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The sterile insect technique has been routinely used to eradicate fruit fly Bactrocera tryoni (Froggatt) incursions. This study considers whether fly quality in a mass-rearing facility can be improved by reducing irradiation doses, without sacrificing reproductive sterility. Pupae were exposed to one of five target irradiation dose ranges: 0, 40-45, 50-55, 60-65, and 70-75 Gy. Pupae were then assessed using routine quality control measures: flight ability, sex ratio, longevity under nutritional stress, emergence, and reproductive sterility. Irradiation did not have a significant effect on flight ability or sex ratio tests. Longevity under nutritional stress was significantly increased at 70-75 Gy, but no other doses differed from 0 Gy. Emergence was slightly reduced in the 50-55, 60-65, and 70-75 Gy treatments, but 40-45 Gy treatments did not differ from 0 Gy, though confounding temporal factors complicate interpretation. Reproductive sterility remained acceptable (> 99.5%) for all doses--40-45 Gy (99.78%), 50-55 Gy (100%), 60-65 Gy (100%), and 70-75 Gy (99.99%). We recommend that B. tryoni used in sterile insect technique releases be irradiated at a target dose of 50-55 Gy, providing improved quality and undiminished sterility in comparison with the current 70-75 Gy standard while also providing a substantial buffer against risk of under dosing.

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For over 30 years, the International Atomic Energy Agency (IAEA) and the World Health Organization (WHO) have jointly monitored activities of secondary standard dosimetry laboratories (SSDLs) through postal dose audits with the aim of achieving consistency in dosimetry throughout the world. The Australian Nuclear Science and Technology Organisation (ANSTO) maintains an SSDL and is a member of the IAEA/WHO SSDL Network. Postal dose audit results at this Australian SSDL from 2001 to 2011 demonstrate the consistency of absorbed dose to water measurements, underpinned by the primary standard maintained at the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA).

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Nicorandil-induced ulceration is rare but has been reported at multiple sites throughout the gastrointestinal tract. We report a life-threatening complication of such ulceration - catastrophic per-rectal haemorrhage requiring emergency surgery with no prior symptoms. Whilst nicorandil should be considered in cases of chronic peri-anal and peristomal ulceration which fail to respond to conventional treatments, this case highlights its importance in the setting of acute surgical presentations.

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The reference air kerma rates of a set of individual (125)I seeds were calculated from current measurements of a calibrated re-entrant ionisation chamber. Single seeds were distributed to seven Australian brachytherapy centres for the same measurement with the user's instrumentation. Results are expressed as the ratio of the reference air kerma rate measured by the Australian Nuclear Science & Technology Organisation (ANSTO) to the reference air kerma rate measured at the centre. The intercomparison ratios of all participants were within +/-5% of unity.

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Primary standardisation was performed on a solution of (18)F using the 4pibeta-gamma coincidence counting efficiency-tracing extrapolation method with (60)Co used as a tracer nuclide. The result was used to calibrate the ANSTO secondary standard ionisation chamber which is used to disseminate Australian activity standards for gamma emitters. Using the secondary activity standard for (18)F, the Capintec CRC-712M dose calibrator at the Australian National Medical Cyclotron (NMC) Positron Emission Tomography (PET) Quality Control (QC) Section was calibrated. The dial setting number recommended by the manufacturer for the measurement of the activity of (18)F is 439. In this work, the dial setting numbers for the activity measurement of the solution of (18)F in Wheaton vials were experimentally determined to be 443+/-12, 446+/-12, 459+/-11, 473+/-15 for 0.1, 1, 4.5 and 9ml solution volumes, respectively. The uncertainties given above are expanded uncertainties (k=2) giving an estimated level of confidence of 95%. The activities determined using the manufacturer recommended setting number 439 are 0.8%, 1.4%, 4.0% and 6.5% higher than the standardised activities, respectively. It is recommended that a single dial setting number of 459 determined for 4.5ml is used for 0.1-9ml solution in Wheaton vials in order to simplify the operation procedure. With this setting the expended uncertainty (k=2) in the activity readout from the Capintec dose calibrator would be less than 6.2%.

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Calibration of a High-Dose-Rate 1000 Plus ionisation chamber and associated electrometer for the determination of reference air kerma rate for 125I brachytherapy seeds has been developed. Traceability was established from ionisation chamber measurements of an Amersham model 6711 125I seed for which a primary standard measurement of reference air kerma rate has been made by the National Institute of Standards and Technology. The status of an Australian secondary standard is to be realised by establishing legal verifying authority from the National Measurement Institute. The calibrated chamber thus provides a measurement from which similar chambers in hospitals may be calibrated. For quality assurance this result was compared with the calibration certificate supplied by the Accredited Dosimetry Calibration Laboratory of the University of Wisconsin, USA.

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Numerous applications in mechanical CAD/CAM need robust algorithms for the identification of protrusion and depression features (DP-features) on geometric models with free-form (B-Spline) surfaces. This paper reports a partitioning algorithm that first identifies the boundary edges of DP-features and then creates a surface patch to cover the depressions or isolate the protrusions. The novelty of the method lies in the use of tangent continuity between edge segments to identify DP-feature boundaries that cross multiple faces and geometries.

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A revision is made of the previously poorly studied blackfly fauna from the south-western border of Guyana with Brazil. Notes on the biosystematics of the species found are provided, together with keys and illustrations based on their morphology. Of the 14 species recorded, eight are anthropophilic and two of these (Simulium oyapockense s.l. and S. guianense s.l.) are proven vectors of human onchocerciasis in the nearby Amazonia focus of the disease in neighbouring Brazil.

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A revision is made of the previously poorly studied blackfly fauna from the south-western border of Guyana with Brazil. Notes on the biosystematics of the species found are provided, together with keys and illustrations based on their morphology. Of the 14 species recorded, eight are anthropophilic and two of these (Simulium oyapockense s.l. and S. guianense s.l.) are proven vectors of human onchocerciasis in the nearby Amazonia focus of the disease in neighbouring Brazil.

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AIMS: To examine the extent to which problem alcohol users' self reports of drinking pattern and symptomatology derive primarily from a functional, learned social-cognitive schema (referred to as a 'script' in this paper), rather than from acts of recall or memory. METHODS: Using a between-groups design with one repeated (within-subjects) measure, problem drinkers and non-problem drinkers were asked to complete a questionnaire about drinking behaviour and symptoms. Each group filled in the questionnaire twice, under both of two conditions. In condition one, they used the questionnaire to describe their own drinking and in condition two they were asked to describe the drinking of the other group (i.e. the problem drinkers filled out the questionnaire to describe non-problem drinking and the non-problem drinkers described problem drinking). RESULTS: Using analyses of variance for the different sub-scales of the questionnaire, no overall differences were found between the two groups on four of the five subscales. However, clear and significant differences were found between the two conditions. That is, both groups were able to produce clearly differentiated scripts for both problem drinking and non-problem drinking. CONCLUSIONS: These data, together with related data from other sources, suggest that 'scripts' for problem drinking and for non-problem drinking can be elicited from both problem-drinking and non-problem-drinking groups. The data support conclusions from an earlier study, suggesting that subjects may use learned 'scripts' rather than recall when responding to certain types of questionnaire instruments.

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Cytotaxonomic analysis of the polytene chromosomes from larvae of the Simulium damnosum Theobald complex from the island of Bioko in Equatorial Guinea is reported, and a new endemic cytoform is described. Chromosomally this cytoform is close to both S. squamosum (Enderlein) and S. yahense Vajime & Dunbar, but is not identical to either. However, it is morphologically and enzymatically identical to S. yahense. The Bioko form was also found to differ from other cytoforms of the S. damnosum complex in West Africa in the copy number or RFLP pattern of several different repetitive DNA sequences. It is clear that the Bioko form is genetically distinct from other populations of the S. damnosum complex, and whilst it is closest to S. yahense, it shows features that suggest a high degree of geographical and genetic isolation. Such isolation is an important consideration in the assessment of the potential for onchocerciasis vector eradication on Bioko.

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There have been numerous case studies and press reports of individuals committing acts of extreme violence while taking large doses of Anabolic-Androgenic Steroids (AAS). However, research using psychometric measures of aggression has tended to use small numbers of subjects which makes generalizing results difficult. In the current study the State Trait Anger Expression Inventory (STAXI) was administered to 50 AAS users and 40 non AAS-using control subjects. Subjects also underwent a semistructured interview focusing on AAS's effects on levels of aggression. Results showed that AAS users reported being significantly less in control of their aggression than controls. The semi-structured interview findings showed that elevations in aggression due to AAS use were reported by 60 per cent of AAS users. However, these elevations appeared more related to irritability and bad temper than acts of physical violence. The study also found that more AAS users than controls had worked as doormen/bouncers. This highlights the issue of whether AAS use causes aggression or whether aggressive individuals are attracted to AAS use. Future research should investigate this question.

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Phosphoglucomutase (PGM) and trehalase (Tre) isoenzymes of five species of Simulium blackflies (Diptera: Simuliidae), vectors of onchocerciasis in Venezuela, were investigated by means of a portable electrophoresis field kit. Tre differed between S. incrustatum and S. oyapockense s.l. Electrophoretic variation of Tre in other members of the S. amazonicum and S. incrustatum groups merit further investigation. PGM appears to be more useful for separating populations within species complexes. Multiple populations and/or seasonal changes in population structure of S. guianense s.l., S. exiguum s.l. and S. metallicum s.l. were inferred from elecrophoretic variation of PGM.

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This study examined HIV and hepatitis risk behaviours among anabolic-androgenic steroid (AAS) users and controls, providing a detailed assessment of both injection and sexual practices. Fifty AAS-using and 40 non-AAS-using weight trainers completed a semi-structured interview followed by a detailed questionnaire. The 'high risk' behaviour of sharing needles and syringes was not current practice among the AAS-using sample, with only one user reporting sharing injecting equipment in the past. However, for some users it was common practice to share multi-dose vials (19%) and to divide drugs using syringes (17%). Both these practices are potential routes for HIV and hepatitis infection. Significantly more AAS users (36%) reported increases in sex drive over the last three months than did the control subjects (5%). More AAS users than controls were engaging in sex with more than one partner while infrequently using condoms. These findings support the maintenance of needle exchange schemes which are essential to continued safe injecting practices among AAS users. The elevated sexual risk behaviour of AAS users could be due to AAS's effect of increasing sex drive or to a 'risk taking' personality trait among AAS users.

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The presence of Onchocerca volvulus DNA in experimentally infected flies can now be detected by use of the PCR, so that, for example, one infected Simulium damnosum can be detected in a pool of 100 uninfected flies or one S. ochraceum can be detected in pools of 20-40. As this PCR technique is specific for O. volvulus, the results are not confounded by the presence of other, unimportant, Onchocerca species, and the technique could replace time-consuming, manual dissection of flies. In 1996 and 1997, pools of 16-21 Simulium ochraceum were tested by the PCR technique. These flies had been collected biting man, between 1992 and 1994, from two hyperendemic coffee estates (fincas) in Guatemala, and stored in commercial (95%) ethanol. Collections at finca Buena Vista (869 flies in 52 pools) were made 1-2 weeks and 46 weeks after 45% of eligible subjects had been treated with ivermectin for the first time. At finca El Brote, collections (360 flies in 18 pools) were made 13 weeks before and 7 weeks after 97% of eligible subjects had received their first treatment. DNA was easily recovered from simuliids that had been stored in ethanol for up to 4 years. Of the nine pools of flies with visible blood collected at Buena Vista, each of 20 flies, eight tested positive for O. volvulus DNA. In flies without blood, 13 of 22 pools collected at Buena Vista just after treatment tested positive, whereas there were 14 positives in 22 pools taken 46 weeks later (P > 0.05). At El Brote, nine of 10 pre-treatment pools were positive, compared with three of eight taken 7 weeks post-treatment (P = 0.04), indicating that the treatments in this finca had reduced infection in the vector, and possibly transmission, by about 60%. A sub-sample of Buena Vista flies was divided into 19 sets of three separate sub-pools containing heads, thoraces and abdomens. Three pools of heads alone were positive, and had corresponding pools of positive abdomens. Three positive pools of thoraces had negative corresponding pools of heads and abdomens. These results show that PCR can be used to determine the prevalence of O. volvulus DNA in wild-caught S. ochraceum. As the infection rates observed were higher than expected from dissections reported by other workers, PCR-determined rates may not be directly comparable with traditional parameters based on the dissection of flies to reveal O. volvulus larvae.

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A fit young man sustained a ruptured diaphragm during a recreational scuba dive three months after undergoing an uncomplicated laparoscopic Nissen fundoplication for gastro-oesophageal reflux disease. It is proposed that this rare occurrence was attributable to gastrointestinal barotrauma. The injury was treated by laparotomy, mobilisation of herniated abdominal viscera back into the abdomen, repair of the crura and gastropexy. He made a full postoperative recovery. It is concluded that scuba diving should be avoided in patients who have undergone fundoplication.

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Pharmacological/physiological models and social process/cognitive models of addiction are compared. These are discussed both in terms of the types of data produced and the philosophies of knowledge that underlie the two approaches. It is suggested that the notion of addiction confounds these two sets of issues, especially with respect to the notions of volition and compulsion. The problem is highlighted by data that reveal verbal reports to be variable and context dependent. It is concluded that a better understanding of the nature of addiction requires a clearer distinction between the pharmacological/physiological approach and the social process/cognitive approach. Both approaches contribute usefully to knowledge and have predictive value. Confusion arises, however, where workers fail to see not merely the benefits, but also the limitations, of these two approaches to the addiction problem.

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