Baseline MELD score predicts hepatic decompensation during antiviral therapy in patients with chronic hepatitis C and advanced cirrhosis

Background and Aims: In patients with advanced liver cirrhosis due to chronic hepatitis C virus (HCV) infection antiviral therapy with peginterferon and ribavirin is feasible in selected cases only due to potentially life-threatening side effects. However, predictive factors associated with hepatic decompensation during antiviral therapy are poorly defined. Methods: In a retrospective cohort study, 68 patients with HCV-associated liver cirrhosis (mean MELD score 9.18±2.72) were treated with peginterferon and ribavirin. Clinical events indicating hepatic decompensation (onset of ascites, hepatic encephalopathy, upper gastrointestinal bleeding, hospitalization) as well as laboratory data were recorded at baseline and during a follow up period of 72 weeks after initiation of antiviral therapy. To monitor long term sequelae of end stage liver disease an extended follow up for HCC development, transplantation and death was applied (240weeks, ±SD 136weeks). Results: Eighteen patients (26.5%) achieved a sustained virologic response. During the observational period a hepatic decompensation was observed in 36.8%. Patients with hepatic decompensation had higher MELD scores (10.84 vs. 8.23, p14, respectively. Baseline MELD score was significantly associated with the risk for transplantation/death (p<0.001). Conclusions: Our data suggest that the baseline MELD score predicts the risk of hepatic decompensation during antiviral therapy and thus contributes to decision making when antiviral therapy is discussed in HCV patients with advanced liver cirrhosis

Polymers for spacecraft hardware - Materials characterization, part I Interim report, Mar. - Dec. 1966

Environmental testing of polymeric materials for spacecraft hardwar

Human operator identification model and related computer programs

Four computer programs which provide computational assistance in the analysis of man/machine systems are reported. The programs are: (1) Modified Transfer Function Program (TF); (2) Time Varying Response Program (TVSR); (3) Optimal Simulation Program (TVOPT); and (4) Linear Identification Program (SCIDNT). The TV program converts the time domain state variable system representative to frequency domain transfer function system representation. The TVSR program computes time histories of the input/output responses of the human operator model. The TVOPT program is an optimal simulation program and is similar to TVSR in that it produces time histories of system states associated with an operator in the loop system. The differences between the two programs are presented. The SCIDNT program is an open loop identification code which operates on the simulated data from TVOPT (or TVSR) or real operator data from motion simulators

Outgassing Data for Selecting Spacecraft Materials

This tenth compilation of outgassing data of materials intended for spacecraft use supersedes Reference Publication 1124, Revision 2, November 1990. The data were obtained at the Goddard Space Flight Center (GSFC), utilizing equipment developed at Stanford Research Institute (SRI) under contract to the Jet Propulsion Laboratory (JPL). SRI personnel developed an apparatus for determining the mass loss in vacuum and for collecting the outgassed products. The outgassing data have been presented in three different ways in order to facilitate material selection. In Section A, the materials are divided by category into the 18 probable uses, such as adhesives, greases, paints, potting compounds, and so forth. In Section B, all the materials contained in Section A are listed in alphabetical order by the manufacturer's identification. In Section C, the only materials listed are those having 'Total Mass Loss' (TML) and Collected Volatile Condensable Materials (CVCM) equal to or lower than a maximum 1.0 percent TML and a maximum 0.10 percent CVCM. These are grouped by use, as in Section A

Analysis of flexible aircraft longitudinal dynamics and handling qualities. Volume 2: Data

Two analysis methods are applied to a family of flexible aircraft in order to investigate how and when structural (especially dynamic aeroelastic) effects affect the dynamic characteristics of aircraft. The first type of analysis is an open loop modal analysis technique. This method considers the effect of modal residue magnitudes on determining vehicle handling qualities. The second method is a pilot in the loop analysis procedure that considers several closed loop system characteristics. Both analyses indicated that dynamic aeroelastic effects caused a degradation in vehicle tracking performance, based on the evaluation of some simulation results. Volume 2 consists of the presentation of the state variable models of the flexible aircraft configurations used in the analysis applications mode shape plots for the structural modes, numerical results from the modal analysis frequency response plots from the pilot in the loop analysis and a listing of the modal analysis computer program

Compatibilization of highly sustainable polylactide/almond shell flour composites by reactive extrusion with maleinized linseed oil

Highly sustainable composites were produced by melt compounding polylactide (PLA) with almond shell flour (ASF), a processed by-product of the food industry, at a constant weight content of 30 wt.-%. However, due to the lack of miscibility between PLA and ASF, both being raw materials obtained from crops, resultant green composite presented poor ductility and low thermal stability. To overcome this limitation, maleinized linseed oil (MLO), a multi-functionalized plant-derived additive, was originally incorporated as a reactive compatibilizer during the extrusion process. Both chemical and physical characterizations showed that 1–5 parts per hundred resin (phr) of MLO successfully serve to obtain PLA/ASF composites with improved mechanical, thermal, and thermomechanical properties. The enhancement achieved was particularly related to a dual compatibilizing effect of plasticization in combination with melt grafting. The latter process was specifically ascribed to the formation of new carboxylic ester bonds through the reaction of the multiple maleic anhydride functionalities present in MLO with the hydroxyl groups of both the PLA terminal chains and cellulose on the ASF surface. The fully bio-based and biodegradable composites described herein give an efficient sustainable solution to upgrade agro-food wastes as well as contributing to reducing the cost of PLA-based materials

A Hydrogeologic Evaluation of the Waterloo Area in the Upper Jefferson River Valley, Montana

The Upper Jefferson River is one of the most dewatered rivers in Montana. The river exists in an intermontane basin filled with sediment transported from the Highland Mountains to the west, the Tobacco Root Mountains to the east, and the Jefferson River from the south. The Upper Jefferson River Valley is highly dependent on the Jefferson River as the main industry in the valley is agriculture. A majority of the valley is irrigated and used to grow crops, and a good portion is also used for cattle grazing. The residents of the Upper Jefferson River Valley use the aquifer as the main source of potable water. The Jefferson River is also widely used for recreation. This study took place in the Waterloo area of the Upper Jefferson River Valley, approximately 20 miles south of Whitehall, Montana. The Waterloo area provides significant groundwater base flow to the Jefferson River, which is particularly important during the late irrigation season when the river is severely dewatered, and elevated surface-water temperatures occur, creating irrigation water shortages and poor trout habitat. This area contains two springfed streams, Willow Springs and Parson’s Slough, which discharge to the Jefferson River providing cool water in the late season as well as providing the most important trout spawning habitat in the valley. The area is bordered on both the east and west by irrigation ditches, and about 60% of the study area is irrigated. Tile drains were installed in the study area in close proximity to Parsons Slough causing some concern by neighboring residents. This study evaluated relationships between surface water, groundwater, and irrigation practices so that water managers and others can make informed management decisions about the Upper Jefferson River. Data was collected via a network of groundwater wells and surface-water sites. Additionally, water-quality samples were taken and an aquifer test was conducted to determine aquifer properties. The field data were analyzed and a groundwater budget was created in order to evaluate the aquifer. Results of the groundwater budget show that seepage from the irrigation canals and irrigation recharge have the biggest influence on recharge of the aquifer. There is significant groundwater outflow from the aquifer in the spring-fed streams as well as discharge to the Jefferson River. In comparing previous study results to this study’s results, there is no evidence of the water table decreasing due to irrigation practice changes or tile drain installation. However, given the amount of recharge irrigation practices contribute to the aquifer, if significant changes were made, they may affect groundwater elevations. Also lining the irrigation ditches would have a significant impact on the aquifer, as the amount of seepage would be greatly reduced

Assessment of Time Allocated to Pedestrian Crossing: A Contribution for a More Inclusive Lisbon

Introdução: Com o envelhecimento progressivo da população portuguesa, é fundamental que as condições de acessibilidade e segurança na via pública estejam adaptadas a este grupo etário. O objectivo deste estudo foi avaliar se o tempo atribuído à travessia de peões nas passadeiras semaforizadas entre o Hospital de Curry Cabral e os transportes públicos locais é suficiente para permitir a travessia dos idosos em segurança. Material e Métodos: Foram avaliados 100 doentes seguidos em consulta externa no Serviço de Medicina Física e de Reabilitação. Todos responderam a um questionário, à escala de confiança no equilíbrio específica da atividade e executaram o teste de marcha de 10 metros. Foram analisadas todas as passadeiras semaforizadas dos percursos de marcha entre o hospital e os transportes públicos locais, num total de 26 e calculada a velocidade de marcha necessária para realizar a travessia das passadeiras em segurança. Resultados: A média de idade dos doentes foi de 75 anos, sendo a maioria do género feminino (73%). Concluímos que todos os doentes conseguem atravessar em segurança 17 (65%) passadeiras, representando as restantes nove (35%) um obstáculo para a nossa amostra. Discussão: Se o valor de velocidade de marcha nas passadeiras estipulado na legislação para os cidadãos com mobilidade condicionada fosse devidamente aplicado, 99% da amostra teria conseguido atravessar as passadeiras em segurança. Conclusão: É fundamental que o valor de velocidade de marcha nas passadeiras estipulado na legislação seja aplicado, pois o seu incumprimento coloca em risco os utentes idosos do Hospital de Curry Cabral, aumentando a probabilidade de acidentes e o sentimento de insegurança na via pública.info:eu-repo/semantics/publishedVersio

Recuperação das propriedades de termoplástico reprocessado para fabrico por filamento fundido em ciclo fechado

Additive manufacturing technologies based on Material Extrusion (ME) have been growing, gaining popularity and maturity in the plastic processing sector. In this context, it is a major concern to establish a closed-loop plastic production system which allows to maximize the value and shell-life of the feedstocks used in these kind of manufacturing technologies, contributing to decrease their ecological footprint. Regarding ME or Fused Filament Fabrication (FFF), a possible closed-loop recycling scheme would consist of processes for material collection, preparation, and filament extrusion in order to produce 3D printing feedstocks that fits with the FFF requirements and allows to achieve new value-added parts. However, there are challenges to overcome related to the quality and performance of the recycled materials, since, after mechanical recycling, the molecular degradation of thermoplastics causes a shift on their properties, and, therefore, on their processability. In this work, it was hypothesized that the incorporation of chain extenders (CE) during the reprocessing cycle would allow to overcome these drawbacks. To attest this conjecture, the inuence of 1,3-Bis(4,5-dihydro-2-oxazolyl)benzene (PBO), a functional additive used as a CE for polylactic acid (PLA) and PLAbased blends, at a fixed concentration (1%, w/w) on mechanical, thermal, and rheological properties of recycled PLA-based filaments was studied, using virgin PLA-based material as control. PBO was able to partially recover the mechanical performance of recycled PLA-based systems, as reected by an increase in both tensile modulus and tensile strength of the filament specimens. However, these results did not corroborate with the evolution of the material's melt strength, monitored by the melt ow rate (MFR), since PBO increased the MFR of recycled PLA-based formulation. This behavior may be related to the low interaction established between PBO and PLA, as observed by Fourier transform infrared spectroscopy (FTIR). From the printability point of view, it was observed that the brittleness of each studied formulation remained as the major constraint for successfully establish a closed-loop recycling scheme for FFF.As tecnologias de manufatura aditiva baseadas em extrusão de materiais termoplásticos como o Fabrico por Filamento Fundido (FFF) têm-se destacado, ganhando popularidade e maturidade no contexto da indústria de processamento de plásticos. Desta forma, o esbelecimento de modelos de produção de plásticos em ciclo fechado é uma área de extremo interesse, pois possibilita maximizar o valor dos materiais utilizados neste tipo de tecnologias de fabrico, contribuindo igualmente para a redução do seu impacto ambiental. No contexto do FFF, um possível sistema de reciclagem em ciclo fechado consiste nos processos de recolha, preparação dos materiais e extrusão de filamento com o objetivo de conformar o material de forma a que este possa cumprir os requisitos da tecnologia, possibilitando a produção de componentes de valor acrescentado. Contudo, existem um conjunto de desafios associados à qualidade e performance dos materiais reciclados, dado que, após a aplicação dos processos de reciclagem mecânica, a degradação ao nível molecular a que os materiais termoplásticos são sujeitos irá provocar uma alteração nas suas propriedades e, consequentemente, nas suas condições de processamento. Neste estudo, é colocada a hipótese de, através da utilização de extensores da cadeia (EC) polimérica durante o ciclo de reprocessamento, ultrapassar as limitações relacionadas com a excessiva degradação do material. Neste sentido, a influência do 1,3-Bis(4,5-dihydro-2-oxazolyl) benzene (PBO), um aditivo funcional utilizado como extensor da cadeia para o ácido poliláctico (PLA) e formulações baseadas em PLA, a uma dada concentração (1%, m/m), nas propriedades mecânicas, térmicas e reológicas do material foi estudada, utilizando PLA virgem como material de controlo. A incorporação do PBO permitiu a recuperação parcial das propriedades mecânicas dos sistemas baseados em PLA reciclado, refletido pelo aumento do modulo de elasticidade e da tensão de rotura nas amostras de filamento. No entanto, estes resultados não são comprovados pela evolução da fluidez do material, monotorizada através do índice de fluidez (MFR), dado que o PBO contribuiu para o aumento do MFR das formulações baseadas em PLA reciclado. Este comportamento pode estar relacionado com a interação limitada entre o PBO e o PLA, observada através da espetroscopia de infravermelho por transformada de Fourier (FTIR). Na perspetiva da capacidade de impressão, o comportamento frágil do material foi identificado como a maior limitação ao estabelecimento de um sistema de reciclagem em ciclo fechado para aplicações na tecnologia de FFF.Mestrado em Engenharia Mecânic