204 research outputs found
Las rondas como estrategia metodológica en el proceso de enseñanza-aprendizaje
Tesis (Educación Parvularia, Licenciado en Educación)Como educadores se debe estar en una permanente búsqueda de recursos, estrategias y herramientas que permitan al educando ser activo y protagonista de su propio aprendizaje.
Desde la antigüedad, el niño(a) de manera natural, utiliza el juego y el movimiento de su propio cuerpo para adquirir nuevos conocimientos; y se ha comprobado a su vez, la música incide favorablemente en la adquisición de aprendizajes. Por lo tanto, es necesario encontrar e implementar una actividad que reúna estos tres factores.
Es por esto que surge la idea de implementar la utilización de las rondas infantiles, cómo estrategia metodológica para favorecer el proceso de enseñanza-aprendizaje.
Esta investigación se basa en diversas teorías sobre los factores que componen las rondas infantiles (juego, movimiento y música).
El estudio empírico de la investigación tiene un enfoque de tipo exploratorio descriptivo, con un diseño experimental de comparación con un grupo estático, basado en los métodos cuantitativos y cualitativos (método mixto). Los datos se adquirieron a través de la aplicación de una escala de apreciación en el nivel Pre-Kínder C del Colegio Parroquial Santa Rosa de la Comuna de Lo Barnechea, donde se midió la incidencia de las rondas infantiles en la adquisición de aprendizajes, esto mediante una evaluación post-test. Para esto, se realiza una propuesta de actividades para ser aplicadas en el aula.
De acuerdo a los análisis de datos obtenidos, no se pudo comprobar que las rondas infantiles aplicadas como estrategia de enseñanza, hayan sido responsables de los resultados de la intervención, dado que pueden haber influido una serie de factores que serán detallados en la investigación
Note: Stacked rings for terahertz wave-guiding
We demonstrate the construction of corrugated waveguides using stacked rings to propagate terahertz frequencies. The waveguide allows propagation of the same fundamental mode as an optical-fiber, namely, the HE11 mode. This simple concept opens the way for corrugated wave-guides up to several terahertz, maintaining beam characteristics as for terahertz applications. (C) 2011 American Institute of Physics. [doi:10.1063/1.3597579
Stacked rings for terahertz wave-guiding
We demonstrate the construction of corrugated waveguides using stacked rings to propagate terahertz frequencies. The waveguide allows propagation of the same fundamental mode as an optical-fiber, namely, the H E11 mode. This simple concept opens the way for corrugated wave-guides up to several terahertz, maintaining beam characteristics as for terahertz applications
Early onset lactating adenoma and the role of breast MRI: a case report
<p>Abstract</p> <p>Introduction</p> <p>Lactating adenoma is a benign condition, representing the most prevalent breast lesion in pregnant women and during puerperium; in this paper, a case of a woman with lactating adenoma occurring during the first trimester of pregnancy is reported. There have been no reports in the literature, according to our search, focusing on magnetic resonance imaging findings in cases of lactating adenomas. Also the early onset of the lesion during the first trimester of pregnancy is quite unusual and possibly unique.</p> <p>Case presentation</p> <p>We report the case of a primiparous 30-year-old Caucasian woman, who noted an asymptomatic lump within her left breast during the 9<sup>th </sup>week of gestation, slightly increasing in size over the next few weeks. Ultrasound demonstrated a hypoecoic solid mass, hypervascularized and measuring 4 cm. On magnetic resonance imaging, performed in the first month after delivery, the lesion appeared as an ovoidal homogeneous mass, with regular margins and a significant contrast enhancement indicative of a giant adenoma.</p> <p>Conclusion</p> <p>Magnetic resonance imaging could play an important role in the differential diagnosis of pregnancy-related breast lumps, particularly during puerperium, thus avoiding unnecessary surgical biopsies.</p
Experimental study from linear to chaotic regimes on a terahertz-frequency gyrotron oscillator
Basic wave-particle interaction dynamics from linear to chaotic regimes is experimentally studied on a frequency tunable gyrotron generating THz radiation in continuous mode (200W) at 263GHz which will be used for dynamic nuclear polarization nuclear magnetic resonance spectroscopy applications. In the studied system, the nonlinear dynamics associated to the waveparticle interaction is dominated by longitudinal mode competition of a given transverse TEm;p cavity-mode. This study covers a wide range of control parameter from gyro-traveling wave tube (gyro-TWT) to gyro-backward wave oscillator (gyro-BWO) like interactions for which extensive theoretical studies have been performed in the past on a simplified system. Besides the common route to chaos characterized by period doubling, other routes have been identified among which some are characterized by line-width frequency-broadening on the side-bands. The complex nonlinear dynamics is in good agreement with the theory and the experimental results are discussed on the basis of the prediction obtained with the nonlinear time-dependent selfconsistent codes TWANG and EURIDICE both based on a slow-time scale formulation of the self-consistent equations governing the wave-particle dynamics. V
A novel potent Fas agonist for selective depletion of tumor cells in hematopoietic transplants
There remains a clear need for effective tumor cell purging in autologous stem cell transplantation (ASCT) where residual malignant cells within the autograft contribute to disease relapse. Here we propose the use of a novel Fas agonist with potent pro-apoptotic activity, termed MegaFasL, as an effective ex-vivo purging agent. MegaFasL selectively kills hematological cancer cells from lymphomas and leukemias and prevents tumor development at concentrations that do not reduce the functional capacity of human hematopoietic stem/progenitor cells both in in vitro and in in vivo transplantation models. These findings highlight the potential use of MegaFasL as an ex-vivo purging agent in ASCT
Double blind, randomized, placebo controlled clinical trial for the treatment of diabetic foot ulcers, using a nitric oxide releasing patch: PATHON
<p>Abstract</p> <p>Background</p> <p>Diabetes Mellitus constitutes one of the most important public health problems due to its high prevalence and enormous social and economic consequences. Diabetic foot ulcers are one of the chronic complications of diabetes mellitus and constitute the most important cause of non-traumatic amputation of inferior limbs. It is estimated that 15% of the diabetic population will develop an ulcer sometime in their lives. Although novel therapies have been proposed, there is no effective treatment for this pathology. Naturally produced nitric oxide participates in the wound healing process by stimulating the synthesis of collagen, triggering the release of chemotactic cytokines, increasing blood vessels permeability, promoting angiogenic activity, stimulating the release of epidermical growth factors, and by interfering with the bacterial mitochondrial respiratory chain. Topically administered nitric oxide has demonstrated to be effective and safe for the treatment of chronic ulcers secondary to cutaneous leishmaniasis. However, due to their unstable nitric oxide release, the topical donors needed to be applied frequently, diminishing the adherence to the treatment. This difficulty has led to the development of a multilayer polymeric transdermal patch produced by electrospinning technique that guarantees a constant nitric oxide release. The main objective of this study is to evaluate the effectiveness and safety of this novel nitric oxide releasing wound dressing for the treatment of diabetic foot ulcers.</p> <p>Methods and design</p> <p>A double-blind, placebo-controlled clinical trial, including 100 diabetic patients was designed. At the time of enrollment, a complete medical evaluation and laboratory tests will be performed, and those patients who meet the inclusion criteria randomly assigned to one of two groups. Over the course of 90 days group 1 will receive active patches and group 2 placebo patches. The patients will be seen by the research group at least every two weeks until the healing of the ulcer or the end of the treatment. During each visit the healing process of the ulcer, the patient's health status and the presence of adverse events will be assessed. Should the effectiveness of the patches be demonstrated an alternative treatment would then be available to patients.</p> <p>Trial registration</p> <p>NCT00428727.</p
Precancerous Stem Cells Have the Potential for both Benign and Malignant Differentiation
Cancer stem cells (CSCs) have been identified in hematopoietic and solid tumors. However, their precursors—namely, precancerous stem cells (pCSCs) —have not been characterized. Here we experimentally define the pCSCs that have the potential for both benign and malignant differentiation, depending on environmental cues. While clonal pCSCs can develop into various types of tissue cells in immunocompetent mice without developing into cancer, they often develop, however, into leukemic or solid cancers composed of various types of cancer cells in immunodeficient mice. The progress of the pCSCs to cancers is associated with the up-regulation of c-kit and Sca-1, as well as with lineage markers. Mechanistically, the pCSCs are regulated by the PIWI/AGO family gene called piwil2. Our results provide clear evidence that a single clone of pCSCs has the potential for both benign and malignant differentiation, depending on the environmental cues. We anticipate pCSCs to be a novel target for the early detection, prevention, and therapy of cancers
Langmuir probe electronics upgrade on the tokamak a configuration variable
A detailed description of the Langmuir probe electronics upgrade for TCV (Tokamak a Configuration Variable) is presented. The number of amplifiers and corresponding electronics has been increased from 48 to 120 in order to simultaneously connect all of the 114 Langmuir probes currently mounted in the TCV divertor and main-wall tiles. Another set of 108 amplifiers is ready to be installed in order to connect 80 new probes, built in the frame of the TCV divertor upgrade. Technical details of the amplifier circuitry are discussed as well as improvements over the first generation of amplifiers developed at SPC (formerly CRPP) in 1993/1994 and over the second generation developed in 2012/2013. While the new amplifiers have been operated successfully for over a year, it was found that their silicon power transistors can be damaged during some off-normal plasma events. Possible solutions are discussed. (C) 2019 Author(s)
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