Analytical application of proton-induced prompt photon specrometry

Bibliography: p. 353-356.Prompt gamma-rays emitted tinder bombardment with 3.5 to 6.0MeV protons from the 77 stable non-gaseous elements were evaluated for analytical application. The compilation included the yields of about 2200 gamma-rays and their detection limit for analysis. Because the data were measured under identical experimental conditions, the relative values may be generally applicable. For each element, the gamma-ray spectrum and the numerical data are presented in tables listing identified gamma-rays with yields and detection limits for Ep = 4.5 MeV, the gamma yields as a function of proton energy for the most intense gamma-prays, and, the polynomial coefficients of the function relating the detection limit to the bombarding energy. An Atlas of Spectra and a Catalogue of gamma-rays summarised the data

Flamingo predation impacts on benthic communities: effects of spatial gradients

Includes bibliographical references.Biological disturbances on marine soft sediment ecosystems have been well researched. However, little attention has been paid to the potential ecological role that iconic shore bird predators may have on marine ecosystems. This paper tests the effects of spatial gradients on Greater Flamingo (Phoenicopterus ruber) predation impacts on the benthic macrofaunal community structure in an intertidal sandflat ecosystem in South Africa. P. ruber is a benthic filter-feeder known to feed on benthic dwelling invertebrates through pit formation, where deep sediments are stirred up by trampling their feet. Macrofaunal community structure between flamingo pit foraging structures and adjacent non-foraged sediments (controls) yielded insignificant spatial differences. However, subtle positive and negative effects of flamingo predation on macrofaunal abundance were noted at specific sites. Flamingos in this study were not targeting a specific prey group. Thus of the 19 macrofaunal prey items identified, none were significantly impacted across treatments, except for an unidentified polychaete. However, this was once again site specific. The results suggested this polychaete is generally abundant within the area sampled. Furthermore, its distribution is perhaps affected by the level of intensity employed in pit-foraging, rather than being preyed upon. Greater polychaete abundance in pits relative to controls may be attributed to vigorous flamingo feeding efforts. Pit foraging appears to be an expensive strategy to employ, but the energy investment may be reduced through the use of sophisticated sensory organs to detect accessible prey deep within the sediment. Overall, the study has shown that the impact of flamingo predation on a spatial gradient is small and site specific. However, the study highlights the need for further research on quantifying the ecological role flamingos play as predators on marine ecosystems

Flamingo foraging plasticity: ecological drivers and impacts

The consequences of predation have become a central focus of marine ecological research. Numerous studies have emphasized the importance of apex predators in structuring assemblages at various organisational levels and in determining how ecosystems function. However, less appreciated currently is the fact that predators display multiple foraging behaviours, thereby allowing them to overcome problems associated with unpredictability of food resources in space and time. The primary goal of this dissertation is to contribute to growing understanding of the ecological causes and consequences of foraging plasticity displayed by Greater Flamingo Phoenicopterus ruber roseus in intertidal sandflat ecosystems in Langebaan Lagoon, South Africa. P. roseus feeds by either (1) creating pits, which involves flamingos stirring up deep sediments with their feet or (2) creating channels, in which their inverted bills are swept from side-to-side on the sediment surface. The first objective of the study was to quantify the ecological drivers of decisions made by flamingos to feed, and to implement either pit- or channel-foraging strategies. The latter was achieved through RandomForest modelling techniques that identified the prominent ecological drivers from a suite of biotic and abiotic variables. Results indicate that biotic variables, i.e. those associated with flamingo prey assemblages, were key in driving choices made by flamingos to forage and to implement either pit- or channel-foraging strategies. The second aim of this dissertation was to quantify the repercussions of the two different foraging behaviours on benthic assemblages. Comparisons of benthic assemblages in flamingo foraging structures (pits and channels) with adjacent non-foraged sediments (controls) indicated differential effects of both flamingo foraging methods on benthic communities, with channel-foraging eliciting a greater negative impact compared to pit-foraging, for which impacts were negligible. Abundance of macrofauna and surface-dwelling taxa such as micro-algae and the amphipod Urothoe grimaldii were all negatively impacted by channel-foraging. Sizes of channels constructed by flamingos were inversely related to their impacts, with impacts on macrofaunal abundance being greater in smaller channels. Overall, this study has shed light on the differential effects of foraging plasticity on prey assemblages and its importance in enhancing spatio-temporal heterogeneity in intertidal sandflats. The study also emphasizes the need to incorporate foraging plasticity into current thinking and conceptual models of predation in marine soft sediments, in order to appreciate the full spectrum of predation effects on assemblages

Out-of-hospital assessment and management of rape survivors by pre-hospital emergency care providers in the Western Cape

South African incidence of rape ranks amongst the highest worldwide. No direct policy exists for the emergency care provider management of rape victims in the pre-hospital setting. The pre-hospital exposure to rape cases is unknown as its health information system is not gender-based violence sensitive. In the absence of a clearly defined protocol, indiscretion in the emergency care treatment of rape victims remains undocumented. As a particularly vulnerable group globally, victims of rape are deserving of focused intervention. A qualitative, descriptive approach guided the research in which nine semi-structured voluntary interviews were held with emergency care providers, forensic medical practitioners and emergency consultants. Through a critical theory lens thematic content analysis was employed. University of Cape Town ethics approval was attained. The study found that pre-hospital providers lack knowledge and skills of rape victim identification and management but are desirous of evidence-informed guidelines for treatment and referral in a multidisciplinary approach. Educational and policy deficiencies are documented. The recommendations support a community of practice that is mutually inclusive of specialist rape-care centres, emergency department and pre-hospital providers in the interest of forensic emergency medicine. Due regard must be had for needs of practitioners at risk of vicarious traumatization from sexual assault management. Transformative curricula and responsive clinical guidelines are likely to redress any complicity of the health sector non-response to rape/sexual assault. This study is likely to benefit emergency care regulators, educators and researchers whose professional interest is to promote responsivity of the health system to rape

Stimulant use among prehospital emergency care personnel in Gauteng Province, South Africa

Background. Emergency medical service (EMS) personnel are exposed to high levels of psychological, physical and emotional stressors. There has been an increase in stimulant use among healthcare professionals worldwide. There is a paucity of data pertaining to the use of stimulant products among EMS personnel in South Africa (SA).Objectives. To determine the prevalence of and other aspects pertaining to use of stimulant products among EMS personnel in Gauteng Province, SA.Methods. A prospective cross-sectional study using a questionnaire-based model was used to survey EMS personnel in Gauteng.Results. Of the 315 respondents who completed the questionnaire, 310 (98.4%) reported use of stimulant products, 295 (93.7%) consumed tea/coffee, 187 (59.4%) consumed commercial energy drinks, 60 (19.0%) used caffeinated energy-enhancing tablets, 14 (4.4%) used non-caffeinated prescription stimulant medications, 50 (15.9%) used illicit drugs, 134 (42.5%) exceeded the recommended daily allowance (RDA) of caffeine, 201 (63.8%) exceeded the RDA of sugar, 231 (73.3%) experienced difficulty remaining awake during a shift, 148 (47.8%) used stimulants off shift, and 71 (22.5%) experienced insomnia. Common reasons for use of stimulants were enjoyment (n=218; 69.2%), to stay awake (n=125; 39.7%) and improvement of physical and mental performance (n=94; 29.8%).Conclusions. The high prevalence of stimulant use among respondents is a cause for concern. Strategies to address it should be aimed at promoting awareness and education, improving working conditions, enhancing support structures, and regulating the stimulant content of commercial products.

Which method is best for the induction of labour?: A systematic review, network meta-analysis and cost-effectiveness analysis

Background: More than 150,000 pregnant women in England and Wales have their labour induced each year. Multiple pharmacological, mechanical and complementary methods are available to induce labour. Objective: To assess the relative effectiveness, safety and cost-effectiveness of labour induction methods and, data permitting, effects in different clinical subgroups. Methods: We carried out a systematic review using Cochrane methods. The Cochrane Pregnancy and Childbirth Group’s Trials Register was searched (March 2014). This contains over 22,000 reports of controlled trials (published from 1923 onwards) retrieved from weekly searches of OVID MEDLINE (1966 to current); Cochrane Central Register of Controlled Trials (The Cochrane Library); EMBASE (1982 to current); Cumulative Index to Nursing and Allied Health Literature (1984 to current); ClinicalTrials.gov; the World Health Organization International Clinical Trials Registry Portal; and hand-searching of relevant conference proceedings and journals. We included randomised controlled trials examining interventions to induce labour compared with placebo, no treatment or other interventions in women eligible for third-trimester induction. We included outcomes relating to efficacy, safety and acceptability to women. In addition, for the economic analysis we searched the Database of Abstracts of Reviews of Effects, and Economic Evaluations Databases, NHS Economic Evaluation Database and the Health Technology Assessment database. We carried out a network meta-analysis (NMA) using all of the available evidence, both direct and indirect, to produce estimates of the relative effects of each treatment compared with others in a network. We developed a de novo decision tree model to estimate the cost-effectiveness of various methods. The costs included were the intervention and other hospital costs incurred (price year 2012–13). We reviewed the literature to identify preference-based utilities for the health-related outcomes in the model. We calculated incremental cost-effectiveness ratios, expected costs, utilities and net benefit. We represent uncertainty in the optimal intervention using cost-effectiveness acceptability curves. Results: We identified 1190 studies; 611 were eligible for inclusion. The interventions most likely to achieve vaginal delivery (VD) within 24 hours were intravenous oxytocin with amniotomy [posterior rank 2; 95% credible intervals (CrIs) 1 to 9] and higher-dose (≥ 50 μg) vaginal misoprostol (rank 3; 95% CrI 1 to 6). Compared with placebo, several treatments reduced the odds of caesarean section, but we observed considerable uncertainty in treatment rankings. For uterine hyperstimulation, double-balloon catheter had the highest probability of being among the best three treatments, whereas vaginal misoprostol (≥ 50 μg) was most likely to increase the odds of excessive uterine activity. For other safety outcomes there were insufficient data or there was too much uncertainty to identify which treatments performed ‘best’. Few studies collected information on women’s views. Owing to incomplete reporting of the VD within 24 hours outcome, the cost-effectiveness analysis could compare only 20 interventions. The analysis suggested that most interventions have similar utility and differ mainly in cost. With a caveat of considerable uncertainty, titrated (low-dose) misoprostol solution and buccal/sublingual misoprostol had the highest likelihood of being cost-effective. Limitations: There was considerable uncertainty in findings and there were insufficient data for some planned subgroup analyses. Conclusions: Overall, misoprostol and oxytocin with amniotomy (for women with favourable cervix) is more successful than other agents in achieving VD within 24 hours. The ranking according to safety of different methods was less clear. The cost-effectiveness analysis suggested that titrated (low-dose) oral misoprostol solution resulted in the highest utility, whereas buccal/sublingual misoprostol had the lowest cost. There was a high degree of uncertainty as to the most cost-effective intervention

The profile of the overdose patient admitted to a tertiary hospital in Gauteng

A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, in partial fulfillment of the requirements for the degree of Master of Medicine in Emergency Medicine. Johannesburg, 2016Background Overdose is an important health care problem, a subject under-researched in South Africa. The aims of this study are to investigate the demographics, to identify common substances and to ascertain the burden of disease at a tertiary hospital in Gauteng. Data can be used to reduce morbidity, mortality and the substantial costs to health care services related to overdose. Materials and methods A retrospective, observational study based on hospital records (16 weeks). The analysis was purely descriptive. Categorical data were compared using the Chisquare test. P value < 0.05 was considered significant. Results Of the total of 176 records with a primary diagnosis of overdose, 133 were included. The frequency of overdose was found to be 1.1 cases per day. Females accounted for 64.7%, 82.8% were single, 85% were Black, 78.9% were unemployed and 54.2% resided in poor socio-economic areas. Overdose was highest in the 20-29 years (55.6%) age group with a mean age of 28.1 years. Overdose was intentional in 91% and 12% of the subjects had overdosed previously. A previous medical history was found in 22.6% and HIV was prevalent in 66.7%. The most common substance groups were analgesics (32.3%), pesticides (21.1%), anxiolytics (11.3%), household chemicals (10.5%), vitamins (8.3%), antibiotics (7.5%) and anti-retrovirals (ARV’s) (5.3%). In 99.3% the substance was ingested orally and in 23.3% there was concurrent alcohol consumption. Common precipitating factors were relationship problems, depression, domestic problems and financial. The median delay to hospital presentation was 3.5 hours and patients tended to present during the afternoon and the night with a significant association between time of presentation and age group (p=0.043). An antidote was employed in 35.3% and in 97% of cases, symptomatic treatment was by far the most common. No patients were discharged directly from the ED and in 42.1% the median length of hospital stay was 2 days and a case fatality rate of 1.5%. Conclusion The introduction of management protocols is of uttermost importance. Awareness, education and regulations will form part of strategies for the prevention of overdose.MT201