27 resultados para Field evidence
em Deakin Research Online - Australia
Resumo:
Whilst a range of animals have been shown to respond behaviourally to components of the Earth’s magnetic field, evidence of the value of this sensory perception for small animals advected by strong flows (wind/ocean currents) is equivocal. We added geomagnetic directional swimming behaviour for North Atlantic loggerhead turtle hatchlings (Caretta caretta) into a high-resolution (1/4°) global general circulation ocean model to simulate 2,925-year-long hatchling trajectories comprising 355,875 locations. A little directional swimming (1–3 h per day) had a major impact on trajectories; simulated hatchlings travelled further south into warmer water. As a result, thermal elevation of hatchling metabolic rates was estimated to be between 63.3 and 114.5% after 220 days. We show that even small animals in strong flows can benefit from geomagnetic orientation and thus the potential implications of directional swimming for other taxa may be broad.
Resumo:
For free‐spawning organisms that release gametes into the sea, sperm limitation (too few sperm to fertilize all eggs) is a major factor limiting reproductive success. Given such circumstances, the presence of several mechanisms to prevent polyspermy (too many sperm) may seem paradoxical; however, a growing body of data suggests that natural fertilization levels, though variable, can routinely be high. Under such conditions, polyspermy is much more likely. The tension between sperm limitation and polyspermy represents sexual conflict because males, in competing to fertilize as many eggs as possible, can impose lethal costs on eggs if multiple sperm gain entry. Here we present data for a marine invertebrate indicating high levels of polyspermy under sperm‐limited conditions. When the sea urchin Evechinus chloroticus was induced to spawn in situ, mean rates of polyspermy were 17.3% ±3.4%, and polyspermy was recorded at rates as high as 62.7%. Polyspermy was nearly always present, even when fertilization rates were <50%, confirming predictions that it should be present under sperm‐limited conditions. Both sperm limitation and polyspermy imposed substantial reproductive costs, and we conclude that both sexual conflict related to polyspermy and sperm limitation have been simultaneous strong selective forces shaping the evolution of reproductive traits in the sea.
Resumo:
Detrimental effects of diversity in workgroups has frequently been observed but research identifying the factors that lead to negative or positive effects in heterogeneous groups is lacking. The perceived dissimilarity openness moderator model provides one explanation of the process by which diversity influences group affective, behavioral, and cognitive outcomes. Specifically the model identifies individual, group, and organizational openness as moderating the effects of diversity in workgroups. In this paper evidence is provided from a field study that increased openness to perceived dissimilarity leads to better outcomes in newly formed groups. This study also constitutes a significant building block toward the development of theory concerning the moderating variables of the relationship between diversity and group processes, and outcomes of organizations.
Resumo:
Explanations of the origin and genesis of Pacific field monuments commonly assume they reflect local social change in islands or island groups which were increasingly isolated following colonization. A recent review of early West Polynesian archaeology suggests that the penecontemporaneous appearance of various kinds of field monuments from eastern Melanesia to Polynesia may be better explained as evidence of interaction and the movement of people and/or ideas, possibly associated with the colonization of East Polynesia.
Resumo:
There is accumulating evidence that body and mind, or rather the physical and the non-physical, are intrinsically connected. The mechanisms through which reality therapy works on mind and body may be explained via positive dynamics in the central nervous system, the body's biochemistry and the human energy field. The purpose of this paper is to show the relationship between choice theory and the nature of the power centers in the human energy field. Understanding the drivers behind human behavior and facilitating the choice to think realistically and to make responsible choices assists wholeness and enhances the physical, mental and spiritual health.
Resumo:
The aim of this paper is to assess and reflect on, through the perspectives of Australian Quality practitioners, the current status of quality management; whether there had been any significant and recent shift in their roles and responsibilities; and if there had been any improvement in the extent to which their development and training needs were being fulfilled. This paper sets out to identify the roles, responsibilities, and training and development needs of Australian quality managers and what impact these may be having on the current 'quality agenda' of organisations in Australia. In light of these findings this paper focuses on the HR people aspects of QM implementation (e.g. development of a quality culture; learning, training and development; leadership and management commitment and support) and the significance of these aspects for sustainable QM implementation. Recent literature On QM implementation and the findings of three previously conducted surveys (Waddell 1998; Waddell and Mallen 2001; and Stewart and Waddell 2003) have been integrated with the findings of this research.
Resumo:
This study examines the current status of cross-cultural management (CCM) in Australia.
The study is based on Reyes' (2004) Ph.D research of a qualitative nature in five organisations in the public and private sectors selected from a sample of organisations which appear to lead the field in Australia in respect of CCM. Literature is also surveyed to present a picture of the current legal and institutional setting of CCM in Australia and provide a context for the study.
Analysis of the findings highlights the gap between cross-cultural rhetoric and action in workplace situations. Problems are identified leading to incomplete and inadequate implementation of CCM in the respondent organisations. The study argues for the need for management to take a systems approach to the formulation and implementation of CCM. Some suggestions are made for improvements in the future.
Resumo:
Purpose – The purpose of this article is to present an empirical analysis of complex sample data with regard to the biasing effect of non-independence of observations on standard error parameter estimates. Using field data structured in the form of repeated measurements it is to be shown, in a two-factor confirmatory factor analysis model, how the bias in SE can be derived when the non-independence is ignored.
Design/methodology/approach – Three estimation procedures are compared: normal asymptotic theory (maximum likelihood); non-parametric standard error estimation (naïve bootstrap); and sandwich (robust covariance matrix) estimation (pseudo-maximum likelihood).
Findings – The study reveals that, when using either normal asymptotic theory or non-parametric standard error estimation, the SE bias produced by the non-independence of observations can be noteworthy.
Research limitations/implications – Considering the methodological constraints in employing field data, the three analyses examined must be interpreted independently and as a result taxonomic generalisations are limited. However, the study still provides “case study” evidence suggesting the existence of the relationship between non-independence of observations and standard error bias estimates.
Originality/value – Given the increasing popularity of structural equation models in the social sciences and in particular in the marketing discipline, the paper provides a theoretical and practical insight into how to treat repeated measures and clustered data in general, adding to previous methodological research. Some conclusions and suggestions for researchers who make use of partial least squares modelling are also drawn.
Resumo:
This study explores the issue of internationalization through forming alliances with foreign capital in the small business sector in Turkey. Using a sample of 257 SMEs from this emerging market economy, collected via a field study, it finds that Turkish SMEs would like to form alliances with foreign capital for expanding their production capacity and accessing to world markets. Multivariate multinomial logit models are employed to analyse the survey data econometrically. Size-specific, sector-specific and management-specific factors are identified in the alliance motivation. The `market' and `finance' aspects of alliances prevail in the multivariate analysis with significant implications. There is also evidence that some conditional relationships offered by multivariate analysis differ from unconditional associations found in the survey, which implies that alliance motivation is partly a product of multidimensional decision-making process on behalf of SMEs.
Resumo:
It has become common in the literature to compare India and China, two remarkably growing economies, but these comparisons often do not take into account the institutional differences between these two countries. We have in this paper done a comparative analysis of banking institutions in China and India taking into accounts the contentious issue of nonperforming loans along with the issue of use of banks to provide countervailable subsidies to exporting organizations. Our research shows that the efficiency differences between banks in these two countries can be directly related to institutional difference and any comparative study between these countries not taking into consideration these institutional differences may lead to misleading results.
Resumo:
Marsupial neonates are born without a fully functioning immune system, and are known to be protected in part by natural antimicrobial peptides present in their mother's milk. Monotreme neonates hatch at a similar stage in development, and it has been hypothesised that their survival in a non-sterile burrow also relies on the presence of natural antibiotics in their mother's milk. Here we review the field of monotreme lactation and the antimicrobial peptide complement of the platypus (Ornithorhynchus anatinus). Using reverse transcriptasepolymerase chain reaction of milk cell RNA from a sample of platypus milk, we found no evidence for the expression of cathelicidins or defensins in the milk. This was unexpected. We hypothesise that these natural antibiotics may instead be produced by the young platypuses themselves.
Resumo:
There is an expanding field of research investigating the benefits of alternatives to current pharmacological therapies in psychiatry. N-acetylcysteine (NAC) is emerging as a useful agent in the treatment of psychiatric disorders. Like many therapies, the clinical origins of NAC are far removed from its current use in psychiatry. Whereas the mechanisms of NAC are only beginning to be understood, it is likely that NAC is exerting benefits beyond being a precursor to the antioxidant, glutathione, modulating glutamatergic, neurotropic and inflammatory pathways. This review outlines the current literature regarding the use of NAC in disorders including addiction, compulsive and grooming disorders, schizophrenia and bipolar disorder. N-acetylcysteine has shown promising results in populations with these disorders, including those in whom treatment efficacy has previously been limited. The therapeutic potential of this acetylated amino acid is beginning to emerge in the field of psychiatric research.
Resumo:
There is paucity of data regarding hydrocarbon exposure of tropical fish species inhabiting the waters near oil and gas platforms on the Northwest Shelf of Australia. A comprehensive field study assessed the exposure and potential effects associated with the produced water (PW) plume from the Harriet A production platform on the northwest shelf in a local reef species, Stripey seaperch (Lutjanus carponotatus). This field study was a continuation of an earlier pilot study which concluded that there were “warning signs” of potential biological effects on fish populations exposed to PW. A 10-day field caging study was conducted deploying 15 individual fish into 6 separate steel cages set 1-m subsurface at 3 stations in a concentration gradient moving away from the platform. A battery of biomarkers were evaluated including hepatosomatic index (HSI), total cytochrome P450, bile metabolites, CYP1A-, CYP2K- and CYP2M-like proteins, cholinesterase (ChE) activity, and histopathology of liver and gill tissues. Water column and PW effluent samples was also collected. Results confirmed that PAH metabolites in bile, CYP1A-, CYP2K-, and CYP2M-like proteins and liver histopathology provided evidence of significant exposure and effects after 10 days at the near-field site (~200 m off the Harriet A platform). Hepatosomatic index, total cytochrome P450, and ChE did not provide site-specific differences by day 10 of exposure to PW. CYP proteins were shown by principal component analysis (PCA) to be the best diagnostic tool for determining exposure and associated biological effects of PW on L. carponotatus. Using a suite of biomarkers has been widely advocated as a vital component in environmental risk assessments worldwide. This study demonstrates the usefulness of biomarkers for assessing the Harriet A PW discharge into Australian waters with broader applications for other PW discharges. This approach has merit as a valuable addition to environmental management strategies for protecting Australia’s tropical environment and its rich biodiversity.