504 research outputs found
Opinión de egresados en enfermería sobre la congruencia de los contenidos curriculares con los requerimientos laborales
ResumenLos perfiles profesionales de los egresados en área de la salud, y en particular de enfermería, requieren ajustarse a la compleja interacción que demandan las necesidades sociales y las exigencias del mercado laboral. Esto crea la necesidad de identificar fortalezas y debilidades durante su formación profesional a través de la sistematización de estudios de egresados, los cuales orientan a la mejora continua de los programas educativos, para facilitar la incorporación y desarrollo de los(as) egresados(as) en el ámbito laboral.ObjetivoDescribir la opinión de los egresados de enfermería de la Universidad Autónoma de Tlaxcala sobre la congruencia de los contenidos curriculares y requerimientos laborales al ofrecer el cuidado profesional.Material y métodosEstudio descriptivo, transversal. Incluyó 84 egresados de 3 generaciones, seleccionados por muestreo simple aleatorio. Se empleó un cuestionario adecuado y estructurado con base en la propuesta de la Asociación Nacional de Universidades e Instituciones de Educación Superior de 1998, organizado en 6 apartados.ResultadosEl 87% opinan que los contenidos curriculares son congruentes con las actividades que realizan al ofrecer el cuidado, el 86% perciben satisfacción de sus conocimientos, el 85% se consideran bien aceptados laboralmente, el 95% aprecian relevante su desempeño laboral, el 66% son contratados en 2.° y 3.er nivel de atención en el sector salud.ConclusionesLos egresados consideran que existe congruencia entre los contenidos curriculares con el desempeño profesional; se ubican mayormente en áreas asistenciales del 2.° y 3.er nivel de atención, y perciben satisfacción de los conocimientos adquiridos y aceptación laboral.AbstractProfessional profiles of graduates from the health areas, and particularly those from nursing, require adjustments in order to meet the complex interactions which social needs and labor market characteristics demand. This situation creates the need to identify strengths and weaknesses in the formation of these graduates. By systematizing and continuously improving their studies, a successful incorporation and development into the complex labor markets is more likely to be achieved.ObjectiveTo describe the opinion which the nursing graduates from the Tlaxcala Autonomous University have on the congruency of the curricular contents and the working requirements while providing professional care.Materials and methodsDescriptive and transversal study which included 84 graduates from 3 generations who were selected by random simple sampling, and which used a structured and convenient questionnaire following the 1998 ANUIES proposal organized in 6 dominions.Results87% of the participants opined the curricular contents are congruent with the activities they do while providing care; 86% perceive satisfaction with their knowledge; 85% consider they are well fit regarding labor; 95% consider their working performance relevant; 66% are hired into the Health Sector's 2nd and 3rd levels of attention.ConclusionsThere is congruency between the curricular contents and their professional performance; the graduates are mainly located within the assisting areas of the 2nd and 3rd levels of attention; they feel satisfied with their knowledge and perceive labor acceptance
Chemical conversion treatments to protect biodegradable magnesium in applications as temporary implants for bone repair
7 páginas, 7 figuras, 1 tabla.[ES] El presente estudio se desarrolló para mejorar la resistencia a la corrosión del magnesio puro, modificando su superficie mediante recubrimientos de conversión química. Se generaron capas de carbonato y fluoruro por inmersión en soluciones de NaHCO3 al 9 % y de HF al 48 %, respectivamente. La resistencia a la corrosión de las muestras con recubrimiento se evaluó en comparación con la del sustrato desnudo mediante técnicas electroquímicas en una solución fisiológica (PBS). Los resultados obtenidos han mostrado que el recubrimiento de carbonato no es capaz de proteger de la degradación al sustrato de magnesio. Por el contrario, el recubrimiento de fluoruro ha demostrado aumentar, significativamente, la resistencia a la corrosión del magnesio en medio fisiológico. La alta compacidad y adherencia al sustrato metálico de la capa de MgF2 generada mediante este sencillo tratamiento de conversión química confieren al recubrimiento buenas propiedades protectoras.[EN] The present study was developed to improve the corrosion resistance of pure magnesium by applying chemical
conversion coatings. Carbonate and fluoride layers were generated by immersion in solutions of NaHCO3 of
concentration 9 wt.%and HF of concentration 48 wt.%, respectively. Corrosion resistance of the coated samples was
evaluated in comparison with that of the uncoated substrate by electrochemical techniques in a physiological solution
(PBS). Results have shown that the carbonate coating is not viable to be used for protecting magnesium against
corrosion.On the contrary, the fluoridemagnesiumcoating significantly increases the corrosion resistance ofmagnesium
in physiological medium. The high compactness and adherence to the base metal of theMgF2 layer produced by this
simple chemical conversion treatment confer the protective properties to the coating.Los autores agradecen al MEC la financiación del
proyecto con referencia MAT 2008-06719-C03-01.
M. Carboneras agradece al CSIC la concesión de un
contrato JAE-Doc.Peer reviewe
Phase diagram of Fe-doped Ni-Mn-Ga ferromagnetic shape-memory alloys
We have studied the effect of Fe addition on the structural and magnetic
transitions in the magnetic shape memory alloy Ni-Mn-Ga by substituting
systematically each atomic species by Fe. Calorimetric and AC susceptibility
measurements have been carried out in order to study the magnetic and
structural transformation properties. We find that the addition of Fe modifies
the structural and magnetic transformation temperatures. Magnetic transition
temperatures are displaced to higher values when Fe is substituted into
Ni-Mn-Ga, while martensitic and premartensitic transformation temperatures
shift to lower values. Moreover, it has been found that the electron per atom
concentration essentially governs the phase stability in the quaternary system.
However, the observed scaling of transition temperatures with differs
from that reported in the related ternary system Ni-Mn-Ga.Comment: 8 pages, 8 figures. Accepted for publication in the Physical Review
Linking changes in radial profiles of sap flux density with the response of water vapour exchange to water deficit
8 páginas, 5 figuras, 1 tabla, 19 referencias.-- IX International Workshop on Sap Flow, celebrado del 4-7 de junio 2013, en Gante, Bélgica.Knowledge of temporal variations in radial profiles of sap flux density (Js) and its relation to canopy water vapour exchange would help to improve our understanding of plant water relations. In this study we aimed to test if there is a consistent radial profile of Js in olive trees under optimal soil water availability and severe water stress conditions. Furthermore, if the radial profile of Js is not consistent through time we aimed to assess whether this radial variability can be explained through differential water exchange response to evaporative demand (D) of sun-exposed, new foliage and shade, old foliage. We measured sap flux density in the trunk of 6-year-old olive trees under two different irrigation treatments: a full irrigation treatment and a treatment replacing 30% of the of irrigation needs. We related the hourly radial profiles characterized with the Beta probability distribution function with independent water vapour exchange measurements at different exposures in the tree canopy (sun-exposed, young foliage and shade, old foliage). Results showed that under well irrigated conditions the shape of the radial profile of Js hardly varied, but under water deficit situations most of the sap appears to be conducted deeper into the sapwood and Js is also more variable throughout the sapwood. Accordingly, results demonstrated that in shade, old foliage water vapour exchange varied less than in sun-exposed new foliage. As a result, in days under severe water deficit, the contribution of shade old foliage to the whole tree transpiration was greater. Radial profile changes and canopy measurements were found to respond in a similar way to D. During conditions of low D and soil water deficit it was observed a greater contribution of the inner xylem to total stem flow and shade, old leaves to canopy gas exchange.Peer reviewe
Synthesis of Nylon 6/Modified Carbon Black Nanocomposites for Application in Uric Acid Adsorption
High uric acid levels cause different clinic conditions. One of them is hyperuricemia, which leads to kidney damage. A solution for eliminating uric acid in the blood is by hemodialysis, which is performed using nanocomposite membranes. In this work, Nylon 6 nanocomposites were synthesized with modified carbon black (MCB), which were considered candidate materials for hemodialysis membranes. The modification of carbon black was made with citric acid using the variable-frequency ultrasound method. The new MCB was characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), transmission electron microscopy (TEM), and dispersion tests. Nylon 6/MCB nanocomposites were processed using the ultrasound-assisted melt-extrusion method to improve the dispersion procedure of the nanoparticles. The Nylon 6/MCB nanocomposites were characterized by FTIR, TGA, and differential scanning calorimetry (DSC). These were assessed for the absorption of toxins and hemocompatibility. MBC and nanocomposites showed excellent uric acid removal (78–82%) and hemocompatibility (1.6–1.8%). These results suggest that Nylon 6/MCB nanocomposites with low loading percentages can be used on a large scale without compatibility problems with blood
Efecto de la fertilización con fósforo sobre el rendimiento y la absorción de nutrimientos de la papa en andisol de Juan Viñas, Costa Rica
Se estudió la respuesta del cultivo de la papa a la fertilización fosfórica en un suelo Hydric Hapludands de la Hacienda Juan Viñas. Se aplicaron 0, 150, 300, 450 y 600 kg.ha-1 de P2O5 por 1 y 2 años consecutivos. Se tomaron muestras foliares al momento de floración (48 dds), de biomasa aérea antes de la quema de follaje (93 dds) y de tubérculos al momento de la cosecha (116 dds). A las muestras de tejidos se les midió el peso fresco y seco y se les realizó el análisis químico para N, P, Ca, Mg, K, Mn, Zn, Cu, Fe, S y B. Al aplicar P únicamente el primer año del experimento, el rendimiento del cultivo fue inferior y no se apreció ningún efecto residual con ninguna de las dosis. Con la aplicación consecutiva de P durante 2 años, el cultivo respondió de forma creciente al aumento en la dosis de fertilizante alcanzándose el máximo rendimiento de tubérculos (16,39 t.ha-1) con 600 kg.ha-1 de P2O5. La variación de nutrimentos en los tejidos no se vio afectada por la adición de P. Los nutrimentos móviles (NPK) se redistribuyeron en mayor porcentaje a los tubérculos en un 27-65%, seguidos por los de movilidad variable Cu, Mg y Zn, en un 14-38% y por último el Ca, Mn y Fe que apenas se extrajeron/redistribuyeron en un 2-6%. Para obtener un efecto residual importante de P en el suelo, fue necesario aplicar 450 kg.ha-1 de P2O5 por 2 años consecutivos. Se sugiere que para obtener un adecuado rendimiento de tubérculos en este Andisol es necesaria la aplicación de P en cada ciclo
Efecto residual del fertilizante fosfatado adicionado al cultivo de la papa en un andisol de Juan Viñas, Costa Rica
Se estudió el efecto residual de la aplicación de P como fertilizante al cultivo de la papa en un suelo Hydric Hapludands de la Hacienda Juan Viñas, aplicando 0, 150, 300, 450 y 600 kg.ha-1 de P2O5 por 1 y 2 años consecutivos. Se tomaron muestras de suelo al inicio y final del cultivo, foliares al momento de floración (48 dds), de biomasa aérea antes de la quema de follaje (93 dds) y de tubérculos al momento de la cosecha (116 dds). A las muestras de suelo se les determinó el P disponible mediante los métodos de Olsen modificado, Bray 1 y Mehlich 3. Al aplicar P durante el primer año del experimento, el rendimiento fue bajo y no se apreció efecto residual con ninguna de las dosis. Con la aplicación consecutiva de P durante 2 años, el cultivo respondió de forma creciente al aumento en la dosis de fertilizante alcanzándose el máximo rendimiento de tubérculos (16,39 t.ha-1) con la cantidad de 600 kg.ha-1 de P2O5. El método de Olsen modificado se consideró como el mejor para estimar el P disponible en el suelo, ya que fue el que mejor representó la tendencia de este nutrimento durante los 2 años de estudio. Para obtener un efecto residual importante fue necesaria al menos, la dosis de 450 kg.ha-1 de P2O5, aplicada por 2 años consecutivos, con la que se consiguió un aumento de 2-3 mg.l-1.año-1 de P. La retención de P por parte del suelo fue del 93% durante el primer cultivo y del 91% durante el segundo. El mejor valor de correlación entre las distintas soluciones extractoras se consiguió con Olsen modificado y Mehlich 3 (R2=0,705)
Photon Shielding Features of Quarry Tuff
Abstract. Cantera is a quarry tuff widely used in the building industry; in this work the shielding features of cantera were determined. The shielding characteristics were calculated using XCOM and MCNP5 codes for 0.03, 0.07, 0.1, 0.3, 0.662, 1, 2, and 3 MeV photons. With XCOM the mass interaction coefficients, and the total mass attenuation coefficients, were calculated. With the MCNP5 code a transmission experiment was modelled using a point-like source located 42 cm apart from a point-like detector. Between the source and the detector, cantera pieces with different thickness, ranging from 0 to 40 cm were included. The collided and uncollided photon fluence, the Kerma in air and the Ambient dose equivalent were estimated. With the uncollided fluence the linear attenuation coefficients were determined and compared with those calculated with XCOM. The linear attenuation coefficient for 0.662 MeV photons was compared with the coefficient measured with a NaI(Tl)-based �-ray spectrometer and a 137Cs source
Olive classification according to external damage using image analysis.
The external appearance of an olive’s skin is the most decisive factor in determining its
quality as a fruit. This work tries to establish a hierarchical model based on the features
extracted from images of olives reflecting their external defects. Seven commercial
categories of olives, established by product experts, were used: undamaged olives,
mussel-scale or ‘serpeta’, hail-damaged or ‘granizo’, mill or ‘rehús’, wrinkled olive or
‘agostado’, purple olive and undefined-damage or ‘molestado’. The original images
were processed using segmentation, colour parameters and morphological features of
the defects and the whole fruits. The application of three consecutive discriminant
analyses resulted in the correct classification of 97% and 75% of olives during
calibration and validation, respectively. However the correct classification percentages
vary greatly depending on the categories, ranging 80–100% during calibration and 38–
100% during validation
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