960 resultados para Modern Age


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After attending this presentation, attendees will gain awareness of: (1) the error and uncertainty associated with the application of the Suchey-Brooks (S-B) method of age estimation of the pubic symphysis to a contemporary Australian population; (2) the implications of sexual dimorphism and bilateral asymmetry of the pubic symphysis through preliminary geometric morphometric assessment; and (3) the value of three-dimensional (3D) autopsy data acquisition for creating forensic anthropological standards. This presentation will impact the forensic science community by demonstrating that, in the absence of demographically sound skeletal collections, post-mortem autopsy data provides an exciting platform for the construction of large contemporary ‘virtual osteological libraries’ for which forensic anthropological research can be conducted on Australian individuals. More specifically, this study assesses the applicability and accuracy of the S-B method to a contemporary adult population in Queensland, Australia, and using a geometric morphometric approach, provides an insight to the age-related degeneration of the pubic symphysis. Despite the prominent use of the Suchey-Brooks (1990) method of age estimation in forensic anthropological practice, it is subject to intrinsic limitations, with reports of differential inter-population error rates between geographical locations1-4. Australian forensic anthropology is constrained by a paucity of population specific standards due to a lack of repositories of documented skeletons. Consequently, in Australian casework proceedings, standards constructed from predominately American reference samples are applied to establish a biological profile. In the global era of terrorism and natural disasters, more specific population standards are required to improve the efficiency of medico-legal death investigation in Queensland. The sample comprises multi-slice computed tomography (MSCT) scans of the pubic symphysis (slice thickness: 0.5mm, overlap: 0.1mm) on 195 individuals of caucasian ethnicity aged 15-70 years. Volume rendering reconstruction of the symphyseal surface was conducted in Amira® (v.4.1) and quantitative analyses in Rapidform® XOS. The sample was divided into ten-year age sub-sets (eg. 15-24) with a final sub-set of 65-70 years. Error with respect to the method’s assigned means were analysed on the basis of bias (directionality of error), inaccuracy (magnitude of error) and percentage correct classification of left and right symphyseal surfaces. Morphometric variables including surface area, circumference, maximum height and width of the symphyseal surface and micro-architectural assessment of cortical and trabecular bone composition were quantified using novel automated engineering software capabilities. The results of this study demonstrated correct age classification utilizing the mean and standard deviations of each phase of the S-B method of 80.02% and 86.18% in Australian males and females, respectively. Application of the S-B method resulted in positive biases and mean inaccuracies of 7.24 (±6.56) years for individuals less than 55 years of age, compared to negative biases and mean inaccuracies of 5.89 (±3.90) years for individuals greater than 55 years of age. Statistically significant differences between chronological and S-B mean age were demonstrated in 83.33% and 50% of the six age subsets in males and females, respectively. Asymmetry of the pubic symphysis was a frequent phenomenon with 53.33% of the Queensland population exhibiting statistically significant (χ2 - p<0.01) differential phase classification of left and right surfaces of the same individual. Directionality was found in bilateral asymmetry, with the right symphyseal faces being slightly older on average and providing more accurate estimates using the S-B method5. Morphometric analysis verified these findings, with the left surface exhibiting significantly greater circumference and surface area than the right (p<0.05). Morphometric analysis demonstrated an increase in maximum height and width of the surface with age, with most significant changes (p<0.05) occurring between the 25-34 and 55-64 year age subsets. These differences may be attributed to hormonal components linked to menopause in females and a reduction in testosterone in males. Micro-architectural analysis demonstrated degradation of cortical composition with age, with differential bone resorption between the medial, ventral and dorsal surfaces of the pubic symphysis. This study recommends that the S-B method be applied with caution in medico-legal death investigations of unknown skeletal remains in Queensland. Age estimation will always be accompanied by error; therefore this study demonstrates the potential for quantitative morphometric modelling of age related changes of the pubic symphysis as a tool for methodological refinement, providing a rigor and robust assessment to remove the subjectivity associated with current pelvic aging methods.

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Current forensic practice in age estimation relies on the application of morphological standards as a means to characterize complex threedimensional skeletal surfaces. Research in our laboratory has demonstrated that the application of the morphologically based Suchey-Brooks method to a contemporary Queensland, Australian population demonstrated significant inaccuracy in age-estimation. Consequently, this study presents preliminary results to quantify age-related skeletal changes of the pubic symphysis in Queensland individuals using novel geometric and micro-architectural protocols that have the potential of improving age estimation in the forensic context. Computed tomography scans of the right and left pubis were obtained from Caucasian individuals aged 15–70 years (n=195) from the Queensland Health Forensic and Scientific Services. Morphometric variables including surface area, circumference, maximum height and width of the symphyseal surface, and micro-architectural assessment of cortical and trabecular bone structure were conducted in Rapidform XOS and Osteomeasure, respectively. Morphometric analysis demonstrated increases in maximum height and width of the surface with age independent of gender, with most significant (P<0.05) changes between the 25–34 and 55–64 year subsets. Sexual dimorphism and bilateral asymmetry were prominent features in the Queensland population. Micro-architectural analysis demonstrated degradation of cortical composition with age, with differential bone resorption between the medial, ventral and dorsal aspects of the symphysis. The ability to quantitatively model age-related changes to the pubic symphysis provides potential for future methodological refinement, where rigor and robust geometric assessment of the surface may remove the subjectivity associated with aging the pubic symphysis.

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This thesis examines the role of government as proprietor, preserver and user of copyright material under the Copyright Act 1968 (Cth) and the policy considerations which Australian law should take into account in that role. There are two recurring themes arising in this examination which are significant to the recommendations and conclusions. The first is whether the needs and status of government should be different from private sector institutions, which also obtain copyright protection under the law. This theme stems from the 2005 Report on Crown Copyright by the Copyright Law Review Committee and the earlier Ergas Committee Report which are discussed in Chapters 2 and 8 of this thesis. The second is to identify the relationship between government copyright law and policy, national cultural policy and fundamental governance values. This theme goes to the essence of the thesis. For example, does the law and practice of government copyright properly reflect technological change in the way we now access and use information and does it facilitate the modern information management principles of government? Is the law and practice of government copyright consistent with the greater openness and accountability of government? The thesis concludes that government copyright law and practice in each of the three governmental roles recognised under the Copyright Act 1968 has not responded adequately to the information age and to the desire and the ability of individuals to access information quickly and effectively. The solution offered in this thesis is reform of the law and of public policy that is in step with access to information policy, the promotion of better communication and interaction with the community, and the enhanced preservation of government and private copyright materials for reasons of government accountability, effective administration and national culture and heritage.

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We investigated critical belief-based targets for promoting the introduction of solid foods to infants at six months. First-time mothers (N = 375) completed a Theory of Planned Behaviour belief-based questionnaire and follow-up questionnaire assessing the age the infant was first introduced to solids. Normative beliefs about partner/spouse (β = 0.16) and doctor (β = 0.22), and control beliefs about commercial baby foods available for infants before six months (β = −0.20), predicted introduction of solids at six months. Intervention programs should target these critical beliefs to promote mothers’ adherence to current infant feeding guidelines to introduce solids at around six months.

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The Australian Government’s current workforce reforms in early childhood education and care (ECEC) include a major shift in qualification requirements. The new requirement is that university four-year degree-qualified teachers are employed in before-school contexts, including child care. Ironically, recent research studies show that, in Australia, the very preservice teachers who are enrolled in these degree programs have a reluctance to work in childcare. This article reports on part of a larger study which is inquiring into how early childhood teacher professional identities are discursively produced, and provides a partial mapping of the literature. One preservice teacher’s comment provides the starting point, and the paper locates some the discourses that are accessible to preservice teachers as they prepare for the early years workforce. An awareness of the discursive field provides a sound background for preparing early childhood teachers. A challenge for the field is to consider which discourses are dominant, and how they potentially work to privilege work in some ECEC contexts over others.

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Selenium (Se) is an essential trace element and the clinical consequences of Se deficiency have been well-documented. Se is primarily obtained through the diet and recent studies have suggested that the level of Se in Australian foods is declining. Currently there is limited data on the Se status of the Australian population so the aim of this study was to determine the plasma concentration of Se and glutathione peroxidase (GSH-Px), a well-established biomarker of Se status. Furthermore, the effect of gender, age and presence of cardiovascular disease (CVD) was also examined. Blood plasma samples from healthy subjects (140 samples, mean age = 54 years; range, 20-86 years) and CVD patients (112 samples, mean age = 67 years; range, 40-87 years) were analysed for Se concentration and GSH-Px activity. The results revealed that the healthy Australian cohort had a mean plasma Se level of 100.2 +/- 1.3 microg Se/L and a mean GSH-Px activity of 108.8 +/- 1.7 U/L. Although the mean value for plasma Se reached the level required for optimal GSH-Px activity (i.e. 100 microg Se/L), 47% of the healthy individuals tested fell below this level. Further evaluation revealed that certain age groups were more at risk of a lowered Se status, in particular, the oldest age group of over 81 years (females = 97.6 +/- 6.1 microg Se/L; males = 89.4 +/- 3.8 microg Se/L). The difference in Se status between males and females was not found to be significant. The presence of CVD did not appear to influence Se status, with the exception of the over 81 age group, which showed a trend for a further decline in Se status with disease (plasma Se, 93.5 +/- 3.6 microg Se/L for healthy versus 88.2 +/- 5.3 microg Se/L for CVD; plasma GSH-Px, 98.3 +/- 3.9 U/L for healthy versus 87.0 +/- 6.5 U/L for CVD). These findings emphasise the importance of an adequate dietary intake of Se for the maintenance of a healthy ageing population, especially in terms of cardiovascular health.

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Adenosine is an important cardioprotective agent that works via several adenosine receptor (ADOR) subtypes to regulate cardiovascular activity. It is well established that functional responses to adenosine decline with age. What is unclear, though, is whether these changes occur at the receptor, second messenger or translational level. In this study we determined the effect of age on cardiac adenosine receptor expression using the housekeeping gene 18S rRNA versus the adenosine A2B receptor gene as internal controls. Absolute quantification showed that no age-related changes occurred in the expression of 18S rRNA or adenosine A2B receptor internal control genes. Subsequently, relative analysis of the adenosine receptor subtypes using 18S rRNA found a significant age-related reduction in the expression of the adenosine A1 receptor (5.5-fold), with no changes in the expression of the adenosine A2A, A2B and A3 receptors. When using the expression of the adenosine A2B receptor as the internal control gene, a significant down regulation of both the adenosine A1 (5.4-fold) and A2A (2.2-fold) receptors with no change in the expression of adenosine A3 receptor was found. Therefore, the high level of expression of the 18S rRNA housekeeping gene was found to mask a significant change in expression of the adenosine A2A receptor with age. Ultimately, these findings show an age-related reduction in adenosine A1 and A2A receptor expression in rat heart.

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In line with repeated recent calls for research on specific forms of growth rather than on an undifferentiated notion of “total growth,” our study contributes to the understanding of entrepreneurial growth. By this we mean growth through expansion into new geographic markets and/or via the introduction of new products or services. Building on Penrose's theory of the growth of the firm and on the research streams she has in part inspired, we investigate the impact of knowledge acquisition from international markets on entrepreneurial growth both at home and abroad. We further suggest that the effects of international knowledge acquisition on entrepreneurial growth will vary with firm age. Utilizing longitudinal data on 138 small and medium-sized enterprises (SMEs), we find that the acquisition of knowledge from international markets fuels growth through market development, and that this effect is stronger for international expansion than domestic expansion. Our results also show that firm age negatively moderates the relationship between international knowledge acquisition and entrepreneurial growth via the introduction of new products or services. Specifically, international knowledge acquisition has a positive effect on growth via new products/services development in young firms, but a negative effect in mature firms. We assume this reflects changes over time in how international knowledge is managed.

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Literacy Theories for the Digital Age insightfully brings together six essential approaches to literacy research and educational practice. The book provides powerful and accessible theories for readers, including Socio-cultural, Critical, Multimodal, Socio-spatial, Socio-material and Sensory Literacies. The brand new Sensory Literacies approach is an original and visionary contribution to the field, coupled with a provocative foreword from leading sensory anthropologist David Howes. This dynamic collection explores a legacy of literacy research while showing the relationships between each paradigm, highlighting their complementarity and distinctions. This highly relevant compendium will inspire readers to explore new frontiers of thought and practice in times of diversity and technological change.

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High-precision analysis using accelerator mass spectrometry (AMS) was performed upon known-age Holocene and modern, pre-bomb coral samples to generate a marine reservoir age correction value (ΔR) for the Houtman-Abrolhos Archipelago (28.7°S, 113.8°E) off the Western Australian coast. The mean ΔR value calculated for the Abrolhos Islands, 54 ± 30 yr (1σ) agrees well with regional ΔR values for Leeuwin Current source waters (N-NW Australia-Java) of 60 ± 38. The Abrolhos Islands show little variation with ΔR values of the northwestern and north Australian coast, underlining the dominance of the more equilibrated western Pacific-derived waters of the Leeuwin Current over local upwelling. The Abrolhos Islands ΔR values have remained stable over the last 2896 yr cal BP, being also attributed to the Leeuwin Current and the El Niño Southern Oscillation (ENSO) signal during this period. Expected future trends will be a strengthening of the teleconnection of the Abrolhos Islands to the climatic patterns of the equatorial Pacific via enhanced ENSO and global warming activity strengthening the Leeuwin Current. The possible effect upon the trend of future ΔR values may be to maintain similar values and an increase in stability. However, warming trends of global climate change may cause increasing dissimilarity of ΔR values due to the effects of increasing heat stress upon lower-latitude coral communities.

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Background Several lines of evidence suggests that transcription factors are involved in the pathogenesis of Multiple Sclerosis (MS) but a complete mapping the whole network has been elusive. One of the reasons is that there are several clinical subtypes of MS and transcription factors which may be involved in one subtype may not be in others. We investigated the possibility that this network could be mapped using microarray technologies and modern bioinformatics methods on a dataset from whole blood in 99 untreated MS patients (36 Relapse Remitting MS, 43 Primary Progressive MS, and 20 Secondary Progressive MS) and 45 age-matched healthy controls, Methodology/Principal Findings We have used two different analytical methodologies: a differential expression analysis and a differential co-expression analysis, which have converged on a significant number of regulatory motifs that seem to be statistically overrepresented in genes which are either differentially expressed (or differentially co-expressed) in cases and controls (e.g. V$KROX_Q6, p-value < 3.31E-6; V$CREBP1_Q2, p-value < 9.93E-6, V$YY1_02, p-value < 1.65E-5). Conclusions/significance: Our analysis uncovered a network of transcription factors that potentially dysregulate several genes in MS or one or more of its disease subtypes. Analysing the published literature we have found that these transcription factors are involved in the early T-lymphocyte specification and commitment as well as in oligodendrocytes dedifferentiation and development. The most significant transcription factors motifs were for the Early Growth response EGR/KROX family, ATF2, YY1 (Yin and Yang 1), E2F-1/DP-1 and E2F-4/DP-2 heterodimers, SOX5, and CREB and ATF families.

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The inconsistent findings of past board diversity research demand a test of competing linear and curvilinear diversity–performance predictions. This research focuses on board age and gender diversity, and presents a positive linear prediction based on resource dependence theory, a negative linear prediction based on social identity theory, and an inverted U-shaped curvilinear prediction based on the integration of resource dependence theory with social identity theory. The predictions were tested using archival data on 288 large organizations listed on the Australian Securities Exchange, with a 1-year time lag between diversity (age and gender) and performance (employee productivity and return on assets). The results indicate a positive linear relationship between gender diversity and employee productivity, a negative linear relationship between age diversity and return on assets, and an inverted U-shaped curvilinear relationship between age diversity and return on assets. The findings provide additional evidence on the business case for board gender diversity and refine the business case for board age diversity.

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The arena of intellectual property encompasses streams that often interrelate and overlap in protecting different aspects of intellectual property. Australian commentators suggest that ‘one of the most troublesome areas in the entire field of intellectual property has been the relationship between copyright protection for artistic works under the Copyright Act 1968 (Cth) and protection for registered designs under the Designs Act 1906 (Cth).’ [McKeough, J., Stewart, A., & Griffith, P. (2004). Intellectual property in Australia (3rd ed.). Chatswood, NSW: Butterworths.] [Ricketson, S., Richardson, M., & Davison, M. (2009). Intellectual property: Cases, materials and commentary (4th ed.). Chatswood, NSW: LexisNexis Butterworths.] This overlap has caused much confusion for both creators of artistic works and industrial designs, as there is an uncertainty of whether protection against infringement is afforded under the Copyright Act 1988 (Cth) or whether the Designs Act 2003 (Cth) will apply. In Australia, there is limited precedent that examines the crossover between copyright and designs. Essentially, the cases that have tested this issue remain unclear as to whether a design applied industrially will invoke copyright protection. The cases demonstrate that there is an inconsistency in this area despite the aims of the new provisions of the Designs Act 2003 (Cth) to close the loopholes between copyright and designs. This paper will discuss and evaluate the relationship between copyright protection for artistic works and protection for registered designs with respect to the Designs Act 2003 (Cth).

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The formalin test is increasingly applied as a model of inflammatory pain using high formalin concentrations (5–15%). However, little is known about the effects of low formalin concentrations on related behavioural responses. To examine this, rat pups were subjected to various concentrations of formalin at four developmental stages: 7, 13, 22, and 82 days of age. At postnatal day (PND) 7, sex differences in flinching but not licking responses were observed with 0.5% formalin evoking higher flinching in males than in females. A dose response was evident in that 0.5% formalin also produced higher licking responses compared to 0.3% or 0.4% formalin. At PND 13, a concentration of 0.8% formalin evoked a biphasic response. At PND 22, a concentration of 1.1% evoked higher flinching and licking responses during the late phase (10–30 min) in both males and females. During the early phase (0–5 min), 1.1% evoked higher licking responses compared to 0.9% or 1% formalin. 1.1% formalin produced a biphasic response that was not evident with 0.9 or 1%. At PND 82, rats displayed a biphasic pattern in response to three formalin concentrations (1.25%, 1.75% and 2.25%) with the presence of an interphase for both 1.75% and 2.25% but not for 1.25%. These data suggest that low formalin concentrations induce fine-tuned responses that are not apparent with the high formalin concentration commonly used in the formalin test. These data also show that the developing nociceptive system is very sensitive to subtle changes in formalin concentrations.

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Several fringing coral reefs in Moreton Bay, Southeast Queensland, some 300 km south of the Great Barrier Reef (GBR), are set in a relatively high latitude, estuarine environment that is considered marginal for coral growth. Previous work indicated that these marginal reefs, as with many fringing reefs of the inner GBR, ceased accreting in the mid-Holocene. This research presents for the first time data from the subsurface profile of the mid-Holocene fossil reef at Wellington Point comprising U/Th dates of in situ and framework corals, and trace element analysis from the age constrained carbonate fragments. Based on trace element proxies the palaeo-water quality during reef accretion was reconstructed. Results demonstrate that the reef initiated more than 7,000 yr BP during the post glacial transgression, and the initiation progressed to the west as sea level rose. In situ micro-atolls indicate that sea level was at least 1 m above present mean sea level by 6,680 years ago. The reef remained in "catch-up" mode, with a seaward sloping upper surface, until it stopped aggrading abruptly at ca 6,000 yr BP; no lateral progradation occurred. Changes in sediment composition encountered in the cores suggest that after the laterite substrate was covered by the reef, most of the sediment was produced by the carbonate factory with minimal terrigenous influence. Rare earth element, Y and Ba proxies indicate that water quality during reef accretion was similar to oceanic waters, considered suitable for coral growth. A slight decline in water quality on the basis of increased Ba in the later stages of growth may be related to increased riverine input and partial closing up of the bay due to either tidal delta progradation, climatic change and/or slight sea level fall. The age data suggest that termination of reef growth coincided with a slight lowering of sea level, activation of ENSO and consequent increase in seasonality, lowering of temperatures and the constrictions to oceanic flushing. At the cessation of reef accretion the environmental conditions in the western Moreton Bay were changing from open marine to estuarine. The living coral community appears to be similar to the fossil community, but without the branching Acropora spp. that were more common in the fossil reef. In this marginal setting coral growth periods do not always correspond to periods of reef accretion due to insufficient coral abundance. Due to several environmental constraints modern coral growth is insufficient for reef growth. Based on these findings Moreton Bay may be unsuitable as a long term coral refuge for most species currently living in the GBR.