611 resultados para Primary history


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Large igneous provinces (LIPs) host the most frequently recurring, largest volume basaltic & silicic eruptions on Earth. The largest volume (>1000 km^3 DRE) and magnitude (>M8) eruptions produce areally extensive (10^4-10^5 km^2) basaltic flow fields and sills, and silicic ignimbrites that are the main LIP building blocks. Basaltic and silicic eruptions have comparable magnitudes, but silicic ignimbrite volumes may be significantly underestimated due to unrecognized and correlated, but voluminous co-ignimbrite ash deposits. Magma composition is no barrier to individual eruption volume. Despite similar magnitudes, flood basaltic and silicic eruptions are very different in eruption mechanism, duration, intensity, vent configuration, and emplacement style. Flood basalts are dominantly effusive Hawaiian-Strombolian, with magma discharge rates of ~10^7-10^8 kg s^-1, and produce dominantly compound pahoehoe flow fields over eruption durations most likely >10 yrs. Most silicic eruptions are moderately to highly explosive, producing cocurrent pyroclastic fountains (rarely Plinian) and suggested to be of short-duration (hours to days) and high intensity (~10^11 kg s^-1). Eruption frequencies are elevated for largemagnitude eruptions of both magma types during LIP formation. In basalt-dominated provinces, large magnitude (>M8) eruptions have much shorter recurrence intervals (10^3-10^4 years) than similar magnitude silicic eruptions (~10^5 years). The huge volumes of magma erupted rapidly in LIPs raises several unresolved issues in terms of locus of magma generation and storage (if any) in the crust prior to eruption, the paths and rates of ascent from magma reservoirs to the surface, and relative aerosol contributions to the stratosphere from the flood basaltic and rhyolitic eruptions.

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Background Predicting protein subnuclear localization is a challenging problem. Some previous works based on non-sequence information including Gene Ontology annotations and kernel fusion have respective limitations. The aim of this work is twofold: one is to propose a novel individual feature extraction method; another is to develop an ensemble method to improve prediction performance using comprehensive information represented in the form of high dimensional feature vector obtained by 11 feature extraction methods. Methodology/Principal Findings A novel two-stage multiclass support vector machine is proposed to predict protein subnuclear localizations. It only considers those feature extraction methods based on amino acid classifications and physicochemical properties. In order to speed up our system, an automatic search method for the kernel parameter is used. The prediction performance of our method is evaluated on four datasets: Lei dataset, multi-localization dataset, SNL9 dataset and a new independent dataset. The overall accuracy of prediction for 6 localizations on Lei dataset is 75.2% and that for 9 localizations on SNL9 dataset is 72.1% in the leave-one-out cross validation, 71.7% for the multi-localization dataset and 69.8% for the new independent dataset, respectively. Comparisons with those existing methods show that our method performs better for both single-localization and multi-localization proteins and achieves more balanced sensitivities and specificities on large-size and small-size subcellular localizations. The overall accuracy improvements are 4.0% and 4.7% for single-localization proteins and 6.5% for multi-localization proteins. The reliability and stability of our classification model are further confirmed by permutation analysis. Conclusions It can be concluded that our method is effective and valuable for predicting protein subnuclear localizations. A web server has been designed to implement the proposed method. It is freely available at http://bioinformatics.awowshop.com/snlpr​ed_page.php.

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A novel multiple regression method (RM) is developed to predict identity-by-descent probabilities at a locus L (IBDL), among individuals without pedigree, given information on surrounding markers and population history. These IBDL probabilities are a function of the increase in linkage disequilibrium (LD) generated by drift in a homogeneous population over generations. Three parameters are sufficient to describe population history: effective population size (Ne), number of generations since foundation (T), and marker allele frequencies among founders (p). IBD L are used in a simulation study to map a quantitative trait locus (QTL) via variance component estimation. RM is compared to a coalescent method (CM) in terms of power and robustness of QTL detection. Differences between RM and CM are small but significant. For example, RM is more powerful than CM in dioecious populations, but not in monoecious populations. Moreover, RM is more robust than CM when marker phases are unknown or when there is complete LD among founders or Ne is wrong, and less robust when p is wrong. CM utilises all marker haplotype information, whereas RM utilises information contained in each individual marker and all possible marker pairs but not in higher order interactions. RM consists of a family of models encompassing four different population structures, and two ways of using marker information, which contrasts with the single model that must cater for all possible evolutionary scenarios in CM.

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Objectives: Smoking cessation has been shown to be an important intervention for preventing cardiovascular events and improving the health of patients with heart disease. However, unaided quit attempts in these patients often leads to high rates of failure and a return to smoking. Outpatient smoking cessation clinics using face-to-face counseling, ongoing behavioral support, advice on smoking pharmacotherapy and objective monitoring, have been found to be one of the most effective interventions for improving quit smoking rates. An outpatient smoking cessation clinic was trialed within a cardiac rehabilitation service in order to explore its effects on smoking rates for patients with or at risk of heart disease. Attendance rates to the clinic were also monitored. Methods: A descriptive exploratory design was used for this newly developed clinic. Patients who currently smoked tobacco and who had a history of either coronary artery disease, heart failure, atrial fibrillation or those seen under a chest pain assessment service were invited to an outpatient ‘Cardiac Patients Smokers Clinic’. Initially patients were offered up to 10 clinic visits over a 3 month period. Follow-up clinic visits were conducted at 3, 6 and 12 months. A portable carbon monoxide meter was used to objectively measure levels of smoking and validate smoking abstinence. Primary outcomes included rates of attendance. Results: Preliminary findings showed 24 per cent of participants (N = 6) completed all their clinic visits and remained smoke free as measured by their ongoing expired carbon monoxide readings. Clinic attendance rates appeared lowest for those with significant mental health issues such as schizophrenia or substance abuse. However, rates of attendance were improved by having an administration officer make reminder telephone calls prior to clinic visits. Conclusions: Early findings indicate the feasibility of providing a specialist smoking cessation clinic within a cardiac rehabilitation service. Further, that reminder telephone calls prior to appointments improved attendance rates in patients with heart disease to this type of clinic. However, future investigations are warranted.

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Modern and Postmodern Los Angeles is examined through the lens of film noir and neo noir. The unique relationship between the city of Los Angeles and cinema is discussed in terms of a historiography emphasizing the role played by these defining film styles and genres. The research draws and extends on the work conducted by Edward Dimendberg, Paula Rabinowitz and Mike Davis, and urban theory approaches associated with the Los Angeles School of Urbanism.

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This paper considers how Asia can be meaningfully studied and understood in the first national history curriculum to be implemented in Australia. Its focus is on how empathy might be conceptualised as part of the process of becoming ‘Asia literate’ and the ways in which an empathetic understanding can be developed in the Australian Curriculum: History by engaging students with children’s literature. We argue that stories about Chinese experiences in Australia from particular episodes in the nation’s past can be utilised for their potential to prompt historical inquiry and empathetic engagement in the classroom.

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Background: There is a well developed literature on research investigating the relationship between various driving behaviours and road crash involvement. However, this research has predominantly been conducted in developed economies dominated by western types of cultural environments. To date no research has been published that has empirically investigated this relationship within the context of the emerging economies such as Oman. Objective: The present study aims to investigate driving behaviour as indexed in the Driving Behaviour Questionnaire (DBQ) among a group of Omani university students and staff. Methods: A convenience non-probability self- selection sampling approach was utilized with Omani university students and staff. Results: A total of 1003 Omani students (n= 632) and staff (n=371) participated in the survey. Factor analysis of the BDQ revealed four main factors that were errors, speeding violation, lapses and aggressive violation. In the multivariate logistic backward regression analysis, the following factors were identified as significant predictors of being involved in causing at least one crash: driving experience, history of offences and two DBQ components i.e. errors and aggressive violation. Conclusion: This study indicates that errors and aggressive violation of the traffic regulations as well as history of having traffic offences are major risk factors for road traffic crashes among the sample. While previous international research has demonstrated that speeding is a primary cause of crashing, in the current context, the results indicate that an array of factors is associated with crashes. Further research using more rigorous methodology is warranted to inform the development of road safety countermeasures in Oman that improves overall traffic safety culture.

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Eleven Pro-Am curators of Australian television history were interviewed about their practice. The data helps us to understand the relationship between professional and Pro-Am approaches to Australian television history. There is no simple binary – the lines are blurred – but there are some differences. Pro-Am curators of Australian television history are not paid for their work and present other motivations for practice – particularly being that ‘weird child’ who was obsessed with gathering information and objects related to television. They have freedom to curate only programs and genres that interest them, and they tend to collect merchandise as much as program texts themselves. And they have less interest in formally cataloguing their material than do professional curators of Australian television history.

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Objective: To investigate the density of the primary epidermal lamellae (PEL) around the solar circumference of the forefeet of near-term fetal feral and nonferal (ie, domesticated) horses. Sample: Left forefeet from near-term Australian feral (n = 14) and domesticated (4) horse fetuses. Procedures: Near-term feral horse fetuses were obtained from culled mares within 10 minutes of death; fetuses that had died in utero 2 weeks prior to anticipated birth date and were delivered from live Thoroughbred mares were also obtained. Following disarticulation at the carpus, the left forefoot of each fetus was frozen during dissection and data collection. In a standard section of each hoof, the stratum internum PEL density was calculated at the midline center (12 o'clock) and the medial and lateral break-over points (11 and 1 o'clock), toe quarters (10 and 2 o'clock), and quarters (4 and 6 o'clock). Values for matching lateral and medial zones were averaged and expressed as 1 density. Density differences at the 4 locations between the feral and domesticated horse feet were assessed by use of imaging software analysis. Results: In fetal domesticated horse feet, PEL density did not differ among the 4 locations. In fetal feral horse feet, PEL density differed significantly among locations, with a pattern of gradual reduction from the dorsal to the palmar aspect of the foot. The PEL density distribution differed significantly between fetal domesticated and feral horse feet. Conclusions and Clinical Relevance: Results indicated that PEL density distribution differs between fetal feral and domesticated horse feet, suggestive of an adaptation of feral horses to environment challenges.

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The present study examined the historical basis of the Australian disability income support system from 1908 to 2007. Although designed as a safety net for people with a disability, the disability income support system within Australia has been highly targeted. The original eligibility criteria of "permanently incapacitated for work", medical criteria and later "partially capacitated for work" potentially contained ideological inferences that permeated across the time period. This represents an important area for study given the potential consequence for disability income support to marginalise people with a disability. Social policy and disability policy theorists, including Saunders (2007, Social Policy Research Centre [SPRC]) and Gibilisco (2003) have provided valuable insight into some of the effects of disability policy and poverty. Yet while these theorists argued for some form of income support they did not propose a specific form of income security for further exploration. Few studies have undertaken a comprehensive review of the history of disability income support within the Australian context. This thesis sought to redress these gaps by examining disability income support policy within Australia. The research design consisted of an in-depth critical historical-comparative policy analysis methodology. The use of critical historical-comparative policy analysis allowed the researcher to trace the construction of disability within the Australian disability income support policy across four major historical epochs. A framework was developed specifically to guide analysis of the data. The critical discourse analysis method helped to understand the underlying ideological dimensions that led to the predominance of one particular approach over another. Given this, the research purpose of the study centred on: i. Tracing the history of the Australian disability income support system. ii. Examining the historical patterns and ideological assumptions over time. iii. Exploring the historical patterns and ideological assumptions underpinning an alternative model (Basic Income) and the extent to which each model promotes the social citizenship of people with a disability. The research commitment to a social-relational ontology and the quest for social change centred on the idea that "there has to be a better way" in the provision of disability income support. This theme of searching for an alternative reality in disability income support policy resonated throughout the thesis. This thesis found that the Australian disability income support system is disabling in nature and generates categories of disability on the basis of ableness. From the study, ableness became a condition for citizenship. This study acknowledged that, in reality, income support provision reflects only one aspect of the disabling nature of society which requires redressing. Although there are inherent tensions in any redistributive strategy, the Basic Income model potentially provides an alternative to the Australian disability income support system, given its grounding in social citizenship. The thesis findings have implications for academics, policy-makers and practitioners in terms of developing better ways to understand disability constructs in disability income support policy. The thesis also makes a contribution in terms of promoting income support policies based on the rights of all people, not just a few.

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Ian Hunter's early work on the history of literature education and the emergence of English as school subject issued a bold challenge to traditional accounts that have in the main focused on English either as knowledge of a particular field or as ideology. The alternative proposal put forward by Hunter and supported by detailed historical analysis is that English exists as a series of historically contingent techniques and practices for shaping the self-managing capacities of children. The challenge for the field is to advance this historical work and to examine possible implications for English teaching.

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We propose a multi-layer spectrum sensing optimisation algorithm to maximise sensing efficiency by computing the optimal sensing and transmission durations for a fast changing, dynamic primary user. Dynamic primary user traffic is modelled as a random process, where the primary user changes states during both the sensing period and transmission period to reflect a more realistic scenario. Furthermore, we formulate joint constraints to correctly reflect interference to the primary user and lost opportunity of the secondary user during the transmission period. Finally, we implement a novel duty cycle based detector that is optimised with respect to PU traffic to accurately detect primary user activity during the sensing period. Simulation results show that unlike currently used detection models, the proposed algorithm can jointly optimise the sensing and transmission durations to simultaneously satisfy the optimisation constraints for the considered primary user traffic.

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Between 1995 and 2003, 129 cemented primary THRs were performed using full acetabular impaction grafting to reconstruct acetabular deficiencies. These were classified as cavitary in 74 and segmental in 55 hips. Eighty-one patients were reviewed at mean 9.1 (6.2-14.3) years post-operatively. There were seven acetabular component revisions due to aseptic loosening, and a further 11 cases that had migrated >5mm or tilted >5° on radiological review - ten of which reported no symptoms. Kaplan-Meier analysis of revisions for aseptic loosening demonstrates 100% survival at nine years for cavitary defects compared to 82.6% for segmental defects. Our results suggest that the medium-term survival of this technique is excellent when used for purely cavitary defects but less predictable when used with large rim meshes in segmental defects.

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An important subset of extraterrestrial particles that reach the Earth's stratosphere include the so-called Chondritic Porous Aggregates (CPA's) [1-3]. In general, CPA's have a fluffy morphology and consist of numerous (>104)subparticles that are often <100A in size [4]. Mineral species in CPA's include Mg-rich pyroxene and olivine, Fe- and (Fe,Ni)-sulphides, taenite, Fe,Ni-carbides, magnetite, Ti-metal, a Bi-phase (metal or oxide), and variable amounts of carbonaceous material [1, 5-7]. Hydrated silicates are rare in CPA's and are limited to aggregates that have not been severely altered (thermo-metamorphosed) during atmospheric entry [8]. The presence of hydrated silicates in one cosmic dust particle was established by X-ray diffraction [2] and has been inferred in others by infra-red spectroscopy [8]. If CPA's are cometary, their mineralogy and morphology suggest that at least two episodes of aggregation occurred and that variations in porosity may be related to local differences in ice-to-dust ratio [3].

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This study investigated the relationships between knowledge and efficacy for teaching sustainability in a sample of 266 pre-service primary teachers at a large, metropolitan university in Australia. A survey gathered information about the participant’s attitudes and self-efficacy for education for sustainability, along with their perceived and actual knowledge of environmental sustainability issues. The participants typically believed they were confident in their abilities to engage with education for sustainability with self-efficacy increasing with increased levels of perceived knowledge. However no relationship was found between perceived knowledge and actual knowledge which suggests that the participants either do not feel constrained by their lack of knowledge, or are perhaps unaware of their actual knowledge of sustainability issues. This lack of relationship may have implications for the development of pedagogical content knowledge with pre-service teachers potentially developing shallow, tokenistic approaches to Education for Sustainability.