316 research outputs found
Ethnobiology : the missing link in ecology and evolution
Evolutionary biologists and ecologists increasingly appreciate the value of local knowledge of human communities for research into the past, present, and future of biodiversity. However, there are often significant problems accessing and interpreting this knowledge. Here, we argue that closer interaction with ethnobiologists, who study the relation between humans and the natural world, will enable local knowledge to be better applied in ecological and evolutionary biological research. This will provide more comprehensive answers to the scientific questions being asked, and will result in improved engagement with both academic and non-academic communities
Modelo predictivos de la deserción estudiantil en una universidad privada del Perú
La deserción es un problema que afecta alas universidades, públicas y privadas, y que generan una serie de consecuencias negativas para las instituciones, así como para los mismos jóvenes porque tendrán menos posibilidades de conseguir un empleo que permita bridarles una mejor calidad de vida a sus familias, por ello, el objetivo de este estudio fue determinar cómo el uso de modelos predictivos en asignaturas críticas contribuye a identificar a los estudiantes en riesgo de deserción. Se diseñaron siete modelos predictivos con la metodología CRISP (Cross-Industry Standard Process for Data Mining) y el historial académico de los estudiantes, para ser aplicados en siete cursos críticos. Entre los principales resultados se puede destacar que los modelos predictivos contribuyeron a reducir en un 40 % y 50 % los niveles de desaprobación y las variables que mejor la predijeron fueron la carrera que estudian (vocación), el número de veces que se matriculan en la asignatura y la nota que tuvieron en matemática o comunicación cuando cursaron el quinto año del nivel secundaria.Tesi
Predictive models of student desertion at a private Peruvian university
La deserción es un problema que afecta a las universidades, públicas y privadas, y acarrea una serie de consecuencias negativas tanto para las instituciones como para los mismos jóvenes, por ello, el objetivo de este estudio fue determinar cómo el uso de modelos predictivos en asignaturas críticas contribuye a identificar a los estudiantes en riesgo de deserción. Se diseñaron siete modelos predictivos con la metodología CRISP (Cross-Industry Standard Process for Data Mining) y el historial académico de los estudiantes, para ser aplicados en siete cursos. Entre los principales resultados se puede destacar que los modelos predictivos contribuyeron a reducir en un 25 % y 40 % los niveles de desaprobación y las variables que mejor la predijeron fueron la carrera que estudian (vocación), el número de veces que se matriculan en la asignatura y la nota que tuvieron en matemática o comunicación cuando cursaron el quinto año de secundaria.Desertion is a problem that affects public and private universities, and leads to a series of negative consequences for both institutions and students. Therefore, the objective of this study was to determine how the use of predictive models in low pass-rate courses helps to identify students at risk of desertion. Seven predictive models were designed using CRISP (Cross- Industry Standard Process for Data Mining) methodology and students’ academic records to be applied in seven low pass-rate courses. Among the main results, it can be noted that predictive models contributed to the reduction of fail rates by 25% and 40%, and that the variables that best forecast desertion were career choice (vocation), number of times students enrolled in the course, and grades obtained in mathematics or language arts when students attended the fifth year of high school
Adaptation and diversity along an altitudinal gradient in Ethiopian barley (Hordeum vulgare L.) landraces revealed by molecular analysis
<p>Abstract</p> <p>Background</p> <p>Among the cereal crops, barley is the species with the greatest adaptability to a wide range of environments. To determine the level and structure of genetic diversity in barley (<it>Hordeum vulgare </it>L.) landraces from the central highlands of Ethiopia, we have examined the molecular variation at seven nuclear microsatellite loci.</p> <p>Results</p> <p>A total of 106 landrace populations were sampled in the two growing seasons (<it>Meher </it>and <it>Belg</it>; the long and short rainy seasons, respectively), across three districts (Ankober, Mojanawadera and Tarmaber), and within each district along an altitudinal gradient (from 1,798 to 3,324 m a.s.l). Overall, although significant, the divergence (e.g. F<sub>ST</sub>) is very low between seasons and geographical districts, while it is high between different classes of altitude. Selection for adaptation to different altitudes appears to be the main factor that has determined the observed clinal variation, along with population-size effects.</p> <p>Conclusions</p> <p>Our data show that barley landraces from Ethiopia are constituted by highly variable local populations (farmer's fields) that have large within-population diversity. These landraces are also shown to be locally adapted, with the major driving force that has shaped their population structure being consistent with selection for adaptation along an altitudinal gradient. Overall, our study highlights the potential of such landraces as a source of useful alleles. Furthermore, these landraces also represent an ideal system to study the processes of adaptation and for the identification of genes and genomic regions that have adaptive roles in crop species.</p
Factores que permitan el desarrollo del ecoturismo en los parques nacionales del Perú : una investigación exploratoria
En los últimos años, el ser humano ha tomado cada vez mayor conciencia del daño que está
ocasionándose a sí mismo, a través de la contaminación del medio ambiente. Entonces están
surgiendo corrientes ecologistas que buscan la preservación de aquellas áreas naturales con la
finalidad de mantener intactas algunas zonas de nuestro planeta, en las que el hombre no pueda
ni deba causar daño alguno
Factores que permitan el desarrollo del ecoturismo en los parques nacionales del Perú : una investigación exploratoria
En los últimos años, el ser humano ha tomado cada vez mayor conciencia del daño que está
ocasionándose a sí mismo, a través de la contaminación del medio ambiente. Entonces están
surgiendo corrientes ecologistas que buscan la preservación de aquellas áreas naturales con la
finalidad de mantener intactas algunas zonas de nuestro planeta, en las que el hombre no pueda
ni deba causar daño alguno.Tesi
El cuerpo de Eva en Tomás de Aquino
La constitución del primer cuerpo femenino o el cuerpo de Eva tiene planteos que conllevan problemáticas metafísicas y físicas diversas que han derivado en consecuencias sociales y culturales para la mujer que han atravesado los siglos y llegan hasta la actualidad. La no existencia de progenitores, exige del Aquinate respuestas que exceden lo meramente antropológico y biológico y le conduce a la búsqueda de respuestas más profundas, que, muchas veces están entrelazadas con afirmaciones de carácter teológico y religioso. Tomás de Aquino brinda respuestas de razón aunque el trasfondo sea de fe, e inclusive, con interpretaciones literales de las Sagradas Escrituras actualmente ya abandonadas. No obstante esto, el Aquinate realiza un verdadero esfuerzo intelectual para encontrar respuestas en un ámbito meramente racional pues la materialidad del cuerpo de la primera mujer trae dificultades para su dilucidación y entendimiento. Como en otras partes de su extensa obra, Tomás de Aquino, sigue las obras biológicas y físicas de Aristóteles. Si bien el fondo es aristotélico está en consonancia con el trasfondo cristiano, pues, el Aquinate muestra su extraordinaria capacidad de síntesis entre la fe recibida y la razón argumentada, entre la revelación (y en especial las Sagradas Escrituras en este caso) y los principios de razón.The constitution of the first female body or the body of Eva presents several physical and metaphysical problems, problems that have gone through the centuries and reach the present, generating social and cultural consequences for women. The non-existence of parents demands from Aquino answers that go beyond the anthropological and biological and lead to the search of philosophical answers intertwined with the theological ones. Thomas Aquinas provides rational answers although the background is of faith, and even, with literal interpretations of the Sacred Scriptures now abandoned. The Aquinate makes an intellectual effort to find answers in a rational field because the matter of the body of the first woman brings difficulties for its elucidation and understanding. As in other parts of his extensive work, Thomas Aquinas, follows the biological and physical works of Aristotle. Although the Aristotelian background is in line with Christian thought, Aquinas shows his extraordinary capacity for synthesis between the faith received and reason argued, between revelation (and especially the Holy Scriptures in this case) and the principles of reason
Toward an Evolved Concept of Landrace
[EN] The term "landrace" has generally been defined as a cultivated, genetically heterogeneous variety that has evolved in a certain ecogeographical area and is therefore adapted to the edaphic and climatic conditions and to its traditional management and uses. Despite being considered by many to be inalterable, landraces have been and are in a constant state of evolution as a result of natural and artificial selection. Many landraces have disappeared from cultivation but are preserved in gene banks. Using modern selection and breeding technology tools to shape these preserved landraces together with the ones that are still cultivated is a further step in their evolution in order to preserve their agricultural significance. Adapting historical landraces to present agricultural conditions using cutting-edge breeding technology represents a challenging opportunity to use them in a modern sustainable agriculture, as an immediate return on the investment is highly unlikely. Consequently, we propose a more inclusive definition of landraces, namely that they consist of cultivated varieties that have evolved and may continue evolving, using conventional or modern breeding techniques, in traditional or new agricultural environments within a defined ecogeographical area and under the influence of the local human culture. This includes adaptation of landraces to new management systems and the unconscious or conscious selection made by farmers or breeders using available technology. In this respect, a mixed selection system might be established in which farmers and other social agents develop evolved landraces from the variability generated by public entities.This work has been partially funded by the European Union's Horizon 2020 research and innovation program under grant agreements no. 634651 (TRADITOM) and no. 677379 (G2PSOL).Casañas Artigas, F.; Simo, J.; Casals, J.; Prohens Tomás, J. (2017). Toward an Evolved Concept of Landrace. 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Biological Control Efforts of Water hyacinth (Eichhornia crassipes (Mart.) Solm) on Kainji Lake, Nigeria
Biological control of water hyacinth (Eichhornia crassipes (Mart.) Solm) was monitored on Kainji Lake between 1995 and 1999. The two most important host specific natural enemies of water hyacinth (Neochetina eichhorniae and N. bruchi) were used and impacts of the weevils on water hyacinth were monitored on tri-monthly basis. The manual control initiated by the National Institute for Freshwater Fisheries Research (NIFFR) encouraged the fishermen to physically remove water hyacinth from their shores and open water. The lake hydrology, most especially during the drawdown period when the water volume is reduced tremendously, allows water hyacinth plants to be stranded by the bank of the lake thereby leading to massive destruction of the weed population and consequently the weevils population stability. The floristic composition of macrophyte intimately mixed with the water hyacinth was also monitored during the low and high water regimes. Among the prominent plant species found with water hyacinth included Echinochloa stagnina, Mimosa pigra, Polygonium senegalensis Polygonium lanigarium. Sesbania dalzelli, and Vosia cuspidata were found competing with the much favoured Echinochloa spp which serves as forage to livestock around the lake; However, no incidence of weevil attack was observed on any of the vegetation mixed with water hyacinth. Keywords: Biocontol, Kainji Lake, Water hyacinth, Weevils
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