4,176 research outputs found
Detecting the presence and concentration of nitrate in water using microwave spectroscopy
Nitrate is a common pollutant in surface waters which water companies must monitor for regulatory and safety reasons. The presence of nitrate in deionised water is detected and concentration estimated from microwave spectroscopy measurements in the range 9kHz-6GHz. Experimental results were obtained for 19 solutions (18 salt solutions in deionised water and 1 deionised water), each measured 10 times with 4001 points (total N=190). The resulting data was randomly assigned into equal parts training and test data (N=95 each). Both regression (for the estimation of nitrate concentration) and classification (for detecting the presence of nitrate) methods were considered, with a rigorous feature selection procedure used to identify two frequencies for each of the classification and regression problems. For detection classification models were applied with nitrate levels binned using 30mg/l as the threshold. A logistic regression model achieved AUROC of 0.9875 on test data and a multi-layer perceptron achieved AUROC of 0.9871. In each case the positive predictive value of the model could be optimised at 100% with sensitivity of 90% and specificity of 100%. For the concentration estimates, a linear regression model was able to explain 42% of the variance in the training data and 45% of the variance in the test data and an MLP model delivered similar performance, explaining 43% of variance in the training data and 47% of variance in the test data. A sensor based on this model would be appropriate for detecting the presence of nitrate above a given threshold but poor at estimating concentration
Secular trends in child and adult sexual violence--one decreasing and the other increasing: a population survey in Ireland.
BACKGROUND: Sexual violence is a worldwide problem affecting children and adults. Knowledge of trends in prevalence is essential to inform the design and evaluation of preventive and intervention programmes. We aimed to assess the prevalence of lifetime sexual violence for both sexes and to document the prevalence of adult and child abuse by birth year in the general population.
METHODS: National cluster-randomized telephone interview study of 3120 adults in Ireland was done.
RESULTS: Child sexual abuse involving physical contact was reported by 20% of women and 16% of men. In adulthood, figures were 20% and 10% for women and men, respectively. Prevalence of any form of sexual violence across the lifespan was 42% (women) and 38% (men). Analysis by year of birth indicated a curvilinear pattern for child sexual abuse with lower prevalence in the oldest and youngest participants. Sexual violence in young adulthood showed a linear pattern with higher prevalence in the youngest participants.
CONCLUSION: The trend of lower rates of experience of child sexual abuse in younger adults in the sample is in keeping with findings from other countries. The trend of higher rates of adult sexual violence in younger adults is worrying, particularly since the same participants reported less experience of child sexual abuse than the preceding generations. There is a paucity of international data addressing the issue of cohort differences in exposure to sexual violence. Within-study analysis, and follow-up studies designed to maximize replicability, are needed to inform discussion about societal trends in different types of sexual violence
Effect of enteric coating on antiplatelet activity of low-dose aspirin in healthy volunteers.
BACKGROUND AND PURPOSE: Aspirin resistance may be relatively common and associated with adverse outcome. Meta-analysis has clearly shown that 75 mg plain aspirin is the lowest effective dose; however, it is not known whether the recent increased use of enteric-coated aspirin could account for aspirin resistance. This study was designed to determine whether enteric-coated aspirin is as effective as plain aspirin in healthy volunteers. METHODS: Seventy-one healthy volunteers were enrolled in 3 separate bioequivalence studies. Using a crossover design, each volunteer took 2 different aspirin preparations. Five aspirin preparations were evaluated, 3 different enteric-coated 75-mg aspirins, dispersible aspirin 75 mg and asasantin (25-mg standard release aspirin plus 200-mg modified-release dipyridamole given twice daily). Serum thromboxane (TX) B2 levels and arachidonic acid-induced platelet aggregation were measured before and after 14 days of treatment. RESULTS: All other aspirin preparations tested were inferior to dispersible aspirin (P99%) inhibition (
Chlamydia Screening in Ireland: a pilot study of opportunistic screening for genital Chlamydia trachomatis infection in Ireland (2007-2009). Summary Integrated Report
Genital Chlamydia trachomatis (CT) infection is the most common curable, bacterial sexually transmitted infection (STI) worldwide [1, 2]. The number of cases notified in Ireland increased from 3,353 in 2005 to 5,781 in 2009 [3]. Notifications have increased since 2004 when legislation requiring laboratory notification came into effect. Chlamydia is usually a ‘silent’ asymptomatic infection, spread without the knowledge of those transmitting and contracting it: most cases remain undetected and thus untreated. It is a major public health problem because it causes pelvic inflammatory disease (PID) in up to 30% of infected women who are not treated, which can lead to ectopic pregnancy and tubal factor infertility, and it also facilitates the transmission of HIV in both women and men [1, 4].
Prevalence studies in Ireland have detected chlamydia in 4–11% of young people [5, 6, 7], with positivity rates of over 10% in some settings [8]. Similar rates have been found in large studies in the United Kingdom (UK) [9], elsewhere in Europe [10] and North America [11]. A 2004 review estimated UK rates of 4–5% for women under 20 years in the general population, and 8–17% in women under 20 years attending sexual health services [9]. The authors of the review assumed, in the absence of data, that males had similar rates. Age under 25 years is considered a risk factor for infection in England [12]. In the English National Chlamydia Screening Programme (NCSP) overall chlamydia positivity rates have averaged 7.6% in men and 9.3% in women, based on a total of 370,012 screening tests reported [13].
Chlamydia screening has become more feasible due to the development of urinebased laboratory tests, which can be used in clinical and non-clinical settings, instead of more invasive and uncomfortable methods such as endocervical and urethral swabs. Urine testing is now the norm for screening men for chlamydia. For these reasons and because most cases are asymptomatic and undetected, especially in women, several countries have introduced chlamydia screening interventions [1].
A 2005 report prepared by the Health Protection Surveillance Centre (HPSC) [14] concluded that an investigation of the feasibility, acceptability and likely uptake of chlamydia screening in various settings in Ireland should be prioritised. It also concluded that agreement on best practice for the management of identified infections and partner notification was urgently needed. Following a competitive tendering process in late 2006, the HPSC, supported by the Health Research Board (HRB), contracted a team of population health and other specialists from the Royal College of Surgeons in Ireland (RCSI), the National University of Ireland Galway (NUIG) and the Health Service Executive (HSE) to conduct a pilot study of chlamydia screening.The study ran from 2007 to 2009.
Since 2009, several articles and reports have been published internationally, including reviews and the results of screening studies, which question the case for chlamydia screening in the general population. A systematic review of screening programmes concluded that the available evidence did not justify the establishment of opportunistic chlamydia screening programmes in under-25 year olds in the general population, given methodological weaknesses in the trials cited as justification for screening [4].
A review of the three phases of the English National Chlamydia Screening Programme (NCSP) reported screening coverage levels in the target population of only 4.8% in 2007–2008 [13]; although by 2009–2010, 47% of sexually active young women and 25% of men had been tested [15]. A review by the English National Audit Office [16] concluded that the NCSP had not demonstrated value for money, citing lack of efficiencies in purchasing and logistics. Also, models had shown that annual testing rates of young people of between 26% and 43% would be needed in order to significantly reduce the prevalence of chlamydia [17]. The recent higher coverage levels achieved by the NCSP in reaching these recommended levels is a cause for optimism, and valuable lessons will be learned from the English national programme.
However, the potential of opportunistic chlamydia screening to prevent serious morbidity (chiefly pelvic inflammatory disease in women) has been challenged by the results of an important randomised control trial of screening among young female students in London [18]. The trial found that most episodes of PID (30 of 38) would not have been prevented by annual screening as they occurred in women who had tested negative for chlamydia at the start of the 12 months
Chlamydia Screening in Ireland: a pilot study of opportunistic screening for genital Chlamydia trachomatis infection in Ireland (2007-2009). Screening Intervention Report
This report summarises the findings of the Pilot Screening Intervention conducted in Ireland between 2008 and 2009 as part of the Chlamydia Screening in Ireland Pilot study. The studies aimed to pilot screening models and to evaluate their feasibility and effectiveness.
The study was commissioned by the Health Protection Surveillance Centre (HPSC) and overseen by the Health Research Board (HRB). It was carried out by a team from the Division of Population Health Sciences at the Royal College of Surgeons (RSCI) in Ireland, the College of Medicine, Nursing and Health Sciences at the National University of Ireland Galway, and Consultants in Public Health Medicine from the Health Service Executive (HSE). ² Ethical approval for study components was provided by Research Ethics Committees of the RCSI, NUI Galway and the Irish College of General Practitioners (ICGP)
Perfectionism and achievement goals in young Finnish ice-hockey players aspiring to make the Under-16 national team
Research on perfectionism suggests that is it useful to differentiate between perfectionistic strivings and perfectionistic concerns. Regarding the 2 x 2 achievement goal framework, the usefulness of this differentiation was recently demonstrated in a study with university student athletes (Stoeber, Stoll, Pescheck, & Otto, 2008, Study 2), in which it was found that perfectionistic strivings were associated with mastery-approach and performance-approach goals and perfectionistic concerns with mastery-avoidance, performance-approach, and performance-avoidance goals. Because the study was largely exploratory and only used non-elite athletes, the aim of the present research was to replicate and extend these findings by investigating a sample of 138 young, elite ice-hockey players, while adding further measures of perfectionism and using structural equation modelling (SEM) to confirm the relationships between perfectionistic strivings, perfectionistic concerns,and the 2 x 2 achievement goals. The SEM results showed that, in elite athletes also, perfectionistic strivings are associated with mastery-approach and performance-approach goals, whereas perfectionistic concerns are associated with masteryavoidance,
performance-approach, and performance-avoidance goals. Our findings corroborate the importance of differentiating between perfectionistic strivings and perfectionistic concerns when studying perfectionism in sports, because
only perfectionistic concerns (and not perfectionistic strivings) are associated with maladaptive patterns of achievement goals
- …
