152 research outputs found
Multi-objective engineering shape optimization using differential evolution interfaced to the Nimrod/O tool
This paper presents an enhancement of the Nimrod/O optimization tool by interfacing DEMO, an external multiobjective optimization algorithm. DEMO is a variant of differential evolution – an algorithm that has attained much popularity in the research community, and this work represents the first time that true multiobjective optimizations have been performed with Nimrod/O. A modification to the DEMO code enables multiple objectives to be evaluated concurrently. With Nimrod/O’s support for parallelism, this can reduce the wall-clock time significantly for compute intensive objective function evaluations. We describe the usage and implementation of the interface and present two optimizations. The first is a two objective mathematical function in which the Pareto front is successfully found after only 30 generations. The second test case is the three-objective shape optimization of a rib-reinforced wall bracket using the Finite Element software, Code_Aster. The interfacing of the already successful packages of Nimrod/O and DEMO yields a solution that we believe can benefit a wide community, both industrial and academic
Geographical disparities in core population coverage indicators for roll back malaria in Malawi
BACKGROUND: Implementation of known effective interventions would necessitate the reduction of malaria burden by half by the year 2010. Identifying geographical disparities of coverage of these interventions at small area level is useful to inform where greatest scaling-up efforts should be concentrated. They also provide baseline data against which future scaling-up of interventions can be compared. However, population data are not always available at local level. This study applied spatial smoothing methods to generate maps at subdistrict level in Malawi to serve such purposes. METHODS: Data for the following responses from the 2000 Malawi Demographic and Health Survey (DHS) were aggregated at subdistrict level: (1) households possessing at least one bednet; (2) children under 5 years who slept under a bednet the night before the survey; (3) bednets retreated with insecticide within past 6-12 months preceding the survey; (4) children under 5 who had fever two weeks before the survey and received treatment within 24 hours from the onset of fever; and (5) women who received intermittent preventive treatment of malaria during their last pregnancy. Each response was geographically smoothed at subdistrict level by applying conditional autoregressive models using Markov Chain Monte Carlo simulation techniques. RESULTS: The underlying geographical patterns of coverage of indicators were more clear in the smoothed maps than in the original unsmoothed maps, with relatively high coverage in urban areas than in rural areas for all indicators. The percentage of households possessing at least one bednet was 19% (95% credible interval (CI): 16-21%), with 9% (95% CI: 7-11%) of children sleeping under a net, while 18% (95% CI: 16-19%) of households had retreated their nets within past 12 months prior to the survey. The northern region and lakeshore areas had high bednet coverage, but low usage and re-treatment rates. Coverage rate of children who received antimalarial treatment within 24 hours after onset of fever was consistently low for most parts of the country, with mean coverage of 4.8% (95% CI: 4.5-5.0%). About 48% (95% CI: 47-50%) of women received antimalarial prophylaxis during their pregnancy, with highest rates in the southern and northern areas. CONCLUSION: The striking geographical patterns, for example between predominantly urban and rural areas, may reflect spatial differences in provider compliance or coverage, and can partly be explained by socio-economic and cultural differences. The wide gap between high bed net coverage and low retreatment rates may reflect variation in perceptions about malaria, which may be addressed by implementing information, education and communication campaigns or introducing long lasting insecticide nets. Our results demonstrate that DHS data, with appropriate methodology, can provide acceptable estimates at sub-national level for monitoring and evaluation of malaria control goals
Primary health care delivery models in rural and remote Australia – a systematic review
© 2008 Wakerman et al; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background
One third of all Australians live outside of its major cities. Access to health services and health outcomes are generally poorer in rural and remote areas relative to metropolitan areas. In order to improve access to services, many new programs and models of service delivery have been trialled since the first National Rural Health Strategy in 1994. Inadequate evaluation of these initiatives has resulted in failure to garner knowledge, which would facilitate the establishment of evidence-based service models, sustain and systematise them over time and facilitate transfer of successful programs. This is the first study to systematically review the available published literature describing innovative models of comprehensive primary health care (PHC) in rural and remote Australia since the development of the first National Rural Health Strategy (1993–2006). The study aimed to describe what health service models were reported to work, where they worked and why.
Methods
A reference group of experts in rural health assisted in the development and implementation of the study. Peer-reviewed publications were identified from the relevant electronic databases. 'Grey' literature was identified pragmatically from works known to the researchers, reference lists and from relevant websites. Data were extracted and synthesised from papers meeting inclusion criteria.
Results
A total of 5391 abstracts were reviewed. Data were extracted finally from 76 'rural' and 17 'remote' papers. Synthesis of extracted data resulted in a typology of models with five broad groupings: discrete services, integrated services, comprehensive PHC, outreach models and virtual outreach models. Different model types assume prominence with increasing remoteness and decreasing population density. Whilst different models suit different locations, a number of 'environmental enablers' and 'essential service requirements' are common across all model types.
Conclusion
Synthesised data suggest that, moving away from Australian coastal population centres, sustainable models are able to address diseconomies of scale which result from large distances and small dispersed populations. Based on the service requirements and enablers derived from analysis of reported successful PHC service models, we have developed a conceptual framework that is particularly useful in underpinning the development of sustainable PHC models in rural and remote communities
Factors associated with the number of consultations per dietetic treatment: an observational study
Study of the doubly charmed tetraquark T+cc
Quantum chromodynamics, the theory of the strong force, describes interactions of coloured quarks and gluons and the formation of hadronic matter. Conventional hadronic matter consists of baryons and mesons made of three quarks and quark-antiquark pairs, respectively. Particles with an alternative quark content are known as exotic states. Here a study is reported of an exotic narrow state in the D0D0π+ mass spectrum just below the D*+D0 mass threshold produced in proton-proton collisions collected with the LHCb detector at the Large Hadron Collider. The state is consistent with the ground isoscalar T+cc tetraquark with a quark content of ccu⎯⎯⎯d⎯⎯⎯ and spin-parity quantum numbers JP = 1+. Study of the DD mass spectra disfavours interpretation of the resonance as the isovector state. The decay structure via intermediate off-shell D*+ mesons is consistent with the observed D0π+ mass distribution. To analyse the mass of the resonance and its coupling to the D*D system, a dedicated model is developed under the assumption of an isoscalar axial-vector T+cc state decaying to the D*D channel. Using this model, resonance parameters including the pole position, scattering length, effective range and compositeness are determined to reveal important information about the nature of the T+cc state. In addition, an unexpected dependence of the production rate on track multiplicity is observed
Not the opium of the people: Income and secularisation in a panel of Prussian counties 1886-1911
The authors construct a unique panel of income and Protestant church attendance for six waves of up to 175 Prussian counties spanning 1886-1911; to study the interplay between religion and the economy. In particular income levels and religious participation. Their unique database on historical church attendance stems from the practice of the Protestant Church in Germany to count the number of participations in Holy Communion every year, which Hölscher (2001) gathered at the church-district (Kirchenkreis) level from regional archives covering modern Germany. The Sacrament Statistics (Abendmahlsstatistik) stem from a uniform annual survey organized by the Statistical Central Office at the Protestant Higher Church Council in Berlin from 1880 (with precursors) to World War II. Data collection was done by the parish priests on a preprinted form following uniform surveying directives. Regional Consistories combined these parish data into registers at the level of church districts, which usually comprised 10-20 adjacent parishes. Their main indicator of church attendance is the number of participations in Holy Communion divided by the number of Protestants in a district. Our income data refer to the average annual income of male elementary-school teachers, available every five years from 1886 to 1911 for all Prussian counties (Kreise) from Education Censuses (Galloway (2007)). Their dataset covers an unbalanced panel of 175 territorial entities (“counties”) in 1886-1911. This sample of Prussian counties constitutes the intersection between end-of-19 -century Prussia (for which income data are available) and modern Germany (for which church attendance data are available) and is thus not necessarily representative of Prussia or of Germany. To this dataset, we merge cross-sectional data for Prussian counties used in Becker and Woessmann (2009)
Courses for teaching leadership capacity in professional engineering degrees in Australia and Europe
Recently many educational institutions across the globe have implemented engineering leadership programs either as a part of formal engineering curriculum or where leadership development is embedded into separate in-house programs. This shows a clear intent of these educational institutions to prepare their engineering students for solving the real world problems, recognizing that both technical and leadership skills are valuable for tomorrow’s engineers. Leadership programs in engineering education have been implemented in various formats with varying degrees of success. It has already been identified in research studies that 80-90% of the engineering leadership programs offered explicitly across the globe were based in the United States of America. However, in Europe and Australia, there is a noticeable lack of engineering leadership programs, particularly in undergraduate curriculum. In Australia, it has been identified that only two universities offered a comprehensive program that catered for engineering leadership and both of them were at the post-graduate level. There are other leadership initiatives undertaken by industry in Australia in collaboration with universities but non-explicit in nature. Similarly, Europe is not far ahead. Few engineering universities across the United Kingdom offer leadership programs either as comprehensive degree courses or in modular forms. In the rest of Europe, only Belgium offers a comprehensive explicit program at the postgraduate level. The programs which are offered across Australia and Europe have distinct design and delivery styles but there are certain key features which are common to most of the programs including professional partnerships, mentoring, engineering design and project-based approaches
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