994 resultados para public display


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Combinatorial Optimization Problems occur in a wide variety of contexts and generally are NP-hard problems. At a corporate level solving this problems is of great importance since they contribute to the optimization of operational costs. In this thesis we propose to solve the Public Transport Bus Assignment problem considering an heterogeneous fleet and line exchanges, a variant of the Multi-Depot Vehicle Scheduling Problem in which additional constraints are enforced to model a real life scenario. The number of constraints involved and the large number of variables makes impracticable solving to optimality using complete search techniques. Therefore, we explore metaheuristics, that sacrifice optimality to produce solutions in feasible time. More concretely, we focus on the development of algorithms based on a sophisticated metaheuristic, Ant-Colony Optimization (ACO), which is based on a stochastic learning mechanism. For complex problems with a considerable number of constraints, sophisticated metaheuristics may fail to produce quality solutions in a reasonable amount of time. Thus, we developed parallel shared-memory (SM) synchronous ACO algorithms, however, synchronism originates the straggler problem. Therefore, we proposed three SM asynchronous algorithms that break the original algorithm semantics and differ on the degree of concurrency allowed while manipulating the learned information. Our results show that our sequential ACO algorithms produced better solutions than a Restarts metaheuristic, the ACO algorithms were able to learn and better solutions were achieved by increasing the amount of cooperation (number of search agents). Regarding parallel algorithms, our asynchronous ACO algorithms outperformed synchronous ones in terms of speedup and solution quality, achieving speedups of 17.6x. The cooperation scheme imposed by asynchronism also achieved a better learning rate than the original one.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Abstract: INTRODUCTION: Few studies have addressed the primary characteristics of patients infected with hepatitis B virus (HBV) in the general population, especially those living in small- and medium-sized cities in Brazil. We aimed to determine the clinical, demographic, and epidemiologic characteristics of patients diagnosed with HBV who were followed up at an infectious diseases clinic of a public hospital in State of São Paulo, Brazil. METHODS: Medical records of patients aged >18 years and diagnosed with HBV infection between January 2000 and December 2013 were reviewed. RESULTS: Seventy-five patients were enrolled with male-female main infection-associated risk factors; 9 (12%) were co-infected with human immunodeficiency virus (HIV), 5 (6.7%) with hepatitis C virus (HCV), and 3 (4%) were co-infected with both HIV and HCV. Antiviral HBV therapy was applied in 21 (28%) patients and tenofovir monotherapy was the most prescribed medication. After approximately 2 years of antiviral treatment, the HBV-DNA viral load was undetectable in 12 (92.3%) patients and lower levels of alanine aminotransferase were found in these patients. CONCLUSIONS: Over a 13-year interval, very few individuals infected with HBV were identified, highlighting the barriers for caring for patients with HBV in developing countries. New measures need to be implemented to complement curative practices.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Notch is a conserved signalling pathway, which plays a crucial role in a multiple cellular processes such as stem cell self-renewal, cell division, proliferation and apoptosis. In mammalian, four Notch receptors and five ligands are described, where interaction is achieved through their extracellular domains, leading to a transcription activation of different target genes. Increased expression of Notch ligands has been detected in several types of cancer, including breast cancer suggesting that these proteins represent possible therapeutic targets. The goal of this work was to generate quality protein targets and, by phage display technology, select function-blocking antibodies specific for Notch ligands. Phage display is a powerful technique that allows the generation of highly specific antibodies to be used for therapeutics, and it has also proved to be a reliable approach in identifying and validating new cancer-related targets. Also, we aimed at solving the tri-dimensional structure of the Notch ligands alone and in complex with selected antibodies. In this work, the initial phase focused on the optimization of the expression and purification of a human Delta-like 1 ligand mutant construct (hDLL1-DE3), by refolding from E. coli inclusion bodies. To confirm the biological activity of the produced recombinant protein cellular functional studies were performed, revealing that treatment with hDLL1-DE3 protein led to a modulation of Notch target genes. In a second stage of this study, Antibody fragments (Fabs) specific for hDLL1-DE3 were generated by phage display, using the produced protein as target, in which one good Fab candidate was selected to determine the best expression conditions. In parallel, multiple crystallization conditions were tested with hDLL1-DE3, but so far none led to positive results.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The main purpose of this case-study is to analyse CTT’s privatisation process, a previously Government-owned firm, which went public in 2013, under the terms of the adjustment program agreed between Portugal, the European institutions (ECB and European Commission) and the IMF. The emphasis will be placed on the IPO process, but also on the company itself (its history, current situation and prospects for its new phase, as a publicly listed company). This piece of work aims to evaluate the different alternatives for the privatisation of the company along with the respective implications, as well as the outcome of the actual decision taken by the Portuguese Government. One key aspect of the case is also to understand the importance that the privatisation of the Royal Mail, which can be seen as a peer of the Portuguese company, in the unfolding of the process and in the choice of the privatisation model. The case intends to show how the British process influenced the subsequent option of the Portuguese entities to sell CTT through an IPO, instead of a trade sale. All in all, the overall objective of this case-study is to analyse CTT’s successful sale process, which created the first Portuguese company with 100% free-float. 3 On the last days of November 2013, Steven Bernstein was staring at the window of his office overlooking downtown Manhattan, not even noticing the intense rain that was pouring down. As senior manager at ABC Fund, a pension fund responsible for managing more than 800 million dollars, his thoughts were focused on a very important decision that ABC Fund would have to make in just a matter of days. The American pension fund was considering whether or not to invest in the upcoming Initial Public Offering of CTT- Correios de Portugal, the Government-owned Portuguese mail company. Is this investment opportunity in accordance with the risk profile of a pension fund? Is it a wise decision to acquire shares in a Portuguese company when the country is at the centre of the European Sovereign debt crisis, going through a very demanding economic adjustment program imposed by its bail-out creditors? Would the creation of Portugal's Postal Bank make CTT a sure bet today when its price does not fully reflect the future benefits from entering financial services? Those were some of the questions that were constantly in Mr. Bernstein’s mind over the last couple of days and he was struggling to find the answers…

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In museum studies and history of art, what happens behind the scenes of museums stays relatively unseen and unspoken about. In the arts, generally speaking, what is dismissed as irrelevant (e.g. the realm of practices) is deliberately detached from what is thought to really matter; theory, discourse, content and meaning. Up till recently, backstage activities such as conservation practices are merely discussed among specialists and museum professionals. Only the outcomes of these discussions are sometimes – if at all – explicitly communicated to a larger public. Studies into the practices of contemporary art conservation however show that practices behind the scenes play an important role in the perpetuation of these artworks. What happens behind the scenes in terms of conservation has, in several ways, important effects on the ongoing life of these artworks in a museum context. Conservation practices, I argue, should therefore become a necessary part of museum studies and history of art. How can the working practices of conservators become more visible and transparent to a diversity of audiences, including researchers? And what does this mean in terms of research methodology?

Relevância:

20.00% 20.00%

Publicador:

Resumo:

O OPA da Embaixada dos EUA é o departamento responsável por todos os eventos e relações públicas da Embaixada, assim como todos os programas de intercâmbio educacionais e culturais, com o âmbito de promover a política externa americana, assim como os seus valores. O departamento é principal ponto de contato com os meios de comunicação, organizações e pessoas individuais que queiram obter informações sobre os EUA. Além das tarefas desenvolvidas, enquanto estagiária, no âmbito da linha de trabalho do OPA, o presente relatório contém uma contextualização e enquadramento histórico sobre a PD. A PD tem como objetivo promover os interesses nacionais e a política externa, além de informar e influenciar os públicos estrangeiros sobre a sociedade norte-americana e o Governo dos EUA. Todo o trabalho desempenhado no OPA está intrinsecamente ligado à PD e por isso este relatório está dividido em duas partes: a descrição das minhas atividades no departamento e o trabalho de investigação sobre a PD.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Degeneration (WetAMD) and Diabetic Macular Edema (DME) patients’ access to treatment in public hospitals, by identifying bottlenecks and stress points that prevent timely and adequate care to patients who suffer from a degenerative disease, and consequently for whom the lack of access to treatment can have disastrous consequences. Considering the specificity and degenerative traits of these conditions, the long queues for specialty appointments in public hospitals are a significant threat to patients’ health, as the disease may be misdiagnosed and or progress significantly, causing unnecessary permanent and non-reversible loss in visual acuity. Therefore optimizing the patient journey will increase patients’ access to adequate treatment, and prevent avoidable progress of a degenerative condition which causes permanent and non-reversible blindness. Following the investigation which supports this thesis, the patient journey was broken down into its different phases, so that key issues could be identified, and referred back to the main stress points highlighted during the interviews with physicians and administrators. Finally results were scrutinized and systematized, and a set of action points was proposed, considering what may cause major impact and is actually feasible to implement.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Delay Tolerant Network (DTN) is a communication architecture enabling connectivity in a topology with unregular end-to-end network connection. DTN enables communication in environments with cross-connectivity, large delays and delivery time variations, and a high error rate. DTN can be used in vehicular networks where public transport get involved. This research aims to analyze the role of public transit as a DTN routing infrastructure. The impact of using public transit as a relay router is investigated by referencing the network performance, defined by its delivery ratio, average delay and overhead. The results show that public transit can be used as a backbone for DTN in an urban scenario using existing protocols. This opens insights for future researches on routing algorithm and protocol design.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Microbiology as a scientific discipline recognised the need to preserve microorganisms for scientific studies establishing from its very beginning research culture collections (CC). Later on, to better serve different scientific fields and bioindustries with the increasing number of strains of scientific, medical, ecological and biotechnological importance public service CC were established with the specific aims to support their user communities. Currently, the more developed public service CC are recognised as microBiological Resources Centres (mBRC). mBRC are considered to be one of the key elements for sustainable international scientific infrastructure, which is necessary to underpin successful delivery of the benefits of biotechnology, whether within the health sector, the industrial sector or other sectors, and in turn ensure that these advances help drive economic growth. In more detail, mBRCs are defined by Organisation for Economic Co-operation and Development (OECD) as service providers and repositories of the living cells, genomes of organisms, and information relating to heredity and functions of biological systems. mBRCs contain collections of culturable organisms (e.g., microorganisms, plant, animal cells), replicable parts of these (e.g. genomes, plasmids, virus, cDNAs), viable but not yet culturable organisms, cells and tissues, as well as database containing molecular, physiological and structural information relevant to these collections and related bioinformatics. Thus mBRCs are fundamental to harnessing and preserving the world’s microbial biodiversity and genetic resources and serve as an essential element of the infrastructure for research and development. mBRCs serve a multitude of functions and assume a range of shapes and forms. Some are large national centres performing a comprehensive role providing access to diverse organisms. Other centres play much narrower, yet important, roles supplying limited but crucial specialised resources. In the era of the knowledge-based bio-economy mBRCs are recognised as vital element to underpinning the biotechnology.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tese de Doutoramento em Ciências da Literatura (área de especialização em Literatura Portuguesa).

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Expanding access to preschool education is a particularly important policy issue in developing countries, where enrollment rates are generally much lower, and where private institutions constitute a much larger share of the formal preschool sector, than in developed countries. This paper examines if an expansion in the supply of public preschool crowds-out private enrollment using rich data for municipalities in Brazil from 2000 to 2006, where federal transfers to local governments change discontinuously with given population thresholds. Results from a regression-discontinuity design reveal that larger federal transfers lead to a significant expansion of local public preschool services, but show no evidence of crowding-out of private enrollment, nor of negative impacts on the quality of private providers. This finding is consistent with a theory in which households differ in willingness-to-pay for preschool services, and private suppliers optimally adjust prices in response to an expansion of lower-quality, free-of-charge public supply. In the context of the model, the absence of crowding-out effects of more public preschool providers can be rationalized by the existence of relatively large differences in willingness-to-pay for preschool services across different demand segments. Our theoretical and empirical findings therefore suggest that in developing country settings characterized by relatively high income inequality, an expansion in public preschool supply will likely significantly increase enrollment among the poorest segments of society, and need not have adverse effects on the quantity or quality of local private supply.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aim of this work was to investigate the effect on a display gamut of varying the optical density and the position of the maximum sensitivity of the cones spectra of anomalous trichromatic observers. The anomalous cone spectral sensitivities were estimated for a set of varying optical density and maximum sensitivity spectra conditions and used to compute the display color gamut. The computed display gamut simulated for normal observers the chro- matic diversity perceived by anomalous observers. It was found that even small variations on the optical density and on the position of the maximum sensitivity spectra have an impact on the simulations of the display gamut for anomalous observers. It was also found that simulations for deuteroanomalous observers are the ones with greater impact if the estimation of the corresponding color display gamut is not carefully adjusted for the observer.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

OBJECTIVE The aim of this study was to compare the performance of the current conventional Pap smear with liquid-based cytology (LBC) preparations. STUDY DESIGN Women routinely undergoing their cytopathological and histopathological examinations at Fundação Oncocentro de São Paulo (FOSP) were recruited for LBC. Conventional smears were analyzed from women from other areas of the State of São Paulo with similar sociodemographic characteristics. RESULTS A total of 218,594 cases were analyzed, consisting of 206,999 conventional smears and 11,595 LBC. Among the conventional smears, 3.0% were of unsatisfactory preparation; conversely, unsatisfactory LBC preparations accounted for 0.3%. The ASC-H (atypical squamous cells - cannot exclude high-grade squamous intraepithelial lesion) frequency did not demonstrate any differences between the two methods. In contrast, the incidence of ASC-US (atypical squamous cells of undetermined significance) was almost twice as frequent between LBC and conventional smears, at 2.9 versus 1.6%, respectively. An equal percentage of high-grade squamous intraepithelial lesions were observed for the two methods, but not for low-grade squamous intraepithelial lesions, which were more significantly observed in LBC preparations than in conventional smears (2.2 vs. 0.7%). The index of positivity was importantly enhanced from 3.0% (conventional smears) to 5.7% (LBC). CONCLUSIONS LBC performed better than conventional smears, and we are truly confident that LBC can improve public health strategies aimed at reducing cervical lesions through prevention programs.