Shoal familiarity modulates effects of individual metabolism on vulnerability to capture by trawling.

Impacts of fisheries-induced evolution may extend beyond life history traits to more cryptic aspects of biology, such as behaviour and physiology. Understanding roles of physiological traits in determining individual susceptibility to capture in fishing gears and how these mechanisms change across contexts is essential to evaluate the capacity of commercial fisheries to elicit phenotypic change in exploited populations. Previous work has shown that metabolic traits related to anaerobic swimming may determine individual susceptibility to capture in trawls, with fish exhibiting higher anaerobic performance more likely to evade capture. However, high densities of fish aggregated ahead of a trawl net may exacerbate the role of social interactions in determining an individual fish's behaviour and likelihood of capture, yet the role of social environment in modulating relationships between individual physiological traits and vulnerability to capture in trawls remains unknown. By replicating the final moments of capture in a trawl using shoals of wild minnow (Phoxinus phoxinus), we investigated the role of individual metabolic traits in determining susceptibility to capture among shoals of both familiar and unfamiliar conspecifics. We expected that increased shoal cohesion and conformity of behaviour in shoals of familiar fish would lessen the role of individual metabolic traits in determining susceptibility to capture. However, the opposite pattern was observed, with individual fish exhibiting high anaerobic capacity less vulnerable to capture in the trawl net, but only when tested alongside familiar conspecifics. This pattern is likely due to stronger cohesion within familiar shoals, where maintaining a minimal distance from conspecifics, and thus staying ahead of the net, becomes limited by individual anaerobic swim performance. In contrast, lower shoal cohesion and synchronicity of behaviours within unfamiliar shoals may exacerbate the role of stochastic processes in determining susceptibility to capture, disrupting relationships between individual metabolic traits and vulnerability to capture.

Advanced rural skills training: are recently qualified GPs using their procedural skills?

INTRODUCTION: The number of GPs providing procedural services in rural areas is declining; however, few studies have investigated issues directly relevant to recently qualified doctors. Limited published data and anecdotal reports in Australia suggest that a large proportion of doctors leave rural procedural practice soon after training. This study aimed to: (1) describe where GPs practice in the 5 years after advanced rural skills training; (2) describe the proportion of doctors using their advanced skills; (3) measure doctors' ratings of the quality of support and how critical the year directly following training is in future career choices; and (4) measure the association between support and use of advanced skills. METHODS: A cross-sectional, postal survey was undertaken of doctors who had completed advanced rural skills training in Queensland between 1995 and June 2009. Data were collected on a three-page, structured questionnaire. General practice colleges, the three Queensland regional training providers and one national training provider were approached in order to identify and mail questionnaires to eligible doctors. Descriptive statistics were prepared for practice history information, and attitudinal ratings. A χ(2) test was used to analyse the association between support and use of skills. RESULTS: Sixty-one completed questionnaires were returned resulting in an unadjusted response rate of 51.7%. Respondents had completed a range of training posts: obstetrics and gynaecology (37.7%), anaesthetics (18%), anaesthetics and obstetrics and gynaecology (11.5%) and Aboriginal and Torres Strait Islander health (11.5%). Thirty-nine respondents (63.9%) were using skills related to their advanced training at the time of the study. In the first 5 years after training, the percentage of doctors using their advanced rural skills decreased from 75.4% to 61.1%. The year directly following advanced training was rated as 'critical' or 'very critical' in their future career choices by 68.9% of respondents. However, ratings of the quality of support received in that year were varied, with 21.4% reporting 'very poor' support. There was a statistically significant association between ratings of support in the year directly following training and the use of skills 3 years after training (χ(2) = 8.715, df = 2, p = 0.013). CONCLUSIONS: This study has shown that while the majority of doctors are using skills related to their advanced rural skills training, there is room for improvement through training and career planning support, extending formal support mechanisms into the first year after training, improving opportunities to use advanced skills and improving systems to re-engage doctors into procedural practice.

General practice research. Problems and solutions in participant recruitment and retention.

BACKGROUND: Increasing interest in general practice research, especially postal surveys, has been met with decreasing response rates. Prospective, longitudinal surveys pose additional concerns for general practice researchers, one of the major problems being sample attrition after project commencement. OBJECTIVE: This article draws on the authors' experiences from seven studies conducted by them to identify useful strategies for researchers who need to recruit general practitioners and/or their patients, with particular reference to retaining participants across time. A list of issues, lessons learned and possible strategies was developed which, although not exhaustive, probably reflects those commonly encountered in many general practice studies. DISCUSSION: The issues identified here are not necessarily new, but it is useful to revisit such issues and to review and reiterate methods and processes, as even experienced researchers encounter problems from time to time. Studies involving prolonged participation especially, require diligent consideration of likely recruitment/retention problems.

Interpractitioner communication: telephone consultations between rural general practitioners and specialists.

The results of a study that sought to investigate the utility of and satisfaction with telephone consultations from the perspective of general practitioners and specialists are reported. Semi-structured interviews with rural general practitioners and specialists were used to elicit information about their most recent telephone consultations. The telephone was found to be an important means of communication for rural practitioners, primarily in terms of organising referrals. General practitioners tended to called specialists who they knew and appeared to have fairly well-formed networks of specialists who they called for most of their concerns. Trust is an important element of interpractitioner communication as it increases understanding and confidence in the reliability of the information exchanged. Good working relationships ensure that rural general practitioners have an accessible source of acceptable specialist support.

Intravitreal sustained-release ganciclovir.

Current treatment of cytomegalovirus retinitis in patients with acquired immunodeficiency syndrome involves frequent intravenous administration of sodium ganciclovir that often results in unacceptable side effects. We have developed devices that release ganciclovir at rates of 2 micrograms/h and 5 micrograms/h in vitro. When implanted into the vitreous of rabbit eyes, mean intravitreal ganciclovir levels of 9 mg/L and 16 mg/L were maintained for more than 80 and 42 days, respectively. Devices were well tolerated, with no toxic effects attributable to the polymers used in the devices. This investigation indicates that these devices can maintain therapeutic levels of drug for extended periods and are well tolerated in the rabbit eye. They may prove useful in the clinical management of cytomegalovirus retinitis in patients with acquired immunodeficiency syndrome.

The use of viscoelastic substances in the drainage of postoperative suprachoroidal hemorrhage.

Suprachoroidal hemorrhage is a serious surgical complication occurring in up to 10% of aphakic patients undergoing filtration surgery. Surgical treatment includes drainage of the hemorrhage through sclerotomies and reformation of the anterior chamber with balanced salt solution or air. Two patients are presented whose suprachoroidal hemorrhages were managed with the instillation of 10% sodium hyaluronate. The intraocular administration of a space-occupying fluid produces an even distribution of hydraulic force to facilitate drainage of the hemorrhage and avoids the optical problems associated with the use of intraocular air. While most cases of suprachoroidal hemorrhage can be effectively managed using balanced salt solution or air, we believe that viscoelastic agents may be of special benefit in selected situations.

Whole-body retention, excretion and metabolism of [74As]arsenic acid in the hamster.

In order to assess the whole-body retention, excretion and metabolism of inorganic arsenic, male and female hamsters were given either a single oral or i.v. dose of 74As (congruent to 33' microCi/hamster; 0.01 micrograms arsenic/hamster) as arsenic acid. 74As radioactivity was measured in the whole body, urine and feces for up to 35 days. 24-h samples of urine were analyzed for arsenic metabolites. For the i.v. dosed hamsters, the half-period of elimination for the first component (65% of the dose) was 0.40 days; the second component (35% of the dose) had a half-period of 4.5 days. For the orally dosed hamsters, the half-period of elimination for the first component (98% of the dose) was 0.29 days; the second component (2% of the dose) had a half-period of 3.8 days. Differences in the percent of dose excreted between oral and i.v. dosed hamsters appeared to be due to the increased fecal excretion of arsenic (70%) in the orally dosed hamsters as compared to the i.v.v dosed hamsters (6%). No statistically significant differences between the i.v. and oral treatments were found in the half-periods of elimination for either of the 2 components. Analysis of the urine for metabolites revealed arsenic was present as dimethylarsinic acid and inorganic arsenic.

The composition of tea infusions examined in relation to the association between mortality and water hardness.

Recent epidemiological studies have shown that death-rates from certain chronic diseases are higher in areas with soft than in areas with hard drinking-water. In the striking negative correlation found in the county boroughs of England and Wales between cardiovascular mortality and water hardness the important underlying factor is apparently the water calcium. Interest is therefore focused on the dietary significance of calcium present in drinking-water. In relation to that interest, the present report gives a quantitative account of the composition of tea infusions prepared with waters containing different amounts of calcium. It is shown that a substantial part of water calcium is taken up by the tea leaf during the preparation of infusions. The analysis of the infusions covers a wide range of individual components, including trace metals and polyphenolic substances. It appears that the principal change caused in infusion composition by the presence of calcium in the water is a substantial reduction in the relatively high oxalate content. The question is raised whether there may be some connexion between the ;water factor' in cardiovascular disease and the absorption of oxalates from foods.