Bitocast: a hybrid BitTorrent and IP Multicast content distribution solution

Dissertação apresentada para obtenção do Grau de Mestre em Informática, pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia

Species and biotype distribution of thermotolerant Campylobacters in animal reservoirs in Southern Chile

The prevalence of thermotolerant Campylobacters in mammals and birds from Southern Chile was determined. Campylobacters were isolated from 46.3% of the animals studied being C. jejuni biotipe 1 the most frequent (25.7%) followed by C. coli (17.4%) and C. jejuni biotipe 2 (3.2%).

18F-FDG measurement in primary lung cancer: SUV normalization to different distribution volumes

Introduction: Standard Uptake Value (SUV) is a measurement of the uptake in a tumour normalized on the basis of a distribution volume and is used to quantify 18F-Fluorodeoxiglucose (FDG) uptake in tumors, such as primary lung tumor. Several sources of error can affect its accuracy. Normalization can be based on body weight, body surface area (BSA) and lean body mass (LBM). The aim of this study is to compare the influence of 3 normalization volumes in the calculation of SUV: body weight (SUVW), BSA (SUVBSA) and LBM (SUVLBM), with and without glucose correction, in patients with known primary lung tumor. The correlation between SUV and weight, height, blood glucose level, injected activity and time between injection and image acquisition is evaluated. Methods: Sample included 30 subjects (8 female and 22 male) with primary lung tumor, with clinical indication for 18F-FDG Positron Emission Tomography (PET). Images were acquired on a Siemens Biography according to the department’s protocol. Maximum pixel SUVW was obtained for abnormal uptake focus through semiautomatic VOI with Quantification 3D isocontour (threshold 2.5). The concentration of radioactivity (kBq/ml) was obtained from SUVW, SUVBSA, SUVLBM and the glucose corrected SUV were mathematically obtained. Results: Statistically significant differences between SUVW, SUVBSA and SUVLBM and between SUVWgluc, SUVBSAgluc and SUVLBMgluc were observed (p=0.000<0.05). The blood glucose level showed significant positive correlations with SUVW (r=0.371; p=0.043) and SUVLBM (r=0.389; p=0.034). SUVBSA showed independence of variations with the blood glucose level. Conclusion: The measurement of a radiopharmaceutical tumor uptake normalized on the basis of different distribution volumes is still variable. Further investigation on this subject is recommended.

Zonal distribution of gold and platinium group elements in the Mondunguara deposits Mozambique

The Mondunguara copper mines are situated in mountainous terrain in west-central Mozambique. The mineralization consists of chalcopyrite, pyrrhotite, common pcntlandite, cobaltpentlandite, pyrite and several minor oxides and sulphides in tabular ore bodies deeping steep to the north. Gold was known to occur in small quantities but no systematic sampling and analysis for precious clements was ever done. Mineralogical and geological evidence has shown that the ores are magmatic in origin and were derived from gabbro-peridotitic magma dykes saturated in sulphides when intruded. The ore bodies show a clear zonation. Platinum group elements as well as pure gold are associated with high temperature hexagonal pyrrhotite. This pyrrhotite being of no use is generally discarded to the tailing dumps. Late hydrothermal phases are enriched in native silver, silver tellurides as well as electrum.

Magnetic flux density distribution in the air gap of a ferromagnetic core with superconducting blocks: three-dimensional analysis and experimental NMR results

The design of magnetic cores can be carried out by taking into account the optimization of different parameters in accordance with the application requirements. Considering the specifications of the fast field cycling nuclear magnetic resonance (FFC-NMR) technique, the magnetic flux density distribution, at the sample insertion volume, is one of the core parameters that needs to be evaluated. Recently, it has been shown that the FFC-NMR magnets can be built on the basis of solenoid coils with ferromagnetic cores. Since this type of apparatus requires magnets with high magnetic flux density uniformity, a new type of magnet using a ferromagnetic core, copper coils, and superconducting blocks was designed with improved magnetic flux density distribution. In this paper, the designing aspects of the magnet are described and discussed with emphasis on the improvement of the magnetic flux density homogeneity (Delta B/B-0) in the air gap. The magnetic flux density distribution is analyzed based on 3-D simulations and NMR experimental results.

Optimal brake specific fuel consumption trajectory for stand-alone variable speed Diesel Gen-Set

Energy efficiency plays an important role to the CO2 emissions reduction, combating climate change and improving the competitiveness of the economy. The problem presented here is related to the use of stand-alone diesel gen-sets and its high specific fuel consumptions when operates at low loads. The variable speed gen-set concept is explained as an energy-saving solution to improve this system efficiency. This paper details how an optimum fuel consumption trajectory based on experimentally Diesel engine power map is obtained.

Angiostrongylus costaricensis: first record of its occurrence in the State of Espirito Santo, Brazil, and a review of its geographic distribution

Abdominal angiostrongyliasis is a parasitic disease caused by Angiostrongylus costaricensis, a metastrongylid nematode with wide geographic distribution, occurring from the United States to Argentina. In Brazil, the disease has been reported from the States of Rio Grande do Sul, Santa Catarina, Paraná, São Paulo, Federal District of Brasilia and Minas Gerais. We report here a case of abdominal angiostrongyliasis in a 9-year-old girl, from Itatiba, State of Espirito Santo, Brazil, submitted to exploratory laparotomy for acute abdomen. Extensive inflammatory lesions of terminal ileum and cecum, with perforations of the first, were present, and ileocecal resection was performed. The pathological picture was characterized by transmural inflammatory granulomatous reaction, extensive eosinophilic infiltration, eosinophilic vasculitis and the presence of worms within a mesenteric artery branch, with histological features of metastrongylid nematodes. This case report contributes to a better knowledge of the geographic distribution of this parasite in Brazil, suggesting that abdominal angiostrongyliasis may represent a disease of medical importance, more than a rarity of academic interest.

Scorpion sting epidemiology in Montes municipality of the State of Sucre, Venezuela: geographic distribution

Scorpion stings were surveyed in the Montes Municipality of the State of Sucre, Venezuela, aiming to extend the information on these poisonous accidents by characterizing their geographic distribution. From 1980 to 1990, 184 cases of scorpion stings were recorded with an incidence rate of 38.6 cases per 10,000 inhabitants. The locality of San Fernando presented the highest incidence (68.3(0)/000) of poisonous accidents. The highest percentages of severe cases were recorded in the towns of Arenas (27%), San Lorenzo (21%), and Cocollar (19%), which are located at the foot of the Turimiquire Mountains. This region is a dispersion area of scorpions of the Tityus genus. Our results show that this region of the State of Sucre is endemic for scorpion stings which are an important public health problem.

Anemia de células falciformes na idade pediátrica : contribuição para o estudo das suas principais complicações e indicadores de prognóstico

RESMO: Introdução: A anemia de células falciformes doença hereditária, com repercussão multi-orgânica, tem grande variabilidade na sua expressão clínica. Daí o interesse do estudo de indicadores de prognóstico. A investigação realizada foi precedida de um resumo histórico incidindo sobre a compreensão de aspectos fundamentais da doença ao longo dos tempos. Na primeira parte do estudo e após revisão bibliográfica, foram referidos dados da fisiopatologia como base para os estudos que integram a presente dissertação. Abordou-se o estado da arte relativamente às complicações, aos indicadores de prognóstico e à terapêutica utilizada. Objectivos: Constituíram objectivos deste estudo realizado numa amostra populacional representativa: identificar as lesões a nível dos sistemas cardio-respiratório e nervoso central, avaliando-se as respectivas repercussões; avaliar a presença de indicadores de prognóstico entre as variáveis seleccionadas; estudar a eficácia e toxicidade da HU nos doentes com as formas graves da ACF. Para a prossecução destes objectivos foram delineados para além do estudo global três estudos específicos: Estudo 1- repercussão no sistema cardio-respiratório; Estudo 2- repercussão no sistema nervoso central; Estudo 3- terapêutica com hidroxiureia. Doentes e métodos: Procedeu-se a um estudo prospectivo e multi-institucional durante um período de três anos tendo-se seleccionado para a amostra, e de acordo com critérios pré-definidos, 30 doentes com ACF na fase estável da doença, com idades compreendidas entre os sete e os 18 anos, todos de origem africana à excepção de um caucasiano. O diagnóstico baseou-se em técnicas de electroforese e estudo molecular que definiu o genotipo da doença e a presença da delecção da -talassémia assim como os haplotipos da amostra populacional. Foram utilizadas diferentes metodologias para avaliar a existência de lesão pulmonar e cerebral. Através do estudo estatístico foram seleccionadas diversas variáveis como hipotéticos indicadores de prognóstico. Estudo 1. Para determinar a existência de lesão a nível pulmonar usaram-se duas metodologias diferentes, a avaliação da função pulmonar com estudo da saturação da Hb em O2 no sangue arterial e a tomografia computadorizada de alta resolução. Estudou-se também a possível disfunção cardíaca como repercussão da lesão pulmonar, através do ecocardiograma, e os indicadores de prognóstico com significado estatístico para a lesão encontrada. Estudo 2. O desenho deste estudo foi sobreponível ao anterior, mas com metodologia adequada para o SNC. Procedeu-se ao estudo das lesões cerebrais por meio de exames imagiológicos, (RMN-CE e DTC) e de testes psicológicos. Correlacionaram-se as três metodologias utilizadas e a importância de cada uma para a decisão de atitudes terapêuticas preventivas. Estudo 3. Consistiu num estudo aberto prospectivo não controlado com nove crianças e adolescentes com formas graves de ACF, com o objectivo de avaliar a eficácia da terapêutica com hidroxiureia, durante um período de 24 meses. Todos os doentes completaram no mínimo 15 meses de terapêutica, com uma dose final média de 194 mg/K/dia. Resultados globais: Durante o período anterior à investigação caracterizou-se a amostra populacional estudada quanto ao fenotipo genético, clínico e hematológico de acordo com os critérios utilizados por outros investigadores. Verificou-se: predomínio do haplotipo Bantu na forma homozigótica em 53% dos doentes; número total de EVO ≥3/ano em 87,5% dos doentes; crises de sequestração em 18,75%; dactilites no primeiro ano de vida em 31,2%; quadro de sépsis grave apenas num doente; crises de hiper-hemólise em 50%; e STA em 59,38% dos doentes. Quanto ao fenotipo hematológico evidenciaram-se como factores de risco reticulocitose (13,1x103/l) e hiperbilirrubinémia (2,5 mg/dl) e como factores de bom prognóstico a presença de delecção de um gene da -talassémia em 46,9% dos doentes e valor médio de Hb 8,1 g/dl. Resultados dos estudos parcelares: Estudo 1. Deste estudo infere-se que a DPR ligeira foi diagnosticada em 70% dos doentes, uma vez que as alterações da difusão não foram estatisticamente significativas, o estudo dos gases no sangue não evidenciaram resultados anormais e a TCAR evidenciou alterações em 43,3% dos doentes. Apenas num doente se verificou doença pulmonar obstrutiva relacionada com maior número da STA.O estudo da disfunção cardíaca encontrada em 86,7% dos doentes não reflecte a repercussão da DPR a nível cardíaco, podendo estar associada às alterações fisiopatológicas da própria anemia crónica. Encontraram-se indicadores de prognóstico hematológicos e clínicos. Entre os primeiros, valores de Hb ≥8,5 g/dl e de HbF ≥13% foram considerados indicadores de bom prognóstico para a lesão pulmonar. Em relação aos parâmetros clínicos, as STA não foram consideradas indicadoras de prognóstico para a DPR ao contrário do que se verificou com o número de EVO. Pela análise dos parâmetros genéticos e socio-económicos provou-se a ausência de relação estatisticamente significativa com lesão pulmonar. Estudo 2. Pela RMN-CE foram diagnosticados ES em 33,3% com uma localização preferencial na substância branca profunda em 26,6% dos doentes. Relativamente aos parâmetros hematológicos seleccionados, o valor médio da HbF 8,6% constituíu um indicador de bom prognóstico para o aparecimento de ES, enquanto o valor médio de leucócitos 12.39x103/μl foi considerado um indicador de mau prognóstico. No estudo do DTC apenas um doente apresentou aumento da velocidade do fluxo cerebral na ACM igual a 196 cm/segundos, associado a vasculopatia grave. Os testes psicológicos alterados em 80% dos doentes mostraram ser o método mais sensível para detectar alterações do neurodesenvolvimento, mas sem correlação com os ES em 10% dos doentes. Realça-se a baixa percentagem de DTC patológicos encontrados neste estudo em relação ao número elevado de ES e de testes psicológicos alterados, não se verificando concordância entre os três exames. Dos indicadores de prognóstico estudados a -talassémia foi considerada um factor de protecção para o coeficiente de inteligência da escala de Wechsler. Em relação a parâmetros clínicos estudados os doentes com maior número de EVO, tem em média valores inferiores nos testes psicológicos. Estudo 3. Neste estudo verificou-se que o valor médio da HbF aumentou significativamente de 7,0±4% para 13,7±5,3% (p=0,028) ao fim de 15 meses de terapêutica com hidroxiureia. Clinicamente todos os doentes responderam significativamente com uma redução de 80% no número de EVO, 69% no número de internamentos, 76% no número de dias de hospitalização e 67% no número de transfusões. Deste modo comprovou-se não só a eficácia desta terapêutica neste grupo pediátrico como também a falta de efeitos secundários significativos. Considera-se a necessidade de estudos mais prolongados e em grande séries, para com segurança se usar a HU antes que a lesão orgânica se estabeleça, portanto logo nos primeiros anos de vida. Conclusão: Na amostra populacional estudada foram evidenciadas lesões pulmonares e cerebrais na grande maioria dos doentes que condicionaram a sua qualidade de vida. Foram identificados indicadores de prognóstico que poderão eventualmente ditar medidas terapêuticas precoces com o objectivo de diminuir a morbilidade e a mortalidade neste grupo etário. Demonstrou-se que a terapêutica com a HU foi eficaz e bem tolerada----------ABSTRACT: Background: Sickle cell anemia (SCA), a hereditary disease characterized by pain and lifetime multi-organic lesion, is a challenge for all that work with carriers of this disease. The clinical expression variability of SCA is a constant reality and a problem to be solved in the current world of investigation, for which the knowledge of prognostic indicators responsible for the different aspects of clinical evolution diversity wiil be an added value. The study is preceded by a historical summary of the most important factors in the evolution of SCA, which are in themselves, an incentive for future research. In the first part of the study, after an extensive bibliographical revision, physiopathology data is referred to in general and specifically regarding the target organs, that constituted the base for the studies presented in the dissertation. The state of the art for the complications to be studied, the choice of prognostic indicators and the therapeutics application, were approached for the renewed interest in the theme. Aims: In regard to the investigation, the objective was to study the lesions in the most affected organs of a chosen pediatric group, to investigate prognostic indicators for lung and cerebral lesions and to evaluate the protective effect of hydroxyurea in children with severe outcomes. Patients and methods: A prospective and multi-institutional study was carried out during a three-year period, February 1998 to March 2001, with children and adolescents followed up at a Immunohematology Outpatient Clinic of Dona Estefânia's Hospital, Lisbon. Based in predefined criteria, 30 children with SCA were selected in a stable phase of the disease, aged from seven to 18 years old, all of whom were of African origin with exception of one who was Caucasian. The diagnosis was based on electrophoresis techniques and molecular study that allowed to define the genotype, the presence of deletional alpha-thalassemia as well as haplotypes in the population. Different methodologies were used to evaluate the existence of lung and cerebral lesion. Statistical study of the different variables selected the prognostic indicators. In Study 1, to determine the existence of lung lesion two different methodologies were used: pulmonar function study with arterial blood gases determination; and high resolution computerized tomography. Heart dysfunction as a repercussion of lung lesion was also studied through echocardiography, and prognostic indicators were statistically significant for lesions found. The design of Study 2 was similar to Study 1, but with the appropriate methodology for CNS. After neurological examination, which was normal in all patients (control group), cerebral lesions were studied with imagiologic exams (MRN-CE and TCD) and psychological tests. These three methodologies were correlated and the importance of each one in the decision of the therapeutic profilactic attitudes. Study 3 consisted of a controlled prospective open study in children with severe forms of SCA, with the aim of the evaluating therapeutic effectiveness of hydroxyurea, during a period of 24 months. Results: In the global overall study preceding the Studies 1,2 and 3, there were a prevalence of haplotype Bantu (53%) and other risk factors, namely the number of VOC (87,5%), sequestration crisis (18,75%), dactilytis in first year of life(31,2%), hyperhemolysis crisis (50%) and ATC in more than half of the patients (59,38%). This group of bad prognostic indicators, associated with the population of the lower class according to the Graffar scale, demonstrates the importance of primary health care services, information provided to the children and their relatives, as well as the interest in prophylactic therapeutics, specific screening and prenatal diagnosis. Study 1. It was evident from this study that slight RPD was diagnosed in 70% of the patients, because alterations of the diffusion had no statistical significance and arterial blood gases determinations were normal. Only one patient had restrictive lung disease related with numerous ACS. However ACS was not considered a prognostic indicator for RPD, contrary to the number of EVO. HRTC revealed discreet fibrotic lines that could be related with slight RPD, but the lack of correlation of these two exams (33%) supports the value of lung function tests for precocious diagnosis of RPD. Heart dysfunction was found in 86,7% of patients, does not reflect the repercussion of RPD, but with the physiopathology of chronic anemia. Hematologic and clinical prognostic indicators were found. Good prognostic indicators for the non-evolution of RPD with average Hb values of ≥ 8,5 g/dl and average HbF values of ≥13%, respectively. The genetic and social-economic factors had no statistical significance; nevertheless, they were more prevalent among Bantu haplotype (53,3%) in patients with RPD. Study 2. RMN-CE detected SI in 33,3% of the patients, with preferential location in deep white substance in 26,6% and in front lobe in 20%. This distribution can be related to structural aspects of the brain and with the high sensibility of this organ to hypoxia. From the hematological parameters selected, average HbF value 8,6% and average leucocyte count 12.39x103/μl were prognostic indicators with different meaning to SI. The increase in the total bilirubin related to hyperhemolysis clinically explains the genesis of SI In the TCD study, only one patient had increased cerebral flow speed >196 cm/sec in CMA, which corresponded to serious vasculopathy in AngioMR. This patient never present previously neurological symptoms and had several hyperhemolysis crisis and VOC as risk factors. Low percentage of pathological TCD in this study, in relation to the high number of SI and altered tests, although without correlation among the three exams, is probably attributed to factors related to the methodology, aspects of cerebral physiopathology or perhaps a sign of good prognostic if the duration of study had not been so short. TCD should be used as a screening method in the age groups with higher risk of AVC and should never be considered separately in prophylactic therapeutics indication. Psychological tests were the most sensitive method to detect neurodevelopment impairment; in 80% of patients the neuropsychologics tests were altered, but without correlation with SI (10%). Since SI can become evident during the first two years of life and develop with time, the first psychological tests should be carried out between 3 and 5 years of age to timely be referred to special education and stimulation programs. Prognostic indicators to psychological tests were also found: alpha-thalassemia was found to be a protection factor of the IQ, just as other hematologic factors (hematocrit, MGCV and erythrocytes count). In relation to clinical parameters, although without statistical significance, patients with larger number of VOC had average lower scores versus the average in tests, except in TP. Results from different studies were conclusive as to the type of lesion found and the importance of prognostic indicators. Study 3. All the patients completed a minimum of 15 months therapeutic treatment with the final average daily dose of 19±4 mg/kg/day. The average value of the fetal hemoglobin increased significantly from 7,0±3,9% to 13,7±5,3% (p=0.028). The HbF average values increased from 6% to 15% after 15 months of therapeutic treatment. Clinically there was a reduction of 80% in the number of VOE , 69% in the number of hospitalization, 76% in the number of days of hospitalization and 67% in the number of transfusions. Once again the effectiveness of this treatment in this pediatric group, as well as the lack of any significant secondary effects, was evident. The study confirms the need for further detailed research in order to safely effect the appropriate treatment prior to the development of organic lesions, which ideally should be in the first year of life. Conclusions: These results allow us to clarify the importance of either pulmonary lesions or either nervous central system impairment among patients, children and adolescents, with sickle cell anemia. These lesions were demonstrated in most of the patients studied compromising their quality of life and the mortality. The treatment with HU is proved to be effective and having low toxicity.

Multi-objective Parallel Particle Swarm Optimization for Day-ahead Vehicle-To-Grid Scheduling

This paper presents a methodology for multi-objective day-ahead energy resource scheduling for smart grids considering intensive use of distributed generation and Vehicle- To-Grid (V2G). The main focus is the application of weighted Pareto to a multi-objective parallel particle swarm approach aiming to solve the dual-objective V2G scheduling: minimizing total operation costs and maximizing V2G income. A realistic mathematical formulation, considering the network constraints and V2G charging and discharging efficiencies is presented and parallel computing is applied to the Pareto weights. AC power flow calculation is included in the metaheuristics approach to allow taking into account the network constraints. A case study with a 33-bus distribution network and 1800 V2G resources is used to illustrate the performance of the proposed method.

Modified Discrete PSO to Increase the Delivered Energy Probability in Distribution energy Systems

This paper proposes a PSO based approach to increase the probability of delivering power to any load point by identifying new investments in distribution energy systems. The statistical failure and repair data of distribution components is the main basis of the proposed methodology that uses a fuzzyprobabilistic modeling for the components outage parameters. The fuzzy membership functions of the outage parameters of each component are based on statistical records. A Modified Discrete PSO optimization model is developed in order to identify the adequate investments in distribution energy system components which allow increasing the probability of delivering power to any customer in the distribution system at the minimum possible cost for the system operator. To illustrate the application of the proposed methodology, the paper includes a case study that considers a 180 bus distribution network.

Cost Allocation Model for Distribution Networks Considering High Penetration of Distributed Energy Resources

The high penetration of distributed energy resources (DER) in distribution networks and the competitiveenvironment of electricity markets impose the use of new approaches in several domains. The networkcost allocation, traditionally used in transmission networks, should be adapted and used in the distribu-tion networks considering the specifications of the connected resources. The main goal is to develop afairer methodology trying to distribute the distribution network use costs to all players which are usingthe network in each period. In this paper, a model considering different type of costs (fixed, losses, andcongestion costs) is proposed comprising the use of a large set of DER, namely distributed generation(DG), demand response (DR) of direct load control type, energy storage systems (ESS), and electric vehi-cles with capability of discharging energy to the network, which is known as vehicle-to-grid (V2G). Theproposed model includes three distinct phases of operation. The first phase of the model consists in aneconomic dispatch based on an AC optimal power flow (AC-OPF); in the second phase Kirschen’s andBialek’s tracing algorithms are used and compared to evaluate the impact of each resource in the net-work. Finally, the MW-mile method is used in the third phase of the proposed model. A distributionnetwork of 33 buses with large penetration of DER is used to illustrate the application of the proposedmodel.

Definition of Distribution Network Tariffs Considering Distribution Generation and Demand Response

The use of distribution networks in the current scenario of high penetration of Distributed Generation (DG) is a problem of great importance. In the competitive environment of electricity markets and smart grids, Demand Response (DR) is also gaining notable impact with several benefits for the whole system. The work presented in this paper comprises a methodology able to define the cost allocation in distribution networks considering large integration of DG and DR resources. The proposed methodology is divided into three phases and it is based on an AC Optimal Power Flow (OPF) including the determination of topological distribution factors, and consequent application of the MW-mile method. The application of the proposed tariffs definition methodology is illustrated in a distribution network with 33 buses, 66 DG units, and 32 consumers with DR capacity.

Paracoccidioidomycosis in children in the state of Rio de Janeiro (Brazil): Geographic distribution and the study of a "reservarea"

Thirty six cases of acute disseminated paracoccidioidomycosis in 3 to 12 year-old children, natives of the state of Rio de Janeiro, were seen in the period 1981-1996. All patients were residents in the rural region of 15 counties, scattered on the Southwestern part of this state. The rural region of two neighboring counties, where 16 cases (44.4%) occurred, was visited. It exhibited the environmental conditions that are considered favorable to the survival of P. brasiliensis. The most important of these conditions, abundant watercourses and autochthonous forest, are distributed on well defined and limited areas, in which the dwellings are also localized. Probably, a careful epidemiological study of forthcoming cases of the disease in children may facilitate the search for the micro-niche of the fungus.