995 resultados para 312


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Background Migraine is a brain disorder affecting ∼12% of the Caucasian population. Genes involved in neurological, vascular, and hormonal pathways have all been implicated in predisposing individuals to developing migraine. The migraineur presents with disabling head pain and varying symptoms of nausea, emesis, photophobia, phonophobia, and occasionally visual sensory disturbances. Biochemical and genetic studies have demonstrated dysfunction of neurotransmitters: serotonin, dopamine, and glutamate in migraine susceptibility. Glutamate mediates the transmission of excitatory signals in the mammalian central nervous system that affect normal brain function including cognition, memory and learning. The aim of this study was to investigate polymorphisms in the GRIA2 and GRIA4 genes, which encode subunits of the ionotropic AMPA receptor for association in an Australian Caucasian population. Methods Genotypes for each polymorphism were determined using high resolution melt analysis and the RFLP method. Results Statistical analysis showed no association between migraine and the GRIA2 and GRIA4 polymorphisms investigated. Conclusions Although the results of this study showed no significant association between the tested GRIA gene variants and migraine in our Australian Caucasian population further investigation of other components of the glutamatergic system may help to elucidate if there is a relationship between glutamatergic dysfunction and migraine.

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Objectives: To examine factors associated with the uptake of i) long-acting reversible, ii) permanent and iii) traditional contraceptive methods among Australian women. Methods: Participants in the Australian Longitudinal Study on Women's Health born in 1973–78 reported on their contraceptive use at three surveys: 2003, 2006 and 2009. The participants were 5,849 women aged 25–30 in 2003 randomly sampled from Medicare. The main outcome measure was current contraceptive method at age 28–33 years categorised as long-acting reversible methods (implant, IUD, injection), permanent (tubal ligation, vasectomy), and traditional methods (oral contraceptive pills, condoms, withdrawal, safe period). Results: Compared to women living in major cities, women in inner regional areas were more likely to use long-acting (OR=1.26, 95%CI 1.03–1.55) or permanent methods (OR=1.43, 95%CI 1.17–1.76). Women living in outer regional/remote areas were more likely than women living in cities to use long-acting (OR=1.65, 95%CI 1.31–2.08) or permanent methods (OR=1.69, 95%CI 1.43–2.14). Conclusions: Location of residence is an important factor in women's choices about long-acting and permanent contraception in addition to the number and age of their children. Implications: Further research is needed to understand the role of geographical location in women's access to contraceptive options in Australia.

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Jackson (2005) developed a hybrid model of personality and learning, known as the learning styles profiler (LSP) which was designed to span biological, socio-cognitive, and experiential research foci of personality and learning research. The hybrid model argues that functional and dysfunctional learning outcomes can be best understood in terms of how cognitions and experiences control, discipline, and re-express the biologically based scale of sensation-seeking. In two studies with part-time workers undertaking tertiary education (N equals 137 and 58), established models of approach and avoidance from each of the three different research foci were compared with Jackson's hybrid model in their predictiveness of leadership, work, and university outcomes using self-report and supervisor ratings. Results showed that the hybrid model was generally optimal and, as hypothesized, that goal orientation was a mediator of sensation-seeking on outcomes (work performance, university performance, leader behaviours, and counterproductive work behaviour). Our studies suggest that the hybrid model has considerable promise as a predictor of work and educational outcomes as well as dysfunctional outcomes.

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This paper investigates the outsourcing of income tax return preparation by Australian accounting firms. It identifies the extent to which firms are currently outsourcing accounting services or considering outsourcing accounting services, with a focus on personal and business income tax return preparation. The motivations and barriers for outsourcing by Australian accounting firms are also considered in this paper. Privacy, security of client data, and the competence of the outsourcing provider's staff have been identified as risks associated with outsourcing. An expectation relating to confidentiality of client data is also examined in this paper. Statistical analysis of data collected from a random sample of Australian accounting firms using a survey questionnaire provided the empirical data for the paper. The results indicate that the majority of Australian accounting firms are either currently outsourcing or considering outsourcing accounting services, and firms are outsourcing taxation preparation both onshore and offshore. The results also indicate that firms expect the volume of outsourced work to increase in the future. In contrast to the literature identifying labour arbitrage as the primary driver for organisations choosing to outsource, this study found that the main factors considered by accounting firms in the decision to outsource were to expedite delivery of services to clients and to enable the firm to focus on core competencies. Data from this study also supports the literature which ndicates that not all tax practitioners are adhering to codes of conduct in relation to client confidentiality. Research identifying the extent to which accounting services are outsourced is limited, therefore significant contributions to the academic literature and the accounting profession are provided by this ndicates that not all tax practitioners are adhering to codes of conduct in relation to client confidentiality. Research identifying the extent to which accounting services are outsourced is limited, therefore significant contributions to the academic literature and the accounting profession are provided by this study.

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Background The utility of GATA3 as a marker for metastatic breast carcinoma in serous effusion specimens was investigated. Methods Cell block sections from 74 serous effusion specimens (32 ascitic, 2 pericardial and 40 pleural fluids) were stained with an anti-GATA3 murine monoclonal antibody. The specimens included 62 confirmed metastatic carcinomas from breast (30), female genital tract (13), gastrointestinal tract (7), lung adenocarcinoma (9), pancreas (1), kidney (1) and bladder (1). The breast carcinoma cases included 15 ductal carcinomas, 8 lobular carcinomas and in 7 the histology sub-type was not available. Twelve cases containing florid reactive mesothelial cells were also stained. The breast carcinoma cases were also stained for mammaglobin and GCDFP-15 to compare sensitivity with GATA3. Results Positive nuclear staining for GATA3 was present in 90% (27/30) of metastatic breast carcinoma specimens. All non-breast metastatic carcinomas tested were negative with the exception of the single case of metastatic urothelial carcinoma. No staining was observed in any of the benign reactive cases or in benign mesothelial cells present in the malignant cell block preparations. Two cases showed weak positivity of benign lymphoid cells. Staining results were unambiguous as all positive cases showed intense nuclear staining in >50% of tumor cells. Mammaglobin (57%; 17/30) and GCDFP-15 (33%; 10/30) were less sensitive markers of breast carcinoma. If used in a panel, mammaglobin and GCFP-15 staining would have identified only one additional case to those stained with GATA3. Conclusions GATA3 may be a useful addition to immunostaining panels for serous effusion specimens when metastatic breast carcinoma is a consideration.

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For users of germplasm collections, the purpose of measuring characterization and evaluation descriptors, and subsequently using statistical methodology to summarize the data, is not only to interpret the relationships between the descriptors, but also to characterize the differences and similarities between accessions in relation to their phenotypic variability for each of the measured descriptors. The set of descriptors for the accessions of most germplasm collections consists of both numerical and categorical descriptors. This poses problems for a combined analysis of all descriptors because few statistical techniques deal with mixtures of measurement types. In this article, nonlinear principal component analysis was used to analyze the descriptors of the accessions in the Australian groundnut collection. It was demonstrated that the nonlinear variant of ordinary principal component analysis is an appropriate analytical tool because subspecies and botanical varieties could be identified on the basis of the analysis and characterized in terms of all descriptors. Moreover, outlying accessions could be easily spotted and their characteristics established. The statistical results and their interpretations provide users with a more efficient way to identify accessions of potential relevance for their plant improvement programs and encourage and improve the usefulness and utilization of germplasm collections.

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In Karanfilov v Inghams Enterprises Pty Ltd interpreted provisions of the Workcover Queensland Act 1996 as it applied to an injury occurring before 1 July 2001, i.e. prior to amendments made by the Workcover Queensland Act 2001. The decision involved the construction, in particular, of sections 312 and 315 of the Act

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We present a novel implementation of the threshold RSA. Our solution is conceptually simple, and leads to an easy design of the system. The signing key is shared in additive form, which is desirable for collaboratively performing cryptographic transformations, and its size, at all times, is logn, where n is the RSA modulus. That is, the system is ideal.

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The phylogenetic relationships of the beetle superfamily Tenebrionoidea are investigated using the most comprehensive genetic data set compiled to date. With ∼34,000 described species in approximately 1250 genera and 28 families, Tenebrionoidea represent one of the most diverse and species-rich superfamilies of beetles. The interfamilial relationships of the Tenebrionoidea are poorly known; previous morphological and molecular phylogenies recovered few well-supported and often conflicting relationships between families. Here we present a molecular phylogeny of Tenebrionoidea based on genes commonly used to resolve family and superfamily-level phylogenies of beetles (18S, 28S, 16S, 12S, tRNA Val and COI). The alignment spanned over 6.5 KB of DNA sequence and over 300 tenebrionoid genera from 24 of the 28 families were sampled. Maximum Likelihood and Bayesian analysis could not resolve deeper level divergences within the superfamily and very few relationships between families were supported. Increasing gene coverage in the alignment by removing taxa with missing data did not improve clade support but when rogue taxa were removed increased resolution was recovered. Investigation of signal strength suggested conflicting phylogenetic signal was present in the standard genes used for beetle phylogenetics, even when rogue taxa were removed. Our study of Tenebrionoidea highlights that even with relatively comprehensive taxon sampling within a lineage, this standard set of genes is unable to resolve relationships within this superfamily.

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Tobacco smoking, alcohol drinking, and occupational exposures to polycyclic aromatic hydrocarbons are the major proven risk factors for human head and neck squamous-cell cancer (HNSCC). Major research focus on gene-environment interactions concerning HNSCC has been on genes encoding enzymes of metabolism for tobacco smoke constituents and repair enzymes. To investigate the role of genetically determined individual predispositions in enzymes of xenobiotic metabolism and in repair enzymes under the exogenous risk factor tobacco smoke in the carcinogenesis of HNSCC, we conducted a case-control study on 312 cases and 300 noncancer controls. We focused on the impact of 22 sequence variations in CYP1A1, CYP1B1, CYP2E1, ERCC2/XPD, GSTM1, GSTP1, GSTT1, NAT2, NQO1, and XRCC1. To assess relevant main and interactive effects of polymorphic genes on the susceptibility to HNSCC we used statistical models such as logic regression and a Bayesian version of logic regression. In subgroup analysis of nonsmokers, main effects in ERCC2 (Lys751Gln) C/C genotype and combined ERCC2 (Arg156Arg) C/A and A/A genotypes were predominant. When stratifying for smokers, the data revealed main effects on combined CYP1B1 (Leu432Val) C/G and G/G genotypes, followed by CYP1B1 (Leu432Val) G/G genotype and CYP2E1 (-70G>T) G/T genotype. When fitting logistic regression models including relevant main effects and interactions in smokers, we found relevant associations of CYP1B1 (Leu432Val) C/G genotype and CYP2E1 (-70G>T) G/T genotype (OR, 10.84; 95% CI, 1.64-71.53) as well as CYP1B1 (Leu432Val) G/G genotype and GSTM1 null/null genotype (OR, 11.79; 95% CI, 2.18-63.77) with HNSCC. The findings underline the relevance of genotypes of polymorphic CYP1B1 combined with exposures to tobacco smoke.

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Cryo-electron tomography together with averaging of sub-tomograms containing identical particles can reveal the structure of proteins or protein complexes in their native environment. The resolution of this technique is limited by the contrast transfer function (CTF) of the microscope. The CTF is not routinely corrected in cryo-electron tomography because of difficulties including CTF detection, due to the low signal to noise ratio, and CTF correction, since images are characterised by a spatially variant CTF. Here we simulate the effects of the CTF on the resolution of the final reconstruction, before and after CTF correction, and consider the effect of errors and approximations in defocus determination. We show that errors in defocus determination are well tolerated when correcting a series of tomograms collected at a range of defocus values. We apply methods for determining the CTF parameters in low signal to noise images of tilted specimens, for monitoring defocus changes using observed magnification changes, and for correcting the CTF prior to reconstruction. Using bacteriophage PRDI as a test sample, we demonstrate that this approach gives an improvement in the structure obtained by sub-tomogram averaging from cryo-electron tomograms.

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Electropermeabilization (EP) is an effective method of gene transfer into different tissues. During EP, reactive oxygen species (ROS) are formed, which could affect transfection efficiency. The role of generated ROS and the role of antioxidants in electrotransfer in myoblasts in vitro and in Musculus tibialis cranialis in mice were, therefore, investigated. We demonstrate in the study that during EP of C2C12 myoblasts, ROS are generated on the surface of the cells, which do not induce long-term genomic DNA damage. Plasmid DNA for transfection (pEGFP-N1), which is present outside the cells during EP, neutralizes the generated ROS. The ROS generation is proportional to the amplitude of the electric pulses and can be scavenged by antioxidants, such as vitamin C or tempol. When antioxidants were used during gene electrotransfer, the transfection efficiency of C2C12 myoblasts was statistically significantly increased 1.6-fold with tempol. Also in vivo, the transfection efficiency of M. tibialis cranialis in mice was statistically significantly increased 1.4-fold by tempol. The study indicates that ROS are generated on cells during EP and can be scavenged by antioxidants. Specifically, tempol can be used to improve gene electrotransfer into the muscle and possibly also to other tissues.

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Purpose: To examine the extent to which socio-demographic characteristics, modifiable lifestyle factors and health status influence the mental health of midlife and older Australian women from the Australian Healthy Aging of Women (HOW) study. Methods: Data on health status, chronic disease and modifiable lifestyle factors were collected from a random sample of 340 women aged 40-65 years, residing in Queensland, Australia in 2011. Structural equation modelling (SEM) was used to measure the effect of a range of socio-demographic characteristics (marital status, age, income), modifiable lifestyle factors (caffeine intake, alcohol consumption, exercise, physical activity, sleep), and health markers (self-reported physical health, history of chronic illness) on the latent construct, mental health. Mental health was evaluated using the Medical Outcomes Study Short Form 12 (SF-12®) and the Center for Epidemiologic Studies Depression Scale (CES-D). Results: The model was a good fit for the data (χ2 = 40.166, df =312, p 0.125, CFI = 0.976, TLI = 0.950, RMSEA = 0.030, 90% CI = 0.000-0.053); the model suggested mental health was negatively influenced by sleep disturbance (β = -0.628), sedentary lifestyle (β = -0.137), having been diagnosed with one or more chronic illnesses (β = -0.203), and poor self-reported physical health (β = - 0.161). While mental health was associated with sleep, it was not correlated with many other lifestyle factors (BMI (β = -0.050), alcohol consumption (β = 0.079), or cigarette smoking (β = 0.008)) or background socio-demographic characteristics (age (β = 0.078), or income (β = -0.039)). Conclusion: While research suggests that it is important to engage in a range health promoting behaviours to preserve good health, we found that only sleep disturbance, physical health, chronic illness and level of physical activity predicted current mental health. However, while socio-demographic characteristics and modifiable lifestyle factors seemed to have little direct impact on mental health, they probably had an indirect effect.

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This chapter offers three insights into the relationship between curriculum decision making, positive school climate, and academic achievement for same-sex attracted (SSA) students, highlighting the need for students to be offered more than heteronormative narratives and silence on issues of sexuality in the official school curriculum. The authors firstly provide a review of research and report on findings of a doctoral study (Mikulsky, 2007) explaining the impact of SSA students’ perceptions of school climate on their motivation and academic self-concept. Situating the work in the context of the Australian Curriculum for English and associated classroom texts, the dominant discourse of ‘straight, white female’ heroines as exemplified in the globally popular young adult novel The hunger games and other texts popular with Australian students are critiqued, with an argument made for expanding notions of what it means to ‘attend to’ gender and sexuality through textual choice and critical pedagogy. The authors show how texts that feature LGBTQ characters and storylines continue to be marginalized and constructed as taboo and demonstrate how curricular choices can and do impact academic outcomes for marginalized students. Issues of gender and sexuality are framed as a cross-curriculum imperative, with recommendations made for the explicit inclusion of materials exploring gender and sexuality in the official curriculum of all key learning areas.

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Few would disagree that the upstream oil & gas industry has become more technology-intensive over the years. But how does innovation happen in the industry? Specifically, what ideas and inputs flow from which parts of the sector׳s value network, and where do these inputs go? And how do firms and organizations from different countries contribute differently to this process? This paper puts forward the results of a survey designed to shed light on these questions. Carried out in collaboration with the Society of Petroleum Engineers (SPE), the survey was sent to 469 executives and senior managers who played a significant role with regard to R&D and/or technology deployment in their respective business units. A total of 199 responses were received from a broad range of organizations and countries around the world. Several interesting themes and trends emerge from the results, including: (1) service companies tend to file considerably more patents per innovation than other types of organization; (2) over 63% of the deployed innovations reported in the survey originated in service companies; (3) neither universities nor government-led research organizations were considered to be valuable sources of new information and knowledge in the industry׳s R&D initiatives, and; (4) despite the increasing degree of globalization in the marketplace, the USA still plays an extremely dominant role in the industry׳s overall R&D and technology deployment activities. By providing a detailed and objective snapshot of how innovation happens in the upstream oil & gas sector, this paper provides a valuable foundation for future investigations and discussions aimed at improving how R&D and technology deployment are managed within the industry. The methodology did result in a coverage bias within the survey, however, and the limitations arising from this are explored.