145 research outputs found
Convex Regularization Method for Solving Cauchy Problem of the Helmholtz Equation
In this paper, we introduce the Convex Regularization Method (CRM) for regularizing the (instability) solution of the Helmholtz equation with Cauchy data. The CRM makes it possible for the solution of Helmholtz equation to depend continuously on the small perturbations in the Cauchy data. In addition, the numerical computation of the reg- ularized Helmholtz equation with Cauchy data is stable, accurate and gives high rate of convergence of solution in Hilbert space. Undoubtedly, the error estimated analysis associated with CRM is minimal.Mathematics Subject Classi cation: 44B28; 44B30Keywords: Convex Regularization Method, ill-posed Helmholtz equation with Cauchy data, stable solutio
A Two-Dimensional Chebyshev Wavelet Method for Solving Partial Di erential Equations
In this paper, we introduce a two-dimensional Chebyshev wavelet method (TCWM) for solving partial di erential equations (PDEs) in L2(R) space. In this method, the spatial variables appearing in the PDE each has its own kernel, as well as wavelet coecient for approxi- mating the unknown solution of the equation. The approximated solu- tion of the equation is fast and has higher number of vanishing moments as compared to the Chebyshev wavelet method with only one wavelet coecient for two or more separated kernels for the variables appearing in the PDE
Sexual identity, attraction and behaviour in Britain: The implications of using different dimensions of sexual orientation to estimate the size of sexual minority populations and inform public health interventions.
BACKGROUND: Sexual orientation encompasses three dimensions: sexual identity, attraction and behaviour. There is increasing demand for data on sexual orientation to meet equality legislation, monitor potential inequalities and address public health needs. We present estimates of all three dimensions and their overlap in British men and women, and consider the implications for health services, research and the development and evaluation of public health interventions. METHODS: Analyses of data from Britain's third National Survey of Sexual Attitudes and Lifestyles, a probability sample survey (15,162 people aged 16-74 years) undertaken in 2010-2012. FINDINGS: A lesbian, gay or bisexual (LGB) identity was reported by 2·5% of men and 2·4% of women, whilst 6·5% of men and 11·5% of women reported any same-sex attraction and 5·5% of men and 6·1% of women reported ever experience of same-sex sex. This equates to approximately 547,000 men and 546,000 women aged 16-74 in Britain self-identifying as LGB and 1,204,000 men and 1,389,000 women ever having experience of same-sex sex. Of those reporting same-sex sex in the past 5 years, 28% of men and 45% of women identified as heterosexual. INTERPRETATION: There is large variation in the size of sexual minority populations depending on the dimension applied, with implications for the design of epidemiological studies, targeting and monitoring of public health interventions and estimating population-based denominators. There is also substantial diversity on an individual level between identity, behaviour and attraction, adding to the complexity of delivering appropriate services and interventions
Asking about Sex in General Health Surveys: Comparing the Methods and Findings of the 2010 Health Survey for England with Those of the Third National Survey of Sexual Attitudes and Lifestyles
Including questions about sexual health in the annual Health Survey for England (HSE) provides opportunities for regular measurement of key public health indicators, augmenting Britain's decennial National Survey of Sexual Attitudes and Lifestyles (Natsal). However, contextual and methodological differences may limit comparability of the findings. We examine the extent of these differences between HSE 2010 and Natsal-3 and investigate their impact on parameter estimates
Help-Seeking for Sexual Difficulties and the Potential Role of Interactive Digital Interventions: Findings From the Third British National Survey of Sexual Attitudes and Lifestyles
Sexual difficulties are common and can negatively impact health and well-being. A wide range of support is available, but there are multiple barriers to accessing help. Interactive digital interventions (IDIs) for sexual difficulties have the potential to provide a convenient, wide-reaching, and cost-effective source of support, but little is known about who might use them. We explored the potential reach of IDIs by assessing the prevalence of help-seeking among people with distressing sexual difficulties, including who seeks which sources of help. Data came from sexually active men and women, ages 16 to 74, participating in Britain's third National Survey of Sexual Attitudes and Lifestyles (Natsal-3) (N = 11,637). Help/advice was sought by less than half of those with distressing sexual difficulties, and help-seeking was associated with younger age in women but not men. The most popular sources of support were family doctor (47.5% to 54.8%), Internet (22.0% to 25.6%), and family/friend (20.7% to 41.8%), with older participants (≥ 35), particularly men, preferring to seek help from a family doctor, and younger participants (<35) preferring to seek help from the Internet or family/friend. Despite a paucity of good digital support sites for sexual function, the Internet is a common source of help. As Internet access continues to increase, so too does the potential for well-designed IDIs to support those with sexual difficulties
Genomic epidemiological analysis identifies high relapse among individuals with recurring tuberculosis and provides evidence of household recent TB transmission in Ghana
OBJECTIVE: We investigated the cause of recurring tuberculosis (rcTB) among pulmonary TB participants recruited from a prospective population-based study conducted between July 2012 and December 2015. METHODS: Mycobacterium tuberculosis complex isolates obtained from rcTB cases were characterized by standard mycobacterial genotyping tools in addition to whole genome sequencing, followed by phylogenetic analysis to assess strain relatedness. RESULTS: A greater proportion (58.3%, 21/36) of individuals with rcTB episodes had TB recurrence within 12 months post treatment. Only 19.4% (7/36) of participants with rcTB harbored a strain with isoniazid (INH) resistance at baseline of which 29% (2/7) were additionally resistant to rifampicin. However, 27.8% (10/36) harbored an INH resistant strain upon recurring of which 40% (4/10) were MDR-TB strains. Recurrent TB was attributed to relapse (same strain) in 75.0% (27/36) of participants with 25.0% (9/36) attributed to re-infection. CONCLUSION: Our findings indicate that unresolved previous infection due to inadequate treatment may be the major cause of rcTB
Toward Uniform Implementation Of Parametric Map Digital Imaging And Communication In Medicine Standard In Multisite Quantitative Diffusion Imaging Studies
This paper reports on results of a multisite collaborative project launched by the MRI subgroup of Quantitative Imaging Network to assess current capability and provide future guidelines for generating a standard parametric diffusion map Digital Imaging and Communication in Medicine (DICOM) in clinical trials that utilize quantitative diffusion-weighted imaging (DWI). Participating sites used a multivendor DWI DICOM dataset of a single phantom to generate parametric maps (PMs) of the apparent diffusion coefficient (ADC) based on two models. The results were evaluated for numerical consistency among models and true phantom ADC values, as well as for consistency of metadata with attributes required by the DICOM standards. This analysis identified missing metadata descriptive of the sources for detected numerical discrepancies among ADC models. Instead of the DICOM PM object, all sites stored ADC maps as DICOM MR objects, generally lacking designated attributes and coded terms for quantitative DWI modeling. Source-image reference, model parameters, ADC units and scale, deemed important for numerical consistency, were either missing or stored using nonstandard conventions. Guided by the identified limitations, the DICOM PM standard has been amended to include coded terms for the relevant diffusion models. Open-source software has been developed to support conversion of site-specific formats into the standard representation
Olfaction: anatomy, physiology and behavior
The anatomy, physiology and function of the olfactory system are reviewed, as are the normal effects of olfactory stimulation. It is speculated that olfaction may have important but unobtrusive effects on human behavior
Cost-Effectiveness of Peer-Delivered Interventions for Cocaine and Alcohol Abuse among Women: A Randomized Controlled Trial
<div><h3>Aims</h3><p>To determine whether the additional interventions to standard care are cost-effective in addressing cocaine and alcohol abuse at 4 months (4 M) and 12 months (12 M) from baseline.</p> <h3>Method</h3><p>We conducted a cost-effectiveness analysis of a randomized controlled trial with three arms: (1) NIDA's Standard intervention (SI); (2) SI plus a Well Woman Exam (WWE); and, (3) SI, WWE, plus four Educational Sessions (4ES).</p> <h3>Results</h3><p>To obtain an additional cocaine abstainer, WWE compared to SI cost 3,611 at 12 M. Per additional alcohol abstainer, WWE compared to SI cost 7,223 at 4 M and 12 M, respectively. At 12 M, 4ES was dominated (more costly and less effective) by WWE for abstinence outcomes.</p> <h3>Conclusions</h3><p>To our knowledge, this is the first cost-effectiveness analysis simultaneously examining cocaine and alcohol abuse in women. Depending on primary outcomes sought and priorities of policy makers, peer-delivered interventions can be a cost-effective way to address the needs of this growing, underserved population.</p> <h3>Trial Registration</h3><p>ClinicalTrials.gov <a href="http://www.clinicaltrials.gov/ct2/show/NCT01235091">NCT01235091</a></p> </div
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