The acute testosterone,growth hormone,cortisol and interleukin-6 response to 164-km road cycling in a hot environment

This study investigated the acute endocrine responses to a 164-km road cycling event in a hot environment. Thirty-four male experienced cyclists (49.1 ± 8.3 years, 86.8 ± 12.5 kg, 178.1 ± 5.1 cm) participating in a 164-km road cycling event were recruited. Blood samples were collected within 0.3–2.0 h before the start (PRE: ~0500–0700 h) and immediately following the ride (POST). Samples were analysed for testosterone, growth hormone (GH), cortisol and interleukin-6 (IL-6). The temperature and humidity during the event were 35.3 ± 4.9°C and 47.2 ± 14.0%, respectively. Based on the finishing time, results for the fastest (FAST, 305 ± 10 min) and the slowest (SLOW, 467 ± 31 min) quartiles were compared. At POST, testosterone concentration was significantly (P < 0.05) lower (PRE, 20.8 ± 8.6; POST, 18.2 ± 6.7 nmol · L^?1), while GH (PRE, 0.3 ± 0.1; POST, 2.3 ± 0.3 µg · L^?1), cortisol (PRE, 661 ± 165; POST, 1073 ± 260 nmol · L^?1) and IL-6 (PRE, 4.0 ± 3.4; POST, 22.4 ± 15.2 pg · mL^?1) concentrations were significantly higher than those at PRE. At POST, GH and cortisol were significantly higher for the FAST group than for the SLOW group (GH, 3.6 ± 2.0 and 1.0 ± 0.8 µg · L^?1; cortisol, 1187 ± 209 and 867 ± 215 nmol · L^?1). Participation in an ultra-endurance road cycling event in a hot environment induced significant acute changes in concentrations of circulating hormones, with a greater augmentation of GH and cortisol in those completing the ride fastest.     

An analysis of how and why a TAFE course was changed: The implications

The Federal government has indicated that vocational education, especially education that is technically oriented, is essential to Australia’s economic future. The Federal government has also expressed concern at the educational inequalities faced by certain groups in society. The Associate Diploma of Technology (Computing) a cross-accredited course giving access to a university degree, was designed to address both of these concerns. This article examines how the course has been altered and the forces behind these changes. This examination is carried out by exploring different perspectives of the course, such as: the government, TAFE, and the students and the teachers. The resulting evidence suggests that students have taken up the government’s rhetoric; they believe they will be snapped up by industry and gain employment in high technology areas, and think that social issues are a waste of time. The evidence also indicates that the course is being targeted more towards young adults who have failed to get into a university course than towards the original target of women and immigrants.     

Can squirrel monkeys (Saimiri sciureus) plan for the future? Studies of temporal myopia in food choice

In seven experiments, 2 squirrel monkeys were given choices between arrays of food that varied in the quantity offered. In Experiments 1-5, the monkeys were offered choices between quantities of the same food that varied in a 2:1 ratio. The squirrel monkeys failed to show the temporal myopia effect or a decrease in preference for the larger quantity as the absolute number of food items offered increased. Even when given choices of 8 versus 16 peanuts and 10 versus 20 peanuts, both monkeys significantly preferred the larger quantity. An examination of the monkeys' rates of consumption indicated that 20 peanuts were consumed over a 1- to 2-h period, with eating bouts separated by periods of nonconsumption. In Experiments 6A, 6B, and 7, food was either pilfered or replenished 15 min after an initial choice, so that choice of the smaller quantity led to more total food in the long run. These manipulations caused both monkeys to reduce choice of the larger quantity, relative to baseline choice. The results suggest that squirrel monkeys anticipated the future consequences of their choices.     

Networking around The Waterhole and other tales: the importance of relationships among texts for reading and related instruction

This article explores ways in which children's picture books form networks of relationships, and their implications for readers and classroom teachers. In this exploration, reading is seen to involve making connections within and beyond the text at hand. These connections, evoked differently across readers, shape readers' interpretations of text. Many possible meanings may arise from just one text, reinforcing the idea that no single correct meaning resides in a text. This article demonstrates tools for exploring textual connections with readers, and the value of such explorations for opening‐up reader interpretations of a text.     

Relationship between abdominal adiposity,cardiovascular fitness,and biomarkers of cardiovascular risk in British adolescents

BackgroundPuberty is a critical time in the development of overweight and obesity. The aim of this study was to examine relationships between measures of adiposity, cardiovascular fitness, and biomarkers of cardiovascular disease risk in adolescents.MethodsIn a cross-sectional study design, 129 girls and 95 boys aged 12.9–14.4 years at various stages of puberty were included, along with their mothers (n = 217) and fathers (n = 207). Anthropometric assessments of adiposity were made, along with cardiovascular physical fitness, using the 20-m shuttle run test, and biomarkers associated with cardiovascular risk, including glucose, insulin, triglyceride, fibrinogen, and C-reactive protein (CRP) concentrations.ResultsWaist-to-height ratio values were similar in boys and girls and correlated positively with diastolic blood pressure, insulin, triglyceride, fibrinogen, and CRP concentrations, and inversely with cardiovascular fitness scores. Skinfold thickness measurements were higher in girls. High-molecular-weight adiponectin concentrations were lower in boys than girls, particularly in late puberty, and CRP levels were higher. Cardiovascular fitness, maternal body mass index (BMI), and paternal BMI contributed independently to the variance in waist measurements in girls and boys. Gender, triceps skinfold thickness, and weight-to-height ratio, but not parental BMI, contributed independently to the variance in cardiovascular fitness.ConclusionThere is a relationship between measures of adolescent adiposity and parental weight that involves factors other than cardiovascular fitness. Adolescent boys have relatively more abdominal fat than girls and a tendency to have a proinflammatory profile of biomarkers. These observations suggest that family and social environmental interventions are best undertaken earlier in childhood, particularly among boys.     

Revealed word-of-mouth demand and adaptive supply: survival of motion pictures at the Australian box office

This study considers a frailty duration approach to modelling the life-length of a sample of 360 films that went into wide release at the Australian box office from 1 January 2000 to 31 December 2005. The analysis extends previous research by considering a range of film-specific covariates relating to distribution, production, consumer signals, and weekly performance. In particular, it is shown that film success (defined in a duration context) responds to previewing, advertising, critical reviews, and US box office—but not to production budget, star power or opening-week screens. The study also reveals that it is appropriate to account for unobservable heterogeneity between films in the choice of empirical methodology.     

Student activity levels, lesson context, and teacher behavior during middle school physical education

There is little research on students' engagement in physical activity in middle school physical education (PE). We observed student activity, lesson context, and teacher behavior in 430 PE lessons taught by 126 teachers in 24 schools. Variables were analyzed by mixed-model nested analyses of covariance. Boys were more active than girls overall and during skill drills, game play, and free play. Student activity varied by lesson context, with fitness activities producing the most activity. Class size was negatively associated with student activity. Daily PE contributed a weekly total of 25 min of vigorous activity and 83 min of moderate-to-vigorous activity--much less than national objectives. Results suggest that numerous opportunities exist for increasing student physical activity during middle school PE.