2,613 research outputs found
Auto-conceito de competência: diferenças entre cursos de carácter geral e profissional no ensino secundário português
[Resumo] o Ensino Secundário Portugues oferece um vasto leque de modalidades de formação com
objectivos distintos, estando a escolha por uma delas relacionada com as oportunidades sócio-económicas, interesses, projectos, aspirações/expectativas pessoais, escolares e/ou profissionais dos
alunos, bem como com as percepções que estes formam acerca das suas próprias capacidades e
competencias. Neste quadro, considerando o auto-conceito de competencia como a percepção acerca das capacidades para lidar de forma eficaz com o ambiente, nomeadamente do ponto de vista cognitivo, social e de criatividade, desenvolvemos um estudo diferencial com 403 alunos que frequentam duas vias/modalidades distintas do Ensino Secundário - Cursos de Carácter Geral e Cursos Profissionais
-, utilizando a Escala de Auto-Conceito de Competencia de Raty e Snellman (1992), adaptada ao
contexto portugues por Faria, Lima Santos e Bessa (1996).
Os resultados mostram que o auto-conceito de competencia se diferencia em função do género,
do nível de escolaridade e do nível sócio-económico, corroborando outros estudos portugueses. As
diferenças em função da via/modalidade de ensino favorecem os alunos que frequentam Cursos de
Carácter Geral, facto este que pode estar relacionado com os diferentes objectivos e actividades
valorizados por cada via/modalidade, o que sugere a promoção de um desenvolvimento diferenciado
da percepção de competencia pessoa
An assessment of environmental and toxicological risk to pesticide exposure based on a case-based approach to computing
Pesticide environmental fate and toxicity depends on its physical and chemical features, the soil composition, soil adsorption, as well as residues that may be found in different soil slots. Indeed, pesticide degradation in soil may be influenced by either biotic or abiotic factors. In addition, the toxicity of pesticides for living organisms depends on their adsorption, distribution, biotransformation, dissemination of metabolites together with interaction with cellular macromolecules and excretion. Biotransformation may result in the formation of less toxic and/or more toxic metabolites, while other processes determine the balance between toxic and a nontoxic upcoming. Aggregate exposure and risk assessment involve multiple pathways and routes, including the potential for pesticide residues in food and drinking water, in addition to residues from pesticide use in residential and non-occupational environments. Therefore, this work will focus on the development of a decision support system to assess the environmental and toxicological risk to pesticide exposure, built on top of a Logic Programming approach to Knowledge Representation and Reasoning, complemented with a Case Based attitude to computing. The proposed solution is unique in itself, once it caters for the explicit treatment of incomplete, unknown, or even self-contradictory information, either in terms of a qualitative or quantitative setting.This work has been supported by COMPETE: POCI-01-0145-FEDER-007043 and FCT – Fundação para a Ciência e Tecnologia within the Project Scope: UID/CEC/00319/2013.info:eu-repo/semantics/publishedVersio
Model simplification of signal transduction pathway networks via a hybrid inference strategy
A full-scale mathematical model of cellular networks normally involves a large number of variables and parameters. How to effectively develop manageable and reliable models is crucial for effective computation, analysis and design of such systems. The aim of model simplification is to eliminate parts of a model that are unimportant for the properties of interest. In this work, a model reduction strategy via hybrid inference is proposed for signal pathway networks. It integrates multiple techniques including conservation analysis, local sensitivity analysis, principal component analysis and flux analysis to identify the reactions and variables that can be considered to be eliminated from the full-scale model. Using an I·B-NF-·B signalling pathway model as an example, simulation analysis demonstrates that the simplified model quantitatively predicts the dynamic behaviours of the network
Application of MALDI-TOF MS for requalification of a Candida clinical isolates culture collection
Microbial culture collections underpin biotechnology applications and are important resources for clinical microbiology by supplying reference strains and/or performing microbial identifications as a service. Proteomic profiles by MALDI-TOF MS have been used for Candida spp. identification in clinical laboratories and demonstrated to be a fast and reliable technique for the routine identification of pathogenic yeasts. The main aim of this study was to apply MALDI-TOF MS combined with classical phenotypic and molecular approaches to identify Candida clinical isolates preserved from 1 up to 52 years in a Brazilian culture collection and assess its value for the identification of yeasts preserved in this type of collections. Forty Candida spp. clinical isolates were identified by morphological and biochemical analyses. Identifications were also performed by the new proteomic approach based on MALDI-TOF MS. Results demonstrated 15% discordance when compared with morphological and biochemical analyses. Discordant isolates were analysed by ITS sequencing, which confirmed the MALDI-TOF MS identifications and these strains were renamed in the culture collection catalogue. In conclusion, proteomic profiles by MALDI-TOF MS represents a rapid and reliable method for identifying clinical Candida species preserved in culture collections and may present clear benefits when compared with the performance of existing daily routine methods applied at health centres and hospitals.Research leading to these results received partial funding from the European Community's Seventh Framework Program (FP7, 2007-2013), Research Infrastructures Action, under grant agreement No. FP7-228310 (EMbaRC project). Thanks are also due to Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES, Brazil) for funding suppor
Gla-rich protein (GRP) as an early and novel marker of vascular calcification and kidney dysfunction in diabetic patients with CKD: a pilot cross-sectional study
Vascular calcification (VC) is one of the strongest predictors of cardiovascular risk in chronic kidney disease (CKD) patients. New diagnostic/prognostic tools are required for early detection of VC allowing interventional strategies. Gla-rich protein (GRP) is a cardiovascular calcification inhibitor, whose clinical utility is here highlighted. The present study explores, for the first time, correlations between levels of GRP in serum with CKD developmental stage, mineral metabolism markers, VC and pulse pressure (PP), in a cohort of 80 diabetic patients with mild to moderate CKD (stages 2-4). Spearman's correlation analysis revealed a positive association of GRP serum levels with estimated glomerular filtration rate (eGFR) and α-Klotho, while a negative correlation with phosphate (P), fibroblast growth factor 23 (FGF-23), vascular calcification score (VCS), PP, calcium (x) phosphate (CaxP) and interleukin 6 (IL-6). Serum GRP levels were found to progressively decrease from stage 2 to stage 4 CKD. Multivariate analysis identified low levels of eGFR and GRP, and high levels of FGF-23 associated with both the VCS and PP. These results indicate an association between GRP, renal dysfunction and CKD-mineral and bone disorder. The relationship between low levels of GRP and vascular calcifications suggests a future, potential utility for GRP as an early marker of vascular damage in CKD.Portuguese Society of Nephrology (SPN) ; Portuguese national funds from FCT-Foundation for Science and Technology through the transitional provision
DL57/2016/CP1361/CT0006
UIDB/04326/2020info:eu-repo/semantics/publishedVersio
Sildenafil improves right ventricular function in a cardiac transplant recipient
We report the case of a male patient who underwent orthotopic cardiac transplantation. A marginal donor was used, because the recipient's clinical condition was critical. He experienced cardiogenic shock due to right ventricular dysfunction secondary to pulmonary hypertension associated with vasoplegia. After the introduction of sildenafil, the patient recovered hemodynamically, his pulmonary vascular resistance decreased, the vasoactive drugs were withdrawn, and his right ventricular function improved.Relatamos caso de um paciente submetido a transplante cardíaco ortotópico, onde se utilizou um doador marginal pela piora clínica do receptor, que apresentava choque cardiogênico por disfunção de ventrículo direito secundária a hipertensão pulmonar associado à vasoplegia. Obtivemos recuperação hemodinâmica do paciente, com redução da resistência vascular pulmonar, retirada de drogas vasoativas e recuperação da função do ventrículo direito após a introdução de sildenafil.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUNIFESP, EPMSciEL
Electrospun nanosized cellulose fibers using ionic liquids at room temperature
Aiming at replacing the noxious solvents commonly employed, ionic-liquid-based solvents have been recently explored as novel non-volatile and non-flammable media for the electrospinning of polymers. In this work, nanosized and biodegradable cellulose fibers were obtained by electrospinning at room temperature using a pure ionic liquid or a binary mixture of two selected ionic liquids. The electrospinning of 8 wt% cellulose in 1-ethyl-3-methylimidazolium acetate medium (a low viscosity and room temperature ionic liquid capable of efficiently dissolving cellulose) showed to produce electrospun fibers with average diameters within (470 ± 110) nm. With the goal of tailoring the surface tension of the spinning dope, a surface active ionic liquid was further added in a 0.10 : 0.90 mole fraction ratio. Electrospun cellulose fibers from the binary mixture composed of 1-ethyl-3-methylimidazolium acetate and 1-decyl-3-methylimidazolium chloride ionic liquids presented average diameters within (120 ± 55) nm. Scanning electron microscopy, X-ray diffraction analysis, nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric assays were used as core methods to evaluate the structural integrity, morphology and crystallinity of the raw, electrospun, and regenerated samples of cellulose. Moreover, the photoluminescence spectra of both raw and electrospun fibers were acquired, and compared, indicating that the cellulose emitting centers are not affected by the dissolution of cellulose in ionic liquids. Finally, the use of non-volatile solvents in electrospinning coupled to a water coagulation bath allows the recovery of the ionic fluid, and represents a step forward into the search of environmentally friendly alternatives to the conventional approaches
Cytometric evaluation of abdominal subcutaneous adipocytes after percutaneous CO2 infiltration
OBJETIVO: Avaliar os efeitos da infiltração de dióxido de carbono em adipócitos presentes na parede abdominal. MÉTODOS: Quinze voluntárias foram submetidas a sessões de infusão de CO2 durante três semanas consecutivas (duas sessões por semana com intervalos de dois a três dias entre cada sessão). O volume de gás carbônico infundido por sessão, em pontos previamente demarcados, foi sempre calculado com base na superfície da área a ser tratada, com volume infundido fixo de 250 mL/100cm² de superfície tratada. Os pontos de infiltração foram demarcados respeitando-se o limite eqüidistante 2cm entre eles. Em cada ponto se injetou 10mL, por sessão, com fluxo de 80mL/min. Foram colhidos fragmentos de tecido celular subcutâneo da parede abdominal anterior antes e após o tratamento. O número e as alterações histomorfológicas dos adipócitos (diâmetro médio, perímetro, comprimento, largura e número de adipócitos por campos de observação) foram mensurados por citometria computadorizada. Os resultados foram analisados com o teste t de Student pareado, adotando-se nível de significância de 5% (p<0,05). RESULTADOS: Encontrou-se redução significativa no número de adipócitos da parede abdominal e na área, diâmetro, perímetro, comprimento e largura após o uso da hipercapnia (p=0,0001). CONCLUSÃO: A infiltração percutânea de CO2 reduz a população e modifica a morfologia dos adipócitos presentes na parede abdominal anterior.OBJECTIVE: To evaluate the effects of carbon dioxide infusion to abdominal wall adipocytes. METHODS: Fifteen volunteers were subjected to sessions of CO2 infusion for three consecutive weeks (two sessions per week with intervals of two to three days between each). The volume of carbon dioxide infused per session, at points previously marked, was always calculated on the basis of surface area to be treated, with a fixed infused volume of 250 ml/100cm² of treated surface. The infiltration points were marked respecting the limit of 2cm equidistant between them. At each point 10 ml was injected per session, with a flow of 80ml/min. Fragments were collected from subcutaneous tissue of the anterior abdominal wall before and after treatment. The number and histomorphological changes of adipocytes (mean diameter, perimeter, length, width and number of adipocytes per field of observation) were measured by computerized cytometry. The results were analyzed with paired Student t test, adopting a significance level of 5% (p <0.05). RESULTS: There was a significant reduction in the number of adipocytes in the abdominal wall, as well as the area, diameter, perimeter, length and width of the adipocytes, after the infusion of CO2 (p = 0.0001). CONCLUSION: The percutaneous infiltration of CO2 reduces the population of adipocytes of the anterior abdominal wall and modifies their morphology
The house and the garden: socio-economy, demography and agriculture in Quilombola populations of the Ribeira Valley, São Paulo, Brazil
Este estudo tem como objetivos caracterizar o perfil demográfico e socioeconômico de nove comunidades remanescentes de quilombos no vale do Ribeira, estado de São Paulo, e identificar os principais fatores responsáveis pelas mudanças recentes nos seus padrões de subsistência. Desde a formação das primeiras aglomerações de escravos libertos e foragidos no século XVIII, as relações estabelecidas entre estas populações com as cidades próximas e com o mercado regional têm vivenciado momentos de retração e de expansão, adaptando-se e ajustando-se a novas mudanças políticas e socioeconômicas. Nas últimas cinco décadas, o impacto de fatores externos na aceleração das mudanças nos padrões de subsistência locais parece ter tido um aumento significativo. Os resultados mostram que as restrições impostas pela legislação ambiental, os conflitos de terra, a construção de uma rodovia na região, a crescente inserção no mercado regional e a atuação de órgãos governamentais e não-governamentais de desenvolvimento são os principais fatores responsáveis pelas mudanças observadas no sistema agrícola de corte e queima e, conseqüentemente, na organização socioeconômica destas populações.This study aims to characterize the socioeconomic and demographic profile of nine Quilombola populations in the Ribeira Valley, State of São Paulo, and to identify the main factors responsible for the recent changes in their subsistence system. Since the first assemblages of runway and abandoned slaves in the 18th. century, the relations established by these populations with nearby towns and regional market have gone through periods of expansion and retraction, adapting and adjusting to new socioeconomic and political changes. In the last five decades, the impact of external factors on the local subsistence patterns appears to have had a significant increase. Our results show that restrictions imposed by environmental laws, conflict over land, the construction of a major road in the region, the growing insertion into a market economy, and the intervention of governmental and non-governmental development agencies are the main factors behind the changes observed in the subsistence system and, consequently, in the socioeconomic organization of these populations
Stability analysis of the Randall-Sundrum braneworld in presence of bulk scalar
The stability problem of Randall-Sundrum braneworld is readdressed in the
light of stabilizing bulk scalar fields. It is shown that in such scenario the
instability persists because of back-reaction even when an arbitrary potential
is introduced for a canonical scalar field in the bulk. It is further shown
that a bulk scalar field can indeed stabilize the braneworld when it has a
tachyon-like action. The full back-reacted metric in such model is derived and
a proper resolution of the hierarchy problem (for which the Randall Sundrum
scenario was originally proposed) is found to exist by suitable adjustments of
the parameters of the scalar potential.Comment: 4 pages, No figures, Revte
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