509 research outputs found
Implementación de cinco prácticas de laboratorio para el manual de Fisicoquímica en las áreas de termodinámica y cinética química de la Universidad Tecnológica de Pereira
Para mejorar el proceso de aprendizaje de los estudiantes de Tecnología Química y Química Industrial, la Escuela de Química de la Universidad Tecnológica de Pereira adquirió mediante el proyecto PARCE (Proyecto para la Adquisición, Reposición y Compra de Equipos) dos equipos para el laboratorio de Fisicoquímica I (TQ 562) y tres para el laboratorio de Fisicoquímica II (QI 762) con el fin de implementar nuevos montajes y renovar algunos existentes. La realización de este trabajo de grado tiene como objetivo principal el ensayo y la adecuación de estos montajes en los laboratorios, al igual que la realización del manual de procedimientos indicando las recomendaciones necesarias para obtener unos resultados confiables
Efeitos das variações de PH, temperatura e nutrientes na ecofisiologia de Lithothamnion crspatum Hauck (Corallinales, Rhodophyta) e Sonderophycus capensis (Montagne) M.J. Wynne (Peyssonneliales, Rhodophyta): subsídios para o entendimento das mudanças climáticas
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-Graduação em Biologia de Fungos, Algas e Plantas, Florianópolis, 2013.No presente trabalho se avaliou a interação das variações do pH, temperatura e nutrientes a partir de níveis locais atuais destes fatores, no desempenho fisiológico de duas espécies de algas calcárias com diferenças de distribuição e afinidades ecofisiológicas. Sonderophycus capensis é uma espécie típica de ambientes temperados frios, enquanto que Lithothamnion crispatum é uma espécie de ambientes tropicais. A partir de experimentos feitos em microcosmo, a temperatura se mostrou o principal fator que levou às alterações da fisiologia dessas algas. As taxas de transporte de elétrons (ETR) diminuíram drasticamente nos tratamentos que se encontravam em elevada temperatura nas duas espécies. Adicionalmente, no tratamento que se encontrava em temperatura elevada, o baixo pH (7,2) manteve a ETR constante, atuando o pH de forma aditiva e antagônica com a temperatura. Com relação à calcificação, o pH baixo (7,2)/injeção de CO2 atuou de forma aditiva, estimulando a descalcificação na mesma forma nas duas espécies. Por outro lado, a elevada temperatura beneficiou a calcificação, chegando até 51% de calcificação em condições de pH controle. A interação também foi observada entre a temperatura e o pH, beneficiando levemente a calcificação. Em outro sentido, foram tomada amostras de água e analisadas, com o fim de observar se existiam mudanças nas espécies de carbonato. Desta forma, a concentração do íon carbonato (CO3 -2) foi menor nos tratamentos com baixo pH, assim como também as saturações de calcita e aragonita. Na maior parte das análises feitas nas duas espécies, os fatores mais importantes foram temperatura e pH, atuando de forma aditiva ou sinérgica. Por sua vez, os nutrientes não tiveram grande influencia na fisiologia. Apesar das diferenças na distribuição das duas espécies, não se observaram grandes diferenças nas respostas fisiológicas delas ao ser submetidas a variações de temperatura, pH e nutrientes. Em futuros experimentos, a aplicação dos fatores já mencionados por maiores períodos de tempo poderia contribuir para entender de melhor forma as implicâncias na ecofisiologia das espécies calcificadas.Abstract : In the present work it is evaluated the interaction effect of changes in pH, temperature and nutrients with current local levels each one of factors on the physiological performance of two species of calcareous algae with differences of distribution and eco physiological affinities. Sonderophycus capensis represents a group of species typical of temperate cold environments, whereas Lithothamnion crispatum are species typical of tropical environments. From the analysis in microcosm, the temperature was seen to be main factor driving the alterations on the physiology of both models. ETR quickly decreased when it was in high temperature. Furthermore, a low pH (7,2) also acted in an additive and antagonistic way, increasing the ETR in the treatments at elevated temperature. Concerning the calcification, the injection of CO2 and the low pH modified the calcification percentages, being lower in those treatments kept at low pH in both species. Nevertheless, the temperature favored calcification, being up to 51% higher in pH controlled conditions. Interaction on the calcification was also observed between temperature and pH, slightly increasing the calcification at elevated temperatures. The effects of decreasing pH were also observed on the chemistry of water. For it, the concentration of carbonate ions (CO3-2) was lower in those treatments at low pH. The saturation values of calcite and aragonite were also lower at low pH. In most of the analyses for both species the main driving factors were the temperature and the pH, acting in a synergetic or additive way in most of the cases. Nutrients did not have a big influence on the physiology. In spite of the differences on distribution of both species, no differences in physiological response were observed under the applied stresses. Future experiments conducted for longer periods of time could aid to better understand the eco physiological implicancies on these calcareous species
Teachers’ Identities in Rural Areas From Chile
The research study presented in this article has attempted to generate deep and first-source knowledge on how the identity of teachers who practice their profession in the rural context is forged and configured. The study was carried out in two rural communes in the Ñuble Region.
Through a mixed study, with qualitative predominance, it was possible to investigate the perceptions of a sample of in-service teachers, at different stages of their careers. The study findings show that the identity of the rural teacher is configured by various characteristics, particularly relevant to the rural educational context of Ñuble, but which are equally transferable to other educational realities in rural communes in Chile. The study has revealed that the rural teacher is perceived as a professional with a high degree of vocation and motivation for his/her work, characterized by a high level of professionalism, who exercises multiple roles, establishes close relationships with his/her educational communities and commonly works in challenging conditions due to scarcity of resources available to carry out his/her work in favorable conditions
Influence of dietary condition on the ratio of the compounds emitted by larvae Chilecomadia valdiviana (Lepidoptera: Cossidae)
Chilecomadia valdiviana (Lepidoptera, Cossidae), locally known as "Gusano del Tebo", is a polyphagous pest that, in its larval stage, feeds on the wood of the host species. C. valdiviana is distributed in the southern region of Chile and Argentina and its larvae mainly attack eucalyptus and fruit trees. Previous research has reported the identification of the volatile compounds produced by this species in its larval stage. In this work, the effects of two dietary conditions on these volatile compounds were described: groups of individuals fed with wood vs. others without food. The results obtained provide empirical evidence that C. valdiviana modulates the emission of the compounds according to the effect of stimulus.Chilecomadia valdiviana (Lepidoptera, Cossidae), locally known as "Gusano del Tebo", is a polyphagous pest that, in its larval stage, feeds on the wood of the host species. C. valdiviana is distributed in the southern region of Chile and Argentina and its larvae mainly attack eucalyptus and fruit trees. Previous research has reported the identification of the volatile compounds produced by this species in its larval stage. In this work, the effects of two dietary conditions on these volatile compounds were described: groups of individuals fed with wood vs. others without food. The results obtained provide empirical evidence that C. valdiviana modulates the emission of the compounds according to the effect of stimulus
Antifragility Predicts the Robustness and Evolvability of Biological Networks through Multi-class Classification with a Convolutional Neural Network
Robustness and evolvability are essential properties to the evolution of
biological networks. To determine if a biological network is robust and/or
evolvable, it is required to compare its functions before and after mutations.
However, this sometimes takes a high computational cost as the network size
grows. Here we develop a predictive method to estimate the robustness and
evolvability of biological networks without an explicit comparison of
functions. We measure antifragility in Boolean network models of biological
systems and use this as the predictor. Antifragility occurs when a system
benefits from external perturbations. By means of the differences of
antifragility between the original and mutated biological networks, we train a
convolutional neural network (CNN) and test it to classify the properties of
robustness and evolvability. We found that our CNN model successfully
classified the properties. Thus, we conclude that our antifragility measure can
be used as a predictor of the robustness and evolvability of biological
networks.Comment: 22 pages, 10 figure
Optimización de empaques aplicando lineamientos de diseño para el ensamble validado en los contextos de empaque, transporte y desempaque
Apoyo familiar en estudiantes del primer año de educación secundaria de la institución educativa privada San Antonio de Padua del distrito de San Juan de Lurigancho
El actual proyecto de investigación, de tipo descriptivo y diseño no experimental posee como finalidad establecer el factor apoyo familiar en estudiantes del primer año de educación secundaria de la IEP San Antonio de Padua del distrito de San Juan de Lurigancho – 2018.
Se implementa una encuesta de Apoyo Familiar tomando como referencia la teoría Coleman (1969). La muestra obtenida en el estudio está compuesta por 53 estudiantes del sexo femenino y masculino, de distintas edades y se empleó un muestreo censalThe current research project, of descriptive and non-experimental design aims to establish the family support factor in students of the first year of secondary education of the San Antonio de Padua IEP in the district of San Juan de Lurigancho - 2018.
A Family Support survey is implemented taking the Coleman theory (1969) as a reference. The sample obtained in the study is composed of 53 female and male students of different ages and a census sampling was use
Estado nutricional y calidad de vida en pacientes con cáncer de mama de la red asistencial La Libertad es Es Salud
Objetivo: Determinar la relación entre el estado nutricional y la calidad de vida en pacientes con cáncer de mama de la Red Asistencial La Libertad Es Salud.
Metodología: Se realizó un estudio correlacional. Muestra fue de 152 pacientes con cáncer de mama de la Red Asistencial La Libertad Es Salud. Se aplicó dos instrumentos; uno de ellos, para medir el estilo de vida de pacientes con cáncer de mama, y otro instrumento para medir la calidad de vida en los mismos pacientes con cáncer de mama.
Resultados: Se observó que hay 38.2% de pacientes que se encuentran moderadamente mal nutrido sin embargo tienen una buena calidad de vida. Y dentro de los pacientes que se encuentran bien nutridos sólo hay un 12.5% de ellos que tienen una buena calidad de vida.
Conclusiones: El presente estudio concluye que existe relación significativa moderada entre el estado nutricional y calidad de vida en pacientes con cáncer de mama de la red asistencial La Libertad Es Salud
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