912 resultados para 2016 Crop Condition
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I report the solubility and diffusivity of water in lunar basalt and an iron-free basaltic analogue at 1 atm and 1350 °C. Such parameters are critical for understanding the degassing histories of lunar pyroclastic glasses. Solubility experiments have been conducted over a range of fO2 conditions from three log units below to five log units above the iron-wüstite buffer (IW) and over a range of pH2/pH2O from 0.03 to 24. Quenched experimental glasses were analyzed by Fourier transform infrared spectroscopy (FTIR) and secondary ionization mass spectrometry (SIMS) and were found to contain up to ~420 ppm water. Results demonstrate that, under the conditions of our experiments: (1) hydroxyl is the only H-bearing species detected by FTIR; (2) the solubility of water is proportional to the square root of pH2O in the furnace atmosphere and is independent of fO2 and pH2/pH2O; (3) the solubility of water is very similar in both melt compositions; (4) the concentration of H2 in our iron-free experiments is <3 ppm, even at oxygen fugacities as low as IW-2.3 and pH2/pH2O as high as 24; and (5) SIMS analyses of water in iron-rich glasses equilibrated under variable fO2 conditions can be strongly influenced by matrix effects, even when the concentrations of water in the glasses are low. Our results can be used to constrain the entrapment pressure of the lunar melt inclusions of Hauri et al. (2011).
Diffusion experiments were conducted over a range of fO2 conditions from IW-2.2 to IW+6.7 and over a range of pH2/pH2O from nominally zero to ~10. The water concentrations measured in our quenched experimental glasses by SIMS and FTIR vary from a few ppm to ~430 ppm. Water concentration gradients are well described by models in which the diffusivity of water (D*water) is assumed to be constant. The relationship between D*water and water concentration is well described by a modified speciation model (Ni et al. 2012) in which both molecular water and hydroxyl are allowed to diffuse. The success of this modified speciation model for describing our results suggests that we have resolved the diffusivity of hydroxyl in basaltic melt for the first time. Best-fit values of D*water for our experiments on lunar basalt vary within a factor of ~2 over a range of pH2/pH2O from 0.007 to 9.7, a range of fO2 from IW-2.2 to IW+4.9, and a water concentration range from ~80 ppm to ~280 ppm. The relative insensitivity of our best-fit values of D*water to variations in pH2 suggests that H2 diffusion was not significant during degassing of the lunar glasses of Saal et al. (2008). D*water during dehydration and hydration in H2/CO2 gas mixtures are approximately the same, which supports an equilibrium boundary condition for these experiments. However, dehydration experiments into CO2 and CO/CO2 gas mixtures leave some scope for the importance of kinetics during dehydration into H-free environments. The value of D*water chosen by Saal et al. (2008) for modeling the diffusive degassing of the lunar volcanic glasses is within a factor of three of our measured value in our lunar basaltic melt at 1350 °C.
In Chapter 4 of this thesis, I document significant zonation in major, minor, trace, and volatile elements in naturally glassy olivine-hosted melt inclusions from the Siqueiros Fracture Zone and the Galapagos Islands. Components with a higher concentration in the host olivine than in the melt (MgO, FeO, Cr2O3, and MnO) are depleted at the edges of the zoned melt inclusions relative to their centers, whereas except for CaO, H2O, and F, components with a lower concentration in the host olivine than in the melt (Al2O3, SiO2, Na2O, K2O, TiO2, S, and Cl) are enriched near the melt inclusion edges. This zonation is due to formation of an olivine-depleted boundary layer in the adjacent melt in response to cooling and crystallization of olivine on the walls of the melt inclusions concurrent with diffusive propagation of the boundary layer toward the inclusion center.
Concentration profiles of some components in the melt inclusions exhibit multicomponent diffusion effects such as uphill diffusion (CaO, FeO) or slowing of the diffusion of typically rapidly diffusing components (Na2O, K2O) by coupling to slow diffusing components such as SiO2 and Al2O3. Concentrations of H2O and F decrease towards the edges of some of the Siqueiros melt inclusions, suggesting either that these components have been lost from the inclusions into the host olivine late in their cooling histories and/or that these components are exhibiting multicomponent diffusion effects.
A model has been developed of the time-dependent evolution of MgO concentration profiles in melt inclusions due to simultaneous depletion of MgO at the inclusion walls due to olivine growth and diffusion of MgO in the melt inclusions in response to this depletion. Observed concentration profiles were fit to this model to constrain their thermal histories. Cooling rates determined by a single-stage linear cooling model are 150–13,000 °C hr-1 from the liquidus down to ~1000 °C, consistent with previously determined cooling rates for basaltic glasses; compositional trends with melt inclusion size observed in the Siqueiros melt inclusions are described well by this simple single-stage linear cooling model. Despite the overall success of the modeling of MgO concentration profiles using a single-stage cooling history, MgO concentration profiles in some melt inclusions are better fit by a two-stage cooling history with a slower-cooling first stage followed by a faster-cooling second stage; the inferred total duration of cooling from the liquidus down to ~1000 °C is 40 s to just over one hour.
Based on our observations and models, compositions of zoned melt inclusions (even if measured at the centers of the inclusions) will typically have been diffusively fractionated relative to the initially trapped melt; for such inclusions, the initial composition cannot be simply reconstructed based on olivine-addition calculations, so caution should be exercised in application of such reconstructions to correct for post-entrapment crystallization of olivine on inclusion walls. Off-center analyses of a melt inclusion can also give results significantly fractionated relative to simple olivine crystallization.
All melt inclusions from the Siqueiros and Galapagos sample suites exhibit zoning profiles, and this feature may be nearly universal in glassy, olivine-hosted inclusions. If so, zoning profiles in melt inclusions could be widely useful to constrain late-stage syneruptive processes and as natural diffusion experiments.
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The purpose of this thesis is to characterize the behavior of the smallest turbulent scales in high Karlovitz number (Ka) premixed flames. These scales are particularly important in the two-way coupling between turbulence and chemistry and better understanding of these scales will support future modeling efforts using large eddy simulations (LES). The smallest turbulent scales are studied by considering the vorticity vector, ω, and its transport equation.
Due to the complexity of turbulent combustion introduced by the wide range of length and time scales, the two-dimensional vortex-flame interaction is first studied as a simplified test case. Numerical and analytical techniques are used to discern the dominate transport terms and their effects on vorticity based on the initial size and strength of the vortex. This description of the effects of the flame on a vortex provides a foundation for investigating vorticity in turbulent combustion.
Subsequently, enstrophy, ω2 = ω • ω, and its transport equation are investigated in premixed turbulent combustion. For this purpose, a series of direct numerical simulations (DNS) of premixed n-heptane/air flames are performed, the conditions of which span a wide range of unburnt Karlovitz numbers and turbulent Reynolds numbers. Theoretical scaling analysis along with the DNS results support that, at high Karlovitz number, enstrophy transport is controlled by the viscous dissipation and vortex stretching/production terms. As a result, vorticity scales throughout the flame with the inverse of the Kolmogorov time scale, τη, just as in homogeneous isotropic turbulence. As τη is only a function of the viscosity and dissipation rate, this supports the validity of Kolmogorov’s first similarity hypothesis for sufficiently high Ka numbers (Ka ≳ 100). These conclusions are in contrast to low Karlovitz number behavior, where dilatation and baroclinic torque have a significant impact on vorticity within the flame. Results are unaffected by the transport model, chemical model, turbulent Reynolds number, and lastly the physical configuration.
Next, the isotropy of vorticity is assessed. It is found that given a sufficiently large value of the Karlovitz number (Ka ≳ 100) the vorticity is isotropic. At lower Karlovitz numbers, anisotropy develops due to the effects of the flame on the vortex stretching/production term. In this case, the local dynamics of vorticity in the strain-rate tensor, S, eigenframe are altered by the flame. At sufficiently high Karlovitz numbers, the dynamics of vorticity in this eigenframe resemble that of homogeneous isotropic turbulence.
Combined, the results of this thesis support that both the magnitude and orientation of vorticity resemble the behavior of homogeneous isotropic turbulence, given a sufficiently high Karlovitz number (Ka ≳ 100). This supports the validity of Kolmogorov’s first similarity hypothesis and the hypothesis of local isotropy under these condition. However, dramatically different behavior is found at lower Karlovitz numbers. These conclusions provides/suggests directions for modeling high Karlovitz number premixed flames using LES. With more accurate models, the design of aircraft combustors and other combustion based devices may better mitigate the detrimental effects of combustion, from reducing CO2 and soot production to increasing engine efficiency.
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A cidade do Rio de Janeiro foi eleita sede dos Jogos Olímpicos e Paraolímpicos de 2016 e são previstos impactos significativos em investimento e na geração de emprego, atrelados a isto existe a preocupação com as questões ambientais e a sustentabilidade do evento. No dossiê de candidatura do Rio de Janeiro a sede dos Jogos Olímpicos de 2016, existia o compromisso com a gestão dos resíduos sólidos. As grandes linhas de ações foram definidas quando do lançamento da candidatura do Rio de Janeiro a sede do evento, fato este que se concretizou em 02 de outubro de 2009. A gestão dos resíduos para 2016 é ainda carente de informações quantitativas de sua geração, das necessidades de adaptações das instalações para o período de realização do evento, bem como da definição de metas para que a gestão dos resíduos devidamente alinhadas com os preceitos do desenvolvimento sustentável. O objetivo deste estudo é avaliar sub o conceito de desenvolvimento sustentável a gestão de resíduos sólidos durante a realização dos Jogos Olímpicos de 2016 na cidade do Rio de Janeiro. A metodologia consiste no levantamento histórico dos Jogos Olímpicos com especial detalhamento nas questões ligadas ao conceito de desenvolvimento sustentável e gestão de resíduos, análise dos Jogos Pan-americanos do Rio de Janeiro, levantamento em campo da preparação dos Jogos Olímpicos de Londres, observações em campo na cidade do Rio de Janeiro e a análise de dados para o cálculo da estimativa de geração de resíduos durante a realização dos Jogos de 2016. As comparações com outros eventos demonstraram semelhanças e diferenças com os Jogos Olímpicos de 2016 e possibilitou a apresentação de proposições para a gestão de resíduos sólidos. A projeção de geração de resíduos durante o evento é significativa e aponta a necessita de atenção para potencializar as ações como coleta seletiva, reciclagem e compostagem. São indicados estudos futuros sobre a gestão dos resíduos, em especial da construção civil durante as obras das futuras instalações, algumas delas já em curso.
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Chronic obstructive pulmonary disease (COPD) is a complex and heterogeneous condition characterized by occasional exacerbations. Identifying clinical subtypes among patients experiencing COPD exacerbations (ECOPD) could help better understand the pathophysiologic mechanisms involved in exacerbations, establish different strategies of treatment, and improve the process of care and patient prognosis. The objective of this study was to identify subtypes of ECOPD patients attending emergency departments using clinical variables and to validate the results using several outcomes. We evaluated data collected as part of the IRYSS-COPD prospective cohort study conducted in 16 hospitals in Spain. Variables collected from ECOPD patients attending one of the emergency departments included arterial blood gases, presence of comorbidities, previous COPD treatment, baseline severity of COPD, and previous hospitalizations for ECOPD. Patient subtypes were identified by combining results from multiple correspondence analysis and cluster analysis. Results were validated using key outcomes of ECOPD evolution. Four ECOPD subtypes were identified based on the severity of the current exacerbation and general health status (largely a function of comorbidities): subtype A (n = 934), neither high comorbidity nor severe exacerbation; subtype B (n = 682), moderate comorbidities; subtype C (n = 562), severe comorbidities related to mortality; and subtype D (n = 309), very severe process of exacerbation, significantly related to mortality and admission to an intensive care unit. Subtype D experienced the highest rate of mortality, admission to an intensive care unit and need for noninvasive mechanical ventilation, followed by subtype C. Subtypes A and B were primarily related to other serious complications. Hospitalization rate was more than 50% for all the subtypes, although significantly higher for subtypes C and D than for subtypes A and B. These results could help identify characteristics to categorize ECOPD patients for more appropriate care, and help test interventions and treatments in subgroups with poor evolution and outcomes.
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Getariako itsas kirol etxearen proiektua Getarian malkorbe izeneko hondartzan ur kirol ezberdinak egiteko aukera mundu guztiaren eskura egotea eta horrez gain turismo aktiboaren parte eta hondartzaren erabilera udarara bakarrik ez mugatzea datza
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Azken urteetan, Zaztaparrak asti taldea Arratia eta Zeberio lurraldeetako aisialdian liderra bilakatu da, izan ere, arlo honi dagozkion lan-esparru gehienetan (udalekuak, ludotekak, gazte espazio ezberdinak…) indar gehien duen elkartea da. Egoera honek, helburu berriak amestea ahalbidetu dio elkarteari eta, horrela, asmo handiko proiektuak aurrera eramateko aukera sortu da. Horretarako, txosten honen bitartez, Zaztaparrak asti taldearen plan estrategikoa aurkezten da, hurrengo urteetan izan beharreko jokabidea eta programazioa aurkezten duena alegia. Plan honen bitartez, jarduera fisikoaren promozioa helburu izanik, elkarteak, aisialdi aktiboago bat bultzatzen du. Helburu honek, turismo aktiboaren esparruko enpresekin komunikazio kanalak osatzea bilatzen du eta horrela, eskaintza aktibo horren parte bilakatzera eramango du. Horretaz guztiaz gainera, bere ekintza eremua Euskal Herri osora zabaltzea bilatzen du, izan ere, elkartea sortzerakoan Arratiako bailaran zeuden beharrak gure herrialdeko beste hainbat txokotan ere aurkitzen dira eta, horrela, Zaztaparrak asti taldeak aisialdi elkarte ezberdinen elkarlana koordinatzea du helburu. Hala, jarraian, elkarteak eman nahi duen salto kualitatibo hau bideratuko duen plan estrategikoa aurkezten da.
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La salud es un aspecto muy importante en la vida de cualquier persona, de forma que, al ocurrir cualquier contingencia que merma el estado de salud de un individuo o grupo de personas, se debe valorar estrictamente y en detalle las distintas alternativas destinadas a combatir la enfermedad. Esto se debe a que, la calidad de vida de los pacientes variará dependiendo de la alternativa elegida. La calidad de vida relacionada con la salud (CVRS) se entiende como el valor asignado a la duración de la vida, modificado por la oportunidad social, la percepción, el estado funcional y la disminución provocadas por una enfermedad, accidente, tratamiento o política (Sacristán et al, 1995). Para determinar el valor numérico asignado a la CVRS, ante una intervención, debemos beber de la teoría económica aplicada a las evaluaciones sanitarias para nuevas intervenciones. Entre los métodos de evaluación económica sanitaria, el método coste-utilidad emplea como utilidad, los años de vida ajustado por calidad (AVAC), que consiste, por un lado, tener en cuenta la calidad de vida ante una intervención médica, y por otro lado, los años estimados a vivir tras la intervención. Para determinar la calidad de vida, se emplea técnicas como el Juego Estándar, la Equivalencia Temporal y la Escala de Categoría. Estas técnicas nos proporcionan un valor numérico entre 0 y 1, siendo 0 el peor estado y 1 el estado perfecto de salud. Al entrevistar a un paciente a cerca de la utilidad en términos de salud, puede haber riesgo o incertidumbre en la pregunta planteada. En tal caso, se aplica el Juego Estándar con el fin de determinar el valor numérico de la utilidad o calidad de vida del paciente ante un tratamiento dado. Para obtener este valor, al paciente se le plantean dos escenarios: en primer lugar, un estado de salud con probabilidad de morir y de sobrevivir, y en segundo lugar, un estado de certeza. La utilidad se determina modificando la probabilidad de morir hasta llegar a la probabilidad que muestra la indiferencia del individuo entre el estado de riesgo y el estado de certeza. De forma similar, tenemos la equivalencia temporal, cuya aplicación resulta más fácil que el juego estándar ya que valora en un eje de ordenadas y abscisas, el valor de la salud y el tiempo a cumplir en esa situación ante un tratamiento sanitario, de forma que, se llega al valor correspondiente a la calidad de vida variando el tiempo hasta que el individuo se muestre indiferente entre las dos alternativas. En último lugar, si lo que se espera del paciente es una lista de estados de salud preferidos ante un tratamiento, empleamos la Escala de Categoría, que consiste en una línea horizontal de 10 centímetros con puntuaciones desde 0 a 100. La persona entrevistada coloca la lista de estados de salud según el orden de preferencia en la escala que después es normalizado a un intervalo entre 0 y 1. Los años de vida ajustado por calidad se obtienen multiplicando el valor de la calidad de vida por los años de vida estimados que vivirá el paciente. Sin embargo, ninguno de estas metodologías mencionadas consideran el factor edad, siendo necesario la inclusión de esta variable. Además, los pacientes pueden responder de manera subjetiva, situación en la que se requiere la opinión de un experto que determine el nivel de discapacidad del aquejado. De esta forma, se introduce el concepto de años de vida ajustado por discapacidad (AVAD) tal que el parámetro de utilidad de los AVAC será el complementario del parámetro de discapacidad de los AVAD Q^i=1-D^i. A pesar de que este último incorpora parámetros de ponderación de edad que no se contemplan en los AVAC. Además, bajo la suposición Q=1-D, podemos determinar la calidad de vida del individuo antes del tratamiento. Una vez obtenido los AVAC ganados, procedemos a la valoración monetaria de éstos. Para ello, partimos de la suposición de que la intervención sanitaria permite al individuo volver a realizar las labores que venía realizando. De modo que valoramos los salarios probables con una temporalidad igual a los AVAC ganados, teniendo en cuenta la limitación que supone la aplicación de este enfoque. Finalmente, analizamos los beneficios derivados del tratamiento (masa salarial probable) si empleamos la tabla GRF-95 (población femenina) y GRM-95 (población masculina).
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[ES] El presente trabajo es un plan de marketing para que la empresa Chocolates Valor S.A. lo implemente durante los años 2015-2016. El objetivo principal de este proyecto es aplicar los conocimientos obtenidos a lo largo de la carrera a una empresa real. Chocolates Valor es una empresa con amplia presencia en el mercado nacional y una fuerte imagen de marca. A pesar de ello, y como todas las empresas, tiene sus debilidades y no está explotando todas las oportunidades ofrecidas por el mercado. En la actualidad, la empresa cuenta con una imagen muy asociada al lujo y a un poder adquisitivo alto pero, en un entorno de crisis en el que el precio es un factor clave en la decisión de compra y los jóvenes tienen una gran importancia en el consumo, es necesario considerar la posibilidad de un cambio de posicionamiento y redireccionamiento hacia otros/ nuevos segmentos. A pesar de que Chocolates Valor diferencia dos tipos de clientes (consumidores y canal Horeca), en este trabajo solo se va a considerar el primero ya que el plan de marketing realizado está orientado exclusivamente al consumidor final.
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In the middle of the so-called pension crisis, the ageing of population and the sharp decrease in affiliations to Social Security are threatening the well-functioning of the Spanish public pension system. The purpose of this paper is to present the main challenges to be faced by the Spanish pension system, as well as to shed light on the main determinants that will condition the evolution of pension expenditure over GDP along the following decades. This quantitative analysis, which considers the 2011 and 2013 pension reforms, uses the latest data on the Spanish demographic, labor market and institutional factors in order to project the evolution of the system from the expenditure side up to 2060. For the purpose of analyzing the dynamics and the underlying drivers of pension expenditure, the so-called aggregate accounting approach will be utilized. The alternative scenarios proposed allow for exploring the robustness of the results within the baseline scenario, which constitutes the reference point of projections in the exercise. The analysis concludes that, by the end of the projected period, Spain will count on a similar public pension expenditure ratio as the current one.
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We evaluated measures of bioelectrical impedance analysis (BIA) and Fulton’s condition factor (K) as potential nonlethal indices for detecting short-term changes in nutritional condition of postsmolt Atlantic salmon (Salmo salar). Fish reared in the laboratory for 27 days were fed, fasted, or fasted and then refed. Growth rates and proximate body composition (protein, fat, water) were measured in each fish to evaluate nutritional status and condition. Growth rates of fish responded rapidly to the absence or reintroduction of food, whereas body composition (% wet weight) remained relatively stable owing to isometric growth in fed fish and little loss of body constituents in fasted fish, resulting in nonsignificant differences in body composition among feeding treatments. The utility of BIA and Fulton’s K as condition indices requires differences in body composition. In our study, BIA measures were not significantly different among the three feeding treatments, and only on the final day of sampling was K of fasted vs. fed fish significantly different. BIA measures were correlated with body composition content; however, wet weight was a better predictor of body composition on both a content and concentration (% wet weight) basis. Because fish were growing isometrically, neither BIA nor K was well correlated with growth rate. For immature fish, where growth rate, rather than energy reserves, is a more important indicator of fish condition, a nonlethal index that reflects shortterm changes in growth rate or the potential for growth would be more suitable as a condition index than either BIA measures or Fulton�
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[EUS] Azken urteetan eskolatze goiztiarrak nabarmen egin du gora gure gizartean. Gero eta gehiago dira hilabete gutxirekin haur eskolara joaten hasten diren haurrak, beraientzat segurtasun iturri den ingurunetik aldenduz. Banaketa hau bereziki zaila suerta dakieke ume gehienei aparteko ezinegonak, larritasun uneak edota gaixotasunak sortuz, eskolarekiko harremana betirako baldintzatzeaz gain. Hori dela eta, haur txikiaren eskolatzearen inguruan hausnartzeko beharra dago ezinbestean. Gaur egun haurra haur eskolako erritmo eta eskakizunetara ahalik eta azkarren moldatzeko asmoz, egokitzapen aldi bezala ezagutzen den denboraldia eskaintzen zaio haur txikiari, bere garaian Haur Hezkuntzaren bigarren ziklokoei eskaintzen hasi zitzaien bezala. Zoritxarrez honek egoerari zailtasun gehiago erantsi dizkio, ez baitira haurtxo eta haur txikiaren erritmoak errespetatzen. Hori dela eta, hezitzaileen muina eskola atsegina bihurtzeko asmotan, komunikazioan eta errespetuan oinarritutako etxekotze prozesua aurkezten da, zeinen helburua haurraren hezkuntzan parte hartzen duten guztien, familia eta eskola, elkarlanari esker bere ongizatea bermatu eta haur eskolarako igarobidea erraztuko duen giro lasaia, atsegina eta ez bakarrik adinari, baizik eta norberaren beharrizanen arabera egokia sortzea den.