1,246 research outputs found

    La Investigación En La Práctica Pedagógica De Los Docentes De Educación Media

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    La investigación docente no debe estar limitada a campos específicos de las universidades, por el contrario, es pertinente que los docentes en todos los niveles educativos del sistema escolar, apoyen su práctica pedagógica con la realización de estudios que sistematicen sus experiencias y contribuyan al campo de la educación. El presente artículo exhibe los desarrollos de la tesis doctoral Aproximación Teórica a la Investigación en la Práctica Pedagógica de los Docentes de Educación Media, para el cual se asume una visión epistemológica constructivista, con metodología hermenéutico dialéctica, bajo el paradigma cualitativo y se sigue el método de la teoría fundamentada para el análisis de datos y la generación teórica. El estudio concluye con la presentación de la aproximación teórica según el constructo emergente que se revela en relación a la investigación en la práctica pedagógica de los docentes de educación media

    Wunderlich syndrome (spontaneous renal hematoma) as a cause of acute abdomen: a case report

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    Spontaneous renal hemorrhage, also known as Wünderlich syndrome, is a rare condition that can be life-threatening and consists of the onset of sudden hemorrhage into the subcapsular and perirenal spaces. It can be lethal as it goes unnoticed and requires aggressive treatment. The entity lies mainly in neoplasms, the malignant ones being the most common. We present the case of a 63-year-old female patient with acute abdomen clinic, a diagnostic laparoscopy was performed and renal hematoma was evidenced as the cause of the symptoms. It was managed conservatively without any complications. We emphasize the importance of keeping in mind Wünderlich syndrome as a differential diagnosis to instigate early treatment for a better outcome.

    Potential of ORC Systems to Retrofit CHP Plants in Wastewater Treatment Stations

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    Wastewater treatment stations take advantage of the biogas produced from sludge in anaerobic digesters to generate electricity (reciprocating gas engines) and heat (cooling water and engine exhaust gases). A fraction of this electricity is used to operate the plant while the remaining is sold to the grid. Heat is almost entirely used to support the endothermic anaerobic digestion and a minimum fraction of it is rejected to the environment at a set of fan coolers. This generic description is applicable to on-design conditions. Nevertheless, the operating conditions of the plant present a large seasonal variation so it is commonly found that the fraction of heat rejected to the atmosphere increases significantly at certain times of the year. Moreover, the heat available in the exhaust gases of the reciprocating engine is at a very high temperature (around 650 ºC), which is far from the temperature at which heat is needed for the digestion of sludge (around 40 ºC in the digesters). This temperature difference offers an opportunity to introduce an intermediate system between the engines and the digesters that makes use of a fraction of the available heat to convert it into electricity. An Organic Rankine Cycle (ORC) with an appropriate working fluid is an adequate candidate for these hot/cold temperature sources. In this paper, the techno-economic effect of adding an Organic Rankine Cycle as the intermediate system of an existing wastewater treatment station is analysed. On this purpose, different working fluids and system layouts have been studied for a reference wastewater treatment station giving rise to optimal systems configurations. The proposed systems yield very promising results with regard to global efficiency and electricity production (thermodynamically and economically)

    New GTC spectroscopic data and a statistical study to better constrain the redshift of the BL Lac RGB J2243 + 203

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    We present new spectroscopic data of the BL Lac RGB 2243 + 203, and its surroundings, obtained with the OSIRIS Multi Object Spectrograph (MOS) mounted in the Gran Telescopio Canarias (GTC). The spectra of neither the BL Lac nor its host galaxy show any spectral feature, thus hindering direct determination of its redshift. The spectroscopic redshift distribution of objects in the MOS field of view shows four galaxies with redshift between 0.5258 and 0.5288. We make use of a statistical analysis to test the possibility that the targeted BL Lac may be a member of that group. By using the spectroscopic redshifts obtained with our GTC observations, we found that this probability is between 86 and 93 per cent.Fil: Rosa González, D. Instituto Nacional de Astrofísica, Optica y Electrónica; MéxicoFil: Muriel, Hernan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Mayya, Y. D.. Instituto Nacional de Astrofísica, Optica y Electrónica; MéxicoFil: Aretxaga, I.. Instituto Nacional de Astrofísica, Optica y Electrónica; MéxicoFil: Becerra González, J.. Instituto de Astrofisica de Canarias; EspañaFil: Carramiñana, Alberto. Instituto Nacional de Astrofísica, Optica y Electrónica; MéxicoFil: Méndez-Abreu, J.. Instituto Nacional de Astrofísica, Optica y Electrónica; MéxicoFil: Vega, O. Instituto Nacional de Astrofísica, Optica y Electrónica; MéxicoFil: Terlevich, E-. Instituto Nacional de Astrofísica, Optica y Electrónica; MéxicoFil: Coutiño de León, S.. Instituto Nacional de Astrofísica, Optica y Electrónica; MéxicoFil: Furniss, A.. Instituto Nacional de Astrofísica, Optica y Electrónica; MéxicoFil: Longinotti, A. L.. Instituto Nacional de Astrofísica, Optica y Electrónica; MéxicoFil: Terlevich, R. J.. Instituto Nacional de Astrofísica, Optica y Electrónica; MéxicoFil: Pichel, Ana Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Rovero, Adrian Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Donzelli, Carlos Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; Argentin

    Natural estrogens enhance the engraftment of human hematopoietic stem and progenitor cells in immunodeficient mice

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    Hematopoietic Stem and Progenitor Cells are crucial in the maintenance of lifelong production of all blood cells. These Stem Cells are highly regulated to maintain homeostasis through a delicate balance between quiescence, self-renewal and differentiation. However, this balance is altered during the hematopoietic recovery after Hematopoietic Stem and Progenitor Cell Transplantation. Transplantation efficacy can be limited by inadequate Hematopoietic Stem Cells number, poor homing, low level of engraftment, or limited self-renewal. As recent evidences indicate that estrogens are involved in regulating the hematopoiesis, we sought to examine whether natural estrogens (estrone or E1, estradiol or E2, estriol or E3 and estetrol or E4) modulate human Hematopoietic Stem and Progenitor Cells. Our results show that human Hematopoietic Stem and Progenitor Cell subsets express estrogen receptors, and whose signaling is activated by E2 and E4 on these cells. Additionally, these natural estrogens cause different effects on human Progenitors in vitro. We found that both E2 and E4 expand human Hematopoietic Stem and Progenitor Cells. However, E4 was the best tolerated estrogen and promoted cell cycle of human Hematopoietic Progenitors. Furthermore, we identified that E2 and, more significantly, E4 doubled human hematopoietic engraftment in immunodeficient mice without altering other Hematopoietic Stem and Progenitor Cells properties. Finally, the impact of E4 on promoting human hematopoietic engraftment in immunodeficient mice might be mediated through the regulation of mesenchymal stromal cells in the bone marrow niche. Together, our data demonstrate that E4 is well tolerated and enhances human reconstitution in immunodeficient mice, directly by modulating human Hematopoietic Progenitor properties and indirectly by interacting with the bone marrow niche. This application might have particular relevance to ameliorate the hematopoietic recovery 3 after myeloablative conditioning, especially when limiting numbers of Hematopoietic Stem and Progenitor Cells are available

    Skeletal diseases caused by mutations in PTH1R show aberrant differentiation of skeletal progenitors due to dysregulation of DEPTOR

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    Alterations in the balance between skeletogenesis and adipogenesis is a pathogenic feature in multiple skeletal disorders. Clinically, enhanced bone marrow adiposity in bones impairs mobility and increases fracture risk, reducing the quality of life of patients. The molecular mechanism that underlies the balance between skeletogenesis and adipogenesis is not completely understood but alterations in skeletal progenitor cells’ differentiation pathway plays a key role. We recently demonstrated that parathyroid hormone (PTH)/PTH-related peptide (PTHrP) control the levels of DEPTOR, an inhibitor of the mechanistic target of rapamycin (mTOR), and that DEPTOR levels are altered in different skeletal diseases. Here, we show that mutations in the PTH receptor-1 (PTH1R) alter the differentiation of skeletal progenitors in two different skeletal genetic disorders and lead to accumulation of fat or cartilage in bones. Mechanistically, DEPTOR controls the subcellular localization of TAZ (transcriptional co-activator with a PDZ-binding domain), a transcriptional regulator that governs skeletal stem cells differentiation into either bone and fat. We show that DEPTOR regulation of TAZ localization is achieved through the control of Dishevelled2 (DVL2) phosphorylation. Depending on nutrient availability, DEPTOR directly interacts with PTH1R to regulate PTH/PTHrP signaling or it forms a complex with TAZ, to prevent its translocation to the nucleus and therefore inhibit its transcriptional activity. Our data point DEPTOR as a key molecule in skeletal progenitor differentiation; its dysregulation under pathologic conditions results in aberrant bone/fat balance

    A Reemerging Bright Soft X-Ray State of the Changing-look Active Galactic Nucleus 1ES 1927+654:A Multiwavelength View

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    1ES1927+654 is a nearby active galactic nucleus (AGN) that has shown an enigmatic outburst in optical/UV followed by X-rays, exhibiting strange variability patterns at timescales of months to years. Here we report the unusual X-ray, UV, and radio variability of the source in its postflare state (2022 January–2023 May). First, we detect an increase in the soft X-ray (0.3–2 keV) flux from 2022 May to 2023 May by almost a factor of 5, which we call the bright soft state. The hard X-ray 2–10 keV flux increased by a factor of 2, while the UV flux density did not show any significant changes (≤30%) in the same period. The integrated energy pumped into the soft and hard X-rays during this period of 11 months is ∼3.57 × 10 ^50 erg and 5.9 × 10 ^49 erg, respectively. From the energetics, it is evident that whatever is producing the soft excess (SE) is pumping out more energy than either the UV or hard X-ray source. Since the energy source presumably is ultimately the accretion of matter onto the supermassive black hole, the SE-emitting region must be receiving the majority of this energy. In addition, the source does not follow the typical disk–corona relation found in AGNs, neither in the initial flare (from 2017 to 2019) nor in the current bright soft state (2022–2023). We found that the core (<1 pc) radio emission at 5 GHz gradually increased until 2022 March, but showed a dip in 2022 August. The Güdel–Benz relation ( L _radio / L _X-ray ∼ 10 ^−5 ), however, is still within the expected range for radio-quiet AGNs, and further follow-up radio observations are currently being undertaken

    Unexpected decline in tuberculosis cases coincident with economic recession -- United States, 2009

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    <p>Abstract</p> <p>Background</p> <p>Since 1953, through the cooperation of state and local health departments, the U.S. Centers for Disease Control and Prevention (CDC) has collected information on incident cases of tuberculosis (TB) disease in the United States. In 2009, TB case rates declined -11.4%, compared to an average annual -3.8% decline since 2000. The unexpectedly large decline raised concerns that TB cases may have gone unreported. To address the unexpected decline, we examined trends from multiple sources on TB treatment initiation, medication sales, and laboratory and genotyping data on culture-positive TB.</p> <p>Methods</p> <p>We analyzed 142,174 incident TB cases reported to the U. S. National Tuberculosis Surveillance System (NTSS) during January 1, 2000-December 31, 2009; TB control program data from 59 public health reporting areas; self-reported data from 50 CDC-funded public health laboratories; monthly electronic prescription claims for new TB therapy prescriptions; and complete genotyping results available for NTSS cases. Accounting for prior trends using regression and time-series analyses, we calculated the deviation between observed and expected TB cases in 2009 according to patient and clinical characteristics, and assessed at what point in time the deviation occurred.</p> <p>Results</p> <p>The overall deviation in TB cases in 2009 was -7.9%, with -994 fewer cases reported than expected (<it>P </it>< .001). We ruled out evidence of surveillance underreporting since declines were seen in states that used new software for case reporting in 2009 as well as states that did not, and we found no cases unreported to CDC in our examination of over 5400 individual line-listed reports in 11 areas. TB cases decreased substantially among both foreign-born and U.S.-born persons. The unexpected decline began in late 2008 or early 2009, and may have begun to reverse in late 2009. The decline was greater in terms of case counts among foreign-born than U.S.-born persons; among the foreign-born, the declines were greatest in terms of percentage deviation from expected among persons who had been in the United States less than 2 years. Among U.S.-born persons, the declines in percentage deviation from expected were greatest among homeless persons and substance users. Independent information systems (NTSS, TB prescription claims, and public health laboratories) reported similar patterns of declines. Genotyping data did not suggest sudden decreases in recent transmission.</p> <p>Conclusions</p> <p>Our assessments show that the decline in reported TB was not an artifact of changes in surveillance methods; rather, similar declines were found through multiple data sources. While the steady decline of TB cases before 2009 suggests ongoing improvement in TB control, we were not able to identify any substantial change in TB control activities or TB transmission that would account for the abrupt decline in 2009. It is possible that other multiple causes coincident with economic recession in the United States, including decreased immigration and delayed access to medical care, could be related to TB declines. Our findings underscore important needs in addressing health disparities as we move towards TB elimination in the United States.</p

    Contribution of cardio-vascular risk factors to depressive status in the PREDIMED-PLUS Trial. A cross-sectional and a 2-year longitudinal study

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    Background Cardio-vascular disease and depression are thought to be closely related, due to shared risk factors. The aim of the study was to determine the association between cardio-vascular risk (CVR) factors and depressive status in a population (55-75 years) with metabolic syndrome (MetS) from the PREDIMED-Plus trial. Methods and findings Participants were classified into three groups of CVR according to the Framingham-based REGICOR function: (1) low (LR), (2) medium (MR) or (3) high/very high (HR). The Beck Depression Inventory-II (BDI-II) was used to assess depressive symptoms at baseline and after 2 years. The association between CVR and depressive status at baseline (n = 6545), and their changes after 2 years (n = 4566) were evaluated through multivariable regression models (logistic and linear models). HR women showed higher odds of depressive status than LR [OR (95% CI) = 1.78 (1.26, 2.50)]. MR and HR participants with total cholesterol <160 mg/mL showed higher odds of depression than LR [OR (95% CI) = 1.77 (1.13, 2.77) and 2.83 (1.25, 6.42) respectively)] but those with total cholesterol ¿280 mg/mL showed lower odds of depression than LR [OR (95% CI) = 0.26 (0.07, 0.98) and 0.23 (0.05, 0.95), respectively]. All participants decreased their BDI-II score after 2 years, being the decrease smaller in MR and HR diabetic compared to LR [adjusted mean±SE = -0.52±0.20, -0.41 ±0.27 and -1.25±0.31 respectively). MR and HR participants with total cholesterol between 240-279 mg/mL showed greater decreases in the BDI-II score compared to LR (adjusted mean±SE = -0.83±0.37, -0.77±0.64 and 0.97±0.52 respectively). Conclusions Improving cardiovascular health could prevent the onset of depression in the elderly. Diabetes and total cholesterol in individuals at high CVR, may play a specific role in the precise response.The PREDIMED-Plus trial was supported by the European Research Council through a grant to MAM (Advanced Research Grant 2013-2018; 340918). The project was also supported by the official funding agency for biomedical research of the Spanish Government (ISCIII) through the Fondo de Investigación para la Salud (FIS), which is co-funded by the European Regional Development Fund (four coordinated FIS projects), who awarded grants to JS and JV (PI13/00673, PI13/00492, PI13/00272, PI13/01123, PI13/00462, PI13/00233, PI13/02184, PI13/00728, PI13/01090, PI13/01056, PI14/01722, PI14/00636, PI14/00618, PI14/00696, PI14/01206, PI14/01919, PI14/00853, PI14/01374, PI16/00473, PI16/00662, PI16/01873, PI16/01094, PI16/00501, PI16/00533, PI16/00381, PI16/00366, PI16/01522, PI16/01120, PI17/00764, PI17/01183, PI17/00855, PI17/01347, PI17/00525, PI17/01827, PI17/00532, PI17/00215, PI17/01441, PI17/00508, PI17/01732 and PI17/00926). The International Nut&Dried Fruit Council-FESNAD also provided funding through a grant to MAM (201302), and Recercaixa also awarded a grant to JS (2013ACUP00194). The Department of Health, Generalitat de Cataluña by the calls 'Acció instrumental de programes de recerca orientats en lámbit de la recercaila innovació en salut' and 'Pla estrategic de recerca i innovació en salut (PERIS),' also awarded a grant to FF (SLT006/17/00246). This research was also partially funded by: Consejería de Salud de la Junta de Andalucía (PI0458/2013, PS0358/2016, PI0137/2018); Generalitat Valenciana (PROMETEO/2017/017); SEMERGEN, CIBEROBN, FEDER and ISCIII (CB06/03); EU-H2020 Grants (Eat2beNICE/h2020-sfs-2016-2, ref.728018; PRIME/h2020-SC1-BHC-2018-2020, ref: 847879)

    Multiwavelength study of quiescent states of MRK 421 with unprecedented hard x-ray coverage provided by<i> NuSTAR</i> in 2013

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