Computing binary black hole merger waveforms using openGR

textOne of the most important predictions of General Relativity, Einstein’s theory of gravity, is the existence of gravitational radiation. The strongest source of such radiation is expected to come from the merging of black holes. Upgrades to large ground based interferometric detectors (LIGO, VIRGO, GEO 600) have increased their sensitivity to the point that the first direct observation of a gravitational wave is expected to occur within the next few years. The chance of detection is greatly improved by the use of simulated waveforms which can be used as templates for signal processing. Recent advances in numerical relativity have allowed for long stable evolution of black hole mergers and the generation of expected waveforms. openGR is a modular, open framework black hole evolution code developed at The University of Texas at Austin Center for Relativity. Based on the BSSN (strongly hyperbolic) formulation of Einstein’s equations and the moving puncture method, we are able to model the evolution of a binary black hole system through the merger and extract the gravitational radiation produced. Although we are generally interested in binary interactions, openGR is capable of handling any number of black holes. This work serves as an overview of the capabilities of openGR and a demonstration of the physics it can be used to explore.Physic

Asbestos in Scotland

This paper outlines the asbestos hazard in Scotland and draws upon a systematic oral history project to analyze from the workers’ perspective the nature of exposure, the limitations of government regulatory initiatives, and the ramifications of contracting asbestos-related diseases for sufferers and their families. Current issues are investigated, stressing the agency of workers, trade unions, sympathetic local councils, and, especially, the victims’ pressure groups. The occupational and environmental health threats of asbestos in Scotland remain significant, although recent E.U.- and U.K.- based decisions to ban further use of asbestos together with active campaigning by local activist groups have helped to reduce them. Mesothelioma mortality rates remain high, due to historic exposures, and much work remains to be done to reduce the number and plight of asbestos-exposed workers. Key words: asbestos; mesothelioma; Scotland; Clydeside

More haste, less speed? : an evaluation of fast track policies to tackle persistent youth offending in Scotland

In 2003 the Scottish Executive introduced a new 'Fast Track' policy on a pilot basis, which was intended to speed up the processing of persistent youth offending cases and reduce rates of persistent offending. Additional resources were provided to promote access to dedicated programmes, as well as quicker assessment, report delivery and decision making. This paper, based on a multi-stranded comparative evaluation, describes how the policy was welcomed by a wide range of practitioners, decision makers and managers involved with children's hearings who mostly thought it was a positive innovation consistent with the hearing system's commitment to a welfare-based approach. 'Fast Track' cases were handled more quickly than others. After two years, however, the policy was discontinued, largely because of negative evidence about re-offending

Effect of smoking on lung function, respiratory symptoms and respiratory diseases amongst HIV-positive subjects: a cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Smoking prevalence in human immunodeficiency virus (HIV) positive subjects is about three times of that in the general population. However, whether the extremely high smoking prevalence in HIV-positive subjects affects their lung function is unclear, particularly whether smoking decreases lung function more in HIV-positive subjects, compared to the general population. We conducted this study to determine the association between smoking and lung function, respiratory symptoms and diseases amongst HIV-positive subjects.</p> <p>Results</p> <p>Of 120 enrolled HIV-positive subjects, 119 had an acceptable spirogram. Ninety-four (79%) subjects were men, and 96 (81%) were white. Mean (standard deviation [SD]) age was 43.4 (8.4) years. Mean (SD) of forced expiratory volume in one second (FEV₁) percent of age, gender, race and height predicted value (%FEV₁) was 93.1% (15.7%). Seventy-five (63%) subjects had smoked 24.0 (18.0) pack-years. For every ten pack-years of smoking increment, %FEV₁decreased by 2.1% (95% confidence interval [CI]: -3.6%, -0.6%), after controlling for gender, race and restrictive lung function (R²= 0.210). The loss of %FEV₁in our subjects was comparable to the general population. Compared to non-smokers, current smokers had higher odds of cough, sputum or breathlessness, after adjusting for highly active anti-retroviral therapy (HAART) use, odds ratio OR = 4.9 (95% CI: 2.0, 11.8). However respiratory symptom presence was similar between non-smokers and former smokers, OR = 1.0 (95% CI: 0.3, 2.8). All four cases of COPD (chronic obstructive pulmonary disease) had smoked. Four of ten cases of restrictive lung disease had smoked (p = 0.170), and three of five asthmatic subjects had smoked (p = 1.000).</p> <p>Conclusions</p> <p>Cumulative cigarette consumption was associated with worse lung function; however the loss of %FEV₁did not accelerate in HIV-positive population compared to the general population. Current smokers had higher odds of respiratory symptoms than non-smokers, while former smokers had the same odds of respiratory symptoms as non-smokers. Cigarette consumption was likely associated with more COPD cases in HIV-positive population; however more participants and longer follow up would be needed to estimate the effect of smoking on COPD development. Effective smoking cessation strategies are required for HIV-positive subjects.</p

The outcomes of secure care in Scotland

This paper describes the findings of a three year study of the use and effectiveness of secure accommodation in Scotland. Data were collected on 53 young people shortly after their admission to secure accommodation. Most young people were admitted because they were a danger to themselves and/or they were likely to abscond; a third were considered a danger to others. Secure accommodation was considered to have benefits in relation to keeping young people safe and addressing health issues. On other dimensions, such as behaviour or family relationships, signs of benefit were more ambiguous. Thirty-three young people were considered to have clearly benefited from placement. At follow-up, after two years, outcomes were assessed as: 'good' - 14 (26%); 'medium'- 24 (45 %); and 'poor' - 15 (28%). The research highlighted the importance of effectively managing the transition from secure care. Social workers attributed a good outcome more to an appropriate placement and education being offered when the young person left secure rather than simply the placement itself. A gradual 'step-down' approach from the structure and supervision of the secure setting was also linked to better outcomes. Young people respond well when offered continuity and the opportunity to develop relationships with one or more reliable adults who can help with problems as they arise

Secure Accommodation in Scotland: Its Role and Relationship with ‘Alternative’ Services - Summary

This research was carried out between November 2002 - 2005 to increase understanding of the use and effectiveness of secure accommodation in relation to young people placed on the authority of a children's hearing. It also examined the circumstances in which open residential or community-based services might provide an &lsquo;alternative' to secure placement

Balancing Pastoral and Plantation Forestry Options in New Zealand and the Role of Agroforestry

Pastoral agriculture and forestry enterprises are key features of New Zealand’s landscape and are very important economically. They are competing landuses, particularly on moderate to steep hill country. Agroforestry involving spaced trees of Pinus radiata on pasture was developed in the 1970s to provide dual incomes from livestock enterprises and the later tree crop. In contrast, wide-spaced trees of predominantly Populus and Salix spp. are planted mainly for erosion control. Characteristics of pastoralism and plantation forestry are reviewed, including trends in conversions between these landuses. Roles, challenges and opportunities with wide-spaced trees are presented, together with current and future research initiatives. Pastoralism and forestry will continue to compete strongly for hill country sites and at present there is an increasing trend of converting previously forested areas to pasture, particularly in the central North Island. Agroforestry involving Pinus radiata has virtually ceased because of adverse effects on wood quality, pasture production and animal performance. There are millions of wide-spaced trees of Populus and Salix spp. on hill country and their planting is expected to continue unabated because they are the most practical and efficient means of enabling pastoralism on erodible slopes and they provide multiple ecosystem services. The species have significant advantages compared to other woody species but many older trees have grown very large because they have received negligible or no silviculture. This is an increasing problem, requiring development and implementation of appropriate management strategies. There is growing interest by landowners in the environmental outcomes of spaced-tree plantings

Fast Track Children's Hearings Pilot : Final Report of the Evaluation of the Pilot

The Scottish Executive decided that a Fast Track approach to the children's hearings system would be introduced in early 2003 on a pilot basis in selected parts of Scotland. The aim was to improve practice and outcomes with respect to the ways that the hearings system and associated services dealt with young people who persistently offend. Particular objectives were to: • reduce the time taken both overall and at each stage of decision-making • promote more comprehensive assessments which include appraisals of offending risk • ensure that all young people who persistently offend and who require an appropriate programme have access to one • reduce re-offending rates as a result of the concerted efforts made in such cases

Boosting the productivity and profitability of northern Australian beef enterprises: Exploring innovation options using simulation modelling and systems analysis

The financial health of beef cattle enterprises in northern Australia has declined markedly over the last decade due to an escalation in production and marketing costs and a real decline in beef prices. Historically, gains in animal productivity have offset the effect of declining terms of trade on farm incomes. This raises the question of whether future productivity improvements can remain a key path for lifting enterprise profitability sufficient to ensure that the industry remains economically viable over the longer term. The key objective of this study was to assess the production and financial implications for north Australian beef enterprises of a range of technology interventions (development scenarios), including genetic gain in cattle, nutrient supplementation, and alteration of the feed base through introduced pastures and forage crops, across a variety of natural environments. To achieve this objective a beef systems model was developed that is capable of simulating livestock production at the enterprise level, including reproduction, growth and mortality, based on energy and protein supply from natural C4 pastures that are subject to high inter-annual climate variability. Comparisons between simulation outputs and enterprise performance data in three case study regions suggested that the simulation model (the Northern Australia Beef Systems Analyser) can adequately represent the performance beef cattle enterprises in northern Australia. Testing of a range of development scenarios suggested that the application of individual technologies can substantially lift productivity and profitability, especially where the entire feedbase was altered through legume augmentation. The simultaneous implementation of multiple technologies that provide benefits to different aspects of animal productivity resulted in the greatest increases in cattle productivity and enterprise profitability, with projected weaning rates increasing by 25%, liveweight gain by 40% and net profit by 150% above current baseline levels, although gains of this magnitude might not necessarily be realised in practice. While there were slight increases in total methane output from these development scenarios, the methane emissions per kg of beef produced were reduced by 20% in scenarios with higher productivity gain. Combinations of technologies or innovative practices applied in a systematic and integrated fashion thus offer scope for providing the productivity and profitability gains necessary to maintain viable beef enterprises in northern Australia into the future

Boosting the productivity and profitability of northern Australian beef enterprises: Exploring innovation options using simulation modelling and systems analysis

The financial health of beef cattle enterprises in northern Australia has declined markedly over the last decade due to an escalation in production and marketing costs and a real decline in beef prices. Historically, gains in animal productivity have offset the effect of declining terms of trade on farm incomes. This raises the question of whether future productivity improvements can remain a key path for lifting enterprise profitability sufficient to ensure that the industry remains economically viable over the longer term. The key objective of this study was to assess the production and financial implications for north Australian beef enterprises of a range of technology interventions (development scenarios), including genetic gain in cattle, nutrient supplementation, and alteration of the feed base through introduced pastures and forage crops, across a variety of natural environments. To achieve this objective a beef systems model was developed that is capable of simulating livestock production at the enterprise level, including reproduction, growth and mortality, based on energy and protein supply from natural C4 pastures that are subject to high inter-annual climate variability. Comparisons between simulation outputs and enterprise performance data in three case study regions suggested that the simulation model (the Northern Australia Beef Systems Analyser) can adequately represent the performance beef cattle enterprises in northern Australia. Testing of a range of development scenarios suggested that the application of individual technologies can substantially lift productivity and profitability, especially where the entire feedbase was altered through legume augmentation. The simultaneous implementation of multiple technologies that provide benefits to different aspects of animal productivity resulted in the greatest increases in cattle productivity and enterprise profitability, with projected weaning rates increasing by 25%, liveweight gain by 40% and net profit by 150% above current baseline levels, although gains of this magnitude might not necessarily be realised in practice. While there were slight increases in total methane output from these development scenarios, the methane emissions per kg of beef produced were reduced by 20% in scenarios with higher productivity gain. Combinations of technologies or innovative practices applied in a systematic and integrated fashion thus offer scope for providing the productivity and profitability gains necessary to maintain viable beef enterprises in northern Australia into the future