973 resultados para uncertain polynomials


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De acordo com dados do DATASUS, o setor filantrópico no país possui cerca de 2.100 estabelecimentos hospitalares, com mais de 155.000 leitos, o que representa 31% do total de leitos do país. Ou seja, 1/3 dos leitos existentes no país são filantrópicos, caracterizando o setor como importante prestador de serviços ao Sistema Único de Saúde, assim como à saúde suplementar. Estes números demonstram a importância do setor filantrópico para o país, mas também para muitas regiões, como a região centro sul fluminense do Estado do Rio de Janeiro. A enorme complexidade e diversidade da rede hospitalar filantrópica traz muitos e variados desafios, tanto para a operação hospitalar, como para as políticas governamentais de manutenção do setor saúde. Além da defasagem da tabela do SUS, outros problemas também são enfrentados por estes hospitais como os tetos financeiros, que levam ao pagamento menor do que é efetivamente produzido, atrasos de pagamentos, que dificultam o planejamento e o equilíbrio financeiro, fechamento de linhas de créditos, dificuldades nas negociações com gestores, entre muitos outros. Todas essas dificuldades têm reflexos críticos na gestão dessas organizações que passam por crises financeiras, necessidade de qualificação profissional e de adequações em suas instalações e equipamentos. Esta pesquisa propõe-se a estudar a situação dos hospitais filantrópicos da região Centro-Sul Fluminense do Estado do Rio de Janeiro no âmbito financeiro, assim como conhecer a percepção dos gestores sobre as dificuldades do setor, suas perspectivas e propostas de possíveis soluções. A metodologia utilizada foi de natureza exploratória, com abordagem qualitativa e quantitativa, com estudo de casos múltiplos, utilizando-se de diversas fontes para coleta de dados, como fontes primárias, secundárias e entrevista semi-estruturada. Os resultados demonstraram a importância dos hospitais filantrópicos na produção de serviços de saúde para o SUS e a necessidade da formulação de políticas especificas para a manutenção do setor filantrópico conveniado ao SUS. Na região centro sul fluminense há uma complementaridade entre a rede pública e a rede filantrópica. Embora seja reconhecida a importância histórica e estratégica desses hospitais na prestação de serviços ao SUS, mantidas as condições atuais nos âmbitos de capacidade instalada, organizacional ou financeira, não há dúvidas de que o futuro dessas instituições será incerto com riscos importantes para a continuidade dos serviços prestados e da própria sobrevivência dos hospitais.Existe a necessidade urgente de que os gestores públicos busquem a implantação de modelos flexíveis de gestão, visando o estabelecimento de um relacionamento de parceria com os hospitais filantrópicos e suas ações sejam definidas por metas tangíveis e alcançáveis.

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This is the River Exe Salmon Action Plan Consultation document produced by the Environment Agency in 2003. The report pays attention on the external consultation of the River Exe Salmon Action Plan (SAP). This strategy represents an entirely new approach to salmon management within the UK and introduces the concept of river-specific salmon spawning targets as a salmon management tool. The River Exe SAP follows the format of those completed for the Rivers Teign, Torridge, Taw and Dart. It is the fifth of eight action plans that will be produced for salmon rivers within Devon Area. The River Exe SAP contains a description of the river catchment and highlights particular features that are relevant to the salmon population and the associated fishery. The Exe salmon stock is judged to be meeting its Conservation Limit. However, this assessment is uncertain as it is based on an estimate of rod exploitation rate, which in itself is also uncertain. At present there is no means of accurately assessing the River Exe salmon run. In common with many other rivers, estimation of stock using catch statistics and rod exploitation rate is the model used, when direct assessment is not possible. The installation of a fish counter on the lower river, or the use of other direct counting methods, would help to provide a direct assessment of the annual run of salmon into the river. This would improve our ability to estimate the spawning escapement and hence assess compliance with the Conservation Limit.

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This is the River Lyn Salmon Action Plan Consultation document produced by the Environment Agency in 2003. The report pays attention on the external consultation of the River Lyn Salmon Action Plan (SAP). This approach to salmon management within the England and Wales introduces the concept of river-specific Conservation Limits as a method of assessing the status of the salmon stock. The River Lyn Salmon Action Plan follows the format of those completed for the Rivers Exe, Axe, Avon & Erme, Teign, Torridge, Taw and Dart. It is the last of eight action plans that have been produced for salmon rivers within Devon Area. The River Lyn Salmon Action Plan contains a description of the river catchment and highlights particular features that are relevant to the salmon population and the associated fishery. The Lyn salmon stock is judged to be meeting its Conservation Limit. However, this assessment is uncertain as it is based on an estimate of rod exploitation rate, which in itself is also uncertain.

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A vida impõe decisões às pessoas o tempo todo, e as pessoas as tomam de acordo com seus valores considerando as particularidades de cada situação. Valo-res são quaisquer aspectos da decisão que sejam considerados desejáveis, indese-jáveis, relevantes e importantes como: ser preferido, desejável, agradável, promis-sor, seguro, emocionante, justo, bom, correto, fácil, incerto, etc. Com base nestes valores, entendemos que o fundamento último do utilitarismo é o princípio da maximização da felicidade. Segundo esta concepção, uma ação é considerada correta, logo válida, se ela promover maior felicidade dos implicados. A felicidade é entendida como o alcance do prazer e do bem-estar. Nesta corrente encontramos uma perspectiva eudamonista e hedonista, uma vez que tem em vista como objectivo final a felicidade que consiste no prazer. Qualquer utilitarista tem de se importar, sobretudo com a promoção da felicidade geral. A partir de Mill, a moralidade passa a ser realização de cada ser humano neste mundo, aqui e agora. O princípio de utilidade exige que cada um de nós faça o que for necessário e estiver ao seu alcançe para promover a felicidade e evitar a dor. Ao analisarmos as consequências previsíveis de uma ação, temos que considerar não apenas a quantidade, mas a qualidade de prazer que dela possa resultar. Para os utilitaristas o que importa são as consequências das ações, elas devem visar ao prazer, e somente isso permite avaliar se uma ação é correta ou não, logo é uma perspectiva consequencialista. O que importa são as consequências e não os motivos das nossas ações, desde que isso promova a felicidade ao maior número de pessoas possível. Mas, o ato só é permissível se, e apenas se, maximiza imparcialmente o bem. A filosofia Utilitarista costuma dividir seus leitores. É exaltada por alguns, que defendem o mérito de ser um ponto de vista que oferece melhores subsídios para melhor lidarmos com as questões éticas que realmente importam e estão associadas às condições que tornam possível uma vida feliz e se possível, isenta de sofrimentos. Por outro lado, há aqueles que apontam para o perigo de uma filosofia que estima a qualidade moral de ações levando em consideração apenas as suas consequências. Esta corrente não é uma escola filosófica, uma vez que se trata de uma filosofia que constantemente se reinventa e se adapta a fim de ir sempre ao encontro de novos desafios que uma ética não pode deixar de enfrentar.

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A significant fraction of the total nitrogen entering coastal and estuarine ecosystems along the eastern U.S. coast arises from atmospheric deposition; however, the exact role of atmospherically derived nitrogen in the decline of the health of coastal, estuarine, and inland waters is still uncertain. From the perspective of coastal ecosystem eutrophication, nitrogen compounds from the air, along with nitrogen from sewage, industrial effluent, and fertilizers, become a source of nutrients to the receiving ecosystem. Eutrophication, however, is only one of the detrimental impacts of the emission of nitrogen containing compounds to the atmosphere. Other adverse effects include the production of tropospheric ozone, acid deposition, and decreased visibility (photochemical smog). Assessments of the coastal eutrophication problem indicate that the atmospheric deposition loading is most important in the region extending from Albemarle/Parnlico Sounds to the Gulf of Maine; however, these assessments are based on model outputs supported by a meager amount of actual data. The data shortage is severe. The National Research Council specifically mentions the atmospheric role in its recent publication for the Committee on Environmental and Natural Resources, Priorities for Coastal Ecosystem Science (1994). It states that, "Problems associated with changes in the quantity and quality of inputs to coastal environments from runoff and atmospheric deposition are particularly important [to coastal ecosystem integrity]. These include nutrient loading from agriculture and fossil fuel combustion, habitat losses from eutrophication, widespread contamination by toxic materials, changes in riverborne sediment, and alteration of coastal hydrodynamics. "

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Karenia brevis is the dominant toxic red tide algal species in the Gulf of Mexico. It produces potent neurotoxins (brevetoxins [PbTxs]), which negatively impact human and animal health, local economies, and ecosystem function. Field measurements have shown that cellular brevetoxin contents vary from 1–68 pg/cell but the source of this variability is uncertain. Increases in cellular toxicity caused by nutrient-limitation and inter-strain differences have been observed in many algal species. This study examined the effect of P-limitation of growth rate on cellular toxin concentrations in five Karenia brevis strains from different geographic locations. Phosphorous was selected because of evidence for regional P-limitation of algal growth in the Gulf of Mexico. Depending on the isolate, P-limited cells had 2.3- to 7.3-fold higher PbTx per cell than P-replete cells. The percent of cellular carbon associated with brevetoxins (%C-PbTx) was ~ 0.7 to 2.1% in P-replete cells, but increased to 1.6–5% under P-limitation. Because PbTxs are potent anti-grazing compounds, this increased investment in PbTxs should enhance cellular survival during periods of nutrient-limited growth. The %C-PbTx was inversely related to the specific growth rate in both the nutrient-replete and P-limited cultures of all strains. This inverse relationship is consistent with an evolutionary tradeoff between carbon investment in PbTxs and other grazing defenses, and C investment in growth and reproduction. In aquatic environments where nutrient supply and grazing pressure often vary on different temporal and spatial scales, this tradeoff would be selectively advantageous as it would result in increased net population growth rates. The variation in PbTx/cell values observed in this study can account for the range of values observed in the field, including the highest values, which are not observed under N-limitation. These results suggest P-limitation is an important factor regulating cellular toxicity and adverse impacts during at least some K. brevis blooms.

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Cowcod (Sebastes levis) is a large (100-cm-FL), long-lived (maximum observed age 55 yr) demersal rockfish taken in multispecies commercial and recreational fisheries off southern and central California. It lives at 20–500 m depth: adults (>44 cm TL) inhabit rocky areas at 90–300 m and juveniles inhabit fine sand and clay at 40–100 m. Both sexes have similar growth and maturity. Both sexes recruit to the fishery before reaching full maturity. Based on age and growth data, the natural mortality rate is about M =0.055/yr, but the estimate is uncertain. Biomass, recruitment, and mortality during 1951–98 were estimated in a delay-difference model with catch data and abundance indices. The same model gave less precise estimates for 1916–50 based on catch data and assumptions about virgin biomass and recruitment such as used in stock reduction analysis. Abundance indices, based on rare event data, included a habitat-area–weighted index of recreational catch per unit of fishing effort (CPUE index values were 0.003–0.07 fish per angler hour), a standardized index of proportion of positive tows in CalCOFI ichthyoplankton survey data (binomial errors, 0–13% positive tows/yr), and proportion of positive tows for juveniles in bottom trawl surveys (binomial errors, 0–30% positive tows/yr). Cowcod are overfished in the southern California Bight; biomass during the 1998 season was about 7% of the virgin level and recent catches have been near 20 metric tons (t)/yr. Projections based on recent recruitment levels indicate that biomass will decline at catch levels > 5 t/yr. Trend data indicate that recruitment will be poor in the near future. Recreational fishing effort in deep water has increased and has become more effective for catching cowcod. Areas with relatively high catch rates for cowcod are fewer and are farther offshore. Cowcod die after capture and cannot be released alive. Two areas recently closed to bottom fishing will help rebuild the cowcod stock.

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Teeth of 71 estuarine dolphins (Sotalia guianensis) incidentally caught on the coast of Paraná State, southern Brazil, were used to estimate age. The oldest male and female dolphins were 29 and 30 years, respectively. The mean distance from the neonatal line to the end of the first growth layer group (GLG) was 622.4 ±19.1 μm (n=48). One or two accessory layers were observed between the neonatal line and the end of the first GLG. One of the accessory layers, which was not always present, was located at a mean of 248.9 ±32.6 μm (n=25) from the neonatal line, and its interpretation remains uncertain.The other layer, located at a mean of 419.6 ±44.6 μm (n=54) from the neonatal line, was always present and was first observed between 6.7 and 10.3 months of age. This accessory layer could be a record of weaning in this dolphin. Although no differences in age estimates were observed between teeth sectioned in the anterior-posterior and buccal-lingual planes, we recommend sectioning the teeth in the buccal-lingual plane in order to obtain on-center sections more easily. We also recommend not using teeth from the most anterior part of the mandibles for age estimation. The number of GLGs counted in those teeth was 50% less than the number of GLGs counted in the teeth from the median part of the mandible of the same animal. Although no significant difference (P>0.05) was found between the total lengths of adult male and female estuarine dolphins, we observed that males exhibited a second growth spurt around five years of age. This growth spurt would require that separate growth curves be calculated for the sexes. The asymptotic length (TL∞), k, and t0 obtained by the von Bertalanffy growth model were 177.3 cm, 0.66, and –1.23, respectively, for females and 159.6 cm, 2.02, and –0.38, respectively, for males up to five years, and 186.4 cm, 0.53 and –1.40, respectively, for males older than five years. The total weight (TW)/total length (TL) equations obtained for male and female estuarine dolphins were TW = 3.156 × 10−6 × TL 3.2836 (r=0.96), and TW = 8.974 × 10−5 × TL 2.6182 (r=0.95), respectively.

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Bycatch studies have largely ignored population level effects on fish species of little commercial interest. Here we analyze bycatch of the lined seahorse (Hippocampus erectus) in the bait-shrimp trawl fishery in Hernando Beach, Florida, providing the first fisheries data for this species. Based on catch per unit of effort (CPUE), size, sex, and reproductive status of trawled H. erectus, 1) approximately 72,000 seahorses were caught annually by this fleet, from a population of unknown size, 2) trawling affected population cohorts differentially because of temporal and spatial variation in CPUE and population size, and 3) a greater proportion of females than males was removed in trawling. Our findings suggest that trawling may affect seahorse populations through direct mortality, social disruption, and habitat damage. However, the lack of specific abundance or catchability estimates for H. erectus means that the precise impact of trawling on this fish remains uncertain. This paper focuses attention on the need for research and monitoring of small fishes that are caught incidentally in nonselective gear.

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Along the west coast of the United States, the potential impact of increasing pinniped populations on declining salmonid (Oncorhynchus spp.) stocks has become an issue of concern. Fisheries managers need species-specific estimates of consumption by pinnipeds to evaluate their impact on salmonid stocks. To estimate consumption, we developed a model that estimates diet composition by reconstructing prey biomass from fecal samples. We applied the model to data collected from harbor seals (Phoca vitulina) that are present year-round in the lower Columbia River where endangered stocks of salmonids pass as returning adults and as seaward-migrating smolts. Using the same data, we applied the split-sample frequency of occurrence model, which avoids reconstructing biomass by assuming that each fecal sample represents an equal volume of consumption and that within each sample each prey item represents an equal proportion of the volume. The two models for estimating diet composition yielded size-specific differences in consumption estimates that were as large as tenfold for the smallest and largest prey. Conclusions about the impact of harbor seal predation on adult salmonids, some of their largest prey species, remain uncertain without some appropriate rationale or further information (e.g. empirical captive studies) to discriminate between these models.

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A normalized difference vegetation index (NDVI) has been produced and archived on a 1° latitude by 1° longitude grid between 55°S and 75°N. The many sources of data errors in the NDVI include cloud contamination, scan angle biases, changes in solar zenith angle, and sensor degradation. Week-to-week variability, primarily caused by cloud contamination and scan angle biases, can be minimized by temporally filtering the data. Orbital drift and sensor degradation introduces interannual variability into the dataset. These trends make the usefulness of a long-term climatology uncertain and limit the usefulness of the NDVI. Elimination of these problems should produce an index that can be used for climate monitoring.

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Time series analysis methods have traditionally helped in identifying the role of various forcing mechanisms in influencing climate change. A challenge to understanding decadal and century-scale climate change has been that the linkages between climate changes and potential forcing mechanisms such as solar variability are often uncertain. However, most studies have focused on the role of climate forcing and climate response within a strictly linear framework. Nonlinear time series analysis procedures provide the opportunity to analyze the role of climate forcing and climate responses between different time scales of climate change. An example is provided by the possible nonlinear response of paleo-ENSO-scale climate changes as identified from coral records to forcing by the solar cycle at longer time scales.

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A one-dimensional ring-pack lubrication model developed at MIT is applied to simulate the oil film behavior during the warm-up period of a Kohler spark ignition engine [1]. This is done by making assumptions for the evolution of the oil temperatures during warm-up and that the oil control ring during downstrokes is fully flooded. The ring-pack lubrication model includes features such as three different lubrication regimes, i.e. pure hydrodynamic lubrication, boundary lubrication and pure asperity contact, non-steady wetting of both inlet and outlet of the piston ring, capability to use all ring face profiles that can be approximated by piece-wise polynomials and, finally, the ability to model the rheology of multi-grade oils. Not surprisingly, the simulations show that by far the most important parameter is the temperature dependence of the oil viscosity. This dependence is subsequently examined further by choosing different oils. The baseline oil is SAE 10W30 and results are compared to those using the SAE 30 and the SAE 10W50 oils.

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Growth of Encrasicholina punctifer (Engraulididae) is estimated, based on samples obtained during five surveys on Sofala Bank (central Mozambique). The estimated values of the von Bertalanffy growth function, TL∞=12 cm and K=2.0 yearˉ¹ are compared with results of growth studies elsewhere in the Indo-Pacific region, based mainly on the index Φ=log(sub)10 K+2*log(sub)10L∞ assumed to be constant within species. This comparison is rendered difficult by the uncertain taxonomical status of stolephorid anchovies.

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Lake Albert is one of the largest lakes in Uganda that still supports a multi-species fishery which as a result of variable adult sizes of the species, causes management challenges especially in relation to gear mesh size enforcement. Prior to the 1980s, commercial species were 17 largesized fishes especially Citharinus citharinus, Distichodus niloticus and Lates spp. that were confmed to inshore habitats of the lake and were thus rapidly over fished. Frame and catch assessment surveys conducted in this study revealed a >80% dominance of small size fish species (Neobola bredoi and Brycinus nurse) and a 40 -60% decrease in the contribution of the large commercial species. Sustainability of small size fish species is uncertain due to seasonal fluctuations and low beach value. At about 150,000 tons of fish recorded from Lake Albert and Albert Nile, the beach value was estimated at 55.3 million USD. Despite the noted decline in catches of the large sized fishes their contribution was more than 50% of total beach value. Therefore, management measures should couple value addition for the small sized species and maintain effort regulation targeting recovery of the large previously important commercial species