Proportional service differentiation with MPLS

This paper describes two traffic engineering techniques for implementing proportional differentiated services based on Multiprotocol Label Switching constraint based routing. Both use a dynamic bandwidth allocation scheme to modify the bandwidth reserved by each traffic class according to the current network load. The first scheme uses an adaptive algorithm that qualitatively determines the required average throughput per source for each class and moves bandwidth between classes for each path as necessary. The second scheme mathematically divides the existing bandwidth through the traffic classes for each path. The quality of service that users get with both techniques is assessed by simulation and compared with a fixed bandwidth allocation scheme.5th IFIP International Conference on Network Control & Engineering for QoS, Security and MobilityRed de Universidades con Carreras en Informática (RedUNCI

Modelação hidrodinâmica de escoamentos costeiros

As zonas costeiras, os estuários e os sistemas lagunares são regiões de elevada importância do ponto de vista económico devido à intensa actividade nelas desenvolvida. Encontram-se por esse motivo sujeitas a fortes pressões do tipo ambiental. A correcta gestão dos seus recursos deve ser apoiada em ferramentas que possibilitem uma análise precisa dos fenómenos que nelas ocorrem e permitam a previsão da evolução desses sistemas. A recente evolução na capacidade de cálculo dos computadores de pequeno porte tornou viável a utilização de modelos hidrodinâmicos como ferramentas de apoio à decisão

A three-dimensional hydrodynamic model with generic vertical coordinate

A three-dimensional primitive equation model and its application to a tidal estuary is described. The model solves the primitive equations for incompressible fluids with Boussinesq and hydrostatic approximations. The discretization is based on the finite volume method and allows a general vertical coordinate. The computational code is implemented in such a way that different vertical coordinates can be used in different parts of the domain. The model was designed to be able to simulate the flow both in the open ocean and in coastal and estuarine zones and can be coupled in a simple way to ecological models. The model was implemented successfully in several estuarine and coastal areas. Results are show for the Sado estuary in Portugal to illustrate model accuracy and potential. Quantitative validation is based on field data (water levels and velocities) while qualitative verification is based on the analysis of secondary flows

Simulating water mixing in a barotropic estuary: the effect of vertical discretization

Mixing between estuarine and coastal waters is strongly dependent on the processes that occur in the vertical direction. This applies both for stratified and homogeneous estuaries. In homogeneous estuaries important recirculation flows in the vertical plane can arise, in regions with strong batimetry gradients, produced by the combined action of inertia and friction. On the Platform close to the inlet this structures can trap estuarine water during the ebb period, releasing it to the interior again during the flood

A methodology to estimate the residence time of estuaries

The residence time has long been used as a classification parameter for estuaries and other semi- enclosed water bodies. It aims to quantify the time water remains inside the estuary, being used as an indicator both for pollution assessment and for ecological processes. Estuaries with a short residence time will export nutrients from upstream sources more rapidly then estuaries with longer residence time. On the other hand the residence time determines if micro-algae can stay long enough to generate a bloom. As a consequence, estuaries with very short residence time are expected to have much lower algae blooms, then estuaries with longer residence time. In addition, estuaries with residence times shorter than the doubling time of algae cells will inhibit formation of algae blooms (EPA, 2001). The residence time is also an important issue for processes taking place in the sediment. The fluxes of particulate matter and associated adsorbed species from the water column to the sediment depends of the particle’s vertical velocity, water depth and residence time. This is particularly important for the fine fractions with lower sinking velocities. The question is how to compute the residence time and how does it depend on the computation method adopted

Proportional service differentiation with MPLS

This paper describes two traffic engineering techniques for implementing proportional differentiated services based on Multiprotocol Label Switching constraint based routing. Both use a dynamic bandwidth allocation scheme to modify the bandwidth reserved by each traffic class according to the current network load. The first scheme uses an adaptive algorithm that qualitatively determines the required average throughput per source for each class and moves bandwidth between classes for each path as necessary. The second scheme mathematically divides the existing bandwidth through the traffic classes for each path. The quality of service that users get with both techniques is assessed by simulation and compared with a fixed bandwidth allocation scheme.5th IFIP International Conference on Network Control & Engineering for QoS, Security and MobilityRed de Universidades con Carreras en Informática (RedUNCI

From regional to local scale modelling on the south-eastern Brazilian shelf: case study of Paranaguá estuarine system

A aplicabilidade de um modelo numérico seguindo uma metodologia de downscaling foi avaliada para a plataforma sudeste brasileira (modelo regional) e o sistema estuarino de Paranaguá (modelo local). Esta abordagem permite simular fenômenos de escalas diferentes, como maré meteorológica e ressurgência costeira, e é apropriada para fins de previsão operacional. Quando grandes áreas são cobertas por modelos regionais, a propagação da maré no interior do domínio pode ser afetada significativamente pelo potencial local da maré, principalmente onde o fenômeno de ressonância é observado. A plataforma sudeste brasileira é conhecida pela ressonância da constituinte da maré lunar principal terci-diurna (M3), com as maiores amplitudes encontradas no sistema estuarino de Paranaguá. Por este motivo, a significância do potencial local da maré foi verificada neste estudo para as constituintes da maré mais importantes dentro do sistema estuarino (incluindo a M3). A validação do modelo foi realizada com dados de marégrafos, perfis de boias Argo e medições de satélite da temperatura da superfície do mar. A metodologia descrita neste estudo pode ser replicada para outros sistemas estuarinos importantes localizados na plataforma sudeste brasileira. Além disso, o modelo numérico foi desenvolvido na perspectiva de simulações operacionais em nowcast/forecast, úteis para diversas atividades, como navegação e resposta a emergências (e.g., derrames de petróleo).The applicability of a numerical model following a downscaling methodology was evaluated for the south-eastern Brazilian shelf (regional model) and Paranaguá estuarine system (local model). This approach permits the simulation of different scale processes, such as storm surges and coastal upwelling, and is suitable for operational forecasting purposes. When large areas are covered by regional models, the tidal propagation inside the domain can be significantly affected by the local tidal potential, mainly where the resonance phenomenon is observed. The south-eastern Brazilian shelf is known for the resonance of the third-diurnal principal lunar tidal constituent (M3), the largest amplitudes being found in the Paranaguá estuarine system. Therefore, the significance of the local tidal potential was assessed in this study for the most important tidal constituents inside the estuarine system (including M3). The model validation was performed with tidal gauge data, Argo float profiles and satellite measurements of Sea Surface Temperature. The methodology described in this study can be replicated for other important estuarine systems located on the south-eastern Brazilian shelf. Furthermore, the numerical model was developed within a perspective of operational nowcast/forecast simulations, useful for several activities such as navigation and response to emergencies (e.g., oil spills)

Infertilidade masculina associada ao uso de finasterida

Finasteride is a potent and specific inhibitor of the 5alpha-reductase enzyme in men. Clinical studies have shown that finasteride 1mg/day is effective for promoting hair growth in men with male pattern hair loss. However, there is a concern about the use of finasteride, especially in young fertile patients, because of its action on testosterone metabolism. This paper describes 3 cases of young patients who had very poor seminal quality during finasteride treatment (1 mg/day), and their seminal quality greatly improved after cessation of finasteride treatment. Two of them presented with a left varicocele and the other was obese. We hypothesize that finasteride may not dramatically change the spermatogenesis process in healthy men, but in patients with conditions related to infertility, an amplification of the negative influence of finasteride could occur. Future studies should be done to clarify the extent of the effect of finasteride in patients fertility problems.A finasterida é um potente e específico inibidor da enzima 5alfa-redutase em homens. Estudos clínicos demonstraram que finasterida 1mg/dia diminui a progressão da queda e aumenta o crescimento do cabelo em homens que sofrem de queda de cabelo hereditária. Por sua influência no metabolismo dos andrógenos existe uma preocupação a respeito do seu uso, principalmente em pacientes em idade fértil. Neste trabalho são descritos 3 casos de pacientes jovens, que apresentaram piora do espermograma durante o uso continuado de finasterida 1mg revertida após a suspensão do mesmo. Dois deles tinham varicocele unilateral e o terceiro era obeso. Aparentemente o tratamento com finasterida promoveu alteração significativa na qualidade seminal. Pode-se especular que talvez a finasterida por si só não traga alteração para a espermatogênese como reportado por Overstreet et al. (1999), mas que em pacientes de risco com possíveis causas de infertilidade associadas, possa ocorrer a amplificação da influência deletéria da finasterida. Estudos futuros devem ser realizados para esclarecer a influência da finasterida nestes pacientes

Development of an integrated system for coastal waters

This paper describes some of the needs and problems associated to assessment of coastal and estuarine problems (sediment transport and eutrophication). The development of an integrated system including EO data, local measurements with special emphasis on modeling tools, is presented as a solution for studying and helping decision making on the subject. Two pilot sites for the implementation and the present development status of the integrated system are depicted. This framework was already presented in a recent AO specific for Portugal, which is still under evaluation

Gestational weight gain, nutritional status and blood pressure in pregnant women

OBJECTIVE: To evaluate whether weekly gestational weight gain is associated with anemia, vitamin A insufficiency, and blood pressure levels in the third trimester of pregnancy. METHODS: A prospective study with 457 pregnant women attending primary care in Cruzeiro do Sul, Acre. The weekly gestational weight gain rate measured between the second and third trimesters was classified as insufficient, adequate, and excessive according to the recommendations of the Institute of Medicine 2009. The outcomes at the beginning of the third gestational trimester were: anemia (Hb < 110 g/L), vitamin A insufficiency (serum retinol<1.05 μmol/L) and blood pressure levels (continuous values, in mmHg). Age-adjusted prevalence ratios, schooling, and use of vitamin and mineral supplements were calculated in Poisson regression models with robust variance. RESULTS: A total of 18.6% of pregnant women had insufficient weekly weight gain, and 59.1% had excessive weight gain. The frequencies of anemia, vitamin A insufficiency and hypertension (systolic blood pressure ≥ 140 mmHg or diastolic ≥ 90 mmHg) were 17.5%, 13.4%, and 0.6%, respectively. The prevalence ratios for anemia among pregnant women with insufficient and excessive weight gain were 0.41 (95%CI 0.18–0.93) and 1.00 (95%CI 0.63–1.59), respectively, when compared to pregnant women with adequate weight gain. For vitamin A insufficiency, the adjusted prevalence ratio was significantly higher among pregnant women with insufficient weight gain (2.85, 95%CI 1.55–5.24) and no difference for excessive weight gain (1.53, 95%CI 0.84–2.74) when compared to pregnant women with adequate weight gain. Pregnant women with excessive weight gain had higher mean systolic blood pressure (111.10; 95%CI 109.9–112.2) when compared to pregnant women with insufficient weight gain (107.50; 95%CI 105.4–109.6) and adequate (106.20; 95%CI 104.3–108.20). CONCLUSIONS: Insufficient weekly gestational weight gain was associated with the risk of vitamin A insufficiency. Excessive weight gain, in turn, was associated with higher blood pressure values at the beginning of the third gestational trimester