439 research outputs found

    What Advertisers Want: Measuring Institutions: Indicators of Political Rights, Property Rights and Political Instability in Malawi

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    In the 2008 Budget Review, the South African government announced its intention to levy a 2c/kWh tax on the sale of electricity generated from non-renewable sources. This measure is intended to serve a dual purpose of helping to manage the current electricity supply shortages and to protect the environment (National Treasury 2008). An electricity generation tax is set to have an impact on the South African economy. However, several instruments have been proposed in the literature to protect the competitiveness and economy of a country when it imposes a green tax, one of these remedies being border tax adjustments.This paper evaluates the effectiveness for the South African case, of border tax adjustments (BTAs) in counteracting the negative impact of an electricity generation tax on competitiveness. The remedial effects of the BTAs are assessed in the light of their ability to maintain the environmental benefits of the electricity generation tax. Additionally, the the Global Trade Analysis Project (GTAP) model is used to evaluate the impact of an electricity generation tax on the South African, SACU and SADC economies and to explore the possibility of reducing the economic impact of the electricity generation tax through BTAs. The results show that an electricity generation tax will lead to a contraction in South African gross domestic product (GDP). Traditional BTAs are unable to address these negative impacts. We propose a reversedBTA approach where gains from trade are utilised to counteract the negative effects of an electricity generation tax, while retaining the environmental benefits associated with the electricity generation tax. This is achieved through a lowering of import tariffs, as this will reduce production costs and thereby restore the competitiveness of the South African economy. The reduction in import tariffs not only negates the negative GDP impact of the electricity generation tax, but the bulk of CO2 abatement from the electricity generation tax is retained.

    AE Aquarii: A Short Review

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    The nova-like variable AE Aquarii has been continuously studied since its discovery on photographic plates in 1934. In this short review the peculiar multi-wavelength properties of AE Aquarii will be reviewed and explained in context of its evolution from a high mass transfer phase, during which period it could have been a supersoft X-ray source (SSS)

    Supporting Treatment for Anti-Retroviral Therapy (START) together: protocol for a pilot, randomized, couple-based intervention to promote women's ART adherence and men's engagement in HIV care in KwaZulu-Natal, South Africa

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    Background: South Africa currently has the greatest number of people with HIV globally. The country has not yet met its 95-95-95 goals, with different gaps in the HIV care cascade for women and men. This paper reports on a protocol to pilot test a couple-based intervention designed to improve women's antiretroviral therapy (ART) adherence and men's engagement in care in heterosexual couples living in the Vulindlela area of KwaZulu-Natal, South Africa. Study goals are two-fold: (1) assess the acceptability, feasibility, and fidelity of the experimental intervention, START Together, and (2) collect efficacy data on START Together for women's ART adherence, men's engagement in HIV care, and the couple's relationship functioning. Methods: Women (N = 20) who were not engaged with ART adherence (defined via self-reported ART difficulties, record of missed clinic visits, or viral non-suppression) are the target patients; male partners are not required to know or disclose their HIV status to be part of the study. Couples are randomized 1:1 to the experimental treatment (START Together) or treatment as usual (referrals to the local clinic to support ART adherence or any other HIV-related care). START Together is a 5-session intervention based in cognitive-behavioral couple therapy, which is a skill-based intervention focusing on communication and problem-solving skills, and Life Steps, a problem-solving intervention identifying barriers and solutions to medication adherence. Couples are assessed at baseline, post-treatment (8 weeks post-randomization), and follow-up (12 weeks post-randomization). Conclusion: This study will provide preliminary implementation and efficacy data on whether this novel approach has potential to improve women and men's HIV and healthcare-related needs

    Biological modelling of the radiation dose escalation effect of regional hyperthermia in cervical cancer

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    Background Locoregional hyperthermia combined with radiotherapy significantly improves locoregional control and overall survival for cervical tumors compared to radiotherapy alone. In this study biological modelling is applied to quantify the effect of radiosensitization for three cervical cancer patients to evaluate the improvement in equivalent dose for the combination treatment with radiotherapy and hyperthermia. Methods The Linear-Quadratic (LQ) model extended with temperature-dependent LQ-parameters α and β was used to model radiosensitization by hyperthermia and to calculate the conventional radiation dose that is equivalent in biological effect to the combined radiotherapy and hyperthermia treatment. External beam radiotherapy planning was performed based on a prescription dose of 46Gy in 23 fractions of 2Gy. Hyperthermia treatment using the AMC-4 system was simulated based on the actual optimized system settings used during treatment. Results The simulated hyperthermia treatments for the 3 patients yielded a T50 of 40.1 °C, 40.5 °C, 41.1 °C and a T90 of 39.2 °C, 39.7 °C, 40.4 °C, respectively. The combined radiotherapy and hyperthermia treatment resulted in a D95 of 52.5Gy, 55.5Gy, 56.9Gy in the GTV, a dose escalation of 7.3–11.9Gy compared to radiotherapy alone (D95 = 45.0–45.5Gy). Conclusions This study applied biological modelling to evaluate radiosensitization by hyperthermia as a radiation-dose escalation for cervical cancer patients. This model is very useful to compare the effectiveness of different treatment schedules for combined radiotherapy and hyperthermia treatments and to guide the design of clinical studies on dose escalation using hyperthermia in a multi-modality setting

    Development of a motion platform for an educational flight simulator

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    Flight simulators are regularly used in the undergraduate and postgraduate training of mechanical and aeronautical engineers. Due to advances in computing technology, several flight simulation-related tasks can now be accomplished in real-time using low-cost PC platforms and inexpensive commercial software. The difficulty in realising an educational flight simulator system with motion platform therefore lies with the design and construction of an effective motion platform. Costs become exorbitant when simulation platforms of more than two degrees of freedom (i.e. pitch and roll) are attempted. This paper describes the development of a drive system for a motion platform with two degrees of freedom (pitch and roll) for use in undergraduate engineering training. Use was made of off the-shelf PC equipment and flight simulation software and hardware, together with commercial actuators and drive systems. The motion platform was manufactured from square tubing and consisted of three frames: the stationary main frame and, rotating inside this, the roll frame and pitch frame. These rotated relative to each other and were actuated by two similar-sized DC motors and gearbox/ chain transmissions. The system effectively simulated the pitch and roll motions of commercial airliners, using a low-cost, easily maintainable motion platform. The educational value of the simulator was twofold: first, it was to be displayed in the science exploratorium (SciEnza) of the University of Pretoria; and second, it provided a platform on which mechanical (as well as electrical, electronic and computer) engineering students could conduct practical work in courses such as dynamics and control, and on which final-year and postgraduate students could conduct research.National Aerospace Centrehttp://www.manchesteruniversitypress.co.uk/cgi-bin/scribe?showinfo=ip017hb2016Mechanical and Aeronautical Engineerin
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