126 research outputs found

    Aprendizajes conceptuales alcanzados por los estudiantes de tres escuelas rurales en Chipatá- Santander en relación a la ecología y conservación de las aves

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    En este trabajo se divulgan los resultados parciales del proyecto “contribución a laconstrucción del concepto de ‹Conservación de Aves› por parte de los estudiantes de tressedes rurales del Instituto Técnico Agropecuario “Agatá” en el municipio de Chipatá-Santander“ ; donde se vinculan la escuela rural y la enseñanza-aprendizaje de lasciencias para la conservación de la biodiversidad. Se implementó una unidad didácticabajo el enfoque de la investigación escolar. Los aprendizajes conceptuales logradosfueron analizados mediante categorías; se encontró que estos contribuyen a laconstrucción del concepto de conservación de aves enfocado a su función demantenimiento y equilibrio en el ecosistema

    Neuronal accumulation of unrepaired DNA in a novel specific chromatin domain: structural, molecular and transcriptional characterization

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    There is growing evidence that defective DNA repair in neurons with accumulation of DNA lesions and loss of genome integrity underlies aging and many neurodegenerative disorders. An important challenge is to understand how neurons can tolerate the accumulation of persistent DNA lesions without triggering the apoptotic pathway. Here we study the impact of the accumulation of unrepaired DNA on the chromatin architecture, kinetics of the DNA damage response and transcriptional activity in rat sensory ganglion neurons exposed to 1-to-3 doses of ionizing radiation (IR). In particular, we have characterized the structural, molecular and transcriptional compartmentalization of unrepaired DNA in persistent DNA damaged foci (PDDF). IR induced the formation of numerous transient foci, which repaired DNA within the 24 h post-IR, and a 1-to-3 PDDF. The latter concentrate DNA damage signaling and repair factors, including ?H2AX, pATM, WRAP53 and 53BP1. The number and size of PDDF was dependent on the doses of IR administered. The proportion of neurons carrying PDDF decreased over time of post-IR, indicating that a slow DNA repair occurs in some foci. The fine structure of PDDF consisted of a loose network of unfolded 30 nm chromatin fiber intermediates, which may provide a structural scaffold accessible for DNA repair factors. Furthermore, the transcription assay demonstrated that PDDF are transcriptionally silent, although transcription occurred in flanking euchromatin. Therefore, the expression of ?H2AX can be used as a reliable marker of gene silencing in DNA damaged neurons. Moreover, PDDF were located in repressive nuclear environments, preferentially in the perinucleolar domain where they were frequently associated with Cajal bodies or heterochromatin clumps forming a structural triad. We propose that the sequestration of unrepaired DNA in discrete PDDF and the transcriptional silencing can be essential to preserve genome stability and prevent the synthesis of aberrant mRNA and protein products encoded by damaged genes

    Daylight luminescence system for silicon solar panels based on a bias switching method

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    Among the many characterization techniques for solar panel testing, two, electroluminescence (EL) and photoluminescence (PL), can provide useful visual information about the presence of different types of cell defects. EL is performed outdoors by night in commercial solar plants due to the very weak luminescence emission compared to sunlight. PL faces the added difficulty of needing to find a large-area homogeneous light source to excite the modules. Since nighttime work poses many drawbacks and risks, a daylight outdoor EL/PL system would be useful for offering safe inspection of solar plants. We present daylight luminescence techniques based on a bias switching method, in which a pulsed luminescence signal is obtained by alternating the polarization state of the solar panels, synchronizing it with the luminescence image detection by an InGaAs camera. Fast switching and selecting an optimized exposure time are key to achieving high-quality images. The daylight luminescence method described herein allows both EL and PL luminescence images to be obtained, even under high solar irradiance conditions.Proyecto de Investigación ENE2014-56069-C4- 4-R (MCIN)Proyecto de Investigación ENE2017-89561-C4-3-R (MCIN)Proyecto de Investigación RTC-2017-6712-3 (MCIN)Proyecto IDI-20151194 (CDTI)Proyecto de Investigación VA081U16 (Junta de Castilla y León)Proyecto de Investigación VA283P18 (Junta de Castilla y León

    Persistent accumulation of unrepaired DNA damage in rat cortical neurons: nuclear organization and ChIP-seq analysis of damaged DNA

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    Neurons are highly vulnerable to DNA damage induced by genotoxic agents such as topoisomerase activity, oxidative stress, ionizing radiation (IR) and chemotherapeutic drugs. To avert the detrimental effects of DNA lesions in genome stability, transcription and apoptosis, neurons activate robust DNA repair mechanisms. However, defective DNA repair with accumulation of unrepaired DNA are at the basis of brain ageing and several neurodegenerative diseases. Understanding the mechanisms by which neurons tolerate DNA damage accumulation as well as defining the genomic regions that are more vulnerable to DNA damage or refractory to DNA repair and therefore constitute potential targets in neurodegenerative diseases are essential issues in the field. In this work we investigated the nuclear topography and organization together with the genome-wide distribution of unrepaired DNA in rat cortical neurons 15 days upon IR. About 5% of non-irradiated and 55% of irradiated cells accumulate unrepaired DNA within persistent DNA damage foci (PDDF) of chromatin. These PDDF are featured by persistent activation of DNA damage/repair signaling, lack of transcription and localization in repressive nuclear microenvironments. Interestingly, the chromatin insulator CTCF is concentrated at the PDDF boundaries, likely contributing to isolate unrepaired DNA from intact transcriptionally active chromatin. By confining damaged DNA, PDDF would help preserving genomic integrity and preventing the production of aberrant proteins encoded by damaged genes.ChIP-seq analysis of genome-wide ?H2AX distribution revealed a number of genomic regions enriched in ?H2AX signal in IR-treated cortical neurons. Some of these regions are in close proximity to genes encoding essential proteins for neuronal functions and human neurodegenerative disorders such as epm2a (Lafora disease), serpini1 (familial encephalopathy with neuroserpin inclusion bodies) and il1rpl1 (mental retardation, X-linked 21). Persistent ?H2AX signal close to those regions suggests that nearby genes could be either more vulnerable to DNA damage or more refractory to DNA repair.This work was supported by the following grants: “Dirección General de Investigación” (BFU2014–54754-P) and “Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas” (CIBERNED; CB06/05/0037) Spain

    Actitudes metacognitivas y de trabajo en equipo alcanzadas por los estudiantes de tres escuelas rurales en chipatá- santander en relación al concepto de conservación en aves

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    En el presente trabajo se muestran algunos de los resultados del proyecto “contribución a la construcción del concepto de Conservación de Aves por parte de los estudiantes de tres sedes rurales del Instituto Técnico Agropecuario “Agatá” en el municipio de Chipatá- Santander “, donde se vincula a la escuela rural y la enseñanza-aprendizaje de las ciencias en la conservación de la biodiversidad. Se implementó una unidad didáctica bajo el enfoque de la investigación escolar. Los aprendizajes actitudinales logrados fueron categorizados, encontrando aportan a la construcción del concepto de conservación de aves ya que dichas actitudes resultan significativas en el conocimiento, manejo e importancia del papel en cuanto a las relaciones ecosistémicas de estos organismos juegan en su contexto, fortaleciendo de esta manera procesos metacognitivos y de trabajo en equipo

    Residual Strain and Electrical Activity of Defects in Multicrystalline Silicon Solar Cells

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    Producción CientíficaThe growth process by casting methods of multi-crystalline Si results in a crystalline material with, among other defects, a high density of dislocations and grain boundaries. Impurity incorporation and their gathering around grain boundaries and dislocations seem to be the main factor determining the electrical activity of those defects, which limit the minority carrier lifetime. In this work, we analyze multi-crystalline Si samples by combining etching processes to reveal the defects, Raman spectroscopy for strain measurements, and light beam induced current measurements for the localization of electrically active defects. In particular, we have explored the etching routes capable to reveal the main defects (grain boundaries and dislocation lines), while their electrical activity is studied by the light beam induced current technique. We further analyze the strain levels around these defects by Raman micro-spectroscopy, aiming to obtain a more general picture of the correlation between residual stress and electrical activity of the extended defects. The higher stress levels are observed around intra-grain defects associated with dislocation lines, rather than around the grain boundaries. On the other hand, the intra-grain defects are also observed to give dark light beam induced current contrast associated with a higher electrical activity of these defects as compared to the grain boundariesJunta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. A166A11-2)Ministerio de Ciencia e innovación (IPT-420000-2010- -022 INNPACTO program

    The Spanish version of the reflective functioning questionnaire: Validity data in the general population and individuals with personality disorders.

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    Introduction Mentalization or reflective functioning (RF) is the capacity to interpret oneself or the others in terms of internal mental states. Its failures have been linked to several mental disorders and interventions improving RF have a therapeutic effect. Mentalizing capacity of the parents influences the children’s attachment. The Reflective Functioning Questionnaire (RFQ-8) is a widely used tool for the assessment of RF. No instrument is available to assess general RF in Spanish-speaking samples. The aim of this study is to develop a Spanish version of the RFQ-8 and to evaluate its reliability and validity in the general population and in individuals with personality disorders. Methods 602 non-clinical and 41 personality disordered participants completed a Spanish translation of the RFQ and a battery of self-reported questionnaires assessing several RF related constructs (alexithymia, perspective taking, identity diffusion and mindfulness), psychopathology (general and specific) and interpersonal problems. Temporal stability was tested in a non-clinical sub-sample of 113 participants. Results Exploratory and confirmatory factor analyses suggested a one-factor structure in the Spanish version of the RFQ-8. RFQ-8 understood as a single scale was tested, with low scorings reflecting genuine mentalizing, and high scorings uncertainty. The questionnaire showed good internal consistence in both samples and moderate temporal stability in non-clinical sample. RFQ correlated significantly with identity diffusion, alexithymia, and general psychopathology in both samples; and with mindfulness, perspective taking, and interpersonal problems in clinical sample. Mean values of the scale were significantly higher in the clinical group. Discussion This study provides evidence that the Spanish version of the RFQ-8, understood as a single scale, has an adequate reliability and validity assessing failures in reflective functioning (i.e., hypomentalization) in general population and personality disorders.The study received a Health Strategic Action fund from the Carlos III Health Institute of the Spanish Ministry of Science and Innovation. ID PI16/02058. https://www.isciii.es/QueHacemos/Financiacion/solicitudes/Paginas/default.aspx No researcher have received money from the fund. This kind of public funds are managed by public institutes (in this case BIOEF) that ensure this money is only used for some of the material resources necessary to carry out the investigation. https://www.bioef.org/es/ The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Sequential priming in the detection of the facial expression: New approach in the study of emotional detection

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    La eficacia en la detección de las expresiones faciales que nos alertan de una posible amenaza es adaptativa. Por esta razón, los estudios sobre rastreo facial se han interesado en el análisis de este proceso, encontrándose evidencias de que la mirada se enfoca prioritariamente a la parte superior del rostro; sin embargo, no se ha establecido de manera clara la relación entre la eficacia en la detección (velocidad y precisión) y la forma en la que se rastrean las expresiones faciales emocionales. Con el objetivo de aportar claridad en este punto, se realizó una tarea de priming secuencial en la que se mostraban los cuatro cuadrantes de la cara de manera consecutiva, durante 50 ms cada uno, y en un orden diferente (24 secuencias). Los resultados mostraron una respuesta más rápida cuando las secuencias de priming comenzaban en la parte superior, continuaban hacia abajo en el lado derecho, y posteriormente seguían la dirección contraria a la agujas del reloj. Se discuten los resultados a la luz de los estudios que utilizan la técnica de EyeTracking.VI Convocatoria de Ayudas a la Investigación UCJ

    Clinical Factors Associated with Reinfection versus Relapse in Infective Endocarditis: Prospective Cohort Study

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    We aimed to identify clinical factors associated with recurrent infective endocarditis (IE) episodes. The clinical characteristics of 2816 consecutive patients with definite IE (January 2008?2018) were compared according to the development of a second episode of IE. A total of 2152 out of 2282 (94.3%) patients, who were discharged alive and followed-up for at least the first year, presented a single episode of IE, whereas 130 patients (5.7%) presented a recurrence; 70 cases (53.8%) were due to other microorganisms (reinfection), and 60 cases (46.2%) were due to the same microorganism causing the first episode. Thirty-eight patients (29.2%), whose recurrence was due to the same microorganism, were diagnosed during the first 6 months of follow-up and were considered relapses. Relapses were associated with nosocomial endocarditis (OR: 2.67 (95% CI: 1.37?5.29)), enterococci (OR: 3.01 (95% CI: 1.51?6.01)), persistent bacteremia (OR: 2.37 (95% CI: 1.05?5.36)), and surgical treatment (OR: 0.23 (0.1?0.53)). On the other hand, episodes of reinfection were more common in patients with chronic liver disease (OR: 3.1 (95% CI: 1.65?5.83)) and prosthetic endocarditis (OR: 1.71 (95% CI: 1.04?2.82)). The clinical factors associated with reinfection and relapse in patients with IE appear to be different. A better understanding of these factors would allow the development of more effective therapeutic strategies

    The Spanish version of the reflective functioning questionnaire: Validity data in the general population and individuals with personality disorders

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    INTRODUCTION: Mentalization or reflective functioning (RF) is the capacity to interpret oneself or the others in terms of internal mental states. Its failures have been linked to several mental disorders and interventions improving RF have a therapeutic effect. Mentalizing capacity of the parents influences the children's attachment. The Reflective Functioning Questionnaire (RFQ-8) is a widely used tool for the assessment of RF. No instrument is available to assess general RF in Spanish-speaking samples. The aim of this study is to develop a Spanish version of the RFQ-8 and to evaluate its reliability and validity in the general population and in individuals with personality disorders. METHODS: 602 non-clinical and 41 personality disordered participants completed a Spanish translation of the RFQ and a battery of self-reported questionnaires assessing several RF related constructs (alexithymia, perspective taking, identity diffusion and mindfulness), psychopathology (general and specific) and interpersonal problems. Temporal stability was tested in a non-clinical sub-sample of 113 participants. RESULTS: Exploratory and confirmatory factor analyses suggested a one-factor structure in the Spanish version of the RFQ-8. RFQ-8 understood as a single scale was tested, with low scorings reflecting genuine mentalizing, and high scorings uncertainty. The questionnaire showed good internal consistence in both samples and moderate temporal stability in non-clinical sample. RFQ correlated significantly with identity diffusion, alexithymia, and general psychopathology in both samples; and with mindfulness, perspective taking, and interpersonal problems in clinical sample. Mean values of the scale were significantly higher in the clinical group. DISCUSSION: This study provides evidence that the Spanish version of the RFQ-8, understood as a single scale, has an adequate reliability and validity assessing failures in reflective functioning (i.e., hypomentalization) in general population and personality disorders
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