50 resultados para Threat categories

em Deakin Research Online - Australia


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Conservationists are increasingly interested in determining the threat status of ecological communities as a key part of their planning efforts. Such assessments are difficult because of conceptual challenges and a lack of generally accepted criteria. We reviewed 12 protocols for assessing the threat status of communities and identified conceptual and operational issues associated with developing a rigorous, transparent, and universal set of criteria for assessing communities, analogous to the International Union for Conservation of Nature (IUCN) Red List standards for species. We examined how each protocol defines a community and its extinction and how each applies 3 overarching criteria: decline in geographic distribution, restricted geographic distribution, and changes to ecological function. The protocols vary widely in threshold values used to assess declines and distribution size and the time frames used to assess declines, leading to inconsistent assessments of threat status. Few of the protocols specify a scale for measuring distribution size, although assessment outcomes are highly sensitive to scale. Protocols that apply different thresholds for species versus communities tend to require greater declines and more restricted distributions for communities than species to be listed in equivalent threat categories. Eleven of the protocols include a reduction in ecological function as a criterion, but almost all assess it qualitatively rather than quantitatively. We argue that criteria should be explicit and repeatable in their concepts, parameters, and scale, applicable to a broad range of communities, and address synergies between types of threats. Such criteria should focus on distribution size, declines in distribution, and changes to key ecological functions, with the latter based on workable proxies for assessing the severity, scope, and immediacy of degradation. Threat categories should be delimited by thresholds that are assessed at standard scales and are logically consistent with the viability of component species and important ecological functions.

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 An understanding of risks to biodiversity is needed for planning action to slow current rates of decline and secure ecosystem services for future human use. Although the IUCN Red List criteria provide an effective assessment protocol for species, a standard global assessment of risks to higher levels of biodiversity is currently limited. In 2008, IUCN initiated development of risk assessment criteria to support a global Red List of ecosystems. We present a new conceptual model for ecosystem risk assessment founded on a synthesis of relevant ecological theories. To support the model, we review key elements of ecosystem definition and introduce the concept of ecosystem collapse, an analogue of species extinction. The model identifies four distributional and functional symptoms of ecosystem risk as a basis for assessment criteria: a) rates of decline in ecosystem distribution; b) restricted distributions with continuing declines or threats; c) rates of environmental (abiotic) degradation; and d) rates of disruption to biotic processes. A fifth criterion, e) quantitative estimates of the risk of ecosystem collapse, enables integrated assessment of multiple processes and provides a conceptual anchor for the other criteria. We present the theoretical rationale for the construction and interpretation of each criterion. The assessment protocol and threat categories mirror those of the IUCN Red List of species. A trial of the protocol on terrestrial, subterranean, freshwater and marine ecosystems from around the world shows that its concepts are workable and its outcomes are robust, that required data are available, and that results are consistent with assessments carried out by local experts and authorities. The new protocol provides a consistent, practical and theoretically grounded framework for establishing a systematic Red List of the world’s ecosystems. This will complement the Red List of species and strengthen global capacity to report on and monitor the status of biodiversity.

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Cricket umpires, cricket bowlers, and physical education students (who were knowledgeable about the rules of cricket), were shown 72 videotaped point-light displays of cricket deliveries with varying extents of elbow flexion such that they ranged from highly “bowl-like” to highly “throw-like”. The observers made a bowl-throw decision about each display, and the umpires and bowlers reported their confidence on a 5-point scale. The percentage of displays reported as a “bowl” was 59, 40, and 44 for the umpires, bowlers, and students respectively. Umpires made significantly more bowl decisions than both the bowlers and students, but there was no difference between the latter groups. Umpires were significantly more confident than the bowlers in both their bowl and throw decisions. Thus, in an experimental setting, with no apparent costs or benefits associated with their decision-makin, umpires “called” a bowler significantly less frequently for throwing than other knowledgeable observers. The procedures devised for this experiment demonstrate that psychophysical methods can be applied to the problem of discrete action-category nominations in sport (e.g., bowl or throw, walk or run).

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An involvement-commitment-loyalty model is proposed and tested with AMOS. The results for fast-moving-consumer-goods (fmcg) are consistent with the theory. Ego involvement influences purchase involvement, which influences brand commitment, which influences customer loyalty. The results for the more ego-involved service of hair stylists, however, showed a different result. Purchase loyalty did not mediate the relationship between ego involvement and brand commitment, but instead ego involvement had a direct relationship with brand commitment.

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BACKGROUND: Effective public policy requires information on the prevalence of overweight and obesity. OBJECTIVE: We determined changes in the population prevalence of overweight and obesity among young Australians (aged 7-15 y) from 1969 to 1985 to 1997. DESIGN: Data from 5 independent population surveys were analyzed: the Australian Youth Fitness Survey, 1969; the Australian Health and Fitness Survey, 1985; the South Australian Schools Fitness and Physical Activity Survey, 1997; the New South Wales Schools Fitness and Physical Activity Survey, 1997; and the Health of Young Victorians Study, 1997. Measured body mass index was used as the index of adiposity, and recently published body mass index cutoff values were used to categorize each subject as nonoverweight, overweight, obese, or either overweight or obese. RESULTS: For 1985-1997, the population prevalence of overweight increased by 60-70%, obesity increased 2-4-fold, and the combined overweight and obesity categories doubled. The findings were consistent across data sets and between the sexes. For 1969-1985, there was no change in the prevalence of overweight or obesity among girls, but among boys the prevalence of overweight increased by 35%, the prevalence of obesity trebled, and the prevalence of overweight and obesity combined increased by 60%. CONCLUSIONS: The data show that in 1985-1997, the prevalence of overweight and obesity combined doubled and that of obesity trebled among young Australians, but the increase over the previous 16 y was far smaller. These results should increase our sense of urgency in identifying and implementing effective responses to this major threat to public health.

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The central proposition of motivational posturing theory is that regulatees place social distance between themselves and authority, communicating the nature of that distance through a narrative that protects the self from negative appraisal by the authority. One of the key components of posturing is the coping sensibility that individuals adopt to manage the threat of authority. At a baseline level, authorities make demands on citizens and as such threaten individual freedom. At the highest level, authorities threaten through punishment for non-compliance. Data collected from 3,253 randomly selected Australian taxpayers and a special group of 2,292 taxpayers in conflict with the tax authority are used to show that in both groups, three coping sensibilities contribute to posturing ("thinking morally,""feeling oppressed," and "taking control"), and that all three sensibilities are significantly heightened in the group experiencing conflict with the authority. The article argues that the most effective regulatory outcome is achieved when the regulatory process can dampen the "taking control" and "feeling oppressed" sensibilities, and strengthen the "thinking morally" sensibility. Responsive regulation is an approach that encourages tax authorities to read motivational postures, understand the sensibilities that shape them, and tailor a regulatory intervention accordingly.

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This research reported in this paper tested the composition of the brand knowledge construct across three product categories. The brand knowledge construct was tested for a fast-moving consumer good (fmcg), a service, and a durable good. A quasi-experimental method was utilised, with the order of recall manipulated. Respondents undertook a free recall exercise using category cues, and then completed multi-item measures of brand knowledge. This exercise was repeated for each product category. A usable sample of 270 responses was gained. Analysis of the data found that respondents utilised different components of the knowledge construct depending on the product category being recalled. In addition, the order of recall (fmcg or durable first) affected the recall performance for later categories. Recall performance was highest for the durable category, which indicated that respondents may have been delving into different memory stores, and accessing long-term memory for durable good recall. This paper makes a contribution to the field of branding by providing a test of the knowledge structure across three product categories, and indicating the components that contribute to knowledge for each category. These findings have implications for advertising design, and the formation of links to brands in memory by advertisers, for use in later recall episodes.

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This paper presents a system of systems approach to threat detection through integration of heterogeneous independently operable systems. The approach is presented on a realistic situation where a human-controlled base robot, swarm robot(s), and sensors work together to obtain a decision about a possible threat in the environment. The base robot is remotely operated by a human using a haptic control system. The swarm robot(s) are autonomous and can accept directives from the base robot. Finally, sensors directly communicate with (report to) the base robot. In this scenario, heterogeneous systems and human interact in a system of systems architecture. With the inclusion of human expert and sensor verification of swarm robots, the system can successfully perform the threat detection and reduce the false alarms. Finally, a system of systems simulation framework including a base robot, a swarm robot, and two sensors is presented in addition to an experimental evaluation of the proposed SoS architecture

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Argues that the "China threat" argument in mainstream international relations literature in the United States is derived, primarily, from a discursive construction of otherness. Construction which is predicated on a particular narcissistic understanding of the U.S. self and on a positivist-based realism, concerned with absolute certainty and security; Concern which is central to the dominant U.S. self-imagery.

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"Since the end of the Cold War, one of the most significant debates in international relations has been the question of whether the rise of China as a major economic, political and military power will be a force for stability or instability in the international system and the East Asian region. Forceful arguments have been put forward on both sides."
"This book examines perceptions of the 'China Threat', and governments' policies in response to the perceived threat in a wide range of countries, including the United States, Russia, Europe, Japan, South Asia, South-East Asia and the Middle East, as well as the perceptions of the Chinese themselves. For each country current security concerns and policies, especially the policy of engagement, are examined in detail, and future prospects for relations with China are assessed. As the Bush administration in Washington increasingly focuses on China as a 'strategic competitor' and Sino-US-relations become increasingly tense, the 'China Threat' issue has come to dominate the security agenda in the Asia-Pacific region, and now poses the biggest foreign policy challenge of the twenty-first century."

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The soil-borne plant pathogen Phytophthora cinnamomi occurs in most Australian states. It is pathogenic to many Australian species, particularly the Proteaceae, Fabaceae, Dillineaceae and Epacridaceae. In Western Australia, c. 2000 of the 9000 endemic plant species are directly affected by the disease. The epidemic of plant deaths caused by P. cinnamomi is recognised as one of 11 Key Threatening Processes to the Australian Environment, and is now also acknowledged as a potential threat fauna in a range of communities. The implications of landscape modification due to the effects of P. cinnamomi dieback prompted our research, designed to measure the distribution and abundance of small mammals in disease-affected ecosystems. This study was in the Jarrah (Eucalyptus marginata) forests in the Darling Range, Western Australia and measured the distribution and abundance of one small mammal species, the Mardo (Antechinus flavipes) by Elliott trapping in forests with (1) high, (2) mixed and (3) no evidence of Phytophthora dieback. Trap success was highest in sites with no effect of Phytophthora (7.3 animals per 100 trap nights), whereas the lowest trap success was recorded at the high impact sites (0.67 animals per 100 trap night). There was a significant difference in trap success of Mardos in Elliott trapping over 1800 trap nights (x2= 23.19, d.f = 5, p < 0.001). An examination of the distribution of individuals and sexes suggests that Phytophthora-affected sites act as sinks for Mardos, while source areas are healthy, unaffected Jarrah forest.

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Stream insects use a variety of refuges to survive drought that vary in their vulnerability to water extraction. We surveyed drought refuges in 16 ephemeral streams with different flow regimes. Perennial sections were the most important drought refuge, but are the most likely to disappear when water is extracted.