Ecohydrology of aspen and eucalyptus plantations: considerations for management

Forecast scenarios predict an increase in the demand of alternative sources of energy during the coming decades, such as woody biomass crops (WBC). WBC have the potential to become a major challenge for the next generation of researchers, policymakers and land managers. However, the current rationale for promoting plant-based over petroleum-based energy sources emphasizes the benefits of reduced carbon dioxide and other emissions, while giving less attention to potential impacts to water resources. It is well documented in the scientific literature that trees use large amounts of water for metabolic needs. Water use at the tree and ecosystem level has always been of scientific interest, however, the potential impact of water use in bioenergy plantations is often considered a “possible environmental impact”. Thus, understanding the ecological implications of water use in WBC is essential for their sustainable development. The general goal of my research was to assess potential ecohydrological impacts associated with the production of biomass for bioenergy from aspen (Populus tremuloides Mich.) in Wisconsin, USA, and eucalyptus (Eucalyptus grandis) plantations in Entre Rios, Argentina. My doctoral research was part of a large international interdisciplinary NSF-PIRE research project that examined the impacts, barriers and opportunities related to bioenergy production across the Americas (USA, Mexico, Brazil, Argentina). We selected plantation ages within the most common rotation cycles for each species. In Wisconsin, we studied three sites, a 10- and a 24-year-old (YO) coppice plantations, and a reference 34 YO mature forest. In Argentina, we studied two 1 YO plantations one at high and one at regular density, a 4 YO, a 10 YO plantation, and a reference grassland. This was a unique study to determine annual water use based on a combination of tree-level measurements of water use using sap flow sensors, and deterministic models of potential evapotranspiration. We validated two sap flow methods (heat dissipation and heat ratio), and validated a third method (maximum heat ratio) that is capable of measuring with precision high and low sap flux densities (Fd, cm3 cm-2 cm1). According to the results from the validation studies, we were able to estimate tree-level water use within a 7% error margin (estimated as the difference between observed and estimated sap flow in L h-1) using heat ratio and maximum heat ratio methods, without generating species-specific parameters. However, using the heat dissipation method, the average estimation error without species-specific parameters was -53%, and improved to 5% once species-specific parameters were generated. Validating the maximum heat ratio method, allowed us to estimate Fd in young trees, which are often excluded from chronosequence studies due to their high Fd. Our estimates of Fd at different plantation ages, allowed us to extrapolate from the tree to the site level, using real tree-level response to various environmental variables. Our analysis of P. tremuloides and E. grandis offered contrasting results. In P. tremuloides plantations, water use at the site level generally increased with age, even when site density decreased over time (from approx. 6500 to 1900 from 10 to 34 YO). We observed that young plantations (10 YO) used 80% of the annual water early in the growing season, compared to a 45% for the same period in the Mid-aged and Mature plantations. Site effects, specifically soil type and the resulting soil saturation (S), had a significant effect on T estimates. After modeling the effects of S, creating two artificial scenarios (e.g. limited and non-limited S) the 10 YO site showed the highest sensibility to changes in S, while the 34 YO mature site was the least affected. Average stand transpiration by site considering the effects of S increased with age, which supported our hypothesis regarding the relationship between stand age and stand T. However, the relationship between stand T was not constant across seasons, which according to our results might be caused by a higher hydraulic stress observed in the 10YO site, compared to the other two sites. On eucalyptus plantations, when the density remained constant, stand T decreased with plantation age, reaching maximum water use rates at around 4 YO and declining afterwards for the remainder of the typical 15 YO rotation cycles. Due to similar site conditions in terms of soil characteristics, we did not observe a strong site effect. Our experimental site at high density (e.g., double of a regular site) showed an increase in average site T of 50%, and both 1 YO sites presented an opportunistic pattern in water use, increasing when soil water was available, but decreasing significantly when soil moisture was limiting. Finally, in both plantations we observed that reference evapotranspiration, estimated with the Penman-Monteith equation, was a poor predictor of water use in young plantations. We associate these results to the seasonal patterns of water use in young plantations. Within the context of bioenergy production, our results provide ample evidence for the importance of water use in bioenergy plantations in the early stages of feedstock production. We also show that plantation density in fast and slow growing species, impacts the way trees respond to water availability in the soil

The contribution of the United States Supreme Court and the European Court of justice in the vertical and horizontal allocation of power

PhDThis thesis explores the contribution of the US Supreme Court (USSC) and the European Court of Justice (ECJ) in the vertical and horizontal allocation of power. Said differently, it answers the two following questions: How do both Courts draw the line between the realm of politics and judicial process? How do they allocate power between the Union and its component States? After examining standing, the political question doctrine, negative and positive integration and liability in damages on both sides of the Atlantic, it is concluded that both Courts should not always look for “substantive” constitutional benchmarks. The reason lies in that sometimes the latter may turn to be either questions deemed too political for judicial resolution or insufficient to control congressional or Community legislative powers. Additionally, the judicial department should also pay due regard to a “process” review. This type of review would operate at two levels. At first stage, Courts should solve flaws in the procedure by which the political institutions adopt their decisions. For instance, this would be the case where procedures neglect “discrete and insular” minorities, or where they entrench incumbent political majorities. Thus, judicial review would be principled upon understanding “democracy” as an intangible value that cannot succumb to majoritarian pressures. At a second stage, Courts should also examine whether, in their deliberations, political actors pay due account to all interests at stake, particularly, to those not represented in the political process

Persistent homology for 3D reconstruction evaluation

Space or voxel carving is a non-invasive technique that is used to produce a 3D volume and can be used in particular for the reconstruction of a 3D human model from images captured from a set of cameras placed around the subject. In [1], the authors present a technique to quantitatively evaluate spatially carved volumetric representations of humans using a synthetic dataset of typical sports motion in a tennis court scenario, with regard to the number of cameras used. In this paper, we compute persistent homology over the sequence of chain complexes obtained from the 3D outcomes with increasing number of cameras. This allows us to analyze the topological evolution of the reconstruction process, something which as far as we are aware has not been investigated to date

Toxoplasma gondii and Schizophrenia: A Relationship That Is Not Ruled Out

Over recent years, it has been proposed that some diseases of unknown origin, such as schizophrenia, may be caused by persistent chronic infections coupled with a genetic component and may be perpetuated by the immune system. This hypothesis is supported by epidemiological and biological evidence on the exposure of schizophrenics to infectious diseases during prenatal or postnatal periods, including Toxoplasma gondii, chlamydia, human herpes virus, human endogenous retroviruses, parvovirus B19, mumps, and flu viruses. This growing list of microbes will undoubtedly continue to increase in the future. Linking infection to schizophrenia is a complex challenge that requires further experimental and epidemiological research. T. gondii is the infectious agent that has most frequently been related to neuropsychiatric disorders, including schizophrenia, and it is considered to represent a highly useful model to analyze the influence of a microorganism on human behavior and the development of psychiatric disease. It may also help to detect patient subpopulations susceptible to treatment with specific antimicrobials by improving definition of the differential phenotype of the disease, and it offers the possibility of a preventive approach

Particle methods parallel implementations by GP-GPU strategies

This paper outlines the problems found in the parallelization of SPH (Smoothed Particle Hydrodynamics) algorithms using Graphics Processing Units. Different results of some parallel GPU implementations in terms of the speed-up and the scalability compared to the CPU sequential codes are shown. The most problematic stage in the GPU-SPH algorithms is the one responsible for locating neighboring particles and building the vectors where this information is stored, since these specific algorithms raise many dificulties for a data-level parallelization. Because of the fact that the neighbor location using linked lists does not show enough data-level parallelism, two new approaches have been pro- posed to minimize bank conflicts in the writing and subsequent reading of the neighbor lists. The first strategy proposes an efficient coordination between CPU-GPU, using GPU algorithms for those stages that allow a straight forward parallelization, and sequential CPU algorithms for those instructions that involve some kind of vector reduction. This coordination provides a relatively orderly reading of the neighbor lists in the interactions stage, achieving a speed-up factor of x47 in this stage. However, since the construction of the neighbor lists is quite expensive, it is achieved an overall speed-up of x41. The second strategy seeks to maximize the use of the GPU in the neighbor's location process by executing a specific vector sorting algorithm that allows some data-level parallelism. Al- though this strategy has succeeded in improving the speed-up on the stage of neighboring location, the global speed-up on the interactions stage falls, due to inefficient reading of the neighbor vectors. Some changes to these strategies are proposed, aimed at maximizing the computational load of the GPU and using the GPU texture-units, in order to reach the maximum speed-up for such codes. Different practical applications have been added to the mentioned GPU codes. First, the classical dam-break problem is studied. Second, the wave impact of the sloshing fluid contained in LNG vessel tanks is also simulated as a practical example of particle method

Análisis de la contratación laboral y despidos laborales en Instituciones Públicas Arequipa 2021

El presente Informe de investigación, “Análisis de la contratación laboral y despidos laborales en instituciones públicas, Arequipa, 2021”, tiene como objetivo, Analizar la contratación laboral y los despidos laborales en instituciones públicas, Arequipa, 2021. Metodología: El tipo de investigación será el básico debido a que se contará con la predisposición de analizar un determinado contexto con base en comprender una determinada, el enfoque con el que se contará será el cualitativo, con diseño será el descriptivo, transversal y no experimental. Resultados: El Tribunal Constitucional el dar una interpretación de la Constitución Política, este avala los derechos y a la vez garantiza la protección a aquellos trabajadores que estén siendo afectados por un despido laboral, en la actualidad no es necesario acudir hasta el TC para que se avale dicha protección

Gestión del servicio de inmunización Covid-19 y calidad de atención de un centro materno infantil en Apurímac – 2022

Este trabajo se desarrolló para determinar el objetivo de relación entre gestión del servicio de inmunización Covid-19 y calidad de atención de un centro materno infantil Apurímac- 2022. La investigación es de tipo básico, diseño no experimental, corte transversal, carácter descriptivo, correlacional, aplicándose a 89 trabajadores de un centro materno infantil en Apurímac, la encuesta fue la técnica de recolección de datos, los instrumentos fueron dos cuestionarios de 30 y 20 items para las variables de gestión del servicio de inmunización y calidad de atención, los resultados hallados fueron que la correlación adquiere un grado positivo y significativo de las variables, el resultado que respalda es la prueba estadística de Rho de Spearman con r=0.735, determinando la existencia de asociación significativa entre estas variables y una significancia bilateral de 0.000<0.05, de esta manera aceptando la hipótesis alterna y rechazando la hipótesis nula, concluyendo finalmente en un 75.3% de trabajadores califican a la variable de gestión del servicio de inmunización con el nivel regular, mientras que para la variable calidad de atención un 78.7% lo califica en el nivel regular, concluyendo que el nivel de gestión de servicios de inmunización y calidad de atención en el centro materno infantil es regular

Finanzas Empresariales: Valuacion de Obligaciones y Acciones

Antes del año de 1994 el mercado de valores de bonos y acciones era una inversión que prometía al inversionista un rendimiento aceptable a todos los que se propusieron invertir en obligaciones financieras (bonos y acciones), por lo tanto ciertos inversionistas que hubieran comprado un bono o acción un año antes pudieron haber incurrido en pérdidas en su capital. A través de esta información se plantea, ¿Por qué generaba perdidas invertir en obligaciones financieras antes de 1994? La razón fundamental por la que el valor de esta inversión y así como de otros instrumentos de endeudamiento disminuyó en forma significativa fue porque la reserva federal internacional decidió incrementar la tasa de interés 6 veces más durante 1994 de tal manera que, en un solo año el rendimiento exigido por los inversionistas aumento en más del 2%. Como consecuencia de este incremento en las tasas de interés el valor de los instrumentos financieros disminuyó en forma notable. Por ejemplo: un bono que tenía un valor de $10,000 al 3 de enero de 1994, al 3 de enero de 1995 su valor era de aproximadamente de$8,910, por lo tanto, si usted hubiera comprado este bono un año antes por lo menos, en papel, habrían incurrido en una pérdida de $1,090 durante 1994. A medida que usted lea este documento, piense en la razón por la cual el valor de los bonos de la tesorería disminuyó en forma significativa desde enero de 1994 a enero de 1995, cuando las tasas de interés aumentaron más del 2%. ¿Qué le sucede al valor de los activos financieros cuando cambian los rendimientos exigidos por los inversionistas? La respuesta a esta pregunta le ayudara a obtener una comprensión básica de la manera como los bonos y acciones se valúan en los mercados financieros. Además que todas la información necesaria para tener una mejor comprensión acerca de los bonos y acciones y su mercado de desarrollo las encontrará a lo largo de esta investigación documental