Antigen-specific interferon-gamma release is decreased following the single intradermal comparative cervical skin test in African buffaloes (Syncerus caffer).

Effective disease management of wildlife relies on the strategic application of ante-mortem diagnostic tests for early identification and removal of M. bovis-infected animals. To improve diagnostic performance, interferon-gamma release assays (IGRAs) are often used in conjunction with the tuberculin skin test (TST). Since buffaloes are major maintenance hosts of M. bovis, optimal application of bovine TB diagnostic tests are especially important. We aimed to determine whether the timing of blood collection relative to the TST has an influence on IFN-γ production and diagnostic outcome in African buffaloes. Release of IFN-γ in response to bovine purified protein derivative (PPD), avian PPD and PC-HP® and PC-EC® peptides was measured by Bovigam® and an in-house IGRA in a group of Bovigam®-positive and - negative buffaloes at the time the TST was performed and three days later. There was significantly lower IFN-γ release in response to these antigens post-TST in Bovigam®-positive buffaloes, but no significant changes in Bovigam®-negative buffaloes. Also, a significantly greater proportion of buffaloes were Bovigam®-positive prior to the TST than three days later. We therefore recommend that blood samples for use in IGRAs be collected prior to or at the time the TST is performed to facilitate the correct identification of greater numbers of IGRA-positive buffaloes.

Working the night shift: a necessary time for training or a risk to health and safety?

The European Working Time Directive (EWTD) limits excessive night shifts and restricts the working week to no more than 48 hours. The underlying rationale is to minimise the health risks to all workers. Here we debate the impact of night rotas for doctors-in-training on patient safety and medical education; when the EWTD was agreed these topics may not have been considered, either systematically or objectively. The impacts of diurnal rhythms on human functions affect all night workers, but the nature of rostered medical and surgical work has little precedent in other industries or even in the contracts of other healthcare staff. For example, rostered night duties need to be distinguished from permanent night shift work. On-call medical night work from training doctors is generally required for short periods and usually involves fewer patients. It is an important time in training, where clinical responsibility and decision-making can be matured in a supervised setting. To comply with the EWTD most hospitals have adopted rota patterns that aim to cover the clinical needs, while ensuring no doctor works for more than 48 hours in an average working week. To monitor this process longterm studies are necessary to evaluate effects on a doctor's health and on patient care generally. The EWTD has also led to a loss of continuity of patient care; does this really matter?

Introduction, establishment, and potential geographic range of Carmenta sp. nr ithacae (Lepidoptera: Sesiidae), a biological control agent for Parthenium hysterophorus (Asteraceae) in Australia.

Parthenium (Parthenium hysterophorus L.), a major weed causing economic, environmental, and human and animal health problems in Australia and several countries in Asia, Africa, and the Pacific, has been a target for biological control in Australia since the mid-1970s. Nine species of insects and two rust fungi have been introduced as biological control agents into Australia. These include Carmenta sp. nr ithacae, a root feeding agent from Mexico. The larvae of C. sp. nr ithacae bore through the stem-base into the root where they feed on the cortical tissue of the taproot. During 1998-2002, 2,816 larval-infested plants and 387 adults were released at 31 sites across Queensland, Australia. Evidence of field establishment was first observed in two of the release sites in central Queensland in 2004. Annual surveys at these sites and nonrelease sites during 2006-2011 showed wide variations in the incidence and abundance of C. sp. nr ithacae between years and sites. Surveys at three of the nine release sites in northern Queensland and 16 of the 22 release sites in central Queensland confirmed the field establishment of C. sp. nr ithacae in four release sites and four nonrelease sites, all in central Queensland. No field establishment was evident in the inland region or in northern Queensland. A CLIMEX model based on the native range distribution of C. sp. nr ithacae predicts that areas east of the dividing range along the coast are more suitable for field establishment than inland areas. Future efforts to redistribute this agent should be restricted to areas identified as climatically favorable by the CLIMEX model.

Biological control of weeds.

Classical biological control, i.e. the introduction and release of exotic insects, mites, or pathogens to give permanent control, is the predominant method in weed biocontrol. Inundative releases of predators and integrated pest management are less widely used. The United States, Australia, South Africa, Canada, and New Zealand use biocontrol the most. Weeds in natural ecosystems are increasingly becoming targets for biocontrol. Discussion continues on agent selection, but host-specificity testing is well developed and reliable. Post-release evaluation of impact is increasing, both on the target weed and on non-target plants. Control of aquatic weeds has been a notable success. Alien plant problems are increasing worldwide, and biocontrol offers the only safe, economic, and environmentally sustainable solution.

Gender, status and 'powerless' speech: interactions of students and lecturers.

The present study investigated whether the use of 'powerless' speech was affected by role status, speaker's gender and gender of another participant. Fifty-two university lecturers and 156 students participated. Students were paired with a lecturer or student of the same or opposite sex. The findings placed a question mark over the link between powerless speech and individuals of low role status. Moreover, against hypothesis, speaker's gender and gender of partner did not affect the use of qualifiers or fillers, although they affected the use of tag questions and some types of hesitation. A qualitative analysis was also conducted which suggested that the powerless features were, in fact, multi-functional with respect to power. In addition, the importance of a variety of interactional techniques, such as credibility techniques, in the creation or negotiation of relational power was documented. As a whole, these findings highlight problems with the concept of 'powerless' speech, at least with respect to relational power.

Language comprehension and expression among adolescents who have experienced childhood physical abuse.

The present study compared the expressive and receptive language abilities of adolescents who had experienced physical abuse as children with the abilities of a closely matched control group who had not experienced maltreatment. Comprehension abilities of the two groups (as measured on a standard test) did not differ significantly. There were also no significant differences in expressive vocabulary. The syntactic expression of the abused group was significantly more impaired than that of the non-abused group. In addition, two aspects of functional communication were impaired significantly. The abused used significantly less self-related language and also had a significantly greater tendency to engage in self-repetition. The two groups did not differ significantly, however, on several other aspects of functional communication. Explanations of the results are offered. It is also suggested that there are individual differences in the types of problem experienced by the physically abused group.

Manners of expressing negative and sympathetic attitudes towards the unemployed.

Social psychologists have examined ways in which indirectness and discursive techniques allow the communication of prejudice while not breaching the tolerance norm. The role these techniques play in the expression of other kinds of attitude, however, is as yet unknown. The present study examined the discursive techniques used by 67 employed individuals to express negative and sympathetic attitudes towards the unemployed. A style of directness was used significantly more frequently to express sympathetic attitudes than negative attitudes. Conversely, credibility techniques were used significantly more frequently to express negative attitudes than sympathetic attitudes. These credibility techniques were used in conjunction with either directness or indirectness. However, against hypothesis, indirectness alone was not used more frequently to express negative than sympathetic attitudes; in fact, one type of indirectness was associated to a greater extent with the expression of sympathy than with negativity. It was predicted that professionally employed individuals would tend to use different discursive techniques than non-professionally employed individuals. This prediction, while supported by a difference on a composite measure of the manners of expression, was not confirmed for any of the styles considered separately.

Parthenium weed and human health in Queensland.

Allergic reactions to the pollen and plant dust of parthenium weed are causing major health problems in central Queensland, which can be expected to increase, especially as the pasture weed is rapidly spreading south. This paper reviews published information on health aspects of this weed and calls attention to its spread into areas with much greater population.