Assessing the Impact of Sensor Accuracy and Sensor Choice on Air Traffic Conflict Risk Estimation using Risk-Ratio Concepts

One of the primary desired capabilities of any future air traffic separation management system is the ability to provide early conflict detection and resolution effectively and efficiently. In this paper, we consider the risk of conflict as a primary measurement to be used for early conflict detection. This paper focuses on developing a novel approach to assess the impact of different measurement uncertainty models on the estimated risk of conflict. The measurement uncertainty model can be used to represent different sensor accuracy and sensor choices. Our study demonstrates the value of modelling measurement uncertainty in the conflict risk estimation problem and presents techniques providing a means of assessing sensor requirements to achieve desired conflict detection performance.

Pressure ulcers in the adult intensive care unit : a literature review of patient risk factors and risk assessment scales

Background: Critically ill patients are at high risk for pressure ulcer (PrU) development due to their high acuity and the invasive nature of the multiple interventions and therapies they receive. With reported incidence rates of PrU development in the adult critical care population as high as 56%, the identification of patients at high risk of PrU development is essential. This paper will explore the association between PrU development and risk factors. It will also explore PrU development and the use of risk assessment scales for critically ill patients in adult intensive care units. Method: A literature search from 2000 to 2012 using the CINHAL, Cochrane Library, EBSCOHost, Medline (via EBSCOHost), PubMed, ProQuest and Google Scholar databases was conducted. Key words used were: pressure ulcer/s; pressure sore/s; decubitus ulcer/s; bed sore/s; critical care; intensive care; critical illness; prevalence; incidence; prevention; management; risk factor; risk assessment scale. Results: Nineteen articles were included in this review; eight studies addressing PrU risk factors, eight studies addressing risk assessment scales and three studies overlapping both. Results from the studies reviewed identified 28 intrinsic and extrinsic risk factors which may lead to PrU development. Development of a risk factor prediction model in this patient population, although beneficial, appears problematic due to many issues such as diverse diagnoses and subsequent patient needs. Additionally, several risk assessment instruments have been developed for early screening of patients at higher risk of developing PrU in the ICU. No existing risk assessment scales are valid for identification high risk critically ill patient,with the majority of scales potentially over-predicting patients at risk for PrU development. Conclusion: Research studies to inform the risk factors for potential pressure ulcer development are inconsistent. Additionally, there is no consistent or clear evidence which demonstrates any scale to better or more effective than another when used to identify the patients at risk for PrU development. Furthermore robust research is needed to identify the risk factors and develop valid scales for measuring the risk of PrU development in ICU.

Indoor aerosols : from personal exposure to risk assessment

Motivated by growing considerations of the scale, severity and risks associated with human exposure to indoor particulate matter, this work reviewed existing literature to: (i) identify state-of-the-art experimental techniques used for personal exposure assessment; (ii) compare exposure levels reported for domestic/school settings in different countries (excluding exposure to environmental tobacco smoke and particulate matter from biomass cooking in developing countries); (iii) assess the contribution of outdoor background vs indoor sources to personal exposure; and (iv) examine scientific understanding of the risks posed by personal exposure to indoor aerosols. Limited studies assessing integrated daily residential exposure to just one particle size fraction, ultrafine particles, show that the contribution of indoor sources ranged from 19-76%. This indicates a strong dependence on resident activities, source events and site specificity, and highlights the importance of indoor sources for total personal exposure. Further, it was assessed that 10-30% of the total burden-of-disease from particulate matter exposure was due to indoor generated particles, signifying that indoor environments are likely to be a dominant environmental factor affecting human health. However, due to challenges associated with conducting epidemiological assessments, the role of indoor generated particles has not been fully acknowledged, and improved exposure/risk assessment methods are still needed, together with a serious focus on exposure control.

Vitamin D status and skin cancer risk independent of time outdoors : 11-year prospective study in and Australian community

Vitamin D may have anti-skin cancer effects, but population-based evidence is lacking. We therefore assessed associations between vitamin D status and skin cancer risk in an Australian subtropical community. We analyzed prospective skin cancer incidence for 11 years following baseline assessment of serum 25(OH)-vitamin D in 1,191 adults (average age 54 years) and used multivariable logistic regression analysis to adjust risk estimates for age, sex, detailed assessments of usual time spent outdoors, phenotypic characteristics, and other possible confounders. Participants with serum 25(OH)-vitamin D concentrations above 75 nmol  l(-1) versus those below 75 nmol  l(-1) more often developed basal cell carcinoma (odds ratio (OR)=1.51 (95% confidence interval (CI): 1.10-2.07, P=0.01) and melanoma (OR=2.71 (95% CI: 0.98-7.48, P=0.05)). Squamous cell carcinoma incidence tended to be lower in persons with serum 25(OH)-vitamin D concentrations above 75 nmol  l(-1) compared with those below 75 nmol  l(-1) (OR=0.67 (95% CI: 0.44-1.03, P=0.07)). Vitamin D status was not associated with skin cancer incidence when participants were classified as above or below 50 nmol  l(-1) 25(OH)-vitamin D. Our findings do not indicate that the carcinogenicity of high sun exposure can be counteracted by high vitamin D status. High sun exposure is to be avoided as a means to achieve high vitamin D status.

A 250 μg/week dose of vitamin D was as effective as a 50 μg/d dose in healthy adults, but a regimen of four weekly followed by monthly doses of 1250 μg raised the risk of hypercalciuria

The risk of vitamin D insufficiency is increased in persons having limited sunlight exposure and dietary vitamin D. Supplementation compliance might be improved with larger doses taken less often, but this may increase the potential for side effects. The objective of the present study was to determine whether a weekly or weekly/monthly regimen of vitamin D supplementation is as effective as daily supplementation without increasing the risk of side effects. Participants were forty-eight healthy adults who were randomly assigned for 3 months to placebo or one of three supplementation regimens: 50 μg/d (2000 IU/d, analysed dose 70 μg/d), 250 μg/week (10 000 IU/week, analysed dose 331 μg/week) or 1250 μg/week (50 000 IU/week, analysed dose 1544 μg/week) for 4 weeks and then 1250 μg/month for 2 months. Daily and weekly doses were equally effective at increasing serum 25-hydroxyvitamin D, which was significantly greater than baseline in all the supplemented groups after 30 d of treatment. Subjects in the 1250 μg treatment group, who had a BMI >26 kg/m2, had a steady increase in urinary Ca in the first 3 weeks of supplementation, and, overall, the relative risk of hypercalciuria was higher in the 1250 μg group than in the placebo group (P= 0·01). Although vitamin D supplementation remains a controversial issue, these data document that supplementing with ≤ 250 μg/week ( ≤ 10 000 IU/week) can improve or maintain vitamin D status in healthy populations without the risk of hypercalciuria, but 24 h urinary Ca excretion should be evaluated in healthy persons receiving vitamin D3 supplementation in weekly single doses of 1250 μg (50 000 IU).

Risk modelling in quality clinical registries : Monitoring lesion treatment failure rate in percutaneous coronary interventions

Aims: This paper describes the development of a risk adjustment (RA) model predictive of individual lesion treatment failure in percutaneous coronary interventions (PCI) for use in a quality monitoring and improvement program. Methods and results: Prospectively collected data for 3972 consecutive revascularisation procedures (5601 lesions) performed between January 2003 and September 2011 were studied. Data on procedures to September 2009 (n = 3100) were used to identify factors predictive of lesion treatment failure. Factors identified included lesion risk class (p < 0.001), occlusion type (p < 0.001), patient age (p = 0.001), vessel system (p < 0.04), vessel diameter (p < 0.001), unstable angina (p = 0.003) and presence of major cardiac risk factors (p = 0.01). A Bayesian RA model was built using these factors with predictive performance of the model tested on the remaining procedures (area under the receiver operating curve: 0.765, Hosmer–Lemeshow p value: 0.11). Cumulative sum, exponentially weighted moving average and funnel plots were constructed using the RA model and subjectively evaluated. Conclusion: A RA model was developed and applied to SPC monitoring for lesion failure in a PCI database. If linked to appropriate quality improvement governance response protocols, SPC using this RA tool might improve quality control and risk management by identifying variation in performance based on a comparison of observed and expected outcomes.

Brownfield re-development : Perceptions and risk mitigation strategies

Scarcity of large parcels of land in well-serviced areas has motivated people to re-develop brownfield land. Most of brownfield land has high risk of contamination from wide range of industrial activities such as gas works, factories, railway land and waste tips. In addition, people who live in brownfield re-development areas may be exposed to health hazards. This paper discusses public perceptions on the brownfield sites and also the risk and mitigation strategy to promote brownfield re-development. Data is gathered from face to face survey of fifty respondents who work in Brisbane Central Business District (CBD) and interview with an expert on remediation of contaminated land. From this preliminary study, it is found that majority of the population are not aware of any brownfield sites near their residence and those who are aware showed very little concern on their proximity to the site. Further discussion on the paper based on a simple cross tabulation analysis. The main risk mitigation strategy of re-development of brownfield site is by updating the registration through Environmental Management Register (EMR) and Contaminated Land Register (CLR). In addition, insurance may offer to cover cost overruns on remediation cost.

Corporate governance and risk management : the role of risk management and compensation committees

This paper examines the role of compensation and risk committees in managing and monitoring the risk behaviour of Australian financial firms in the period leading up to the global financial crisis (2006–2008). This empirical study of 711 observations of financial sector firms demonstrates how the coordination of risk management and compensation committees reduces information asymmetry. The study shows that the composition of the risk and compensation committees is positively associated with risk, which, in turn, is associated with firm performance. More importantly, information asymmetry is reduced when a director is a member of both the risk and compensation committees which moderate the negative association between risk and firm performance for firms with high risk.

Risk-taking, harm and help-seeking : reported by young people in treatment at a youth alcohol and drug counselling service

Regarded as a normative component of development, risk-taking by young people is a well-researched subject, and some risk-taking behaviours, such as substance use, are particularly well covered because of their potential to adversely affect health and wellbeing. What has remained unclear is the extent of young people's risk-taking while engaged in alcohol and other drug (AOD) treatment, their awareness of the related harms of risk-taking behaviours, and their prior help-seeking for these harms - information which may have a significant impact on the quality and relevance of the care they receive. This paper reports the findings from a brief pilot study exploring those factors in a clinical sample of young people engaged in ongoing AOD counselling.

Comparing cooperative and non-cooperative crash risk assessment

Cooperative Systems provide, through the multiplication of information sources over the road, a lot of potential to improve the assessment of the road risk describing a particular driving situation. In this paper, we compare the performance of a cooperative risk assessment approach against a non-cooperative approach; we used an advanced simulation framework, allowing for accurate and detailed, close-to-reality simulations. Risk is estimated, in both cases, with combinations of indicators based on the TTC. For the non-cooperative approach, vehicles are equipped only with an AAC-like forward-facing ranging sensor. On the other hand, for the cooperative approach, vehicles share information through 802.11p IVC and create an augmented map representing their environment; risk indicators are then extracted from this map. Our system shows that the cooperative risk assessment provides a systematic increase of forward warning to most of the vehicles involved in a freeway emergency braking scenario, compared to a non-cooperative system.

Coordinated probabilistic optimal decision-making model for multi-area ATC with risk control

In the decision-making of multi-area ATC (Available Transfer Capacity) in electricity market environment, the existing resources of transmission network should be optimally dispatched and coordinately employed on the premise that the secure system operation is maintained and risk associated is controllable. The non-sequential Monte Carlo simulation is used to determine the ATC probability density distribution of specified areas under the influence of several uncertainty factors, based on which, a coordinated probabilistic optimal decision-making model with the maximal risk benefit as its objective is developed for multi-area ATC. The NSGA-II is applied to calculate the ATC of each area, which considers the risk cost caused by relevant uncertainty factors and the synchronous coordination among areas. The essential characteristics of the developed model and the employed algorithm are illustrated by the example of IEEE 118-bus test system. Simulative result shows that, the risk of multi-area ATC decision-making is influenced by the uncertainties in power system operation and the relative importance degrees of different areas.

Comparison of moped, scooter and motorcycle crash risk and crash severity

The increased popularity of mopeds and motor scooters in Australia and elsewhere in the last decade has contributed substantially to the greater use of powered two-wheelers (PTWs) as a whole. As the exposure of mopeds and scooters has increased, so too has the number of reported crashes involving those PTW types, but there is currently little research comparing the safety of mopeds and, particularly, larger scooters with motorcycles. This study compared the crash risk and crash severity of motorcycles, mopeds and larger scooters in Queensland, Australia. Comprehensive data cleansing was undertaken to separate motorcycles, mopeds and larger scooters in police-reported crash data covering the five years to 30 June 2008. The crash rates of motorcycles (including larger scooters) and mopeds in terms of registered vehicles were similar over this period, although the moped crash rate showed a stronger downward trend. However, the crash rates in terms of distance travelled were nearly four times higher for mopeds than for motorcycles (including larger scooters). More comprehensive distance travelled data is needed to confirm these findings. The overall severity of moped and scooter crashes was significantly lower than motorcycle crashes but an ordered probit regression model showed that crash severity outcomes related to differences in crash characteristics and circumstances, rather than differences between PTW types per se. Greater motorcycle crash severity was associated with higher (>80 km/h) speed zones, horizontal curves, weekend, single vehicle and nighttime crashes. Moped crashes were more severe at night and in speed zones of 90 km/h or more. Larger scooter crashes were more severe in 70 km/h zones (than 60 km/h zones) but not in higher speed zones, and less severe on weekends than on weekdays. The findings can be used to inform potential crash and injury countermeasures tailored to users of different PTW types.

Narrative review of changing medical and feminist perspectives on menopause : from femininity and ageing to risk and choice

Meanings and descriptions of menopause have shifted focus over the past century and a half; more particularly the past sixty years has seen a shift from descriptions of hormone decline and its relation to ageing, femininity and symptoms of menopause since the 1960's to the possibility for preventive medicine afforded by menopause. Medicine is not a static field in its construction of menopause. It has changed, not least by its engagement (positively or negatively) with critique from both within (epidemiological) and without (feminist and social sciences). In this review we identify three recent changes: (1) Increasing concern with women's decision-making. (2) The emergence from within medicine of the rejection of the use of language which defines menopause as a condition of deficiency. (3) New insights from postmodern and poststructural analyses of menopause that examine the epistemological foundations of medical and feminist concepts of menopause and contest fixed descriptions of the experience of menopause. Key aspects of a ‘medical menopause’ nevertheless remain constant: menopause is a loss of hormones that results in predictable effects and risks and may be ameliorated by hormone replacement therapy. A question therefore emerges about how and to what effect medical practitioners have engaged with critiques of the medical menopause?

Menopause as a long-term risk to health : implications of general practitioner accounts of prevention for women’s choice and decision-making

Over the past two decades medical researchers and modernist feminist researchers have contested the meaning of menopause. In this article we examine various meanings of menopause in major medical and feminist literature and the construction of menopause in a semi-structured interview study of general practitioners in rural South Australia. Three discursive themes are identified in these interviews; (i) the hormonal menopause – symptoms, risk, prevention; (ii) the informed menopausal woman; and (iii) decision-making and hormone replacement therapy. By using the discourse of prevention, general practitioners construct menopause in relation to women's health care choices, empowerment and autonomy. We argue that the ways in which these concepts are deployed by general practitioners in this study produces and constrains the options available to women. The implications of these general practitioner accounts are discussed in relation to the proposition that medical and feminist descriptions of menopause posit alternative but equally-fixed truths about menopause and their relationship with the range of responses available to women at menopause. Social and cultural explanations of disease causality (c.f.Germov 1998, Hardey 1998) are absent from the new menopause despite their being an integral part of the framework of the women's health movement and health promotion drawn on by these general practitioners. Further, the shift of responsibility for health to the individual woman reinforces practice claims to empower women, but oversimplifies power relations and constructs menopause as a site of self-surveillance. The use of concepts from the women's health movement and health promotion have nevertheless created change in both the positioning of women as having ‘choices’ and the positioning of some general practitioners in terms of greater information provision to women and an attention to the woman's autonomy. In conclusion, we propose that a new menopause has evolved from a discursive shift in medicine and that there exists within this new configuration, claiming the empowerment of women as an integral part of health care for menopause, the possibility for change in medical practice which will broaden, strengthen, and maintain this position.