71 research outputs found
The strategic use and potential demand for an HIV vaccine in Southern Africa
HIV prevalence in Southern Africa is the highest in the world and the impact of HIV/AIDS in the region are devastating at all levels of society, including the wider economy. Government response has lagged behind the pace of the epidemic, but programs are now beginning to focus on a broad range of interventions to combat its further spread and to mitigate its impact. The authors investigate the issues around the targeting of an eventual HIV vaccine. There is at present no vaccine against HIV. Although several candidates are in the trial stage, it is not likely that a vaccine effective against the sub-type of the virus prevalent in Southern Africa will be available for 10-15 years. When it is, it may be expensive, only partially effective, and confer immunity for a limited period only. Vaccination programs will need to make the best use of the vaccine that is available and effective targeting will be essential. The authors identify potential target groups for a vaccine, and estimate how many individuals would be in need of vaccination. They develop a method for estimating how many cases of HIV infection are likely to be avoided for each vaccinated individual. The cases avoided are of two kinds: primary-the individual case that might have occurred in people who are vaccinated, and secondary-the number of people that the vaccinated individual would otherwise have caused to become infected. Both ofthese depend on assumptions about the efficacy and duration of vaccine protection and the extent and nature of sexual risk behavior in the population groups. The authors distinguish between the HIV cases averted per vaccination and the cases averted per 100 recruits into a vaccination program. The cases averted per 100 recruits is used to develop a priority ranking of the identified population groups for vaccination. The authors discuss the issue of ease of access to those groups and how the differential costs would affect the vaccination strategy. They conclude that an expensive vaccine should be administered to commercial sex workers first, while an inexpensive vaccine would be better administered first to general population groups, in particular, schoolchildren. The authors conclude with a discussion of current levels of public and private expenditure on HIV prevention and treatment, and the implications for an assessment of the willingness to pay for an eventual HIV vaccine.Disease Control&Prevention,Health Monitoring&Evaluation,HIV AIDS,Public Health Promotion,Early Child and Children's Health,Adolescent Health,Health Economics&Finance,HIV AIDS and Business,Health Monitoring&Evaluation,HIV AIDS
U.S. Army Physician Assistant Retention: A Latent Class Analysis
Introduction: Retaining employees is crucial to the success of organizations. While significant effort has been made to model employee retention, models have been unable to significantly predict retention. The purpose of this quantitative, non-experimental, cross-sectional study was to develop an improved employee retention model which could be used as a practical guide to improve employee retention. Materials and Methods: The study analyzed a survey created, implemented, and collected by the Statistical Cell at the U.S. Army Center of Excellence. In September of 2020, all 864 active-duty PAs were sent a link to the survey and 290 completed the survey, for a participation rate of 33.6%. The study used a combination of population-based regression analysis and subgroup-based latent class analysis. To guide the study a conceptual model combined a population-based retention model (Causal Model of Turnover) with a subgroup-based person-centered model (Proximal Withdrawal State Theory). IRB approval was obtained thru the U.S. Army Medical Center of Excellence and University of the Incarnate Word. Results: Multivariate logistical regression found belief career goals were achievable in Army medicine (adjusted odds ratio 0.74, 95% CI 0.57, 0.98), age (adjusted odds ratio 0.63, 95% CI 0.41, 0.98), and perception DHA control of Army medicine affects retention (adjusted odds ratio 0.54, 95% CI 0.39, 0.75) as factors able to predict the intent to serve 20 years in the Army. Latent Class Analysis (LCA) divided the population into three groups, the sensitive stayers, moderates, and indifferent leavers. The sensitive stayers had the highest retention (0.93) and were most likely to be concerned about variables affecting retention. The indifferent leavers had the lowest retention (0.68) and the least concern for variables affecting retention. The moderates fell in between the other two groups. Belief career goals were achievable in Army Medicine was the only variable able to predict class memberships in the three classes of LCA (p \u3c .001). A revised conceptual model was improved by adding perception career goals were achievable in the organization to better unify the model. Conclusions: The extent goals are perceived to be achievable in the current job create job satisfaction and organizational commitment which strengthens intent to stay. Career goals vary based on the individual and accounting for these individual preferences provides a bridge to cohesively unite population-based retention models with person centered retention models. Strengths of this study include the incorporation of two leading retention theories into one cohesive model improved by the study using results triangulated with multiple statistical techniques and past criticisms of retention theories. Weaknesses include the use of secondary cross-sectional data not designed to support the conceptual framework and the population was limited to only U.S. Army PAs. Future studies should utilize experimental longitudinal studies to consider how the perception of career goals being achievable in an organization can be improved to increase retention
Squaring the Circle: AIDS, Poverty, and Human Development
The authors discuss the "downstream" effects of AIDS on poverty, and the "upstream" effects of poverty upon acquiring HIV
Achieving the WHO/UNAIDS antiretroviral treatment 3 by 5 goal: what will it cost?
The "3 by 5" goal to have 3 million people in low and middle income countries on antiretroviral therapy (ART) by the end of 2005 is ambitious. Estimates of the necessary resources are needed to facilitate resource mobilisation and rapid channelling of funds to where they are required. We estimated the financial costs needed to implement treatment protocols, by use of country-specific estimates for 34 countries that account for 90% of the need for ART in resource-poor settings. We first estimated the number of people needing ART and supporting programmes for each country. We then estimated the cost per patient for each programme by country to derive total costs. We estimate that between US5.1 billion dollars and US5.9 billion dollars will be needed by the end of 2005 to provide ART, support programmes, and cover country-level administrative and logistic costs for 3 by 5
One-step fabrication of microchannels with integrated three dimensional features by hot intrusion embossing
We build on the concept of hot intrusion embossing to develop a one-step fabrication
method for thermoplastic microfluidic channels containing integrated three-dimensional features.
This was accomplished with simple, rapid-to-fabricate imprint templates containing microcavities
that locally control the intrusion of heated thermoplastic based on their cross-sectional geometries.
The use of circular, rectangular and triangular cavity geometries was demonstrated for the
purposes of forming posts, multi-focal length microlense arrays, walls, steps, tapered features and
three-dimensional serpentine microchannels. Process variables, such as temperature and pressure,
controlled feature dimensions without affecting the overall microchannel geometry. The approach
was demonstrated for polycarbonate, cycloolefin copolymer and polystyrene, but in principle is
applicable to any thermoplastic. The approach is a step forward towards rapid fabrication of complex,
robust, microfluidic platforms with integrated multi-functional elements
Associations between area deprivation and changes in the digital food environment during the COVID-19 pandemic: Longitudinal analysis of three online food delivery platforms.
Online food delivery services facilitate access to unhealthy foods and have proliferated during the COVID-19 pandemic. This study explores associations between neighbourhood deprivation and exposure to online food delivery services and changes in exposure by deprivation during the first year of the pandemic. Data on food outlets delivering to 661 postcode districts in London and the North of England in 2020 and 2021 were collected from three online delivery platforms. The association between area deprivation and overall exposure to online food delivery services was moderated by region, with evidence of a positive relationship between count of outlets and deprivation in the North of England, and a negative relationship in London. There was no association between area deprivation and growth of online food delivery services. Associations between neighbourhood deprivation and exposure to the digital food environment vary geographically. Consequently, policies aimed at the digital food environment need to be tailored to the local context
3D LIDAR imaging using Ge-on-Si single–photon avalanche diode detectors
We present a scanning light detection and ranging (LIDAR) system incorporating an individual Ge-on-Si single-photon avalanche diode (SPAD) detector for depth and intensity imaging in the short-wavelength infrared region. The time-correlated single-photon counting technique was used to determine the return photon time-of-flight for target depth information. In laboratory demonstrations, depth and intensity reconstructions were made of targets at short range, using advanced image processing algorithms tailored for the analysis of single–photon time-of-flight data. These laboratory measurements were used to predict the performance of the single-photon LIDAR system at longer ranges, providing estimations that sub-milliwatt average power levels would be required for kilometer range depth measurements
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Changes in household food and drink purchases following restrictions on the advertisement of high fat, salt, and sugar products across the Transport for London network: A controlled interrupted time series analysis.
Funder: Cancer Research UKBACKGROUND: Restricting the advertisement of products with high fat, salt, and sugar (HFSS) content has been recommended as a policy tool to improve diet and tackle obesity, but the impact on HFSS purchasing is unknown. This study aimed to evaluate the impact of HFSS advertising restrictions, implemented across the London (UK) transport network in February 2019, on HFSS purchases. METHODS AND FINDINGS: Over 5 million take-home food and drink purchases were recorded by 1,970 households (London [intervention], n = 977; North of England [control], n = 993) randomly selected from the Kantar Fast Moving Consumer Goods panel. The intervention and control samples were similar in household characteristics but had small differences in main food shopper sex, socioeconomic position, and body mass index. Using a controlled interrupted time series design, we estimated average weekly household purchases of energy and nutrients from HFSS products in the post-intervention period (44 weeks) compared to a counterfactual constructed from the control and pre-intervention (36 weeks) series. Energy purchased from HFSS products was 6.7% (1,001.0 kcal, 95% CI 456.0 to 1,546.0) lower among intervention households compared to the counterfactual. Relative reductions in purchases of fat (57.9 g, 95% CI 22.1 to 93.7), saturated fat (26.4 g, 95% CI 12.4 to 40.4), and sugar (80.7 g, 95% CI 41.4 to 120.1) from HFSS products were also observed. Energy from chocolate and confectionery purchases was 19.4% (317.9 kcal, 95% CI 200.0 to 435.8) lower among intervention households than for the counterfactual, with corresponding relative reductions in fat (13.1 g, 95% CI 7.5 to 18.8), saturated fat (8.7 g, 95% CI 5.7 to 11.7), sugar (41.4 g, 95% CI 27.4 to 55.4), and salt (0.2 g, 95% CI 0.1 to 0.2) purchased from chocolate and confectionery. Relative reductions are in the context of secular increases in HFSS purchases in both the intervention and control areas, so the policy was associated with attenuated growth of HFSS purchases rather than absolute reduction in HFSS purchases. Study limitations include the lack of out-of-home purchases in our analyses and not being able to assess the sustainability of observed changes beyond 44 weeks. CONCLUSIONS: This study finds an association between the implementation of restrictions on outdoor HFSS advertising and relative reductions in energy, sugar, and fat purchased from HFSS products. These findings provide support for policies that restrict HFSS advertising as a tool to reduce purchases of HFSS products
Putting It Together: AIDS and the Millennium Development Goals
Failure to halt and reverse the HIV/AIDS epidemic, say the authors, will continue to jeopardize progress on achieving a wide range of the MDGs
Ge-on-Si Single Photon Avalanche Diode Detectors for LIDAR in the Short Wave Infrared
Ge-on-Si single photon avalanche diodes are used to demonstrate LIDAR in laboratory conditions. Modelling demonstrates that eye-safe kilometre range-finding is achievable at 1450nm wavelength. Afterpulsing is found to be considerably lower than commercial InGaAs/InP devices
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