451 research outputs found

    Estimacion de la hojarasca acumulada bajo Eucaliptus globulus y Nothofagus obliqua en una plantacion forestal y en un bosque nativo, ubicados en la precordillera andina de la VII Region

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    77 p.En una Plantación Forestal y un Bosque Nativo, ubicados en el Predio EL Picazo, en la Precordillera Andina de la VII Región del Maule, se realizo una estimación y comparación de la cantidad y variación espacial de la hojarasca y hojarasca descompuesta, acumuladas bajo Eucaliptus globlulus y Nothofagus obliqua. A tal fin, se cosechó la hojarasca acumulada dentro de un cuadrante de 20*20 cm., mediante un muestreo anidado alrededor de cinco individuos para cada situación. El material fue secado a 60°C, hasta peso constante y posteriormente pesado. Se utilizó un diseño multifactorial de factores fijos (distancia, exposición y árbol) para analizar las variables cuantitativas medidas. Eucaliptus globulus aportó 395 gr/m2 de hojarasca y 1.730 gr/m2 de hojarasca descompuesta, mientras que debajo de Nothofagus obliqua se acumulo 335 gr/m2 de hojarasca y 1.632 gr/m2 de hojarasca descompuesta. Mientras que en Eucaliptus globulus solo los factores exposición y árbol influenciaron la acumulación de hojarasca descompuesta, en Nothofagus obliqua la distancia al fuste, la exposición y el árbol influenciaron significativamente la acumulación de hojarasca descompuesta. También se encontró influencia significativa del factor exposición y árbol en el compartimiento de hojarasca para Nothofagus obliqua

    Vida y milagros de la bienaventurada santa Catherina de Sena

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    Sign.: A6, B-Q8Autor tomado de h. IXMarca tip. en el v. de la última h.ColofónPort. grab. xil. y a dos tintasGrab. xil., a toda plana, y a dos tintas en A6 v.Errores de fol. Delante de la primera h. numerada (la IX) solo hay seis h.Texto a dos col.Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-201

    Effects in short and long term of global postural reeducation (GPR) on chronic low back pain: A controlled study with one-year follow-up

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    Objective. Comparing global postural reeducation (GPR) to a standard physiotherapy treatment (PT) based on active exercises, stretching, and massaging for improving pain and function in chronic low back pain (CLBP) patients. Design. Prospective controlled study. Setting. Outpatient rehabilitation facility. Participants. Adult patients with diagnosis of nonspecific, chronic (>6 months) low back pain. Interventions. Both treatments consisted of 15 sessions of one hour each, twice a week including patient education. Measures. Roland Morris Disability Questionnaire to evaluate disability, and Numeric Analog Scale for pain. A score change >30% was considered clinically significant. Past treatments, use of medications, smoking habits, height, weight, profession, and physical activity were also recorded on baseline, on discharge, and 1 year after discharge (resp., T0, T1, and T2). Results. At T0 103 patients with cLBP (51 cases and 52 controls) were recruited. The treatment (T1) has been completed by 79 (T1) of which 60 then carried out the 1-year follow-up (T2). Both GPR and PT at T1 were associated with a significant statistical and clinical improvement in pain and function, compared to T0. At T2, only pain in GPR still registered a statistically significant improvement

    Validación Psicométrica del Motivated Strategies for Learning Questionnaire en Universitarios Mexicanos

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    Introduction. The Motivated Strategies for Learning Questionnaire (MSLQ) is a self-report instrument designed to assess students' motivation and learning strategies (cognitive, meta-cognitive, and resource management). In the present study, we focused on translate, adapt and validate the MSLQ to Mexican educational context. Method. The original version of the MSLQ was translated and adapted to mexican education-al context under the name of Cuestionario de Motivación y Estrategias de Aprendizaje (CMEA) taking into account 22 guidelines established by the International Test Commission (ITC) and subsequently administered to mexican students (N=1,140) of a southeastern univer-sity of México. Results. Results allow concluding that the items were grouped in each of the factors using factorization of major axes. Internal consistency rates obtained were acceptable. Discussion and conclusion. The results show great power providing useful information about how this instrument can answer our initial question of self-regulated learning: How do stu-dents can become experts in their own learning processes? Keywords: MSLQ, psychometric properties, self-regulated learning, university students

    Poeta y suegra en guerra : comedia en tres actos y en verso

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    Representado con aplauso en el Teatro de Novedades, el día 1 de diciembre de 1859Dedicado por el autor a Fernando Fernández de San RománCopia digital. Madrid : Ministerio de Cultura. Dirección General del Libro, Archivos y Bibliotecas, 2010Pie de imprenta tomado del colofónSign.:1-3(4º)Texto a dos col.Colección de comedias representadas con éxito en los Teatros de la Cort

    El abencerraje y la hermosa Jarifa

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    ColofónMarca tip. en portEsc. real xil. en h. posterior a la por

    Intracellular Triggering of Fas Aggregation and Recruitment of Apoptotic Molecules into Fas-enriched Rafts in Selective Tumor Cell Apoptosis

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    We have discovered a new and specific cell-killing mechanism mediated by the selective uptake of the antitumor drug 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (ET-18-OCH3, Edelfosine) into lipid rafts of tumor cells, followed by its coaggregation with Fas death receptor (also known as APO-1 or CD95) and recruitment of apoptotic molecules into Fas-enriched rafts. Drug sensitivity was dependent on drug uptake and Fas expression, regardless of the presence of other major death receptors, such as tumor necrosis factor (TNF) receptor 1 or TNF-related apoptosis-inducing ligand R2/DR5 in the target cell. Drug microinjection experiments in Fas-deficient and Fas-transfected cells unable to incorporate exogenous ET-18-OCH3 demonstrated that Fas was intracellularly activated. Partial deletion of the Fas intracellular domain prevented apoptosis. Unlike normal lymphocytes, leukemic T cells incorporated ET-18-OCH3 into rafts coaggregating with Fas and underwent apoptosis. Fas-associated death domain protein, procaspase-8, procaspase-10, c-Jun amino-terminal kinase, and Bid were recruited into rafts, linking Fas and mitochondrial signaling routes. Clustering of rafts was necessary but not sufficient for ET-18-OCH3–mediated cell death, with Fas being required as the apoptosis trigger. ET-18-OCH3–mediated apoptosis did not require sphingomyelinase activation. Normal cells, including human and rat hepatocytes, did not incorporate ET-18-OCH3 and were spared. This mechanism represents the first selective activation of Fas in tumor cells. Our data set a framework for the development of more targeted therapies leading to intracellular Fas activation and recruitment of downstream signaling molecules into Fas-enriched rafts

    Description of Main Innovative and Alternative Methodologies for Mathematical Learning of Written Algorithms in Primary Education

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    The traditional way of teaching mathematics generates significant learning difficulties in students that are reflected in their academic performance. In recent years, the number of teachers and researchers interested in finding innovative, flexible and comprehensible methodologies has increased. The main objective of this article has been to carry out a theoretical review of the methodologies for learning/teaching mathematics at school level. Central elements of international and national method initiatives have been highlighted. The empirical evidence on the Singapore method and the Algorithm Based on Numbers (ABN) method confirms the need to include innovative and manipulative strategies in the classroom. The Singapore method has been shown as a source that improves students ' problem solving skill, mathematical competence, boosting reasoning, and a higher motivation. Some studies focused on the effectiveness of the ABN method and its influence on mathematical cognition. The use of this methodology and learning in flipped classroom have obtained significant results in teacher training. These results could provide guidance about how to improve pre-service education in Primary Bachelor's Degree. The findings presented in the manuscript could be a basis for opening new lines of quantitative research, with the aim of analysing problem solving and the use of manipulative materials in mathematics. Thus, future research should focus on analysing the cognitive processes involved in mathematical learning, carrying out empirical studies in schools. In addition, it is necessary to improve future teachers' training, so that they can learn about new alternatives for mathematical teaching and the available resources to be able to put it into practice. Moreover, alternative methodologies are a necessary driver for the improvement of mathematical performance both inside and outside the classroom, and also for the technological and economic development of countries

    Development and Long-Term Follow-Up of an Experimental Model of Myocardial Infarction in Rabbits

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    [EN] A chronic model of acute myocardial infarction was developed to study the mechanisms involved in adverse postinfarction ventricular remodeling. In an acute myocardial infarction (AMI), the left circumflex coronary artery of New Zealand White rabbits (n = 9) was occluded by ligature for 1 h, followed by reperfusion. A specific care protocol was applied before, during, and after the intervention, and the results were compared with those of a sham operated group (n = 7). After 5 weeks, programmed stimulation and high-resolution mapping were performed on isolated and perfused hearts using the Langendorff technique. The infarct size determined by 2,3,5-triphenyltetrazolium chloride inside of the area at risk (thioflavin-S) was then determined. The area at risk was similar in both groups (54.33% (experimental infarct group) vs. 58.59% (sham group), ns). The infarct size was 73.16% as a percentage of the risk area. The experimental infarct group had a higher inducibility of ventricular arrhythmias (100% vs. 43% in the sham group, p = 0.009). A reproducible chronic experimental model of myocardial infarction is presented in which the extent and characteristics of the lesions enable the study of the vulnerability to develop ventricular arrhythmias because of the remodeling process that occurs during cardiac tissue repair.This research was funded by Generalitat Valenciana (PROMETEO/2018/078), Instituto de Salud Carlos III (CB16/11/00486; PI15/01408; PIE15/0001 3and PI18/01620) to F.J.C.Genovés, P.; Arias-Mutis, ÓJ.; Parra, G.; Such-Miquel, L.; Zarzoso, M.; Del Canto, I.; Soler, C.... (2020). Development and Long-Term Follow-Up of an Experimental Model of Myocardial Infarction in Rabbits. Animals. 10(9). https://doi.org/10.3390/ani1009157610

    Effect of chronic exercise on myocardial electrophysiological heterogeneity and stability. Role of intrinsic cholinergic neurons: A study in the isolated rabbit heart

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    [EN] A study has been made of the effect of chronic exercise on myocardial electrophysiological heterogeneity and stability, as well as of the role of cholinergic neurons in these changes. Determinations in hearts from untrained and trained rabbits on a treadmill were performed. The hearts were isolated and perfused. A pacing electrode and a recording multielectrode were located in the left ventricle. The parameters determined during induced VF, before and after atropine (1 mu M), were: fibrillatory cycle length (VV), ventricular functional refractory period (FRPVF), normalized energy (NE) of the fibrillatory signal and its coefficient of variation (CV), and electrical ventricular activation complexity, as an approach to myocardial heterogeneity and stability. The VV interval was longer in the trained group than in the control group both prior to atropine (78 +/- 10 vs. 68 +/- 10 ms) and after atropine (76 +/- 8 vs. 67 +/- 10 ms). Likewise, FRPVF was longer in the trained group than in the control group both prior to and after atropine (53 +/- 8 vs. 42 +/- 7 ms and 50 +/- 6 vs. 40 +/- 6 ms, respectively), and atropine did not modify FRPVF. The CV of FRPVF was lower in the trained group than in the control group prior to atropine (12.5 +/- 1.5% vs. 15.1 +/- 3.8%) and, decreased after atropine (15.1 +/- 3.8% vs. 12.2 +/- 2.4%) in the control group. The trained group showed higher NE values before (0.40 +/- 0.04 vs. 0.36 +/- 0.05) and after atropine (0.37 +/- 0.04 vs. 0.34 +/- 0.06; p = 0.08). Training decreased the CV of NE both before (23.3 +/- 2% vs. 25.2 +/- 4%; p = 0.08) and after parasympathetic blockade (22.6 +/- 1% vs. 26.1 +/- 5%). Cholinergic blockade did not modify these parameters within the control and trained groups. Activation complexity was lower in the trained than in the control animals before atropine (34 +/- 8 vs. 41 +/- 5), and increased after atropine in the control group (41 +/- 5 vs. 48 +/- 9, respectively). Thus, training decreases the intrinsic heterogeneity of the myocardium, increases electrophysiological stability, and prevents some modifications due to muscarinic block.This research was supported by the Spanish Ministry of Education and Science, (DEP2007-73234-C03-01 to AMA), http://www.mecd.gob.es/portada-mecd/; and the Generalitat Valenciana (PROMETEO 2010/093 to FJC, and FPI/2008/003 to MZ), http://www.gva.es/va/inicio/presentacion; jsessionid=ydprbDQZTsCTz85W1Such-Miquel, L.; Brines-Ferrando, L.; Alberola, A.; Zarzoso Muñoz, M.; Chorro Gasco, FJ.; Guerrero-Martínez, JF.; Parra-Giraldo, G.... (2018). Effect of chronic exercise on myocardial electrophysiological heterogeneity and stability. Role of intrinsic cholinergic neurons: A study in the isolated rabbit heart. 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