983 resultados para Tool materials
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This paper examines the effectiveness of urban containment policies to protect forestland from residential conversion and to increase the provision of forest public goods in the presence of irreversible investments and policy uncertainty. We develop a model of a single landowner that allows for switching between competing land uses (forestry and residential use) at some point in the future. Our results show that urban containment policies can protect (even if temporarily) forestland from being developed but must be supplemented with policies that influence the length and number of harvesting cycles if the goal is to increase nontimber benefits. The threat of a development prohibition creates incentives for preemptive timber harvesting and land conversion. In particular, threatened regulation creates an incentive to shorten rotation cycles to avoid costly land-use restrictions. However, it has an ambiguous effect on forestland conversion as the number of rotation cycles can also be adjusted to maximize the expected returns to land. Finally, in the presence of irreversibility, forestland conversion decisions should be done using real option theory rather than net present value analysis
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Confocal scanning fluorescence microscopy has become widely used in cell biology and pathology. In conjunction with monoclonal antibodies it may turn out to be a powerful diagnostic tool that also enables detailed studies of tissue forms of Trypanosoma cruzi.
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Dissertação para obtenção do Grau de Mestre em Engenharia Mecânica
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Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente Perfil de Engenharia de Sistemas Ambientais
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Chlamydia trachomatis has a unique obligate intracellular developmental cycle that ends by the lysis of the cell and/or the extrusion of the bacteria in order to allow for re-infections. While Chlamydia trachomatis infections are often asymptomatic the diagnosis of Chlamydia trachomatis is usually late, occurring after manifestation of persistency. Investigations on the consequences of long-term infections and the molecular mechanisms behind it will reveal light to what extent bacteria can modulate host cell function and what the ultimate fate of host cells after clearance of an infection is. Such studies on the host cell fate could be greatly facilitated if the infected cells become permanently marked during and after the infection. Therefore, this project intends to develop a new genetic tool that would allow permanently labeling of Chlamydia trachomatis host cells. The plan was to generate a Chlamydia trachomatis strain that encodes a recombinant CRE recombinase, fused to a secretory effector function of the Chlamydia type 3 secretion system (T3SS). Upon translocation into the host cell, this recombinant CRE enzyme could then, owing to its site-specific recombination function, switch a reporter gene contained in the host cell genome. To this end, the reporter line carried a membrane-tagged tdTomato (mT) gene flanked by two LoxP sequences followed by a GFP gene. The translocation of the recombinant CRE recombinase into this cell line was designed to trigger the recombination of the LoxP sites whereby the cells would turn from red fluorescence to green as an irreversible label of the infected cells. Successful execution of this mechanism would allow to draw a direct link between Chlamydia trachomatis infection and the subsequent fate of the infected cell.
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RESUMO: Este é o relatório de um estágio realizado na Autoridade de Saúde Local de Bolonha com o objectivo de desenvolver capacidades e competências na área de projectos orientados para a avaliação com base epidemiológica. As prescrições de anti-depressivos aumentaram consideravelmente em todo o mundo durante as últimas décadas. O uso cada vez maior dos agentes mais dispendiosos desempenha um papel na subida do custo dos tratamentos. A Autoridade de Saúde Local de Bolonha implementou um processo de auditoria com o objectivo de melhorar a adequação das prescrições de pacientes externos, centrando-se em dois anti-depressivos de marca ainda protegidos por patente, Escitalopram e Duloxetine. Os Departamentos de Cuidados de Saúde Primários e de Cuidados de Saúde Mental, assim como o Departamento Farmacêutico e a Unidade de Gestão Clínica, estiveram envolvidos na fase de planeamento da auditoria. O grupo da auditoria, maioritariamente composto por médicos de clínica geral e psiquiatras, reuniu e analisou provas da eficácia e segurança dos anti-depressivos. Os dados sobre as prescrições das Unidades de Cuidados de Saúde Primários e dos Centros de Saúde Mental Comunitários da Autoridade de Saúde Local (866.294 habitantes) foram comparados, em particular as taxas de consumo de Escitalopram e Duloxetine. O grupo da auditoria definiu os standards a serem abordados, os indicadores a serem avaliados e as medidas a empreender para atingir os objectivos definidos. As directrizes do NICE sobre a depressão foram escolhidas como referência. O objectivo da auditoria foi definido como evitar o Escitalopram e Duloxetine como medicamentos de primeira escolha num tratamento anti-depressivo. De modo a verificar a eficácia das medidas empreendidas foi seleccionado um indicador, consistindo numa redução de 25% das prescrições de ambos os anti-depressivos na prática clínica de pacientes externos e numa redução de 20% da variabilidade nas Unidades de Cuidados de Saúde Primários. O relatório retrospectivo pré-auditoria (Janeiro a Abril de 2012) revelou que os tratamentos com anti-depressivos para pacientes externos eram prescritos pelos médicos de clínica geral em mais de90% dos casos. As medidas da auditoria foram implementadas entre Novembro de 2012 e Maio de 2013. Algumas medidas relevantes foram integradas com a revisão da auditoria, tais como reuniões educacionais de pequena escala com os médicos de clínica geral e psiquiatras, visitas de apoio do assessor de prescrições da Autoridade de Saúde Local aos médicos de clínica geral e Centros de Saúde Mental Comunitários, panfletos para profissionais com informação retirada das directrizes clínicas do NICE, implementação de um serviço de consulta na Web para médicos de clínica geral sobre provas relativas a anti-depressivos. O relatório de feedback é aguardado em Novembro de 2013 depois de se verificar nos standards atingidos a eficácia das medidas implementadas. Foi realizada uma análise SWOT para comprovar as forças e fraquezas, as oportunidades e ameaças do processo. Como identificação de fraquezas poderá ser útil identificar estratégias relevantes para melhoria interna, para que o conhecimento das ameaças possa amortizar factores que possam ter impactos adversos que fujam ao controlo do Departamento de Saúde Mental. Uma melhor compreensão das forças e das oportunidades facilita a consecução dos objectivos estabelecidos no projecto. O primeiro, mas não o último, resultado deste processo consistiu numa maior integração entre os Cuidados de Saúde Primários e de Saúde Mental, permitindo assim que a Autoridade de Saúde Local coloque as alterações em prática.------------ABSTRACT: This is the report of a traineeship held in the Local Health Authority of Bologna with the aim to develop skills and competencies in the field of epidemiogically based evaluation oriented projects. Antidepressants prescriptions have considerably increased all over the world in the last decades. The increasing use of the most expensive agents plays a part in the rising cost of treatments. The Local Health Authority of Bologna has implemented an audit process aimed at improving the appropriateness of outpatient prescriptions focusing on the two branded antidepressants still protected by patent, Escitalopram and Duloxetine. The Primary Care and the Mental Health Care Departments, as well as the Pharmaceutical Department and the Clinical Governance Unit, were involved in the planning phase of the audit. The audit group, mainly composed of general practitioners and psychiatrists, collected and analyzed scientific evidence on effectiveness and safety of antidepressants. Data on prescriptions of Primary Care Units and Community Mental Health Centers of the Local Health Authority (866.294 inhabitants) were compared, in particular consumption rates of Escitalopram and Duloxetine. The audit group defined the standards to be addressed, the indicators to be evaluated and the actions aimed at reaching the defined goals. NICE guidelines on depression were chosen as reference. The aim of the audit was settled as avoiding Escitalopram and Duloxetine as first choice drugs starting an AD treatment. In order to check the efficacy of the actions undertaken an indicator was selected, consisting in a reduction of 25% of prescriptions of both ADs in outpatient practice and in a 20% reduction of To develop skills and competencies across Primary Care Units. The pre-audit retrospective report (January-April 2012) showed that outpatient antidepressant treatments were prescribed by GPs in over 90% of cases. Audit actions were implemented between November 2012 and May 2013. Some relevant actions have been integrated with the audit review, such as small-scale educational meetings with GPs and psychiatrists, outreach visits of the LHA prescribing adviser to GPs and CMHCs,leaflets for professionals with information extracted from NICE clinical guidelines, implementation of a web consultation service for GPs about evidence on antidepressants. The feedback report is expected in November 2013 after checking through the standards attained the effectiveness of actions implemented. A SWOT Analysis was carried out to evidence the strengths and weaknesses, opportunities and threats of the process. As identification of weaknesses may be useful to identify relevant strategies for internal improvement, so the knowledge of threats can amortize factors that may have adverse impacts beyond the control of the Mental Health Department. Better understanding of the strengths and the opportunities facilitates the achievement of the goals set in the project. The first and not least upshot of this process has consisted in further integration between Primary and Mental Health Care, thus enabling the LHA to put the change into practice.
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The main objective of this work was the development of polymeric structures, gel and films, generated from the dissolution of the Chitin-Glucan Complex (CGC) in biocompatible ionic liquids for biomedical applications. Similar as chitin, CGC is only soluble in some special solvents which are toxic and corrosive. Due to this fact and the urgent development of biomedical applications, the need to use biocompatible ionic liquids to dissolve the CGC is indispensable. For the dissolution of CGC, the biocompatible ionic liquid used was Choline acetate. Two different CGC’s, KiOnutrime from KitoZyme and biologically produced CGC from Faculdade de Ciencias e Tecnologia (FCT) - Universidade Nova de Lisboa, were characterized in order to develop biocompatible wound dressing materials. The similar result is shown in term of the ratio of chitin:glucan, which is 1:1.72 for CGC-FCT and 1:1.69 for CGC-Commercial. For the analysis of metal element content, water and inorganic salts content and protein content, both polymers showed some discrepancies, where the content in CGC-FCT is always higher compared to the commercial one. The different characterization results between CGC-FCT and CGC-Commercial could be addressed to differences in the purification method, and the difference of its original strain yeast, whereas CGC-FCT is derived from P.pastoris and the commercial CGC is from A.niger. This work also investigated the effect of biopolymers, temperature dissolution, non-solvent composition on the characteristics of generated polymeric structure with biocompatible ionic liquid. The films were prepared by casting a polymer mixture, immersion in a non-solvent, followed by drying at ambient temperature. Three different non-solvents were tested in phase inversion method, i.e. water, methanol, and glycerol. The results indicate that the composition of non-solvent in the coagulation bath has great influence in generated polymeric structure. Water was found to be the best coagulant for producing a CGC polymeric film structure. The characterizations that have been done include the analysis of viscosity and viscoelasticity measurement, as well as sugar composition in the membrane and total sugar that was released during the phase inversion method. The rheology test showed that both polymer mixtures exhibit a non- Newtonian shear thinning behaviour. Where the viscosity and viscoelasticity test reveal that CGCFCT mixture has a typical behaviour of a viscous solution with entangled polymer chains and CGCCommercial mixture has true gel behaviour. The experimental results show us that the generated CGC solution from choline acetate could be used to develop both polymeric film structure and gel. The generated structures are thermally stable at 100° C, and are hydrophilic. The produced films have dense structure and mechanical stabilities against puncture up to 60 kPa.
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Portuguese Science Foundation - project Electra PTDC/CTM/099124/2008 and the PhD grant SFRH/BD/45224. financial support: Professor E. Fortunato’s ERC 2008 Advanced Grant (INVISIBLE contract number 228144), “APPLE” FP7-NMP-2010-SME/262782-2 and “SMARTEC” FP7-ICT-2009.3.9/258203
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In this thesis, a predictive analytical and numerical modeling approach for the orthogonal cutting process is proposed to calculate temperature distributions and subsequently, forces and stress distributions. The models proposed include a constitutive model for the material being cut based on the work of Weber, a model for the shear plane based on Merchants model, a model describing the contribution of friction based on Zorev’s approach, a model for the effect of wear on the tool based on the work of Waldorf, and a thermal model based on the works of Komanduri and Hou, with a fraction heat partition for a non-uniform distribution of the heat in the interfaces, but extended to encompass a set of contributions to the global temperature rise of chip, tool and work piece. The models proposed in this work, try to avoid from experimental based values or expressions, and simplifying assumptions or suppositions, as much as possible. On a thermo-physical point of view, the results were affected not only by the mechanical or cutting parameters chosen, but also by their coupling effects, instead of the simplifying way of modeling which is to contemplate only the direct effect of the variation of a parameter. The implementation of these models was performed using the MATLAB environment. Since it was possible to find in the literature all the parameters for AISI 1045 and AISI O2, these materials were used to run the simulations in order to avoid arbitrary assumption.
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Enthesitis is the hallmark of spondyloarthritis and is observed in all subtypes. Namely, a wide information on spondyloarthritis abnormalities, including synovitis, bursitis, tendinitis, enthesitis and cortical bone abnormalities (erosions and enthesophytes), can be efficiently perceived by ultrasound power Doppler. Furthermore, several studies on imaging of enthesis showed that imaging techniques are better than clinical examination to detect pathology at asymptomatic enthesis. Vascularized enthesitis detected by ultrasound power Doppler appears to be a valuable diagnostic tool to confirm spondyloarthritis diagnosis. This article focuses on the validity and reliability of ultrasound enthesitis assessment in the management of spondyloarthritis patients.
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Phage display technology is a powerful platform for the generation of highly specific human monoclonal antibodies (Abs) with potential use in clinical applications. Moreover, this technique has also proven to be a reliable approach in identifying and validating new cancer-related targets. For scientific or medical applications, different types of Ab libraries can be constructed. The use of Fab Immune libraries allows the production of high quality and affinity antigen-specific Abs. In this work, two immune human phage display IgG Fab libraries were generated from the Ab repertoire of 16 breast cancer patients, in order to obtain a tool for the development of new therapeutic Abs for breast cancer, a condition that has great impact worldwide. The generated libraries are estimated to contain more than 108 independent clones and a diversity over 90%. Libraries validation was pursued by selection against BSA, a foreign and highly immunogenic protein, and HER2, a well established cancer target. Preliminary results suggested that phage pools with affinity for these antigens were selected and enriched. Individual clones were isolated, however, it was not possible to obtain enough data to further characterize them. Selection against the DLL1 protein was also performed, once it is a known ligand of the Notch pathway, whose deregulation is associated to breast cancer, making it an interesting target for the generation of function-blocking Abs. Selection resulted in the isolation of a clone with low affinity and Fab expression levels. The validation process was not completed and further effort will have to be put in this task in the future. Although immune libraries concept implies limited applicability, the library reported here has a wide range of use possibilities, since it was not restrained to a single antigen but instead thought to be used against any breast cancer associated target, thus being a valuable tool.
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This work is divided into two distinct parts. The first part consists of the study of the metal organic framework UiO-66Zr, where the aim was to determine the force field that best describes the adsorption equilibrium properties of two different gases, methane and carbon dioxide. The other part of the work focuses on the study of the single wall carbon nanotube topology for ethane adsorption; the aim was to simplify as much as possible the solid-fluid force field model to increase the computational efficiency of the Monte Carlo simulations. The choice of both adsorbents relies on their potential use in adsorption processes, such as the capture and storage of carbon dioxide, natural gas storage, separation of components of biogas, and olefin/paraffin separations. The adsorption studies on the two porous materials were performed by molecular simulation using the grand canonical Monte Carlo (μ,V,T) method, over the temperature range of 298-343 K and pressure range 0.06-70 bar. The calibration curves of pressure and density as a function of chemical potential and temperature for the three adsorbates under study, were obtained Monte Carlo simulation in the canonical ensemble (N,V,T); polynomial fit and interpolation of the obtained data allowed to determine the pressure and gas density at any chemical potential. The adsorption equilibria of methane and carbon dioxide in UiO-66Zr were simulated and compared with the experimental data obtained by Jasmina H. Cavka et al. The results show that the best force field for both gases is a chargeless united-atom force field based on the TraPPE model. Using this validated force field it was possible to estimate the isosteric heats of adsorption and the Henry constants. In the Grand-Canonical Monte Carlo simulations of carbon nanotubes, we conclude that the fastest type of run is obtained with a force field that approximates the nanotube as a smooth cylinder; this approximation gives execution times that are 1.6 times faster than the typical atomistic runs.
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The increasing use of information and communication technologies (ICT) in diverse professional and personal contexts calls for new knowledge, and a set of abilities, competences and attitudes, for an active and participative citizenship. In this context it is acknowledged that universities have an important role innovating in the educational use of digital media to promote an inclusive digital literacy. The educational potential of digital technologies and resources has been recognized by both researchers and practitioners. Multiple pedagogical models and research approaches have already contributed to put in evidence the importance of adapting instructional and learning practices and processes to concrete contexts and educational goals. Still, academic and scientific communities believe further investments in ICT research is needed in higher education. This study focuses on educational models that may contribute to support digital technology uses, where these can have cognitive and educational relevance when compared to analogical technologies. A teaching and learning model, centered in the active role of the students in the exploration, production, presentation and discussion of interactive multimedia materials, was developed and applied using the internet and exploring emergent semantic hypermedia formats. The research approach focused on the definition of design principles for developing class activities that were applied in three different iterations in undergraduate courses from two institutions, namely the University of Texas at Austin, USA and the University of Lisbon, Portugal. The analysis of this study made possible to evaluate the potential and efficacy of the model proposed and the authoring tool chosen in the support of metacognitive skills and attitudes related to information structuring and management, storytelling and communication, using computers and the internet.
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Evaporative cooling is a traditional strategy to improve summer comfort, which has gained renewed relevance in the context of the transition to a greener economy. Here, the potential for evaporative cooling of two common porous building materials, natural stone and ceramic brick, was evaluated. The work has relevance also to the protection of built heritage becauseevaporation underlies the problems of dampness and salt crystallization, which are so harmful and frequent in this heritage. It was observed that the drying rate of the materials is, in some cases, higher than the evaporation rate of a free water surface. Surface area measurements by a three-dimensional optical technique suggested, as probable cause of this behavior, that surface irregularity gives rise to a large effective surface of evaporation in the material. Surface temperature measurements by infrared were performed afterward during evaporation experiments outside during a hot summer day in Lisbon. Their results indicate that ordinary building materials can be very efficient evaporative media and, thus, may help in achieving higher energy efficiency while maintaining a simultaneous constructive or architectural function.
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Paper presented at the Colloquium Gerpisa 2013, Paris (http://gerpisa.org/node/2085), Session n°: 19 New kinds of mobility: old and new business models