A comparison of the performance and biological efficiency of new knapsack sprayers and a controlled droplet application (CDA) sprayer for the control of the diamondback moth, Plutella xylostella L. (Lepidoptera : Plutellidae)

Field trials and laboratory bioassays were undertaken to compare the performance and efficacy (mortality of diamondback moth larvae) of insecticides applied to cabbages with three high volume hydraulic knapsack sprayers (NS-16, PB-20 and Selecta 12V) and a controlled droplet application (CDA) sprayer. In field experiments, the high volume knapsack sprayers (application rate 500-600 L ha(-1)) provided better spray coverage on the upper and lower surfaces of inner leaves, the upper surfaces of middle and outer leaves, and greater biological efficacy than the CDA sprayer (application rate 20similar to40 L ha(-1)). The PB-20 provided better spray coverage on the upper surface of middle leaves and both surfaces of outer leaves when compared with the Selecta 12V. However, its biological efficacy in the field was not significantly different from that of the other high volume sprayers. Increasing the application rate from 20 to 40 L ha(-1) for the CDA sprayer significantly increased droplet density but had no impact on test insect mortality. Laboratory evaluations of biological efficacy yielded higher estimates than field evaluations and there was no significant difference between the performance of the PB-20 and the CDA sprayer. Significant positive relationships were detected between insect mortality and droplet density deposited for both the PB-20 and the CDA sprayers.

Esmodil: An acetylcholine mimetic resurfaces in a southern australian marine sponge Raspailia (Raspailia) sp.

Bioassay directed fractionation of a Raspailia (Raspailia) sp. (Order Poecilosclerida; Family Raspailiidae) collected during scientific trawling operations off the Northern Rottnest Shelf yielded as nematocidal agents the known metabolites, phorboxazoles A (1) and B (2). Further examination revealed the new natural product but known synthetic compound, esmodil (3). The structure for 3 was confirmed by spectroscopic analysis and total synthesis.

Startle-potentiation during nonaversive human conditioning

Fear-potentiated startle is a well-established measure of emotional learning in nonhuman animals. In humans, startle potentiation in anticipation of an aversive unconditional stimulus (US) has been interpreted as reflecting the same emotional process. This interpretation was supported by previous failures to fmd startle potentiation in anticipation of nonaversive USs, reactiontime tasks. The present research questions these results. Experiment 1 found startle-potentiation in anticipation of an aversive US, which resulted in increased dislike of the conditional stimulus (CS), and in anticipation of a nonaversive US, which did not affect CS valence. Experiment 2 replicated the latter finding, indicating that provision of performance feedback enhanced the salience of the reaction time task USs and thus anticipatory startle potentiation. The present results pose problems for the interpretation of fmdings of potentiated startle in human-aversive conditioning as reflecting emotion. Rather, startle potentiation during aversive and non-aversive conditioning may reflect the attentional processes known to occur during human-associative learning.

'We're not going to take it!' - Academics on the rampage

What are the social factors that can change apathy to action? Two survey-based field studies were conducted with National Tertiary Education Union members, to investigate the interplay between individual and group-based psychological processes in union support. The first study was conducted in an industrially calm context and the second, following a national strike in the Australian university sector. Drawing on social identity theory, the studies investigated both individual and group-related factors including: (a) instrumental and ideological attitudes; (b) employee identity; (c) perceptions of employment-related threat, and of relations with management; and (d) normative support for the union amongst fellow employees. Consistent with predictions, groupbased factors (i.e., perceived context and normative support) moderated the role of instrumental and ideological beliefs in the behavioural expression of union support. A subset of participants, who responded at both times, provided additional evidence for the importance of contextually activated group-processes to changes in union behaviour.

What is an effective health consumer? A convergent interviewing approach

This study is part of a larger project on the measurement of effective health consumers in the context of musculoskeletal illness. This complex issue involves the progressive nature of the disease, invisibility of the illness and attendant impairments, complexity of decision-making and negotiation, and urgent need to translate emergent evidence about treatment and management to patients and health professionals. We conducted indepth interviews with patients, family members, general practitioners, specialist clinicians, and health consumer advocates (N = 84) about effective consumers in this context, using a process of convergent interviewing, with convergence conducted within and across groups and countries. The initial set of themes included information seeking and adaptation, decision-making, roles of patients, GPs, and specialists and communication between them, importance of pain and impact of depression, impact of the social environment (including the invisibility of the disease and the need for a normal life), and coping strategies.

Monocular transparency is not a new form of unpaired stereopsis

Howard and Duke (2003) generated stereograms with a grey transparent square offset from a vertical bar in one eye, and a vertical bar with a gap in the other eye. They argued that these displays were 'without conventional disparity' and that the metrical depth experienced was a new form of unpaired stereopsis due to 'transparency rather than occlusion'. Another possibility is that the perceived depth in these displays was obtained from horizontal contours. To test this possibility, we generated three displays that contained similar horizontal contourterminations, but were inconsistent with transparency. Reliable depth was seen in all stimuli. We conclude that in our stimuli, and those of Howard and Duke, transparency is not responsible for the perception of depth, which appears to be based instead on disparate horizontal contour terminations. Our results also show that disparate contours of opposite contrast polarity can generate depth.