614 research outputs found

    Superfluid Helium Tanker (SFHT) study

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    Replenishment of superfluid helium (SFHe) offers the potential of extending the on-orbit life of observatories, satellite instruments, sensors and laboratories which operate in the 2 K temperature regime. A reference set of resupply customers was identified as representing realistic helium servicing requirements and interfaces for the first 10 years of superfluid helium tanker (SFHT) operations. These included the Space Infrared Telescope Facility (SIRTF), the Advanced X-ray Astrophysics Facility (AXAF), the Particle Astrophysics Magnet Facility (Astromag), and the Microgravity and Materials Processing Sciences Facility (MMPS)/Critical Point Phenomena Facility (CPPF). A mixed-fleet approach to SFHT utilization was considered. The tanker permits servicing from the Shuttle cargo bay, in situ when attached to the OMV and carried to the user spacecraft, and as a depot at the Space Station. A SFHT Dewar ground servicing concept was developed which uses a dedicated ground cooling heat exchanger to convert all the liquid, after initial fill as normal fluid, to superfluid for launch. This concept permits the tanker to be filled to a near full condition, and then cooled without any loss of fluid. The final load condition can be saturated superfluid with any desired ullage volume, or the tank can be totally filed and pressurized. The SFHT Dewar and helium plumbing system design has sufficient component redundancy to meet fail-operational, fail-safe requirements, and is designed structurally to meet a 50 mission life usage requirement. Technology development recommendations were made for the selected SFHT concept, and a Program Plan and cost estimate prepared for a phase C/D program spanning 72 months from initiation through first launch in 1997

    The Wow Factor? A Comparative Study of the Development of Student Music Teachers' Talents in Scotland and Australia

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    For some time there has been debate about differing perspectives on musical gift and musical intelligence. One view is that musical gift is innate: that it is present in certain individuals from birth and that the task of the teacher is to develop the potential which is there. A second view is that musical gift is a complex concept which includes responses from individuals to different environments and communities (Howe and Sloboda, 1997). This then raises the possibility that musical excellence can be taught. We have already explored this idea with practising musicians (Stollery and McPhee, 2002). Our research has now expanded to include music teachers in formation, and, in this paper, we look at the influences in their musical development which have either 'crystallised' or 'paralysed' the musical talent which they possess. Our research has a comparative dimension, being carried out in Scotland and in Australia. We conclude that there are several key influences in the musical development of the individual, including home and community support, school opportunities and teaching styles and that there may be education and culture-specific elements to these influences

    Fournier gangrene with concurrent multifocal necrotizing fasciitis: a systematic review and case report

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    Purpose A patient presented to a regional surgical center with Fournier gangrene (FG) and concurrent multifocal necrotizing fasciitis (NF). Given the rarity, it was decided to undertake a systematic review to investigate the incidence and prevalence of FG with multifocal NF and consequently determine the treatment and approach to management of such presentation. Methods Firstly, the report of the 56-year-old male patient is discussed regarding his surgical management. Secondly, a systematic review was undertaken according to PRISMA guidelines using MEDLINE, Scopus, and Embase databases. Searches used the following MeSH terms: (“fournier’s gangrene”) AND ((necrotising fasciitis) OR (necrotising soft tissue infection)). Once the search results were obtained, duplicate articles were removed. Titles, abstracts, and articles were reviewed by 2 authors. Results The search strategy using the 3 databases revealed a total of 402 studies. Fifty-seven studies were removed due to duplication. A total of 345 records were screened via title and abstract, of which 115 were excluded. Two hundred and thirty studies were reviewed for eligibility. A total of all 230 studies were excluded; 169 were excluded as they included the incorrect patient population (patients suffered from FG or NF, but not both collectively), 60 studies were excluded due to incorrect study designs, and 1 report occurred in the wrong setting. Conclusion This highlights that while being a relatively known, uncommon infection both FG and NF are well documented separately within the literature. However, FG with concurrent multifocal NF has not been documented within the literature

    Diet patterns and dental caries in third grade U. S. children

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    The purpose of this study was to investigate further the relationship between intake of sucrose-containing foods and the prevalence of caries in a natural population of children. The study population was made up of 958 Caucasian third grade children from Minneapolis. Diet and brushing information was collected through personal interviews with the children. Four methods of coding diet information were used: (1) Confection Counting (the number of sucrose-containing items consumed during a 24-hour period); (2) Exposure Counting (to collapse sucrose-containing items consumed in a 30-min interval into one sucrose exposure); (3) Minneapolis Oral Retention Estimate (an assessment of usual consumption, 24-hour recall, brushing and consumption of water to estimate likelihood that the individual had sucrose in the oral cavity during a typical day); and (4) Hidden Sugar Estimate (utilization of food composition tables to estimate in teaspoons how much sucrose was consumed during a 24-hour period). The study shows few, if any, relationships existing between consumption of sucrose-containing foods and def or DMF teeth in both mealtime and between-meal periods.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72430/1/j.1600-0528.1974.tb01653.x-i1.pd

    Changing Attitudes Towards Condoms Among Australian Gay and Bisexual Men in the PrEP Era: An Analysis of Repeated National Online Surveys 2011-2019

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    Condoms have been the primary form of HIV prevention for gay and bisexual men (GBM) for most of the HIV epidemic. The introduction of biomedical HIV prevention may have changed attitudes towards condoms. Data from repeated national online surveys of GBM in Australia were used to examine how attitudes towards condoms and confidence discussing condoms with partners changed in the period 2011-2019. The proportion of all participants who reported a positive experience in using condoms remained low and unchanged (9.6% in 2011 to 6.0% in 2019). Confidence in discussing condoms with partners decreased over time (from 72.2% in 2011 to 56.6% in 2019). Confidence in discussing condoms was associated with concern about sexually transmitted infections, and more consistent condom use. Sustaining confidence in using condoms may be more challenging as biomedical prevention methods become more commonly used

    Sunshine, rainfall, humidity and child pneumonia in the tropics: time-series analyses

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    Few studies have formally examined the relationship between meteorological factors and the incidence of child pneumonia in the tropics, despite the fact that most child pneumonia deaths occur there. We examined the association between four meteorological exposures (rainy days, sunshine, relative humidity, temperature) and the incidence of clinical pneumonia in young children in the Philippines using three time-series methods: correlation of seasonal patterns, distributed lag regression, and case-crossover. Lack of sunshine was most strongly associated with pneumonia in both lagged regression [overall relative risk over the following 60 days for a 1-h increase in sunshine per day was 0·67 (95% confidence interval (CI) 0·51–0·87)] and case-crossover analysis [odds ratio for a 1-h increase in mean daily sunshine 8–14 days earlier was 0·95 (95% CI 0·91–1·00)]. This association is well known in temperate settings but has not been noted previously in the tropics. Further research to assess causality is needed

    Paired Comparison of Observed and Expected Coronary Heart Disease Rates over 12 Years from the Atherosclerosis Risk In Communities Study

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    To quantify the relationship between coronary heart disease (CHD) risk factor levels and changes over time and population-wide CHD morbidity and mortality

    Estimating treatment effects for individual patients based on the results of randomised clinical trials

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    Objectives To predict treatment effects for individual patients based on data from randomised trials, taking rosuvastatin treatment in the primary prevention of cardiovascular disease as an example, and to evaluate the net benefit of making treatment decisions for individual patients based on a predicted absolute treatment effect

    The sense and nonsense of direct-to-consumer genetic testing for cardiovascular disease

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    Expectations are high that increasing knowledge of the genetic basis of cardiovascular disease will eventually lead to personalised medicine—to preventive and therapeutic interventions that are targeted to at-risk individuals on the basis of their genetic profiles. Most cardiovascular diseases are caused by a complex interplay of many genetic variants interacting with many non-genetic risk factors such as diet, exercise, smoking and alcohol consumption. Since several years, genetic susceptibility testing for cardiovascular diseases is being offered via the internet directly to consumers. We discuss five reasons why these tests are not useful, namely: (1) the predictive ability is still limited; (2) the risk models used by the companies are based on assumptions that have not been verified; (3) the predicted risks keep changing when new variants are discovered and added to the test; (4) the tests do not consider non-genetic factors in the prediction of cardiovascular disease risk; and (5) the test results will not change recommendations of preventive interventions. Predictive genetic testing for multifactorial forms of cardiovascular disease clearly lacks benefits for the public. Prevention of disease should therefore remain focused on family history and on non-genetic risk factors as diet and physical activity that can have the strongest impact on disease risk, regardless of genetic susceptibility
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