Develando el sindrome de Burnout en profesores de primero y segundo ciclo de Educacion General Basica de una escuela rural de la Zona Central de Chile

193 p.El estudio que a continuación se presenta es del tipo cualitativo, y tiene como objetivo aproximarnos a la comprensión del fenómeno de Burnout, sus causas, características y consecuencias, y sus complejas dimensiones en profesores de educación básica. Se busca develar el grado de ausencia o presencia del síndrome, identificando cual es el impacto que produce en el clima organizacional y fundamentalmente en el desempeño escolar de la organización. Para ello se construyó un marco teórico que nos permite introducirnos en la literatura para saber que nos aporta respecto de este tópico la psicología, sociología de la profesión y la teoría organizacional. Nuestro Chile vive ya desde hace algunos anos un proceso de reforma que tiene como finalidad mejorar la calidad de los aprendizajes de los educandos de todos los niveles, sabemos que en esto el rol del profesor es fundamental puesto que de el dependen los cambios verdaderos en el aula; por ello, pensamos que los profesores son el eje fundamental de la transformación de la sociedad, sociedad que demanden a estos permanentemente nuevos desafíos para producir los cambios requeridos. Estas políticas educativas llevan implícitas una serie de exigencias, que responden a las necesidades detectadas en la realidad de las comunidades, enfrentándose al aula en muchas oportunidades con grandes dificultades, como problemas sociales de los alumnos, escasez de material didáctico, indisciplina, bajo rendimiento, un clima organizacional deteriorado; sumándose todo esto a las bajas remuneraciones, todo lo cual va provocando en los docentes angustia, desencanto, frustración y desmotivación.En educación el riesgo psicológico esta muy presente por las diversas tensiones a que se encuentran sometidos los docentes, sean estas de tipo familiar, profesional o económicas, desencadenan un gran desgaste físico y psíquico, situación que nos ha motivado a realizar este estudio con el propósito de aproximarnos a la comprensión de este fenómeno: “Síndrome de Bornout” que puede afectar a muchos o pocos, pero puede tener múltiples consecuencias para la sociedad en su totalidad

Estratigrafía y estructura de los Andes Centrales Argentinos entre los 30º y 31º de Latitud Sur

In a cross-section through the Argentine central Andes, two large groups of rocks can be distinguished: a Gondwanic (F'aleozoic) basement, and an Andean cover. The basement is constituted by manne sedimentary units, intruded by Upper Paleozoic granitoid rocks. The most important Gondwanic structures, are East verging thrust and related folds. The Andean cover has a volcanic and volcanoclastic origin with some interbedded continental sedimentary rocks. The lower Permo-Tnassic unit (Choiyoi Group) is linked to an extensional tectonic event, and a Neogene sequence is connected to a compressional tectonic event that produced the inversion of the previous extensional features. The amount of Andean shortening calculated fiom cross sections is of about 10%. Most of the shortening in the Andean Cordillera was transferred to the Precordillera through the detachment fault. The up-lift of the Pampeanas area is linked with a new lower detachment fault

Efficiency Evaluation of Fully Integrated On-board EV Battery Chargers with Nine-Phase Machines

A fully integrated on-board battery charger for future electric vehicles (EVs) has been recently introduced. It re-utilizes all the propulsion components of an EV in charging/vehicle-to-grid (V2G) modes, it does not require any additional components or hardware reconfiguration, and charging/V2G modes are realized with zero electromagnetic torque production. Both fast (three-phase) and slow (single-phase) charging are possible, with unity power factor operation at the grid side. The solution is based on the use of a triple three-phase machine and a nine-phase inverter/rectifier. This paper reports on the results of efficiency evaluation for the said system. Testing is performed using both a nine-phase induction machine and a nine-phase permanent magnet (PM) machine for a range of operating conditions in charging/V2G modes, with both three-phase and single-phase grid connection. Additionally, the impact of converter interleaving on the losses and efficiency is also studied. Losses are separated for different subsystems, thus providing an insight into the importance of optimization of different EV power train components from the efficiency point of view. Promising efficiencies, in the order of 90%, are achieved although none of the system components have been optimized

Role of hydroxypropyl-β-cyclodextrin on freeze-dried and gamma-irradiated PLGA and PLGA–PEG diblock copolymer nanospheres for ophthalmic flurbiprofen delivery

Poly(D,L-lactide-co-glycolide) and poly(D,L-lactide-co-glycolide) with poly(ethylene glycol) nanospheres (NSs) incorporating flurbiprofen (FB) were freeze-dried with several cryoprotective agents and sterilized by γ-irradiation. Only when 5.0% (w/v) hydroxypropyl-β-cyclodextrin (HPβCD) was used, a complete resuspension by manual shaking and almost identical particle size of the NSs was obtained after freeze-drying. In vitro drug release and ex vivo corneal permeation of NSs with and without HPβCD were evaluated. The presence of HPβCD resulted in a reduction of burst effect, providing a more sustained release of the drug. A significant decrease in the FB transcorneal permeation of NSs containing HPβCD was obtained, related to the slower diffusion of FB observed in the in vitro results. The uptake mechanism of the NSs was examined by confocal microscopy, suggesting that NSs penetrate corneal epithelium through a transcellular pathway. Ocular tolerance was assessed in vitro and in vivo by the Eytex™ and Draize test, respectively. Long-term stability studies revealed that γ-irradiated NSs stored as freeze-dried powders maintained their initial characteristics. Stability studies of the resuspended NSs after 3 months of storage in the aqueous form showed that NSs were stable at 4°C, while formulations stored at 25°C and 40°C increased their initial particle size

An Integrated On-Board Battery Charger with a Nine-Phase PM Machine

A fully integrated on-board battery charger for electrical vehicles (EVs) has been developed recently using a nine-phase machine. All the components used for propulsion are employed in the charging process, no additional components are required, and there is no need for hardware reconfiguration between charging and propulsion modes of operation. The proposed solution can be connected directly to single-phase or three-phase grid to perform charging, so that the expensive off-board charger infrastructure is not needed. The only requirement is to use a nine-phase machine in combination with a nine-phase inverter in the powertrain of the EV. This however inevitably brings in further advantages in the propulsion mode, such as increased fault tolerance and the current subdivision into more phases. The benefits of the topology, originally developed for an induction machine, make it interesting for further investigation. Therefore, the performance of the charger is examined here using a permanent magnet synchronous machine (PMSM). The results show that the charger topology is applicable to other types of synchronous machines and is, even more importantly, independent of the angular spatial shift between the individual three-phase windings of the nine-phase machine’s stator. The results are comparable with those obtained using an induction machine and confirm the viability of the solution in conjunction with the PMSM as a propulsion motor

Gaze patterns hold key to unlocking successful search strategies and increasing polyp detection rate in colonoscopy

BACKGROUND:  The adenoma detection rate (ADR) is an important quality indicator in colonoscopy. The aim of this study was to evaluate the changes in visual gaze patterns (VGPs) with increasing polyp detection rate (PDR), a surrogate marker of ADR. METHODS:  18 endoscopists participated in the study. VGPs were measured using eye-tracking technology during the withdrawal phase of colonoscopy. VGPs were characterized using two analyses - screen and anatomy. Eye-tracking parameters were used to characterize performance, which was further substantiated using hidden Markov model (HMM) analysis. RESULTS:  Subjects with higher PDRs spent more time viewing the outer ring of the 3 × 3 grid for both analyses (screen-based: r = 0.56, P = 0.02; anatomy: r = 0.62, P < 0.01). Fixation distribution to the "bottom U" of the screen in screen-based analysis was positively correlated with PDR (r = 0.62, P = 0.01). HMM demarcated the VGPs into three PDR groups. CONCLUSION:  This study defined distinct VGPs that are associated with expert behavior. These data may allow introduction of visual gaze training within structured training programs, and have implications for adoption in higher-level assessment