188 resultados para ORIGINS


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The mineral geminite, an hydrated hydroxy-arsenate mineral of formula Cu(AsO3OH)•H2O, has been studied by Raman and infrared spectroscopy. Two minerals from different origins were investigated and the spectra proved quite similar. In the Raman spectra of geminite, four bands are observed at 813, 843, 853 and 885 cm-1. The assignment of these bands is as follows: (a) The band at 853 cm-1 is assigned to the AsO43- ν1 symmetric stretching mode (b) the band at 885 cm-1 is assigned to the AsO3OH2- ν1 symmetric stretching mode (c) the band at 843 cm-1 is assigned to the AsO43- ν3 antisymmetric stretching mode (d) the band at 813 cm-1 is ascribed to the AsO3OH2- ν3 antisymmetric stretching mode. Two Raman bands at 333 and 345 cm-1 are attributed to the ν2 AsO4 3- bending mode and a set of higher wavenumber bands are assigned to the ν4 AsO43- bending mode. A very complex set of overlapping bands is observed in both the Raman and infrared spectra. Raman bands are observed at 2288, 2438, 2814, 3152, 3314, 3448 and 3521 cm-1. Two Raman bands at 2288 and 2438 cm-1 are ascribed to very strongly hydrogen bonded water. The broader Raman bands at 3152 and 3314 cm-1 may be assigned to adsorbed water and not so strongly hydrogen bonded water in the molecular structure of geminate. Two bands at 3448 and 3521 cm-1 are assigned to the OH stretching vibrations of the (AsO3OH)2- units. Raman spectroscopy identified Raman bands attributable to AsO43- and AsO3OH2- units.

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Thomas Young (1773-1829) carried out major pioneering work in many different subjects. In 1800 he gave the Bakerian Lecture of the Royal Society on the topic of the “mechanism of the eye”: this was published in the following year (Young, 1801). Young used his own design of optometer to measure refraction and accommodation, and discovered his own astigmatism. He considered the different possible origins of accommodation and confirmed that it was due to change in shape of the lens rather than to change in shape of the cornea or an increase in axial length. However, the paper also dealt with many other aspects of visual and ophthalmic optics, such as biometric parameters, peripheral refraction, longitudinal chromatic aberration, depth-of-focus and instrument myopia. These aspects of the paper have previously received little attention. We now give detailed consideration to these and other less-familiar features of Young’s work and conclude that his studies remain relevant to many of the topics which currently engage visual scientists.

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about 82 million immigrants in the OECD area; and worldwide, there are about 191 million immigrants and displaced persons, and some 30-40 million unauthorised immigrants. Also according to recent OECD report, little in-depth research has been carried out to-date to help decision makers in government, business, and society at large, to better understand the complexities and wider consequences of future migration flows. Literatures have also indicated that the lack of a skilled population in muchneeded occupations in countries of destination have contributed to the need to bring in skilled foreign workers. Furthermore, despite current global financial crisis, some areas of occupation are in need of skilled workers such that in a job-scarce environment jobs become fewer and employers are more likely to demand skilled workers from both natives and immigrants. Global competition for labour is expected to intensify, especially for top talent, highly qualified and semi-skilled individuals. This exacerbate the problems faced by current skilled immigrants and skilled refugees, particularly those from non-main English speaking countries who are not employed at optimal skill level in countries of destination. The research study investigates whether skilled immigrants are being effectively utilised in their countries of destination, in the context of employment. In addition to skilled immigrants, data sampling will also include skilled refugees who, although arriving under the humanitarian program, possess formal qualifications from their country of origin. Underlying variables will be explored such as the strength of social capital or interpersonal ties; and human capital in terms of educational attainment and proficiency in the English Language. The aim of the study is to explain the relationship between the variables; and whether the variables influence the employment outcomes. A broad-ranging preliminary literature review has been undertaken to explore the substantial bodies of knowledge on skilled immigrants worldwide, including skilled refugees; and to investigate whether the utilisation issues are universal or specific to a country. In addition, preliminary empirical research and analysis has been undertaken, to set the research focus and to identify the problems beyond literature. Preliminary findings have indicated that immigrants and refugees from non-main English speaking countries are particularly impacted by employment issues regardless of their skills and qualifications acquired in their country of origins; compared with immigrants from main-English speaking countries. Preliminary findings from the literature review also indicate that gaps in knowledge still exist. Although the past two decades have witnessed a virtual explosion of theory and research on international migration, no in-depth research has been located that specifically links immigrants and refugees social and human capitals in terms of employment outcomes. This research study aims to fill these gaps in research; and subsequently contribute to contemporary body of knowledge in literatures on the utilisation of skilled immigrants and skilled refugees, specifically those from non-main English speaking countries. A mixed methods design will be used, which incorporates techniques from both quantitative and qualitative research traditions that will be triangulated at the end of the data collection stage.

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Like other nations, Australia has experienced significant change in the past few decades as its society has become increasingly diverse. The new cultures and traditions that result from ethnic and religious diversity have both enriched Australian society and presented it with some challenges. Other challenges have resulted from increased globalisation. For example, the economic fallout from the recent global financial crisis indicates that global issues can impact across a range of levels, from multinational corporations and nation-states to local sites and individual livelihoods. Some suggest that Australia fared better than other nations during this economic crisis because of its export trade with China. Although this is disputed by economists, it highlights another facet of change that is impacting on Australian society and this relates to Australia’s growing engagement with the nations of Asia. There is increasing awareness in education systems that if young people are to achieve their potential as future citizens they need to be able to negotiate the cultural, social, political and economic ties that connect them to the global and regional community through work, leisure and citizenship. Multicultural education, global studies and studies of Asia play a particular part in helping young people to: • appreciate cultural diversity within and beyond their own nation • imagine with some accuracy how others view their world • participate in shaping a better future. This chapter explores the origins, distinctions and common features of each approach.

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We argue that the sustained successful operation of an ES is determined by, and is dependent on, multiple organizational stakeholders. The single greatest organizational barrier to EIS success and achieving widespread organizational benefits can be attributed to the way in which different subcultures treat data critical to EIS operation. Building on Lee & Strong’s (2004) data roles we incorporate Schien’s (1996) cultural framework along with DeLone and McLean’s (2003) dimensions of IS success, unpacking the underlying drivers of behaviors as they relate to EIS data. Further, we explain the origins of data based conflict resulting in poor EIS data utilization.

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There is increasing epidemiological and molecular evidence that cutaneous melanomas arise through multiple causal pathways. The purpose of this study was to explore the relationship between germline and somatic mutations in a population-based series of melanoma patients to reshape and refine the divergent pathway model for melanoma. Melanomas collected from 123 Australian patients were analyzed for melanocortin-1 receptor (MC1R) variants and mutations in the BRAF and NRAS genes. Detailed phenotypic and sun exposure data were systematically collected from all patients. We found that BRAF-mutant melanomas were significantly more likely from younger patients and those with high nevus counts, and were more likely in melanomas with adjacent neval remnants. Conversely, BRAF-mutant melanomas were significantly less likely in people with high levels of lifetime sun exposure. We observed no association between germline MC1R status and somatic BRAF mutations in melanomas from this population. BRAF-mutant melanomas have different origins from other cutaneous melanomas. These data support the divergent pathways hypothesis for melanoma, which may require a reappraisal of targeted cancer prevention activities.

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The mineral dussertite, a hydroxy-arsenate mineral of formula BaFe3+3(AsO4)2(OH)5, has been studied by Raman complimented with infrared spectroscopy. The spectra of three minerals from different origins were investigated and proved quite similar, although some minor differences were observed. In the Raman spectra of Czech dussertite, four bands are observed in the 800 to 950 cm-1 region. The bands are assigned as follows: the band at 902 cm-1 is assigned to the (AsO4)3- ν3 antisymmetric stretching mode, at 870 cm-1 to the (AsO4)3- ν1 symmetric stretching mode, and both at 859 cm-1 and 825 cm-1 to the As-OM2+/3+ stretching modes/and or hydroxyls bending modes. Raman bands at 372 and 409 cm-1 are attributed to the ν2 (AsO4)3- bending mode and the two bands at 429 and 474 cm-1 are assigned to the ν4 (AsO4)3- bending mode. An intense band at 3446 cm-1 in the infrared spectrum and a complex set of bands centred upon 3453 cm-1 in the Raman spectrum are attributed to the stretching vibrations of the hydrogen bonded (OH)- units and/or water units in the mineral structure. The broad infrared band at 3223 cm-1 is assigned to the vibrations of hydrogen bonded water molecules. Raman spectroscopy identified Raman bands attributable to (AsO4)3- and (AsO3OH)2- units.

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The importance of the first year experience (FYE) to success at university is well documented and supported with the transition into university regarded as crucial. While there is also support for the notion that a successful FYE should have a whole-of-institution focus and models have been proposed, many institutions still face challenges in achieving institution-wide FYE program implementation. This paper discusses the origins, theoretical and empirical bases and structure of an institution-wide approach to the FYE. It uses a case study of the Transitions In Project (TIP) at the Queensland University of Technology to illustrate how institution-wide FYE program implementation can be achieved and sustained. TIP had four inter-related projects focussing on at-risk students, first year curriculum, learning resources and staff development. The key aim of TIP was to identify good practice and institutionalise it in a sustainable way. The degree of success in achieving this is evaluated.

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Restrictions to effective dispersal and gene flow caused by the fragmentation of ancient supercontinents are considered to have driven diversification and speciation on disjunct landmasses globally. Investigating the role that these processes have played in the development of diversity within and among taxa is crucial to understanding the origins and evolution of regional biotas. Within the chironomid (non-biting midge) subfamily Orthocladiinae (Diptera: Chironomidae), a group of genera that are distributed across the austral continents (Australia, New Zealand, South America) have been proposed to represent a relict Gondwanan clade. We used a molecular approach to resolve relationships among taxa with the aim to determine the relative roles that vicariance and dispersal may have played in the evolution of this group. Continental biotas did not form monophyletic groups, in accordance with expectations given existing morphological evidence. Patterns of phylogenetic relationships among taxa did not accord with expected patterns based on the geological sequence of break-up of the Gondwanan supercontinent. Likewise, divergence time estimates, particularly for New Zealand taxa, largely post-dated continental fragmentation and implied instead that several transoceanic dispersal events may have occurred post-vicariance. Passive dispersal of gravid female chironomid adults is the most likely mechanism for transoceanic movement, potentially facilitated by West Wind Drift or anti-cyclone fronts. Estimated timings of divergence among Australian and South American Botryocladius, on the other hand, were congruent with the proposed ages of separation of the two continents from Antarctica. Taken together, these data suggest that a complex relationship between both vicariance and dispersal may explain the evolution of this group. The sampling regime we implemented here was the most intensive yet performed for austral members of the Orthocladiinae and unsurprisingly revealed several novel taxa that will require formal description.

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Climate change is an urgent global public health issue with substantial predicted impacts in the coming decades. Concurrently, global burden of disease studies highlight problems such as obesity, mental health problems and a range of other chronic diseases, many of which have origins in childhood. There is a unique opportunity to engage children in both health promotion and education for sustainability during their school years to help ameliorate both environmental and health issues. Evidence exists for the most effective ways to do this, through education that is empowering, action orientated and relevant to children’s day to day interests and concerns, and by tailoring such education to different educational sectors. The aim of this chapter is to argue the case for sustainability education in schools that links with health promotion and that adopts a practical approach to engaging children in these important public health and environmental issues. We describe two internationally implemented whole-school reform movements, Health Promoting Schools (HPS) and Sustainable Schools (SS) which seek to operationalise transformative educational processes. Drawing on international evidence and Australian case examples, we contend that children’s active involvement in such processes is not only educationally engaging and rewarding, it also contributes to human and environmental resilience and health. Further, school settings can play an important ecological public health role, incubating and amplifying the socially transformative changes urgently required to create pathways to healthy, just and sustainable human futures, on a viable planet.

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This paper examines the effects and origins of balanced skills among nascent entrepreneurs. In a first step we extend Lazear’s jack-of-all-trades theory to formally model performance effects of balanced skills. In a second step we investigate potential sources of balanced skills related to the investment hypothesis and the endowment hypothesis. Analyzing data on 100 high-potential nascent projects, we find support for the hypothesis that balanced skills are an important factor for making progress in the venture creation process. Interestingly, none of the traditional human capital indicators such as prior managerial and entrepreneurial experience predict the progress of the project. However, they contribute to a balanced skill set, supporting the investment hypothesis on balanced skill origins. We also find empirical evidence for the endowment hypothesis suggesting that a balanced skill set is deeply rooted in the adolescent development and personality characteristics of the nascent entrepreneurs.

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This paper demonstrates the capabilities of wavelet transform (WT) for analyzing important features related to bottleneck activations and traffic oscillations in congested traffic in a systematic manner. In particular, the analysis of loop detector data from a freeway shows that the use of wavelet-based energy can effectively identify the location of an active bottleneck, the arrival time of the resulting queue at each upstream sensor location, and the start and end of a transition during the onset of a queue. Vehicle trajectories were also analyzed using WT and our analysis shows that the wavelet-based energies of individual vehicles can effectively detect the origins of deceleration waves and shed light on possible triggers (e.g., lane-changing). The spatiotemporal propagations of oscillations identified by tracing wavelet-based energy peaks from vehicle to vehicle enable analysis of oscillation amplitude, duration and intensity.

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In this paper we identify the origins of stop-and-go (or slow-and-go) driving and measure microscopic features of their propagations by analyzing vehicle trajectories via Wavelet Transform. Based on 53 oscillation cases analyzed, we find that oscillations can be originated by either lane-changing maneuvers (LCMs) or car-following behavior (CF). LCMs were predominantly responsible for oscillation formations in the absence of considerable horizontal or vertical curves, whereas oscillations formed spontaneously near roadside work on an uphill segment. Regardless of the trigger, the features of oscillation propagations were similar in terms of propagation speed, oscillation duration, and amplitude. All observed cases initially exhibited a precursor phase, in which slow-and-go motions were localized. Some of them eventually transitioned into a well developed phase, in which oscillations propagated upstream in queue. LCMs were primarily responsible for the transition, although some transitions occurred without LCMs. Our findings also suggest that an oscillation has a regressive effect on car following behavior: a deceleration wave of an oscillation affects a timid driver (with larger response time and minimum spacing) to become less timid and an aggressive driver less aggressive, although this change may be short-lived. An extended framework of Newell’s CF is able to describe the regressive effects with two additional parameters with reasonable accuracy, as verified using vehicle trajectory data.

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Traffic oscillations are typical features of congested traffic flow that are characterized by recurring decelerations followed by accelerations. However, people have limited knowledge on this complex topic. In this research, 1) the impact of traffic oscillations on freeway crash occurrences has been measured using the matched case-control design. The results consistently reveal that oscillations have a more significant impact on freeway safety than the average traffic states. 2) Wavelet Transform has been adopted to locate oscillations' origins and measure their characteristics along their propagation paths using vehicle trajectory data. 3) Lane changing maneuver's impact on the immediate follower is measured and modeled. The knowledge and the new models generated from this study could provide better understanding on fundamentals of congested traffic; enable improvements to existing traffic control strategies and freeway crash countermeasures; and instigate people to develop new operational strategies with the objective of reducing the negative effects of oscillatory driving.

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This volume breaks new ground by approaching Socially Responsible Investment (SRI) as an explicitly ethical practice in financial markets. The work explains the philosophical and practical shortcomings of ‘long term shareholder value’ and the origins and conceptual structure of SRI, and links its pursuit to both its deeper philosophical foundations and the broader, multi-dimensional global movement towards greater social responsibility in global markets. Interviews with fund managers in the Australian SRI sector generate recommendations for better integrating ethics into SRI practice via ethically informed engagement with invested companies, and an in-depth discussion of the central practical SRI issue of fiduciary responsibility strengthens the case in favour of SRI. The practical and ethical theoretical perspectives are then brought together to sketch out an achievable ideal for SRI worldwide, in which those who are involved in investment and business decisions become part of an ‘ethical chain’ of decision makers linking the ultimate owners of capital with the business executives who frame, advocate and implement business strategies. In between there are investment advisors, fund managers, business analysts and boards. The problem lies in the fact that the ultimate owners are discouraged from considering their own values, or even their own long term interests, whilst the others often look only to short term interests. The solution lies in the latter recognising themselves as links in the ethical chain.