98 research outputs found

    Acoustic particle separation

    Get PDF
    A method is described which uses acoustic energy to separate particles of different sizes, densities, or the like. The method includes applying acoustic energy resonant to a chamber containing a liquid of gaseous medium to set up a standing wave pattern that includes a force potential well wherein particles within the well are urged towards the center, or position of minimum force potential. A group of particles to be separated is placed in the chamber, while a non-acoustic force such as gravity is applied, so that the particles separate with the larger or denser particles moving away from the center of the well to a position near its edge and progressively smaller lighter particles moving progressively closer to the center of the well. Particles are removed from different positions within the well, so that particles are separated according to the positions they occupy in the well

    Using health surveillance systems data to assess the impact of AIDS and antiretroviral treatment on adult morbidity and mortality in Botswana

    Get PDF
    Introduction: Botswana's AIDS response included free antiretroviral treatment (ART) since 2002, achieving 80% coverage of persons with CD450% and >30% through 2011, while continuing to increase in older women. Conclusions: Adult mortality in Botswana fell markedly as ART coverage increased. HIV prevalence declines may reflect ART-associated reductions in sexual transmission. Triangulation of surveillance system data offers a reasonable approach to evaluate impact of HIV/AIDS interventions, complementing cohort approaches that monitor individual-level health outcomes

    Uganda's HIV Prevention Success: The Role of Sexual Behavior Change and the National Response

    Get PDF
    There has been considerable interest in understanding what may have led to Uganda's dramatic decline in HIV prevalence, one of the world's earliest and most compelling AIDS prevention successes. Survey and other data suggest that a decline in multi-partner sexual behavior is the behavioral change most likely associated with HIV decline. It appears that behavior change programs, particularly involving extensive promotion of “zero grazing” (faithfulness and partner reduction), largely developed by the Ugandan government and local NGOs including faith-based, women’s, people-living-with-AIDS and other community-based groups, contributed to the early declines in casual/multiple sexual partnerships and HIV incidence and, along with other factors including condom use, to the subsequent sharp decline in HIV prevalence. Yet the debate over “what happened in Uganda” continues, often involving divisive abstinence-versus-condoms rhetoric, which appears more related to the culture wars in the USA than to African social reality

    Deterrence in Cyberspace: An Interdisciplinary Review of the Empirical Literature

    Get PDF
    The popularity of the deterrence perspective across multiple scientific disciplines has sparked a lively debate regarding its relevance in influencing both offenders and targets in cyberspace. Unfortunately, due to the invisible borders between academic disciplines, most of the published literature on deterrence in cyberspace is confined within unique scientific disciplines. This chapter therefore provides an interdisciplinary review of the issue of deterrence in cyberspace. It begins with a short overview of the deterrence perspective, presenting the ongoing debates concerning the relevance of deterrence pillars in influencing cybercriminals’ and cyberattackers’ operations in cyberspace. It then reviews the existing scientific evidence assessing various aspects of deterrence in the context of several disciplines: criminology, law, information systems, and political science. This chapter ends with a few policy implications and proposed directions for future interdisciplinary academic research

    Civil society leadership in the struggle for AIDS treatment in South Africa and Uganda

    Get PDF
    Includes abstract.Includes bibliographical references.This thesis is an attempt to theorise and operationalise empirically the notion of ‘civil society leadership’ in Sub-Saharan Africa. ‘AIDS leadership,’ which is associated with the intergovernmental institutions charged with coordinating the global response to HIV/AIDS, is both under-theorised and highly context-specific. In this study I therefore opt for an inclusive framework that draws on a range of approaches, including the literature on ‘leadership’, institutions, social movements and the ‘network’ perspective on civil society mobilisation. This framework is employed in rich and detailed empirical descriptions (‘thick description’) of civil society mobilisation around AIDS, including contentious AIDS activism, in the key case studies of South Africa and Uganda. South Africa and Uganda are widely considered key examples of poor and good leadership (from national political leaders) respectively, while the Treatment Action Campaign (TAC) and The AIDS Support Organisation (TASO) are both seen as highly effective civil society movements. These descriptions emphasise ‘transnational networks of influence’ in which civil society leaders participated (and at times actively constructed) in order to mobilise both symbolic and material resources aimed at exerting influence at the transnational, national and local levels

    Pattern and levels of spending allocated to HIV prevention programs in low- and middle-income countries

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>AIDS continues to spread at an estimated 2.6 new million infections per year, making the prevention of HIV transmission a critical public health issue. The dramatic growth in global resources for AIDS has produced a steady scale-up in treatment and care that has not been equally matched by preventive services. This paper is a detailed analysis of how countries are choosing to spend these more limited prevention funds.</p> <p>Methods</p> <p>We analyzed prevention spending in 69 low- and middle-income countries with a variety of epidemic types, using data from national domestic spending reports. Spending information was from public and international sources and was analyzed based on the National AIDS Spending Assessment (NASA) methods and classifications.</p> <p>Results</p> <p>Overall, prevention received 21% of HIV resources compared to 53% of funding allocated to treatment and care. Prevention relies primarily on international donors, who accounted for 65% of all prevention resources and 93% of funding in low-income countries. For the subset of 53 countries that provided detailed spending information, we found that 60% of prevention resources were spent in five areas: communication for social and behavioral change (16%), voluntary counselling and testing (14%), prevention of mother-to-child transmission (13%), blood safety (10%) and condom programs (7%). Only 7% of funding was spent on most-at-risk populations and less than 1% on male circumcision. Spending patterns did not consistently reflect current evidence and the HIV specific transmission context of each country.</p> <p>Conclusions</p> <p>Despite recognition of its importance, countries are not allocating resources in ways that are likely to achieve the greatest impact on prevention across all epidemic types. Within prevention spending itself, a greater share of resources need to be matched with interventions that approximate the specific needs and drivers of each country's epidemic.</p

    Understanding the Impact of Male Circumcision Interventions on the Spread of HIV in Southern Africa

    Get PDF
    BACKGROUND: Three randomised controlled trials have clearly shown that circumcision of adult men reduces the chance that they acquire HIV infection. However, the potential impact of circumcision programmes--either alone or in combination with other established approaches--is not known and no further field trials are planned. We have used a mathematical model, parameterised using existing trial findings, to understand and predict the impact of circumcision programmes at the population level. FINDINGS: Our results indicate that circumcision will lead to reductions in incidence for women and uncircumcised men, as well as those circumcised, but that even the most effective intervention is unlikely to completely stem the spread of the virus. Without additional interventions, HIV incidence could eventually be reduced by 25-35%, depending on the level of coverage achieved and whether onward transmission from circumcised men is also reduced. However, circumcision interventions can act synergistically with other types of prevention programmes, and if efforts to change behaviour are increased in parallel with the scale-up of circumcision services, then dramatic reductions in HIV incidence could be achieved. In the long-term, this could lead to reduced AIDS deaths and less need for anti-retroviral therapy. Any increases in risk behaviours following circumcision, i.e. 'risk compensation', could offset some of the potential benefit of the intervention, especially for women, but only very large increases would lead to more infections overall. CONCLUSIONS: Circumcision will not be the silver bullet to prevent HIV transmission, but interventions could help to substantially protect men and women from infection, especially in combination with other approaches
    corecore