O impacto do peso no autoconceito de jovens com excesso de peso e obesidade.

Mestrado em Ciências da Educação, especialidade em Educação para a SaúdeAbordou-se a questão dos aspectos psicológicos relacionados com o autoconceito em jovens com excesso de peso e obesidade. Avaliou-se o IMC, o autoconceito, a autoestima e o índice de atividade física numa amostra de jovens com idades entre os 12 e os 18 anos (n=106), através da Escala de Autoconceito para Adolescentes (Harter, 1988) e o Questionário de Atividade Física (Mota et al, 2002). As raparigas apresentaram valores significativamente inferiores na perceção de competência atlética (média ± dp: 2,8 ± 0,7 vrs 2,3 ± 0,7, respetivamente para rapazes e raparigas: p=0,00) e na importância atribuída a este domínio (média ± dp: 3,2 ± 0,8 vrs 2,6 ± 0,7, respetivamente para rapazes e raparigas: p=0,00), mas não nos restantes domínios do autoconceito e na autoestima global. Relativamente à prática de AF, constatou-se que os jovens da amostra possuíam um índice de intensidade moderada (12,7 ± 3,8), sendo que as raparigas apresentaram valores significativamente inferiores (média ± dp: 13,7 ± 3,4 vrs 11,2 ± 3,9, respetivamente para rapazes e raparigas: p=0,00). Encontraram-se associações entre o IMC e as variáveis competência atlética e aparência física, atração romântica e importância atribuída à competência escolar. Os resultados indicam que o IMC influencia alguns domínios do autoconceito, embora não se tenham observado diferenças entre jovens com IMC distinto em nenhuma das variávies estudadas, corroborando algumas das evidências encontradas na literatura

The influence of the blood pressure on the venous cerebral flow measured by magnetic susceptibility (SWI) technique

Susceptibility Weighted Image (SWI) is a Magnetic Resonance Imaging (MRI) technique that combines high spatial resolution and sensitivity to provide magnetic susceptibility differences between tissues. It is extremely sensitive to venous blood due to its iron content of deoxyhemoglobin. The aim of this study was to evaluate, through the SWI technique, the differences in cerebral venous vasculature according to the variation of blood pressure values. 20 subjects divided in two groups (10 hypertensive and 10 normotensive patients) underwent a MRI system with a Siemens® scanner model Avanto of 1.5T using a synergy head coil (4 channels). The obtained sequences were T1w, T2w-FLAIR, T2* and SWI. The value of Contrast-to-Noise Ratio (CNR) was assessed in MinIP (Minimum Intensity Projection) and Magnitude images, through drawing free hand ROIs in venous structures: Superior Sagittal Sinus (SSS) Internal Cerebral Vein (ICV) and Sinus Confluence (SC). The obtained values were presented in descriptive statistics-quartiles and extremes diagrams. The results were compared between groups. CNR shown higher values for normotensive group in MinIP (108.89 ± 6.907) to ICV; (238.73 ± 18.556) to SC and (239.384 ± 52.303) to SSS. These values are bigger than images from Hypertensive group about 46 a.u. in average. Comparing the results of Magnitude and MinIP images, there were obtained lower CNR values for the hypertensive group. There were differences in the CNR values between both groups, being these values more expressive in the large vessels-SSS and SC. The SWI is a potential technique to evaluate and characterize the blood pressure variation in the studied vessels adding a physiological perspective to MRI and giving a new approach to the radiological vascular studies

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved