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Thermokinetics of Biochar production.

Treball final de Grau en Psicologia. Codi: PS1048. Curs acadèmic 2015-2016 El estresante estilo de vida de la sociedad actual junto con la mala concepción sobre las posibles consecuencias del consumo de alcohol podrían ser algunas de las causas de que actualmente el alcohol sea una de las drogas más consumidas a nivel mundial según la OMS. Sin embargo, a pesar de todos los avances de la neurociencia, el mecanismo exacto de cómo actúa el alcohol en el SNC nos es aún desconocido. El objetivo de este trabajo es tratar de plantear y dar pruebas a favor de una hipótesis sobre como podría actuar realmente el alcohol en el cerebro. El método de este trabajo consta del análisis de 4 estudios que muestran las manipulaciones de diferentes mediadores de calcio y AMPc-­‐PKA y las consecuencias de esas manipulaciones a nivel molecular, celular, neurobiológico y conductual. Por una parte los resultados obtenidos nos muestran que posiblemente, estos mediadores de calcio tengan una función muy importantes a la hora de explicar el mecanismo de acción del alcohol en el cerebro. Pero, no obstante, no son suficientes evidencias como para afirmar con completa claridad y certeza que este sea el mecanismo exacto de actuación del alcohol en el SNC. The stressfull way of life of our nowadays society in adition to the missconception of the potencial consequences from alcohol consum could be some of the reasons for why alcohol is the worldwide most consumed drug according to OMS. However, besides all the neuroscience developments, the true mechanism of alcohol functionament on the SNC has been not proved. The method of this paper consists of the analysis of 4 studies that show the manipulations of the different mediators of calcium and cAMP-­‐PKA and the consequences of these manipulations at a molecular, cellular, neurobiological and behavioural level. The results, in one hand, show that is possible that those mediators of calcium are important for understands the true mechanism of how alcohol works in the brain. However, there are no enough evidences to completely agree that this is the exact mechanism by which alcohol acts at a central level.

As it becomes clear that climate change is not easily within the boundaries of the 1990's, society needs to be prepared and needs to anticipate future changes due to the uncertain changes in climate. So far, extensive research has been carried out on several issues including the coastal defence or shifting ecozones. However, the role spatial design and planning can play in adapting to climate change has not yet been focussed on.This book illuminates the way adaptation to climate change is tackled in water management, ecology, coastal defence, the urban environment and energy. The question posed is how each sector can anticipate climate change by creating spatial designs and plans. The main message of this book is that spatial design and planning are a very useful tool in adapting to climate change. It offers an integral view on the issue, it is capable in dealing with uncertainties and it opens the way to creative and anticipative solutions. Dealing with adaptation to climate change requires a shift in mindset; from a technical rational way of thinking towards an integral proactive one. A new era in spatial design and planning looms on the horizon. © Springer Science+Business Media B.V. 2009.

The potential for global forest cover The restoration of forested land at a global scale could help capture atmospheric carbon and mitigate climate change. Bastin et al. used direct measurements of forest cover to generate a model of forest restoration potential across the globe (see the Perspective by Chazdon and Brancalion). Their spatially explicit maps show how much additional tree cover could exist outside of existing forests and agricultural and urban land. Ecosystems could support an additional 0.9 billion hectares of continuous forest. This would represent a greater than 25% increase in forested area, including more than 200 gigatonnes of additional carbon at maturity.Such a change has the potential to store an equivalent of 25% of the current atmospheric carbon pool. Science , this issue p. 76 ; see also p. 24

Artículos en revistas Numerical models of transmission-constrained electricity markets are used to inform regulatory decisions. How robust are their results? Three research groups used the same data set for the northwest Europe power market as input for their models. Under competitive conditions, the results coincide, but in the Cournot case, the predicted prices differed significantly. The Cournot equilibria are highly sensitive to assumptions about market design (whether timing of generation and transmission decisions is sequential or integrated) and expectations of generators regarding how their decisions affect transmission prices and fringe generation. These sensitivities are qualitatively similar to those predicted by a simple two-node model. info:eu-repo/semantics/publishedVersion

Abstract The organic Rankine cycle (ORC) has been growing in importance as a technology for producing electricity from low temperature waste and renewable heat sources. In small-scale applications, the most used working fluid has been HFC-245fa, although this is being substituted for low GWP alternatives. A new HCFO working fluid, HCFO-1224yd(Z), has appeared as a possible alternative for HFC-245fa. In this study, this alternative working fluid is analysed and, finally, the working fluid is experimentally tested as drop-in alternative in a commercial ORC system. The main purpose is to determine the feasibility of using HCFO-1224yd(Z) as a drop-in replacement for HFC-245fa in a real facility that was initially designed to operate with HFC-245fa. The results show how the use of HCFO-1224yd(Z) offers power output that ranges from 7.5% to 17.4% lower than that provided by HFC-245fa. Although HFC-245fa offers higher power output, the results show that HCFO-1224yd(Z) offers up to 7.7% higher cycle net efficiency; this is due to the higher input thermal rate required by HFC-245fa. Finally, HCFO-1224yd(Z) has been stated as a suitable alternative to HFC-245fa as a drop-in replacement in a small-scale, low-temperature ORC, which increases its attractiveness for heat source with higher temperatures.

Abstract Both steady-state AC and DC power flow models are commonly used for techno-economic studies of power systems. The DC-based approach limits the computational burden by assuming small-angle approximation, ignoring power losses, reactive power flows, and voltage variations. It, therefore, matters to understand if this approach affects system vulnerability, reliability, and contingency assessments. To this aim, we use the time-sequential Monte Carlo simulation and an N-k′-1 scenario for reliability and contingency analyses, respectively. Further, we introduce a new index for vulnerability assessment. The IEEE reliability test system (RTS) and the modified RTS are modeled. The results show that the DC model underestimates the reliability indices by about 20% and more than 90% in a stressed network. We also show a small error of 5%, owing to the assumptions of the DC model, which can lead to inaccurate simulations concerning the cascading failures. Finally, the sources of the inaccuracy in the DC-based model are investigated. The results prove that AC power flow model should be privileged for the line capacity-based assessments.

AbstractAlthough canopy height has long been a focus of interest in ecology, it has remained difficult to study at large spatial scales. Recently, satellite‐borne LiDAR equipment produced the first systematic high resolution maps of vegetation height worldwide. Here we show that this new resource reveals three marked modes in tropical canopy height ~40, ~12, and ~2 m corresponding to forest, savanna, and treeless landscapes. The distribution of these modes is consistent with the often hypothesized forest‐savanna bistability and suggests that both states can be stable in areas with a mean annual precipitation between ~1,500 and ~2,000 mm. Although the canopy height states correspond largely to the much discussed tree cover states, there are differences, too. For instance, there are places with savanna‐like sparse tree cover that have a forest‐like high canopy, suggesting that rather than true savanna, those are thinned relicts of forest. This illustrates how complementary sets of remotely sensed indicators may provide increasingly sophisticated ways to study ecological phenomena at a global scale.