Screening for retinopathy of prematurity in a provincial hospital in Port Elizabeth, South Africa

Background. Retinopathy of prematurity (ROP) is an emerging public health problem in many middle-income countries where improved neonatal survival rates coupled with inadequate health resources have created a new epidemic. There are limited available data on the magnitude of the problem, and screening in South African (SA) hospitals has not been uniformly practised.Objective. To describe the results of various interventions implemented over a 6-year period while developing a new ROP screening service in a provincial hospital in Port Elizabeth, SA.Method. A retrospective case folder review of ROP screening at Dora Nginza Hospital, Port Elizabeth, SA, over the 6-year period 2009 - 2014 was conducted.Results. A total of 919 new cases were seen. Fifteen patients received treatment for type 1 ROP (T1ROP), 223 had type 2 (T2) or earlier ROP, 1 had stage 4 ROP and 6 had stage 5 ROP. The combination of healthcare worker education, improved equipment and human resources and the introduction of dual responsibility for case referrals resulted in an increase in the number of new infants screened from 33 in year 1 to 292 in year 6. The number of infants who were screened late decreased from 33/33 (100%) in year 1, prior to the interventions, to 23/292 in the final year (7.9%). Improved oxygen delivery and adequate oxygen saturation monitoring contributed to a decrease in the incidence of T1ROP from 1.5% to 1% over 1 year and in the incidence of T2 or earlier ROP from 30.3% to 24%.Conclusions. Better management of ROP can be achieved through adequate provision of healthcare professionals and material resources coupled with education and a well-supported referral system. A close working relationship between paediatricians and ophthalmologists results in a more efficient screening programme

Real time imaging of two-dimensional iron oxide spherulite nanostructure formation

The formation of complex hierarchical nanostructures has attracted a lot of attention from both the fundamental science and potential applications point of view. Spherulite structures with radial fibrillar branches have been found in various solids; however, their growth mechanisms remain poorly understood. Here, we report real time imaging of the formation of two-dimensional (2D) iron oxide spherulite nanostructures in a liquid cell using transmission electron microscopy (TEM). By tracking the growth trajectories, we show the characteristics of the reaction front and growth kinetics. Our observations reveal that the tip of a growing branch splits as the width exceeds certain sizes (5.5–8.5 nm). The radius of a spherulite nanostructure increases linearly with time at the early stage, transitioning to nonlinear growth at the later stage. Furthermore, a thin layer of solid is accumulated at the tip and nanoparticles from secondary nucleation also appear at the growing front which later develop into fibrillar branches. The spherulite nanostructure is polycrystalline with the co-existence of ferrihydrite and Fe3O4 through-out the growth. A growth model is further established, which provides rational explanations on the linear growth at the early stage and the nonlinearity at the later stage of growth. [Figure not available: see fulltext.]

Precedence-constrained scheduling problems parameterized by partial order width

Negatively answering a question posed by Mnich and Wiese (Math. Program. 154(1-2):533-562), we show that P2|prec,$p_j{\in}\{1,2\}$|$C_{\max}$, the problem of finding a non-preemptive minimum-makespan schedule for precedence-constrained jobs of lengths 1 and 2 on two parallel identical machines, is W[2]-hard parameterized by the width of the partial order giving the precedence constraints. To this end, we show that Shuffle Product, the problem of deciding whether a given word can be obtained by interleaving the letters of $k$ other given words, is W[2]-hard parameterized by $k$, thus additionally answering a question posed by Rizzi and Vialette (CSR 2013). Finally, refining a geometric algorithm due to Servakh (Diskretn. Anal. Issled. Oper. 7(1):75-82), we show that the more general Resource-Constrained Project Scheduling problem is fixed-parameter tractable parameterized by the partial order width combined with the maximum allowed difference between the earliest possible and factual starting time of a job.Comment: 14 pages plus appendi

Is temperament a key to the success of teaching innovation?

Introduction. A section of the undergraduate curriculum was revised due to consistently poor student evaluation. The chosen didactic method for achieving this change was reciprocal peer teaching. This innovation may have required academic members of staff to adapt to a new teaching style. Method. Staff members determined their Keirsey temperament and were given a report on its interpretation. They participated in training on student-focused teaching techniques and completed the Approaches to Teaching Inventory (ATI) of their preferred approach to teaching. Their subsequent sessions with students were videotaped and analysed for features of student-focused, as opposed to teacher-focused, teaching. Results. There was a link between temperament type and apparent delivery of student-focused teaching. Staff members’ perceptions of their approach to teaching did not correspond to their actual teaching behaviour. Discussion. Staff development strategies could take into account individual temperaments in order to direct their professional development for the full spectrum of flexible teaching skills. Alternatively, teaching teams should be created in a way that takes account of different temperament types. Conclusion. Temperament does play a key role in adaptation to innovation

Web Drugs: Anaesthetics Automated Scheduling System

Web Drugs is an automated anaesthesia roster scheduling system, designed for the UCT Anaesthesia Department at Groote Schuur Hospital. The system consists of three parts, each which make up a part of the Web Drugs system. The system follows a strict set of Rational Unified Process software engineering methodology

Complexity and Inapproximability Results for Parallel Task Scheduling and Strip Packing

We study the Parallel Task Scheduling problem $Pm|size_j|C_{\max}$ with a constant number of machines. This problem is known to be strongly NP-complete for each $m \geq 5$, while it is solvable in pseudo-polynomial time for each $m \leq 3$. We give a positive answer to the long-standing open question whether this problem is strongly $NP$-complete for $m=4$. As a second result, we improve the lower bound of $\frac{12}{11}$ for approximating pseudo-polynomial Strip Packing to $\frac{5}{4}$. Since the best known approximation algorithm for this problem has a ratio of $\frac{4}{3} + \varepsilon$, this result narrows the gap between approximation ratio and inapproximability result by a significant step. Both results are proven by a reduction from the strongly $NP$-complete problem 3-Partition

Solar wind speed theory and the nonextensivity of solar corona

The solar corona is a complex system, with nonisothermal plasma and being in the self-gravitating field of the Sun. So the corona plasma is not only a nonequilibrium system but also a nonextensive one. We estimate the parameter of describing the degree of nonextensivity of the corona plasma and study the generalization of the solar wind speed theory in the framework of nonextensive statistical mechanics. It is found that, when use Chapman's corona model (1957) as the radial distribution of the temperature in the corona, the nonextensivity reduces the gas pressure outward and thus leads a significant deceleration effect on the radial speed of the solar wind.Comment: 12 pages,1 figure, 1 table, 21 references; UN/ESA/NASA Workshop on Basic Space Science and the International Heliophysical Year 2007, National Astronomical Observatory of Japan, 18-22 June, 2007, Tokyo, Japa

Nutritional status of renal transplant patients

Objective. To assess the effect of renal transplantation on the nutritional status of patients.Design. Prospective descriptive study.Setting. Renal Transplant Clinic at Tygerberg Hospital, Western Cape.Subjects. Fifty-eight renal transplant patients from Tygerberg Hospital were enrolled in the study. The sample was divided into two groups of 29 patients each: group 1, less than 28 months post-transplant; and group 2, more than 28 months post-transplant.Outcome measures. Nutritional status assessment comprised biochemical evaluation, a dietary history, anthropometric measurements and a clinical examination.Results. Serum vitamin B6 levels were below normal in 56% of patients from group 1 and 59% from group 2. Vitamin B6 intake, however, was insufficient in only 14% of patients from group 1and10% from group 2. Serum vitamin C levels were below normal in 7% of patients from group 1 and 24% from group 2, while vitamin C intake was insufficient in 21%and14% of patients from groups 1 and 2 respectively. Serum magnesium levels were below normal in 55% of patients from group 1, and in 28% from group 2. Serum albumin and cholesterol levels increased significantly during the post-transplant period in the total sample (P = 0.0001). There was also a significant increase in body mass index (P = 0.0001) during the post-transplant period.Conclusions. Several nutritional abnormalities were observed, which primarily reflect the side-effects of immunosuppressive therapy. The causes, consequences and treatment of the vitamin B6 and vitamin C deficiencies in renal transplant recipients need further investigation

Financial Accounting 3B

Exam paper for second semester: Financial Accounting 3

Test of a Novel Streptococcus pneumoniae Serotype 6C Type Specific Polyclonal Antiserum (Factor Antiserum 6d) and Characterisation of Serotype 6C Isolates in Denmark

<p>Abstract</p> <p>Background</p> <p>In 2007, Park <it>et al. </it>identified a novel serotype among <it>Streptococcus pneumoniae </it>serogroup 6 which they named serotype 6C. The aim of this study was to evaluate with the Neufeld test a novel <it>S. pneumoniae </it>serotype 6C type specific polyclonal antiserum. In addition, serotype 6C isolates found in Denmark in 2007 and 2008 as well as eight old original serotype 6A isolates were characterised.</p> <p>Methods</p> <p>In this study, 181 clinical <it>Streptococcus pneumoniae </it>isolates from Denmark 2007 and 2008 were examined; 96 isolates had previously been typed as serotype 6A and 85 as serotype 6B. In addition, eight older isolates from 1952 to 1987, earlier serotyped as 6A, were examined. Serotype 6C isolates were identified by PCR and serotyping with the Neufeld test using the novel type specific polyclonal antiserum, factor antiserum 6 d, in addition to factor antisera 6b, 6b* (absorbed free for cross-reactions to serotype 6C) and 6c. All antisera are commercially available and antiserum 6b obtained from the supplier after 1 January 2009 is antiserum 6b*. All serotype 6C isolates were further characterised using multi-locus sequence typing.</p> <p>Results</p> <p>When retesting all 96 original serotype 6A isolates by PCR and the Neufeld test, 29.6% (24 of 81) of the invasive isolates in Denmark from 2007 and 2008 were recognised as serotype 6C. In addition, three of eight old isolates originally serotyped as 6A were identified to be serotype 6C. The oldest serotype 6C isolate was from 1962. The serotype 6C isolates belonged to eleven different sequence types (ST) and nine clonal complexes (CC), ST1692 (CC395), ST386 (CC386) and ST481 (CC460) were the predominant types.</p> <p>Conclusions</p> <p>We tested a novel polyclonal antiserum 6 d, as well as modified antiserum 6b*, provided a scheme for the serotyping of <it>S. pneumoniae </it>serogroup 6 using the Neufeld test and compared the serotyping method with PCR based methods. The two types of methods provided the same results. In future, it will, therefore, be possible to test also serotype 6C in accordance to the standard method for serotyping of <it>S. pneumoniae </it>recommended by WHO.</p> <p>Among all invasive isolates from Denmark 2007 and 2008, serotype 6C constituted 29.6% of the original serotype 6A isolates. The serotype 6C isolates were found to be diverse belonging to a number of different STs and CCs of which most have been observed in other countries previously. Serotype 6C is regarded as an "old" serotype being present among <it>S. pneumoniae </it>isolates in Denmark for at least 48 years. The genetic diversity of serotype 6C isolates and their genetic relationship to other serotypes suggested that serotype 6C strains may have arisen from several different independent recombination events involving different parental strains such as serotypes 6A, 6B, 23F and 4.</p