941 resultados para Single-stage inverters


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Objective: To perform a 1-stage meta-analysis of genome-wide association studies (GWAS) of multiple sclerosis (MS) susceptibility and to explore functional consequences of new susceptibility loci. Methods: We synthesized 7 MS GWAS. Each data set was imputed using HapMap phase II, and a per single nucleotide polymorphism (SNP) meta-analysis was performed across the 7 data sets. We explored RNA expression data using a quantitative trait analysis in peripheral blood mononuclear cells (PBMCs) of 228 subjects with demyelinating disease. Results: We meta-analyzed 2,529,394 unique SNPs in 5,545 cases and 12,153 controls. We identified 3 novel susceptibility alleles: rs170934T at 3p24.1 (odds ratio [OR], 1.17; p ¼ 1.6 � 10�8) near EOMES, rs2150702G in the second intron of MLANA on chromosome 9p24.1 (OR, 1.16; p ¼ 3.3 � 10�8), and rs6718520A in an intergenic region on chromosome 2p21, with THADA as the nearest flanking gene (OR, 1.17; p ¼ 3.4 � 10�8). The 3 new loci do not have a strong cis effect on RNA expression in PBMCs. Ten other susceptibility loci had a suggestive p < 1 � 10�6, some of these loci have evidence of association in other inflammatory diseases (ie, IL12B, TAGAP, PLEK, and ZMIZ1). Interpretation: We have performed a meta-analysis of GWAS in MS that more than doubles the size of previous gene discovery efforts and highlights 3 novel MS susceptibility loci. These and additional loci with suggestive evidence of association are excellent candidates for further investigations to refine and validate their role in the genetic architecture of MS.

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In the mammary gland, Wnt signals are strongly implicated in initial development of the mammary rudiments and in the ductal branching and alveolar morphogenesis that occurs during pregnancy. Previously, we identified two Wnt signaling pathway-implicated genes, PPP3CA and MARK4, as having a role in more aggressive and potentially metastatic breast tumors. In this study, we examined two SNPs within PPP3CA and MARK4 in an Australian case-control study population for a potential role in human breast cancers. 182 cases and 180 controls were successfully genotyped for the PPP3CA SNP (rs2850328) and 182 cases and 177 controls were successfully genotyped for the MARK4 SNP (rs2395) using High Resolution Melt (HRM) analysis. Genotypes of randomly selected samples for both SNPs were validated by dye terminator sequencing. Chi-square tests were performed to determine any significant differences in the genotype and allele frequencies between the cases and controls. Chi-square analysis showed no statistically significant difference (p > .05) for genotype frequencies between cases and controls for rs2850328 (χ2 = 1.2, p = .5476) or rs2395 (χ2 = .3, p = .8608). Similarly, no statistical difference was observed for allele frequencies for rs2850328 (χ2 = .68, p = .4108) or rs2395 (χ2 = .02, p = .893). Even though an association of the polymorphisms rs2850328 and rs2395 and breast cancer was not detected in our case-control study population, other variants within the PPP3CA and MARK4 genes may still be associated with breast cancer, as both genes are implicated with processes involved in the disease as well as their mutual partaking in the Wnt signaling pathway.

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microRNAs are small, non-coding RNAs that influence gene expression on a post-transcriptional level. They participate in diverse biological pathways and may act as either tumor suppressor genes or oncogenes. As they may have an effect on thousands of target mRNAs, single-nucleotide polymorphisms in microRNA genes might have major functional consequences, because the microRNA's properties and/or maturation may change. miR-196a has been reported to be aberrantly expressed in breast cancer tissue. Additionally, the SNP rs11614913 in hsa-mir-196a-2 has been found to be associated with breast cancer risk in some studies although not in others. This study evaluated the association between rs11614913 and breast cancer risk in a Caucasian case-control cohort in Queensland, Australia. Results do not support an association of the tested hsa-mir-196a-2 polymorphism with breast cancer susceptibility in this cohort. As there is a discrepancy between our results and previous findings, it is important to assess the role of rs11614913 in breast cancer by further larger studies investigating different ethnic groups.

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Emergency service workers (e.g., fire-fighters, police and paramedics) are exposed to elevated levels of potentially traumatising events through the course of their work. Such exposure can have lasting negative consequences (e. g., Post Traumatic Stress Disorder; PTSD) and/or positive outcomes (e. g., Posttraumatic Growth; PTG). Research had implicated trauma, occupational and personal variables that account for variance in post-trauma outcomes yet at this stage no research has investigated these factors and their relative influence on both PTSD and PTG in a single study. Based in Calhoun and Tedeschi’s (2013) model of PTG and previous research, in this study regression models of PTG and PTSD symptoms among 218 fire-fighters were tested. Results indicated organisational factors predicted symptoms of PTSD, while there was partial support for the hypothesis that coping and social support would be predictors of PTG. Experiencing multiple sources of trauma, higher levels of organisational and operational stress, and utilising cognitive reappraisal coping, were all significant predictors of PTSD symptoms. Increases in PTG were predicted by experiencing trauma from multiple sources and the use of self-care coping. Results highlight the importance of organisational factors in the development of PTSD symptoms, and of individual factors for promoting PTG.

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Migraine is a common debilitating primary headache disorder with significant mental, physical and social health implications. The brain neurotransmitter 5-hydroxytryptamine (5-HT; serotonin) is involved in nociceptive pathways and has been implicated in the pathophysiology of migraine. With few genetic studies investigating biosynthetic and metabolic enzymes governing the rate of 5-HT activity and their relationship to migraine, it was the objective of this study to assess genetic variants within the human tryptophan hydroxylase (TPH), amino acid decarboxylase (AADC) and monoamine oxidase A (MAOA) genes in migraine susceptibility. This objective was undertaken using a high-throughput DNA pooling experimental design, which proved to be a very accurate, sensitive and specific method of estimating allele frequencies for single nucleotide polymorphism, insertion deletion and variable number tandem repeat loci. Application of DNA pooling to a wide array of genetic loci provides greater scope in the assessment of population-based genetic association study designs. Despite the application of this high-throughput genotyping method, negative results from the two-stage DNA pooling design used to screen loci within the TPH, AADC and MAOA genes did not support their role in migraine susceptibility.

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We have identified a migraine locus on chromosome 19p13.3/2 using linkage and association analysis. We isolated 48 single-nucleotide polymorphisms within the locus, of which we genotyped 24 in a Caucasian population comprising 827 unrelated cases and 765 controls. Five single-nucleotide polymorphisms within the insulin receptor gene showed significant association with migraine. This association was independently replicated in a case-control population collected separately. We used experiments with insulin receptor RNA and protein to investigate functionality for the migraine-associated single-nucleotide polymorphisms. We suggest possible functions for the insulin receptor in migraine pathogenesis.

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This paper examines ‘green’ entrepreneurial nascent and young firms in Australia. Findings of interest in this paper include: • Green entrepreneurs are more likely to be highly educated and have an extended depth of experience within their industry and are more likely to have started a business prior to their current venture. • Green entrepreneurs exhibit increased levels of innovation, with an increased focus on new & high technology, R&D and the development of proprietary technology. • Green entrepreneurs are most likely to be based upon a product rather than a service and have a higher emphasis upon growth when compared with non-green entrepreneurs. • Green entrepreneurial firms tend to have a longer venture creation process and draw financial resources from a larger number of sources and rely more upon equity as a means of financing their venture.

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Network reconfiguration after complete blackout of a power system is an essential step for power system restoration. A new node importance evaluation method is presented based on the concept of regret, and maximisation of the average importance of a path is employed as the objective of finding the optimal restoration path. Then, a two-stage method is presented to optimise the network reconfiguration strategy. Specifically, the restoration sequence of generating units is first optimised so as to maximise the restored generation capacity, then the optimal restoration path is selected to restore the generating nodes concerned and the issues of selecting a serial or parallel restoration mode and the reconnecting failure of a transmission line are next considered. Both the restoration path selection and skeleton-network determination are implemented together in the proposed method, which overcomes the shortcoming of separate decision-making in the existing methods. Finally, the New England 10-unit 39-bus power system and the Guangzhou power system in South China are employed to demonstrate the basic features of the proposed method.

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With an increased emphasis on genotyping of single nucleotide polymorphisms (SNPs) in disease association studies, the genotyping platform of choice is constantly evolving. In addition, the development of more specific SNP assays and appropriate genotype validation applications is becoming increasingly critical to elucidate ambiguous genotypes. In this study, we have used SNP specific Locked Nucleic Acid (LNA) hybridization probes on a real-time PCR platform to genotype an association cohort and propose three criteria to address ambiguous genotypes. Based on the kinetic properties of PCR amplification, the three criteria address PCR amplification efficiency, the net fluorescent difference between maximal and minimal fluorescent signals and the beginning of the exponential growth phase of the reaction. Initially observed SNP allelic discrimination curves were confirmed by DNA sequencing (n = 50) and application of our three genotype criteria corroborated both sequencing and observed real-time PCR results. In addition, the tested Caucasian association cohort was in Hardy-Weinberg equilibrium and observed allele frequencies were very similar to two independently tested Caucasian association cohorts for the same tested SNP. We present here a novel approach to effectively determine ambiguous genotypes generated from a real-time PCR platform. Application of our three novel criteria provides an easy to use semi-automated genotype confirmation protocol.

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The production of adequate agricultural outputs to support the growing human population places great demands on agriculture, especially in light of ever-greater restrictions on input resources. Sorghum is a drought-adapted cereal capable of reliable production where other cereals fail, and thus represents a good candidate to address food security as agricultural inputs of water and arable land grow scarce. A long-standing issue with sorghum grain is that it has an inherently lower digestibility. Here we show that a low-frequency allele type in the starch metabolic gene, pullulanase, is associated with increased digestibility, regardless of genotypic background. We also provide evidence that the beneficial allele type is not associated with deleterious pleiotropic effects in the modern field environment. We argue that increasing the digestibility of an adapted crop is a viable way forward towards addressing food security while maximizing water and land-use efficiency.

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High-speed broadband internet access is widely recognised as a catalyst to social and economic development. However, the provision of broadband Internet services with the existing solutions to rural population, scattered over an extensive geographical area, remains both an economic and technical challenge. As a feasible solution, the Commonwealth Scientific and Industrial Research Organization (CSIRO) proposed a highly spectrally efficient, innovative and cost-effective fixed wireless broadband access technology, which uses analogue TV frequency spectrum and Multi-User MIMO (MUMIMO) technology with Orthogonal-Frequency-Division-Multiplexing (OFDM). MIMO systems have emerged as a promising solution for the increasing demand of higher data rates, better quality of service, and higher network capacity. However, the performance of MIMO systems can be significantly affected by different types of propagation environments e.g., indoor, outdoor urban, or outdoor rural and operating frequencies. For instance, large spectral efficiencies associated with MIMO systems, which assume a rich scattering environment in urban environments, may not be valid for all propagation environments, such as outdoor rural environments, due to the presence of less scatterer densities. Since this is the first time a MU-MIMO-OFDM fixed broadband wireless access solution is deployed in a rural environment, questions from both theoretical and practical standpoints arise; For example, what capacity gains are available for the proposed solution under realistic rural propagation conditions?. Currently, no comprehensive channel measurement and capacity analysis results are available for MU-MIMO-OFDM fixed broadband wireless access systems which employ large scale multiple antennas at the Access Point (AP) and analogue TV frequency spectrum in rural environments. Moreover, according to the literature, no deterministic MU-MIMO channel models exist that define rural wireless channels by accounting for terrain effects. This thesis fills the aforementioned knowledge gaps with channel measurements, channel modeling and comprehensive capacity analysis for MU-MIMO-OFDM fixed wireless broadband access systems in rural environments. For the first time, channel measurements were conducted in a rural farmland near Smithton, Tasmania using CSIRO's broadband wireless access solution. A novel deterministic MU-MIMO-OFDM channel model, which can be used for accurate performance prediction of rural MUMIMO channels with dominant Line-of-Sight (LoS) paths, was developed under this research. Results show that the proposed solution can achieve 43.7 bits/s/Hz at a Signal-to- Noise Ratio (SNR) of 20 dB in rural environments. Based on channel measurement results, this thesis verifies that the deterministic channel model accurately predicts channel capacity in rural environments with a Root Mean Square (RMS) error of 0.18 bits/s/Hz. Moreover, this study presents a comprehensive capacity analysis of rural MU-MIMOOFDM channels using experimental, simulated and theoretical models. Based on the validated deterministic model, further investigations on channel capacity and the eects of capacity variation, with different user distribution angles (θ) around the AP, were analysed. For instance, when SNR = 20dB, the capacity increases from 15.5 bits/s/Hz to 43.7 bits/s/Hz as θ increases from 10° to 360°. Strategies to mitigate these capacity degradation effects are also presented by employing a suitable user grouping method. Outcomes of this thesis have already been used by CSIRO scientists to determine optimum user distribution angles around the AP, and are of great significance for researchers and MU-MUMO-OFDM system developers to understand the advantages and potential capacity gains of MU-MIMO systems in rural environments. Also, results of this study are useful to further improve the performance of MU-MIMO-OFDM systems in rural environments. Ultimately, this knowledge contribution will be useful in delivering efficient, cost-effective high-speed wireless broadband systems that are tailor-made for rural environments, thus, improving the quality of life and economic prosperity of rural populations.

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Background: Genome-wide association studies (GWAS) have identified more than 100 genetic loci for various cancers. However, only one is for endometrial cancer. Methods: We conducted a three-stage GWAS including 8,492 endometrial cancer cases and 16,596 controls. After analyzing 585,963 single-nucleotide polymorphisms (SNP) in 832 cases and 2,682 controls (stage I) from the Shanghai Endometrial Cancer Genetics Study, we selected the top 106 SNPs for in silico replication among 1,265 cases and 5,190 controls from the Australian/British Endometrial Cancer GWAS (stage II). Nine SNPs showed results consistent in direction with stage I with P < 0.1. These nine SNPs were investigated among 459 cases and 558 controls (stage IIIa) and six SNPs showed a direction of association consistent with stages I and II. These six SNPs, plus two additional SNPs selected on the basis of linkage disequilibrium and P values in stage II, were investigated among 5,936 cases and 8,166 controls from an additional 11 studies (stage IIIb). Results: SNP rs1202524, near the CAPN9 gene on chromosome 1q42.2, showed a consistent association with endometrial cancer risk across all three stages, with ORs of 1.09 [95% confidence interval (CI), 1.03–1.16] for the A/G genotype and 1.17 (95% CI, 1.05–1.30) for the G/G genotype (P = 1.6 × 10−4 in combined analyses of all samples). The association was stronger when limited to the endometrioid subtype, with ORs (95% CI) of 1.11 (1.04–1.18) and 1.21 (1.08–1.35), respectively (P = 2.4 × 10−5). Conclusions: Chromosome 1q42.2 may host an endometrial cancer susceptibility locus. Impact: This study identified a potential genetic locus for endometrial cancer risk

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Background Exploring self management in End Stage Renal Disease is extremely important for patients as they encounter several challenges including ongoing symptoms, complex treatments and restrictions, uncertainty about life and a dependency on technology, all of which impact upon their autonomy particularly after commencement of haemodialysis. Objective To summarise the effects of nursing interventions which effect selfmanagement of haemodialysis for patients with End Stage Renal Disease. Search strategy Search terms were chosen after reviewing text words and MeSH terms in relevant articles and databases. An extensive search of the literature from 1966 to June 2009 was conducted across a range of health databases including Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, CINAHL, PsycINFO and Web of Science. Further studies were identified from reference lists of all retrieved studies. Selection criteria We considered randomised controlled trials that compared interventions to improve self management of haemodialysis in patients with ESRD. In the absence of RCTs, comparative studies without randomisation as well as before and after studies were considered for inclusion. Methodological quality Study reports selected for retrieval were assessed by two independent reviewers for methodological quality prior to inclusion in the review using the standardised critical appraisal instruments for the Joanna Briggs Institute System for the Unified Management, Assessment and Review of Information package (SUMARI). Data collection and analysis Data was extracted using the JBI data extraction tool for evidence of effectiveness independently by pairs of review authors. The evidence was reported in narrative summaries due to heterogeneity of the interventions of the studies. Results and conclusions Five randomised controlled trials were included in the review. Overall, the evidence found that psychosocial and educational interventions influenced self management of haemodialysis in this patient population.

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At the time of its official opening on 15 July 2011, The University of Queensland 1.22 MW array was the largest flat-panel PhotoVoltaic (PV) array in Australia. This PV array consists of over 5000 Trina Solar 240 Wp polycrystalline silicon PV modules installed across four rooftops at the St Lucia campus. Grid connection was achieved with 85 12.5 kW three phase and four 5 kW single phase grid connect inverters manufactured by Power-One. The site also includes one 8.4 kWp SolFocus concentrating solar 2 axis tracking PV array. Site wide monitoring and data logging of all DC, AC and environmental quantities will allow this array to be a rich source of research data. The site will also include a 200 kW 400 kWh zinc bromine energy storage system by Redflow, and associated power quality metering and monitoring. This paper presents highlights of the project feasibility study which included a site survey, shading analysis, and technology and triple bottom line assessment. A detailed description of the final technical implementation including discussion of alterative options considered is given. Finally, example initial data showing yield, trends and early example experimental results are presented.