874 resultados para Barrier to trade
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Among people living with HIV (PLWH), adherence to antiretroviral therapy (ART) can be affected by problems of neurocognitive (NC) impairment, stress, alcohol and other drug (AOD) abuse, and other barriers. The aims of this research were to: (1) examine factors associated with NC impairment, (2) explore relationships between psychosocial variables with ART adherence and viral load (VL), and (3) evaluate the efficacy of an evidence-based intervention in improving ART adherence, increasing service utilization, and decreasing VL. The first study (n=370) was cross sectional and used structural equation modeling to test whether AOD use, years living with HIV, and time from HIV diagnosis to seeking care were associated with poorer NC functioning. The second study (n=246) used similar methods to test the hypothesis that stress, barriers to adherence, NC impairment, poor social support, and AOD use were related to lower VL mediated by ART adherence. The third study (n=243) evaluated an evidence-based, eight-session program to improve ART adherence, reduce VL, and increase service utilization in a randomized controlled trial. Study participants were PLWH living in South Florida, 18 to 60 years old, with a history of alcohol abuse enrolled from January 2009 through November 2012. Secondary analysis of available data showed: (1) scores on interference with executive functioning increased by 0.32 for each day of marijuana use and 1.18 for each year living with HIV, but no association was found between alcohol use and NC functioning; (2) each barrier to adherence was associated with a 10% decrease in adherence to ART and a 0.42 unit increase in VL (log10) and the relationship between barriers and VL was partially mediated by ART adherence; (3) participants in the evidence-based program were more likely than the comparison group to report an undetectable VL (OR=2.25, p Psychosocial factors affect VL, but ART adherence is essential in achieving an undetectable VL in PLWH.
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We propose a model, based on the work of Brock and Durlauf, which looks at how agents make choices between competing technologies, as a framework for exploring aspects of the economics of the adoption of privacy-enhancing technologies. In order to formulate a model of decision-making among choices of technologies by these agents, we consider the following: context, the setting in which and the purpose for which a given technology is used; requirement, the level of privacy that the technology must provide for an agent to be willing to use the technology in a given context; belief, an agent’s perception of the level of privacy provided by a given technology in a given context; and the relative value of privacy, how much an agent cares about privacy in this context and how willing an agent is to trade off privacy for other attributes. We introduce these concepts into the model, admitting heterogeneity among agents in order to capture variations in requirement, belief, and relative value in the population. We illustrate the model with two examples: the possible effects on the adoption of iOS devices being caused by the recent Apple–FBI case; and the recent revelations about the non-deletion of images on the adoption of Snapchat.
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Les maladies inflammatoires de l’intestin (MIIs, [MIM 266600]) sont caractérisées par une inflammation chronique au niveau du tube gastro-intestinal. Les deux principales formes sont la maladie de Crohn (MC) et la colite ulcéreuse (CU). Les MIIs résulteraient d’un défaut du système immunitaire et de l’épithélium intestinal. Ce dernier forme une barrière physique et biochimique qui sépare notre système immunitaire des microorganismes commensaux et pathogènes de la microflore intestinale. Un défaut dans la barrière épithéliale intestinale pourrait donc mener à une réponse immunitaire soutenue contre notre microflore intestinale. Les études d’association pangénomiques (GWAS) ont permis d’identifier 201 régions de susceptibilité aux MIIs. Parmi celles-ci, la région 1q32 associée à la MC (p<2x10-11) et à la CU (p<6x10-7) contient 4 gènes, dont C1orf106, un gène codant pour une protéine de fonction inconnue. Le re-séquençage de la région 1q32 a permis d’identifier une variante génétique rare de C1orf106 (MAF˂1%) associée aux MIIs (p=0,009), Y333F. Nous avons démontré que la substitution de la tyr333 par une phénylalanine semble avoir un effet sur la stabilité protéique de C1orf106 tel que démontré lors de l’inhibition de la synthèse protéique induite par le cycloheximide. Nous avons déterminé que C1orf106 est exprimé dans le côlon et l’intestin grêle. De plus, son expression est augmentée lors de la différenciation des cellules épithéliales Caco-2 en épithélium intestinal polarisé. Son profil d’expression correspond aux types cellulaires et tissulaires affectés dans les MIIs. De plus, C1orf106 est partiellement co-localisée avec le marqueur des jonctions serrées, ZO-1. Toutefois, son marquage reproduit parfaitement celui du marqueur des jonctions adhérentes, E-cadhérine. Les jonctions serrées et adhérentes sont localisées du côté apical de la jonction intercellulaire et sont toutes deux impliquées dans l’établissement de la barrière épithéliale. Nous avons donc testé l’impact de C1orf106 sur la perméabilité de l’épithélium intestinal. Nous avons observé une augmentation de la perméabilité épithéliale chez un épithélium intestinal formé par des cellules Caco-2 sous-exprimant C1orf106. Nos résultats suggèrent que C1orf106 pourrait être le gène causal de la région 1q32.
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Pain is defined since 1979 by the International Association for the Study of Pain (IASP) as "unpleasant subjective, sensory and emotional experience associated with actual or potential damage of tissue", with the concept more acceptable in our days. The Intensive Care Unit (ICU) is a complex environment to assess pain, where the difficulty in communication with the patient is the biggest barrier to getting your "selfreport", which is considered the gold standard in pain assessment. Many factors alter communication with critically ill patients, as the low level of consciousness, mechanical ventilation, sedation, and the patient's own pathology, besides, there are other limitations such as excessive technology or devices that can divert professional attention to the patient's pain behavior, and lack of training and guidance for management. The multicenter study SUPPORT, it showed that 50-65% of critical patients included suffered pain, and 15% of them reported moderate to severe intensity for more than half the period of hospitalization. Critically ill patients experience pain due to high volume of potentially painful techniques applied to them during their ICU admission, emphasizing nursing care and tracheal suctioning, mobilization, wound healing and channeling of catheters and others. The underestimation of pain involves physiological and hemodynamic effects such as increased blood pressure and/or heart rate, altered breathing pattern, and psychological and anxiety. Also an increase of sedation and mechanical ventilation time and ICU stay of increasing the morbidity and mortality of critically ill patients...
Resumo:
No âmbito da Medicina Dentária define como Paciente com Necessidades Especiais (PNE) todos o indivíduo que apresenta determinados desvios dos padrões de normalidade, identificáveis ou não e que por isso necessitam de atenção e abordagens especiais por um período da sua vida ou indefinidamente. De acordo com a Organização Mundial de Saúde (OMS), cerca de 10% da população mundial é constituída por pacientes especiais, sendo 50% portadores de deficiência mental, 20% de deficiência física, 15% de deficiência auditiva, 5% de deficiência visual e, 10% de alterações múltiplas. Indivíduos com necessidades especiais têm um risco elevado de ter doenças orais. Se, por um lado, um dos grandes objetivos deste trabalho é realçar a importância da higiene oral, não será menos importante, por outro lado, refletir sobre a eficácia da remoção do biofilme dentário através da técnica mais adequada para pacientes com necessidades educativas especiais. Assim, os principais objetivos deste estudo são: i. Perceber previamente ao estudo, quais as noções de higiene oral dos encarregados de educação dos alunos com necessidades educativas especiais e os hábitos de saúde oral que lhes estão associados; ii. Promover e melhorar a saúde oral desta população através de técnicas de motivação como jogos, apresentações de slides através do programa Microsoft powerpoint, filmes; iii. Levar os alunos com NEE a aprender a técnica mais adaptada às suas necessidades através do treino em macromodelos; iv. Comparar os valores do índice de placa no início e no final do estudo para perceber se houve ou não melhoria. Foi utilizada a base de dados do Pubmed, tendo sido pesquisados artigos com as palavras-chave “dental care in special children”, “especial needs”, “oral hygiene”, “oral health”; “deaf children and oral health”, “dental plaque” e “mechanic plaque control”. Foram incluídos os artigos escritos em Português e Inglês, aos quais houvesse acesso integral do artigo, dos últimos 10 anos. Foi realizada também uma consulta de livros relacionados com o tema. A população alvo foram os utentes da instituição CERCIPENICHE, portadores de dificuldade intelectual e desenvolvimental (DID) que compreendiam idades entre os 20 e os 57 anos. A amostra é constituída por 53 indivíduos. O estudo inclui todos aqueles alunos da instituição que conseguiam realizar a escovagem dentária sozinhos, sem qualquer ajuda. A investigação dividiu-se em 3 fases: na primeira fase foi avaliada a eficácia da escovagem dentária dos utentes sem qualquer instrução por parte do investigador, recorrendo a um revelador de placa bacteriana sem qualquer contraindicação para a saúde do indivíduo; numa segunda etapa foram dadas instruções de técnicas de escovagem com base nos resultados da fase anterior, auxiliando com atividades de motivação para a higiene da cavidade oral; por fim foi realizada uma nova avaliação do índice de placa bacteriana para verificar se houve ou não eficácia na remoção do biofilme dentário. Apesar das limitações físicas e mentais destes pacientes atuarem como um travão para uma boa higiene oral, os resultados são positivos, indicam que se verificou a existência de melhorias significativas no IHO-s após a intervenção. Do primeiro para o segundo momento houve uma diminuição dos valores médios deste índice, ou seja, houve uma melhoria na higiene oral desta população, após a instrução. Conclui-se que é importante para estes pacientes reforçar-se continuamente os hábitos de higiene oral, uma vez que reforça a interiorização do conhecimento, havendo não só melhorias na saúde oral destes indivíduos como melhoria na sua qualidade de vida e na saúde em geral.
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Hydrogen is considered as an appealing alternative to fossil fuels in the pursuit of sustainable, secure and prosperous growth in the UK and abroad. However there exists a persisting bottleneck in the effective storage of hydrogen for mobile applications in order to facilitate a wide implementation of hydrogen fuel cells in the fossil fuel dependent transportation industry. To address this issue, new means of solid state chemical hydrogen storage are proposed in this thesis. This involves the coupling of LiH with three different organic amines: melamine, urea and dicyandiamide. In principle, thermodynamically favourable hydrogen release from these systems proceeds via the deprotonation of the protic N-H moieties by the hydridic metal hydride. Simultaneously hydrogen kinetics is expected to be enhanced over heavier hydrides by incorporating lithium ions in the proposed binary hydrogen storage systems. Whilst the concept has been successfully demonstrated by the results obtained in this work, it was observed that optimising the ball milling conditions is central in promoting hydrogen desorption in the proposed systems. The theoretical amount of 6.97 wt% by dry mass of hydrogen was released when heating a ball milled mixture of LiH and melamine (6:1 stoichiometry) to 320 °C. It was observed that ball milling introduces a disruption in the intermolecular hydrogen bonding network that exists in pristine melamine. This effect extends to a molecular level electron redistribution observed as a function of shifting IR bands. It was postulated that stable phases form during the first stages of dehydrogenation which contain the triazine skeleton. Dehydrogenation of this system yields a solid product Li2NCN, which has been rehydrogenated back to melamine via hydrolysis under weak acidic conditions. On the other hand, the LiH and urea system (4:1 stoichiometry) desorbed approximately 5.8 wt% of hydrogen, from the theoretical capacity of 8.78 wt% (dry mass), by 270 °C accompanied by undesirable ammonia and trace amount of water release. The thermal dehydrogenation proceeds via the formation of Li(HN(CO)NH2) at 104.5 °C; which then decomposes to LiOCN and unidentified phases containing C-N moieties by 230 °C. The final products are Li2NCN and Li2O (270 °C) with LiCN and Li2CO3 also detected under certain conditions. It was observed that ball milling can effectively supress ammonia formation. Furthermore results obtained from energetic ball milling experiments have indicated that the barrier to full dehydrogenation between LiH and urea is principally kinetic. Finally the dehydrogenation reaction between LiH and dicyandiamide system (4:1 stoichiometry) occurs through two distinct pathways dependent on the ball milling conditions. When ball milled at 450 RPM for 1 h, dehydrogenation proceeds alongside dicyandiamide condensation by 400 °C whilst at a slower milling speed of 400 RPM for 6h, decomposition occurs via a rapid gas desorption (H2 and NH3) at 85 °C accompanied by sample foaming. The reactant dicyandiamide can be generated by hydrolysis using the product Li2NCN.
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A partir de la dinámica evolutiva de la economía de las Tecnologías de la Información y las Comunicaciones y el establecimiento de estándares mínimos de velocidad en distintos contextos regulatorios a nivel mundial, en particular en Colombia, en el presente artículo se presentan diversas aproximaciones empíricas para evaluar los efectos reales que conlleva el establecimiento de definiciones de servicios de banda ancha en el mercado de Internet fijo. Con base en los datos disponibles para Colombia sobre los planes de servicios de Internet fijo ofrecidos durante el periodo 2006-2012, se estima para los segmentos residencial y corporativo el proceso de difusión logístico modificado y el modelo de interacción estratégica para identificar los impactos generados sobre la masificación del servicio a nivel municipal y sobre las decisiones estratégicas que adoptan los operadores, respectivamente. Respecto a los resultados, se encuentra, por una parte, que las dos medidas regulatorias establecidas en Colombia en 2008 y 2010 presentan efectos significativos y positivos sobre el desplazamiento y el crecimiento de los procesos de difusión a nivel municipal. Por otra parte, se observa sustituibilidad estratégica en las decisiones de oferta de velocidad de descarga por parte de los operadores corporativos mientras que, a partir del análisis de distanciamiento de la velocidad ofrecida respecto al estándar mínimo de banda ancha, se demuestra que los proveedores de servicios residenciales tienden a agrupar sus decisiones de velocidad alrededor de los niveles establecidos por regulación.
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Este estudio de caso analiza las razones por las cuales México adelantó una reforma constitucional en materia energética en 2013, y el interés que tuvo Estados Unidos en esta, puesto que se destaca la intención del gobierno estadounidense de convertir a América del Norte en una región más sólida. Es así como se exponen las razones por las cuales México decide reformar su constitución y por esa vía tener un impacto directo en Petróleos Mexicanos (Pemex), la cual es la mayor compañía del país, encargada de adelantar los procesos de exploración y explotación de hidrocarburos. Asimismo, se explica el interés de Estados Unidos en el tema del intercambio de hidrocarburos, ya que es primordial para lograr la seguridad energética en Norteamérica, una región donde se está realizando extracción de gas y petróleo a través del fracking, un método no convencional, que ha propiciado un nuevo panorama en los recursos energéticos.
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Para se efectuar a investigação sobre a joalharia portuguesa contemporânea, a partir de 1950, procedeu-se ao seu enquadramento histórico e geográfico. À semelhança do que se verificava resto do mundo, constata-se uma interdisciplinaridade com as restantes artes plásticas (em especial com o design). E consequente alteração das formas, materiais e técnicas anteriormente usadas. Também ao nível da função da jóia se observaram alterações. Foi, então, estudada a relação da joia com o corpo. Portugal conta com um conjunto de artistas joalheiros em plena produção. Existem estruturas de ensino e profissionais, sem, contudo, haver um museu de joalharia contemporânea. Mesmo assim, é de notar o elevado número de exposições e projectos relacionados com esta temática. Neste panorama, surge uma joalharia contemporânea liberta de uma identidade, que permite que o trabalho de cada artista seja singular, sem obedecer a regras limitativas ou castradoras da criatividade. /ABSTRACT: It was during the 50s that in order to carry out the research on the contemporary portuguese jewellery, one had to establish its historical and geographical approach. As it happened in the rest of the world, one may say there was an interdisciplinary with the other fine arts (specially with the design) and the consequent change in the shapes, materials and techniques previously used. The jewel was not an exception to these changes as far its function is concerned. Due to these factors, the relationship between the jewel and the body started to be studied. Nowadays Portugal counts a set of jewelers in full production. There are specialized schools in this area as well as professionals although there isn't a museum of contemporary jeweler. ln spite of this, a huge number of exhibitions and projects concerning this area, take place in Portugal. Taking all these aspects into consideration, a free contemporary jewelry is emerging, allowing the work of each artist may be unique without obeying to any strict or limitative rules that could work as a barrier to their creativity.
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In digital markets personal information is pervasively collected by firms. In the first chapter I study data ownership and product customization when there is exclusive access to non rival but excludable data about consumer preferences. I show that an incumbent firm does not have an incentive to sell an exclusively held dataset with a rival firm, but instead it has an incentive to trade a customizing technology with the other firm. In the second chapter I investigate the effects of consumer information on the intensity of competition. In a two dimensional model of product differentiation, firms use information on preferences to practice price discrimination. I contrast a full privacy and a no privacy benchmark with a regime in which firms are able to target consumers only partially. When data is partially informative, firms are always better-off with price discrimination and an exclusive access to user data is not necessarily a competition policy concern. From a consumer protection perspective, the policy recommendation is that the regulator should promote either no privacy or full privacy. In the third chapter I introduce a data broker that observes either only one or both dimensions of consumer information and sells this data to competing firms for price discrimination purposes. When the seller exogenously holds a partially informative dataset, an exclusive allocation arises. Instead, when the dataset held is fully informative, the data broker trades information non exclusively but each competitor acquires consumer data on a different dimension. When data collection is made endogenous, non exclusivity is robust if collection costs are not too high. The competition policy suggestion is that exclusivity should not be banned per se, but it is data differentiation in equilibrium that rises market power in competitive markets. Upstream competition is sufficient to ensure that both firms get access to consumer information.
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Although there is broad agreement on the need to transition to a fairer agro-food system, consumer potential in shaping a fair food system has often been overlooked. There is no unique definition of the concept of fairness from the consumer’s perspective. In addition, there are no scales in the academic literature that address fairness in its broad sense, as the existing scales focus on specific and limited aspects that provide a partial picture of the concept. Lack of a true and trustworthy measurement of the notion has been a significant barrier to the knowledge of fairness in agro-food systems from the individual-differences perspective. The individual-differences perspective helps explain why some individuals are more likely than others to put emphasis on the extent to which agro-food chains are fair. Individual consumer perception of an ethical problem is followed by the perception of various alternatives that might lead to a solution. Therefore, the current research intends to make two significant contributions by resolving these constraints. First, advance the literature by providing a new viewpoint to understand fairness in the agro-food chain. Indeed, the research provides a comprehensive conceptualisation of fairness that embraces different aspects of fairness and describes the concept in all its facets and nuances. Second, the research provides a valid, reliable, and invariant measurement of the individual disposition toward fairness in agro-food chains by rooting the items in the theoretical underpinnings of the fairness literature. Overall, this research provides a comprehensive suite of approaches and tools to enhance the resilience, integrity and sustainability of agro-food chains.
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Miniaturized flying robotic platforms, called nano-drones, have the potential to revolutionize the autonomous robots industry sector thanks to their very small form factor. The nano-drones’ limited payload only allows for a sub-100mW microcontroller unit for the on-board computations. Therefore, traditional computer vision and control algorithms are too computationally expensive to be executed on board these palm-sized robots, and we are forced to rely on artificial intelligence to trade off accuracy in favor of lightweight pipelines for autonomous tasks. However, relying on deep learning exposes us to the problem of generalization since the deployment scenario of a convolutional neural network (CNN) is often composed by different visual cues and different features from those learned during training, leading to poor inference performances. Our objective is to develop and deploy and adaptation algorithm, based on the concept of latent replays, that would allow us to fine-tune a CNN to work in new and diverse deployment scenarios. To do so we start from an existing model for visual human pose estimation, called PULPFrontnet, which is used to identify the pose of a human subject in space through its 4 output variables, and we present the design of our novel adaptation algorithm, which features automatic data gathering and labeling and on-device deployment. We therefore showcase the ability of our algorithm to adapt PULP-Frontnet to new deployment scenarios, improving the R2 scores of the four network outputs, with respect to an unknown environment, from approximately [−0.2, 0.4, 0.0,−0.7] to [0.25, 0.45, 0.2, 0.1]. Finally we demonstrate how it is possible to fine-tune our neural network in real time (i.e., under 76 seconds), using the target parallel ultra-low power GAP 8 System-on-Chip on board the nano-drone, and we show how all adaptation operations can take place using less than 2mWh of energy, a small fraction of the available battery power.
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The animal gut plays a central role in tackling two common ecological challenges, nutrient shortage and food-borne parasites, the former by efficient digestion and nutrient absorption, the latter by acting as an immune organ and a barrier. It remains unknown whether these functions can be independently optimised by evolution, or whether they interfere with each other. We report that Drosophila melanogaster populations adapted during 160 generations of experimental evolution to chronic larval malnutrition became more susceptible to intestinal infection with the opportunistic bacterial pathogen Pseudomonas entomophila. However, they do not show suppressed immune response or higher bacterial loads. Rather, their increased susceptibility to P. entomophila is largely mediated by an elevated predisposition to loss of intestinal barrier integrity upon infection. These results may reflect a trade-off between the efficiency of nutrient extraction from poor food and the protective function of the gut, in particular its tolerance to pathogen-induced damage.
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In 2003 the Restriction of Hazardous Substances (RoHS) was established in the EU, which limited the trade of machinery, electrical and electronic equipment that have at least one of the substances considered hazardous under RoHS directive. Since countries trading with the EU must comply with this new regulation, it is expected a decrease in value of imports to the EU. In this paper, it is followed the procedures used in Heckman (1979), as well as the extended procedure suggested by Helpman, Melitz, and Rubinstein (2008) to ascertain the effects on the persistence of trade and values of trade.
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Reproduced from typewritten copy