418 research outputs found

    Enhancing Irrigation Efficiency but Increasing Water Use: The Jevons' Paradox

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    In this paper we analyze the conditions under which increasing technical efficiency of water use in the agricultural sector might not reduce water demand and pressures on water ecosystems. Departing from this basic problem we discuss how policy measures performed to enhance water productivity in the agriculture might be transformed into effective alternatives to improve the conservation of water resources and then guarantee the successful implementation of the Water Framework Directive. A preference revelation model is presented in the third section of the paper and one empirical application to an irrigation district in southern Spain is used in the fourth section to discuss the effectiveness of water savings measures.Water Framework Directive, Water Economics, Agricultural Economics, Simulation Models, Preference Revelation., Resource /Energy Economics and Policy,

    The MODERE Model and The Economic Analysis of Farmers’ Decisions

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    The MODERE, the Ministry of the Environment Irrigation Decision Model, is a simulation tool which uses mathematical programming methods to reveal the implicit multiattribute objective function lying behind the observed cropping decision. The model takes different criteria such as profit maximization, risk aversion, avoidance of management complexities and so forth into account. In order to determine the feasible combination of attributes of this objective function the model considers the production possibility frontier explicitly as depending on market prices, policy incentives, availability of production factors, water irrigation facilities agronomic vocation and other constraints. Once calibrated the model becomes a powerful tool to assess the impact of different policy scenarios such as subsidies decoupling, water prices modifications, irrigation technique substitution and so on. The MODERE is a preference revelation model purposedly designed to be integrated in the Decision Support Platform which is used by the Spanish Ministry of the Environment to compare the policy scenarios which are relevant to assess the effectiveness and economic impact of the measures designed to reach the environmental objectives of the Water Framework Directive. The model is supported by a comprehensive data base built on purpose for its implementation covering almost all the Spanish Irrigation Districts with high spatial detail. This model is currently one of the important modules of the information and decision support systems developed by the Economic Analysis Unit of the Water Directorate at the Ministry of the Environment in Spain.Agricultural Economics, Water Economics, Simulated Models, Land Economics/Use, Political Economy, Research Methods/ Statistical Methods, Resource /Energy Economics and Policy,

    Fractography on Rigid Ceramics with Ultra-High-Molecular- Weight Polyethylene Fabric after Ballistic Impacts

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    The impact protection systems have traditionally been developed with metallic materials and structural protection applied in the automotive sector; while personal protection systems and composite systems evolve very fast, these systems have a large increase in applications due mainly to the amplitude of the manufacturing process. In the composite system for impact protection, it exposes both functionality and the rigid systems, aimed at structural protection, and flexible systems for personal protection. Nowadays, the development of materials with ballistic applications has emphasized protection of lightweight materials, for protection against projectiles of high and low speeds, among which are the bullets from weapons, fragments of tempered steel grenade hand or aircraft fragments, or a vehicle at high speed directly against housing and human integrity. It is necessary to investigate the mechanisms of fracture of the materials usually used for protection against impact, thus, it is possible to obtain important design systems that reduce the probability of failure and protect human lives and reduce damage to infrastructure information. In this chapter, the behavior of laminate sandwich-type systems, made from handcrafted ceramic plates with sheets of polyethylene (ultra-high-molecular-weight polyethylene, UHWMPE) against the impact of a metallic projectile, has been explored. The experimental work was made of two groups with different arrangements: the first group with the side that receives the impact of ceramic material (silicon carbide, SiC)-backed polymeric material and the second group with the side that receives the impact on polymer-backed ceramic material, the plates had dimensions 200 mm2 of thickness to 5 mm for single plates and 20 mm for double plates. The experimental test was performed following the parameters of impact of NIJ III A standard. Some mechanisms (morphologies) of dissipation of kinetic energy received in the components were identified, as cited below, first in the ceramic material the formation of a crater, fracture, and delamination was observed, formed in the double and simple plates. Later, in the fabric polymeric material deformation mechanisms, such as the origination of defibrillation, conical geometry formation, delamination, twisting, and melting fibers due to the tribological contact of the metal shell impact, were observed. The exploration was culminated making a comparison between the arrangement that had higher energy absorption compared to an additional system designed with a ceramic (SiC) with less porosity, also aside to this chapter, it shows some of the deformed projectiles with a basic description of the fracture obtained after the impact, complementing the overall analysis of the systems used

    Actions to be taken for improving functional prognosis in dementia

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    The growing incidence of dementia has led to an increased need for specialized care and higher health and social costs. Functional decline is the main cause of dementia complications. Per definition, dementia diagnosis and severity stratification require a certain degree of functional impairment [1]. Therefore, it is important to determine strategies to prevent functional deterioration in both, general population and especially people with dementia. The number of older adults with some degree of disability will triple by 2050 due to the increase in the aging population and the prevalence of age-related diseases that lead to functional impairment [2]. Therefore, functional impairment and disability in old people are increasingly becoming a major public health concern. Furthermore, functional impairment severely impairs quality of life and consumes a large proportion of the public health resources, creating an important burden for health care systems. It is well known that functional loss and disability in dementia are the main consequences of cognitive decline. Therefore, most of the efforts in dementia management have been directed to stop or reverse cognitive decline. However, functional loss and disability are also the consequence of other conditions that are common in old age and comorbid with dementia, such as frailty, sarcopenia, malnutrition, falls, pulmonary or cardiovascular diseases, polypharmacy, depression, and neuropsychiatric symptoms (NPS) [3].Q3Q2The growing incidence of dementia has led to an increased need for specialized care and higher health and social costs. Functional decline is the main cause of dementia complications. Per definition, dementia diagnosis and severity stratification require a certain degree of functional impairment [1]. Therefore, it is important to determine strategies to prevent functional deterioration in both, general population and especially people with dementia. The number of older adults with some degree of disability will triple by 2050 due to the increase in the aging population and the prevalence of age-related diseases that lead to functional impairment [2]. Therefore, functional impairment and disability in old people are increasingly becoming a major public health concern. Furthermore, functional impairment severely impairs quality of life and consumes a large proportion of the public health resources, creating an important burden for health care systems. It is well known that functional loss and disability in dementia are the main consequences of cognitive decline. Therefore, most of the efforts in dementia management have been directed to stop or reverse cognitive decline. However, functional loss and disability are also the consequence of other conditions that are common in old age and comorbid with dementia, such as frailty, sarcopenia, malnutrition, falls, pulmonary or cardiovascular diseases, polypharmacy, depression, and neuropsychiatric symptoms (NPS) [3].https://orcid.org/0000-0001-5680-7880https://scholar.google.com/citations?view_op=search_authors&mauthors=carlos+alberto+cano-gutierrez&hl=es&oi=aohttps://scienti.minciencias.gov.co/cvlac/visualizador/generarCurriculoCv.do?cod_rh=0000054895&lang=esRevista Nacional - Indexad

    Structural, optical and vibrational properties of ZnO:M (M=Al3+ and Sr2+) nano and micropowders grown by hydrothermal synthesis

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    Powders of ZnO and ZnO:M (M = Al3+ and Sr2+) with 1 and 4% of M nominal content were synthetized by a hydrothermal method in a diethanolamine (DEA) medium. The samples were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), micro-Raman and photoluminescence (PL). The powder particles were spherical with average radius decreasing from 1 μm down to 70 nm with increasing Al3+ nominal content but nearly independent on the Sr2+ nominal content. The XRD and micro-Raman results indicate that both Al3+ and Sr2+ mostly incorporated substitutionally into the ZnO lattice, giving rise to compressive and tensile strain, respectively, as a result of ionic radii differences. The PL spectra for ZnO:Al exhibit a dopant-induced contribution at ∼3.1 eV, which is not observed for ZnO:Sr, due to radiative transitions involving trapping of photocarriers at theoretically expected substitutional Al3+ donor states or at Zn interstitial defects.Fil: Marín Ramírez, Oscar Alonso. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Laboratorio de Física del Sólido; ArgentinaFil: Soliz, Tania. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología; ArgentinaFil: Gutierrez, Jorge Andrés. Universidad del Quindío. Facultad de Ciencias Básicas y Tecnológicas; ColombiaFil: Tirado, Monica Cecilia. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Física. Departamento de Nanomateriales y Propiedades Dieléctricas; ArgentinaFil: Figueroa, Carlos. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Laboratorio de Física del Sólido; ArgentinaFil: Comedi, David Mario. Universidad Nacional de Tucumán. Instituto de Física del Noroeste Argentino. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Física del Noroeste Argentino; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Laboratorio de Física del Sólido; Argentin

    Death receptor 5 expression is inversely correlated with prostate cancer progression.

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    Prostate carcinoma (PCa) is one of the most common cancers in men. Prostate-specific antigen (PSA) has been widely used to predict the outcome of PCa and screening with PSA has resulted in a decline in mortality. However, PSA is not an optimal prognostic tool as its sensitivity may be too low to reduce morbidity and mortality. Consequently, there is a demand for additional robust biomarkers for prostate cancer. Death receptor 5 (DR5) has been implicated in the prognosis of several cancers and it has been previously shown that it is negatively regulated by Yin Yang 1 (YY1) in prostate cancer cell lines. The present study investigated the clinical significance of DR5 expression in a prostate cancer patient cohort and its correlation with YY1 expression. Immunohistochemical analysis of protein expression distribution was performed using tissue microarray constructs from 54 primary PCa and 39 prostatic intraepithelial neoplasia (PIN) specimens. DR5 expression was dramatically reduced as a function of higher tumor grade. By contrast, YY1 expression was elevated in PCa tumors as compared with that in PIN, and was increased with higher tumor grade. DR5 had an inverse correlation with YY1 expression. Bioinformatic analyses corroborated these data. The present findings suggested that DR5 and YY1 expression levels may serve as progression biomarkers for prostate cancer

    Sleep quality perception and romantic relationships in university students: cross-sectional study

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    Introduction: Sleep in adolescence is influenced by emotional states triggered by romantic relationships, which can be determinant in sleep quality perception.Objective: This study was designed to assess the association between sleep quality perception and romantic relationships, as well as its characteristics in late adolescent/young adult university students.Materials and methods: A cross sectional study was conducted in 443 subjects. Sleep quality perception was quantified using a validated diary for young persons. Individual attachment style, romantic relationship status and its characteristics were determined using specific validated measures.Results: Sleep quality perception was determined using five multivariate models that included statistically significant characteristics of romantic relationships. Higher sleep quality perception was associated with the level of satisfaction of a subject with the relationship and liking for the partner (p=0.035). The prevalence of romantic relationships in students was 64% (95%CI: 59.4-68.9). The individuals that were not in a romantic relationship experienced significantly prolonged sleep latency (p0.05).Conclusion: Higher sleep quality perception in university students is associated with being in a romantic relationship and the attachment style. These aspects can be identified and intervened, if support systems of educational institutions recognize their potential importance for health, wellbeing and academic performance.Introducción. El sueño en adolescentes está influenciado de manera especial por los estados emocionales presentes en las relaciones románticas. Esto puede ser determinante en la percepción de calidad del sueño.Objetivo. Evaluar la asociación entre la percepción de la calidad del sueño y las características de las relaciones románticas en estudiantes universitarios adolescentes y adultos jóvenes.Materiales y métodos. Estudio de corte transversal realizado en 443 sujetos. La percepción de calidad del sueño, los estilos de apego, estar en una relación romántica y sus características se determinaron utilizando medidas validadas.Resultados. La percepción de calidad del sueño se determinó utilizando cinco modelos multivariados que incluyeron características estadísticamente significativas de las relaciones románticas. El nivel de satisfacción del individuo con su relación de pareja y la atracción hacia esta se asoció con su nivel de percepción de calidad del sueño (p=0.035). La prevalencia de las relaciones románticas fue del 64% (IC95%: 59.4-68.9). Los que no estaban en una relación experimentaron latencia del sueño significativamente más prolongada (p0.05).Conclusión. Las relaciones sentimentales románticas y sus características se asocian con la calidad de sueño percibida por los individuos. Estos aspectos pueden ser identificados e intervenidos y ser útiles para los sistemas de apoyo de las instituciones educativas

    Comparison of different methods of grapevine yield Prediction in the time window Between fruitset and veraison

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    Aim: To compare grape yield prediction methods to determine which provide the best results in terms of earliness of prediction in the growing season, accuracy and precision. Methods and results: The grape yields predicted by six models ? one for use at fruitset (FS), two for use at veraison (V1 and V2), and three for use during the lag phase (LP40, LP50 and LP60) ? were compared to fieldmeasured yields. Regressions for the yield predicted by each model were constructed. The V1 and V2 models had the highest R2 (0.75) and efficiency index (EF; 0.67-0.71) and the lowest RMSE values (±16-17%, or <0.5 kg per mof row). The FS model had the same or similar R2 (0.58), EF (0.06) and RMSE (±30%, or <0.83 kg per m of row) values as the LP models, but allowed yield predictions to be made one month earlier
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