1,107 research outputs found

    Exponential sum approximations for t−βt^{-\beta}

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    Given β>0\beta>0 and δ>0\delta>0, the function t−βt^{-\beta} may be approximated for tt in a compact interval [δ,T][\delta,T] by a sum of terms of the form we−atwe^{-at}, with parameters w>0w>0 and a>0a>0. One such an approximation, studied by Beylkin and Monz\'on, is obtained by applying the trapezoidal rule to an integral representation of t−βt^{-\beta}, after which Prony's method is applied to reduce the number of terms in the sum with essentially no loss of accuracy. We review this method, and then describe a similar approach based on an alternative integral representation. The main difference is that the new approach achieves much better results before the application of Prony's method; after applying Prony's method the performance of both is much the same.Comment: 18 pages, 5 figures. I have completely rewritten this paper because after uploading the previous version I realised that there is a much better approach. Note the change to the title. Have included minor corrections following revie

    Case-control study of stroke and the quality of hypertension control in north west England

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    Objective: To examine the risk of stroke in relation to quality of hypertension control in routine general practice across an entire health district. Design: Population based matched case-control study. Setting: East Lancashire Health District with a participating population of 388,821 aged < or = 80. Subjects: Cases were patients under 80 with their first stroke identified from a population based stroke register between 1 July 1994 and 30 June 1995. For each case two controls matched with the case for age and sex were selected from the same practice register. Hypertension was defined as systolic blood pressure > or = 160 mm Hg or diastolic blood pressure > or = 95 mm Hg, or both, on at least two occasions within any three month period or any history of treatment with antihypertensive drugs. Main outcome measures: Prevalence of hypertension and quality of control of hypertension assessed by using the mean blood pressure recorded before stroke) and odds ratios of stroke (derived from conditional logistic regression). Results: Records of 267 cases and 534 controls were examined; 61% and 42% of these subjects respectively were hypertensive. Compared with non-hypertensive subjects hypertensive patients receiving treatment whose average pre-event systolic blood pressure was controlled to or = 160 mm Hg) or untreated had progressively raised odds ratios of 1.6, 2.2, 3.2, and 3.5 respectively. Results for diastolic pressure were similar; both were independent of initial pressures before treatment. Around 21% of strokes were thus attributable to inadequate control with treatment, or 46 first events yearly per 100,000 population aged 40-79. Conclusions: Risk of stroke was clearly related to quality of control of blood pressure with treatment. In routine practice consistent control of blood pressure to below 150/90 mm Hg seems to be required for optimal stroke prevention

    A Survey of Preservice Teachers\u27 Attitudes on Integrating Students with Disabilities in Inclusive Education Classrooms

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    There are more than 2.4 million American public school students identified with learning disabilities who are served under the Individuals with Disabilities Education Act (IDEA). General education preservice teachers are expected to effectively teach all students, including those with disabilities. However, most teacher preparation programs only require a single course in teaching students with disabilities. Research shows that that teachers’ attitudes regarding inclusion are the greatest predictor of a successful inclusion classroom. This study explored the attitudes of preservice elementary and preservice secondary teachers regarding integrating students with disabilities into general education classrooms. A quantitative research design with a survey method was used in this study. The survey method included a questionnaire via Qualtrics, an online survey system used at the University of Central Florida. Findings of this study revealed that 40% of preservice teachers indicated that integrating students with disabilities in the general education class was a burden. However, due to information limitations the results for preservice elementary and preservice secondary teachers’ attitudes regarding the integration of students with disabilities in the general education classroom and the number of hours of service learning completed was inconclusive

    Influences on condom use: A secondary analysis of women's perceptions from the Australian Contraceptive ChOice pRoject (ACCORd) trial.

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    Background and objectives Women’s ability to negotiate condom use helps prevent sexually transmissible infections (STIs) and unintended pregnancies. The aim of this study was to assess the relationship between substance use, risk perception and the certainty of using condoms in several hypothetical situations. Methods This is a secondary analysis from the Australian Contraceptive ChOice pRoject (ACCORd) cluster randomised controlled trial. Descriptive statistics and logistic regression were used for the analysis. Results At baseline, contraceptive questions were answered by 698 women attending 57 general practices in Melbourne, Australia. Condom use was reported by 47%. Of those using condoms as the sole form of contraception (n = 137), 20% used them inconsistently. Dual protection was used by 58% of women (188/325). Condoms and the pill were more frequently used than condoms and longer-acting contraceptives. Women were less likely to be confident negotiating condom use when using substances. Discussion Substance use and the concurrent use of other forms of contraception impact use of condoms. Even when condoms are the sole form of contraception with willing partners, use is inconsistent, leaving women at risk of pregnancy and STI

    Increasing the uptake of long-acting reversible contraception in general practice: the Australian Contraceptive ChOice pRoject (ACCORd) cluster randomised controlled trial longitudinal follow-up protocol.

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    IntroductionThrough addressing main barriers to the uptake of long-acting reversible contraceptives (LARCs) among Australian women, the Australian Contraceptive ChOice pRoject (ACCORd) trialled an educational intervention targeting general practitioners (GPs) and provided those in the intervention group with a rapid referral service for quick insertion. The cluster randomised controlled trial resulted in greater uptake of LARC in the intervention group. This protocol paper describes a longitudinal follow-up to the ACCORd Study to assess the long-term efficacy and cost-effectiveness of the intervention.Methods and analysisWomen participants (patients of ACCORd GPs) completed a baseline, 6-month and 12-month survey. These participants will be invited to complete an additional follow-up survey 3 years post completion of their baseline interview. Based on the original ACCORd Study tools, the online survey will address long-term outcomes including contraceptive continuation rates and reproductive history, any unintended pregnancies, satisfaction and concerns with their current contraceptive method, and an assessment of quality of life. We will analyse data using binary regression models with generalised estimating equations and robust standard errors to account for clustering.DiscussionDemonstration of sustained use, effectiveness at reducing unwanted pregnancies and cost-effectiveness of this strategy among this cohort of Australian primary care patients, will strengthen the policy and programme urgency of addressing wider dissemination of these strategies and replicating the study elsewhere.Ethics and disseminationThe ACCORd Study received approval from the Monash University Human Research Ethics Committee: CF16/188-201000080. Additionally, an amendment to conduct this 3-year longitudinal follow-up survey has been approved. The trial follow-up outcomes will be disseminated through formal academic pathways, including journal articles, national and international conferences and reports as well as using more 'mainstream' strategies such as seminars, workshops and media engagement. Additionally, outcomes will be communicated through policy briefs to Australian state and federal governments.Trail registration numberThis trial is registered with the Australian and New Zealand Trials Registry ACTRN12615001346561. Recruitment and data collection have been completed for the baseline, 6-month and 12-month surveys. Data collection for the 3-year survey commenced in August 2019

    'The difference in determinants of Chlamydia trachomatis and Mycoplasma genitalium in a sample of young Australian women.'

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    BACKGROUND Differences in the determinants of Chlamydia trachomatis ('chlamydia') and Mycoplasma genitalium (MG) genital infection in women are not well understood. METHODS A cohort study of 16 to 25 year old Australian women recruited from primary health care clinics, aimed to determine chlamydia and MG prevalence and incidence. Vaginal swabs collected at recruitment were used to measure chlamydia and MG prevalence, organism-load and chlamydia-serovar a cross-sectional analysis undertaken on the baseline results is presented here. RESULTS Of 1116 participants, chlamydia prevalence was 4.9% (95% CI: 2.9, 7.0) (n = 55) and MG prevalence was 2.4% (95% CI: 1.5, 3.3) (n = 27). Differences in the determinants were found - chlamydia not MG, was associated with younger age [AOR:0.9 (95% CI: 0.8, 1.0)] and recent antibiotic use [AOR:0.4 (95% CI: 0.2, 1.0)], and MG not chlamydia was associated with symptoms [AOR:2.1 (95% CI: 1.1, 4.0)]. Having two or more partners in last 12 months was more strongly associated with chlamydia [AOR:6.4 (95% CI: 3.6, 11.3)] than MG [AOR:2.2 (95% CI: 1.0, 4.6)] but unprotected sex with three or more partners was less strongly associated with chlamydia [AOR:3.1 (95%CI: 1.0, 9.5)] than MG [AOR:16.6 (95%CI: 2.0, 138.0)]. Median organism load for MG was 100 times lower (5.7 × 104/swab) than chlamydia (5.6 × 10⁶/swab) (p < 0.01) and not associated with age or symptoms for chlamydia or MG. CONCLUSIONS These results demonstrate significant chlamydia and MG prevalence in Australian women, and suggest that the differences in strengths of association between numbers of sexual partners and unprotected sex and chlamydia and MG might be due to differences in the transmission dynamics between these infections.This project was funded by the Commonwealth of Australia, as part of a National Chlamydia Pilot program that is currently running to test the effectiveness of a number of models for chlamydia testing in Australia. This project will assist in developing possible recommendations for a National Chlamydia Program. The analysis of MG was funded by the National Health and Research Council (research grant number 509144)

    Strangeness in the Scalar Form Factor of the Nucleon

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    The scalar form factor of the nucleon and related physical quantities are investigated in the framework of the semibosonized SU(3) Nambu-Jona-Lasinio soliton model. We take into account the rotational 1/Nc1/N_c corrections and linear msm_s corrections. The strangeness content of the nucleon in the scalar form factor is discussed in detail. In particular, it is found that the msm_s corrections play an essential role of reducing the ⟨N∣sˉs∣N⟩\langle N | \bar{s} s | N \rangle arising from the leading order and rotational 1/Nc1/N_c contributions. We obtain the \sigma_{\pi N} (0)=40.80\;\mbox{MeV}, \Delta \sigma = \sigma_{\pi N} (2m^{2}_{\pi})-\sigma_{\pi N} (0) = 18.18\;\mbox{MeV} and \langle r^2\rangle^{S}_{N} = 1.50\;\mbox{fm}^2. The results are in a remarkable agreement with empirical data analyzed by Gasser, Leutwyler, and Sainio~\cite{gls}.Comment: 13 pages, RevTex is used. 3 figures as uufiles are include

    Cost-effectiveness of a complex intervention in general practice to increase uptake of long-acting reversible contraceptives in Australia.

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    Objective The aim of this study was to evaluate the cost-effectiveness of the Australian Contraceptive ChOice pRoject (ACCORd) intervention. Methods An economic evaluation compared the costs and outcomes of the ACCORd intervention with usual care (UC). Data from the ACCORd trial were used to estimate costs and efficacy in terms of contraceptive uptake and quality of life. Rates of contraceptive failure and pregnancy were sourced from the literature. Using a Markov model, within-trial results were extrapolated over 10 years and subjected to univariate sensitivity analyses. Model outputs were expressed as the cost per quality-adjusted life years (QALY) gained and cost per unintended pregnancy resulting in birth (UPB) avoided. Results Over 10 years, compared with UC, initiating contraception through the ACCORd intervention resulted in 0.02 fewer UPB and higher total costs (A2505vsA2505 vs A1179) per woman. The incremental cost-effectiveness of the ACCORd intervention versus UC was A1172perQALYgainedandA1172 per QALY gained and A7385 per UPB averted. If the start-up cost of the ACCORd intervention was removed, the incremental cost-effectiveness ratio was A81perQALYgainedandA81 per QALY gained and A511 per UPB averted. The results were most sensitive to the probability of contraceptive failure, the probability of pregnancy-related healthcare service utilisation or the inclusion of the costs of implementing the ACCORd intervention. Conclusions From a health system perspective, if implemented appropriately in terms of uptake and reach, and assuming an implicit willingness to pay threshold of A$50 000 the ACCORd intervention is cost-effective. What is known about the topic? The uptake of long-active reversible contraceptives (LARC) in Australia is low. The ACCORd trial assessed the efficacy of providing structured training to general practitioners (GPs) on LARC counselling, together with access to rapid referral to insertion clinics. What does this paper add? This study is the first to assess the cost-effectiveness of a complex intervention in the general practice setting aimed at increasing the uptake of LARC in Australia. What are the implications for practitioners? The results show that implementing a complex intervention in general practice involving GP education and the availability of rapid referral to LARC insertion clinics is a cost-effective approach to increase LARC use and its attending efficacy. If the majority of Australian GPs were able to deliver effectiveness-based contraceptive counselling and either insert LARC or use a rapid referral process to a LARC insertion clinic, the additional cost associated with the purchase of LARC products and their insertion would be offset by reductions to health system costs as a result of fewer UPB and abortions. Moreover, the benefits to women's physical and psychological health of avoiding such events is substantial
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