642 resultados para EIS,


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As Inteligências Emocionais (IEs) têm sido objeto de estudo e discussão nos últimos quinze anos. Todavia, escassos são os estudos científicos, sobremaneira no campo da educação, voltados para o entendimento dos desafios e possibilidades das IEs no cenário do ensino superior. O modelo newtoniano-cartesiano, assumido por setores dominantes de nossa cultura de forma racionalista e reducionista, vem se estabelecendo desde tempos remotos, mais especificamente a partir do século XVI, avançando até os tempos atuais e trazendo muitas marcas para os diferentes campos da cultura ocidental, inclusive para a educação. Como características deste modelo, passíveis de crítica, estão a fragmentação do conhecimento, o foco na especialização e, a instituição de uma relação pedagógica dominadora e não dialogal que negligencia as múltiplas inteligências desenvolvidas e presentes nos indivíduos. Essas características contribuíram para o estabelecimento de uma sociedade de conhecimentos parcelares, para a disjunção entre sujeito e objeto, o descuido nas relações do homem para consigo mesmo, dele para com os demais homens e, dele para com os demais seres vivos que cohabitam o planeta, culminando numa intensa crise planetária. Urge discutir e rever o paradigma newtoniano-cartesiano, dado ao fato de que os resultados colhidos nestes últimos quinhentos anos, se por um lado nos beneficiaram do ponto de vista científico e tecnológico, não mais respondem aos problemas e necessidades com os quais nos deparamos, de modo especial na educação. Delimito esta pesquisa no âmbito do Ensino Superior e, no interior deste, no campo dos estudos de graduação em Administração. As perguntas que motivam o meu trabalho são: 1. Os professores do Curso de Administração consideram as dimensões emocionais em seu trabalho docente? 2. Eles sabem o que são IEs? 3. Que dificuldades eles vêem para desenvolver um trabalho com as dimensões emocionais? 4. Eles vêem possibilidades positivas no trabalho com as IEs? 5. Que pistas as respostas às perguntas acima sugerem à formação continuada de professores no campo da Administração? 6. Ao planejar e organizar suas aulas o professor tem vista o trabalho com a dimensão afetiva? Para fazer a crítica da educação construída na perspectiva newtoniano-cartesiana assumi como referências principais Morin (1995, 2000), Santos (1988) e Moraes (1997). Para estudar a construção do conhecimento considerando as IEs tomei como referências para esta pesquisa Gardner (1995), Izquierdo (2002) e Valle (2003). Foi realizada uma pesquisa de campo com seis (6) professores de um Curso de Administração, mediante um questionário estruturado. O objetivo desta pesquisa foi identificar as principais dificuldades dos docentes quando se pensa num trabalho pedagógico sensível às inteligências emocionais e, estudando estas dificuldades à luz dos teóricos por mim trazidos, construírem possíveis pistas para uma ação formativa, na perspectiva da formação continuada, que considere também o determinante das inteligências emocionais.(AU)

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A pesquisa analisou as tendências de formação de professores na perspectiva da educação inclusiva ante as exigências do cotidiano escolar que desde a década de 1990 vem apresentando uma demanda crescente de estudantes com necessidades educacionais especiais nas salas comuns do ensino regular. A inclusão escolar é um processo que depende da combinação de vários fatores, não é responsabilidade apenas do professor. Entretanto, questionamos: Será que os professores estão sendo preparados para pensar nesta perspectiva, de planejar para a diversidade da sala de aula, especialmente na vertente de alunos com deficiência intelectual, de realizar um trabalho em equipe com professores especialistas? A reflexão sobre a formação e a prática de professores na sala de aula inclusiva faz parte do processo de inclusão, ainda em construção. Eis a questão que norteou esta pesquisa, no sentido de revelar impactos das políticas de inclusão escolar nos cursos de formação de professores e na prática docente, revelando conflitos, resistências, contradições, avanços e mecanismos de exclusão implícitos na proposta da inclusão, contribuindo ainda, para a discussão sobre o papel da universidade como locus privilegiado de formação docente. Os resultados da pesquisa apontaram para uma superficialidade na formação de professores na perspectiva da educação inclusiva. A ação investigativa articulou as políticas públicas de formação de professores, as Diretrizes Curriculares Nacionais para as licenciaturas, os dispositivos legais, a sustentação teórica e os instrumentos de investigação para coordenadores, estudantes de Pedagogia e de Letras e professores do Ensino Fundamental em exercício.

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The self-assembly of cobalt coordination frameworks (Co-CPs) with a two-dimensional morphology is demonstrated by a solvothermal method. The morphology of the Co-CPs has been controlled by various solvothermal conditions. The two-dimensional nanostructures agglomerated by Co3O4 nanoparticles remained after the pyrolysis of the Co-CPs. The as-synthesized Co3O4 anode material is characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge measurements. The morphology of Co3O4 plays a crucial role in the high performance anode materials for lithium batteries. The Co3O4 nanoparticles with opened-book morphology deliver a high capacity of 597 mA h g-1 after 50 cycles at a current rate of 800 mA g-1. The opened-book morphology of Co3O4 provides efficient lithium ion diffusion tunnels and increases the electrolyte/Co3O4 contact/interfacial area. At a relatively high current rate of 1200 mA g-1, Co3O4 with opened-book morphology delivers an excellent rate capability of 574 mA h g-1.

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Local Government Authorities (LGAs) are mainly characterised as information-intensive organisations. To satisfy their information requirements, effective information sharing within and among LGAs is necessary. Nevertheless, the dilemma of Inter-Organisational Information Sharing (IOIS) has been regarded as an inevitable issue for the public sector. Despite a decade of active research and practice, the field lacks a comprehensive framework to examine the factors influencing Electronic Information Sharing (EIS) among LGAs. The research presented in this paper contributes towards resolving this problem by developing a conceptual framework of factors influencing EIS in Government-to-Government (G2G) collaboration. By presenting this model, we attempt to clarify that EIS in LGAs is affected by a combination of environmental, organisational, business process, and technological factors and that it should not be scrutinised merely from a technical perspective. To validate the conceptual rationale, multiple case study based research strategy was selected. From an analysis of the empirical data from two case organisations, this paper exemplifies the importance (i.e. prioritisation) of these factors in influencing EIS by utilising the Analytical Hierarchy Process (AHP) technique. The intent herein is to offer LGA decision-makers with a systematic decision-making process in realising the importance (i.e. from most important to least important) of EIS influential factors. This systematic process will also assist LGA decision-makers in better interpreting EIS and its underlying problems. The research reported herein should be of interest to both academics and practitioners who are involved in IOIS, in general, and collaborative e-Government, in particular. © 2013 Elsevier Ltd. All rights reserved.

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Recent advances in the electric & hybrid electric vehicles and rapid developments in the electronic devices have increased the demand for high power and high energy density lithium ion batteries. Graphite (theoretical specific capacity: 372 mAh/g) used in commercial anodes cannot meet these demands. Amorphous SnO2 anodes (theoretical specific capacity: 781 mAh/g) have been proposed as alternative anode materials. But these materials have poor conductivity, undergo a large volume change during charging and discharging, large irreversible capacity loss leading to poor cycle performances. To solve the issues related to SnO2 anodes, we propose to synthesize porous SnO2 composites using electrostatic spray deposition technique. First, porous SnO2/CNT composites were fabricated and the effects of the deposition temperature (200, 250, 300 °C) & CNT content (10, 20, 30, 40 wt %) on the electrochemical performance of the anodes were studied. Compared to pure SnO2 and pure CNT, the composite materials as anodes showed better discharge capacity and cyclability. 30 wt% CNT content and 250 °C deposition temperature were found to be the optimal conditions with regard to energy capacity whereas the sample with 20% CNT deposited at 250 °C exhibited good capacity retention. This can be ascribed to the porous nature of the anodes and the improvement in the conductivity by the addition of CNT. Electrochemical impedance spectroscopy studies were carried out to study in detail the change in the surface film resistance with cycling. By fitting EIS data to an equivalent circuit model, the values of the circuit components, which represent surface film resistance, were obtained. The higher the CNT content in the composite, lower the change in surface film resistance at certain voltage upon cycling. The surface resistance increased with the depth of discharge and decreased slightly at fully lithiated state. Graphene was also added to improve the performance of pure SnO2 anodes. The composites heated at 280 °C showed better energy capacity and energy density. The specific capacities of as deposited and post heat-treated samples were 534 and 737 mAh/g after 70 cycles. At the 70th cycle, the energy density of the composites at 195 °C and 280 °C were 1240 and 1760 Wh/kg, respectively, which are much higher than the commercially used graphite electrodes (37.2–74.4 Wh/kg). Both SnO2/CNTand SnO2/grapheme based composites with improved energy densities and capacities than pure SnO2 can make a significant impact on the development of new batteries for electric vehicles and portable electronics applications.

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Knowledge of cell electronics has led to their integration to medicine either by physically interfacing electronic devices with biological systems or by using electronics for both detection and characterization of biological materials. In this dissertation, an electrical impedance sensor (EIS) was used to measure the electrode surface impedance changes from cell samples of human and environmental toxicity of nanoscale materials in 2D and 3D cell culture models. The impedimetric response of human lung fibroblasts and rainbow trout gill epithelial cells when exposed to various nanomaterials was tested to determine their kinetic effects towards the cells and to demonstrate the biosensor's ability to monitor nanotoxicity in real-time. Further, the EIS allowed rapid, real-time and multi-sample analysis creating a versatile, noninvasive tool that is able to provide quantitative information with respect to alteration in cellular function. We then extended the application of the unique capabilities of the EIS to do real-time analysis of cancer cell response to externally applied alternating electric fields at different intermediate frequencies and low-intensity. Decreases in the growth profiles of the ovarian and breast cancer cells were observed with the application of 200 and 100 kHz, respectively, indicating specific inhibitory effects on dividing cells in culture in contrast to the non-cancerous HUVECs and mammary epithelial cells. We then sought to enhance the effects of the electric field by altering the cancer cell's electronegative membrane properties with HER2 antibody functionalized nanoparticles. An Annexin V/EthD-III assay and zeta potential were performed to determine the cell death mechanism indicating apoptosis and a decrease in zeta potential with the incorporation of the nanoparticles. With more negatively charged HER2-AuNPs attached to the cancer cell membrane, the decrease in membrane potential would thus leave the cells more vulnerable to the detrimental effects of the applied electric field due to the decrease in surface charge. Therefore, by altering the cell membrane potential, one could possibly control the fate of the cell. This whole cell-based biosensor will enhance our understanding of the responsiveness of cancer cells to electric field therapy and demonstrate potential therapeutic opportunities for electric field therapy in the treatment of cancer.

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Owing to an increased risk of aging population and a higher incidence of coronary artery disease (CAD), there is a need for more reliable and safer treatments. Numerous varieties of durable polymer-coated drug eluting stents (DES) are available in the market in order to mitigate in-stent restenosis. However, there are certain issues regarding their usage such as delayed arterial healing, thrombosis, inflammation, toxic corrosion by-products, mechanical stability and degradation. As a result, significant amount of research has to be devoted to the improvement of biodegradable polymer-coated implant materials in an effort to enhance their bioactive response. ^ In this investigation, magneto-electropolished (MEP) and a novel biodegradable polymer coated ternary Nitinol alloys, NiTiTa and NiTiCr were prepared to study their bio and hemocompatibility properties. The initial interaction of a biomaterial with its surroundings is dependent on its surface characteristics such as, composition, corrosion resistance, work of adhesion and morphology. In-vitro corrosion tests such as potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) studies were conducted to determine the coating stability and longevity. In-vitro hemocompatibility studies and HUVEC cell growth was performed to determine their thrombogenic and biocompatibility properties. Critical delamination load of the polymer coated Nitinol alloys was determined using Nano-scratch analysis. Sulforhodamine B (SRB) assays were performed to elucidate the effect of metal ions leached from Nitinol alloys on the viability of HUVEC cells. Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS), contact angle meter and X-ray diffraction (XRD) were used to characterize the surface of the alloys. ^ MEP treated and polymer coated (PC) Nitinol alloys displayed a corrosion resistant polymer coating as compared to uncoated alloys. MEP and PC has resulted in reduced Ni and Cr ion leaching from NiTi5Cr and subsequently low cytotoxicity. Thrombogenicity tests revealed significantly less platelet adhesion and confluent endothelial cell growth on polymer coated and uncoated ternary MEP Nitinol alloys. Finally, this research addresses the bio and hemocompatibility of MEP + PC ternary Nitinol alloys that could be used to manufacture blood contacting devices such as stents and vascular implants which can lead to lower U.S. healthcare spending.^

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Acknowledgements: We would like to thank Hanna Bensch and Hannes Weise for assistance with the collection of samples in the field. This work was supported by the Biodiversity and Ecosystem Services in a Changing Climate (BECC; a joint Lund-Gothenburg University initiative), the Swedish Research Council (EIS, BH), the Crafoord Foundation (EIS, BH), the Swedish Royal Society (EIS), ‘Gyllenstiernska Krapperupstiftelsen (EIS), the Wenner-Gren Foundations (postdoctoral stipend to RYD), EU FP7 (Marie Curie International Incoming Fellowship to RYD), the Kungliga Fysiografiska Sällskapet i Lund (MW) and the Helge Ax:son Johnson Stiftelse (MW). B.H. and E.I.S. conceived of the study. L.L. developed the hypotheses to be tested. L.L. and R.D. collected the field data and samples. All six authors contributed to planning RNA-seq analyses. P.C. and L.L. analysed the data. L.L. wrote the manuscript, which all six authors edited.

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Owing to an increased risk of aging population and a higher incidence of coronary artery disease (CAD), there is a need for more reliable and safer treatments. Numerous varieties of durable polymer-coated drug eluting stents (DES) are available in the market in order to mitigate in-stent restenosis. However, there are certain issues regarding their usage such as delayed arterial healing, thrombosis, inflammation, toxic corrosion by-products, mechanical stability and degradation. As a result, significant amount of research has to be devoted to the improvement of biodegradable polymer-coated implant materials in an effort to enhance their bioactive response. In this investigation, magneto-electropolished (MEP) and a novel biodegradable polymer coated ternary Nitinol alloys, NiTiTa and NiTiCr were prepared to study their bio and hemocompatibility properties. The initial interaction of a biomaterial with its surroundings is dependent on its surface characteristics such as, composition, corrosion resistance, work of adhesion and morphology. In-vitro corrosion tests such as potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) studies were conducted to determine the coating stability and longevity. In-vitro hemocompatibility studies and HUVEC cell growth was performed to determine their thrombogenic and biocompatibility properties. Critical delamination load of the polymer coated Nitinol alloys was determined using Nano-scratch analysis. Sulforhodamine B (SRB) assays were performed to elucidate the effect of metal ions leached from Nitinol alloys on the viability of HUVEC cells. Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS), contact angle meter and X-ray diffraction (XRD) were used to characterize the surface of the alloys. MEP treated and polymer coated (PC) Nitinol alloys displayed a corrosion resistant polymer coating as compared to uncoated alloys. MEP and PC has resulted in reduced Ni and Cr ion leaching from NiTi5Cr and subsequently low cytotoxicity. Thrombogenicity tests revealed significantly less platelet adhesion and confluent endothelial cell growth on polymer coated and uncoated ternary MEP Nitinol alloys. Finally, this research addresses the bio and hemocompatibility of MEP + PC ternary Nitinol alloys that could be used to manufacture blood contacting devices such as stents and vascular implants which can lead to lower U.S. healthcare spending.

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The air trapped in freshly formed ice gives information concerning the ice formation processes as weH as concerning severa,l environmental parameters at the time of ice formation. Air arnount, air composition, and the size and form of bubbles may change with time. Possible processes responsible for such changes are discussed. In very cold ice air content and air composition remain almost unchanged. Samples of ancient atmospheric air are therefore very weH preserved in cold ice. In temperate ice changes of the air amount and air composition depend on the intergranular water fiow through the glacier. This waterfiow can be estimated by measuring air amount and air composition in ice sampIes.

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Natural ice is formed by freezing of water or by sintering of dry or wet snow. Each of these processes causes atmospheric air to be enclosed in ice as bubbles. The air amount and composition as well as the bubble sizes and density depend not only on the kind of process but also on several environmental conditions. The ice in the deepest layers of the Greenland and thc Antarctic ice sheet was formed more than 100 000 years ago. In the bubbles of this ice, samples of atmospheric air from that time are preserved. The enclosure of air is discussed for each of the three processes. Of special interest are the parameters which control the amount and composition of the enclosed air. If the ice is formed by sintering of very cold dry snow, the air composition in the bubbles corresponds with good accuracy to the composition of atmospheric air.

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La0.8Sr0.2Ga0.8Mg0.2O3-δ (LSGM), a promising electrolyte material for intermediate temperature solid oxide fuel cells, can be sintered to a fully dense state by a flash-sintering technique. In this work, LSGM is sintered by the current-limiting flash-sintering process at 690°C under an electric field of 100 V cm-1, in comparison with up to 1400°C or even higher temperature in conventional furnace sintering. The resultant LSGM samples are investigated by scanning electron microscopy, X-ray diffraction, and electrochemical impedance spectroscopy. The SEM images exhibit well-densified microstructures while XRD results show that the perovskite structure after flash-sintering does not changed. EIS results show that the conductivity of LSGM sintered by the current-limiting flash-sintering process increases with sintering current density value. The conductivity of samples sintered at 120 mA mm-2 reaches 0.049 σ cm-1 at 800°C, which is approximate to the value of conventional sintered LSGM samples at 1400°C. Additionally, the flash-sintering process is interpreted by Joule heating theory. Therefore, the current-limiting flash-sintering technique is proved to be an energy-efficient and eligible approach for the densification of LSGM and other materials requiring high sintering temperature.

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In this work, Pr0.6Sr0.4FeO3-δ -Ce0.9Pr0.1O2-δ (PSFO-CPO) nanofibers were synthesized by a one-step electrospin technique for use in intermediate-temperature solid oxide fuel cell (IT-SOFC) applications. PSFO-CPO nanofibers were produced with a diameter of about 100nm and lengths exceeding tens of microns. The thermal expansion coefficient (TEC) matches with standard GDC electrolytes and the resulting conductivity also satisfies the needs of IT-SOFCs cathodes. EIS analysis of the nanofiber structured electrode gives a polarization resistance of 0.072Ωcm2 at 800°C, smaller than that from the powdered cathode with the same composition. The excellent electrochemical performance can be attributed to the well-constructed microstructure of the nanofiber structured cathode, which promotes surface oxygen diffusion and charge transfer processes. All the results imply that the one-step electrospin method is a facile and practical way of improving the cathode properties and that PSFO-CPO is a promising cathode material for IT-SOFCs.