144 resultados para White-crowned Sparrows

em Deakin Research Online - Australia


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Garden warblers (Sylvia borin) were subjected to starvation trials during their autumnal migratory phase in order to simulate a period of non-stop migration. Before, during and after this treatment the energy expenditure, activity, food intake and body mass of the subjects were monitored. Assimilation efficiency was constant throughout the experiments. The catabolized (during starvation) and deposited body tissue (during recovery) consisted of 73% fat. Basal metabolic rate was decreased during the starvation period and tended to a gradual increase during the recovery period. The reduced basal metabolic rate can possibly be attributed to a reduced size/function of the digestive system, which is consistent with the sub-maximal food intake immediately after resuming the supply of food to the experimental birds. The observed reductions in basal metabolic rate during starvation and activity during recovery can be viewed as adaptations contributing to a higher economization of energy supplies. The experimental birds were unable to eat large quantities of food directly after a period of starvation leading to a comparatively low, or no increase in body mass. Such a slow mass increase is in agreement with observations of migratory birds on arrival at stop-over sites.

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As a result of negative net immigration during the 1890s depression, Australians at the time of Federation were preoccupied about the slow rate of growth of the population. The non-Aboriginal population at the end of 1904 was approximately three and three-quarter million. and the publication in March 1904 of the Report of the New South Wales Royal Commission on the Decline of the Birth Rate and the Mortality of Infants did nothing to allay these concerns. Despite the perceived need for more people. the desire for racial unity was paramount. The main goals of policy makers at the time were to preserve a 'white' and essentially British Australia and create an imperial bastion in the Southern Hemisphere.

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Over time, the Immigration Restriction Act of 1901 and its later amendments were remarkably successful in excluding 'coloured' immigrants from Australia.  It is clear, however, that although most Australians wanted to preserve the 'white' and British character of their nation, the argument that 'non-white' and non-British immigrants were more suited to the settlement of northern Australia was frequently debated in the early decades of the twentieth century.  While this idea continued to challenge the validity of a 'white Australia' in the north, public figures were divided on the issue.  This article examines in some detail the contemporary debates over the peopling of the Northern Territory in the inter-war years.

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The performance of a strip search by a police officer is a serious interference with the liberty and dignity of an individual. However, it is considered by police to be an important part of their law enforcement armory and one that is increasingly necessary to utilise to assist in the investigation and prosecution of drug-related crimes. This article considers the troublesome issue of whether and in what circumstances the common law may extend to police the power to conduct a strip search. In addition, there is an examination of the statutes and regulations that purportedly give police in Victoria the power to strip search with particular attention given to ss 81 and 82 of the Drugs, Poisons and Controlled Substances Act 1981 (Vic).

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The aim of this study was to examine the demographic, health habits and personal values associations of white bread use. A total of 474 randomly selected consumers completed a questionnaire about bread consumption, health habits and personal values. The findings showed that compared with non-consumers white bread users were younger, less educated, more likely to have children and to be smokers. They were less likely to follow vegetarian, low fat or special diets or use alternative therapies. Non-consumers were more likely to hold pro-nature universalistic values. This suggests that the use of this staple food is associated with demographic, behavioural and ideological domains. Their causal inter-relationships require further investigation.

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Considerable progress has been made in understanding the molecular basis of normal white blood cell development and its perturbation in disease through the use of clinical studies and traditional animal and cell line models. Despite this, however, many questions are still being answered and white blood cell disorders, including leukemia and lymphoma, remain a significant health problem. The zebrafish (Danio rerio) has emerged as a powerful alternative vertebrate model for the study of development and disease. We review the recent application of zebrafish to the study of white blood cell development and its disruption, particularly leukemogenesis. Such studies have highlighted the overall conservation of these processes throughout vertebrates, and establish zebrafish as a useful experimental model. This organism is now poised to make an important contribution to our understanding of the underlying genetic control of white blood cell development and its disruption, as well as the identification of new therapeutic agents.

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The White-faced Storm Petrel (Pelagodroma marina) is restricted to three breeding colonies within Victoria: Mud Islands and South Channel Fort in Port Phillip Bay, and Tullaberga Island off Mallacoota. Numbers of these storm petrels breeding on Mud Islands have declined considerably since early last century. White-faced Storm Petrels were recorded on Mud Islands from early September 2002 until mid-March 2003 when the last chicks fledged. Eggs were laid from late October to early December, with chicks hatching in the later half of December. The mean incubation period was 51.7 days (± 3.2 days (s.d.), range = 38–53, n = 13), and may have been extended by periods of egg neglect. The mean nestling period was 54.8 days (± 4.4 days (s.d.), range 50–70, n = 21). Chick growth is described. Hatching success was 54% and fledging success was 77.8%, with overall breeding success being 42%. Burrow densities were found to be influenced by plant species, vegetation height and soil moisture. The position of the burrow within the colony was shown to influence breeding success, with those nearer the edge of the storm petrel colony, closer to the marsh, and further from a colony of Australian White (Threskiornis molucca) and Straw-necked (T. spinicollis) Ibis recording higher success.