435 research outputs found

    Air conditioning in the region of Madrid, Spain: an approach to electricity consumption, economics and CO₂emissions

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    An understanding of electricity consumption due to residential air conditioning (AC) may improve production and environmental impact strategy design. This article reports on a study of peak and seasonal electricity consumption for residential air conditioning in the region of Madrid, Spain. Consumption was assessed by simulating the operation of AC units at the outdoor summer temperature characteristics of central Spain. AC unit performance when operating under part load conditions in keeping with weather conditions was also studied to find cooling demand and energy efficiency. Like wise final electricity consumption was computed and used to calculate energy costs and greenhouse gas emissions (GHGs). Cooling demand, when family holidays outside the region were factored into the calculations, came to 1.46x10⁹ kWh. Associated seasonal electricity demand was 617x10⁶ kWh and seasonal performance of AC units around 2.4. Electricity consumption in the whole region was observed to peak on 30 June 2008 at 5.44x10⁶ kW, being the load attributable to residential AC 1.79x10⁶ kW, resulting about 33% of the total peak consumption. The seasonal cost per household was about €156 and the total equivalent warming impact was 572x10³t CO₂. The method proposed can be adapted for use in other regionsThis study was funded by the Spanish Ministry of Science and Innovation under Projects INVISO, sub-project SP3 “Sustainable power generation in housing” and ENE2010-20650-C02-01. Author A. Gonzalez-Gil is grateful to the Spanish National Research Council (CSIC) for its support while he worked toward his PhD. The authors also wish to thank J. Cabetas from Iberdrola de Distribución Eléctrica S.A.U. for the information furnishedPublicad

    Making sense of the bizarre behaviour of horizons in the McVittie spacetime

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    The bizarre behaviour of the apparent (black hole and cosmological) horizons of the McVittie spacetime is discussed using, as an analogy, the Schwarzschild-de Sitter-Kottler spacetime (which is a special case of McVittie anyway). For a dust-dominated "background" universe, a black hole cannot exist at early times because its (apparent) horizon would be larger than the cosmological(apparent) horizon. A phantom-dominated "background" universe causes this situation, and the horizon behaviour, to be time-reversed.Comment: 8 pages, 3 figure

    Actions for the Restoration of the Biodiversity of Forest Ecosystems in Cuba

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    The Earth is threatened daily by the degradation of its ecosystems due to fragmentation. One of the main consequences is biodiversity loss. Despite the economic progress and conservation actions carried out in many countries, the planet is losing genuine tropical forest due to diverse reasons. This chapter presents the results obtained during the restoration of three tropical forests in Cuba: 1) the mesophyll semi-deciduous forest in the western sector of the Biosphere Reserve 'Sierra del Rosario' (BRSR); 2) the riverside forest of the Cuyaguateje River in western Cuba; and 3) the exploited native rainforests of the sector Quibiján-Naranjal of the River Toa in eastern Cuba

    Resolución de problemas científicos escolares y promoción de competencias de pensamiento científico. ¿Qué piensan los docentes de química en ejercicio?

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    En el artículo se exponen los resultados de una investigación realizada en el marco del proyecto FONDECYT 1070795, cuyo objetivo consistió en identificar y caracterizar las nociones que tienen los profesores de nivel medio respecto a las competencias de pensamiento científico y solución de problemas, y la manera en que ambos deben trabajarse en la enseñanza de la química. Con el empleo de una muestra intencional de 33 profesores, seleccionados de un total de 117 que se incorporaron a otras fases de la investigación y mediante la administración de un cuestionario especialmente diseñado, se logró poner de manifiesto que en ellos predomina una imagen fragmentada y a veces contradictoria de la solución de problemas y de las competencias de pensamiento científico; dicha representación incorpora aspectos de inestimable valor para la formación del estudiante competente, a la vez que incluye otros que en manera alguna favorecen dicha formación en correspondencia con las exigencias actuales. Es notable que competencias de pensamiento científico y solución de problemas no se constituyan como sistema totalmente coherente en la conceptualización de los profesores investigados. Como dato relevante, se constató la oscilante valoración del carácter subjetivo de las situaciones problémicas y los problemas; junto al papel importante que, en opinión de gran parte de los profesores, desempeña el lenguaje, se le otorga un valor oscilante al trabajo con la teoría por parte de los estudiantes; igualmente resulta difusa, y a veces contradictoria, su aproximación a los procesos de algoritmización.In the article the results of an investigation conducted within the framework of the project FONDECYT 1070795 are exposed. The aims of the research were to identify and characterize the representations and knowledge that teachers in service have, from an average level of education, with respect to the competences of scientific thought and problem solution, and the way in which both should be approached. With the use of an intentional sample of 133, teachers selected from a total of 117 who were incorporated to other phases of the research trough the administration of a questionnaire especially designed, was show the predominance of a very fragmented image, sometimes contradictory, about the solution of problems and about relation between competences of scientific thought; this representation incorporates aspects of great value for the formation of the competent students, and at the same time it includes other aspects that in no way favor this formation, according to the present assessments. It is remarkable that both competences for scientific thought and solution of problems are not constituted as a totality and coherent system in the thinking of the teachers who participated in the research. It should be pointed out that we found data that show an oscillating valuation of the subjective character of the problematic situations and the problem itself; these data show, as well, that teachers give a very important role to language. It is stated that teachers give an oscillating value to the fact that students must deal with theories. It should be noted too that their approaches to the algorithmic processes are very vague, and sometimes contradictory

    Prevalence of Multi-Resistant Microorganisms and Antibiotic Stewardship among Hospitalized Patients Living in Residential Care Homes in Spain: A Cross-Sectional Study

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    Antimicrobial resistance is a growing global health problem. Patients living in care homes are a vulnerable high-risk population colonized by multidrug-resistant organisms (MDRO). We identified a case series of 116 residents of care homes from a cohort of 540 consecutive patients admitted to the internal medicine service of our hospital. We performed early diagnostic tests of MDRO through anal exudates in our sample. The prevalence of MDRO colonization was 34.5% of residents and 70% of them had not been previously identified in the clinical records. Previous hospitalizations and in-hospital antibiotic administration were significantly associated with the presence of MDRO. Our results emphasize the need to consider care homes in the planning of regional and national infection control measures and for implementing surveillance systems that monitor the spread of antimicrobial resistance in Spain. Systematic early testing upon admission to hospital services with a high prevalence of patients with MDRO colonization (e.g., internal medicine) could contribute to the adoption of adequate prevention measures. Specific educational programs for care home staff should also be implemented to address this increasing problem.Catedra de Docencia e Investigacion SEMERGEN-Medicina de Familia, University of Granada, Spai

    Mitochondrial dysfunction and mitophagy activation in blood mononuclear cells of fibromyalgia patients: implications in the pathogenesis of the disease

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    This is an open access article distributed under the terms of the Creative Commons Attribution License.[Introduction]: Fibromyalgia is a chronic pain syndrome with unknown etiology. Recent studies have shown some evidence demonstrating that oxidative stress may have a role in the pathophysiology of fibromyalgia. However, it is still not clear whether oxidative stress is the cause or the effect of the abnormalities documented in fibromyalgia. Furthermore, the role of mitochondria in the redox imbalance reported in fibromyalgia also is controversial. We undertook this study to investigate the role of mitochondrial dysfunction, oxidative stress, and mitophagy in fibromyalgia. [Methods]: We studied 20 patients (2 male, 18 female patients) from the database of the Sevillian Fibromyalgia Association and 10 healthy controls. We evaluated mitochondrial function in blood mononuclear cells from fibromyalgia patients measuring, coenzyme Q10 levels with high-performance liquid chromatography (HPLC), and mitochondrial membrane potential with flow cytometry. Oxidative stress was determined by measuring mitochondrial superoxide production with MitoSOX™ and lipid peroxidation in blood mononuclear cells and plasma from fibromyalgia patients. Autophagy activation was evaluated by quantifying the fluorescence intensity of LysoTracker™ Red staining of blood mononuclear cells. Mitophagy was confirmed by measuring citrate synthase activity and electron microscopy examination of blood mononuclear cells. [Results]: We found reduced levels of coenzyme Q10, decreased mitochondrial membrane potential, increased levels of mitochondrial superoxide in blood mononuclear cells, and increased levels of lipid peroxidation in both blood mononuclear cells and plasma from fibromyalgia patients. Mitochondrial dysfunction was also associated with increased expression of autophagic genes and the elimination of dysfunctional mitochondria with mitophagy. [Conclusions]: These findings may support the role of oxidative stress and mitophagy in the pathophysiology of fibromyalgia.This work was supported by grants FIS PI080500 and FIS EC08/00076, Ministerio de Sanidad, Spain. The authors dedicate this manuscript to FM patients and AFIBROSE (Asociación de Fibromialgia de Sevilla) for their unconditional help.Peer Reviewe

    A comparison of feature extractors for panorama stitching in an autonomous car architecture.

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    Panorama stitching consists on frames being put together to create a 360o view. This technique is proposed for its implementation in autonomous vehicles instead of the use of an external 360o camera, mostly due to its reduced cost and improved aerodynamics. This strategy requires a fast and robust set of features to be extracted from the images obtained by the cameras located around the inside of the car, in order to effectively compute the panoramic view in real time and avoid hazards on the road. In this paper, we compare and discuss three feature extraction methods (i.e. SIFT, BRISK and SURF) for image feature extraction, in order to decide which one is more suitable for a panorama stitching application in an autonomous car architecture. Experimental validation shows that SURF exhibits an improved performance under a variety of image transformations, and thus appears to be the most suitable of these three methods, given its accuracy when comparing features between both images, while maintaining a low time consumption. Furthermore, a comparison of the results obtained with respect to similar work allows to increase the reliability of our methodology and the reach of our conclusions

    Variable expression of cerebral cavernous malformations in carriers of a premature termination codon in exon 17 of the Krit1 gene

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    BACKGROUND: Cerebral cavernous malformations (CCM) present as either sporadic or autosomal dominant conditions with incomplete penetrance of symptoms. Differences in genetic and environmental factors might be minimized among first-degree relatives. We therefore studied clinical expression in a family with several affected members. METHODS: We studied a three-generation family with the onset of CCM as a cerebral haemorrhage in the younger (four-year-old) sibling. Identification and enumeration of CCMs were performed in T2-weighted or gradient-echo MRIs of the whole brains. Genetic analysis comprised SCCP, sequencing and restriction polymorphism of the Krit1 gene in the proband and at risk relatives. RESULTS: The phenotypes of cerebral cavernous malformations (CCMs) in carriers of Krit1 mutations were very variable. We identified a novel frameshift mutation caused by a 1902A insertion in exon 17 of the Krit1 gene, which leads to a premature TAA triplet and predicts the truncating phenotype Y634X. A very striking finding was the absence of both clinical symptoms and CCMs in the eldest sibling harbouring the 1902insA. CONCLUSIONS: Patients in this family, harbouring the same mutation, illustrate the very variable clinical and radiological expression of a Krit1 mutation. The early and critical onset in the proband contrasts with minor clinical findings in affected relatives. This consideration is important in genetic counselling
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