6,711 research outputs found

    Investigation of critical burning of fuel droplets

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    Fuel droplets were simulated by porous spheres having diameters in the range 0.63 to 1.9 cm and combustion tests were conducted at pressures up to 78 atm in a quiescent cold air environment. Measurements were made of the burning rate and liquid surface temperature during steady combustion. A high pressure flat flame burner apparatus is under development in order to allow testing of high pressure droplet burning in a combustion gas environment. Work was continued on the high pressure strand combustion characteristics of liquid fuels, with the major emphasis on hydrazine. Data was obtained on the burning rate and liquid surface temperatures at pressures in the range 7 to 500 psia. The response of a burning liquid monopropellant to imposed pressure oscillations is being investigated

    Factors associated with not seeking professional help or disclosing intent prior to suicide : A study of medical examiners' records in Nova Scotia

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    Individual-level data from clinical settings lack information on people who did not seek professional help prior to suicide. We used records of the Nova Scotia Medical Examiner Service (NSMES) to compare people who had contact with a health professional prior to suicide with those who did not.We linked data from the NSMES to routine administrative data of the province.The NSMES recorded 108 suicides in Nova Scotia from January 1, 2006, to December 31, 2006; there were 90 male and 18 female suicide deaths. Mean and median age at death were 44.73 (SD 13.33) and 44 years, respectively. Patients aged 40 to 49 years made up one-third of the cases (n = 35) and this was the decade of life with the highest number of suicides. This was also the group least likely to have suicidal intent recorded in the NSMES files (χ(2) = 3.86, df = 1, P = 0.05). Otherwise, there were no significant differences between people who sought help, or disclosed intent, prior to suicide and people who did not. The samples in all cases were predominately male and single.People aged 40 to 49 years were the age group with the highest absolute number of suicides, but were the least likely to have suicidal intent recorded in the NSMES files. This finding merits further investigation. Medical examiner or coroner data may provide additional information not obtained elsewhere for the surveillance of suicide

    The investigation of critical pressure burning of fuel droplets Annual report, 1 Jan. - 31 Dec. 1970

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    Experimental and theoretical results of critical pressure burning of fuel droplet

    High pressure combustion of liquid fuels

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    Measurements were made of the burning rates and liquid surface temperatures for a number of alcohol and n-paraffin fuels under natural and forced convection conditions. Porous spheres ranging in size from 0.64-1.9 cm O.D. were emloyed to simulate the fuel droplets. The natural convection cold gas tests considered the combustion in air of methanol, ethanol, propanol-1, n-pentane, n-heptane, and n-decane droplets at pressures up to 78 atmospheres. The pressure levels of the natural convection tests were high enough so that near critical combustion was observed for methanol and ethanol vaporization rates and liquid surface temperature measurements were made of droplets burning in a simulated combustion chamber environment. Ambient oxygen molar concentrations included 13%, 9.5% and pure evaporation. Fuels used in the forced convection atmospheric tests included those listed above for the natural convection tests. The ambient gas temperature ranged from 600 to 1500 K and the Reynolds number varied from 30 to 300. The high pressure forced convection tests employed ethanol and n-heptane as fuels over a pressure range of one to 40 atmospheres. The ambient gas temperature was 1145 K for the two combustion cases and 1255 K for the evaporation case

    On the calibration of the relation between geometric albedo and polarimetric properties for the asteroids

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    We present a new extensive analysis of the old problem of finding a satisfactory calibration of the relation between the geometric albedo and some measurable polarization properties of the asteroids. To achieve our goals, we use all polarimetric data at our disposal. For the purposes of calibration, we use a limited sample of objects for which we can be confident to know the albedo with good accuracy, according to previous investigations of other authors. We find a new set of updated calibration coefficients for the classical slope - albedo relation, but we generalize our analysis and we consider also alternative possibilities, including the use of other polarimetric parameters, one being proposed here for the first time, and the possibility to exclude from best-fit analyzes the asteroids having low albedos. We also consider a possible parabolic fit of the whole set of data.Comment: Accepted by MNRA

    How Equity-Oriented Health Care Affects Health: Key Mechanisms and Implications for Primary Health Care Practice and Policy

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    Policy Points A consensus regarding the need to orient health systems to address inequities is emerging, with much of this discussion targeting population health interventions and indicators. We know less about applying these approaches to primary health care. This study empirically demonstrates that providing more equity-oriented health care (EOHC) in primary health care, including trauma- and violence-informed, culturally safe, and contextually tailored care, predicts improved health outcomes across time for people living in marginalizing conditions. This is achieved by enhancing patients’ comfort and confidence in their care and their own confidence in preventing and managing health problems. This promising new evidence suggests that equity-oriented interventions at the point of care can begin to shift inequities in health outcomes for those with the greatest need. Context: Significant attention has been directed toward addressing health inequities at the population health and systems levels, yet little progress has been made in identifying approaches to reduce health inequities through clinical care, particularly in a primary health care context. Although the provision of equity-oriented health care (EOHC) is widely assumed to lead to improvements in patients’ health outcomes, little empirical evidence supports this claim. To remedy this, we tested whether more EOHC predicts more positive patient health outcomes and identified selected mediators of this relationship. Methods: Our analysis uses longitudinal data from 395 patients recruited from 4 primary health care clinics serving people living in marginalizing conditions. The participants completed 4 structured interviews composed of self-report measures and survey questions over a 2-year period. Using path analysis techniques, we tested a hypothesized model of the process through which patients’ perceptions of EOHC led to improvements in self-reported health outcomes (quality of life, chronic pain disability, and posttraumatic stress [PTSD] and depressive symptoms), including particular covariates of health outcomes (age, gender, financial strain, experiences of discrimination). Findings: Over a 24-month period, higher levels of EOHC predicted greater patient comfort and confidence in the health care patients received, leading to increased confidence to prevent and manage their health problems, which, in turn, improved health outcomes (depressive symptoms, PTSD symptoms, chronic pain, and quality of life). In addition, financial strain and experiences of discrimination had significant negative effects on all health outcomes. Conclusions: This study is among the first to demonstrate empirically that providing more EOHC predicts better patient health outcomes over time. At a policy level, this research supports investments in equity-focused organizational and provider-level processes in primary health care as a means of improving patients’ health, particularly for those living in marginalizing conditions. Whether these results are robust in different patient groups and across a broader range of health care contexts requires further study

    The epidemiology of travel-related Salmonella Enteritidis in Ontario, Canada, 2010–2011

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    <p>Abstract</p> <p>Background</p> <p>Increases in the number of salmonellosis cases due to <it>Salmonella</it> Enteritidis (SE) in 2010 and 2011 prompted a public health investigation in Ontario, Canada. In this report, we describe the current epidemiology of travel-related (TR) SE, compare demographics, symptoms and phage types (PTs) of TR and domestically-acquired (DA) cases, and estimate the odds of acquiring SE by region of the world visited.</p> <p>Methods</p> <p>All incident cases of culture confirmed SE in Ontario obtained from isolates and specimens submitted to public health laboratories were included in this study. Demographic and illness characteristics of TR and DA cases were compared. A national travel survey was used to provide estimates for the number of travellers to various destinations to approximate rates of SE in travellers. Multivariate logistic regression was used to estimate the odds of acquiring SE when travelling to various world regions.</p> <p>Results</p> <p>Overall, 51.9% of SE cases were TR during the study period. This ranged from 35.7% TR cases in the summer travel period to 65.1% TR cases in the winter travel period. Compared to DA cases, TR cases were older and were less likely to seek hospital care. For Ontario travellers, the adjusted odds of acquiring SE was the highest for the Caribbean (OR 37.29, 95% CI 17.87-77.82) when compared to Europe. Certain PTs were more commonly associated with travel (e.g., 1, 4, 5b, 7a, Atypical) than with domestic infection. Of the TR cases, 88.9% were associated with travel to the Caribbean and Mexico region, of whom 90.1% reported staying on a resort. Within this region, there were distinct associations between PTs and countries.</p> <p>Conclusions</p> <p>There is a large burden of TR illness from SE in Ontario. Accurate classification of cases by travel history is important to better understand the source of infections. The findings emphasize the need to make travellers, especially to the Caribbean, and health professionals who provide advice to travellers, aware of this risk. The findings may be generalized to other jurisdictions with travel behaviours in their residents similar to Ontario residents.</p

    The minimum energy expenditure shortest path method

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    This article discusses the addition of an energy parameter to the shortest path execution process; namely, the energy expenditure by a character during execution of the path. Given a simple environment in which a character has the ability to perform actions related to locomotion, such as walking and stair stepping, current techniques execute the shortest path based on the length of the extracted root trajectory. However, actual humans acting in constrained environments do not plan only according to shortest path criterion, they conceptually measure the path that minimizes the amount of energy expenditure. On this basis, it seems that virtual characters should also execute their paths according to the minimization of actual energy expenditure as well. In this article, a simple method that uses a formula for computing vanadium dioxide (VO2VO_2) levels, which is a proxy for the energy expenditure by humans during various activities, is presented. The presented solution could be beneficial in any situation requiring a sophisticated perspective of the path-execution process. Moreover, it can be implemented in almost every path-planning method that has the ability to measure stepping actions or other actions of a virtual character

    Aboriginal Children and Their Caregivers Living with Low Income: Outcomes from a Two-Generation Preschool Program

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    The development of preschool children of Aboriginal heritage is jeopardized by the inter-generational transmission of risk that has created, and continues to create, social disadvantage. Early intervention programs are intended to mitigate the impact of social disadvantage. Yet, evidence of the effectiveness of these programs for children of Aboriginal heritage is limited. The purpose of this study was to examine the effects of a two-generation, multi-cultural preschool program on 45 children of Aboriginal heritage and their caregivers. We used a single-group, pretest (program intake)/posttest (program exit) design with follow-up when the children were 7 years old. We used an observational measure of child receptive language (Peabody Picture Vocabulary Test–III) and caregiver-reported measures of child development (Nipissing District Developmental Screen), risk for child maltreatment (Adult-Adolescent Parenting Inventory; AAPI), parenting stress (Parenting Stress Index; PSI), self-esteem (Rosenberg Self-Esteem scale; RSE), and life skills (Community Life Skills scale; CLS). Using paired t-tests we found statistically significant increases in child receptive language scores between intake and exit, and repeated-measures ANOVA showed that these improvements were maintained up to age 7 years. For caregivers, Pearson’s correlations demonstrated that risk for child maltreatment, parenting stress, self-esteem, and life skills were stable over time. Results of this study suggest that children of Aboriginal heritage can benefit from participation in a two-generation, multi-cultural preschool program. Their caregivers may have received greater benefit if issues of intergenerational transmission of the negative influences of residential schools were addressed as part of programming
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