141 research outputs found

    Formulación química inorgánica en educación secundaria(poquer de química)

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    Uno de los principales problemas al que se enfrenta, en general, el profesorado de Ciencias Experimentales (en su labor de transmisor de conceptos) es la especificidad y dificultad que tiene, para el alumnado, la nomenclatura y epistemología utilizadas en las distintas áreas que conforman la Ciencia. Es a raíz de este problema práctico que planteamos la siguiente propuesta metodológica para la enseñanza de la Formulación Química Inorgánica en segundo ciclo de la E.S.O. En ella proponemos al alumnado que, con un juego de cartas, con su implicación directa y con un ambiente de aula abierto al intercambio de planteamientos y opiniones pueda construir su propio aprendizaje, en colaboración con sus compañeros/as y el profesorado. One of the main problems Science teachers must face while transmitting concepts is that Science nomenclature and epistemology is too specific and difficult for students. Starting from this practical problem we introduce the following methodological proposal to teach chemical formulae for inorganic compounds in the second cycle of the Secondary Education (E.S.O.). We aim at making our students build their own learning with the help of classmates and teachers. To do that, we use a card game which increases students involvement in the task and improves classroom atmosphere by offering students opportunities for exchanging approaches and/or opinions

    VentQsys: Low-cost open IoT system for CO2 monitoring in classrooms

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    In educational context, a source of nuisance for students is carbon dioxide (CO2) concentration due to closed rooms and lack of ventilation or circulatory air. Also, in the pandemic context, ventilation in indoor environments has been proven as a good tool to control the COVID-19 infections. In this work, it is presented a low cost IoT-based open-hardware and open-software monitoring system to control ventilation, by measuring carbon dioxide (CO2), temperature and relative humidity. This system provides also support for automatic updating, auto-self calibration and adds some Cloud and Edge offloading of computational features for mapping functionalities. From the tests carried out, it is observed a good performance in terms of functionality, battery durability, compared to other measuring devices, more expensive than our proposal

    Monochromatic neutrino beams

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    In the last few years spectacular results have been achieved with the demonstration of non vanishing neutrino masses and flavour mixing. The ultimate goal is the understanding of the origin of these properties from new physics. In this road, the last unknown mixing [Ue3] must be determined. If it is proved to be non-zero, the possibility is open for Charge Conjugation-Parity (CP) violation in the lepton sector. This will require precision experiments with a very intense neutrino source. Here a novel method to create a monochromatic neutrino beam, an old dream for neutrino physics, is proposed based on the recent discovery of nuclei that decay fast through electron capture. Such nuclei will generate a monochromatic directional neutrino beam when decaying at high energy in a storage ring with long straight sections. We also show that the capacity of such a facility to discover new physics is impressive, so that fine tuning of the boosted neutrino energy allows precision measurements of the oscillation parameters even for a [Ue3] mixing as small as 1 degree. We can thus open a window to the discovery of CP violation in neutrino oscillations

    Performance of Sulfonated Poly(Vinyl Alcohol)/Graphene Oxide Polyelectrolytes for Direct Methanol Fuel Cells

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    The use of nanotechnology along with the consideration of a functionalization and stabilization approach to poly(vinyl alcohol) (PVA) is considered useful for the preparation of cost-effective polyelectrolyte membranes. A set of nanocomposite and crosslinked membranes based on PVA/sulfosuccinic acid (SSA)/graphene oxide (GO) are prepared and analyzed as polyelectrolytes in direct methanol fuel cells (DMFCs). The crosslinking and sulfonation by the use of SSA enhances the stability and increase the proton-conducting sites in the PVA structure. The presence of GO augments the stability, remarkably decreases the methanol crossover, and enhances power density curves. An optimum value for proton conductivity is found for the 0.50 wt% of GO proportion, which decreases with higher concentrations of GO. Given the power density curve dependency on both the proton conductivity and the crossover reduction, the performance of these membranes as polyelectrolytes in DMFCs is strictly related to the balance between both factors. Therefore, a proportion of GO of 0.75 wt% may assure suitable proton conductivity of 3 mS cm−1 and high resistance to methanol permeability, reaching promising power density of 16 mW cm−2 with lower hydration levels

    The Vitamin D Receptor Regulates Glycerolipid and Phospholipid Metabolism in Human Hepatocytes

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    The vitamin D receptor (VDR) must be relevant to liver lipid metabolism because VDR deficient mice are protected from hepatosteatosis. Therefore, our objective was to define the role of VDR on the overall lipid metabolism in human hepatocytes. We developed an adenoviral vector for human VDR and performed transcriptomic and metabolomic analyses of cultured human hepatocytes upon VDR activation by vitamin D (VitD). Twenty percent of the VDR responsive genes were related to lipid metabolism, including MOGAT1, LPGAT1, AGPAT2, and DGAT1 (glycerolipid metabolism); CDS1, PCTP, and MAT1A (phospholipid metabolism); and FATP2, SLC6A12, and AQP3 (uptake of fatty acids, betaine, and glycerol, respectively). They were rapidly induced (4-6 h) upon VDR activation by 10 nM VitD or 100 µM lithocholic acid (LCA). Most of these genes were also upregulated by VDR/VitD in mouse livers in vivo. Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS) metabolomics demonstrated intracellular accumulation of triglycerides, with concomitant decreases in diglycerides and phosphatidates, at 8 and 24 h upon VDR activation. Significant alterations in phosphatidylcholines, increases in lyso-phosphatidylcholines and decreases in phosphatidylethanolamines and phosphatidylethanolamine plasmalogens were also observed. In conclusion, active VitD/VDR signaling in hepatocytes triggers an unanticipated coordinated gene response leading to triglyceride synthesis and to important perturbations in glycerolipids and phospholipids

    Salud mental autopercibida e informada en personas mayores

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    Several studies assess mental health in older adults, but relatively few do so from a multi-informant perspective. In this work, discrepancies in self-perception and   third-person perception of the mental health of older adults were analyzed in two age groups and differentiated by sex and place of residence. Relationships between different scales that measure psychopathology and psychosocial competencies were also analyzed. A sample of 288 older people aged between 60-95 years old (154 women, 53.47%) belonging to 12 municipalities in the Region of Murcia was employed, and the Older Adult Self-Report (OASR) questionnaire was used to measure the psychopathology of older people and the Older Adult Behavior Checklist (OABCL) instrument to find out the family's perception of these problems. Outcomes show different perceptions of mental health among older people and their families, which worsen with increasing age, psychosocial risk status and female gender. This reflects the need to develop specific treatment protocols for each gender and psychosocial risk situation, in order to address the differential mental health needs in older people.Son numerosos los trabajos que evalúan la salud mental de las personas mayores, pero relativamente escasos los que lo hacen desde una perspectiva multi-informante. En este trabajo se analizaron las discrepancias en la autopercepción y la percepción que tienen otros de la salud mental de las personas mayores, en dos franjas de edad, diferenciando por sexos, lugar de residencia y se analizaron las relaciones entre diferentes escalas que miden psicopatología y competencias psicosociales. Se empleó una muestra de 288 personas mayores entre 60-95 años (154 mujeres, 53.47%) pertenecientes a 12 municipios de la Región de Murcia, y se empleó el cuestionario OlderAdultSelf-Report (OASR) para medir la psicopatología de las personas mayores y el instrumentoOlderAdultBehaviorChecklist (OABCL) para conocer la percepción de la familia de estos problemas. Los resultados reflejan que existen diferentes percepciones de la salud mental entre personas mayores y sus familiares, que empeoran al aumentar la edad, la situación de riesgo psicosocial y el género femenino. Esto refleja la necesidad de desarrollar protocolos de tratamiento específicos para cada género y situación de riesgo psicosocial, con el fin de atender las necesidades diferenciales de salud mental de las personas mayores

    Towards a Rapid Screening of Liver Grafts at the Operating Room Using Mid-Infrared Spectroscopy

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    The estimation of steatosis in a liver graft is mandatory prior to liver transplantation, as the risk of graft failure increases with the level of infiltrated fat. However, the assessment of liver steatosis before transplantation is typically based on a qualitative or semiquantitative characterization by visual inspection and palpation and histological analysis. Thus, there is an unmet need for transplantation surgeons to have access to a diagnostic tool enabling an in situ fast classification of grafts prior to extraction. In this study, we have assessed an attenuated total reflection−Fourier transform infrared (ATR−FTIR) spectroscopic method compatible with the requirements of an operation room for the evaluation of the lipid content in human livers. A set of human liver biopsies obtained from organs intended for transplantation were analyzed by expert pathologists, ATR−FTIR spectroscopy, lipid biochemical analysis, and UPLC−ESI(+/−)TOFMS for lipidomic profiling. Comparative analysis of multisource data showed strong correlations between ATR−FTIR, clinical, and lipidomic information. Results show that ATR−FTIR captures a global picture of the lipid composition of the liver, along with information for the quantification of the triradylglycerol content in liver biopsies. Although the methodology performance needs to be further validated, results support the applicability of ATR−FTIR for the in situ determination of the grade of liver steatosis at the operation room as a fast, quantitative method, as an alternative to the qualitative and subjective pathological examination

    Small-Packet Flows in Software Defined Networks: Traffic Profile Optimization

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    This paper proposes a method for optimizing bandwidth usage in Software Defined Networks (SDNs) based on OpenFlow. Flows of small packets presenting a high overhead, as the ones generated by emerging services, can be identified by the SDN controller, in order to remove header fields that are common to any packet in the flow, only during their way through the SDN. At the same time, several packets can be multiplexed together in the same frame, thus reducing the overall number of frames. The method can be useful for providing QoS while the packets are traversing the SDN. Four kinds of small-packet traffic flows are considered (VoIP, UDP and TCP-based online games, and ACKs from TCP flows). Both IPv4 and IPv6 are studied, and significant bandwidth savings (up to 68 % for IPv4 and 78 % for IPv6) can be obtained for the considered kinds of traffic. The optimization method is also applied to different public Internet traffic traces, and significant reductions in terms of packets per second are achieved. Results show that bandwidth consumption is also reduced, especially in those traces where the percentage of small packets is high. Regarding the effect on QoS, the additional delay can be kept very low (below 1 millisecond) when the throughput is high, but it may become significant for low- throughput scenarios. Thus, a trade-off between bandwidth saving and additional delay appears in those cases

    Optimization of low-efficiency traffic in OpenFlow Software Defined Networks

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    Abstract — This paper proposes a method for optimizing bandwidth usage in Software Defined Networks (SDNs) based on OpenFlow. Flows of small packets presenting a high overhead, as the ones generated by emerging services, can be identified by the SDN controller, in order to remove header fields that are common to any packet in the flow, only during their way through the SDN. At the same time, several packets can be multiplexed together in the same frame, thus reducing the number of sent frames. Four kinds of small-packet traffic flows are considered (VoIP, UDP and TCP-based online games, and ACKs from TCP flows). Both IPv4 and IPv6 are tested, and significant bandwidth savings (up to 68 % for IPv4 and 78 % for IPv6) can be obtained for the considered kinds of traffic

    Obstructive Sleep Apnoea Syndrome, Endothelial Function and Markers of Endothelialization. Changes after CPAP

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    Study objectives This study tries to assess the endothelial function in vivo using flow-mediated dilatation (FMD) and several biomarkers of endothelium formation/restoration and damage in patients with obstructive sleep apnoea (OSA) syndrome at baseline and after three months with CPAP therapy. Design Observational study, before and after CPAP therapy. Setting and Patients We studied 30 patients with apnoea/hypopnoea index (AHI) > 15/h that were compared with themselves after three months of CPAP therapy. FMD was assessed non-invasively in vivo using the Laser-Doppler flowmetry. Circulating cell-free DNA (cf-DNA) and microparticles (MPs) were measured as markers of endothelial damage and the vascular endothelial growth factor (VEGF) was determined as a marker of endothelial restoration process. Measurements and results After three month with CPAP, FMD significantly increased (1072.26 +/- 483.21 vs. 1604.38 +/- 915.69 PU, p<0.005) cf-DNA and MPs significantly decreased (187.93 +/- 115.81 vs. 121.28 +/- 78.98 pg/ml, p<0.01, and 69.60 +/- 62.60 vs. 39.82 +/- 22.14 U/mu L, p<0.05, respectively) and VEGF levels increased (585.02 +/- 246.06 vs. 641.11 +/- 212.69 pg/ml, p<0.05). These changes were higher in patients with more severe disease. There was a relationship between markers of damage (r = -0.53, p< 0.005) but not between markers of damage and restoration, thus suggesting that both types of markers should be measured together. Conclusions CPAP therapy improves FMD. This improvement may be related to an increase of endothelial restoration process and a decrease of endothelial damage
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