885 resultados para Microwave-assisted Solvothermal
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This paper studies the influence of hydraulics and control of thermal storage in systems combined with solar thermal and heat pump for the production of warm water and space heating in dwellings. A reference air source heat pump system with flat plate collectors connected to a combistore was defined and modeled together with the IEA SHC Task 44 / HPP Annex 38 (T44A38) “Solar and Heat Pump Systems” boundary conditions of Strasbourg climate and SFH45 building. Three and four pipe connections as well as use of internal and external heat exchangers for DHW preparation were investigated as well as sensor height for charging of the DHW zone in the store. The temperature in this zone was varied to ensure the same DHW comfort was achieved in all cases. The results show that the four pipe connection results in 9% improvement in SPF compared to three pipe and that the external heat exchanger for DHW preparation leads to a 2% improvement compared to the reference case. Additionally the sensor height for charging the DHW zone of the store should not be too low, otherwise system performance is adversely affected
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Mobile assisted language learning (MALL) is a subarea of the growing field of mobile learning (mLearning) research which increasingly attracts the attention of scholars. This study provides a systematic review of MALL research within the specific area of second language acquisition during the period 2007 - 2012 in terms of research approaches, methods, theories and models, as well as results in the form of linguistic knowledge and skills. The findings show that studies of mobile technology use in different aspects of language learning support the hypothesis that mobile technology can enhance learners’ second language acquisition. However, most of the reviewed studies are experimental, small-scale, and conducted within a short period of time. There is also a lack of cumulative research; most theories and concepts are used only in one or a few papers. This raises the issue of the reliability of findings over time, across changing technologies, and in terms of scalability. In terms of gained linguistic knowledge and skills, attention is primarily on learners’ vocabulary acquisition, listening and speaking skills, and language acquisition in more general terms.
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This paper describes the development of a new approach to the use of ICT for the teaching of courses in the interpretation and evaluation of evidence. It is based on ideas developed for the teaching of science to school children, in particular the importance of models and qualitative reasoning skills. In the first part, we make an analysis of the basis of current research into “evidence scholarship” and the demands such a system would have to meet. In the second part, we introduce the details of such a system that we developed initially to assist police in the interpretation of evidence.
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In this paper I examine the structure of the current assisted living industry in order to explain how and why it is appealing and effective, as well as look at its limitations. I discuss the politics of Medicaid and Medicare, and how through these programs the federal and state governments are failing to provide adequate care for the nation’s senior population. Like the rest of our health care system, these two public health insurance systems are fragmented, and consequently, financing long-term care is complicated and insufficient. Ultimately, this paper will function as a policy report and I will propose: standardized requirements for assisted living facilities; a stricter and new way to regulate assisted living on the state level; restructured models for the public insurance programs, including Medicaid, Medicare, and the State Children’s Health Insurance Program.
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Frequent advances in medical technologies have brought fonh many innovative treatments that allow medical teams to treal many patients with grave illness and serious trauma who would have died only a few years earlier. These changes have given some patients a second chance at life, but for others. these new treatments have merely prolonged their dying. Instead of dying relatively painlessly, these unfortunate patients often suffer from painful tenninal illnesses or exist in a comatose state that robs them of their dignity, since they cannot survive without advanced and often dehumanizing forms of treatment. Due to many of these concerns, euthanasia has become a central issue in medical ethics. Additionally, the debate is impacted by those who believe that patients have the right make choices about the method and timing of their deaths. Euthanasia is defined as a deliberate act by a physician to hasten the death of a patient, whether through active methods such as an injection of morphine, or through the withdrawal of advanced forms of medical care, for reasons of mercy because of a medical condition that they have. This study explores the question of whether euthanasia is an ethical practice and, as determined by ethical theories and professional codes of ethics, whether the physician is allowed to provide the means to give the patient a path to a "good death," rather than one filled with physical and mental suffering. The paper also asks if there is a relevant moral difference between the active and passive forms of euthanasia and seeks to define requirements to ensure fully voluntary decision making through an evaluation of the factors necessary to produce fully informed consent. Additionally, the proper treatments for patients who suffer from painful terminal illnesses, those who exist in persistent vegetative states and infants born with many diverse medical problems are examined. The ultimate conclusions that are reached in the paper are that euthanasia is an ethical practice in certain specific circumstances for patients who have a very low quality of life due to pain, illness or serious mental deficits as a result of irreversible coma, persistent vegetative state or end-stage clinical dementia. This is defended by the fact that the rights of the patient to determine his or her own fate and to autonomously decide the way that he or she dies are paramount to all other factors in decisions of life and death. There are also circumstances where decisions can be made by health care teams in conjunction with the family to hasten the deaths of incompetent patients when continued existence is clearly not in their best interest, as is the case of infants who are born with serious physical anomalies, who are either 'born dying' or have no prospect for a life that is of a reasonable quality. I have rejected the distinction between active and passive methods of euthanasia and have instead chosen to focus on the intentions of the treating physician and the voluntary nature of the patient's request. When applied in equivalent circumstances, active and passive methods of euthanasia produce the same effects, and if the choice to hasten the death of the patient is ethical, then the use of either method can be accepted. The use of active methods of euthanasia and active forms of withdrawal of life support, such as the removal of a respirator are both conscious decisions to end the life of the patient and both bring death within a short period of time. It is false to maintain a distinction that believes that one is active killing. whereas the other form only allows nature to take it's course. Both are conscious choices to hasten the patient's death and should be evaluated as such. Additionally, through an examination of the Hippocratic Oath, and statements made by the American Medical Association and the American College of physicians, it can be shown that the ideals that the medical profession maintains and the respect for the interests of the patient that it holds allows the physician to give aid to patients who wish to choose death as an alternative to continued suffering. The physician is also allowed to and in some circumstances, is morally required, to help dying patients whether through active or passive forms of euthanasia or through assisted suicide. Euthanasia is a difficult topic to think about, but in the end, we should support the choice that respects the patient's autonomous choice or clear best interest and the respect that we have for their dignity and personal worth.
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Este projecto foi realizado na Universidade da Madeira, no âmbito do Mestrado em Engenharia Informática e tem como título “Plataforma para o suporte de Blended Peer Assisted Learning”. Ao longo da nossa pesquisa sobre os vários métodos de aprendizagem online, deparamo-nos com uma grande lacuna que abrange a maior parte dos sistema de ensino assistidos por computador, ou seja, todas elas preocupam-se com a passagem de conhecimentos, mas raras são aquelas que têm em atenção o tipo de utilizador, qual a seu percurso académico e profissional, qual a metodologia que fará com que o mesmo capte melhor os conteúdos, etc. Com este objectivo em mente, e tendo em atenção as diversas plataformas e metodologias de ensino existentes, optou-se por elaborar uma arquitectura de uma plataforma capaz de centralizar na mesma, um conjunto de funcionalidades e metodologias que possibilitassem um acompanhamento mais específico do utilizador, proporcionando um maior conhecimento, através do qual poderia encaminhar o utilizador para a estratégia de aprendizagem que mais se adequasse a um utilizador com as suas características. Como se poderá constatar no decorrer desta dissertação, a plataforma desenhada e o módulo desenvolvido têm como base teórica o Peer Assisted Learning (PAL) e as suas estratégias de aprendizagem. O PAL é um conceito relativamente novo, que se encontra em plena ascensão, sendo cada vez maior o número de instituições/organizações que adoptam o PAL como metodologia de ensino para a formação dos seus membros. Este crescimento deve-se em grande parte às várias estratégias PAL que visam uma maior adequação ao tipo de utilizador, contribuindo assim para uma aprendizagem mais rápida e eficaz. Uma vez que a implementação da plataforma na sua totalidade seria de todo impossível, optouse por desenvolver apenas um dos módulos referente à estratégia de PAL – Peer Tutoring (PT). No final, o objectivo principal, passa não só por fornecer as bases necessárias ao desenvolvimento da referida plataforma, mas também pela disponibilização do módulo de PT que servirá de referência para o desenvolvimento das restantes estratégias. Tendo em atenção toda a investigação efectuada, facilmente se depreende as inúmeras vantagens que podem advir da utilização do PAL, das quais se salienta, a adequação da estratégia PAL mais indicada para cada tipo de utilizador.
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In this work, mixed oxides were synthesized by two methods: polymeric precursor and gel-combustion. The oxides, Niquelate of Lanthanum, Cobaltate of Lanthanum and Cuprate of Lanthanum were synthesized by the polymeric precursor method, and treated at 300 º C for 2 hours, calcined at 800 º C for 6h in air atmosphere. In gel-combustion method were produced and oxides using urea and citric acid as fuel, forming for each fuel the following oxides Ferrate of Lanthanum, Cobaltato of Lanthanum and Ferrato of Cobalt and Lanthanum, which were submitted to the combustion process assisted by microwave power maximum of 10min. The samples were characterized by: thermogravimetric analysis, X-ray diffraction; fisisorção of N2 (BET method) and scanning electron microscopy. The reactions catalytic of depolymerization of poly (methyl methacrylate), were performed in a reactor of silica, with catalytic and heating system equipped with a data acquisition system and the gas chromatograph. For the catalysts synthesized using the polymeric precursor method, the cuprate of lanthanum was best for the depolymerization of the recycled polymer, obtaining 100% conversion in less time 554 (min), and the pure polymer, was the Niquelate of Lanthanum, with 100% conversion in less time 314 (min). By gel-combustion method using urea as fuel which was the best result obtained Ferrate of Lanthanum for the pure polymer with 100% conversion in less time 657 (min), and the recycled polymer was Cobaltate of Lanthanum with 100 % conversion in less time 779 (min). And using citric acid to obtain the best result for the pure polymer, was Ferrate of Lanthanum with 100% conversion in less time 821 (min and) for the recycled polymer, was Ferrate of Lanthanum with 98.28% conversion in less time 635 (min)
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In recent decades have seen a sharp growth in the study area of nanoscience and nanotechnology and is included in this area, the study of nanocomposites with self-cleaning properties. Since titanium dioxide (TiO2) has high photocatalytic activity and also antimicrobial, self-cleaning surfaces in your application has been explored. In this study a comparison was made between two synthesis routes to obtain TiO2 nanoparticles by hydrothermal method assisted by microwave. And after analysis of XRD and SEM was considered the best material for use in nanocomposites. It was deposited nanocomposite film of poly (dimethyl siloxane) (PDMS) with 0.5, 1, 1.5 and 2% by weight of nanoparticles of titanium dioxide (TiO2) by the spraying method. The nanocomposite was diluted with hexane and the suspension was deposited onto glass substrate, followed by curing in an oven with forced air circulation. The photocatalytic activity of the nanocomposite impregnated with methylene blue was evaluated by UV- vis spectroscopy from the intensity variation of absorption main peak at 660nm with time of exposure to the UV chamber. Changes in the contact angle and microhardness were analyzed before and after UV aging test. The effect of ultraviolet radiation on the chemical structure of the PDMS matrix was evaluated by spectrophotometry Fourier transform infrared (FTIR).The results indicated that the addition of TiO2 nanoparticles in the coating PDMS gave high photocatalytic activity in the decomposition of methylene blue, an important characteristic for the development of self-cleaning coatings
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The objective of this study was to evaluate the quality of bovine frozen-thawed sperm cells after Percoll gradient centrifugation. Frozen semen doses were obtained from six bulls of different breeds, including three taurine and three Zebu animals. Four ejaculates per bull were evaluated before and after discontinuous Percoll gradient centrifugation. Sperm motility was assessed by computer-assisted semen analysis and the integrity of the plasma and acrosomal membranes, as well as mitochondrial function, were evaluated using a combination of fluorescent probes propidium iodide, fluorescein isothiocyanate-conjugated Pisum sativum agglutinin and 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolcarbocyanine iodide. The procedure of Percoll gradient centrifugation increased the percentage of total and progressive sperm motility, beat frequency, rectilinear motility, linearity and rapidly moving cells. In addition, the percentage of cells with intact plasma membrane and mitochondrial membrane potential was increased in post-centrifugation samples. However, the percentage of sperm cells with intact acrosomal membrane was markedly reduced. The method used selected the motile cells with intact plasma membrane and higher mitochondrial functionality in frozen-thawed bull semen, but processing, centrifugation and/or the Percoll medium caused damage to the acrosomal membrane.
Demecolcine Effects on Microtubule Kinetics and on Chemically Assisted Enucleation of Bovine Oocytes
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)