225 research outputs found

    El estado actual de la investigación sobre la congruencia persona-ambiente. Propuesta de aplicación de un diseño experimental

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    En el presente trabajo se hace una revisión del estado actual de la investigación sobre la congruencia persona-ambiente, analizando los principales problemas conceptuales y metodológicos que existen en esta línea de investigación, así como las críticas que recibe uno de los modelos más representativos del momento: el modelo de la elección vocacional de Holland. Según este autor, los individuos suelen elegir profesiones que son congruentes con sus características personales, y este ajuste tiene repercusiones positivas tanto para el rendimiento como para la satisfacción en el trabajo. Además, existen otros modelos que han sido propuestos desde diferentes perspectivas (el estrés laboral, socialización laboral, ajuste laboral...). Teniendo en cuenta los inconvenientes que presentan la mayoría de los estudios empíricos realizados, se plantea la posibilidad de abordar el tema desde el paradigma experimental sugiriendo un diseño que permite solventar, o al menos minimizar, dichos problemas.The aim of this paper is to review the present state of the person-environment congruence research. We analyze the main conceptual and methodological problems that this research have and the cristicisms that one of the most representative model receives: Holland’s vocational choices model. This author suggests that the individuals tend to choose occupations that are congruent with their personal characteristics, and that this fi t (or adjustment) has positive implications both for the performance and job satisfaction. On the other hand, models from other approaches have also been proposed (work stress, work socialization, laboral fi t (or adjustment...). Taking into account the inconvenients that most of these kind of studies have, the possibility of start on this subject from an experimental paradigm suggesting a design that may solve or reduce these problems is proposed

    Rapid Determination of Olive Oil Chlorophylls and Carotenoids by Using Visible Spectroscopy

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    The determination of total chlorophylls and total carotenoids in olive oil by using visible spectroscopy (VIS) is reported. The proposed technique has been compared with the determination of these pigments by near infrared spectroscopy (NIRS) and VIS together with NIRS. Several procedures for multivariate regression were tested. The reference methods used were the determination of the extinction coefficient K670 for total chlorophylls and K470 for total carotenoids. A total of 258 samples were tested. The optimization of the calibration for total chlorophylls was set by using multiple linear regression (MLR) from the wavelengths 670¿686 nm exclusively visible. Its satisfactory performance was proven from the model coefficients standard error of calibration SEC 2.63 and R2 0.97, and the residual predictive deviation (RPD) 5.76 from the external validation. For the total carotenoids the best VIS calibration was fit by using the window of 465¿475 nm and partial least squares (PLS), which provided an RPD of 3.68. However, the model built using the entire spectrum VIS-NIRS available (350¿2,500 nm) was slightly better for this last pigment, showing an RPD of 3.86. Hence, this study showed that the proposed VIS technique can be advantageous for the determination of total chlorophylls in olive oils while it is also suitable for determining total carotenoids.The authors are indebted to the Junta de Andalucía (project AGR-6456) for its financial support, and gratefully acknowledge Antonio Montero, of the Instituto de Recursos Naturales y Agrobiología (CSIC) for his technical assistance. Our thanks are also due to the group Quality and Purity of Oils, of the Instituto de la Grasa (CSIC), for the use of the chromatographic equipmentPeer Reviewe

    Evaluation of the Inclusion of the Green Seaweed Ulva ohnoi as an Ingredient in Feeds for Gilthead Sea Bream (Sparus aurata) and European Sea Bass (Dicentrarchus labrax)

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    Simple Summary The use of seaweeds in aquafeeds is receiving increasing attention due to their potential nutritional and functional benefits. However, several green seaweeds such as Ulva presents nutritional limitations because of the undigestible polysaccharides, although these may exert a positive effect on the immunological status of the fish. The present study developed three different experiments aimed to re-evaluate the presence of protease inhibitors described for Ulva ohnoi, to assess its nutritional value as an ingredient and also to evaluate its potential protective effect on the oxidative metabolism of fish, being experiments developed in two different fish species (European sea bass Dicentrarchus labrax and gilthead sea bream, Sparus aurata). Results indicate the absence of negative effects of U. ohnoi on protein digestion of sea bream but a limited value as a feed ingredient. In contrast, its contents in bioactives seem to be correlated to the observed positive effects on the immune status and oxidative metabolism when fish are challenged by the consumption of highly oxidized dietary oil. This study evaluated the use of Ulva ohnoi as an ingredient in feeds for aquaculture in three different experiments. Experiment 1 was oriented to confirm the negative effect of U. ohnoi on fish digestion. Experiment 2 assessed the effect on growth, feed efficiency, and immune status of juvenile sea bass (Dicentrarchus labrax) fed on diets including U. ohnoi, previously treated or not with carbohydrases used to partially hydrolyze indigestible polysaccharides. Experiment 3 was aimed to evaluate the potential protective effect of U. ohnoi on the oxidative status of sea bream (Sparus aurata) challenged by the consumption of a feed formulated with the oil fraction completely oxidized. Results show a negligible effect of U. ohnoi meal on protein digestion when included in feeds at levels of 10% or less. Moreover, results of growth and feed use evidenced the possibility of using up to 5% inclusion of algal meal in feeds without adverse effects on the zootechnical parameters, while the enzyme pretreatment was ineffective to improve its nutritional use. Finally, the inclusion of U. onhoi in feeds determined both an immunostimulatory effect, evidenced by an increase in skin mucus lysozyme in the two mentioned fish species, and a positive influence on the oxidative metabolism of seabream when fed on a diet including rancid oil.This research was funded by the Excellence Campus of Marine Science (CEIMAR) within the "III Call for Innovative Projects in the field of Blue Economy"

    Sociology of caprine production systems in western Pampa

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    Goat ranches in the west area of La Pampa Province (Argentina) are analyzed by mean of surveys. These are long tradition family enterprises (2.5 man equivalent) with owners (average 53.3 years old) that believe in the continuity of their farms. The educational level is very low (about 80 percent are real or functional illiterates), although 46 percent of their inheritors had completed the primary school and 15 percent had completed the high school. Technical assistance is received mainly from governmental programs. Kids are the main sale product and about 18 percent of them are used for family feeding. Other source of income would be increased adding value by mean of handmade manufacture (cheese, hair, spinning, tan leather, etc.)Mediante encuesta se estudian las explotaciones caprinas del oeste pampeano (Argentina). Son empresas familiares (2,5 equivalentes hombre), de larga tradición cuyos responsables, de bastante edad (53,3 años), confían en la continuidad de las explotaciones. El nivel educativo es muy bajo (alrededor del 80 p.100 son analfabetos reales o funcionales), aunque entre los posibles herederos el 46 p.100 ha completado la escuela primaria y el 15 p.100 la secundaria. El apoyo técnico que reciben corresponde casi exclusivamente a programas estatales. El cabrito para venta es el principal producto registrándose un 18 p.100 de autoconsumo. Otras fuentes de ingreso podrían potenciarse agregándoles valor por medio de procesos artesanales de elaboración (quesos, hilado de pelo, curtidos de cueros, etc.)

    Aceite de oliva virgen y regulación hormonal de la presión arterial: una revisión del papel de los enzimas proteolíticos

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    Numerosos estudios realizados en los últimos años, han puesto de manifiesto que los niveles elevados de grasa en la dieta están directamente relacionados con el desarrollo de diversas patologías, entre las que destacan enfermedades cardiovasculares, diabetes o incluso diversos tipos de cánceres. Estudios epidemiológicos también han demostrado que no sólo es importante la cantidad, sino también el tipo de grasa de la dieta. Son especialmente conocidos los efectos beneficiosos de la dieta mediterránea, caracterizada entre otros aspectos, por un consumo elevado de ácidos grasos monoinsaturados como el oleico. En cualquier caso, no se conoce con exactitud las relaciones existentes entre el tipo de grasa de la dieta y el desarrollo de las distintas patologías. Las aminopeptidasas son enzimas proteolíticos implicados en una amplia variedad de procesos biológicos, destacando su papel en el control de la presión arterial a través del sistema renina-angiotensina. En esta revisión se estudia la influencia de una dieta enriquecida en aceite de oliva sobre la actividad aminopeptidásica sérica y de tejidos periféricos, analizando su influencia en la regulación del sistema renina-angiotensina para el control de la presión arterial y el balance de líquidos y electrolitos.The intake of high fat dietary levels is related to the development of several pathologies such as cardiovascular diseases, diabetes and cancer. However, epidemiological studies have demonstrated that not only the amount but also the type of dietary fat participates in the origin of the diseases. In fact, several important beneficts have been attributed to the Mediterranean diet, characterized by the high intake of monoinsaturated fatty acids such as oleic acid preferently. In any case, the relationship between the type of dietary fat an the development of diseases are unknown. Aminopeptidases are proteolytic enzymes involved in several biological proccesses, regulating blood pressure through the renin-angiotensin system. In this review, the influence of an olive oil-enriched diet is presented, analyzing their role in the regulation of blood pressure, local blood flow and fluid and electrolytic balance among other functions

    Milk production and adjustment of lactation curve in the Florida caprine breed

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    Milk yield and average lactation curves is studied in the Florida caprine breed. 968 valid lactations are analyzed corresponding to 317 females kept under a semi-extensive management system, fed by grazing and additional in the feeding rack, with an average feed intake of 1783 g/day of dry matter in autumn-winter, 2938 g/day in spring and 1974 g/day in summer. The milking was done in the morning, and the milk control monthly. Milk production was determined with the adaptation of Carré to the Fleischmann method. A 71.6 percent of the lactations have a duration that fluctuates between 188 and 341 days, being the average duration 301.5 ± 3 days. The lactations that initiate in winter-spring are of shorter than the ones of summer-autumn (288.4±3.6 days vs 315.5±5.2 days), the same as the first lactation in comparison to the rest (283.7±4.8 days vs 310.5±3.8 days). The type of kidding doesn"t affect significantly the duration of the lactation. The milk yield to 210, 240, 270 days and complete lactation is 475.3±4.3 kg, 538.9±5.0 kg, 598.5±6.3 kg and 611.4±7.8 kg, respectively. The females that kid in winter-spring produce more quantity of milk until 270 days of lactation, although their production is less at complete lactation due to its shorter duration. The primiparous goats produce a 19-20 percent less quantity of milk than the multiparous goats, while the ones that kid more than one kid produce a 38-40 percent more than the ones having a simple kid or abortions. The Inverse polynomial and Incomplete gamma functions present a similar adjustment (R2= 0.943; CME=0.5361 and 0.5365), although they show differences in the components of the lactation curve: the initial production is estimated in 0.82 kg/d and 2.56 kg/d; maximum production in 2.71 kg/d and 2.68 kg/d; the peak production at day 27 and 13, and the decrese in 4.58 g/d and 4.32 g/d, respectively.Se estudia la producción láctea y la curva de lactación en caprinos de raza Florida. Se analizan 968 lactaciones válidas correspondientes a 317 hembras manejadas en un régimen semiextensivo, alimentadas a pasto más suplementación en pesebre, con un nivel de ingesta medio de 1783 g/día de materia seca en otoño-invierno, 2938 g/día en primavera y 1974 g/día en verano. El ordeño se efectuaba por la mañana, y el control lechero se realizaba mensualmente. La producción de leche se determinó con la adaptación de Carré al método de Fleishmann. El 71,6 p.100 de las lactaciones tienen una duración comprendida entre 188 y 341 días, siendo la duración media de 301,5±3 días. Las lactaciones que se inician en invierno-primavera son más cortas que las de verano-otoño (288,4±3,6 días vs 315,5±5,2 días), al igual que la primera lactación frente a las restantes (283,7±4,8 días vs 310,5±3,8 días). El tipo de parto no afecta significativamente la duración de la lactación. La producción de leche tipificada a 210, 240 y 270 días y a lactación completa es de 475,3±4,3 kg, 538,9±5,0 kg, 598,5±6,3 kg y 611,4±7,8 kg, respectivamente. Las hembras que paren en invierno- primavera producen mayor cantidad de leche hasta 270 días de lactación, en tanto que su producción es menor a lactación completa por su menor duración. Las cabras primíparas producen un 19-20 p.100 menos cantidad de leche que las multíparas, mientras que las que paren más de un cabrito producen un 38-40 p.100 más que las de parto simple o abortos. Las funciones Polinomial inversa y Gamma incompleta presentan un ajuste similar (R2= 0,943; C.M.E= 0,5361 y 0,5365), aunque muestran diferencias en las componentes de la curva de lactación: la producción inicial se estima en 0,82 kg/d y 2,56 kg/d, la producción máxima en 2,71 kg/d y 2,68 kg/d, el pico de lactación al día 27 y 13, y el descenso en 4,58 g/d y 4,32 g/d, respectivamente

    Real-World Safety and Effectiveness Evidence of a Microcrystalline Tyrosine-Associated Mite Allergoid in Children and Adolescents with Allergic Rhinitis

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    Rinitis al·lèrgica; Infants i adolescents; Tirosina microcristal·linaRinitis alérgica; Niños y adolescentes; Tirosina microcristalinaAllerghic rhinitis; Children and adolescents; Microcrystalline tyrosineEvidence regarding allergen immunotherapy (AIT) in pediatric population is scarce. We have assessed safety and effectiveness of subcutaneous AIT with a microcrystalline tyrosine (MCT)-associated mite allergoid, Acarovac Plus®, in children and adolescents with allergic rhinitis (AR), with and without asthma, in the real-world setting. This was a retrospective, multicenter study including children and adolescents aged 5 years to 17 years with AR, with and without asthma, and sensitized to mites, receiving AIT with Acarovac Plus® during ≥6 months. Primary and secondary objectives were safety and effectiveness, respectively. Effectiveness variables were assessed during 12 months before and after AIT and included unscheduled visits to the healthcare center and emergency room admissions, rhinitis and asthma symptoms according to ARIA and GEMA classifications, respectively, medication use, and patients’ and physicians’ disease perception graded on a visual analog scale (VAS). All 79 patients included had a mean (SD) age of 12.7 (3.3) years. Two patients experienced systemic adverse reactions (none severe). Unscheduled visits to the healthcare center and emergency room admissions decreased (mean (SD) 3.02 [2.48] and 0.63 [1.35] vs. 1.08 [1.38] and 0.09 [0.38], before and after treatment, p < 0.001 and p = 0.001, respectively). After AIT, rhinitis and asthma classification changed (p < 0.0001 for all classifications), showing improvements in symptoms and a significant decrease in rhinitis and use of medication for asthma and VAS scores grading patients’ and physicians’ disease perception (p < 0.001). In conclusion, these results show that AIT with an MCT-associated mite allergoid appears safe and effective in children and adolescents with AR treated in the real-world setting.This study was supported by Allergy Therapeutics Ibérica

    Instructional Changes Adopted for an Engineering Course: Cluster Analysis on Academic Failure

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    As first-year students come from diverse backgrounds, basic skills should be accessible to everyone as soon as possible. Transferring such skills to these students is challenging, especially in highly technical courses. Ensuring that essential knowledge is acquired quickly promotes the student’s self-esteem and may positively influence failure rates. Metaphors can help do this. Metaphors are used to understand the unknown. This paper shows how we made a turn in student learning at the University of Almeria. Our hypothesis assumed that metaphors accelerate the acquisition of basic knowledge so that other skills built on that foundation are easily learned. With these goals in mind, we changed the way we teach by using metaphors and abstract concepts in a computer organisation course, a technical course in the first year of an information technology engineering degree. Cluster analysis of the data on collective student performance after this methodological change clearly identified two distinct groups. These two groups perfectly matched the before and after scenarios of the use of metaphors. The study was conducted during 11 academic years (2002/2003 to 2012/2013). The 475 observations made during this period illustrate the usefulness of this change in teaching and learning, shifting from a propositional teaching/learning model to a more dynamic model based on metaphors and abstractions. Data covering the whole period showed favourable evolution of student achievement and reduced failure rates, not only in this course, but also in many of the following more advanced courses.The paper is structured in five sections. The first gives an introduction, the second describes the methodology. The third section describes the sample and the study carried out. The fourth section presents the results and, finally, the fifth section discusses the main conclusions
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