736 resultados para Caña de azúcar


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Distribución del cultivo de caña por distrito en el cantón de Poás para el año 1986.

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Proyecto de Actualización Cartográfica de usos de la Tierra a escala 1:10.000 GAM de Costa Rica. Elaboración de Cartografía digital y Ortofotos.

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Mapa de ubicación de amenazas naturales, con el objetivo de apoyar el proceso de prevención contra desastres naturales en el nivel local.

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Background Alcoholism imposes a tremendous social and economic burden. There are relatively few pharmacological treatments for alcoholism, with only moderate efficacy, and there is considerable interest in identifying additional therapeutic options. Alcohol exposure alters SK-type potassium channel (SK) function in limbic brain regions. Thus, positive SK modulators such as chlorzoxazone (CZX), a US Food and Drug Administration–approved centrally acting myorelaxant, might enhance SK function and decrease neuronal activity, resulting in reduced alcohol intake. Methods We examined whether CZX reduced alcohol consumption under two-bottle choice (20% alcohol and water) in rats with intermittent access to alcohol (IAA) or continuous access to alcohol (CAA). In addition, we used ex vivo electrophysiology to determine whether SK inhibition and activation can alter firing of nucleus accumbens (NAcb) core medium spiny neurons. Results Chlorzoxazone significantly and dose-dependently decreased alcohol but not water intake in IAA rats, with no effects in CAA rats. Chlorzoxazone also reduced alcohol preference in IAA but not CAA rats and reduced the tendency for rapid initial alcohol consumption in IAA rats. Chlorzoxazone reduction of IAA drinking was not explained by locomotor effects. Finally, NAcb core neurons ex vivo showed enhanced firing, reduced SK regulation of firing, and greater CZX inhibition of firing in IAA versus CAA rats. Conclusions The potent CZX-induced reduction of excessive IAA alcohol intake, with no effect on the more moderate intake in CAA rats, might reflect the greater CZX reduction in IAA NAcb core firing observed ex vivo. Thus, CZX could represent a novel and immediately accessible pharmacotherapeutic intervention for human alcoholism. Key Words: Alcohol intake; intermittent; neuro-adaptation; nucleus accumbens; SK potassium channel

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Emergency Health Services (EHS), encompassing hospital-based Emergency Departments (ED) and pre-hospital ambulance services, are a significant and high profile component of Australia’s health care system and congestion of these, evidenced by physical overcrowding and prolonged waiting times, is causing considerable community and professional concern. This concern relates not only to Australia’s capacity to manage daily health emergencies but also the ability to respond to major incidents and disasters. EHS congestion is a result of the combined effects of increased demand for emergency care, increased complexity of acute health care, and blocked access to ongoing care (e.g. inpatient beds). Despite this conceptual understanding there is a lack of robust evidence to explain the factors driving increased demand, or how demand contributes to congestion, and therefore public policy responses have relied upon limited or unsound information. The Emergency Health Services Queensland (EHSQ) research program proposes to determine the factors influencing the growing demand for emergency health care and to establish options for alternative service provision that may safely meet patient’s needs. The EHSQ study is funded by the Australian Research Council (ARC) through its Linkage Program and is supported financially by the Queensland Ambulance Service (QAS). This monograph is part of a suite of publications based on the research findings that examines the existing literature, and current operational context. Literature was sourced using standard search approaches and a range of databases as well as a selection of articles cited in the reviewed literature. Public sources including the Australian Institute of Health and Welfare (AIHW), the Council of Ambulance Authorities (CAA) Annual Reports, Australian Bureau of Statistics (ABS) and Department of Health and Ageing (DoHA) were examined for trend data across Australia.

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The degradation efficiencies and behaviors of caffeic acid (CaA), p-coumaric acid (pCoA) and ferulic acid (FeA) in aqueous sucrose solutions containing the mixture of these hydroxycinnamic acids (HCAs) mixtures were studied by the Fenton oxidation process. Central composite design and multi-response surface methodology were used to evaluate and optimize the interactive effects of process parameters. Four quadratic polynomial models were developed for the degradation of each individual acid in the mixture and the total HCAs degraded. Sucrose was the most influential parameter that significantly affected the total amount of HCA degraded. Under the conditions studied there was < 0.01% loss of sucrose in all reactions. The optimal values of the process parameters for a 200 mg/L HCA mixture in water (pH 4.73, 25.15 °C) and sucrose solution (13 mass%, pH 5.39, 35.98 °C) were 77% and 57% respectively. Regression analysis showed goodness of fit between the experimental results and the predicted values. The degradation behavior of CaA differed from those of pCoA and FeA, where further CaA degradation is observed at increasing sucrose and decreasing solution pH. The differences (established using UV/Vis and ATR-FTIR spectroscopy) were because, unlike the other acids, CaA formed a complex with Fe(III) or with Fe(III) hydrogen-bonded to sucrose, and coprecipitated with lepidocrocite, an iron oxyhydroxide.

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The experience of lesbian, gay, bisexual, transgender, intersex and queer (LGBTIQ) health consumers has, in the last decade, gained attention and is now recognised as one of the social determinants of health. Our recent meta-synthesis on the experiences of LGBTIQ health and medical professionals demonstrated that they are susceptible to higher levels of anxiety and depression partially due to lack of acceptance in their workplace. The paramedic workforce is known to be a high risk occupational group for post-traumatic stress disorder and depression. Theoretically, LGBTIQ paramedics working in a heteronormative culture may experience increased level of discrimination and stress than their heterosexual colleagues. The integration of LGBTIQ into the paramedic workforce is unfeatured in our systematic review. While LGBTIQ health professionals receive legislative protection against discrimination, discrimination still exists in practice through lack of visibility. There is a common misconception that LGBTIQ is a homogenous group with equal needs. Effective and efficient integration of LGBTIQ health professionals could improve workplace satisfaction, workforce retention, and equity of access by marginalised groups.

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Along with the increased life span of individuals, the burden of old age-associated diseases has inevitably increased. Alzheimer s disease (AD), probably the most well known geriatric disease, belongs to the old age-associated amyloid diseases. The purpose of this study was to investigate the frequency, genetic and health-associated risk factors, mutual association, and amyloid proteins in two old age-associated amyloid disorders senile systemic amyloidosis (SSA) and cerebral amyloid angiopathy (CAA) as part of the prospective population-based Vantaa 85+ autopsy study on a Finnish population aged 85 years or more (Studies I-III), completed with a case report on a patient with advanced AGel amyloidosis (Study IV). The numbers of patients investigated in the studies (I-III) were 256, 74, and 63, respectively. The diagnosis and grading of amyloid were based upon histological examination of tissue samples obtained post mortem and stained with Congo red. The amyloid fibril and associated proteins were characterized by immunohistochemical staining methods. The genotype frequencies of 20 polymorphisms in 9 genes and information on health-associated risk factors in subjects with and without SSA and CAA were compared. In a Finnish population ≥ 95 years of age, SSA and CAA occurred in 36% and 49% of the subjects, respectively. In total, two-thirds of these very elderly individuals had SSA, CAA, or both. However, in only 14% of the population these two conditions co-occurred. In subjects 85 years or older, the prevalence of SSA was 25%. In this population, SSA was associated with age at the time of death (p=0.002), myocardial infarctions (MIs; p=0.004), the G/G (Val/Val) genotype of the exon 24 polymorphism in the alpha2-macroglobulin (α2M) gene (p=0.042) and with the H2 haplotype of the tau gene (p=0.016). In contrast, the presence of CAA was strongly associated with APOE e4 (p=0.0003), with histopathological AD (p=0.0005), and with clinical dementia (p=0.01) in both e4+ (p=0.02) and e4- (p=0.06) individuals. Apart from demonstrating the amyloid fibril proteins, complement proteins 3d (C3d) and 9 (C9) were detected in the amyloid deposits of CAA and AGel amyloidosis, and α2M protein was found in fibrous scar tissue close to SSA. In conclusion, this first population based study on SSA shows that both SSA and CAA are common in very elderly individuals. Old age, MIs, the exon 24 polymorphism of the α2M gene, and H1/H2 polymorphism of the tau gene associate with SSA while clinical dementia and APOE ε4 genotype associate with CAA. The high prevalence of CAA, combined with its association with clinical dementia independent of APOE genotype, neuropathological AD, or SSA, also highlights its clinical significance in the very aged, among which the serious end stage complications of CAA, namely multiple infarctions and hemorrhages, are rare. The report on a patient having advanced AGel amyloidosis added knowledge on the disease and showed that this generally benign condition occasionally may lead to death. Further studies are warranted to confirm the findings in other populations. Also, the role of α2M and tau in the pathogenesis of SSA and the involvement of complement in the process of amyloid beta (Aβ) protein elimination from the brain remain to be clarified. Finally, the high prevalence of SSA in the elderly raises the need for prospective clinical studies to define its clinical significance.

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A new class of bio-composite polymer electrolyte membranes comprising chitosan (CS) and certain biomolecules in particular, plant hormones such as 3-indole acetic acid (IAA), 4-chlorophenoxy acetic acid (CAA) and 1-naphthalene acetic acid (NAA) are explored to realize proton-conducting bio-composite membranes for application in direct methanol fuel cells (DMFCs). The sorption capability, proton conductivity and ion-exchange capacity of the membranes are characterized in conjunction with their thermal and mechanical behaviour. A novel approach to measure the permeability of the membranes to both water and methanol is also reported, employing NMR imaging and volume localized NMR spectroscopy, using a two compartment permeability cell. A DMFC using CS-IAA composite membrane, operating with 2M aqueous methanol and air at 70 degrees C delivers a peak power density of 25 mW/cm(2) at a load current density of 150 mA/cm(2). The study opens up the use of bio-compatible membranes in polymer-electrolyte-membrane fuel cells. (C) 2011 The Electrochemical Society. [DOI: 10.1149/2.030111jes] All rights reserved.

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Computer Assisted Assessment (CAA) has been existing for several years now. While some forms of CAA do not require sophisticated text understanding (e.g., multiple choice questions), there are also student answers that consist of free text and require analysis of text in the answer. Research towards the latter till date has concentrated on two main sub-tasks: (i) grading of essays, which is done mainly by checking the style, correctness of grammar, and coherence of the essay and (ii) assessment of short free-text answers. In this paper, we present a structured view of relevant research in automated assessment techniques for short free-text answers. We review papers spanning the last 15 years of research with emphasis on recent papers. Our main objectives are two folds. First we present the survey in a structured way by segregating information on dataset, problem formulation, techniques, and evaluation measures. Second we present a discussion on some of the potential future directions in this domain which we hope would be helpful for researchers.

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La preocupante situación por el uso excesivo de productos químicos en granos almacenados, ha llevado a la búsqueda de métodos efectivos no químicos para prevenir las pérdidas ocasionadas por los insectos. Entre estos métodos tenemos el uso de atmósferas modificadas (AM) el cual ha sido utilizado en otros países con buenos resultados. Este método consiste en la descomposición o fermentación de materiales vegetales como substrato para la generación de CO2 (dióxido de carbono) en un biogenerador, conectado a silos metálicos u otros depósitos de granos herméticos donde el gas es transferido pasivamente al depósito de granos. Nos propusimos identificar fuentes naturales para la producción de CO2 y determinar la eficacia del método de atmósferas controladas en el control del Sitophilus zeamais Motsch. Para el estudio se realizaron dos etapas: Identificación de fuentes naturales para la producción de CO2 a partir del proceso de fermentación, donde se probaron caiia de azúcar, banano y maíz, utilizando para cada material tratamientos con y sin levadura comercial en concentración de 0.5% y 0% respectivamente de la cantidad total del material a fermentar en el biodigestor. Se determinó el momento inicial, máximo y final de la producción de CO2 . El tipo de biogenerador utilizado para todos los ensayos consistió de un depósito plástico de 18 l. de capacidad, donde se colocaron los materiales a fermentar. Se utilizó un indicador de agua. La variable a medir fue la emisión de burbujas en un período de tres minutos a intervalos de dos horas. Se determinó el porcentaje de mortalidad del S. zeamaiz en silos metálicos de 4qq. con maíz utilizando la AM. El silo metálico fue llenado con maiz hasta las 5/6 partes de su capacidad total; las jaulas que se utiüzaron fueron recipientes plásticos de 1L de capacidad con maíz-grano y 100 gorgojos del maíz adultos en su interior, colocadas a tres diferentes profundidades dentro del silo metálico. El porcentaje de C02 contenido en el silo metálico se midió con el método bioquímico del Hidróxido de Sodio (NaOH). El índice de mortalidad se evaluó a los 6, 8 y 10 días. Los mejores resultados en producción de gas se obtuvieron con el banano, con un rendimiento promedio de 91.9 y 52.6 burbujas por tres minutos a intervalos de dos horas en un período de 40 horas. Con un porcentaje mayor al 25% de CO 2 en el interior del silo metálico (atmósfera interna) y más de 6 días de exposición se obtuvo la mortalidad del gorgojo del maíz superior al 95%; concluyendo que la mortalidad del gorgojo del maíz estará en dependencia del porcentaje de CO2 en el interior del silo metálico.

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Resumen: Los hallazgos de instrumentos musicales en entierros y cuevas de Santanderhan permitido reconstruir algunas de las características del arte musical Guane. El grupo de artefactos estudiado esta compuesto porocho quenas de caña, una quena de hueso, una ocarina de cerámica, una ocarina de caña, una zampoña de hueso y unas maracas; estos instrumentos son la única evidenciaen existencia de la práctica musical Guane más allá de los escritos realizados por los cronistas españoles, por lo que han sido estudiados y consignados aún cuando algunos presentan un avanzado estado de deterioro. El estudio acústico y la observación realizada con la aprobación de las instituciones en las cuales reposan estos artefactos han permitido obtenerinformación acerca de la organología, las técnicas de construcción y organización modal de los instrumentos, con lo cual se diluyen las nociones de una cultura musical caótica para dar paso al encuentro de los sistemas sonoros específicos utilizados por esta comunidad prehispánica.

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Resumen: El intercambio de culturas con ocasión de la residencia de los nuevos pobladores en tierras americanas, trajo como consecuencia la implantación de diferentes normativas provenientes de la Hispania medieval, pero también un grave desajuste en la aplicación de dichas costumbres para las mujeres, según fuera su estatus social. En ocasiones, indígenas, mestizas y españolas lograron alcanzar posturas flexibles –de parte de las autoridades canónicas y civiles– a la hora de ser multadas o castigadas por la ley; otras veces, su peso caía con todo el rigor sin atender a ningún tipo de diferenciación entre las mujeres.