9 research outputs found
Factors that determine the corporate image of South African fast food restaurants
Current operating practices of small businesses indicate that more time is devoted to the cosmetic side of corporate identity than managing service delivery. The main argument pursued in this paper is based on the view that both visual and behavioural corporate identity cues create impressions in the minds of corporate publics to form an overall corporate image. A set of bipolar adjectives was therefore used to test various visual, behavioural and core product elements of restaurant corporate image. A key finding was made that the joint customer service and employee dimension, was rated as the most important factor in the choice of fast food restaurants, which confirms that corporate image is created by visual and behavioural identity
Status report of the NAC particle therapy programme
The 200 MeV cyclotron facility at the National Accelerator Centre has been operational since 1987. Between September 1988 and December 1997 a total of 973 patients (26,916 fields) had been treated on the 66 MeV p+Be isocentric neutron therapy system. Patients are currently being treated according to several protocols, including tumors of the head and neck, salivary gland and breast and soft tissue sarcomas, uterine sarcomas and paranasal sinuses. A multiblade post-collimator trimmer has recently being installed. This device provides improved neutron beam shaping capability. Between September 1993 and December 1997 a total of 243 patients (4008 fields) had been treated (mainly intracranial stereotactic irradiations) on the fixed horizontal 200 MeV proton therapy facility. The facility incorporates an innovative automatic patient positioning system. Two new fixed beam lines for proton therapy are presently being designed (horizontal and 30°to the vertical) for an existing unused treatment vault. Spot scanning systems will be developed for both beam lines.Conference Pape
The NAC proton treatment planning system
A three-dimensional proton treatment planning system called PROXELPLAN has been used at the National Accelerator Centre (NAC) since October 1994. This system is entirely based on the VOXELPLAN planning system, developed at the Deutches Krebsforschungszentrum (DKFZ), Heidelberg, Germany. The VOXELPLAN system provides the treatment planning infrastructure while the proton dose distributions are calculated using a software module that was initially developed at the Royal Marsden Hospital, UK. The proton module has been extensively modified and refined. It uses a rayline-tracing algorithm which is suitable for planning current treatments but is not sufficiently dynamic to accommodate the use of compensators. A sophisticated pencil beam algorithm is currently under development.Conference Pape
Proton relative biological effectiveness (RBE) for survival in mice after thoracic irradiation with fractionated doses
Purpose: This study aims at providing relative biological effectiveness (RBE) data under reference conditions accounting for the determination of the 'clinical RBE' of protons.Methods and Materials: RBE (ref. 60Co γ-rays) of the 200 MeV clinical proton beam produced at the National Accelerator Centre (South Africa) was determined for lung tolerance assessed by survival after selective irradiation of the thorax in mice. Irradiations were performed in 1, 3, or 10 fractions separated by 12 h. Proton irradiations were performed at the middle of a 7-cm spread out Bragg peak (SOBP). Control γ irradiations were randomized with proton irradiations and performed simultaneously. A total of 1008 mice was used, of which 96 were assessed for histopathology.Results: RBEs derived from LD50 ratios were found not to vary significantly with fractionation (corresponding dose range, ~2-20 Gy). They, however, tend to increase with time and reach (mean of the RBEs for 1, 3 and 10 fractions) 1.00, 1.08, 1.14, and 1.25 for LD50 at 180, 210, 240, and 270 days, respectively (confidence interval approximately 20%). α/β ratios for protons and γ are very similar and average 2.3 (0.6-4.8) for the different endpoints. Additional irradiations in 10 fractions at the end of the SOBP were found slightly more effective (~6%) than at the middle of the SOBP. A control experiment for intestinal crypt regeneration in mice was randomized with the lung experiment and yielded an RBE of 1.14 ± 0.03, i.e., the same value as obtained previously, which vouches for the reliability of the experimental procedure.Conclusion: There is no need to raise the clinical RBE of protons in consideration of the late tolerance of healthy tissues in the extent that RBE for lung tolerance was found not to vary with fractionation nor to differ significantly from those of the majority of early- and late-responding tissues. Copyright (C) 2000 Elsevier Science Inc.Articl
RBE of the 200-MeV proton beam produced at the National Accelerator Centre of Faure (RSA) for late lung tolerance in mice after single - and fractionated-irradiation (preliminary results)
Serum erythropoietin levels in anaemic patients with advanced human immunodeficiency virus infection
Oral Coenzyme Q10 supplementation leads to better preservation of kidney function in steroid-resistant nephrotic syndrome due to primary Coenzyme Q10 deficiency.
Primary Coenzyme Q10 (CoQ10) deficiency is an ultra-rare disorder caused by defects in genes involved in CoQ10 biosynthesis leading to multidrug-resistant nephrotic syndrome as the hallmark kidney manifestation. Promising early results have been reported anecdotally with oral CoQ10 supplementation. However, the long-term efficacy and optimal prescription remain to be established. In a global effort, we collected and analyzed information from 116 patients who received CoQ10 supplements for primary CoQ10 deficiency due to biallelic pathogenic variants in either the COQ2, COQ6 or COQ8B genes. Median duration of follow up on treatment was two years. The effect of treatment on proteinuria was assessed, and kidney survival was analyzed in 41 patients younger than 18 years with chronic kidney disease stage 1-4 at the start of treatment compared with that of an untreated cohort matched by genotype, age, kidney function, and proteinuria. CoQ10 supplementation was associated with a substantial and significant sustained reduction of proteinuria by 88% at 12 months. Complete remission of proteinuria was more frequently observed in COQ6 disease. CoQ10 supplementation led to significantly better preservation of kidney function (5-year kidney failure-free survival 62% vs. 19%) with an improvement in general condition and neurological manifestations. Side effects of treatment were uncommon and mild. Thus, our findings indicate that all patients diagnosed with primary CoQ10 deficiency should receive early and life-long CoQ10 supplementation to decelerate the progression of kidney disease and prevent further damage to other organs