197 research outputs found
Cover crops effect on farm benefits and nitrate leaching: Linking economic and environmental analysis.
Introducing cover crops (CC) interspersed with intensively fertilized crops in rotation has the potential to reduce nitrate leaching. This paper evaluates various strategies involving CC between maize and compares the economic and environmental results with respect to a typical maize?fallow rotation. The comparison is performed through stochastic (Monte-Carlo) simulation models of farms? profits using probability distribution functions (pdfs) of yield and N fertilizer saving fitted with data collected from various field trials and pdfs of crop prices and the cost of fertilizer fitted from statistical sources. Stochastic dominance relationships are obtained to rank the most profitable strategies from a farm financial perspective. A two-criterion comparison scheme is proposed to rank alternative strategies based on farm profit and nitrate leaching levels, taking the baseline scenario as the maize?fallow rotation. The results show that when CC biomass is sold as forage instead of keeping it in the soil, greater profit and less leaching of nitrates are achieved than in the baseline scenario. While the fertilizer saving will be lower if CC is sold than if it is kept in the soil, the revenue obtained from the sale of the CC compensates for the reduced fertilizer savings. The results show that CC would perhaps provide a double dividend of greater profit and reduced nitrate leaching in intensive irrigated cropping systems in Mediterranean regions
Criação e aplicação de um modelo baseado em Topic Maps à documentação educativa
As políticas da União Europeia para a sociedade da informação estão a promover um modelo educativo baseado na aquisição de competências e na aprendizagem ao longo da vida. A eficácia da aprendizagem neste modelo educativo assenta numa educação digital, na qual os recursos digitais estruturam, organizam e representam o seu conteúdo de acordo com as suas potencialidades educativas. Descrevem-se os passos prosseguidos na aplicação da norma ISO/IEC 13250:2000 Topic Maps como escolha para a organização e representação do conhecimento de uso educativo, adaptando a recuperação deste tipo de informação a um modelo de aprendizagem centrado no educando, tal como as actuais políticas europeias promovem. Numa primeira parte apresenta-se a análise realizada sobre as várias metodologias para a representação do conhecimento: thesaurus, mapas conceptuais e ontologias. Discutem-se as características que levaram à selecção dos Topic Maps como a metodologia a ser utilizada neste projecto. Numa segunda parte, apresenta-se a norma ISO/IEC 13250:2000 Topic Maps e discute-se de que forma nos irá auxiliar a criar um ambiente de aprendizagem centrado no educando e utilizando os recursos educativos (objectos de ensino, artigos, monografias, teses, etc) disponíveis na Web. Por fim, numa terceira parte, apresenta-se uma arquitectura funcional capaz de suportar a metodologia seleccionada e o cenário de aplicação: especificação de mapas conceptuais orientados a programas educativos dinâmicos e que reagem às interacções dos educandos; agregação de conteúdos disponíveis na Web com o objectivo de criar um repositório de objectos de ensino (utilização do protocolo OAI-PMH); definição de estratégias para a população do mapa conceptual com os conteúdos recolhidos da Internet; exploração do repositório a partir do mapa conceptual. Em conclusão, iremos demonstrar que já é possível criar um ambiente com estas características utilizando vários componentes e tecnologias existentes mas, também, que é necessário fazer algum trabalho de integração e normalização.Policies of the European Information Society are to promote an educational model based on the acquisition of skills and lifelong learning. The effectiveness of learning in this educational model is based on a digital education, in which digital resources structure, organize and represent its content according to their educational potential. We describe the steps pursued in the implementation of ISO / IEC 13250:2000 Topic Maps as the selected methodology adopted for the organization and representation of knowledge of educational use, adapting the retrieval of such information to a student-centered learning model, as the current European policies promote. The first part presents the analysis on the various methodologies for the representation of knowledge: thesaurus, concept maps and ontologies. In the following we discuss the characteristics that led to the selection of Topic Maps as the methodology to be used in this project. The second part presents the ISO / IEC 13250:2000 Topic Maps, and discusses how it will help to create an environment focused on student learning through the use of educational resources (learning objects, articles, monographs, theses, etc.) available on the Web. Finally, a third part presents a functional architecture capable of supporting the selected methodology and the application scenario: specification of concept maps, oriented educational programs and dynamic interactions that respond to the students; content aggregation available on the Web in order to create a repository of learning objects (using OAI-PMH), strategies for the population of the conceptual map with the contents collected from the Internet, holding the repository from the conceptual map. In conclusion, we demonstrate that it is possible to create an environment with these features using several existing technologies and components, but also that some work for integration and standardization is needed
Instrumentos de utilidad en el análisis de contenido para la organización de documentos digitales educativos
Las políticas de la Unión Europea para la sociedad de la información están impulsando un modelo educativo basado en adquisición de competencias y el aprendizaje a lo largo de la vida. La eficacia del aprendizaje en este modelo educativo descansa en una educación digital, en la que los recursos digitales estructuren, organicen y representen su contenido acorde con sus potencialidades educativas. La Biblioteconomía y Documentación puede contribuir a su consecución mediante la actualización de sus instrumentos a partir de su diseño conceptual en el análisis documental del contenido. Se analizan tesauros, mapas conceptuales y ontologías, que constituyen diversos sistemas de representación del conocimiento procedentes de diferentes disciplinas, y se realiza una comparativa en cuanto a su eficacia para la organización de contenidos en educación para el espacio digital.The European Union’s Information Society policies are promoting an educational model based on the acquisition of skills and support for lifelong learning. The effectiveness of learning in this educational model lies in digital education, where digital resources structure, organize and represent their contents according to their educational potential. Information Science can play a role here by updating tools and instruments from content analysis conceptual design.Thesauri, concept maps, and ontologies are analyzed, because they are different knowledge representation systems which come from different disciplines. A comparison of these instruments is conducted in terms of their effectiveness in organising educationbased contents in cyberspace.Publicad
La medición de impacto y evaluación de programas de alfabetización en información para bibliotecas escolares
Se analiza el planteamiento teórico, desarrollo metodológico y aproximación a unos primeros resultados de un proyecto de investigación aplicada, financiado por el Ministerio de Educación, para la propuesta de un modelo de indicadores competenciales de alfabetización en información en bibliotecas escolares. A partir de la consideración de la alfabetización en información como competencia para conocer y saber en red y la biblioteca escolar como Centro de Recursos para la Enseñanza y el Aprendizaje (CREA), se plantean, siguiendo propuestas ya enunciadas, como objetivos el diseño de indicadores cualitativos para medir el progreso y la calidad de programas de alfabetización en información para bibliotecas escolares. Se presenta la formulación del modelo de indicadores, categorizado en destrezas, habilidades y competencias, plasmado luego en un cuestionario-tipo según niveles educativos y sobre unos recursos digitales seleccionados, que fue pre-testado para su aplicación en Asturias, Navarra y Madrid. Se describe su aplicación en las tres comunidades, la naturaleza de las cuestiones, el procesamiento de datos y una aproximación a un primer análisis interpretativo por niveles educativos. Se aborda, finalmente, la argumentación de unas primeras conclusiones a modo de desarrollos futuros del proyecto y recomendaciones para el desarrollo de la Sociedad del conocimiento, a partir de un eficaz plan de programas de alfabetización en información desde bibliotecas escolares transformadas en CREA.This article analyzes the theoretical approach and methodological development
of a project of applied research, as well as offering an approximation to the early results.
The aim of the project, fi nanced by the Ministry of Education, was to propose a model
of indicators for information literacy competency for school libraries. In considering information literacy as a competency for knowing and learning via networks, and the school library as a Teaching and Learning Resource Center, the authors propose a design for qualitative indicators to measure the progress and quality of information literacy programs in school libraries. The design of the model of indicators is presented, with the model categorized according to skills, abilities and competencies. These criteria were introduced into a questionnaire based on educational levels and covering selected
digital resources. The applicability of this tool was tested in Asturias, Navarre and Madrid. The application of the questionnaire in these three regions of Spain, the nature
of the questions, the processing of the resulting data, and an initial interpretative
analysis by educational levels are described. Finally some initial conclusions are put forward for a future project, as are recommendations for developing a Knowledge Society beginning with an effective plan for information literacy programs in school libraries to be transformed into Teaching and Learning Resource Centers.Ministerio de Educación y Ciencia (ORDEN ECI/754/2008, de 10 de marzo, por la que se conceden ayudas para la elaboración de materiales para facilitar la lectura en las diferentes áreas y materias del currículo y para la realización de estudios sobre la lectura y las bibliotecas escolares, convocadas por Orden ECI/2687/2007, de 6 de septiembre, Modalidad C.)Publicad
Resposta hemodinâmica a sílabas modificadas acusticamente em recém-nascidos prematuros e a termo adquirida por espectroscopia do infravermelho próximo
Esta investigación evalúa, en neonatos, la respuesta hemodinámica ante sílabas modificadas acústicamente (pronunciadas de manera prolongada) en comparación con la respuesta a sílabas no modificadas (pronunciadas a una velocidad normal). El objetivo fue evaluar cuál de estas condiciones de estimulación producía una mejor discriminación silábica en dos grupos de neonatos: 13 prematuros (edad gestacional promedio de 30 semanas, DE 3 semanas) y 13 nacidos a término (edad gestacional promedio de 38 semanas, DE 1 semana). La discriminación de sílabas, en cada condición, se evaluó mediante un paradigma oddball (ensayos con sílabas iguales vs. ensayos con sílaba diferente). El análisis estadístico se basó en la comparación de la respuesta hemodinámica [oxyHb] obtenida por espectroscopia de infrarrojo cercano (NIRS) ante ensayos con sílabas iguales Vs. ensayos con una sílaba diferente en cada condición. Se encontró que la condición de sílabas modificadas obtuvo mejores resultados para la discriminación entre ensayos en ambos grupos. La amplitud de la respuesta hemodinámica ante el ensayo con una sílaba diferente fue significativamente mayor que ante el ensayo con sílabas iguales: en recién nacidos a término, t = 2,59, p = 0,024 y en los prematuros, t = 2,38, p = 0,035. Este hallazgo ocurrió en el lóbulo temporal izquierdo. Estos datos sugieren que las sílabas modificadas facilitan el procesamiento de fonemas desde el nacimiento.This research assesses, in newborns, the hemodynamic response to acoustically modified syllables (pronounced in a prolonged manner), versus the response to unmodified syllables (pronounced at a normal rate). The aim was to assess which of these stimulation conditions produced better syllable discrimination in two groups of neonates: 13 preterm (mean gestational age 30 weeks, SD 3 weeks), and 13 full term newborns (mean age 38 weeks, SD 1 week). Syllable discrimination, in each condition, was assessed by using an oddball paradigm (equal syllable trials vs. different syllable trials). The statistical analysis was based on the comparison between the hemodynamic response [oxyHbO] obtained by Near Infrared Spectroscopy (NIRS) to different syllable trials vs. equal syllable trials, in each condition. The modified syllable condition was better in producing trial discrimination in both groups. The amplitude of the hemodynamic response to the different syllable trials was greater than the one to the equal syllable trials: for term infants, t = 2.59, p = 0.024, and for preterm t = 2.38, p = 0.035. This finding occurred in the left temporal lobe. These data suggest that the modified syllables facilitate processing of phonemes from birth.Esta pesquisa avalia, em neonatos, a resposta hemodinâmica diante sílabas modificadas acusticamente (pronunciadas de maneira prolongada) em comparação com a resposta a sílabas não modificadas (pronunciadas a uma velocidade normal). O objetivo foi avaliar qual destas condições de estimulação produzia uma melhor discriminação silábica em dois grupos de neonatos: 13 prematuros (idade gestacional média de 30 semanas, DE 3 semanas) e 13 nascidos a termo (idade gestacional média de 38 semanas, DE 1 semana). A discriminação de sílabas, em cada condição, foi avaliada mediante um paradigma oddball (ensaios com sílabas iguais vs. ensaios com sílaba diferente). A análise estadística se baseou na comparação da resposta hemodinâmica [oxyHb] obtida por espectroscopia de infravermelho próximo (NIRS) ante ensaios com sílabas iguais Vs. ensaios com uma sílaba diferente em cada condição. Encontrou-se que a condição de sílabas modificadas obteve melhores resultados para a discriminação entre ensaios em ambos os grupos. A amplitude da resposta hemodinâmica ante o ensaio com uma sílaba diferente foi significativamente maior que perante o ensaio com sílabas iguais: em recém-nascidos a termo, t = 2,59, p = 0,024 e nos prematuros, t = 2,38, p = 0,035. Este descobrimento ocorreu no lóbulo temporal esquerdo. Estes dados sugerem que as sílabas modificadas facilitam o processamento de fonemas desde o nascimento
Development of a controlled vocabulary for learning objects' functional description in an educational repository
Proceeding of: Metadata for Knowledge and Learning (DC 2006). October 3-6, 2006. Colima, MexicoThis paper presents the development of a controlled vocabulary for functional description in an educational repository project which has adopted a DC application profile. The vocabulary, organized according to the identified functions of educational documents and learning objects' components, permits their retrieval and reuse to be improved.The DOTEINE Project has been financed by the Spanish Interministerial Commission of
Science & Technology (CICYT, ref. BSO2003-04895). The IACORIE Project has been
financed by the Regional Government of Madrid (Comunidad de Madrid, ref.
06/HSE/0165/2004).Publicad
Alfabetización en la información y bibliotecas escolares: una experiencia en la comunidad de Madrid
Una tarea muy ligada a la labor del documentalista, desde una perspectiva histórica, ha sido el apoyo a las políticas de alfabetización, del mismo modo ha sido una constante en España el empeño por establecer las Bibliotecas Escolares en el sistema educativo. La Sociedad de la Información y sus medios para acceder y representar el conocimiento ha desarrollado un nuevo modo de leer y escribir, una nueva alfabetización más próxima al quehacer documentalista, information literacy, alfabetización de la información. En esta comunicación realizamos una semblanza de la Hª de las Bibliotecas Escolares en nuestro país y exponemos las líneas de trabajo y los primeros resultados del Seminario de Investigación y aplicación experimental “Las Bibliotecas Escolares y la Alfabetización en la Información.A task closely linked to the work of the specialist in documentation sciences, from a historical perspective, has been the support to the policy of literacy, and, in the same way, the determination in Spain to set up School Libraries in the educational system. The Information Society and its means to accede and represent knowledge has developed a new pattern for reading and writing, a new education closer to the chore of the documentation sciences, “Information Literacy”, education of the information. In this communication we tackle a biographical out line of the history of School Libraries in our country and we lay out the working lines and the first results of the Seminary of Research and experimental application School Libraries and information literacy. The interest of this contribution lies in offering a group working vision between entities far from each other at times, School and University. From the research in progressive line, Information Literacy we show the very important role that the Documentation can play in a School Library completely adapted to the new technological environments and to the increasing needs of the community of users and generated by the Knowledge SocietyPublicad
Vida social de las bacterias: aquí no hay quien viva
Desde hace varias décadas se están estudiando las relaciones interactivas que presentan las bacterias. A día de hoy se ha confirmado la existencia de sistemas de envío de información propia, así como el establecimiento de niveles de altruismo, cooperación, competición o incluso canibalismo. Por ello, los microbiólogos han establecido un símil entre el comportamiento de las bacterias en un mismo ecosistema, con el comportamiento de las comunidades animales y de los seres humanos. Así, se comienza a hablar de “sociomicrobiologia” bacteriana.En el presente trabajo se detallan dos tipos de comportamientos bacterianos, el canibalismo y la formación de biofilms. Así mismo se explican los mecanismos de comunicación célula-célula, el quórum sensing y los plásmidos, que permiten el establecimiento de un comportamiento más o menos global con un funcionamiento común.For several decades the bacterial interactive relationship have been studied. Today incredible discoveries confirm the existence of information systems, as well as the establishment of altruism, cooperation, competition or even cannibalism levels. The researchers have settled down a resemblance between the behavior of the bacteria in a same ecosystem, with the behaviour of the animal communities and human beings. Thus, it is begun to speak of bacterial “sociomicrobiology”.In the present work two types of bacterian behaviour are detailed, the cannibalism and the formation of biofilms, Also are explained the mechanisms of communication cell-cell, the quorum sensing and the plásmidos ones, that allow the establishment of, more or less, a global behavior with a common operation
Variables used in questionnaires about ergonutritionals supplements intake
Introducción: el consumo de suplementos ergonutricionales está aumentando en los últimos años tanto en España como en el resto del mundo. Los cuestionarios que estiman la ingesta y uso de suplementos presentan limitaciones metodológicas. El objetivo de este estudio es describir las variables utilizadas en los cuestionarios de estimación de consumo de suplementos ergonutricionales para población deportista, descritas en el apartado de metodología de los artículos científicos. Metodología: revisión bibliográfica de variables utilizadas para estimar el uso y consumo de suplementos ergonutricionales. Búsqueda estructurada en la base de datos PubMed y mediante la estrategia bola de nieve. Ecuación de búsqueda: “Questionnaire” AND “Supplementation” AND “Athletes”. Criterios de inclusión: artículos publicados en cualquier país en idioma inglés o en español, que contengan cuestionario en el anexo o las variables que se describen en el apartado de metodología que puedan inferirse a partir de los artículos, que estimen la ingesta y uso de suplementos ergonutricionales y vayan dirigidos a deportistas que entrenan a nivel competitivo (amateurs, élite, etc.). Se realizó un análisis de contenido y un análisis descriptivo. Resultados: de los 122 estudios identificados, 21 cumplieron los criterios de inclusión. Las variables descritas fueron factores sociodemográficos y relacionados con el deporte que se practica, así como la frecuencia de entrenamiento, población deportista a la que iba dirigida, razones/motivos de uso y consumo, fuentes de información, lista de suplementos y frecuencia de uso y consumo. Discusión: existe gran heterogeneidad en cuanto a las variables propuestas por los autores en los cuestionarios de estimación de ingesta y uso de suplementos ergonutricionales. Es necesaria la estandarización de metodologías en el diseño de cuestionarios, así como definir una clasificación de referencia como la propuesta por el Instituto Australiano del Deporte.Introduction: nutritional supplements intake is increasing during the recent years both in Spain and in the rest of the world. Questionnaires that estimate the intake and supplement use have methodological limitations. The purpose of this study is to describe used indicators in questionnaires that estimate nutritional supplements intake among athletes so facilitate understanding of these limitations. Methodology: a literature review of variables used within questionnaires to estimate consumption of nutritional supplements among athletes. We conducted a structured research in PubMed database and through snow ball strategy. Search equation: “Questionnaire” AND “Supplementation” AND “Athletes”. Inclusion criteria: published in any country in English or Spanish, containing questionnaire or indicators can be deducted from the items, to estimate the intake and use of nutritional supplements and should be targeted to athletes training in order to compete at any level. We performed a descriptive analysis. Results: 21 above the 122 identified studies met the inclusion criteria. Sociodemographic factors, sport and training frequency, athlete population, reasons/motives for use and consumption, sources of information and list of supplements and frequency are the found indicators for estimating intake of supplements. Discussion: there are great heterogeneity in terms of the proposed indicators by the authors at the questionnaires and intake estimation using nutritional supplements, standardization of the methodology for the development questionnaires to be necessary and proposing the classification of the Australian Institute of Sport as a reference
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