Increasing Distributed Generation Penetration using Soft Normally-Open Points

This paper considers the effects of various voltage control solutions on facilitating an increase in allowable levels of distributed generation installation before voltage violations occur. In particular, the voltage control solution that is focused on is the implementation of `soft' normally-open points (SNOPs), a term which refers to power electronic devices installed in place of a normally-open point in a medium-voltage distribution network which allows for control of real and reactive power flows between each end point of its installation sites. While other benefits of SNOP installation are discussed, the intent of this paper is to determine whether SNOPs are a viable alternative to other voltage control strategies for this particular application. As such, the SNOPs ability to affect the voltage profile along feeders within a distribution system is focused on with other voltage control options used for comparative purposes. Results from studies on multiple network models with varying topologies are presented and a case study which considers economic benefits of increasing feasible DG penetration is also given

EEG findings of reduced neural synchronization during visual integration in schizophrenia

Schizophrenia patients exhibit well-documented visual processing deficits. One area of disruption is visual integration, the ability to form global objects from local elements. However, most studies of visual integration in schizophrenia have been conducted in the context of an active attention task, which may influence the findings. In this study we examined visual integration using electroencephalography (EEG) in a passive task to elucidate neural mechanisms associated with poor visual integration. Forty-six schizophrenia patients and 30 healthy controls had EEG recorded while passively viewing figures comprised of real, illusory, or no contours. We examined visual P100, N100, and P200 event-related potential (ERP) components, as well as neural synchronization in the gamma (30-60 Hz) band assessed by the EEG phase locking factor (PLF). The N100 was significantly larger to illusory vs. no contour, and illusory vs. real contour stimuli while the P200 was larger only to real vs. illusory stimuli; there were no significant interactions with group. Compared to controls, patients failed to show increased phase locking to illusory versus no contours between 40-60 Hz. Also, controls, but not patients, had larger PLF between 30-40 Hz when viewing real vs. illusory contours. Finally, the positive symptom factor of the BPRS was negatively correlated with PLF values between 40-60 Hz to illusory stimuli, and with PLF between 30-40 Hz to real contour stimuli. These results suggest that the pattern of results across visual processing conditions is similar in patients and controls. However, patients have deficits in neural synchronization in the gamma range during basic processing of illusory contours when attentional demand is limited

Can food vouchers improve nutrition and reduce health inequalities in low-income mothers and young children: A multi-method evaluation of the experiences of beneficiaries and practitioners of the Healthy Start programme in England

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background: Good nutrition is important during pregnancy, breastfeeding and early life to optimise the health of women and children. It is difficult for low-income families to prioritise spending on healthy food. Healthy Start is a targeted United Kingdom (UK) food subsidy programme that gives vouchers for fruit, vegetables, milk, and vitamins to low-income families. This paper reports an evaluation of Healthy Start from the perspectives of women and health practitioners. Methods. The multi-method study conducted in England in 2011/2012 included focus group discussions with 49 health practitioners, an online consultation with 620 health and social care practitioners, service managers, commissioners, and user and advocacy groups, and qualitative participatory workshops with 85 low-income women. Additional focus group discussions and telephone interviews included the views of 25 women who did not speak English and three women from Traveller communities. Results: Women reported that Healthy Start vouchers increased the quantity and range of fruit and vegetables they used and improved the quality of family diets, and established good habits for the future. Barriers to registration included complex eligibility criteria, inappropriate targeting of information about the programme by health practitioners and a general low level of awareness among families. Access to the programme was particularly challenging for women who did not speak English, had low literacy levels, were in low paid work or had fluctuating incomes. The potential impact was undermined by the rising price of food relative to voucher value. Access to registered retailers was problematic in rural areas, and there was low registration among smaller shops and market stalls, especially those serving culturally diverse communities. Conclusions: Our evaluation of the Healthy Start programme in England suggests that a food subsidy programme can provide an important nutritional safety net and potentially improve nutrition for pregnant women and young children living on low incomes. Factors that could compromise this impact include erosion of voucher value relative to the rising cost of food, lack of access to registered retailers and barriers to registering for the programme. Addressing these issues could inform the design and implementation of food subsidy programmes in high income countries. © 2014 McFadden et al.; licensee BioMed Central Ltd.The Policy Research Programme in the Department of Health, UK

Introduction to the AdS/CFT correspondence

This is a pedagogical introduction to the AdS/CFT correspondence, based on lectures delivered by the author at the third IDPASC school. Starting with the conceptual basis of the holographic dualities, the subject is developed emphasizing some concrete topics, which are discussed in detail. A very brief introduction to string theory is provided, containing the minimal ingredients to understand the origin of the AdS/CFT duality. Other topics covered are the holographic calculation of correlation functions, quark-antiquark potentials and transport coefficients.Comment: 64 pages, 12 figures;v2: minor improvements;v3: references adde

The variety, popularity and nutritional quality of tuck shop items available for sale to primary school learners in Pietermaritzburg, South Africa

Objectives: To determine the variety, popularity and nutritional quality of the food and beverages sold to primary school pupils. Method: A cross-sectional tuck shop survey. Nutritional analyses were conducted using the South African Medical Research Council Foodfinder 3 for Windows® software. Eleven mixed-race, well-resourced, government primary schools were studied in Pietermaritzburg, South Africa. Subjects included tuck shop managers from each school. Results: Savoury pies were the most popular lunch item for all learners for both breaks (n = 5, 45%, and n = 3, 27.3%), selling the most number of units (43) per day at eight schools (72.7%). Iced popsicles were sold at almost every school, ranked as the cheapest beverage, and also sold the most number of units (40.7). Healthy beverages sold included canned fruit juice and water, while healthy snacks consisted of dried fruit, fruit salad, bananas, yoghurt and health muffins. The average healthy snack contained almost half the kilojoules of the unhealthy counterpart (465 kJ vs. 806 kJ). Nutritional analyses of the healthy lunch options revealed total fat contents that exceeded the Dietary Reference Intake and South African recommended limits. Perceived barriers to stocking healthy items included cost and refrigeration restrictions. Conclusion: School tucks shops are selling products that encourage an unhealthy lifestyle, thereby promoting the obesity epidemic. Extensive consultation is required among dietitians, school principals and privatised tuck shop managers to overcome barriers to stocking healthy food in tuck shops.Keywords: school feeding, tuck shop, Pietermaritzburg, South Afric

Tuck-shop purchasing practices of Grade 4 learners in Pietermaritzburg and childhood overweight and obesity

Objectives: To determine the anthropometric characteristics of Grade 4 learners in relation to their tuck-shop purchasing practices.Design: A cross-sectional research design using a questionnaire that was administered to Grade 4 learners.Setting and subjects: Four well-resourced primary schools in Pietermaritzburg. The study included 311 Grade 4 learners.Outcome measures: Body mass index interpreted in relation to tuck-shop purchasing practices.Results: Fifty-six per cent of the sample were female (n = 173) and 44% were male (n = 138) learners. Twenty-seven per cent of the study sample was overweight (n = 83) and 27% was obese (n = 85). Eighty-six per cent of the learners (n = 266) made purchases from their school tuck shop. Twenty-two per cent did so at least three times per week (n = 58). Learners who bought from the tuck shop had a significantly higher body mass index compared to those who did not (p-value < 0.020). Learners who purchased from the tuck shop spent an average of R8.38 per day, a minimum of R1 and a maximum of R40 (± R5.39). The most popular reasons for visiting the tuck shop included: “This is my favourite thing to eat or drink” (66.5%, n = 177), and “I only have enough money to buy this item” (47%, n = 125). Conclusion: Poor tuck-shop purchasing practices may contribute to the development of childhood overweight and obesity in learners. Successful preventative strategies should focus on restricting the amount of unhealthy items that are available for sale, imposing spending limits and motivating learners to prioritise healthy food and beverage purchases.Keywords: childhood obesity, overweight, tuck-shop practices, body mass inde

Are South African women willing and able to apply the new Food-Based Dietary Guidelines? Lessons for nutrition educators

Background Consumer testing was a prime consideration in developing specific South African food-based dietary guidelines (FBDGs) which were nationally adopted in 2003. Objectives This study aimed to determine the consumer's ability to apply the FBDGs appropriately, in terms of identifying foods/drinks according to the FBDG food categories; perceived importance of and barriers to applying each FBDG; and planning a typical day's meals to reflect the FBDGs. Design A cross-sectional study of 333 women from different cultural and socio-economic backgrounds. Setting: KwaZulu-Natal, South Africa. Methods Data collection comprised focus-group discussions (n = 103) and structured individual interviews (n = 230). Results The identification of foods/drinks according to the FBDG food categories reflected a high level of comprehension by participants of these food categories. Participants from all study samples endorsed the importance of applying the FBDGs, predominantly for health reasons. Participants cited barriers to the application of the FBDGs as affordability, availability, household taste preferences, routine food-purchasing habits, time constraints, traditional/ habitual food-preparation methods, and persistent attitudes. Only three FBDGs were mentioned as difficult to apply, namely, “fruits/ vegetables”, “foods from animals” and “legumes”. Meal plans did reflect the FBDGs, illustrating the flexibility of their use across cultural and socio-economic differences. Conclusions Consumer testing of the FBDGs was mainly positive. The study has highlighted areas of confusion regarding certain concepts, terminology and misconceptions, and has identified barriers to application. These concerns can be addressed through the reformulation and retesting of certain dietary guidelines, and the provision of explanatory consumer information and health-worker training materials. SAJCN Vol. 21 (2) 2008: pp. 17-2

GMRT 610-MHz observations of the faint radio source population – and what these tell us about the higher radio-frequency sky

We present 610-MHz Giant Metrewave Radio Telescope observations of 0.84 deg$^{2}$ of the AMI001 field (centred on 00$^{h}$23$^{m}$10$^{s}$, +31°53′) with an rms noise of 18 μJy beam$^{-1}$ in the centre of the field. A total of 955 sources are detected, and 814 are included in the source count analysis. The source counts from these observations are consistent with previous work. We have used these data to study the spectral index distribution of a sample of sources selected at 15.7 GHz from the recent deep extension to the Tenth Cambridge (10C) survey. The median spectral index, α, (where S ∝ ν$^{−α}$) between 0.08<$\textit{S}$$_{15.7GHz}$/mJy<0.2 is 0.32 ± 0.14, showing that star-forming galaxies, which have much steeper spectra, are not contributing significantly to this population. This is in contrast to several models, but in agreement with the results from the 10C ultradeep source counts; the high-frequency sky therefore continues to be dominated by radio galaxies down to S$_{15.7GHz}$ = 0.1 mJy.The GMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research. IHW thanks the Science and Technologies Facilities Council for a studentship. IHW and MJJ acknowledge support from the Square Kilometre Array South Africa. IHW thanks the South African Astronomical Observatory, where some of this work was carried out