999 resultados para locomotor strategies


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The purpose of the project is to improve our understanding about best management practices that can be utilized on diked managed wetlands in Suisun Marsh for reducing the occurrence of low dissolved oxygen (DO) and high methylmercury (MeHg) events associated primarily with fall flood-up practices. Low DO events are of concern because they can lead to undue stress and even mortality of sensitive aquatic organisms. Elevated MeHg levels are of concern because MeHg is a neurotoxin that bio-magnifies up the food chain and can cause deleterious effects to higher trophic level consumers such as piscivorous fish, birds, and mammals (including humans). This study involved two years (2007-2008) of intensive field data collection at two managed wetland sites in northwest Suisun Marsh and their surrounding tidal sloughs, an area with prior documented low DO events. In addition, the study collected limited soils and water quality field data and mapped vegetation for three managed wetland sites in the central interior of Suisun Marsh, for the purpose of examining whether wetlands at other locations exhibit characteristics that could indicate potential for similar concerns. In Year 1 of the study, the objective was to identify the baseline conditions in the managed wetlands and determine which physical management conditions could be modified for Year 2 to reduce low DO and MeHg production issues most effectively. The objective of Year 2 was to evaluate the effectiveness of these modified management actions at reducing production of low DO and elevated MeHg conditions within the managed wetlands and to continue improving understanding of the underlying biogeochemical processes at play. This Final Evaluation Memorandum examined a total of 19 BMPs, 14 involving modified water management operations and the remaining five involving modified soil and vegetation management practices. Some of these BMPs were previously employed and others have not yet been tested. For each BMP this report assesses its efficacy in improving water quality conditions and potential conflicts with wetland management. It makes recommendations for further study (either feasibility assessments or field testing) and whether to consider for future use. Certain previously used BMPs were found to be important contributors to poor water quality conditions and their continued use is not recommended. Some BMPs that could improve water quality conditions appear difficult to implement in regards to compatibility with wetland management; these BMPs require further elaboration and feasibility assessment to determine whether they should be field tested. In practice for any given wetland, there is likely a combination of BMPs that would together have the greatest potential to address the low DO and high MeHg water quality concerns. Consequently, this report makes no sweeping recommendations applicable to large groups of wetlands but instead promotes a careful consideration of factors at each wetland or small groups of wetlands and from that assessment to apply the most effective suite of BMPs. This report also identifies a number of recommended future actions and studies. These recommendations are geared toward improving the process understanding of factors that promote low DO and high MeHg conditions, the extent of these problems in Suisun Marsh, the regulatory basis for the DO standards for a large estuarine marsh, the economics of BMPs, and alternative approaches to BMPs on diked managed wetlands that may address the water quality issues. The most important of these recommendations is that future BMP implementation should be carried out within the context of rigorous scientific evaluation so as to gain the maximum improvement in how to manage these water quality issues in the diked managed wetlands of Suisun Marsh.

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O objetivo desta dissertação é analisar contos selecionados e o romance Under the Feet of Jesus da escritora chicana Helena María Viramontes, enfocando a apropriação de mitos astecas e lendas mexicanas protagonizados por figuras femininas, históricas ou míticas, como La Manlinche, La Llorona e The Hungry Woman. Esta re-visão crítica do passado tem um papel vital para as chicanas, reais e ficcionais, ao enfrentarem o domínio patriarcal, colonial e neocolonial. Devido à complexidade gerada pela ausência de linearidade narrativa, tanto nos contos como no romance, tornou-se necessária uma breve análise das estratégias narrativas a fim de ilustrar como tais estratégias estão intrinsecamente ligadas à apresentação fragmentada da vida dos trabalhadores migrantes. Foi igualmente indispensável examinar as demais práticas narrativas da autora tais como focalização, desconstrução, simultaneidade e justaposição, assim como o elo, por ela proposto em Under the Feet of Jesus, entre leitura, identidade, e engajamento com o mundo para promover a transformação social

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Objective: analyze and propose a theoretical model that describes blood donor decisions to help staff working in blood banks (nurses and others) in their efforts to capture and retain donors. Methods: analysis of several studies on the motivations to give blood in Spain over the last six years, as well as past literature on the topic, the authors' experiences in the last 25 years in over 15 Non Governmental Organizations with different levels of responsibilities, their experiences as blood donors and the informal interviews developed during those 25 years. Results: a model is proposed with different internal and external factors that influence blood donation, as well as the different stages of the decision-making process. Conclusion: the knowledge of the donation process permits the development of marketing strategies that help to increase donors and donations.

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Smart Grids are becoming a reality all over the world. Nowadays, the research efforts for the introduction and deployment of these grids are mainly focused on the development of the field of Smart Metering. This emerging application requires the use of technologies to access the significant number of points of supply (PoS) existing in the grid, covering the Low Voltage (LV) segment with the lowest possible costs. Power Line Communications (PLC) have been extensively used in electricity grids for a variety of purposes and, of late, have been the focus of renewed interest. PLC are really well suited for quick and inexpensive pervasive deployments. However, no LV grid is the same in any electricity company (utility), and the particularities of each grid evolution, architecture, circumstances and materials, makes it a challenge to deploy Smart Metering networks with PLC technologies, with the Smart Grid as an ultimate goal. This paper covers the evolution of Smart Metering networks, together with the evolution of PLC technologies until both worlds have converged to project PLC-enabled Smart Metering networks towards Smart Grid. This paper develops guidelines over a set of strategic aspects of PLC Smart Metering network deployment based on the knowledge gathered on real field; and introduces the future challenges of these networks in their evolution towards the Smart Grid.

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Comunicacion a congreso (Presentación): ICCC 40. International Conference on Coordination Chemistry. Valencia, September 09-13, 2012

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Some results of a line of research explored by the author in recent years, and concerning the small-scale fisheries of Mexico are discussed. Clarity of goals for fisheries management is stressed as a departure point before taking any step towards model building. Age-structured simulation models require input data and parameters such as growth rates, natural mortality, age at first capture and maturity, longevity, the longest possible catch records series, and estimates of numbers caught per age group. The link between each cohort and the following can then be established by means of the Ricker stock recruitment or the Beverton-Holt models. Simulation experiments can then be carried out by changing fishing mortality. Whenever data on profits and costs and catch are available, these can also be analyzed. The use of simulation models is examined with emphasis on the benefits derived from their use for fisheries management.