59 resultados para Ager


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The objective biomization method developed by Prentice et al. (1996) for Europe was extended using modern pollen samples from Beringia and then applied to fossil pollen data to reconstruct palaeovegetation patterns at 6000 and 18,000 14C yr bp. The predicted modern distribution of tundra, taiga and cool conifer forests in Alaska and north-western Canada generally corresponds well to actual vegetation patterns, although sites in regions characterized today by a mosaic of forest and tundra vegetation tend to be preferentially assigned to tundra. Siberian larch forests are delimited less well, probably due to the extreme under-representation of Larix in pollen spectra. The biome distribution across Beringia at 6000 14C yr bp was broadly similar to today, with little change in the northern forest limit, except for a possible northward advance in the Mackenzie delta region. The western forest limit in Alaska was probably east of its modern position. At 18,000 14C yr bp the whole of Beringia was covered by tundra. However, the importance of the various plant functional types varied from site to site, supporting the idea that the vegetation cover was a mosaic of different tundra types.

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BIOME 6000 is an international project to map vegetation globally at mid-Holocene (6000 14C yr bp) and last glacial maximum (LGM, 18,000 14C yr bp), with a view to evaluating coupled climate-biosphere model results. Primary palaeoecological data are assigned to biomes using an explicit algorithm based on plant functional types. This paper introduces the second Special Feature on BIOME 6000. Site-based global biome maps are shown with data from North America, Eurasia (except South and Southeast Asia) and Africa at both time periods. A map based on surface samples shows the method’s skill in reconstructing present-day biomes. Cold and dry conditions at LGM favoured extensive tundra and steppe. These biomes intergraded in northern Eurasia. Northern hemisphere forest biomes were displaced southward. Boreal evergreen forests (taiga) and temperate deciduous forests were fragmented, while European and East Asian steppes were greatly extended. Tropical moist forests (i.e. tropical rain forest and tropical seasonal forest) in Africa were reduced. In south-western North America, desert and steppe were replaced by open conifer woodland, opposite to the general arid trend but consistent with modelled southward displacement of the jet stream. The Arctic forest limit was shifted slighly north at 6000 14C yr bp in some sectors, but not in all. Northern temperate forest zones were generally shifted greater distances north. Warmer winters as well as summers in several regions are required to explain these shifts. Temperate deciduous forests in Europe were greatly extended, into the Mediterranean region as well as to the north. Steppe encroached on forest biomes in interior North America, but not in central Asia. Enhanced monsoons extended forest biomes in China inland and Sahelian vegetation into the Sahara while the African tropical rain forest was also reduced, consistent with a modelled northward shift of the ITCZ and a more seasonal climate in the equatorial zone. Palaeobiome maps show the outcome of separate, independent migrations of plant taxa in response to climate change. The average composition of biomes at LGM was often markedly different from today. Refugia for the temperate deciduous and tropical rain forest biomes may have existed offshore at LGM, but their characteristic taxa also persisted as components of other biomes. Examples include temperate deciduous trees that survived in cool mixed forest in eastern Europe, and tropical evergreen trees that survived in tropical seasonal forest in Africa. The sequence of biome shifts during a glacial-interglacial cycle may help account for some disjunct distributions of plant taxa. For example, the now-arid Saharan mountains may have linked Mediterranean and African tropical montane floras during enhanced monsoon regimes. Major changes in physical land-surface conditions, shown by the palaeobiome data, have implications for the global climate. The data can be used directly to evaluate the output of coupled atmosphere-biosphere models. The data could also be objectively generalized to yield realistic gridded land-surface maps, for use in sensitivity experiments with atmospheric models. Recent analyses of vegetation-climate feedbacks have focused on the hypothesized positive feedback effects of climate-induced vegetation changes in the Sahara/Sahel region and the Arctic during the mid-Holocene. However, a far wider spectrum of interactions potentially exists and could be investigated, using these data, both for 6000 14C yr bp and for the LGM.

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Networks and cooperatives have become very common in the woodworking industry during the1990’s. As part of a research project on small enterprise development in the woodworking industry within the Target 6 area (in Sweden) of the European Community, this study follows the development of a dozen cooperative projects during the period 1997-2000. In order to broaden the knowledge base of the study, in 1998 we carried out a survey of cooperative ventures in the woodworking industry in the rest of the country, and collected information about their history, present situation and future strategy. Together with our own material we achieved a body of material consisting of some 30 cases which were subjected to exploratory analysis. We identified the following categories of projects and cooperative ventures; ”Local development projects”, ”Development networks”, ”Producer networks” and ”Development supporting networks”. Most of the producer networks were horizontally integrated but some of them were vertically integrated, along the processing chain from the forest to the customer. Nearly all the local development projects and the networks had been initiated within the last four years. It is, therefore, too early to make any conclusions about their success. Our main finding, so far, is that local development and the establishment of networks requires ”driving forces” in the form of committed individuals, time, money and project organisation. Most of the projects and networks were supported by public funds.

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The objective of this study has been to describe and analyse existing forms of organisation in heating plants using wood fuels, regarding work tasks, organisational structure, skill demands, crew recruitment, working hours and wage conditions. Sixteen plants ranging from 10 to 120 MW have been studied by means of interviews, work place observations and written material. The job of the operator of heating plants is fairly qualified, independent and varied. The most negative factor is shift work. Some of the bigger plants (enterprises) have a relatively hierarchic, segmented and perhaps also an oversized organisation. However, modern concepts of organisation, such as customer orientation, ”flat organisation”, integration of production and maintenance etc, are gaining ground. Blue collar and white collar tasks are increasingly being integrated. Some of the medium sized enterprises have reached very far and may serve as models for bigger enterprises.

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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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PurposeSelective Estrogen Receptor Modulators (SERMs) reduce the risk of breast cancer for women at increased risk by 38%. However, uptake is extremely low and the reasons for this are not completely understood. The aims of this study were to utilize time trade-off methods to determine the degree of risk reduction required to make taking SERMs worthwhile to women, and the factors associated with requiring greater risk reduction to take SERMs. MethodsWomen at increased risk of breast cancer (N = 107) were recruited from two familial cancer clinics in Australia. Participants completed a questionnaire either online or in pen and paper format. Hierarchical multiple linear regression analysis was used to analyze the data. ResultsOverall, there was considerable heterogeneity in the degree of risk reduction required to make taking SERMs worthwhile. Women with higher perceived breast cancer risk and those with stronger intentions to undergo (or who had undergone) an oophorectomy required a smaller degree of risk reduction to consider taking SERMs worthwhile. ConclusionWomen at increased familial risk appear motivated to consider SERMs for prevention. A tailored approach to communicating about medical prevention is essential. Health professionals could usefully highlight the absolute (rather than relative) probability of side effects and take into account an individual’s perceived (rather than objective) risk of breast cancer.

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Os desafios advindos da redefinição do papel do Estado e da busca pela eficiência na prestação dos serviços públicos fundamentam a realização do presente estudo. Diante disso, abordou-se a realidade dos Gerentes das Agencias da Previdência Social do Instituto Nacional do Seguro Social, pessoas-chave na implantação de um modelo de Administração Pública que atenda às demandas sociais. Buscou-se identificar as percepções sobre o desenvolvimento da liderança, explicitando as relações de gênero vivenciadas no exercício desses cargos. A abordagem de gênero baseou-se no expressivo contingente de mulheres existente no serviço público. Assim, entende-se que as questões de liderança nesse setor são permeadas pelas relações de gênero. Nesse aspecto, foi realizada a contextualização da trajetória e lutas das mulheres por emancipação e da situação delas nos cargos de destaque na Administração Pública. Contextualizando o presente estudo, realizou-se a construção histórica e a apresentação dos conceitos relacionados à modernização do Estado, à Gestão Pública e à prestação dos serviços públicos no Brasil, isso conduziu à discussão de temas relacionados à cidadania e direitos sociais. Quanto aos aspectos metodológicos, trata-se de um estudo de caso, com abordagem qualitativa, de caráter descritivo. A pesquisa de campo viabilizou os meios para a coleta dos dados, com a aplicação de questionário e entrevista semiestrurada associada à construção de desenhos. Adotou-se a análise de conteúdo para o tratamento dos dados. Foi realizada a caracterização do perfil sócio-profissional dos servidores que ocupam cargos de gerente no nível operacional do INSS e abordados os dilemas decorrentes do exercício de cargos de chefia e da busca pela liderança no desenvolvimento das competências necessárias à gestão das Agências. No âmbito das relações de gênero, foram correlacionados os significados, a partir da elaboração das vivências, enquanto homens e mulheres, no desempenho do papel de gerente nesses locais de trabalho. Importantes resultados foram observados na análise das entrevistas com a aplicação da técnica de construção de desenhos. Em geral, os gerentes demonstraram gostar e ter orgulho do que fazem, contudo, há desgastes e tensionamentos decorrentes das deficiências de infraestrutura, entre outras. Apesar disso, os gerentes demonstram capacidade de aprendizagem com essas situações e sobressaem muitos sentimentos positivos, entre eles, envolvimento, compromisso e colaboração. Os resultados da pesquisa levantam questões e recomendações que serão colocadas à disposição da organização, com elementos e reflexões no intuito de contribuir com os processos educacionais na gestão de pessoas.

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La mia sperimentazione si inserisce in un progetto di respiro nazionale- “AGER-STAY FRESH”- volto a trovare soluzioni di lavaggio alternative al cloro per il prolungamento della shelf-life delle produzioni di IV gamma. Questi prodotti rappresentano, attualmente, uno dei più promettenti ed innovativi comparti del settore ortofrutticolo e sono definiti, secondo le norme della Comunità Europea, prodotti minimamente trasformati, cioè soggetti a interventi tecnologici ridotti, ed utilizzabili per il consumo diretto senza ulteriori manipolazioni, o con manipolazioni minime. La loro espansione sul mercato deriva dal fatto che sono in grado di offrire alta convenienza, alto valore nutrizionale ed organolettico e sono concepiti dai consumatori come prodotti “genuini” in quanto a base vegetale e, generalmente, non contengono sostanze antimicrobiche. Tuttavia, le materie prime vegetali utilizzate per le produzioni di IV gamma sono spesso caratterizzate da elevate contaminazioni microbiche (4-6 log UFC/g) poiché, durante la crescita o il post-raccolta, frutti o vegetali vengono a contatto con il suolo, insetti o contaminazioni di origine umana.Al momento la shelf-life e la sicurezza d’uso di questa categoria di prodotti sono basate principalmente sul mantenimento della catena del freddo unitamente alla fase di lavaggio delle materie prime con sostanze clorate. Recentemente, però, alcuni autori hanno evidenziato alcuni svantaggi derivanti da questa fase di processo come la formazione di composti clorati cancerogeni. In questa prospettiva, il principale obiettivo di questo lavoro di tesi è stato quello di valutare gli effetti di olio essenziale di cedro e alcuni composti bioattivi degli oli essenziali (citrale, esanale, trans-2-esenale e carvacrolo), utilizzati singolarmente o in combinazione, sulla shelf-life di mele affettate di IV gamma. Su tutti i prodotti sono state eseguite analisi microbiologiche, di texture e colore. Un ulteriore obiettivo di questo lavoro sperimentale è stato quello di ottimizzare alcuni parametri di processo come la riduzione del rapporto acqua di lavaggio/prodotto ed incrementare la temperatura dell’acqua utilizzata al fine di meglio solubilizzare gli antimicrobici in fase di dipping.

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The fatty acid synthesis type II pathway has received considerable interest as a candidate therapeutic target in Plasmodium falciparum asexual blood-stage infections. This apicoplast-resident pathway, distinct from the mammalian type I process, includes FabI. Here, we report synthetic chemistry and transfection studies concluding that Plasmodium FabI is not the target of the antimalarial activity of triclosan, an inhibitor of bacterial FabI. Disruption of fabI in P. falciparum or the rodent parasite P. berghei does not impede blood-stage growth. In contrast, mosquito-derived, FabI-deficient P. berghei sporozoites are markedly less infective for mice and typically fail to complete liver-stage development in vitro. This defect is characterized by an inability to form intrahepatic merosomes that normally initiate blood-stage infections. These data illuminate key differences between liver- and blood-stage parasites in their requirements for host versus de novo synthesized fatty acids, and create new prospects for stage-specific antimalarial interventions.