450 research outputs found

    The National Food Consumption Survey (NFCS): South Africa, 1999

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    Objective: The aim of the National Food Consumption Survey (NFCS) in South Africa was to determine the nutrient intakes and anthropometric status of children (1-9 years old), as well as factors that influence their dietary intake. Design: This was a cross-sectional survey of a nationally representative sample of all children aged 1-9 years in South Africa. A nationally representative sample with provincial representation was selected using 1996 Census information. Subjects: Of the 3120 children who were originally sampled data were obtained from 2894, a response rate of 93%. Methods: The sociodemographic status of each household was assessed by a questionnaire. Dietary intake was assessed by means of a 24-hour recall and a food-frequency questionnaire from the caregivers of the children. Food purchasing practices were determined by means of a food procurement questionnaire. Hunger was assessed by a modified hunger scale questionnaire. Nutritional status was determined by means of anthropometric measurements: height, weight, head circumference and arm circumference. Results: At the national level, stunting (height-for-age below minus two standard deviations (< -2SD) from the reference median) was by far the most common nutritional disorder, affecting nearly one in five children. The children least affected (17%) were those living in urban areas. Even with regard to the latter, however, children living in informal urban areas were more severely affected (20%) compared with those living in formal urban areas (16%). A similar pattern emerged for the prevalence of underweight (weight-for-age < -2SD), with one in 10 children being affected at the national level. Furthermore, one in 10 (13%) and one in four (26%) children aged 1-3 years had an energy intake less than half and less than two-thirds of their daily energy needs, respectively. For South African children as a whole, the intakes of energy, calcium, iron, zinc, selenium, vitamins A, D, C and E, riboflavin, niacin, vitamin B6 and folic acid were below two-thirds of the Recommended Dietary Allowances. At the national level, data from the 24-hour recalls indicated that the most commonly consumed food items were maize, sugar, tea, whole milk and brown bread. For South African children overall, one in two households (52%) experienced hunger, one in four (23%) were at risk of hunger and only one in four households (25%) appeared food-secure. Conclusion: The NFCS indicated that a large majority of households were food-insecure and that energy deficit and micronutrient deficiencies were common, resulting in a high prevalence of stunting. These results were used as motivation for the introduction of mandatory fortification in South Africa. © The Authors 2005.Conference Pape

    In vitro activity of a new 'higher-lactam' antibacterial agent LY 193239

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    In vitro activity ofthe new bicyclic pyrazolidinone LY 193239 (Eli Lilly) was evaluated against 52 clinical isolates of Haemophilus influenzae (4 were β-lactamase producers), 32 Enterococcus faecalis, 14 Neisseria gonorrhoeae (1 β-lactamasepositive) and 19 Neisseria meningitidis. Activity was best against Neisseria spp. and H. influenzae, including penicillinase- producing strains. Results of the time-kill study against a non-enzyme-mediated penicillin resistant strain of N. meningitidis indicate that exposure to an antibacterial concentration four times the minimal inhibitory concentration was bactericidal. E. faecalis was insensitive

    “Have milk, maas or yoghurt every day”: a food-based dietary guideline for South Africa

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    A national working group recently reached consensus that a guideline  message for milk consumption should form part of the set of revised food-based dietary guidelines (FBDGs) for South Africa. The message was formulated as: “Have milk, maas or yoghurt every day”. This paper provides scientific support for this FBDG, based on the nutrition and healthprofile of South Africans; addresses concerns about possible detrimental effects of milk consumption, such as lactose intolerance, saturated fat and trans-fat content, milk allergies and dental caries in children; and  identifies barriers to increased consumption. The guideline refers to milk, maas and yoghurt, and not all dairy products. This is based on the nutrient contribution of these products to a healthy diet. Milk (and some dairy products) has a low sodium-to-potassium ratio, as well as bioactive peptides, which may protect against the development of noncommunicable diseases. There is some evidence that the calcium in milk and dairy plays an important role in the regulation of body weight and bone mineral content in children. Available data show that milk and calcium intake in South Africans is low. Identified barriers include perceptions about lactose intolerance, taste, price, lack of knowledge on the nutritive value of milk and milk products, and possibly cultural taboos. As a result, increasing the consumption of milk, maas and yoghurt of South Africans will require active, multifaceted and multilevel promotion

    Unidentified Galactic High-Energy Sources as Ancient Pulsar Wind Nebulae in the light of new high energy observations and the new code

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    In a Pulsar Wind Nebula (PWN), the lifetime of inverse Compton (IC) emitting electrons exceeds the lifetime of its progenitor pulsar (as well as its shell-type remnant), but it also exceeds the age of those that emit via synchrotron radiation. Therefore, during its evolution, the PWN can remain bright in IC so that its GeV-TeV gamma-ray flux remains high for timescales much larger (for 10^5 - 10^6 yrs) than the pulsar lifetime and the X-ray PWN lifetime. In this scenario, the magnetic field in the cavity induced by the wind of the progenitor star plays a crucial role. This scenario is in line with the discovery of several unidentified or "dark" sources in the TeV gamma-ray band without X-ray counterparts; and it is also finding confirmation in the recent discoveries at GeV gamma rays. Moreover, these consequences could be also important for reinterpreting the detection of starburst galaxies in the TeV gamma-ray band when considering a leptonic origin of the gamma-ray signal. Both theoretical aspects and their observational proofs will be discussed, as well as the first results of our new modeling code.Comment: Proceedings of the 5th International Symposium on High-Energy Gamma-Ray Astronomy (Gamma2012

    Enhancing CLIP with GPT-4: Harnessing Visual Descriptions as Prompts

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    Contrastive pretrained large Vision-Language Models (VLMs) like CLIP have revolutionized visual representation learning by providing good performance on downstream datasets. VLMs are 0-shot adapted to a downstream dataset by designing prompts that are relevant to the dataset. Such prompt engineering makes use of domain expertise and a validation dataset. Meanwhile, recent developments in generative pretrained models like GPT-4 mean they can be used as advanced internet search tools. They can also be manipulated to provide visual information in any structure. In this work, we show that GPT-4 can be used to generate text that is visually descriptive and how this can be used to adapt CLIP to downstream tasks. We show considerable improvements in 0-shot transfer accuracy on specialized fine-grained datasets like EuroSAT (~7%), DTD (~7%), SUN397 (~4.6%), and CUB (~3.3%) when compared to CLIP's default prompt. We also design a simple few-shot adapter that learns to choose the best possible sentences to construct generalizable classifiers that outperform the recently proposed CoCoOP by ~2% on average and by over 4% on 4 specialized fine-grained datasets. We will release the code, prompts, and auxiliary text dataset upon acceptance.Comment: 10 pages, Pre-prin

    Numerical simulations of composite supernova remnants for small σ\sigma pulsar wind nebulae

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    Composite supernova remnants consist of a pulsar wind nebula located inside a shell-type remnant. The presence of a shell has implications on the evolution of the nebula, although the converse is generally not true. The purpose of this paper is two-fold. The first aim is to determine the effect of the pulsar's initial luminosity and spin-down rate, the supernova ejecta mass, and density of the interstellar medium on the evolution of a spherically-symmetric, composite supernova remnant expanding into a homogeneous medium. The second aim is to investigate the evolution of the magnetic field in the pulsar wind nebula when the the composite remnant expands into a non-uniform interstellar medium. The Euler conservation equations for inviscid flow, together with the magnetohydrodynamic induction law in the kinematic limit, are solved numerically for a number of scenarios where the ratio of magnetic to particle energy is σ<0.01\sigma < 0.01. The simulations in the first part of the paper is solved in a one-dimensional configuration. In the second part of the paper, the effect of an inhomogeneous medium on the evolution is studied using a two-dimensional, axis-symmetric configuration

    An exploratory study of Heads of Departments' responses to student calls for decolonised higher education

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    Central to the tumultuous student protests of 2015 and 2016 was an urgent call for the decolonisation of South African universities. Existing curricula, including teaching and assessment practices, as well as institutional cultures and structures were challenged. Against this backdrop, in this article we focus on the academic leadership role of Heads of Departments (HoDs) at Rhodes University. In this small-scale project we interrogate how HoDs conceptualised their roles in this uncertain and complex context. From the data analysis a number of tensions emerged in the ways in which they articulated and enacted their roles. The findings indicate that the protests have contributed to the increasing complexity of the role of an HoD. Issues raised during the protests catalysed HoDs at Rhodes University, some for the first time, into considering the implications of the decolonising call from students and into exercising stronger transformative leadership roles
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