147 research outputs found

    Cálculo de índices de confort térmico en recintos cerrados con transferencia de calor

    Get PDF
    El trabajo que se presenta forma parte de los estudios que el grupo de investigación "Análisis Térmico y Ventilación en la Ingeniería y la Edificación" está desarrollando para la realización del Proyecto "Estudio de la eficiencia energética y del confort en un edificio bioclimático" en la Universidad Politécnica de Madrid. El objetivo general de dicho proyecto es aportar, a través de modelos físicos y datos experimentales, información relevante que sirva para optimizar el consumo energético de una vivienda bioclimática en la Comunidad de Madrid. Con este fin, en el presente trabajo se simula el comportamiento del aire en una habitación, mediante un modelo CFD (Computational Fluid Dynamics), con el fin de determinar los índices deconfort térmico en el recinto, bajo dos supuestos de calefacción utilizados en edificación: radiadores y suelo radiante

    Vue d'ensemble

    Get PDF
    Artelogie publie son dixième numéro avec une série de nouveautés éditoriales dont nous avons la satisfaction de les partager avec nos lecteurs. À partir de ce numéro, la revue intègrera la plateforme de périodiques indexés dans le domaine des sciences humaines et sociales françaises - Revues.org, qui inclut le portail OpenEdition. Outre ces potentialités, il faut signaler qu’avec ce dixième numéro d'Artelogie débute une nouvelle collaboration avec la revue Critique d’Art - publication issue d..

    Isotopic hydrology, nuclear tool for sustainable management of water resources

    Get PDF
    La gestión y protección del agua subterránea, establece una utilización planificada del acuífero, sin causar daños en calidad y cantidad; considerando los factores sociales y económicos del entorno. Se caracterizó mediante el uso de las técnicas nucleares (hidrología isotópica), el acuífero kárstico de la sub-cuenca Artemisa-Quivicán, el cual sustenta la producción alimenticia de la provincia Artemisa y la Habana. Para ello se desarrollaron 3 etapas investigativas: el diseño y definición de la red optimizada para el monitoreo isotópico y fisicoquímico en el agua subterránea y superficial; la caracterización isotópica (tritio, oxígeno disuelto, deuterio) y físicoquímica (macro-componentes químicos, parámetros físicos y de calidad) del agua de la subcuenca y de las precipitaciones registradas en la región y la identificación de las posibles fuentes de contaminación en la sub-cuenca.Management and protection of the ground water requires a planned use of the aquifer, considering the social and economic factors of the environment without causing damages in quality and quantity. The karstic aquifer of the sub-basin Artemisa-Quivicán, which supports food production for Artemisa and Havana counties, has been characterised through the nuclear techniques application (isotopic hydrology). Three investigation stages were developed: the design and definition of the optimized network for the isotopic and physicochemical monitoring of ground and surface waters; the isotopic characterization (tritium, dissolved oxygen, deuterium) and physicochemical characterization (chemical macro-components, physical and quality parameters) of the sub-basin water and of registered precipitations in the region; and finally the identification of the possible contamination sources in the sub-basin.Fil: Peralta Vital, José Luis. Centro de Protección e Higiene de las Radiaciones; CubaFil: Gil Castillo, Reinaldo. Centro de Protección e Higiene de las Radiaciones; CubaFil: Dapeña, Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geocronología y Geología Isotopica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geocronología y Geología Isotopica; ArgentinaFil: Valdés González, Lourdes. Empresa de Investigación, Proyectos e Ingeniería La Habana; CubaFil: Olivera Acosta, Jorge. Instituto de Geofísica y Astronomía; CubaFil: Morejón Miranda, Yilian Maria. Dirección Provincial de Suelos y Fertilizantes; Cub

    Telemedicine, Psychology and Diabetes: Evaluation of results and cost analysis

    Get PDF
    The Psychosocial Aspects of Diabetes (PSAD) Study Group is an official Study Group of the European Association for the Study of Diabetes (EASD).AIMS: Evidences of benefits of telemedicine in T1DM patients on continuous subcutaneous insulin infusion (CSII) treatment are limited. Aims: 1) to analyse the differences in clinical and psychological variables between subjects with T1DM on CSII treatment who were included in a Telecare (TC) program, and subjects with T1DM on CSII treatment who received Conventional care (CC); 2) Perform a cost analysis of the use of telemedicine in DM1 patients treated with CSII (TC versus CC). METHODS and PARTICIPANTS: Cross-over randomized clinical trial with duration of 18 months. 51 patients signed informed consent. Participants were randomly assigned to receive TC program or CC during 6 months, and after a 3 months wash-out period, patients changed to CC or to TC respectively. TC program included monthly visits using an Internet platform. CC comprised face-to-face visits every three months. Sociodemographic, clinical and psychological data was measured at the beginning and at the end of TC and CC. The direct and indirect costs were also measured. T Student was performed to assess differences between first and last visits in both groups (TC / CC). RESULTS: Patients with telemedicine at the end of treatment, have fewer hyperglycemia / week, less distress and greater adherence. Considering both direct and indirect costs, the cost per treatment (TC / CC) is similar. CONCLUSIONS: Telemedicine has significant implications for clinical and psychological variables and has the same cost (total) than the conventional treatment. Therefore, it can be a useful alternative for treatment of DM1 patients with CSII. However, studies with a larger sample size are needed.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Interleukin 27 could be useful in the diagnosis of tuberculous pleural effusions

    Get PDF
    BACKGROUND: The diagnosis of tuberculous pleural effusion (TBPE) has some limitations. We studied the efficacy of interleukin-27 (IL-27) in the diagnosis of TBPE. METHODS: We measured IL-27, adenosine deaminase (ADA), ADA-2, interferon-gamma (IFNgamma), and the ADA.IL-27 and ADA-2.IL-27 products in all the pleural effusion fluids. The diagnostic yield of IL-27 was evaluated with receiver operating characteristic curves. RESULTS: Of 431 pleural effusions, 70 were tuberculous, 146 were neoplastic, 58 were parapneumonic, 28 were empyemas, 88 were transudates, and 41 were other types. With a cutoff point of 0.55 ng/mL, IL-27 had a sensitivity of 91.4% and a specificity of 85.1%, which were significantly less than ADA, ADA-2, IFNgamma, ADA.IL-27, or ADA-2.IL-27. The area under the receiver operating characteristic curve for IL-27 (0.963) was also significantly lower than that for the other markers, except for IFNgamma. However, IL-27 improved the sensitivity of ADA and ADA-2 through ADA.IL-27 and ADA-2.IL-27 products (100% for both). CONCLUSIONS: IL-27 is less efficient than ADA and ADA-2 in the diagnosis of TBPE. However, ADA.IL-27 and ADA-2.IL-27 improve the diagnostic sensitivity of ADA and ADA-2, and thus could be useful in situations of high clinical suspicion and low ADA level. A value above the cutoff point of the latter is practically diagnostic of TBPE

    First-mile logistics parcel pickup: Vehicle routing with packing constraints under disruption

    Full text link
    peer reviewedFirst-mile logistics tackles the movement of products from retailers to a warehouse or distribution centre. This first step towards the end customer has been pushed by large e-commerce platforms forming extensive networks of partners and is critical for fast deliveries. First-mile pickup requires efficient methods different from those developed for last-mile delivery, among other reasons due to the complexity of cargo features and volume — increasing the relevance of advanced packing methods. More importantly, the problem is essentially dynamic and the pickup process, in which the vehicle is initially empty, is much more flexible to react to disruptions arising when the vehicles are en route. We model the static first-mile pickup problem as a vehicle routing problem for a heterogeneous fleet, with time windows and three-dimensional packing constraints. Moreover, we propose an approach to tackle the dynamic problem, in which the routes can be modified to accommodate disruptions — new customers’ demands and modified requests of known customers that are arriving while the initially established routes are being covered. We propose three reactive strategies for addressing the disruptions depending on the number of vehicles available, and study their results on a newly generated benchmark for dynamic problems. The results allow quantifying the impact of disruptions depending on the strategy used and can help the logistics companies to define their own strategy, considering the characteristics of their customers and products and the available fleet

    Endoscopic Intragastric Injection of Botulinum Toxin A in Obese Patients Accelerates Weight Loss after Bariatric Surgery: Follow-Up of a Randomised Controlled Trial (IntraTox Study)

    Get PDF
    Intragastric injection of botulinum toxin A (BT-A) has been shown to be effective for weight loss up to six months after administration, according to previous studies. Our objective was to determine, in patients on bariatric surgery waiting lists, the effect of BT-A on weight loss in the pre- and postoperative period and to analyse if there are different responses based on Body Mass Index (BMI). Methods: We performed a follow-up analysis of the IntraTox study, which included 46 patients on bariatric surgery waiting lists in a single-centre, randomised, double-blind, placebo-controlled clinical trial. The treatment group received intragastric BT-A, whereas the control group received physiological saline solution. The one-time procedure was performed at the time of diagnostic endoscopy 7–8 months before surgery. Weight loss was evaluated at admission and after 4 and 12 weeks from the bariatric surgery. Our analysis was stratified by BMI at randomisation. Results: weight loss percentage on the day of surgery, with respect to the initial visit, was −4.5 ± 3.9% for the control group vs. −7.6 ± 4.2%, for the treatment group (p = 0.013). Weight loss percentage tended to remain greater in the treatment group one month after the intervention (−12.7 ± 4.7% vs. −15.2 ± 4.6%, p = 0.07) and become similar three months after (−21.6 ± 4.7% vs. −21.6 ± 4.6%). After stratifying by BMI, only patients with BMI over 50 kg/m2 allocated to the treatment group obtained a greater weight loss at the end of the trial, the day of surgery, and one month after, compared with the placebo group (−4.9 ± 4.9%, −10.8 ± 5.3% and −17.1 ± 3.8% vs. −0.1 ± 2.6%, −4.3 ± 3.2% and −12.8 ± 4.1%, respectively (p < 0.05). Conclusions: intragastric injection of BT-A is effective to achieve significant weight loss, especially in extreme obesity. Its use before bariatric surgery enhances perioperative weight loss.Merz Pharma (Frankfurt am Main, Germany) collaborated with a non-restricted grant. The study was co-funded by the Sociedad Andaluza de Endocrinología, Diabetes y Nutrición (SAEDYN) and the Sociedad Andaluza de Nutrición, Clínica y Dietética (SANCYD). This research was supported by the Plataforma Española de Investigación Clínica y Ensayos Clínicos, SCReN (Spanish Clinical Research Network), funded by ISCIII-Subdirección General de Evaluación y Fomento de la Investigación, through the projects PT13/0002/0020 and PT17/0020, integrated in the Plan Estatal de I+D+I 2013-2016 and co-funded by the European Regional Development Fund (ERDF). Partial funding for open access charge: Universidad de Málag

    Influence of threshold selection and image sequence in in-vivo segmentation of enlarged perivascular spaces

    Get PDF
    BACKGROUND: Growing interest surrounds perivascular spaces (PVS) as a clinical biomarker of brain dysfunction given their association with cerebrovascular risk factors and disease. Neuroimaging techniques allowing quick and reliable quantification are being developed, but, in practice, they require optimisation as their limits of validity are usually unspecified.NEW METHOD: We evaluate modifications and alternatives to a state-of-the-art (SOTA) PVS segmentation method that uses a vesselness filter to enhance PVS discrimination, followed by thresholding of its response, applied to brain magnetic resonance images (MRI) from patients with sporadic small vessel disease acquired at 3 T.RESULTS: The method is robust against inter-observer differences in threshold selection, but separate thresholds for each region of interest (i.e., basal ganglia, centrum semiovale, and midbrain) are required. Noise needs to be assessed prior to selecting these thresholds, as effect of noise and imaging artefacts can be mitigated with a careful optimisation of these thresholds. PVS segmentation from T1-weighted images alone, misses small PVS, therefore, underestimates PVS count, may overestimate individual PVS volume especially in the basal ganglia, and is susceptible to the inclusion of calcified vessels and mineral deposits. Visual analyses indicated the incomplete and fragmented detection of long and thin PVS as the primary cause of errors, with the Frangi filter coping better than the Jerman filter.COMPARISON WITH EXISTING METHODS: Limits of validity to a SOTA PVS segmentation method applied to 3 T MRI with confounding pathology are given.CONCLUSIONS: Evidence presented reinforces the STRIVE-2 recommendation of using T2-weighted images for PVS assessment wherever possible. The Frangi filter is recommended for PVS segmentation from MRI, offering robust output against variations in threshold selection and pathology presentation.</p
    corecore