915 research outputs found
Characterisation of polyphenols by HPLC-PAD-ESI/MS and antioxidant activity in Equisetum telmateia
The antioxidant activity of an aqueous extract (infusion) and respective ethyl acetate fraction of Equisetum telmateia Ehrh. (Equisetaceae), a plant used in traditional medicine for its anti-inflammatory and diuretic properties, has been evaluated by DPPH, TEAC and TBARS assays. A high and significant antioxidant activity was detected in the ethyl acetate fraction. Analysis of the aqueous extract and the ethyl acetate fraction by HPLC-PAD-ESI/MS allowed the identification of the major phenolic compounds as flavan-3-ol, kaempferol and phenolic acid derivatives. Among the flavan-3-ols, A-type proanthocyanidins and afzelechin derivatives were detected as well as the more common B-type procyanidins, B2 and C1, whose identification was further confirmed by HPLC using detection involving chemical reaction with p-dimethylamino-cinnamaldehyde. The results suggest that the anti-inflammatory activity of E. telmateia could be due, at least in part, to the presence of compounds with antioxidant activity. Copyright © 2005 John Wiley & Sons, Ltd
Otimização da técnica FISH para a sua aplicação na deteção de microrganismos que colonizam os bens patrimoniais
Os bens patrimoniais constituem uma parte importante da herança cultural e estão continuamente sujeitos a processos que favorecem a sua deterioração. São múltiplos os fatores que contribuem no processo (pH, temperatura, humidade, entre outros) e os microrganismos (estirpe bacteriana, estirpe de leveduras, fungos, entre outros) têm um papel importante. Deste modo é crucial compreender o papel destes agentes no processo de deterioração, identificando-os, para formular estratégias adequadas para a conservação e salvaguarda do património cultural. E por isso necessário desenvolver e/ou adaptar as metodologias e técnicas que permitam responder a estas necessidades. O objetivo deste trabalho é desenvolver um protocolo inovador que permita reduzir os tempos necessários para detetar e analisar estirpe bacteriana e estirpe de leveduras aplicando a técnica de Hibridação In Situ Fluorescente (FISH). Para tal fim, foram testados vários métodos de hibridação, alguns deles baseados na aplicação de microondas, em células fixadas quimicamente, através da técnica FISH. Uma vez determinado o melhor método de hibridação para cada microrganismo, estes foram combinados junto com a fixação com microondas de modo a tentar reduzir os tempos até o máximo possível. Da análise, tanto quantitativa como qualitativa dos resultados obtidos, poderá vir desenvolver-se um protocolo rápido, económico com aplicação na análise dos bens patrimoniais.Este trabalho é financiado por Fundos Nacionais através da FCT –Fundação
para a Ciência e a Tecnologia no âmbito do projeto “MICROTECH-ART –
Desenvolvimento de uma Ferramenta Analítica para deteção de Microrganismos
que proliferam no Património Cultural” (PTDC/BBB-IMG/0046/2014)
Adaptación a la docencia de materiales de feedback como soporte a la adquisición de competencias en el ámbito de las bases de datos
Memoria ID-0237. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2014-2015
Hybrid Multiagent System for Automatic Object Learning Classification
The rapid evolution within the context of e-learning is closely linked to international efforts on the standardization of learning object metadata, which provides learners in a web-based educational system with ubiquitous access to multiple distributed repositories. This article presents a hybrid agent-based architecture that enables the recovery of learning objects tagged in Learning Object Metadata (LOM) and provides individualized help with selecting learning materials to make the most suitable choice among many alternatives
Understanding social and environmental hazards in urban areas: an analysis from Barranquilla, Colombia
The present research aims to understand the challenges faced by a Colombian city in the context of multidimensional risk scenarios, given the existing demographic and socio-economic conditions and local perspectives and perceptions regarding socio-environmental risks. The research was undertaken in the city of Barranquilla, northern Colombia. A survey was designed to analyze (1) the general socio-economic and vulnerability conditions of a communities’ sample, (2) information related to hazards and disaster risk in their neighbourhoods, and (3) information on actions to mitigate risk. Three hundred and ninety-one people were surveyed. Likert scale and Pearson's Chi-square test and descriptive, inferential statistical methods, regression models, and the Mann–Whitney U test were used to process the results. Respondents lived, in general, under precarious socio-economic conditions (such as low income or lack of infrastructure and others). Given socio-environmental constraints, the research revealed that hazards such as urban stream flooding and robbery were the most negatively associated with the respondent’s quality of life. Regarding the actions to avoid losses, 84% of respondents had not implemented any preventive action. Respondents also have low awareness of the need to implement risk prevention actions. Social risks and the configuration of anthropic hazards stand out as principal centres for concern
Multiple hazards and governance model in the Barranquilla Metropolitan Area, Colombia
The Barranquilla Metropolitan Area is exposed and often vulnerable to various natural and anthropogenic hazards. The paper’s main objective is to identify the level of understanding that local and regional institutions have of such a multi-hazard scenario, as well as the effectiveness of governance arrangements in minimizing impacts. Research employed a questionnaire applied to 115 stakeholders from government and a survey of 391 households from four communities in the study area. Four focus groups were held during the update of the Barranquilla Development Plan 2020–2023. The results allowed the identification of an updated set of hazards and the levels of government response capacity. The overall level of capacity and effectiveness of local government to respond to hazards was classified as regular. Seventy-seven percent of epistemic ‘experts considered that the institutions responsible for risk management did not undertake sufficient analysis for identifying and managing multiple hazards. Finally, the research team developed a new model of risk management
Online measurements of real-time cytotoxic responses induced by multi-component matrices, such as natural products, through electric-cell substrate impedance sensing (ECIS).
Natural products are complex matrices of compounds that are prone to interfere with the label-dependent methods that are typically used for cytotoxicity screenings. Here, we developed a label-free Electric Cell-substrate Impedance Sensing (ECIS)-based cytotoxicity assay that can be applied in the assessment of the cytotoxicity of natural extracts. The conditions to measure the impedance using ECIS were first optimized in mice immortalized hypothalamic neurons GT1-7 cells. The performance of four natural extracts when tested using three conventional cytotoxicity assays in GT1-7 cells, was studied. Betula pendula (silver birch tree) was found to interfere with all of the cytotoxicity assays in which labels were applied. The silver birch extract was also proven to be cytotoxic and, thus, served as a proof-of-concept for the use of ECIS. The extract was fractionated and the ECIS method permitted the distinction of specific kinetic patterns of cytotoxicity on the fractions as well as the extract's pure constituents. This study offers evidence that ECIS is an excellent tool for real-time monitoring of the cytotoxicity of complex extracts that are difficult to work with using conventional (label-based) assays. Altogether, it offers a very suitable cytotoxicity-screening assay making the work with natural products less challenging within the drug discovery workflow.Peer reviewe
Estudio de evaluación del impacto emocional en modelos de docencia presencial y virtual en el alumnado a través de técnicas de neurociencia
Memoria ID-0091. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2016-2017
Percepção de risco do uso nocivo do álcool e suas consequências em adolescentes
Alcoholism is the most important drug addiction of our time. Teaching adolescents about alcoholism and its unfavorable consequences, is a way to promote the perception of risk and contribute to the prevention of this disease. With the objective of modifying the perception of the risk of alcoholism and its consequences, a study of quasi-experimental educational intervention was conducted in adolescents of the Jesús Menéndez de Bayamo, Granma, 2015-2017. We worked with a sample of 180 adolescents from 15 to 19 years of age. Variables studied: independent (educational intervention) and dependent (perception of risk of alcoholism and its consequences for the organism, the family and social environment). The research was carried out in four stages: diagnosis, design and validation, application and evaluation. Theoretical, empirical and statistical methods were used. As summary measures, the absolute and relative frequencies were used, and the Wilcoxon signed-rank test was used to determine the existence of statistically significant differences before and after the intervention, with a level of significance of 5%, calculated with the aid of the professional statistical program SPSS 22.0 for Windows. Initially, the low level of knowledge (55.6%), inadequate beliefs about harmful consumption of alcohol (86.7%) and low perception of risk (55.6%) predominated. After the intervention, most adolescents had improved knowledge, beliefs and risk perception, with statistically significant differences that showed that the results were due to educational work and not to chance.El alcoholismo constituye la más relevante toxicomanía de nuestros días. Enseñar a los adolescentes acerca del alcoholismo y sus desfavorables consecuencias, es una manera de favorecer la percepción del riesgo y contribuir a la prevención de esta enfermedad. Con el objetivo de modificar la percepción del riesgo de alcoholismo y sus consecuencias, se realizó un estudio de intervención educativa cuasi experimental en adolescentes del Reparto Jesús Menéndez de Bayamo, Granma, 2015-2017. Se trabajó con una muestra de 180 adolescentes de 15 a 19 años de edad. Variables estudiadas: independiente (intervención educativa) y dependiente (percepción de riesgo de alcoholismo y sus consecuencias para el organismo, el ambiente familiar y social). La investigación se realizó en cuatro etapas: diagnóstico, diseño y validación, aplicación y evaluación. Se emplearon métodos teóricos, empíricos y estadísticos. Como medidas de resumen se utilizaron las frecuencias absolutas y relativas, y la prueba de los rangos con signo de Wilcoxon para determinar la existencia de diferencias estadísticamente significativas antes y después de la Intervención, con un nivel de significación del 5%, calculado con el auxilio del programa estadístico profesional SPSS 22.0 para Windows. Inicialmente, predominó el bajo nivel de conocimiento (55,6%), las creencias inadecuadas sobre consumo nocivo del alcohol (86,7%) y baja percepción de riesgo (55,6%). Después de la intervención, la mayoría de los adolescentes había mejorado los conocimientos, las creencias y la percepción del riesgo, con diferencias estadísticamente significativas que demostraron que los resultados se debieron a la labor educativa y no al azar.O alcoolismo é o mais importante vício em drogas do nosso tempo. Ensinar adolescentes sobre o alcoolismo e suas consequências desfavoráveis, é uma forma de promover a percepção de risco e contribuir para a prevenção desta doença. Com o objetivo de modificar a percepção do risco do alcoolismo e suas conseqüências, realizou-se um estudo de intervenção educativa quase experimental em adolescentes do Jesús Menéndez de Bayamo, Granma, 2015-2017. Trabalhamos com uma amostra de 180 adolescentes de 15 a 19 anos de idade. Variáveis estudadas: independente (intervenção educativa) e dependente (percepção do risco de alcoolismo e suas consequências para o organismo, a família e o meio social). A pesquisa foi realizada em quatro etapas: diagnóstico, desenho e validação, aplicação e avaliação. Métodos teóricos, empíricos e estatísticos foram utilizados. Como medidas de resumo, foram utilizadas as frequências absolutas e relativas, e o teste dos postos sinalizados de Wilcoxon foi utilizado para determinar a existência de diferenças estatisticamente significativas antes e após a intervenção, com um nível de significância de 5%, calculado com o auxílio. do programa estatístico profissional SPSS 22.0 for Windows. Inicialmente, predominou o baixo nível de conhecimento (55,6%), as crenças inadequadas sobre o consumo prejudicial de álcool (86,7%) e a baixa percepção de risco (55,6%). Após a intervenção, a maioria dos adolescentes melhorou o conhecimento, as crenças e a percepção de risco, com diferenças estatisticamente significantes que mostraram que os resultados foram devidos ao trabalho educativo e não ao acaso
Nutritional status of children with oncological diseases in the pediatric hospital of Pinar del Río
Introduction: malnutrition and weight loss is a frequent problem in cancer patients, affecting the prognosis, prolonging hospital stays, increasing costs and affecting quality of life and survival.
Objective: to characterize the nutritional status of children with oncological diseases admitted to the oncohematology service at Pepe Portilla Provincial Pediatric Teaching Hospital in Pinar del Río during the years 2013 and 2014.
Method: a descriptive and cross sectional study was carried out. The target group was comprised of 53 children admitted the oncohematology service. The information obtained was processed using descriptive statistics methods and the computer program by the EPINFO statistical software.
Results: 34% of the patients were classified as malnourished, 83.3% with decreased albumin, with leukemia being the most frequent diagnosis, with 27.8%.
Conclusions: a high frequency of malnutrition was found in patients with oncological diseases and a close relationship between the classifications based on anthropometric, biochemical and immunological indicators
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