2,969 research outputs found

    Datos palinológicos de una turbera localizada en el Puerto de Canencia (Madrid)

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    Se presentan los primeros datos palinológicos obtenidos en el Puerto de Canencia\ud (Madrid). El estudio de esta zona nos va a permitir por un lado cubrir el vacío existente, en\ud el sector más oriental del Sistema Central, desde el punto de vista palinolólogico, así como poner de manifiesto la evolución y desarrollo de la vegetación de la zona, caracterizado por\ud la presencia de géneros de carácter relíctico eurosiberiano.It's presented the first palinologycal datas obtained in the Puerto de Canencia\ud (Madrid). The study of this zone will let us palliate the actual emptiness, from the\ud palinologycal point of view, in the most eastern part of the Sistema Central and show the evolution and development of the vegetation in this zone

    Synthesis and characterization of M(II) phosphonates (M = Fe, Co, Zn, Mn) as precursors for PEMFCs electrocatalysts

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    Metal phosphonates are promising precursors for applications such as proton conductivity [1] and catalysis [2]. Specifically, upon calcination metal polyphosphates are generated that can be used as non-noble metal alternatives [3] to the highly expensive commercial catalysts (Pt) for proton exchange membrane fuel cells (PEMFCs). In this work, we present the synthesis and characterization of metal polyphosphates obtained from transition divalent metal phosphonates (M= Fe, Mn, Co and Zn) both as monometallic and bimetallic systems (solid solutions). For the preparation of the metal phosphonate precursors, two types of organic linkers were selected, i.e. 2-R,S-hydroxiphosphonoacetic acid [HO3PCH(OH)COOH, HPAA] and nitrilotrismethylenephosphonic acid [N(CH2PO3H2)3, ATMP]. The as synthesized compounds were calcined between 700 and 1000 ºC under N2. Depending on the metal/phosphorous molar ratio in the precursor phases, different compositions were found, the corresponding metal pyrophosphate being the major component according to the crystallographic data. Interestingly, in most of cases the solid solutions were preserved in the final product, for instance Fe-Mn, Fe-Co and Fe-Zn. All calcined materials have been also characterized by XPS, SEM/EDS, FTIR-Raman.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    ‘I didn't feel like I was alone anymore’: evaluating self-organised employee coping practices conducted via Facebook

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    The long-term fracturing of the labour movement has led to increased attention to employee coping practices under new management practices and labour processes. However, the literature caters little for the recent rise of employees taking to social networking sites (SNSs), such as Facebook, to find ways to cope with the pressures of contemporary employment. To explore the self-organised coping qualities of SNSs, interviews were conducted with front line workers, employed by a large anti-trade union US retailer, who contribute to a self-organised Facebook group set up as a place for fellow employees to deal with collective employment-related problems. The main findings suggest employee self-organised Facebook groups represent an important development and extension to the coping practices available to individual and groups of employees. The main implication of the findings is that Facebook groups appear to strengthen and widen the options for employee resilience in an age of continuing trade union retreat

    Estimación de la velocidad de flujo del agua en cauces efímeros no aforados a partir de datos Lidar y GPS-RTK

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    The Manning formula is one of the most used to calculate the average velocity of water flow in ungauged channels. In order to be applied, it is necessary to measure in field the hydraulic radius (RH), the slope of the water surface (S), and to obtain the roughness coefficient (n), usually through tables created for this purpose. This involves a difficult, inefficient and subjective data collection in the field. This study evaluates the possibility to obtain these parameters in a more efficient manner, reducing the time of the process and allowing to work in larger areas. To achieve these objectives, the data used in this work were: 1) digital terrain models generated from airborne LiDAR data with a density of 2 points/ m2 , acquired when the channel was dry; 2) the height of the waterline and channel geometry measurements in the field using GPS; 3) Flow measurements. With this information, the velocity (Ve) was estimated and related to the average velocity of water flow (Vc) calculated from data measured in the field. The coefficient of determination between both velocity values was 73.52%, suggesting that the proposed methodology is useful to obtain the average velocity of flow, especially in remote areas or dry riverbeds

    Unveiling the structure of the planetary nebula M 2-48: Kinematics and physical conditions

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    The kinematics and physical conditions of the bipolar planetary nebula M 2-48 are analysed from high and low dispersion long-slit spectra. Previous CCD narrow-band optical observations have suggested that this nebula is mainly formed by a pair of symmetric bow-shocks, an off-center semi-circular shell, and an internal bipolar structure. The bipolar outflow has a complex structure, characterised by a series of shocked regions located between the bright core and the polar tips. There is an apparent kinematic discontinuity between the bright bipolar core and the outer regions. The fragmented ring around the bright bipolar region presents a low expansion velocity and could be associated to ejection in the AGB-PN transition phase, although its nature remains unclear. The chemical abundances of the central region are derived, showing that M 2-48 is a Type I planetary nebula (PN)

    Datos palinológicos de una turbera localizada en el Puerto de Canencia (Madrid)

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    Se presentan los primeros datos palinológicos obtenidos en el Puerto de Canencia (Madrid). El estudio de esta zona nos va a permitir por un lado cubrir el vacío existente, en el sector más oriental del Sistema Central, desde el punto de vista palinolólogico, así como poner de manifiesto la evolución y desarrollo de la vegetación de la zona, caracterizado por la presencia de géneros de carácter relíctico eurosiberiano.It's presented the first palinologycal datas obtained in the Puerto de Canencia (Madrid). The study of this zone will let us palliate the actual emptiness, from the palinologycal point of view, in the most eastern part of the Sistema Central and show the evolution and development of the vegetation in this zone

    Proteasome Dysfunction Associated to Oxidative Stress and Proteotoxicity in Adipocytes Compromises Insulin Sensitivity in Human Obesity

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    AIMS: Obesity is characterized by a low-grade systemic inflammatory state and adipose tissue (AT) dysfunction, which predispose individuals to the development of insulin resistance (IR) and metabolic disease. However, a subset of obese individuals, referred to as metabolically healthy obese (MHO) individuals, are protected from obesity-associated metabolic abnormalities. Here, we aim at identifying molecular factors and pathways in adipocytes that are responsible for the progression from the insulin-sensitive to the insulin-resistant, metabolically unhealthy obese (MUHO) phenotype. RESULTS: Proteomic analysis of paired samples of adipocytes from subcutaneous (SC) and omental (OM) human AT revealed that both types of cells are altered in the MUHO state. Specifically, the glutathione redox cycle and other antioxidant defense systems as well as the protein-folding machinery were dysregulated and endoplasmic reticulum stress was increased in adipocytes from IR subjects. Moreover, proteasome activity was also compromised in adipocytes of MUHO individuals, which was associated with enhanced accumulation of oxidized and ubiquitinated proteins in these cells. Proteasome activity was also impaired in adipocytes of diet-induced obese mice and in 3T3-L1 adipocytes exposed to palmitate. In line with these data, proteasome inhibition significantly impaired insulin signaling in 3T3-L1 adipocytes. INNOVATION: This study provides the first evidence of the occurrence of protein homeostasis deregulation in adipocytes in human obesity, which, together with oxidative damage, interferes with insulin signaling in these cells. CONCLUSION: Our results suggest that proteasomal dysfunction and impaired proteostasis in adipocytes, resulting from protein oxidation and/or misfolding, constitute major pathogenic mechanisms in the development of IR in obesity.IMIBIC/Universidad de Córdoba-SCAI (ProteoRed, PRB2-ISCIII)MINECO/FEDERJunta de Andalucía/FEDERCIBERobn(Instituto de Salud Carlos III

    The vitamin D decrease in children with obesity is associated with the development of insulin resistance during puberty: The PUBMEP study

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    Obesity and cardiometabolic risk have been associated with vitamin D levels even in children. The objective of the present study was to evaluate the association between insulin resistance (IR), cardiometabolic risk factors, and vitamin D in children from prepubertal to pubertal stages. A total of 76 children from the PUBMEP study, aged 4–12 years at baseline, were included. Children were evaluated in prepubertal and pubertal stages. Anthropometric measurements and selected cardiometabolic risk biomarkers, such as plasma glucose, blood lipids, insulin, adiponectin, leptin, and blood pressure, and serum 25-hydroxyvitamin D (25(OH)D) were determined. Children were categorized by obesity degree and IR status combined before and after puberty. Paired t-test and multivariate linear regression analyses were conducted. During puberty, the increase in triacylglycerols, insulin, and HOMA-IR and the decrease in QUICKI were significantly associated with the reduction in 25(OH)D (B = -0.274, p = 0.032; B = -0.219, p = 0.019; B = -0.250, p = 0.013; B = 1.574, p = 0.013, respectively) after adjustment by BMI-z, sex, and pubertal stage. Otherwise, prepubertal non-IR children with overweight/obesity that became IR during puberty showed a significant decrease in 25(OH)D and HDL-c, and an increase in waist circumference and triacylglycerol concentrations (p < 0.05 for all) over time. These results suggest that changes in IR seem to be associated with an effect on 25(OH)D levels during puberty, especially in children with overweight. © 2021 by the authors. Licensee MDPI, Basel, Switzerland
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