34 research outputs found

    An Optimal Control Framework to Address the Relationship between Water Resource Management and Water-Borne Health Impacts: Focus on the Texas Lower Rio Grande Valley

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    The objective of this study is develop a theoretical model that can evaluate two types of public health expenditures on water-borne health risks: water-related municipal services, an ex ante preventative measure against water-borne contamination, and medical treatment, an ex post treatment of the water-borne pollutant’s harmful effects on human health. The modeled community can allocate resources in either centralized-municipal water-services, point-of-use water-services, or medical intervention, with expenditures subject to a budget constraint. The movement of a water-borne illness through the community is modeled with a susceptible-infected-susceptible (SIS) disease framework. An optimization framework is developed, including a statement of the problem’s Hamiltonian and first-order-conditions. The first-order-conditions are discussed. Future work includes obtaining a numerical solution to the optimization problem.water, public health, rural development, dynamic optimization, Community/Rural/Urban Development, Resource /Energy Economics and Policy,

    Seawater Desalination for Municipal Water Production

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    This paper examines the optimal allocation of several inputs in the context of seawater desalination by reverse osmosis (RO) as a source of municipal (or commercial or industrial) water. A cost-minimization model is developed, a production function is estimated, and sensitivity analyses are conducted using the optimization model to investigate the effect of environmental conditions and economic factors on the optimal input portfolio and the cost of operating a modeled seawater desalination facility. The objectives of this paper are to better understand the effect on the seawater desalination facility’s costs and input portfolio from changes in water quality, membrane lifespan, daily operations schedule, and energy prices. Findings include that lower total facility costs are associated with warm-weather water quality parameters, longer membrane life, and mid-range daily operations schedule (14.265 hours/day). Under most conditions, an interruptible power supply regime reduces facility costs. Exceptions include when the interruptible power supply regime implies significant reductions in operating hours and the associated reduction in energy price is very small.water, production, seawater desalination, Resource /Energy Economics and Policy,

    A História da Alimentação: balizas historiográficas

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    Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domínio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crítico da historiografia brasileira sobre o tema

    31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

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    Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

    An Optimal Control Framework to Address the Relationship between Water Resource Management and Water-Borne Health Impacts: Focus on the Texas Lower Rio Grande Valley

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    The objective of this study is develop a theoretical model that can evaluate two types of public health expenditures on water-borne health risks: water-related municipal services, an ex ante preventative measure against water-borne contamination, and medical treatment, an ex post treatment of the water-borne pollutant’s harmful effects on human health. The modeled community can allocate resources in either centralized-municipal water-services, point-of-use water-services, or medical intervention, with expenditures subject to a budget constraint. The movement of a water-borne illness through the community is modeled with a susceptible-infected-susceptible (SIS) disease framework. An optimization framework is developed, including a statement of the problem’s Hamiltonian and first-order-conditions. The first-order-conditions are discussed. Future work includes obtaining a numerical solution to the optimization problem

    The Effect of Distance and Cost on Fruit and Vegetable Consumption in Rural Texas

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    Fruit and vegetable consumption is associated with improved health outcomes, yet there is limited understanding of the impact of cost and accessibility on fruit and vegetable intake in rural settings. This study examines the relationship between the consumption of fruits and vegetables and their cost and accessibility among blacks and non-Hispanic whites in a rural area. Individual characteristics from a 2006 mail survey (n 5 1,510) were combined with store locations and price information from a 2006 ground-truthed census of retail outlets. The mail survey covered seven counties in central Texas with 38 supermarkets/grocery stores. Blacks tended to live closer to a supermarket or grocery store, but they were only slightly more likely than whites to consume two or more servings of fruit daily and much less likely to consume three or more servings of vegetables. Multivariate probit regression analysis revealed that neither access nor cost was related to fruit or vegetable consumption among white respondents. Among blacks, cost was also not associated with consumption. In contrast to whites, however, each additional mile was associated with a three percentage point decline in the probability of consuming two or more servings of fruit daily and a 1.8 percentage point decline in the probability of consuming three or more vegetable servings
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