On the rate of crack extension due to transverse shear fatique loading

During the period of crack initiation, extremely small microcracks form. The fatigue life of any structure may be divided into three distinct subdivisions: crack initiation, crack growth, and total failure. The principal objective of this thesis is the design of a simple machine that may be used in the study of growth phenomena of a small crack in an aluminum plate due to a transverse shear fatigue load

Food Resources of Carnaby’s Black-Cockatoo (Calyptorhynchus latirostris) in the Gnangara Sustainability Strategy study area

Carnaby’s Black-Cockatoo is an endangered species, with less than 50% of the original population remaining (Garnett and Crowley 2000). A major threatening process includes habitat fragmentation and the removal of critical feeding resources (Cale 2003). The GSS study area in an important foraging area during the non-breeding season for Carnaby’s Black-Cockatoo. Both native banksia woodlands and pine plantations have been recognised as an important food resource (Perry 1948; Saunders 1974b; Saunders 1980). Expanding urban populations and agricultural development has resulted in the removal of approximately 50% of native vegetation in the GSS study area. Within the remnant vegetation, the energetics, occurrence and densities of principal native food sources (e.g. Banksia attenuata) is still largely unknown, but varies depending on soil type, vegetation complex and fire history (Heddle et al. 1980; Scott and Black 1981; Valentine and Stock unpublished data). In addition, there are a number of limitations with the existing data, and further research is required to accurately estimate the availability of food resources. The predicted removal without replacement of the pine plantations is expected to impact on Carnaby’s Black-Cockatoo (Cale 2003; Garnett and Crowley 2000). The amount of food resources in the GSS pine plantations currently available to Carnaby’s Black- Cockatoo is predicted to be able to support over 10,000 birds for a 6 month period (with a prior mentioned caveats). If preliminary foraging behaviour data is incorporated, it is likely that the pine plantation will support approximately 2,800 birds for a 6 month period. Food resources in remnant Banksia attenuata habitat in the GSS study area vary depending on the landform and year since last burn (Valentine and Stock, unpublished data). The combined area of Bassendean North and Cottesloe North vegetation complexes (~ 25,000 ha) within DEC estate in the GSS study area could provide the minimum requirement of food for a maximum of approximately 18,500 birds for a 6 month period. However, incorporating preliminary foraging behaviour data reduces this estimate to approximately 4,900 birds for a 6 month period. The pine plantations provide an enormous food resource for Carnaby’s Black-Cockatoos. Regardless of the availability of native food sources, removing this amount of resource will affect Carnaby’s Black-Cockatoo in some manner. Assuming the remnant vegetation provides sufficient food resources for Carnaby’s Black-Cockatoos, the birds may simply switch foraging behaviours and diets to principally native species. However, if native food availability is limited, the removal of pine plantations may have greater impacts. Birds may search elsewhere for food during the non-breeding season, possibly switching diets to commercial agricultural crops (e.g. canola), and the populations on the Swan Coastal Plain may dwindle. In addition, if food is limited during the non-breeding season, birds may starve or enter the breeding season in poor condition, which is likely to affect breeding success, and ultimately population growth. Our review and preliminary research reinforces the importance of food resources on the Swan Coastal Plain (from both banksia woodlands and pine plantations), and highlights the urgent need to more accurate research into the availability of food resources and foraging ecology of Carnaby’s Black-Cockatoo

Pines and the ecology of Carnaby‘s Black-Cockatoos (Calyptorhynchus latirostris) in the Gnangara sustainability strategy area

This study examined the behavioural ecology of Carnaby‘s Black-Cockatoo in the Gnangara Sustainability Strategy study area, with a focus on habitat use of pine plantations. The study confirms that the pine is the main food source for Carnaby‘s Black-Cockatoos within the GSS area during the non-breeding season (January-June). The value of the Gnangara-Pinjar-Yanchep pine plantations as a food source for Carnaby‘s Black-Cockatoo should not be underestimated. Large congregations of birds (~3000) utilised the pine plantations for an extended period, mainly January-March but with birds continuing to feeding within the plantations through June. The pine plantations have provided an important and dependable feeding habitat since the 1940s, a period that has seen the abundance of this species decline by at least 50% and its range contract by one-third. The impact of pine removal should also be considered within a suite of broader changes to the GSS landscape. These changes include the loss of feeding habitats off-plantation (e.g. thickets of Banksia sessilis around Neerabup and within the Northwest Corridor) and predictions of declining productivity within areas of Banksia woodland due to reduced rainfall and the spread of dieback, Phytophthora cinnamomi. There is uncertainty about whether the remnant native vegetation in the GSS area will provide an adequate food source following the removal of pine plantations, particularly from January to March when feeding within the plantations is most intensive. This topic requires further investigation. In April and May 2009 (‗dryandra period), at least 4000 birds were concentrated between Neerabup and Boongarra as large aggregations form to feed within thickets of Banksia sessilis. These aggregations probably draw together flocks that through February and March had been feeding: (a) in and around the GSS pine plantations; (b) in the suburban areas to the south and west of the plantations; and (c) in areas to the north of Boongarra. When the dryandra feeding period is completed, the aggregations most likely broke apart again, with birds either returning to feed on pine again or in Banksia woodland areas. This also roughly coincides with the period when breeding birds will begin transitioning back to breeding habitats inland, and from June through August birds may mass into large flocks of several thousand as they shift away from feeding habitats on the Swan Coastal Plain. Large flocks have been observed in July and August around the northern end of the Yanchep plantation, suggesting that birds migrating to breeding sites to the north and east of the GSS area may aggregate in areas of the pine plantations where some food remains and/or the large areas of Banksia woodland. Not all adult birds breed each year, and some birds remain on the Swan Coastal Plain, and between 600-1500 birds are likely to be present within the GSS area during the non-breeding season Food availability in Banksia woodland habitats probably peaks in the late winter-spring period (August-November), since this is the season when the majority of Banksia species on the Swan Coastal Plain are flowering and the fruits of B. attenuata mature. It is unknown how much food remains available in the Banksia woodlands throughout the year, and this topic requires further research. Given the lack of information on the seasonal availability of food for this species, a precautionary conservation step would be the retention of some form of pine. Lower stand densities and larger breaks between stands would encourage greater canopy growth and thus greater production of cones, thereby compensating for an overall decrease in the area covered by pine. If full pine removal is effected, feeding habitat can be restored quickly and at relatively low cost through the seeding and/or planting of native and non-native food species that are well-adapted to growth in a high-disturbance environment. These species include: Banksia sessilis and similar Dryandras, Hakea spp., marri, Erodium, and Pinus spp. However, given the potential negative impacts of introduced species (e.g. Erodium) on other elements of biodiversity, the use of such species as food sources for Carnaby‘s Black-Cockatoo should be avoided. The provision of roosting habitat is a potentially over-looked function of pine, particularly in landscapes where there are few large trees to roost. Thus, restoration objectives for Carnaby‘s cockatoos could possibly be integrated into current strategies to create ecological corridors or be developed as offset measures. The key issues are the need to find suitable roost tree species and to replace feeding habitat that provides food in the January to April period, to compensate for the removal of roost sites and food from pine plantations. Further research is required to identify the potential carrying capacity of the remnant Banksia woodland following the removal of pine plantations. In particular, this research should identify availability of food (and watering points) during January – March

Cost-effectiveness of pioglitazone in type 2 diabetes patients with a history of macrovascular disease: a German perspective

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Finding new meaning for old values: Aboriginal cultural tourism planning in and adjacent to protected areas

My doctoral research with the Girringun Aboriginal Corporation on Country-based tourism planning and management in the Wet Tropics World Heritage Area explores applications of traditional knowledge within Aboriginal tourism and the real or imagined barriers to its recognition by the broader tourism industry and tourism managers as an essential linkage between Indigenous peoples and their environments. Education/tourism activities on Country may be one of the few ways to preserve knowledge as a lived-experience, as the culture surrounding traditional hunting and access to Country in protected areas evolves. This research has been strongly influenced by senior Jirrbal Elder, Ernie Grant, whose holistic planning and education framework has been adopted by the Queensland Department of Education as a model for cross-cultural education. His style of cultural education at Echo Creek can be viewed as a model of best-practice rainforest tourism, in which traditional knowledge, cultural transmission, and ecosystem and Indigenous wellbeing are indivisible. This holistic approach has the potential for broader application in developing participatory approaches to cultural awareness for a range of protected area stakeholders, including managers and the tourism industry

UV and blue light regulation of transcription of the chalcone synthase gene in Arabidopsis

In order to identify light responsive cis-acting DNA sequence elements of the Arabidopsis thaliana chalcone synthase gene (AtCHS) concerned with induction by UV-B and UV-A/blue light, we developed a UV/blue light inducible transient expression system. This system involved transfection of chimaeric AtCHS promoter constructs into Arabidopsis cell culture protoplasts. The reporter enzyme beta-glucuronidase (GUS) was used to monitor light responsive promoter activity. Development of this system involved defining and optimising procedures for preparing protoplasts from the Arabidopsis cell culture, transfection of chimaeric AtCHS promoter constructs into the protoplasts and incubation under defined illumination conditions. An efficient homologous protoplasts transient expression system was developed which subsequently enabled us to undertake functional analysis of the AtCHS promoter. Application of the transient expression system allowed us to define the light responsive cis-acting elements concerned with the transcriptional activation of AtCHS. This analysis showed that a 1972 bp promoter conferred UV-B and UV-A/blue light induction of GUS activity. Deletion of the promoter to 164 bp resulted in reduced promoter strength but retention of responsiveness to UV-B and UV-A/blue light. Further deletion abolished transcriptional activity. The 164 bp promoter contains sequences closely resembling the light-responsive unit (LRUPcCHS) of the Petroselinum crispum CHS promoter. This Arabidopsis CHS promoter region, designated LRUPcCHS, was sufficient to confer UV-B and UV-A/blue light responsiveness to a heterologous core promoter. Mutation of sequences in corresponding to the ACGT element and the MYB recognition element of LRUPcCHS resulted in inactivation of 164 bp and 335 bp promoter deletions. However, the mutant 668 bp promoter retained residual UV-B and UV-A/blue light-induced expression, indicating the presence of additional functional sequences upstream of -335. Mutation of a single G-box-like sequence around -442 had no effect on light responsiveness, indicating that it does not function in the light regulation of this promoter. Furthermore, in this analysis no difference in responsiveness to UV-B and UV-A/blue light was observed with any promoter variant tested. This suggests that the UV-B and the UV-A/blue phototransduction pathways regulate transcription factors which interact with common promoter elements. These results are discussed. We employed several different approaches to investigate the role of cryptochromes in the regulation of AtCHS promoter activity. Gain of function transient expression analysis suggests that CRY1 is the primary photoreceptor mediating UV- A/blue light induction of promoter activity. In addition, northern analysis using various cryptochrome mutant lines, including a cry1/cry2 double mutant, supports this hypothesis and, furthermore, suggests that (an)other photoreceptor(s) able to respond to UV-A/blue light, exist in Arabidopsis. Possible reasons for these observations are discussed. We used the transient expression system to investigate the role of sugar regulation in the control of AtCHS promoter activity in Arabidopsis protoplasts. This revealed that sucrose, glucose or fructose was required to stimulate AtCHS promoter activity. Furthermore, studies using glucose analogues were performed which suggest that the initial signal for sugar stimulation of AtCHS promoter activity is consistent with signalling by hexokinase phosphorylation of hexose sugars. Evidence for this hypothesis is discussed. (Abstract shortened by ProQuest.)

Hydrogen production by methanogens under low-hydrogen conditions

Hydrogen production was studied in four species of methanogens (Methanothermobacter marburgensis, Methanosaeta thermophila, Methanosarcina barkeri, and Methanosaeta concilii) under conditions of low (sub-nanomolar) ambient hydrogen concentration using a specially designed culture apparatus. Transient hydrogen production was observed and quantified for each species studied. Methane was excluded as the electron source, as was all organic material added during growth of the cultures (acetate, yeast extract, peptone). Hydrogen production showed a strong temperature dependence, and production ceased at temperatures below the growth range of the organisms. Addition of polysulfides to the cultures greatly decreased hydrogen production. The addition of bromoethanesulfonic acid had little influence on hydrogen production. These experiments demonstrate that some methanogens produce excess reducing equivalents during growth and convert them to hydrogen when the ambient hydrogen concentration becomes low. The lack of sustained hydrogen production by the cultures in the presence of methane provides evidence against "reverse methanogenesis" as the mechanism for anaerobic methane oxidation