797 research outputs found
Reconsidering management for otitis media with effusion in children
Otitis media is the most commonly diagnosed illness apart from the common cold and treatment by insertion of tympanoplasty tubes is the most frequent operation in children beyond the neonatal period. Approximately nine in every ten children have had at least one episode by the age of two years and figures for South Africa may even be higher. Recent research findings have led to a more conservative approach to treatment of otitis media with effusion as opposed to previous recommendations for prompt insertion of tympanostomy tubes to avoid suspected developmental delays due to the mild conductive hearing loss. A large scale longitudinal clinical trial has demonstrated that prompt versus delayed insertion of tympanostomy tubes does not affect developmental outcomes and therefore a conservative approach of monitoring the condition and hearing status alongside speech and language development is recommended without the use of medication as routine management. These recommendations may ultimately result in significant healthcare savings for South Africa but must be implemented within a collaborative team approach to ensure developmental outcomes are not compromised due to poor surveillance.
South African Family Practice Vol. 49 (7) 2007: pp.
The Fermat-Torricelli problem in normed planes and spaces
We investigate the Fermat-Torricelli problem in d-dimensional real normed
spaces or Minkowski spaces, mainly for d=2. Our approach is to study the
Fermat-Torricelli locus in a geometric way. We present many new results, as
well as give an exposition of known results that are scattered in various
sources, with proofs for some of them. Together, these results can be
considered to be a minitheory of the Fermat-Torricelli problem in Minkowski
spaces and especially in Minkowski planes. This demonstrates that substantial
results about locational problems valid for all norms can be found using a
geometric approach
A new approach to evaluate gamma-ray measurements
Misunderstandings about the term random samples its implications may easily arise. Conditions under which the phases, obtained from arrival times, do not form a random sample and the dangers involved are discussed. Watson's U sup 2 test for uniformity is recommended for light curves with duty cycles larger than 10%. Under certain conditions, non-parametric density estimation may be used to determine estimates of the true light curve and its parameters
Ethical demand and first year civil engineering study : applying virtue ethics
Abstract: Incidents within the civil engineering profession (structural collapses, collusion, and the like) draw attention to the need for ethical conduct on the part of civil engineering practitioners. This paper explores ethical action in first-year civil engineering study. This is done to discuss the role of universities in the development of civil engineering graduates with a critical awareness of the need for ethical action. The paperusesaparticularapproachtovirtueethicstotheorizefirst-yearstudentactionsduringapracticalexerciseinconcretemixproportioning. Three aspects of ethical action emerged from observation of the students’ completion of this practicum: corner-cutting, erroneous reporting, and misrepresentation of knowledge and ability. The paper argues that ethical behavior should be nurtured and discussed throughout the undergraduate degree, so that students are more likely to practice ethical behavior after graduation. There is thus opportunity to better integrateconsiderationofethicalresponsibilityintotheundergraduatecurriculum, and to shift the focus of higher education away from external goods to the good of the profession and the communities it serves
Exploring the alignment of first-year summative assessments with Bloom’s Taxonomy: A longitudinal study
The correlation between the level of difficulty of assessments, Bloom’s Taxonomy as well as pass rates of courses has been a seriously under-researched area in South Africa. In this study, we proposed the revised Bloom’s taxonomy level of difficulty index, before we examined 112 first-year 2017‒2019 final and supplementary assessment papers from the Economic and Management Sciences Faculty of a university in Western Cape.
The descriptive statistics showed that these assessment papers are different in terms of duration, total marks, type of questions asked as well as pass rates. It was also found that these first-year summative assessments asked questions mainly at levels two (understand) and three (apply) of the revised Bloom’s Taxonomy. In addition, the correlation and econometric analysis did not find a strong correlation between the level of difficulty index and pass rates. Nonetheless, the above-mentioned results need to be interpreted with great caution, because strictly speaking, one should also control for differences in other characteristics (e.g., students’ personal characteristics, school characteristics and lecture attendance).
To conclude, there is no explicit national policy that guides higher education institutions (HEIs) on how to use Bloom’s or any other taxonomy to assess students at the appropriate National Qualifications Framework (NQF) level. Hence, our findings suggest that there is a need for a national assessment policy framework to guide HEIs on how to assess undergraduate students at different cognitive levels as required by the NQF
Protection of Personal Information Act 2013 and data protection for health research in South Africa
• The Protection of Personal Information Act (POPIA) [No.4 of 2013] is the first comprehensive data protection regulation to be passed in South Africa and it gives effect to the right to informational privacy derived from the constitutional right to privacy.
• It is due to come into force in 2020, and seeks to regulate the processing of personal information in South Africa, regulate the flow of personal information across South Africa’s borders, and ensure that any limitations on the right to privacy are justified and aimed at protecting other important rights and interests.
• Although it was not drafted with health research in mind, POPIA will have an impact on the sharing of health data for research, in particular biorepositories.
• It is now timely to consider the impact of POPIA on biorepositories, and the necessary changes to their access and sharing arrangements prior to POPIA coming into force
Transplantation for diabetic nephropathy at Groote Schuur Hospital
Over a period of 6 years, 9 patients with diabetic nephropathy received renal allografts at Groote Schuur Hospital. This low figure represents 2,8% of the total number of renal transplants done at our institution, and is evidence of concern about the apparent poor results of transplantation in these patients. After 2 years, patients and graft survival rates in diabetics were 87% and 62% respectively. Vascular disease was a major problem. Six patients developed limb gangrene, and symptomatic coronary and cerebrovascular disease developed in 2 patients. Infections were common and included wound sepsis, cellulitis, candidiasis and urinary tract infections. Diabetes was poorly controlled after transplantation in 5 patients. Proliferative retinopathy was present in 6 patients but remained stable after transplantation.Despite very strict selection criteria, the results of renal transplantation in diabetic patients remain poor. Better treatment strategies are needed to justify acceptance of these patients for transplantation
Integrating the landscape epidemiology and genetics of RNA viruses: rabies in domestic dogs as a model
Landscape epidemiology and landscape genetics combine advances in molecular techniques, spatial analyses and epidemiological models to generate a more real-world understanding of infectious disease dynamics and provide powerful new tools for the study of RNA viruses. Using dog rabies as a model we have identified how key questions regarding viral spread and persistence can be addressed using a combination of these techniques. In contrast to wildlife rabies, investigations into the landscape epidemiology of domestic dog rabies requires more detailed assessment of the role of humans in disease spread, including the incorporation of anthropogenic landscape features, human movements and socio-cultural factors into spatial models. In particular, identifying and quantifying the influence of anthropogenic features on pathogen spread and measuring the permeability of dispersal barriers are important considerations for planning control strategies, and may differ according to cultural, social and geographical variation across countries or continents. Challenges for dog rabies research include the development of metapopulation models and transmission networks using genetic information to uncover potential source/sink dynamics and identify the main routes of viral dissemination. Information generated from a landscape genetics approach will facilitate spatially strategic control programmes that accommodate for heterogeneities in the landscape and therefore utilise resources in the most cost-effective way. This can include the efficient placement of vaccine barriers, surveillance points and adaptive management for large-scale control programmes
Movements, nesting and the effects of pollution on the Nile crocodile (Crocodylus niloticus) in the Olifants River, Kruger National Park.
Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1999.A pilot study was launched in 1993 to determine the movements of crocodiles in the Olifants River in
Kruger National Park (KNP). This turned into a research project in 1994 and lasted for five years until
1998. The objectives of the study were to determine movement, study nesting preferences and to
investigate the possible effects of metal pollution in crocodiles.
The movements of the total population were studied by doing regular foot counts, four times per annum.
The basis for movement was found on the principle that a change in numbers signified movement. Foot
counts were supported by spot counts at three different locations in the study area at 14 day intervals.
The foot counts were done along a pre-determined route, followed with every count, and this resulted in
data indicating a definite change in numbers at certain times of the year. A comparison was made
between the movements of crocodiles in large bodies of open water (lakes & estuaries), a so called
"closed" system and the Olifants River or "open" system. There was a movement of the population
during August of every year, followed by another one in December/Jan and yet another in May. The
largest movement, in August, co-coincided with the prelude to mating and ultimately nesting.
The spot counts indicated that there was a smaller and probably localized movement during May and
December of each year. This corresponds to nesting behaviour and the flood status of the river. All
indications are that major movements took place during periods of high flow and thus during the rain
season (Sept - Feb). A major flood was experienced during February 1996 which changed the geomorphology of the river.
In addition to the foot and spot counts, eleven large adult crocodiles were fitted with radio transmitters to
monitor their movements for a period of one year (1997 -1998). The results indicated that movements
over large distances occurred. The longest distance covered was in access of 36 km. Some individuals
returned to the location of origin, thus completing a round trip from their point of departure. The majority
of crocodiles fitted with transmitters left the protection of KNP, spent time in neighbouring Mozambique and some returned to Kruger after an average period of three months. Indications are that there is a lack
of territorial dominance amongst large individuals at certain times of the year, allowing for less restricted
movement up and down the river. A difference was found between the movements of crocodiles in the
Olifants River as opposed to a large body of water eg. a lake or estuary.
The second objective was to collect data on nesting preference, nest content and egg dimensions. A
total of seven parameters were measured including slope, distance to water, height above water, soil
type, vegetation, exposure to direct sunlight and the size of the female. Besides these parameters, a
comparison was made between egg size, mass and length and the correlation with female size. The
results indicated that egg mass and length increased with an increase in female size. The average
clutch size was 34 eggs. A difference was found between two nesting years (1997 and 1998) with the
larger females nesting in 1998 (egg mass 122.7g). A higher rainfall was measured for 1998, leading to
the conclusion that smaller females nested during dryer years. The larger females, because of physical
abilities, dug deeper nests ,36 cm in 1998 as opposed to 25 cm in 1997. No difference was found
between nesting habits elsewhere in Africa and that in the Olifants River.
Twelve individuals of varying sizes ranging from 1.4 m to 4.1 m, were collected from three locations and
various tissue samples were analysed for metal content. Tissue from muscle, liver, kidney and fat were
analysed for Al, Cu, Cr, Fe, Mn, Ni, Pb, Section ranger and Zn. As this was the first data of its kind to be
collected, no meaningful conclusions could be reached, except to offer the data as base line data and for
future comparisons. There was however a correlation between Fe concentration in muscle tissue and
body size, total length (TL). An increase in TL resulted in an increase in Fe concentration. The opposite
were found with Fe in fat tissue. Smaller crocodiles (TL) had higher concentrations of Fe in their fat
tissues.
Besides the large amount of base line data that resulted from this study, it also highlighted the shortage of knowledge on this species, particularly in Kruger, to enable us to manage and protect them successfully
Incidence of retinopathy of prematurity in very-low-birth-weight infants born at Kalafong hospital, Pretoria
Introduction. Retinopathy of prematurity (ROP) is a complication of prematurity, is diagnosed by ophthalmological screening of infants at risk (birth weight
_ 1 500 g), and may lead to blindness. The incidence of ROP is under-reported in developing countries, including South Africa. Published data from the USA (CRYO-ROP) show that black infants have a lower incidence of threshold ROP than their white counterparts (3.2% v. 7.4%). Preliminary results of a screening programme initiated at Kalafong Hospital in 1999 are reported.
Aim. To determine the incidence of ROP in infants with a birth weight of _ 1 500 g born at Kalafong Hospital.
Patients and methods. Consecutive infants were enrolled at birth and screened for ROP 4 - 6 weeks later by indirect ophthalmoscopy. Repeat examinations were performed until vascularisation was complete or until the infant reached a postconceptional age of 40 weeks. Infants with stage 3 ROP who developed threshold disease were treated with cryotherapy or laser therapy.
Results. One hundred and forty-five infants were enrolled over 10 months (15 February 1999 - 25 December 1999); of these 94 were screened. Of the remaining 51 infants, 24 died before screening and 27 were discharged before screening and were lost to follow-up. ROP was diagnosed in 23 of the 94 infants screened (24.5%). Stage 1 and 2 ROP occurred in 17 of the infants screened (18.1%) and stage 3 ROP in 6 (6.4%), of whom 4 (median birth weight 995 g, range
900 - 1 450 g) developed threshold ROP and were treated.
Conclusions. The incidence of ROP in black very-low-birth-weight infants born at Kalafong Hospital is 24.5%. The incidence of threshold ROP is 4.3% (3.2% in infants _ 1 250 g) and correlates with published data from the USA. Infants with a birth weight _ 1 500 g should receive ophthalmological screening to diagnose stage 3 ROP timeously.
(South African Medical Journal: 2002 92(12): 986-989
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