4 resultados para Exposure intensity

em Greenwich Academic Literature Archive - UK


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In the present study, we assessed the effects of exercise intensity on salivary immunoglobulin A (s-IgA) and salivary lysozyme (s-Lys) and examined how these responses were associated with salivary markers of adrenal activation. Using a randomized design, 10 healthy active men participated in three experimental cycling trials: 50% maximal oxygen uptake (VO2max), 75%VO2max, and an incremental test to exhaustion. The durations of the trials were the same as for a preliminary incremental test to exhaustion (22.3 min, sx = 0.8). Timed, unstimulated saliva samples were collected before exercise, immediately after exercise, and 1 h after exercise. In the incremental exhaustion trial, the secretion rates of both s-IgA and s-Lys were increased. An increase in s-Lys secretion rate was also observed at 75%VO2max. No significant changes in saliva flow rate were observed in any trial. Cycling at 75%VOmax and to exhaustion increased the secretion of alpha-amylase and chromogranin A immediately after exercise; higher cortisol values at 75%VO2max and in the incremental exhaustion trial compared with 50%VO2max were observed 1 h immediately after exercise only. These findings suggest that short-duration, high-intensity exercise increases the secretion rate of s-IgA and s-Lys despite no change in the saliva flow rate. These effects appear to be associated with changes in sympathetic activity and not the hypothalamic - pituitary - adrenal axis.

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The aim of the present review was to perform a systematic in-depth review of the best evidence from controlled trial studies that have investigated the effects of nutrition, diet and dietary change on learning, education and performance in school-aged children (4-18 years) from the UK and other developed countries. The twenty-nine studies identified for the review examined the effects of breakfast consumption, sugar intake, fish oil and vitamin supplementation and 'good diets'. In summary, the studies included in the present review suggest there is insufficient evidence to identify any effect of nutrition, diet and dietary change on learning, education or performance of school-aged children from the developed world. However, there is emerging evidence for the effects of certain fatty acids which appear to be a function of dose and time. Further research is required in settings of relevance to the UK and must be of high quality, representative of all populations, undertaken for longer durations and use universal validated measures of educational attainment. However, challenges in terms of interpreting the results of such studies within the context of factors such as family and community context, poverty, disease and the rate of individual maturation and neurodevelopment will remain. Whilst the importance of diet in educational attainment remains under investigation, the evidence for promotion of lower-fat, -salt and -sugar diets, high in fruits, vegetables and complex carbohydrates, as well as promotion of physical activity remains unequivocal in terms of health outcomes for all schoolchildren.

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Clinical placement experience has a key role to play in the socialisation and preparation of future members of the nursing profession. Aggression experienced by healthcare workers is currently receiving considerable attention and student nurses have been identified as a group vulnerable to experiencing workplace abuse (Little 1999). The primary aim of the study is to gain a greater understanding of the nature, severity, frequency and sources of verbal abuse experienced by student nurses in health care settings in the south east of England, using as a definition, “the use of inappropriate words… causing distress” (Department of Health 2003). A convenience sample of 156 third year student nurses of all four branches of one preregistration nursing programme in the south east of England was studied with questionnaires distributed retrospectively; 11 4 student nurses returned the questionnaires equating to a response rate of 73%. Results 46% of respondents reported experiencing verbal abuse, 39% had witnessed other students experiencing verbal abuse and 61% reported that they were aware of other students experiencing verbal abuse. Students reported experiencing threats to kill, racial abuse, sexually orientated verbal abuse and bullying while gaining placement experience. Student nurses are a high risk group for experiencing verbal abuse whilst gaining placement experience.In the literature, mental health and learningdisability settings are viewed as high risk areasfor experiencing aggression (Beech and Leather 2003); this study suggests that student nurses experience verbal abuse in a variety of settings and verbal abuse may be more prevalent on general medical and surgical wards than previously expected.