Lean system implementation strategy and knowledge framework

Current research has exposed the fact that organisations in South Africa grapple with the implementation of lean systems. Lean systems affect the entire organisation and require strategies which link core and supporting processes from end-to-end. In many cases it requires the redesign of the supply chains’ supporting activities or processes that provide added value to the business processes of the organisation. Contemporary research postulates that to be successful, an organisation should have specific objectives when implementing a lean system. The objectives would ensure a smooth, rapid flow of materials and or work through a system. Primarily it compels management to perform a health-check or business capability performance gap analysis before attempting to formulate a lean implementation strategy. The objective of the paper based on topical research, is the development of a health-check. In developing a knowledge framework and measurement model, various tools were used for statistical analysis. The framework would assist organisations in identifying critical success factors during the implementation of lean. It addresses lean implementation strategy confirming the overall business improvement endeavour through value adding activities. An added advantage is that it would assist an organisation in performing a capability performance health-check before embarking on a lean or value adding project

Requirements practitioner behaviour in social context : a survey

The purpose of this research paper is to discover the social behaviour of practitioners that causes the communication breakdowns during the requirements engineering process. Requirements emerge from the social interaction and communication between the requirements practitioner and the various stakeholders. The main problems with the requirements engineering process are communication and coordination breakdowns, as well as the lack of domain knowledge or understanding of the problem. These challenges are all related to the social interaction during the requirements engineering process that impacts the quality of requirements. In practice, requirements are still produced with errors which then lead to unsuccessful solutions to problems. The ultimate goal of any practitioner is delivering a solution fit for purpose first time around. If the social patterns of practitioners that deliver quality requirements are known and compared with those that do not deliver quality requirements, individual performance can be adjusted. The results of this study confirmed that quality of requirements is dependent on the communication established between the requirements practitioner and relevant stakeholders. The communication is enabled through the trust relationships between the parties. A description of how practitioners behave during the requirements process is provided. By discovering these interaction patterns, communication can be improved and made more effective. Additionally, the relationships between the practitioners and their stakeholders are described. These trust patterns provide insight into the levels of collaboration, communication and sharing of knowledge between the practitioners and their stakeholders. By identifying these relationship patterns, the value each party receives from the relationships could increase, and the communication breakdowns could be minimised.http://www.saiee.org.za/displaycustomlink.aspx?name=AfricaResearchJournalam201

A South African perspective of the requirements discipline : an industry review

Please read abstract in article.http://www.saiee.org.za/DirectoryDisplay/DirectoryCMSPages.aspx?name=Publications#id=1588&dirname=ARJ&dirid=337am201

Numerical simulations with a first order BSSN formulation of Einstein's field equations

We present a new fully first order strongly hyperbolic representation of the BSSN formulation of Einstein's equations with optional constraint damping terms. We describe the characteristic fields of the system, discuss its hyperbolicity properties, and present two numerical implementations and simulations: one using finite differences, adaptive mesh refinement and in particular binary black holes, and another one using the discontinuous Galerkin method in spherical symmetry. The results of this paper constitute a first step in an effort to combine the robustness of BSSN evolutions with very high accuracy numerical techniques, such as spectral collocation multi-domain or discontinuous Galerkin methods.Comment: To appear in Physical Review

Guideline: Appropriate use of tigecycline

INTRODUCTION: Tigecycline, the first of a new class of antibiotics, the glycylcyclines, was licensed in South Africa for the parenteral treatment of adult patients with complicated intraabdominal infections (cIAIs) and complicated skin and softtissue infections (cSSTIs). METHODS: A multidisciplinary meeting representative of the Association of Surgeons of South Africa, the Critical Care Society of Southern Africa, the Federation of Infectious Diseases Societies of Southern Africa, the South African Thoracic Society and the Trauma Society of South Africa was held to draw up a national guideline for the appropriate use of tigecycline. Background information reviewed included randomised controlled trials, other relevant publications and local antibiotic susceptibility patterns. The initial document was drafted at the meeting. Subsequent drafts were circulated to members of the working group for modification. OUTPUT: The guideline addresses several important aspects of the new agent, summarising key clinical data and highlighting important considerations with the use of the drug. The recommendations in this guideline are based on currently available scientific evidence together with the consensus opinion of the authors. CONCLUSION: This statement was written out of concern regarding the widespread misuse of antibiotics. Its primary intention is to facilitate heterogeneous use of antibiotics as a component of antibiotic stewardship and to highlight the appropriate use of tigecycline in particular.Sponsored through an unrestricted educational grant from Wyeth

Starch safety in resuscitation

The Western Cape Department of Health (WC DoH) has taken a decision to withdraw all intravenous fluids (IVFs) containing hydroxyethyl starch (HES) from hospitals in the Western Cape, with similar action contemplated in the Free State and Gauteng. This was in response to recommendations from: The European Medicines Agency's Pharmacovigilance Risk Assessment Committee (EMA PRAC) that HES IVFs be withdrawn from clinical use. The United Kingdom Medicines and Healthcare Products Regulatory Agency (MHRA) which has issued a recall of all HES IVFs in the UK. The United States Food and Drug Administration which advises that HES IVFs be used with caution in ICU, cardiac surgery and patients with known kidney disease or coagulopathy. Further advice was that HES should be stopped if coagulopathy or renal dysfunction develops, as well as that renal function should be monitored for 90 days after HES administration.http://www.samj.org.zaam2013ay201

HIV Treatment as Prevention: Systematic Comparison of Mathematical Models of the Potential Impact of Antiretroviral Therapy on HIV Incidence in South Africa

Background: Many mathematical models have investigated the impact of expanding access to antiretroviral therapy (ART) on new HIV infections. Comparing results and conclusions across models is challenging because models have addressed slightly different questions and have reported different outcome metrics. This study compares the predictions of several mathematical models simulating the same ART intervention programmes to determine the extent to which models agree about the epidemiological impact of expanded ART. Methods and Findings: Twelve independent mathematical models evaluated a set of standardised ART intervention scenarios in South Africa and reported a common set of outputs. Intervention scenarios systematically varied the CD4 count threshold for treatment eligibility, access to treatment, and programme retention. For a scenario in which 80% of HIV-infected individuals start treatment on average 1 y after their CD4 count drops below 350 cells/µl and 85% remain on treatment after 3 y, the models projected that HIV incidence would be 35% to 54% lower 8 y after the introduction of ART, compared to a counterfactual scenario in which there is no ART. More variation existed in the estimated long-term (38 y) reductions in incidence. The impact of optimistic interventions including immediate ART initiation varied widely across models, maintaining substantial uncertainty about the theoretical prospect for elimination of HIV from the population using ART alone over the next four decades. The number of person-years of ART per infection averted over 8 y ranged between 5.8 and 18.7. Considering the actual scale-up of ART in South Africa, seven models estimated that current HIV incidence is 17% to 32% lower than it would have been in the absence of ART. Differences between model assumptions about CD4 decline and HIV transmissibility over the course of infection explained only a modest amount of the variation in model results. Conclusions: Mathematical models evaluating the impact of ART vary substantially in structure, complexity, and parameter choices, but all suggest that ART, at high levels of access and with high adherence, has the potential to substantially reduce new HIV infections. There was broad agreement regarding the short-term epidemiologic impact of ambitious treatment scale-up, but more variation in longer term projections and in the efficiency with which treatment can reduce new infections. Differences between model predictions could not be explained by differences in model structure or parameterization that were hypothesized to affect intervention impact

Assessment of epidemic projections using recent HIV survey data in South Africa: a validation analysis of ten mathematical models of HIV epidemiology in the antiretroviral therapy era

Background Mathematical models are widely used to simulate the eff ects of interventions to control HIV and to project future epidemiological trends and resource needs. We aimed to validate past model projections against data from a large household survey done in South Africa in 2012. Methods We compared ten model projections of HIV prevalence, HIV incidence, and antiretroviral therapy (ART) coverage for South Africa with estimates from national household survey data from 2012. Model projections for 2012 were made before the publication of the 2012 household survey. We compared adult (age 15–49 years) HIV prevalence in 2012, the change in prevalence between 2008 and 2012, and prevalence, incidence, and ART coverage by sex and by age groups between model projections and the 2012 household survey. Findings All models projected lower prevalence estimates for 2012 than the survey estimate (18·8%), with eight models’ central projections being below the survey 95% CI (17·5–20·3). Eight models projected that HIV prevalence would remain unchanged (n=5) or decline (n=3) between 2008 and 2012, whereas prevalence estimates from the household surveys increased from 16·9% in 2008 to 18·8% in 2012 (diff erence 1·9, 95% CI –0·1 to 3·9). Model projections accurately predicted the 1·6 percentage point prevalence decline (95% CI –0·3 to 3·5) in young adults aged 15–24 years, and the 2·2 percentage point (0·5 to 3·9) increase in those aged 50 years and older. Models accurately represented the number of adults on ART in 2012; six of ten models were within the survey 95% CI of 1·54–2·12 million. However, the diff erential ART coverage between women and men was not fully captured; all model projections of the sex ratio of women to men on ART were lower than the survey estimate of 2·22 (95% CI 1·73–2·71). Interpretation Projections for overall declines in HIV epidemics during the ART era might have been optimistic. Future treatment and HIV prevention needs might be greater than previously forecasted. Additional data about service provision for HIV care could help inform more accurate projections

Antimicrobial susceptibility of gram-negative pathogens isolated from patients with complicated intra-abdominal infections in South African hospitals (SMART Study 2004-2009) : impact of the new carbapenem breakpoints

BACKGROUND: The Study for Monitoring Antimicrobial Resistance Trends (SMART) follows trends in resistance among aerobic and facultative anaerobic gram-negative bacilli (GNB) isolated from complicated intra-abdominal infections (cIAIs) in patients around the world. METHODS: During 2004–2009, three centralized clinical microbiology laboratories serving 59 private hospitals in three large South African cities collected 1,218 GNB from complicated intra-abdominal infections (cIAIs) and tested them for susceptibility to 12 antibiotics according to the 2011 Clinical Laboratory Standards Institute (CLSI) guidelines. RESULTS: Enterobacteriaceae comprised 83.7% of the isolates. Escherichia coli was the species isolated most commonly (46.4%), and 7.6% of these were extended-spectrum b-lactamase (ESBL)-positive. The highest ESBL rate was documented for Klebsiella pneumoniae (41.2%). Overall, ertapenem was the antibiotic most active against susceptible species for which it has breakpoints (94.6%) followed by amikacin (91.9%), piperacillin-tazobactam (89.3%), and imipenem-cilastatin (87.1%), whereas rates of resistance to ceftriaxone, cefotaxime, ciprofloxacin, and levofloxacin were documented to be 29.7%, 28.7%, 22.5%, and 21.1%, respectively. Multi-drug resistance (MDR), defined as resistance to three or more antibiotic classes, was significantly more common in K. pneumoniae (27.9%) than in E. coli (4.9%; p < 0.0001) or Proteus mirabilis (4.1%; p < 0.05). Applying the new CLSI breakpoints for carbapenems, susceptibility to ertapenem was reduced significantly in ESBL-positive E. coli compared with ESBL-negative isolates (91% vs. 98%; p < 0.05), but this did not apply to imipenem-cilastatin (95% vs. 99%; p = 0.0928). A large disparity between imipenem-cilastatin and ertapenem susceptibility in P. mirabilis and Morganella morganii was documented (24% vs. 96% and 15% vs. 92%, respectively), as most isolates of these two species had imipenem-cilastatin minimum inhibitory concentrations in the 2–4 mcg/mL range, which is no longer regarded as susceptible. CONCLUSIONS: This study documented substantial resistance to standard antimicrobial therapy among GNB commonly isolated from cIAIs in South Africa. With the application of the new CLSI carbapenem breakpoints, discrepancies were noted between ertapenem and imipenem-cilastatin with regard to the changes in their individual susceptibilities. Longitudinal surveillance of susceptibility patterns is useful to guide recommendations for empiric antibiotic use in cIAIs.Merck & Co., Inc.http://www.liebertpub.com/overview/surgical-infections/53/am2013ay201

Starch safety in resuscitation

This correspondence is in response to the article: Parrish A, Blockman M, Starch safety in resuscitation − when will we ever learn? S Afr Med J 2013;103(6):365-367. [http://dx.doi.org/10.7196/samj.6969] in three parts:1. Starch safety in resuscitation: Withdrawal of hydroxyethyl starch solutions − a plea for evidence. R E Hodgson, G A Richards, A C Lundgren, M G L Spruyt, J P Pretorius, L R Mathiva, R Dickerson, P D Gopalan 2. Starch safety in resuscitation: Plea for evidence. M F M James, I A Joubert, J L Piercy3. Starch safety in resuscitation: Response from A Parrish and M Blockma