Analysis of Renewable Energy Policies Related to Repowering the Wind Energy Sector: the Spanish Case

In countries that started early with wind energy, the old wind turbines were located in places where the wind is often very good. Since the best places in which the wind is concerned are occupied by old wind turbines (with lower capacity than the more recent ones) the trend is to start replacing old turbines with new ones. With repowering, the first generation of wind turbines can be replaced by modern multi-megawatt wind turbines. The aim of this article is to analyze energy policies in the Spanish energy sector in the repowering of wind farms from the viewpoint of the current situation of the wind energy sector. The approach presented in this article is meant to explain what have been the policies related to the repowering sector making a brief analysis of the spectrum of different stimulii that are demanded by the market analyzing also the future perspectives of the repowering sector by establishing the new opportunities based on the new published regulations

Food Safety Management in a Global Environment: The Role of Risk Assessment Models

Quantitative risk assessment models are playing a minor role in the development of the new EU legal framework for food safety. There is a tendency of the EU institutions to apply the precautionary principle versus the predisposition of the USA institutions to rely on risk analysis. This paper provides a comparison of the role played by quantitative risk assessment models in the development of new policies on food safety in the EU and in the USA, focusing on a study case: the supply chain of shell eggs. We suggest that EU regulatory bodies should reconsider the role that quantitative risk assessment models have to play in order to design more effective food safety management systems.Food safety policy, food safety assurance, risk analysis, risk assessment, precautionary principle, Food Consumption/Nutrition/Food Safety,

Cycle of Knowledge in the Management of the Supply Chain of Corn for Human Consumption

The objective of this study is to characterize the cycle of knowledge in the supply chain of the industry of corn for human consumption. White corn is cultivated almost exclusively for human consumption and it has a significant value in the food supply in countries whose diet has a high proportion of this variety of corn, such as: Venezuela, México and Colombia in America, and the Republic of South Africa and Sahel countries in Africa. Corn is produced in Venezuela, under rainfed conditions and in a highly mechanized production system. The cycle of knowledge is defined as a progressive spiral in which knowledge is created, stored, transferred, applied and preserved, in order to increase the competitiveness and  sustainability of organizations and companies in the food supply chain. This non experimental and crosssectional research is of a descriptive type. It was conducted in Venezuela during the second semester of 2009 in the supply chain of white corn, specifically, at the level of first tier producers (primary sector). The population is constituted by 1,754 producers of corn in the most important producing regions of the country. The representative sample was selected by the stratified sampling technique with proportional allocation: by association of corn producers and according to the grain yield. A questionnaire was designed and conducted according to the structured survey method. Its validity was verified by discriminant tests of items and its reliability through Bartlett's test, variance factorial analysis, Kaiser/Meyer/Olkin and Cronbach Alpha, achieving the last one a value of 0.9276.The production units have an average area of 67.17 ha, with 1.97 permanent workers and 4.06 temporary workers. They obtained a physical productivity of 4,210.45 kg/ha. The Knowledge Index (KI) achieved a value of 69.78% and the Perception Index of the results (PI) was 76.06%. The Pearson correlation among these indices was positive and significant with a value of 0.51. The factorial analysis for principal components with rotated factors allows obtaining four factors from the five dimensions originally considered. These factors are: (1) knowledge creation, (2) knowledge storage, (3) knowledge transfer and application, and (4) preservation of knowledge.The results allow us to conclude that the cycle of knowledge is managed in four stages in an intuitive and predominantly tacit manner which is the reason why those practices related to explicit knowledge become the agents of differentiation. Moreover, the existence of a positive correlation between the Knowledge Index and the Perception Index of the positive results by the producer was also proven

Assembly and instrumentation of a didactic bench for testing of starters of internal combustion engines

La medición instantánea de velocidad angular en volantes de inercia se ha usado, entre otras aplicaciones, en pruebas experimentales de motores de combustión interna para diagnosticar fallas, particularmente se ha implementado para evaluar las curvas de desempeño de motores de arranque y el estado inicial de las baterías. El presente artículo se enfoca en el desarrollo de un banco de pruebas didáctico basado en volante para realizar el diagnostico de desempeño de motores de arranque hasta de 3 kW, arrancadores eléctricos de motores de combustión interna de hasta 3 litros de cilindrada, propios de automóviles comerciales. Se describen las características principales del banco diseñado: elementos mecánicos, estructurales y accesorios; captadores de desplazamiento angular, corriente y voltaje de arranque, sistemas de lectura, tratamiento y presentación de información. Se emplea un sensor inductivo para la detección de la posición angular de un volante de inercia dotado de corona dentada; la señal análoga es convertida a digital y procesada digitalmente en un código escrito en Matlab®. Durante el ensayo del motor de arranque de prueba, se determina la variación de la potencia eléctrica entregada por éste y la variación de la velocidad angular del sistema de carga (volante) desde su inicio hasta la estabilización. La información experimental adquirida permite construir y analizar los perfiles de comportamiento de velocidad angular, intensidad de corriente, tensión y potencia eléctrica instantáneas. La contrastación, frente a las formas de características de los motores de arranque comerciales, del comportamiento de las señales de voltaje, corriente y potencia consumida del motor de arranque probado en el banco construido, permiten concluir sobre la idoneidad del banco y de la metodología concebida para realizar pruebas didácticas de caracterización y diagnóstico de motores de arranque en el Laboratorio de Máquinas de Combustión Interna de la Universidad Tecnológica de Pereira.The instantaneous measurement of angular speed in flywheels has been used, among other applications, in experimental tests of internal combustion engines to diagnose their working conditions; particularly it has been implemented to evaluate the performance curves of starter motors and the battery conditions. This article focuses on the development of a flywheel-based didactic test bench to diagnose performance of starters of up to 3 kW power, installed in internal combustion engines of up to 3 liters of displacement, typical of commercial cars. The main features of the designed bench are described: mechanical elements, structural elements and accessories; angular displacement, current and starting voltage sensors and systems for reading, processing and presentation of information. An inductive sensor is used for the detection of the angular position of a flywheel equipped with a toothed crown; the analog signal is converted to digital and digitally processed in a code written in Matlab®. During the test of the testing starter motor, the variation of the electric power delivered by it and the variation of the angular speed of the charging system (flywheel) from its initial state to stabilization are determined. The acquired experimental information is used to construct and analyze the behavior profiles of instantaneous angular speed, current intensity, voltage and electrical power. Confronting the forms of characteristics of commercial starters provided by the starter manufacturers, with those of the voltage, current and consumed power signals of the starter tested in the built bench, allows us to conclude on the suitability of the designed test bench and the conceived methodology to carry out didactic characterization and diagnosis tests of starter motors in the Laboratory of Internal Combustion Engines of the Technological University of Pereira

Efecto de suplementación con forrajes verdes sobre parámetros productivos y calidad de huevo en gallinas

In Colombia, poultry production is an important source of food, providing protein of good quality animal origin such as eggs and meat; however, due to the high costs of concentrates, the need to search for food alternatives has been generated. The objective of this work was to determine the effect of the consumption of green forages of Alfalfa (Medicago sativa), Mulberry (Morus alba) and Buttercup (Tithonia diversifolia) in productive parameters and egg quality. Four treatments were established with a base feed of commercial balanced concentrate and water ad libitum; T1: supplementation with Alfalfa, T2: with Mulberry, T3: Buttercup and T4: control group. The parameters evaluated were: weight, percentage of laying, feed consumption, egg weight, pigmentation and weight of the yolk, weight and density of albumin, weight and thickness of the shell and Haugh units. The T2 birds showed statistically significant differences (p <0.05) in body weight in the first study interval and in yolk pigmentation in the three intervals with slightly higher values. Mulberry supplementation significantly improves bud pigmentation without negatively affecting productive parameters.En Colombia, la producción avícola es una fuente importante de alimento aportando proteína de origen animal de buena calidad como huevos y carne, sin embargo, al presentarse altos costos en los concentrados se ha generado la necesidad de búsqueda de alternativas de alimentación. El objetivo de este trabajo fue determinar el efecto del consumo de forrajes verdes de Alfalfa (Medicago sativa), Morera (Morus alba) y Botón de oro (Tithonia diversifolia) en parámetros productivos y calidad de huevo. Se establecieron cuatro tratamientos con una alimentación base de concentrado balanceado comercial y agua a voluntad; T1: suplementación con Alfalfa, T2: con Morera, T3: Botón de oro y T4: grupo control. Los parámetros evaluados fueron: peso, porcentaje de postura, consumo de alimento, peso del huevo, pigmentación y peso de la yema, peso y densidad de la albumina, peso y espesor de la cascara y las unidades Haugh. Las aves del T2, mostraron diferencias estadísticamente significativas (p<0,05) en el peso corporal en el primer intervalo de estudio y en la pigmentación de la yema en los tres intervalos con valores levemente superiores. La suplementación con morera mejora significativamente la pigmentación de la yema sin afectar negativamente los parámetros productivos

Histological Characteristics of Gills and Dorsal Skin in Ambystoma leorae and Ambystoma rivulare: Morphological Changes for Living at High Altitude

Vertebrates exhibit structural changes in their cardiovascular and gas exchange systems in response to hypoxic conditions in high altitude environments. In highland neotenic mole salamanders, as other amphibians, the majority of gases exchange is carried out for skin and gills. But, in high altitude environments, the available oxygen is lower than it is in the air thus, the scarcity of oxygen limits the survival of organisms. Many studies on this subject have focused on understanding the hematological mechanisms that amphibians exhibit in response to hypoxia. However, little is known about possible morphological changes in respiratory structures that may permit increased gas exchange during respiration in high altitude amphibians like Ambystoma leorae and A. rivulare, two threatened Mexican salamander species. The aim of the present study was to describe and compare the histological characteristics of the gills and dorsal skin of A. leorae and A. rivulare from populations at low and high altitudes. We found that, in comparison to lowland organisms, highland ones exhibited more pronounced skin folds, greater numbers of secondary branches in the gills, thinner dorsal and gill epidermises, and greater quantity of melanin surrounding the gill blood vessels. These differences permit a greater capacity for gas exchange and also increase thermoregulatory capacity in high altitude environments.Consejo Nacional de Ciencia y Tecnología (grant 178723) Secretaría de Medio Ambiente y Recursos Naturales (SGPA/DGVS/02407/13)

Detección de conductas de riesgo para contraer enfermedades de transmisión sexual / VIH-SIDA y propuesta de prevención a través de la formación integral de los estudiantes de primer semestre de la Universidad del Magdalena

Esta publicación, es el resultado de la investigación como prueba piloto desarrollada en la Universidad del Magdalena, la cual recoge la experiencia de los investigadores y la participación de los estudiantes de primer semestre, para detectar las conductas de riesgo para contraer enfermedades de transmisión sexual/VIH-SIDA, para diseñar a partir de los resultados, una propuesta pedagógica que logre la promoción de la salud sexual y la prevención de las enfermedades de transmisión sexual, como contribución a la formación integral de los estudiantes. El problema de investigación surge del compromiso que tiene la UNIMAG, de contribuir con la formación integral de los estudiantes, en este caso en la detección de conductas de riesgo de contraer una enfermedad de transmisión sexual en los estudiantes de primer semestre con el propósito de intervenir dichas conductas a través de la educación, el deporte, la atención interdisciplinaria y la remisión a las IPSs, públicas y privadas. Como contribución al mejoramiento de la calidad de vida y el rendimiento académico que conllevan a la formaciónintegral de los estudiantes. marco de referencia: Se enfoca hacia una descripción analítica de los cambios psicosociales que sufren los estudiantes en la transición colegio - Universidad, los cuales están expuestos a múltiples eventos que los hacen vulnerables y expuestos a contraer una enfermedad de transmisión sexual, si no se realizan acciones de tipo pedagógico y profiláctico que logren prevenir dichas eventualidades. marco textual: Estudiantes de primer semestre de la UNIMAG. Se relaciona puntualmente con los fines y propósitos del P.EJ. dentro del marco de Refundación de esta institución educativa, siendo una prueba piloto como preámbulo hacia una investigación consolidada que sirva de apoyo pedagógico y metodológico como contribución a la formación integral. metodología: Investigación Acción de carácter cualitativo (prospectiva de cohorte transversal) cuyos niveles de formación están dados en la interacción que surge en la práctica pedagógica durante el proceso investigativo y los participantes del evento, para desarrollar acciones conjuntas que se lleven a la acción y contribuyan en la solución de problemas comunes. Conclusión: la presente Investigación Acción como prueba piloto, ha sido lograda gracias a la colaboración de la comunidad Educativa de la UNIMAG y los investigadores, realizando una labor pedagógica y de sondeo piloto como muestra para una investigación más amplia y de mayor cobertura, que logre desarrollar un programa de acción educativa y promoción de la salud sexual, contribuyendo a mejorar la calidad de vida de los estudiantes

Les droits disciplinaires des fonctions publiques : « unification », « harmonisation » ou « distanciation ». A propos de la loi du 26 avril 2016 relative à la déontologie et aux droits et obligations des fonctionnaires

The production of tt‾ , W+bb‾ and W+cc‾ is studied in the forward region of proton–proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98±0.02 fb−1 . The W bosons are reconstructed in the decays W→ℓν , where ℓ denotes muon or electron, while the b and c quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions.The production of $t\overline{t}$, $W+b\overline{b}$ and $W+c\overline{c}$ is studied in the forward region of proton-proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98 $\pm$ 0.02 \mbox{fb}^{-1}. The $W$ bosons are reconstructed in the decays $W\rightarrow\ell\nu$, where $\ell$ denotes muon or electron, while the $b$ and $c$ quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions

Study of the B−→Λc+Λˉc−K−B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-} decay

The decay $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ is studied in proton-proton collisions at a center-of-mass energy of $\sqrt{s}=13$ TeV using data corresponding to an integrated luminosity of 5 $\mathrm{fb}^{-1}$ collected by the LHCb experiment. In the $\Lambda_{c}^+ K^{-}$ system, the $\Xi_{c}(2930)^{0}$ state observed at the BaBar and Belle experiments is resolved into two narrower states, $\Xi_{c}(2923)^{0}$ and $\Xi_{c}(2939)^{0}$, whose masses and widths are measured to be $$m(\Xi_{c}(2923)^{0}) = 2924.5 \pm 0.4 \pm 1.1 \,\mathrm{MeV}, \\ m(\Xi_{c}(2939)^{0}) = 2938.5 \pm 0.9 \pm 2.3 \,\mathrm{MeV}, \\ \Gamma(\Xi_{c}(2923)^{0}) = \phantom{000}4.8 \pm 0.9 \pm 1.5 \,\mathrm{MeV},\\ \Gamma(\Xi_{c}(2939)^{0}) = \phantom{00}11.0 \pm 1.9 \pm 7.5 \,\mathrm{MeV},$$ where the first uncertainties are statistical and the second systematic. The results are consistent with a previous LHCb measurement using a prompt $\Lambda_{c}^{+} K^{-}$ sample. Evidence of a new $\Xi_{c}(2880)^{0}$ state is found with a local significance of $3.8\,\sigma$, whose mass and width are measured to be $2881.8 \pm 3.1 \pm 8.5\,\mathrm{MeV}$ and $12.4 \pm 5.3 \pm 5.8 \,\mathrm{MeV}$, respectively. In addition, evidence of a new decay mode $\Xi_{c}(2790)^{0} \to \Lambda_{c}^{+} K^{-}$ is found with a significance of $3.7\,\sigma$. The relative branching fraction of $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ with respect to the $B^{-} \to D^{+} D^{-} K^{-}$ decay is measured to be $2.36 \pm 0.11 \pm 0.22 \pm 0.25$, where the first uncertainty is statistical, the second systematic and the third originates from the branching fractions of charm hadron decays.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-028.html (LHCb public pages