DDT and metabolites residues in the southern bent-wing bat (Miniopterus schreibersii bassanii) of south-eastern Australia

The southern bent-wing bat (Miniopterus schreibersii bassanii) is an insectivorous, obligate cave dwelling species found in south-eastern South Australia and western Victoria, Australia. In recent times, the finger of blame for an apparent population decline at Bat Cave, Naracoorte (one of only two known maternity roosts for this species, the other being Starlight Cave, Warrnambool) has been pointed at pesticide use in the region, following the finding of organochlorine and organophosphate insecticide residues in bat guano. This study sampled juvenile southern bent-wing bats from Bat Cave and Starlight Cave, and determined DDT, DDD and DDE concentrations in liver, pectoral muscle, brain and back-depot fat tissues.

Organochlorine and trace metal residues in adult southern bent-wing bat (Miniopterus schreibersii bassanii) in Southeastern Australia

In recent times, the apparent population decline of the southern bent-wing bat (Miniopterus schreibersii bassanii) at Bat Cave, Naracoorte has been ascribed to pesticide use in the region, following the finding of organochlorine and orgaonophosphate insecticide residues in bat guano. Adult southern bent-wing bats were collected from Bat Cave and Starlight Cave in 2003. Organochlorine contaminants were detected in all carcass samples: p,p′-DDE was by far the most dominant contaminant with concentrations ranging from 11 000 to 59 000 ng g⁻¹, followed by p,p′-DDT (110–1600 ng g⁻¹), p,p′-DDD (35–620 ng g⁻¹), ∑PCBs (33–490 ng g⁻¹), ∑chlordane and related compounds (7.9–270 ng g⁻¹), HCB (1.6–120 ng g⁻¹), HP epox. (3.1–230 ng g⁻¹), TCPMOH (3.8–38 ng g⁻¹), ∑HCHs (1.4–9.6 ng g⁻¹), and TCPMe (0.1–4.2 ng g⁻¹) (all values on lipid-weight basis). No significant difference in DDE, DDD, DDT, ∑DDT, ∑PCB, trans-chlordane, heptachlor epoxide, trans-nonachlor, α-HCH, β-HCH, γ-HCH, TCPMOH or TCPMe concentrations were observed either between sexes within sites, or between sites (p > 0.05). However, there were significant differences in HCB and oxychlordane concentrations between sexes and between sites (p < 0.05), between site differences in cis-nonachlor concentrations in male bats (p < 0.05), and cis-chlordane concentrations between sexes at Starlight Cave, and between males of each site (p < 0.05). There were also significant differences in the liver concentrations of some metals between sexes within sites (Ag, Cd, Co, Cu, Pb, Se, Zn), and between sites (Ag, Cd, Co, Cu, Hg, Pb, Se, V, Zn). Clustering or grouping of sites was observed when the OC data was expressed on a lipid-weight basis. These inter-site differences in OC concentrations reflect local exposure over a period of time, and do not unambiguously support any suggestion that we are witnessing incipient speciation. However, for conservation purposes, it may be prudent to assume that there are two sub-populations of M. s. bassani feeding in different locations in this region of southern Australia, rather than the single homogeneous population suggested by genetic studies.

Simulation of the solar adsorption refrigeration operating at near atmospheric pressure

To solve the leaking problem faced by current vacuum adsorption refrigeration systems, the authors have carried out a series of studies on the concept of raising the system's pressure to around atmospheric pressure with an inert gas (eg. Helium) as the pressure-adjusting agent. This paper presents the simulation of the performance oj the activated carbon-methanol adsorption refrigeration operating at near atmospheric pressure powered by solar energy. This simulation can be refereed in the prototype design.

Machine to die for: the quest for free energy

This is about the search for 'perpetual motion' and 'free energy'. Conventional science claims that it is impossible, yet generations of inventors have been mesmerised by the promise of an engine that powers itself. The world's reliance on diminishing fossil fuel resources and the associated problems of pollution serve to spur them on. It showcases a number of dedicated, sometimes eccentric, and always obsessive individuals who have devoted their lives to this quest.

Water repellency, near-saturated infiltration and preferential solute transport in a macroporous clay soil

Little attention has been paid to the possibility that soil water repellency could enhance non-equilibrium water flow and solute transport through macropores present in structured clay soils. In this study, we measured infiltration and solute transport in a clay soil under near-saturated conditions in both the field using tension infiltrometers and in the laboratory on undisturbed soil columns. Measurements were made on adjacent plots under grass and continuous arable cultivation. Steady-state field infiltration rates measured using water and ethanol as the infiltrating fluids demonstrated that the soil macroporosity under grass was better developed, but that much of the structural pore system was inactive due to water repellency. No water repellency was detected on the arable plot disturbed by tillage. Dye tracing showed that the conducting macroporosity was largely comprised of earthworm channels in the grassed plot and inter-aggregate voids resulting from ploughing in the arable plot. Tracer breakthrough curves measured on field-dry soil indicated rapid macropore transport in columns taken from both plots, although the degree of non-equilibrium transport appeared somewhat stronger under grass. This result, which was attributed to water repellency, was also consistent with the larger flow-weighted mean pore size found in the field infiltration experiments. It is concluded that water repellency in undisturbed structured clay soils can have significant effects on the occurrence of non-equilibrium water and solute transport in macropores.

Assessing indicant directionality of a media consumption construct using confirmatory tetrad analysis

When assessing the psychometric properties of measures and estimate relations among latent variables, many studies in the social sciences (including marketing) often fail to comprehensively appraise the directionality of indicants. Such failures can lead to model misspecification and inaccurate parameter estimates (Jarvis et al. 2003). In order to further assess the correct directionality of a ‘media consumption’ construct’s indicants, this paper employs confirmatory tetrad analysis (CTA). Previous studies advocate this construct being best viewed as formative. However, our CTA suggests it could be modelled using a reflective orientation. We then conclude the paper drawing recommendations for future studies advocating that when assessing item directionality researchers should implement pre and post hoc tests.

Library of the seven selves

Jarvis’s thesis is a study of libraries as they are represented in art and literature. It analyses the way libraries serve to control and direct knowledge, while also considering the extent to which the creative imagination, in building habitable spaces within which poetic moments can occur, offers resistance.