A Metric Inequality for the Thompson and Hilbert Geometries

There are two natural metrics defined on an arbitrary convex cone: Thompson's part metric and Hilbert's projective metric. For both, we establish an inequality giving information about how far the metric is from being non-positively curved.Comment: 15 pages, 0 figures. To appear in J. Inequalities Pure Appl. Mat

Manners and method in classical criticism of the early eighteenth century

This article explores a neglected period in the history of classical scholarship: the first decades of the eighteenth century. It focuses on the tension between an evolving idea of method, and the tradition of personal polemic which had been an important part of the culture of scholarship since the Renaissance. There are two case studies: the conflict between Jean Le Clerc and Pieter Burman, and the controversy that followed Richard Bentley's edition of Horace's Odes. Both demonstrate the need to revise current paradigms for writing the history of scholarship, and invite us to reconsider the role of methodology in producing of scholarly authority

The relationship between body mass index, energy intake and level of physical activity of HIV positive women (25-44 years) in Mangaung

Published ArticleObjective: To determine the relationship between body mass index (BMI), energy intake and levels of physical activity of HIV negative and HIV positive women. Design: Cross sectional study. Methodology: A random sample of 500 pre-menopausal women within the two age group categories of 25-34 and 35-44 years was selected. Data on physical activity was obtained using an adapted Baecke questionnaire and categorized into low, medium, and high levels of physical activity. Weight and height were used to calculate BMI. Dietary intake was determined by means of a standardized food frequency questionnaire. Results: Sixty-one percent of younger women and 38% of older women were HIV infected. The vast majority of women (91%) had low levels of physical activity, while only 9% of the sample had physical activity levels that fell within the normal to high category. More than 50% of respondents were either overweight or obese (BMI above 25 kg/m2). BMI of HIV positive younger women was, however, significantly lower than that of HIV negative women. Median energy intakes were high (more than 10 000 kJ) for both HIV positive and HIV negative women. Conclusions: Reverting to a more traditional lifestyle, including diet and physical activity, could assist in addressing unfavorable BMI parameters of these women and improve health status and quality of life of HIV infected women

Diabetes-related knowledge, attitude and practices (KAP) of adult patients with type 2 diabetes mellitus in the Free State province, South Africa

Introduction: Type 2 diabetes mellitus (T2DM) is a global health problem with high morbidity and mortality in patients who are mostly still economically active. The growing incidence and health implications for those affected make T2DM a major public health issue. Objectives: To compile a demographic, anthropometric and knowledge, attitude and practices (KAP) profile of adult patients with T2DM in the public health sector of the Free State province, South Africa. Design: A descriptive observational study was conducted. Setting: A total of 255 participants attending public health facilities in the Free State were interviewed. Outcome Measures: Questionnaires were completed in an interview to determine demographics and KAP. Anthropometric measurements were obtained by standard techniques. Results: The majority of the participants (n = 222; 87.1%) were black women from urban areas, who were overweight and obese. The median age at diagnosis was 48 years (range 15–80 years), and 25 participants (9.8%) lacked formal schooling. In 212 participants (83.1%), a waist circumference above cut-off points was observed. Only half of the participants knew the normal range for blood glucose. Approximately 80% felt that they would be a different person if they did not have diabetes. Although 96.1% of participants were knowledgeable about the benefits of physical exercise, only 31.0% reported exercising on a daily basis. A statistically significant association was found between knowledge and attitudes, indicating that better knowledge about diabetes could be associated with a more positive attitude towards diabetes. Conclusion: Poor knowledge, a negative attitude and poor practices related to diabetes were observed in a very high percentage of participants, which may contribute to morbidity and mortality. The fact that knowledge was associated with attitude indicates that interventions aimed at improving knowledge could benefit patients in more than one way. Interventions to equip patients to successfully manage their condition are urgently required

Calculation of ground- and excited-state energies of confined helium atom

We calculate the energies of ground and three low lying excited states of confined helium atom centered in an impenetrable spherical box. We perform the calculation by employing variational method with two-parameter variational forms for the correlated two-particle wave function. With just two variational parameters we get quite accurate results for both ground and excited state energies.Comment: 13 pages, No figur

Assessment of the physical activity, body mass index and energy intake of HIV-uninfected and HIV-infected women in Mangaung, Free State province

Published ArticleDeclining levels of physical activity at workplaces, during leisure time and when travelling, accompanied by increasing exposure to the mass media, are major determinants of the global obesity epidemic. This study aimed to assess physical activity, the body mass index (BMI) and energy intake of human immunodeficiency virus (HIV)-uninfected and HIV-infected black women in Mangaung. Method: A random sample of 500 black women was selected in Mangaung. Physical activity levels, dietary intake and BMI were determined in younger and older women, aged 25–34 and 35–44 years, respectively. Results: Of the 488 women who qualified for participation, 61% of the younger women and 38% of the older women were HIV-infected. Low physical activity levels were reported in most women, and more than 50% were overweight or obese. The BMI of HIV-infected younger women with low physical activity levels (24.9 kg/m2) was significantly lower than that of the HIV-uninfected younger women (27.2 kg/m2) (p-value 0.02). The energy intake of older HIV-infected women with low physical activity levels was significantly lower (10 090 kJ) than that of the older HIV-infected women in the normal to high physical activity category (14 519 kJ) (p-value 0.03). Conclusion: A more active lifestyle and energy-reduced diet that focuses on food quality could partially address BMI parameters in HIV-uninfected women. Safeguarding a lean BMI in HIV-infected women, by increasing physical activity levels while maintaining current energy intake, with an emphasis on healthy eating practices, could support quality of life

Sensitivity analyses of dense cloud chemical models

Because of new telescopes that will dramatically improve our knowledge of the interstellar medium, chemical models will have to be used to simulate the chemistry of many regions with diverse properties. To make these models more robust, it is important to understand their sensitivity to a variety of parameters. In this article, we report a study of the sensitivity of a chemical model of a cold dense core, with homogeneous and time-independent physical conditions, to variations in the following parameters: initial chemical inventory, gas temperature and density, cosmic-ray ionization rate, chemical reaction rate coefficients, and elemental abundances. From the results of the parameter variations, we can quantify the sensitivity of the model to each parameter as a function of time. Our results can be used in principle with observations to constrain some parameters for different cold clouds. We also attempted to use the Monte Carlo approach with all parameters varied collectively. Within the parameter ranges studied, the most critical parameters turn out to be the reaction rate coefficients at times up to 4e5 yr and elemental abundances at later times. At typical times of best agreement with observation, models are sensitive to both of these parameters. The models are less sensitive to other parameters such as the gas density and temperature. The improvement of models will require that the uncertainties in rate coefficients of important reactions be reduced. As the chemistry becomes better understood and more robust, it should be possible to use model sensitivities concerning other parameters, such as the elemental abundances and the cosmic ray ionization rate, to yield detailed information on cloud properties and history. Nevertheless, at the current stage, we cannot determine the best values of all the parameters simultaneously based on purely observational constraints.Comment: Accepted for publication in Astronomy & Astrophysic

Pathwise uniqueness of the squared Bessel and CIR processes with skew reflection on a deterministic time dependent curve

We investigate pathwise uniqueness for the squared Bessel and Cox-Ingersoll-Ross processes with additional reflection term that is multiplied by some real number strictly between minus one and one. The reflection term is the symmetric local time of the corresponding processes at a deterministic time dependent curve.Comment: Structured introduction and modified Section