development process will provide the Met Office and its collaborators with regular releases of a configuration that has been evaluated, and can hence be applied, over a variety of modelling régimes. We also describe Global Land 3.0 (GL3.0): a configuration of the JULES community land surface model developed for use with GA3.0.
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Climate change is expected to increase the frequency of some climatic extremes. These may have drastic impacts on biodiversity, particularly if meteorological thresholds are crossed, leading to population collapses. Should this occur repeatedly, populations may be unable to recover, resulting in local extinctions. Comprehensive time series data on butterflies in Great Britain provide a rare opportunity to quantify population responses to both past severe drought and the interaction with habitat area and fragmentation. Here, we combine this knowledge with future projections from multiple climate models, for different Representative Concentration Pathways (RCPs), and for simultaneous modelled responses to different landscape characteristics. Under RCP8.5, which is associated with ‘business as usual’ emissions, widespread drought-sensitive butterfly population extinctions could occur as early as 2050. However, by managing landscapes and particularly reducing habitat fragmentation, the probability of persistence until mid-century improves from around zero to between 6 and 42% (95% confidence interval). Achieving persistence with a greater than 50% chance and right through to 2100 is possible only under both low climate change (RCP2.6) and semi-natural habitat restoration. Our data show that, for these drought-sensitive butterflies, persistence is achieved more effectively by restoring semi-natural landscapes to reduce fragmentation, rather than simply focusing on increasing habitat area, but this will only be successful in combination with substantial emission reductions.
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The first agricultural societies were established around 10 ka BP and had spread across much of Europe and southern Asia by 5.5 ka BP with resultant anthropogenic deforestation for crop and pasture land. Various studies (e.g. Joos et al., 2004; Kaplan et al., 2011; Mitchell et al., 2013) have attempted to assess the biogeochemical implications for Holocene climate in terms of increased carbon dioxide and methane emissions. However, less work has been done to examine the biogeophysical impacts of this early land use change. In this study, global climate model simulations with Hadley Centre Coupled Model version 3 (HadCM3) were used to examine the biogeophysical effects of Holocene land cover change on climate, both globally and regionally, from the early Holocene (8 ka BP) to the early industrial era (1850 CE). Two experiments were performed with alternative descriptions of past vegetation: (i) one in which potential natural vegetation was simulated by Top-down Representation of Interactive Foliage and Flora Including Dynamics (TRIFFID) but without land use changes and (ii) one where the anthropogenic land use model Kaplan and Krumhardt 2010 (KK10; Kaplan et al., 2009, 2011) was used to set the HadCM3 crop regions. Snapshot simulations were run at 1000-year intervals to examine when the first signature of anthropogenic climate change can be detected both regionally, in the areas of land use change, and globally. Results from our model simulations indicate that in regions of early land disturbance such as Europe and south-east Asia detectable temperature changes, outside the normal range of variability, are encountered in the model as early as 7 ka BP in the June–July–August (JJA) season and throughout the entire annual cycle by 2–3 ka BP. Areas outside the regions of land disturbance are also affected, with virtually the whole globe experiencing significant temperature changes (predominantly cooling) by the early industrial period. The global annual mean temperature anomalies found in our single model simulations were −0.22 at 1850 CE, −0.11 at 2 ka BP, and −0.03 °C at 7 ka BP. Regionally, the largest temperature changes were in Europe with anomalies of −0.83 at 1850 CE, −0.58 at 2 ka BP, and −0.24 °C at 7 ka BP. Large-scale precipitation features such as the Indian monsoon, the Intertropical Convergence Zone (ITCZ), and the North Atlantic storm track are also impacted by local land use and remote teleconnections. We investigated how advection by surface winds, mean sea level pressure (MSLP) anomalies, and tropospheric stationary wave train disturbances in the mid- to high latitudes led to remote teleconnections.
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We report an investigation for 16 bacteria and viruses among 184 children hospitalized with pneumonia in Salvador, Brazil. Etiology was established in 144 (78%) cases. Viral, bacterial, and mixed infections were found in 110 (60%), 77 (42%), and 52 (28%) patients, respectively. Rhinovirus (21%) and Streptococcus pneumoniae (21%) were the most common pathogens. Our results demonstrate the importance of viral and pneumococcal infections among those patients.
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Diverse invertebrate and vertebrate species live in association with plants of the large Neotropical family Bromeliaceae. Although previous studies have assumed that debris of associated organisms improves plant nutrition, so far little evidence supports this assumption. In this study we used isotopic ((15)N) and physiological methods to investigate if the treefrog Scinax hayii, which uses the tank epiphytic bromeliad Vriesea bituminosa as a diurnal shelter, contributes to host plant nutrition. In the field, bromeliads with frogs had higher stable N isotopic composition (delta(15)N) values than those without frogs. Similar results were obtained from a controlled greenhouse experiment. Linear mixing models showed that frog feces and dead termites used to simulate insects that eventually fall inside the bromeliad tank contributed, respectively, 27.7% (+/- 0.07 SE) and 49.6% (+/- 0.50 SE) of the total N of V. bituminosa. Net photosynthetic rate was higher in plants that received feces and termites than in controls; however, this effect was only detected in the rainy, but not in the dry season. These results demonstrate for the first time that vertebrates contribute to bromeliad nutrition, and that this benefit is seasonally restricted. Since amphibian-bromeliad associations occur in diverse habitats in South and Central America, this mechanism for deriving nutrients may be important in bromeliad systems throughout the Neotropics.
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We consider real analytic involutive structures V, of co-rank one, defined on a real analytic paracompact orientable manifold M. To each such structure we associate certain connected subsets of M which we call the level sets of V. We prove that analytic regularity propagates along them. With a further assumption on the level sets of V we characterize the global analytic hypoellipticity of a differential operator naturally associated to V. As an application we study a case of tube structures.
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We consider independent edge percolation models on Z, with edge occupation probabilities. We prove that oriented percolation occurs when beta > 1 provided p is chosen sufficiently close to 1, answering a question posed in Newman and Schulman (Commun. Math. Phys. 104: 547, 1986). The proof is based on multi-scale analysis.
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Utgångspunkten i vår undersökning var att grundskolans matematikundervisning sedan länge är präglad av enskild räkning i läroboken och graden av modernisering är låg. Detta grundar vi dels på egen erfarenhet och dels på forskning vi läst tidigare. När elever får problem med matematiken i skolan läggs skulden på eleverna istället för på skolan och lärarens undervisning. Syftet med vårt arbete var att få en bild av vad skolan och den enskilde läraren kan göra för att förändra/förbättra förutsättningarna i matematik för grundskolans elever. Undersökningens frågeställningar var: Vilka faktorer kan ligga bakom elevers utveckling efter ett icke godkänt nationellt prov i matematik i skolår 5? Vad kan skolan och den enskilde läraren göra för att förändra/förbättra förutsättningarna i matematik för grundskolans elever?Vi valde att söka svar på våra frågor dels genom att göra en litteraturstudie och dels genom attintervjua fyra elever som inte blivit godkända på nationella ämnesprovet i matematik i skolår 5. Vi har också intervjuat deras lärare (fem stycken) i skolår 4-6 och skolår 7-9.Utifrån våra resultat kunde vi dra slutsatsen att matematikundervisning inte enbart handlar om bra didaktiska metoder utan snarare om kärlek till och engagemang för eleverna. Våra elever verkar trivas med den kunskapssyn som Lpo 941 vilar på där skolan ska se till varje unik individ och utforma undervisningen därefter. Grundskolans matematikundervisning präglas fortfarande av enskild räkning i läroboken, visade både våra intervjuer och vår litteraturstudie. Detta trots att en enorm mängd forskning talar emot detta ensidiga arbetssätt och istället förespråkar en varieradundervisning. Våra resultat visade också att det extra stöd elever får är undervisning i liten grupp där undervisningen till stor del sker på samma ensidiga sätt. För att lyckas med matematikenmenar elever att lärarens engagemang och tilltro till deras förmåga är den viktigaste faktorn.Andra faktorer som påverkar elevernas resultat är den egna motivationen och lusten att lära.Resultaten visar också att betygen har betydelse för elevernas motivation. Det finnas alltså mycket man kan göra för att förbättra situationen i skolan. De två främsta faktorerna som krävs ärengagerade lärare och en varierad undervisning.
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The objective of this study has been to describe and analyse existing forms of organisation in wood fuel plants regarding work tasks, organisational structure, work content, skill demands, crew recruitment, working hours and wage conditions. The study has been introductory, con¬sisting of 2-3 hour visits to 12 plants.The production of refined wood fuels is carried out in rather small plants. The number of employees ranges from 6 to 15 persons in the factories producing between 20 and 100 thousand tons per year. Generally one shift crew consists of only two persons. The operator job requires multiskill capacity, dexterity and autonomous problem-solving.The job can be considered as qualified, responsible, autonomous, meaningful and variable. It was generally considered that it takes about a year to become a good operator. And even after that, one is still learning. Negative factors are shift work, partly poor physical working environment (dust and noise) and, occasionally, mental pressure and overtime.Modern organisation concepts are, to a large extent, applied in the wood fuel plants. The organisation is flat, lean and customer-oriented.
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We show how to include in the CAPM moments of any order, extending the mean-variance or mean-variance-skewness versions available until now. Then, we present a simple way to modify the formulae, in order to avoid the appearance of utility parameters. The results can be easily applied to practical portfolio design, with econometric inference and testing based on generalised method of moments procedures. An empirical application to the Brazilian stock market is discussed.
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Esse estudo de natureza qualitativa, busca por meio de uma pesquisa exploratória e descritiva analisar se as divulgações nas notas explicativas dos instrumentos financeiros derivativos contabilizados pela metodologia do hedge accounting, efetuados em 2009 pelas empresas brasileiras não financeiras listadas na BM&FBOVESPA atendem a lista de exigências de divulgação do IFRS 7. A relevância desse estudo se deve a dois fatores. O primeiro fator é que a utilização de instrumentos financeiros derivativos tem se tornado cada vez mais comum no mercado mundial e brasileiro, devido a seu grande desenvolvimento e evolução. Apesar de que esses instrumentos, quando utilizados de forma adequada, possam ser excelentes ferramentas para minimizar risco, seu uso descuidado pode levar ao prejuízo e até mesmo à falência de organizações, como foi visto na crise do subprime e outras anteriores. Portanto, a mensuração, evidenciação e controle desses instrumentos tornam-se cada vez mais importantes para que realmente possamos entender o impacto desses instrumentos nos negócios das companhias no curto e no longo prazo. O segundo fator é que com o advento da lei 11.638/07, alterada pela lei 11.941/08, determinou-se que deveremos estar com nossas normas contábeis convergidas para o International Financial Report Standards (IFRS) até o final de 2010. Significa que devemos a partir desse momento seguir os seus pronunciamentos no que se refere a apresentação (IAS 32), reconhecimento e mensuração (IAS 39) e divulgações (IFRS 7) dos instrumentos financeiros. Portanto esse estudo nos permite verificar o quanto as empresas já atendem ou não o IFRS 7.