Medial prefrontal cortex control of the Paraventricular hypothalamic nucleus response to psychological stress: Possible role of the bed nucleus of the stria terminalis

The medial prefrontal cortex (mPFC) has been strongly implicated in control of the paraventricular nucleus of the hypothalamus (PVN) response to stress. Because of the paucity of direct projections from the mPFC to the PVN, we sought to investigate possible brain regions that might act as a relay between the two during psychological stress. Bilateral ibotenic acid lesions of the rat mPFC enhanced the number of Fos-immunoreactive cells seen in the PVN after exposure to the psychological stressor, air puff. Altered neuronal recruitment was seen in only one of the candidate relay populations examined, the ventral bed nucleus of the stria terminalis (vBNST). Furthermore, bilateral ibotenic acid lesions of the BNST caused a significant attenuation of the PVN response to air puff. To better characterize the structural relationships between the mPFC and PVN, retrograde tracing studies were conducted examining Fos expression in cells retrogradely labeled with cholera toxin b subunit (CTb) from the PVN and the BNST. Results obtained were consistent with an important role for both the mPFC and BNST in the mpPVN CRF cell response to air puff. We suggest a set of connections whereby a direct PVN projection from the ipsilateral vBNST is involved in the mpPVN response to air puff and this may, in turn, be modulated by an indirect projection from the mPFC to the BNST. (C) 2004 Wiley-Liss, Inc.

Self-determination theory: A case study of evidence-based coaching

The coach is central to the development of expertise in sport (Bloom, 1985) and is subsequently key to facilitating adaptive forms of motivation to enhance the quality of sport performance (Mallett & Hanrahan, 2004). In designing optimal training environments that are sensitive to the underlying motives of athletes, the coach requires an in-depth understanding of motivation. This paper reports on the application of self-determination theory (SDT; Deci & Ryan, 1985; Ryan & Deci, 2000) to coaching elite athletes. Specifically, the application of SDT to designing an autonomy-supportive motivational climate is outlined, which was used in preparing Australia's two men's relay teams for the 2004 Olympic Games in Athens.

Comparative ultrasonographic investigations of the gastrointestinal tract and the liver in healthy and diseased pigeons

The use of ultrasound as a diagnostic tool in birds has been documented for cardiac, urogenital, and liver disease. However, its use in gastrointestinal tract disease is not defined. Therefore, the purpose of this study was to compare the ultrasonographic findings of the intestine and liver of six healthy racing pigeons with those of six racing pigeons with gastrointestinal disease. The echogenicity of the liver was significantly different between the two groups. Pigeons with gastrointestinal disease had less homogeneous liver echogenicity with focal heterogeneous areas and the hepatic blood vessels were visible and dilated. The duodenum was visualized and its mean diameter of 7.2 +/- 0.3 mm in the diseased pigeons was significantly wider (P < 0.001) than the 5.7 +/- 0.2 mm in healthy birds. The thickness of the duodenal wall in healthy and diseased pigeons was 1.6 +/- 0.1 and 2.4 +/- 0.1 mm, respectively, and they were significantly different (P < 0.001). We defined baseline measurements for the duodenal loop in pigeons and provided evidence that ultrasound can be a useful diagnostic tool for investigating intestinal disease in pigeons.

Impact of two different body mass management strategies on repeat rowing performance

Purpose: The present study was conducted to examine the impact of acute weight loss on repeat 2000-m rowing ergometer performance during a simulated multiday regatta. and to compare two different body mass management strategies between races. Methods: Competitive rowers (N = 16) were assigned to either a control (CON), partial recovery (RECpartial), or complete recovery (RECcomplete) group. Volunteers completed four trials, each separated by 48 h. No weight restrictions were imposed for the first trial. Thereafter, athletes in RECpartial and RECcomplete were required to reduce their body mass by 4% in the 24 h before trial 2, again reaching this body mass before the final two trials. No weight restrictions were imposed on CON. Aggressive nutritional recovery strategies were used in the 2 h following weigh-in for all athletes. These strategies were maintained for the 12-16 h following racing for RECcomplete with the aim of restoring at least three quarters of the original 4% body mass loss. Postrace recovery strategies were less aggressive in RECpartial; volunteers were encouraged to restore no more than half of their initial 4% body mass loss. Results: Acute weight loss increased time to complete the first at-weight performance trial by a small margin (mean 3.0, 95% CI -0.3 to 6.3 s, P = 0.07) when compared with the CON response. This effect decreased when sustained for several day,. Aggressive postrace recovery strategies tended to eliminate the effect of acute Weight loss on subsequent performance. Conclusion: Acute weight loss resulted in a small performance compromise that was reduced or eliminated when repeated over several days. Athletes should be encouraged to maximize recovery in the 12-16 h following racing when attempting to optimize subsequent performance.

'Look at that kid crawling': Race, myth and the 'crawl' stroke

Australia and, more specifically, a Solomon Island schoolboy named A lick Wickham, are credited with creating the swimming racing stroke, the crawl, or freestyle as it is known in contemporary parlance. Wickham's contribution constitutes a popular celebrated and enduring legend. While there is some factual basis to the legend, Wickham s contribution is a sport creation myth. The myth offers an example of the intersection of sport and constructions of Pacific islanders in the racial discourse of the Federation period. As a cultural discourse, the myth reflects how Wickham was accommodated as an exoticised islander and socially acceptable 'black' sportsman.

Acute weight loss followed by an aggressive nutritional recovery strategy has little impact on on-water rowing performance

Objectives: To assess the influence of moderate, acute weight loss on on-water rowing performance when aggressive nutritional recovery strategies were used in the two hours between weigh in and racing. Methods: Competitive rowers (n=17) undertook three on-water 1800 m time trials under cool conditions ( mean (SD) temperature 8.4 (2.0)degrees C), each separated by 48 hours. No weight limit was imposed for the first time trial-that is, unrestricted body mass (UNR1). However, one of the remaining two trials followed a 4% loss in body mass in the previous 24 hours (WT-4%). No weight limit was imposed for the other trial (UNR2). Aggressive nutritional recovery strategies (WT-4%, 2.3 g/kg carbohydrate, 34 mg/kg Na+, and 28.4 ml/kg fluid; UNR, ad libitum) were used in the first 90 minutes of the two hours between weigh in and performance trials. Results: WT-4% had only a small and statistically non-significant effect on the on-water time trial performance ( mean 1.0 second, 95% confidence interval (CI) 20.9 to 2.8; p=0.29) compared with UNR. This was despite a significant decrease in plasma volume at the time of weigh in for WT-4% compared with UNR (-9.2%, 95% CI -12.8% to -5.6%; p

Man and boy with Queensland Peace Committee banner during Aldermaston Peace march in 1964

Man and boy with Queensland Peace Committee banner during Aldermaston Peace march, Sunday, April 5th 1964. The Aldermaston march covered the distance between Ipswich and Brisbane, Australia, walked in relays covering approximately two miles each. Most relay sections were sponsored by one or more individual organisations.

Two men with placards during Aldermaston Peace march in 1964

Two men with placards during Aldermaston Peace march, Sunday, April 5th 1964. The Aldermaston march covered the distance between Ipswich and Brisbane, Australia, walked in relays covering approximately two miles each. Most relay sections were sponsored by one or more individual organisations.

Two men from the Bulimba Peace Group with placards during Aldermaston Peace march in 1964

Two men from the Bulimba Peace Group with placards during Aldermaston Peace march, Sunday, April 5th 1964. The Aldermaston march covered the distance between Ipswich and Brisbane, Australia, walked in relays covering approximately two miles each. Most relay sections were sponsored by one or more individual organisations.

Women from the Union of Australian Women with banner during Aldermaston Peace march in 1964

Women from the Union of Australian Women with banner during Aldermaston Peace march, Sunday, April 5th 1964. The Aldermaston march covered the distance between Ipswich and Brisbane, Australia, walked in relays covering approximately two miles each. Most relay sections were sponsored by one or more individual organisations. The Union of Australian Women is a national organisation that was formed in 1950. Its aim is to work for the status and wellbeing of women across the world. It has been involved in a wide variety of campaigns that concern women. The Union of Australian Women networks with other women's community and union groups on such issues.

Participants with peace banners during Aldermaston Peace march in 1964

Participants with peace banners during Aldermaston Peace march, Sunday, April 5th 1964. The Aldermaston march covered the distance between Ipswich and Brisbane, Australia, walked in relays covering approximately two miles each. Most relay sections were sponsored by one or more individual organisations.