1,341 research outputs found
Impacts of the Proposals For Tariff Reductions in Non-Agricultural Market Access (Nama)
O Estudo Visa Avaliar os Impactos de Propostas Alternativas de Redução da Proteção Tarifária de Bens NĂŁo-AgrĂcolas Sobre a Economia Brasileira Usando um Modelo de EquilĂbrio Geral Computável. Foram Simulados os Impactos da Implementação de Cortes Tarifários de Acordo com Diferentes Coeficientes para a FĂłrmula SuĂça. as Simulações Foram Realizadas com o Modelo Gtap e Todos os Choques Tarifários Foram Calculados a Partir de Informações da Base de Dados Macmap. AlĂ©m de Analisar Resultados MacroeconĂ´micos e Setoriais, TambĂ©m foi Testada a Sensibilidade dos Resultados em Relação ao Aumento das Elasticidades de Armington e Ă€ OcorrĂŞncia de uma Simultânea Liberalização de Tarifas Sobre Bens AgrĂcolas.
Evidence-based recommendation on toothpaste use
Toothpaste can be used as a vehicle for substances to improve the oral health of individuals and populations. Therefore, it should be recommended based on the best scientific evidence available, and not on the opinion of authorities or specialists. Fluoride is the most important therapeutic substance used in toothpastes, adding to the effect of mechanical toothbrushing on dental caries control. The use of fluoride toothpaste to reduce caries in children and adults is strongly based on evidence, and is dependent on the concentration (minimum of 1000 ppm F) and frequency of fluoride toothpaste use (2Ă—/day or higher). The risk of dental fluorosis due to toothpaste ingestion by children has been overestimated, since there is no evidence that: 1) fluoride toothpaste use should be postponed until the age of 3-4 or older, 2) low-fluoride toothpaste avoids fluorosis and 3) fluorosis has a detrimental effect on the quality of life of individuals exposed to fluoridated water and toothpaste. Among other therapeutic substances used in toothpastes, there is evidence that triclosan/copolymer reduce dental biofilm, gingivitis, periodontitis, calculus and halitosis, and that toothpastes containing stannous fluoride reduce biofilm and gingivitis.Toothpaste can be used as a vehicle for substances to improve the oral health of individuals and populations. Therefore, it should be recommended based on the best scientific evidence available, and not on the opinion of authorities or specialists. Fluoride is the most important therapeutic substance used in toothpastes, adding to the effect of mechanical toothbrushing on dental caries control. The use of fluoride toothpaste to reduce caries in children and adults is strongly based on evidence, and is dependent on the concentration (minimum of 1000 ppm F) and frequency of fluoride toothpaste use (2Ă—/day or higher). The risk of dental fluorosis due to toothpaste ingestion by children has been overestimated, since there is no evidence that: 1) fluoride toothpaste use should be postponed until the age of 3-4 or older, 2) low-fluoride toothpaste avoids fluorosis and 3) fluorosis has a detrimental effect on the quality of life of individuals exposed to fluoridated water and toothpaste. Among other therapeutic substances used in toothpastes, there is evidence that triclosan/copolymer reduce dental biofilm, gingivitis, periodontitis, calculus and halitosis, and that toothpastes containing stannous fluoride reduce biofilm and gingivitis28111
SIMULATIONS OF FISHING EFFECTS ON THE SOUTHERN BENGUELA FISH COMMUNITY USING AN INDIVIDUAL-BASED MODEL: LEARNING FROM A COMPARISON WITH ECOSIM
By applying an individual-based model (OSMOSE) to the southern Benguela ecosystem, a multispecies analysis is proposed, complementary to that provided by the application of ECOPATH/ECOSIM models. To reconstruct marine foodwebs, OSMOSE is based on the hypothesis that predation is a size-structured process. In all, 12 fish species, chosen for their importance in terms of biomass and catches, are explicitly modelled. Growth, reproduction and mortality parameters are required to model their dynamics and trophic interactions. Maps of mean spatial distribution of the species are compiled from published literature. Taking into account the spatial component is necessary because spatial co-occurrence determines potential interactions between predatory fish and prey fish of suitable size. To explore ecosystem effects of fishing, different fishing scenarios, previously examined using ECOSIM, are simulated using the OSMOSE model. They explore the effects of targeting fish species in the southern Benguela considered to be predators (Cape hake Merluccius capensis and M. paradoxus) or prey (anchovy Engraulis encrasicolus, sardine Sardinops sagax, round herring Etrumeus whiteheadi). Simulation results are compared and are generally consistent with those obtained using an ECOSIM model. This cross-validation appears to be a promising means of evaluating the robustness of model outputs, when separate validation of marine ecosystem models are still difficult to perform.Afr. J. mar. Sci. 26: 95–11
Fluoride Dentifrice Overcomes the Lower Resistance of Fluorotic Enamel to Demineralization
We evaluated if the low resistance of fluorotic enamel to demineralization could be overcome by fluoride dentifrice (FD) treatment. Paired enamel slabs of sound and fluorotic enamel (n = 20/group) from human teeth presenting Thylstrup and Fejerskov index (TF) scores from 0 to 4 were obtained. Half of the anatomic surface of the enamel slabs was isolated and used as a control (baseline) regarding enamel mineralization and fluoride concentration. The slabs were submitted to a pH-cycling model simulating a high cariogenic challenge, and 2×/day they were treated with placebo dentifrice (PD) or FD (1,100 µg F/g, as NaF). After 10 days, the slabs were cut into two halves. Enamel demineralization was evaluated by cross-sectional microhardness in one half, and the fluoride formed (FF) concentration was determined in the other half. For statistical analysis, the data on net demineralization area (ΔΔS) and FF (µg F/g) were grouped into TF0, TF1–2, and TF3–4, and analyzed by two-way ANOVA followed by Tukey’s test (α = 5%). The factors studied were TF (0, 1–2, and 3–4) and dentifrice treatment (PD or FD). The effect of the factors was statistically significant for ΔΔS and FF (p TF1–2 > TF0 (p 0.05) when FD was used. Regarding FF, the groups treated with PD did not differ (p > 0.05), but the greatest (p < 0.05) FF concentration was found in group TF3–4 treated with FD. These findings suggest that the higher susceptibility of fluorotic enamel to demineralization lesions is decreased by the use of FD
STOCHASTIC OPTIMIZATION OF MULTIPLEX CHARGES BASED ON INTERIOR BALLISTICS SIMULATIONS
Multiplex charges combine propellant grains with regressive, neutral and progressive burning behaviors in a single propellant charge to improve the interior ballistics. This work optimizes the mass and the web thickness of each type of propellant grain used in a multiplex charge. Two optimization problems are studied: the maximization of the muzzle velocity and the minimization of the maximum pressure inside the gun. Particle Swarm Optimization (PSO) and Differential Evolution (DE) were used to solve the optimization problems. The interior ballistics of a 155 mm howitzer was simulated by using a lumped parameters model. In this model, the lost energy and the resistance pressure are defined by spline functions based on reference data. The results show that optimized multiplex charges can be used to increase the weapon’s utility range and to reduce the weapon’s weight
A leucine-supplemented diet improved protein content of skeletal muscle in young tumor-bearing rats
Cancer cachexia induces host protein wastage but the mechanisms are poorly understood. Branched-chain amino acids play a regulatory role in the modulation of both protein synthesis and degradation in host tissues. Leucine, an important amino acid in skeletal muscle, is higher oxidized in tumor-bearing animals. A leucine-supplemented diet was used to analyze the effects of Walker 256 tumor growth on body composition in young weanling Wistar rats divided into two main dietary groups: normal diet (N, 18% protein) and leucine-rich diet (L, 15% protein plus 3% leucine), which were further subdivided into control (N or L) or tumor-bearing (W or LW) subgroups. After 12 days, the animals were sacrificed and their carcass analyzed. The tumor-bearing groups showed a decrease in body weight and fat content. Lean carcass mass was lower in the W and LW groups (W = 19.9 ± 0.6, LW = 23.1 ± 1.0 g vs N = 29.4 ± 1.3, L = 28.1 ± 1.9 g, P < 0.05). Tumor weight was similar in both tumor-bearing groups fed either diet. Western blot analysis showed that myosin protein content in gastrocnemius muscle was reduced in tumor-bearing animals (W = 0.234 ± 0.033 vs LW = 0.598 ± 0.036, N = 0.623 ± 0.062, L = 0.697 ± 0.065 arbitrary intensity, P < 0.05). Despite accelerated tumor growth, LW animals exhibited a smaller reduction in lean carcass mass and muscle myosin maintenance, suggesting that excess leucine in the diet could counteract, at least in part, the high host protein wasting in weanling tumor-bearing rats.1589159
Modificação do fenótipo linfocitário e aumento da sobrevida do enxerto de pele após a terapia com FTY720 + FK506
The development of new drugs to be associated with calcineurin inhibitors and promote additional immunosuppression with fewer side effects is the goal in transplantation. FTY720 is a new synthetic compound which presents immunomodulatory properties which are not fully understood. It has been reported that the main mechanism of action of FTY720 is to reduce the peripheral lymphocyte count by redirecting these cells toward secondary lymphoid organs. Skin allograft transplantation in a fully mismatched strain combination was used to investigate the potential of FTY720 alone or in combination with a calcineurin inhibitor - FK506 - in preventing rejection. The number and phenotype of immune system cells was also evaluated. FTY720 alone or in combination with FK506 provided significant skin allograft survival. FTY720+FK506 therapy was associated with decreases of total lymphocyte numbers in spleen and blood, and increases in apoptosis levels in splenocytes. In FTY720 isolated treatment, a significant decrease in the CD4 expression and significantly lower expressions of MHC II and ICAM-1 molecules were observed in spleen lymphocytes. Despite of allograft survival being the same in both FTY720 and FTY720+FK506 treated groups, the association of drugs was associated with the absence of macroscopic skin necrosis for a longer period than the other treatments (FTY720, FK506) and histology showed less cell infiltration. Our results suggest that a decrease of effector T cells due to elevated levels of apoptosis and impairment in the appearance of antigens were events associated with FTY720+FK506 administration.O objetivo na área dos transplantes Ă© o desenvolvimento de novas drogas que possam ser associadas a inibidores da calcineurina para evitar o processo de rejeição e causar menos efeitos colaterais. FTY720 Ă© um novo composto sintĂ©tico que apresenta propriedades imunomoduladoras nĂŁo completamente elucidadas. Foi relatado que o principal mecanismo de ação do FTY720 Ă© a redução do nĂşmero de linfĂłcitos perifĂ©ricos atravĂ©s do redirecionamento dessas cĂ©lulas para ĂłrgĂŁos linfĂłides secundários. O alotransplante de pele entre linhagens de camundongos completamente incompatĂveis quanto ao MHC foi usado para investigar o potencial de FTY720 isolado ou em combinação com um inibidor da calcineurina - FK506 - na prevenção da rejeição. TambĂ©m foram avaliados o nĂşmero e fenĂłtipo das cĂ©lulas do sistema imune. A administração de FTY720 como monoterapia ou FTY720+FK506 associou-se a uma diminuição do nĂşmero total de linfĂłcitos no baço e no sangue e aumento dos nĂveis de apoptose nos esplenĂłcitos. No grupo tratado somente com FTY720, foi observada uma diminuição mais importante da expressĂŁo de CD4 e expressĂŁo significativamente menor de molĂ©culas de MHC II e ICAM-1. Apesar de a sobrevida do aloenxerto ter sido igual para os grupos tratados com FTY720 ou FTY720 +FK506, a associação das drogas promoveu ausĂŞncia de necrose macroscĂłpica da pele por um perĂodo maior do que os outros tratamentos (FTY720, FK506) e os achados histolĂłgicos mostraram menor infiltrado celular. Nossos resultados sugerem que uma diminuição do nĂşmero de cĂ©lulas T efetoras devido a elevados nĂveis de apoptose e o prejuĂzo da apresentação de antĂgenos foram os eventos associados Ă administração de FTY720+FK506.Faculdade de Medicina de SĂŁo JosĂ© do Rio PretoUniversidade Federal de SĂŁo Paulo (UNIFESP)UNIFESPSciEL
- …