63 research outputs found
Experimental validation of MED forward feed steady-state model
In this work the validation of a physical model to simulate the performance of an MED forward feed system is done by comparing results of the model with real data obtained. The data was obtained using the experimental MED plant at Plataforma Solar de Almeria (PSA) under steady-state operation near design conditions. The results indicate that the model can be used to make a first analysis on these type of systems.
Exergy cost assessment of solar trigeneration plant based on a concentrated solar power plant as the prime mover
An exergy cost assessment of solar trigeneration plant to generate electricity, fresh-water, and heat is carried out in order to study the process of exergy cost formation, to determine the key components that contribute to the cost of each product, and to establish the best configuration in term of unit exergy cost. The solar trigeneration plants evaluated consist of a concentrated solar power (CSP), a multi-effect distillation plant, and a process heat module, in which the CSP plant is the prime mover. The methodology includes modeling and evaluating the performance of standalone and trigeneration plants using the symbolic exergoeconomic methodology. Results show that the best configuration, in terms of exergy cost, is when the multi-effect distillation plant replaces the power cycle condenser. Regarding the costs formation, the key components which could be improved in their design are: solar collectors, evaporator, re-heater, dissipative systems, and productive subsystems
Modeling multi effect distillation powered by CSP in TRNSYS
This work presents the results of using a new tool to simulate the cogeneration of water and electricity with Concentrating Solar Power (CSP) and Forward Feed Multi-Effect-Desalination (FF-MED) plants, by adding a new functionality to the System Advisor Model (SAM) developed by the US National Renewable Energy Laboratory (NREL). The controlling strategy of the MED model is presented in detail, and a case study application is shown. This study compares the results obtained with a CSP plant operating in San Diego, CA, with four different cooling systems: an MED/Seawater Cooling Circuit (SWCC), dry cooling, wet cooling, and a SWCC standalone. The results show that the usage of an MED/SWCC system in cogeneration with a CSP plant can be feasible and has the potential to be economically interesting
Optimización del desarrollo de la energia termosolar en españa en el contexto de la transición energética
CIES2020 - XVII Congresso Ibérico e XIII Congresso Ibero-americano de Energia SolarRESUMEN: Este artículo presenta un resumen de los resultados obtenidos al estudiar cuál debe ser la evolución del mix eléctrico en España durante los próximos 30 años si se desea cumplir con determinados escenarios de reducción de las emisiones de CO2 del sector eléctrico en relación a las del año 1990. El estudio se ha realizado usando un algoritmo genético con optimización multiobjetivo. Se han considerado dos escenarios de reducción de emisiones de CO2: 1) escenario moderado del 40% (2030), 60% (2040) y 80% (2050); 2) escenario agresivo del 50% (2030), 75% (2040) y 100% (2050). Los resultados mostrados en este artículo indican que el escenario moderado es factible, sin que ello conlleve altos costes de la electricidad o excesivos vertidos. Una reducción del 80% en las emisiones de CO2 en el año 2050 requerirá un mix eléctrico renovable en un 86.34% y conllevaría un coste aproximado de la electricidad de 47,4 €/MWh. Pero si se desea cumplir el escenario agresivo (mercado eléctrico sin emisiones de CO2 en 2050) el mix eléctrico necesario supondría un coste de 62,9 €/MWh para la electricidad suministrada a la red y unos vertidos de 222,38 TWh frente a una demanda total de 316,55 TWh, lo que supone un excesivo porcentaje de vertidos. Los resultados obtenidos también han mostrado que la única forma de poder obtener un mix eléctrico 100% renovable en 2050 sin unos excesivos vertidos sería disponer de tecnologías competitivas de almacenamiento y gestión a gran escala de la electricidad excedente, porque esto permitiría reducir de forma muy importante la potencia instalada de fotovoltaica, eólica y termosolar, consiguiéndose menores costes de la electricidad y menores vertidos.ABSTRACT: This paper shows a summary of the results obtained when analysing how the Spanish electricity mix must evolve during next 30 years to fulfil two different scenarios of CO2 emissions reduction in comparison with those in 1990. A multi-objective genetic algorithm has been used to perform the study. Two different scenarios have been analysed: 1) moderate trend of 40% (2030), 60% (2040) y 80% (2050) reduction; 2) aggressive trend of 50% (2030), 75% (2040) and 100% (2050). Results given in this paper show that the moderate trend is feasible regarding both the electricity cost and the curtailments. A reduction of 80% in 2050 would require an 86.34% renewable electricity market with an electricity cost of 47,4 €/MWh. On the other hand, for the fulfilment of the aggressive trend (no CO2 emissions in 2050) the electricity cost and the curtailments would be 62,9 €/MWh and 222,38 TWh, respectively, with a total electricity demand of only 316,55 TWh. This level of curtailments is clearly excessive. The obtained results have also shown that the only way to achieve a 100% renewable electricity market in Spain in 2050 without excessive curtailments would be the use of cost-effective electricity storage technologies because they would allow a significant reduction of the required installed power of photovoltaic, wind and solar thermal electricity plants, while reducing the electricity cost and the curtailments simultaneously.info:eu-repo/semantics/publishedVersio
Crisis due to war: anxiety, depression and stress in the population of 13 Latin American countries
Sustainability may be at risk in a population that has altered health, according to Sustainable Development Goal 3 (SDG 3): Health and well-being. The ongoing conflict between Russia and Ukraine could jeopardize SDG 3, specifically the mental health of the population. The present study sought to determine the association between severe anxiety, depression and stress in population of 13 Latin American countries according to fear about the war conflict. It was a cross-sectional, analytical and multicenter study. Anxiety, depression and stress were measured with the DASS-21 test (Cronbach’s Alpha: 0.97) and fear due to an armed crisis with a questionnaire already validated in Latin America (Cronbach’s Alpha: 0.92), which was also adjusted for sex, age, education level and country of residence. Descriptive and analytical statistics were obtained. Of the 2,626 respondents, the main fear was that weapons of mass destruction would be used. In the multivariate models, strong associations were found between fear of a possible world-scale armed conflict and having severe or very severe levels of anxiety (aPR: 1.97; 95% CI: 1.64–2.36; value of p <0.001), depression (aPR: 1.91; 95% CI: 1.54–2.36; value of p <0.001) or stress (aPR: 2.05; 95% CI: 1.63–2.57; value of p <0.001). Sustainability linked to SDG 3, specifically mental health, is affected by this type of significant events, given the possible global war crisis that could trigger major events, even more so if added to the deterioration already experienced by COVID-19 in the Latin American region, insecurity and constant political uncertainty
Target product profile for a test for the early assessment of treatment efficacy in Chagas disease patients: An expert consensus.
Six to 7 million people are estimated to be infected by Trypanosoma cruzi, the parasite causing Chagas disease. Thirty to 40% of them, i.e., 1.8 to 2.4 million people, will suffer cardiac disorders and/or digestive clinical manifestations if they are not treated early during the course of the infection [1, 2]. However, only a small fraction of patients are properly diagnosed and treated [3]. Current clinical guidelines recommend treating T. cruzi–infected people if they are asymptomatic or present early symptoms of the disease (Table 1) [4, 5]. Benznidazole (BNZ) and nifurtimox (NFX) are the first-line antiparasitic treatments currently available, both with long administration regimens (60 days) that can produce adverse side effects [6–8]. Despite the fact they are not 100% effective in patients with chronic disease [9–12], they are the only drugs currently registered, and the benefits of their administration have been confirmed in several clinical studies. Currently, clinical trials with new compounds, using alternative regimens that aim to maintain efficacy whilst reducing toxicity, are ongoing and could lead to new therapeutic opportunities and/or policy change
It's all about the children: a participant-driven photo-elicitation study of Mexican-origin mothers' food choices
Abstract Background There is a desperate need to address diet-related chronic diseases in Mexican-origin women, particularly for those in border region colonias (Mexican settlements) and other new destination communities in rural and non-rural areas of the U.S. Understanding the food choices of mothers, who lead food and health activities in their families, provides one way to improve health outcomes in Mexican-origin women and their children. This study used a visual method, participant-driven photo-elicitation, and grounded theory in a contextual study of food choices from the perspectives of Mexican-origin mothers. Methods Teams of trained promotoras (female community health workers from the area) collected all data in Spanish. Ten Mexican-origin mothers living in colonias in Hidalgo County, TX completed a creative photography assignment and an in-depth interview using their photographs as visual prompts and examples. English transcripts were coded inductively by hand, and initial observations emphasized the salience of mothers' food practices in their routine care-giving. This was explored further by coding transcripts in the qualitative data analysis software Atlas.ti. Results An inductive conceptual framework was created to provide context for understanding mothers' daily practices and their food practices in particular. Three themes emerged from the data: 1) a mother's primary orientation was toward her children; 2) leveraging resources to provide the best for her children; and 3) a mother's daily food practices kept her children happy, healthy, and well-fed. Results offer insight into the intricate meanings embedded in Mexican-origin mothers' routine food choices. Conclusions This paper provides a new perspective for understanding food choice through the eyes of mothers living in the colonias of South Texas -- one that emphasizes the importance of children in their routine food practices and the resilience of the mothers themselves. Additional research is needed to better understand mothers' perspectives and food practices with larger samples of women and among other socioeconomic groups
Neuroimmunological findings of Angiostrongylus cantonensis meningitis in ecuadorian patients
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