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Open Access
[1,2-Bis(diphenylphosphino)ethane]-diiodidoplatinum(II) dichloromethane disolvate
(2007) Sivaramakrishna, Akella; Su, Hong; Moss, John R
In the title compound, [PtI2(C26H24P2)]·2CH2Cl2, the PtI2(dppe) [dppe = 1,2-bis(diphenylphosphino)ethane] molecules possess twofold rotation symmetry. The Pt coordination displays a square-planar arrangement, with the sum of the angles around the Pt atom being 360.01 (2)°. The Pt-I distance is 2.6484 (5) Å. In the crystal structure, intermolecular C-H...I contacts link the PtI2(dppe) molecules into rows along the c axis, with a C...I distance of 3.873 (5) Å.
Open Access
1,7-Dimethylpentacyclo[5.4.0.02,6.-03,10.05,9]undecane-8,11-dione
(International Union of Crystallography, 2010) Chakka, Sai Kumar; Onajole, Oluseye K; Govender, Thavendran; Maguire, Glenn E M; Su, Hong; Kruger, Hendrik G
The structure of the title compound, C13H14O2, a pentacycloundecane cage derivative, exhibits unusual Csp3 —Csp3 singlebond lengths ranging from 1.505 (3) to 1.607 (2) A˚ and strained bond angles as small as 88.7 (1) and as large as 121.0 (2). In this meso compound, an internal non-crystallographic mirror plane exists, bisecting the molecule. In the crystal, weak C—HO hydrogen bonds link the molecules into an infinite spiral about a twofold screw axis along the [100] direction.
Open Access
100 years old and still making history: The centenary of the Department of Historical Studies at the University of Cape Town
(2004) Phillips, Howard
Observing institutional birthdays is not something academic historians readily undertake nowadays – their training makes them habitually wary of the constructed nature of such events and of the self-preening which usually accompanies them. All too often such occasions become part of a celebration of an invented tradition of origins, in which founders’ days are ‘seized on with alacrity for displays of pageantry, where, with high-ranking officials ever present, the narrative inevitably extol[s] … supposed progress and virtues’.1 However, commemorating a centenary is perhaps in a different category, for doing so has long roots in Western culture, dating back to the Biblical Jubilee, the Roman Catholic Church’s first Holy Year in 1300 and the veneration of the decimal system by the European Enlightenment. This makes marking a centenary seem quite natural, so easing the discomfort of historians with such an occasion. Moreover, when, as in the case of the centenary of the foundation of the University of Cape Town’s (UCT) chair of history in 2003, the original event also signalled the inception of history as a university discipline in its own right in subSaharan Africa, the inducement to commemorate this step is difficult to resist. Added to this, 100 years is a meaningful timespan for reflecting on an institution, being long enough for a degree of historical perspective but short enough to permit the voices of some of the actors to be clearly heard too, perhaps once and – thanks to the tape recorder and video camera – forever. In a centenary year, therefore, both a microscope and telescope can be employed to good effect. It was with such ideas in mind that in 2002 UCT’s Department of Historical Studies contemplated its coming centenary and decided not to let it pass unnoticed.
Open Access
A 1000-year carbon isotope rainfall proxy record from South African baobab trees (Adansonia digitata L.)
(Public Library of Science, 2015) Woodborne, Stephan; Hall, Grant; Robertson, Iain; Patrut, Adrian; Rouault, Mathieu; Loader, Neil J; Hofmeyr, Michele
A proxy rainfall record for northeastern South Africa based on carbon isotope analysis of four baobab ( Adansonia digitata L.) trees shows centennial and decadal scale variability over the last 1,000 years. The record is in good agreement with a 200-year tree ring record from Zimbabwe, and it indicates the existence of a rainfall dipole between the summer and winter rainfall areas of South Africa. The wettest period was c. AD 1075 in the Medieval Warm Period, and the driest periods were c. AD 1635, c. AD 1695 and c. AD1805 during the Little Ice Age. Decadal-scale variability suggests that the rainfall forcing mechanisms are a complex interaction between proximal and distal factors. Periods of higher rainfall are significantly associated with lower sea-surface temperatures in the Agulhas Current core region and a negative Dipole Moment Index in the Indian Ocean. The correlation between rainfall and the El Niño/Southern Oscillation Index is non-static. Wetter conditions are associated with predominantly El Niño conditions over most of the record, but since about AD 1970 this relationship inverted and wet conditions are currently associated with la Nina conditions. The effect of both proximal and distal oceanic influences are insufficient to explain the rainfall regime shift between the Medieval Warm Period and the Little Ice Age, and the evidence suggests that this was the result of a northward shift of the subtropical westerlies rather than a southward shift of the Intertropical Convergence Zone.
Open Access
The 2004 re-assessment of the South African sardine and anchovy populations to take account of revisions to earlier data and recent record abundances
(National Inquiry Services Centre (NISC), 2009) de Moor, Carryn L; Butterworth, Doug S
Hydroacoustic surveys off the coast of South Africa over the early years of the 21st century indicated that both the sardine Sardinops sagax and anchovy Engraulis encrasicolus populations had simultaneously reached record abundances. The South African pelagic fishery is regulated using an Operational Management Procedure (OMP). The OMP in use at that time had been developed using data from the two populations prior to this rapid and substantial increase in abundances. This paper documents the revised assessments that were urgently required to provide a basis to update the OMP. These assessments resulted in a changed perception of the status and productivity of these populations. In particular, estimates of the stock-recruitment relationships and the extent of variation about them, which play a key role in evaluating risk when developing OMPs, altered substantially from estimates derived from earlier assessments.
Open Access
2MASS J0516288+260738: Discovery of the first eclipsing late K + Brown dwarf binary system?
(2003) Schuh, S L; Handler, G; Drechsel, H; Hauschildt, P; Dreizler, S; Medupe, R; Karl, C; Napiwotzki, R; Kim, S-L; Park, B-G; Wood, M A; Paparó, M; Szeidl, B; Virághalmy, G; Zsuffa, D; Hashimoto, O; Kinugasa, K; Taguchi, H; Kambe, E; Leibowitz, E; Ibbetson, P; Lipkin, Y; Nagel, T; Göhler, E; Pretorius, M L
We report the discovery of a new eclipsing system less than one arcminute south of the pulsating DB white dwarf
Open Access
30 Days in the life: daily nutrient balancing in a wild chacma baboon
(Public Library of Science, 2013) Johnson, Caley A; Raubenheimer, David; Rothman, Jessica M; Clarke, David; Swedell, Larissa
For most animals, the ability to regulate intake of specific nutrients is vital to fitness. Recent studies have demonstrated nutrient regulation in nonhuman primates over periods of one observation day, though studies of humans indicate that such regulation extends to longer time frames. Little is known about longer-term regulation in nonhuman primates, however, due to the challenges of multiple-day focal follows. Here we present the first detailed study of nutrient intake across multiple days in a wild nonhuman primate. We conducted 30 consecutive all day follows on one female chacma baboon ( Papio hamadryas ursinus ) in the Cape Peninsula of South Africa. We documented dietary composition, compared the nutritional contribution of natural and human-derived foods to the diet, and quantified nutrient intake using the geometric framework of nutrition. Our focus on a single subject over consecutive days allowed us to examine daily dietary regulation within an individual over time. While the amounts varied daily, our subject maintained a strikingly consistent balance of protein to non-protein (fat and carbohydrate) energy across the month. Human-derived foods, while contributing a minority of the diet, were higher in fat and lower in fiber than naturally-derived foods. Our results demonstrate nutrient regulation on a daily basis in our subject, and demonstrate that she was able to maintain a diet with a constant proportional protein content despite wide variation in the composition of component foods. From a methodological perspective, the results of this study suggest that nutrient intake is best estimated over at least an entire day, with longer-term regulatory patterns (e.g., during development and reproduction) possibly requiring even longer sampling. From a management and conservation perspective, it is notable that nearly half the subject's daily energy intake derived from exotic foods, including those currently being eradicated from the study area for replacement by indigenous vegetation.
Open Access
The 341C/T polymorphism in the GSTP1 gene is associated with increased risk of oesophageal cancer
(BioMed Central Ltd, 2010) Li, Dongping; Dandara, Collet; Parker, M Iqbal
BACKGROUND: The Glutathione S-transferases (GSTs) comprise a group of enzymes that are critical in the detoxification of carcinogens. In this study the effects of polymorphisms in these genes on the risk of developing oesophageal squamous cell carcinoma (OSCC) were evaluated in a hospital-based case-control study in two South African population groups. Genetic polymorphisms in GSTs were investigated in 245 patients and 288 controls samples by PCR-RFLP analysis. RESULTS: The GSTP1 341T variant was associated with significantly increased risk of developing OSCC as observed from the odds ratios for the GSTP1 341C/T and GSTP1 341T/T genotypes (OR = 4.98; 95%CI 3.05-8.11 and OR = 10.9; 95%CI 2.43-49.1, respectively) when compared to the homozygous GSTP1 341C/C genotype. The risk for OSCC in the combined GSTP1 341C/T and T/T genotypes was higher in tobacco smokers (OR = 7.51, 95% CI 3.82-14.7), alcohol consumers (OR = 15.3, 95% CI 1.81-12.9) and those using wood or charcoal for cooking and heating (OR = 12.1, 95% CI 3.26-49) when compared to those who did not smoke tobacco, or did not consume alcohol or user other forms of fuel for cooking and heating. Despite the close proximity of the two GSTP1 SNPs (313A>G and 341C>T), they were not in linkage disequilibrium in these two population groups (D':1.0, LOD: 0.52, r2: 0.225). The GSTP1 313A/G polymorphism on the other hand, did not display any association with OSSC. The homozygous GSTT1*0 genotype was associated with increased risk of OSCC (OR = 1.71, 95%CI 1.18-2.46) while the homozygous GSTM1*0 genotype was associated with significantly decreased risk of OSCC in the Mixed Ancestry subjects (OR= 0.39, 95%CI 0.25-0.62). CONCLUSIONS: This study shows that the risk of developing OSCC in the South African population can be partly explained by genetic polymorphisms in GST coding genes and their interaction with environmental factors such as tobacco smoke and alcohol consumption.
Open Access
365 days of openness: The emergence of OER at the University of Cape Town
(Athabasca University Press, 2013) Hodgkinson-Williams, Cheryl; Paskevicius, Michael; Cox, Glenda; Shaikh, Shihaam; Czerniewicz, Laura; Lee-Pan, Samantha; McGreal, R; Kinuthia, W; Marshall, S; McNamara, T
Historically, resources such as books, journals, newspapers, audio and video recordings have been fairly well curated in university libraries. However, the same cannot be said for teaching and learning materials, unless they have been included in a textbook or study guide. With the growth in digital media, libraries have been extending their curation of scholarly resources to include electronic journals, digital books and reference guides, broadening access to these beyond the physical walls of the library. While the growth in digital technology has prompted academics to create their own customised and contextually specific digital media for use in their teaching in the form of PowerPoint presentations, manuals, handbooks, guides, media resources and websites, these resources are most often stored on personal hard drives, on departmental servers or within password-protected institutional learning management systems. Access to these digital materials is usually limited to registered students undertaking specific courses within specific institutions and usually only disseminated by individual academics or departments.
Open Access
5-Iodo-1-Arylpyrazoles as Potential Benchmarks for Investigating the Tuning of the Halogen Bonding
(2020-12-17) Dumitrescu, Denisa; Shova, Sergiu; Man, Isabela C; Caira, Mino R; Popa, Marcel Mirel; Dumitrascu, Florea
5-Iodo-1-arylpyrazoles are interesting templates for investigating the halogen bond propensity in small molecules other than the already well-known halogenated molecules such as tetrafluorodiiodobenzene. Herein, we present six compounds with different substitution on the aryl ring attached at position 1 of the pyrazoles and investigate them in the solid state in order to elucidate the halogen bonding significance to the crystallographic landscape of such molecules. The substituents on the aryl ring are generally combinations of halogen atoms (Br, Cl) and various alkyl groups. Observed halogen bonding types spanned by these six 5-iodopyrazoles included a wide variety, namely, C–I· · · O, C–I· · · π, C–I· · · Br, C–I· · · N and C–Br· · · O interactions. By single crystal X-ray diffraction analysis combined with the descriptive Hirshfeld analysis, we discuss the role and influence of the halogen bonds among the intermolecular interactions.
Open Access
50 years of Emmonsia disease in humans: the dramatic emergence of a cluster of novel fungal pathogens
(Public Library of Science, 2015) Schwartz, Ilan S; Kenyon, Chris; Feng, Peiying; Govender, Nelesh P; Dukik, Karolina; Sigler, Lynne; Jiang, Yanping; Stielow, J Benjamin; Muñoz, José F; Cuomo, Christina A; Botha, Alfred; Stchigel, Alberto M; De Hoog, G Sybren
New species of Emmonsia-like fungi, with phylogenetic and clinical similarities to Blastomyces and Histoplasma, have emerged as causes of systemic human mycoses worldwide. They differ from classical Emmonsia species by producing a thermally-dependent, yeast-like phase rather than adiaspores, and by causing disseminated infections, predominantly in immunocompromised patients and often with high case-fatality rates. Such differences will be important for clinicians to consider in diagnosis and patient management, and for microbiologists who may encounter these fungi with increasing frequency.
Open Access
9β Polymorphism of the Glucocorticoid Receptor Gene Appears to Have Limited Impact in Patients with Addison’s Disease
(Public Library of Science, 2014) Ross, Ian Louis; Dandara, Collet; Swart, Marelize; Lacerda, Miguel; Schatz, Desmond; Blom, Dirk Jacobus
BACKGROUND: Addison’s disease (AD) has been associated with an increased risk of cardiovascular disease. Glucocorticoid receptor polymorphisms that alter glucocorticoid sensitivity may influence metabolic and cardiovascular risk factors in patients with AD. The 9β polymorphism of the glucocorticoid receptor gene is associated with relative glucocorticoid resistance and has been reported to increase the risk of myocardial infarction in the elderly. We explored the impact of this polymorphism in patients with AD. Materials and METHODS: 147 patients with AD and 147 age, gender and ethnicity matched healthy controls were recruited. Blood was taken in a non-fasted state for plasma lipid determination, measurement of cardiovascular risk factors and DNA extraction. RESULTS: Genotype data for the 9β polymorphism was available for 139 patients and 146 controls. AD patients had a more atherogenic lipid profile characterized by an increase in the prevalence of small dense LDL (p = 0.003), increased triglycerides (p = 0.002), reduced HDLC (p<0.001) an elevated highly sensitive C-reactive protein (p = 0.01), compared with controls. The 9β polymorphism (at least one G allele) was found in 28% of patients and controls respectively. After adjusting for age, gender, ethnicity, BMI and hydrocortisone dose per metre square of body surface area in patients, there were no significant metabolic associations with this polymorphism and hydrocortisone doses were not higher in patients with the polymorphism. CONCLUSIONS: This study did not identify any associations between the 9β polymorphism and cardiovascular risk factors or hydrocortisone dose and determination of this polymorphism is therefore unlikely to be of clinical benefit in the management of patients with AD.
Open Access
A (giant) void is not mandatory to explain away dark energy with a Lemaître-Tolman model
(2010) Célérier, M-N; Bolejko, K; Krasiński, A
Context. Lemaître-Tolman (L-T) toy models with a central observer have been used to study the effect of large scale inhomogeneities on the SN Ia dimming. Claims that a giant void is mandatory to explain away dark energy in this framework are currently dominating.
Open Access
A 40-50kDa Glycoprotein Associated with Mucus is Identified as α-1-Acid Glycoprotein in Carcinoma of the Stomach
(2012) Chirwa, Nthato; Govender, Dhirendra; Ndimba, Bongani; Lotz, Zoe; Tyler, Marilyn; Panieri, Eugenio; KAHN, DELAWIR; Mall, Anwar S
Background and Aim: Secreted gastric mucins are large O-glycosylated proteins of crude mucus gels which are aberrantly expressed in malignancy. An albumin associated 55-65kDa glycoprotein was previously shown in mucus gels in gastric cancer. The aim of this study was to investigate its expression and identification in human gastric tissue. Methods: Mucins were purified from crude mucus scrapings of 16 partial and 11 total resections and a rabbit polyclonal antibody was raised to the 55-65kDa glycoprotein. The location and expression of the glycoprotein was examined in normal gastric mucosa (n=20), intestinal metaplasia (n=18) and gastric cancer (n=27) tissue by immunohistochemistry. Mucins were analyzed by isoelectric focusing (IEF) on 2-D polyacrylamide gels. Identification of the 40-50kDa glycoprotein was by MALDI-TOF MS technique. Plasma levels were examined by Western blotting. Results: Extensive SDS-PAGE analysis gave a PAS positive glycoprotein in the 40-50kDa range, in patients with gastric cancer but not normals. It was expressed in parietal and columnar cells of normal gastric tissue and intestinal metaplasia respectively, and in 22 of 27 gastric cancer specimens. In 2-D PAGE stained with Coomassie Blue there were 3 spots positively identified as alpha-1-acid glycoprotein (AGP) by MALDI-TOF MS technique. PAS staining revealed a single bright spot in the same position but could not be identified. Preliminary measurements showed slightly higher levels of AGP in plasma of patients with gastric carcinoma. Conclusion: AGP levels are increased in gastric tissue and in the plasma of those with carcinoma of the stomach.
Open Access
A 52-Week Placebo-Controlled Trial of Evolocumab in Hyperlipidemia
(2014) Blom, Dirk J; Hala, Tomas; Bolognese, Michael; Lillestol, Michael J; Toth, Phillip D; Burgess, Lesley; Ceska, Richard; Roth, Eli; Koren, Michael J; Ballantyne, Christie M; Monsalvo, Maria Laura; Tsirtsonis, Kate; Kim, Jae B; Scott, Rob; Wasserman, Scott M; Stein, Evan A
BACKGROUND Evolocumab, a monoclonal antibody that inhibits proprotein convertase subtilisin/ kexin type 9 (PCSK9), significantly reduced low-density lipoprotein (LDL) cholesterol levels in phase 2 studies. We conducted a phase 3 trial to evaluate the safety and efficacy of 52 weeks of treatment with evolocumab. METHODS We stratified patients with hyperlipidemia according to the risk categories outlined by the Adult Treatment Panel III of the National Cholesterol Education Program. On the basis of this classification, patients were started on background lipid-lowering therapy with diet alone or diet plus atorvastatin at a dose of 10 mg daily, atorvastatin at a dose of 80 mg daily, or atorvastatin at a dose of 80 mg daily plus ezetimibe at a dose of 10 mg daily, for a run-in period of 4 to 12 weeks. Patients with an LDL cholesterol level of 75 mg per deciliter (1.9 mmol per liter) or higher were then randomly assigned in a 2:1 ratio to receive either evolocumab (420 mg) or placebo every 4 weeks. The primary end point was the percent change from baseline in LDL cholesterol, as measured by means of ultracentrifugation, at week 52. RESULTS Among the 901 patients included in the primary analysis, the overall least-squares mean (±SE) reduction in LDL cholesterol from baseline in the evolocumab group, taking into account the change in the placebo group, was 57.0±2.1% (P<0.001). The mean reduction was 55.7±4.2% among patients who underwent background therapy with diet alone, 61.6±2.6% among those who received 10 mg of atorvastatin, 56.8±5.3% among those who received 80 mg of atorvastatin, and 48.5±5.2% among those who received a combination of 80 mg of atorvastatin and 10 mg of ezetimibe (P<0.001 for all comparisons). Evolocumab treatment also significantly reduced levels of apolipoprotein B, non-high-density lipoprotein cholesterol, lipoprotein(a), and triglycerides. The most common adverse events were nasopharyngitis, upper respiratory tract infection, influenza, and back pain. CONCLUSIONS At 52 weeks, evolocumab added to diet alone, to low-dose atorvastatin, or to high-dose atorvastatin with or without ezetimibe significantly reduced LDL cholesterol levels in patients with a range of cardiovascular risks.
Open Access
A Balanced Approach to IT Project Management
(2007) Smith, Derek; Brock, Susan; Hendricks, Danyal; Linnell, Stephen
The primary objectives of this study were to identify how IT projects can be managed using the Balanced Scorecard approach. Although the research is positioned to have potential application within international project management discipline, the analysis is limited to a South African project management perspective and only internal aspects of managing projects are considered.
Open Access
A biregional survey and review of first-line treatment failure and second-line paediatric antiretroviral access and use in Asia and southern Africa
(2011)
BackgroundTo better understand the need for paediatric second-line antiretroviral therapy (ART), an ART management survey and a cross-sectional analysis of second-line ART use were conducted in the TREAT Asia Paediatric HIV Observational Database and the IeDEA Southern Africa (International Epidemiologic Databases to Evaluate AIDS) regional cohorts.MethodsSurveys were conducted in April 2009. Analysis data from the Asia cohort were collected in March 2009 from 12 centres in Cambodia, India, Indonesia, Malaysia, and Thailand. Data from the IeDEA Southern Africa cohort were finalized in February 2008 from 10 centres in Malawi, Mozambique, South Africa and Zimbabwe.ResultsSurvey responses reflected inter-regional variations in drug access and national guidelines. A total of 1301 children in the TREAT Asia and 4561 children in the IeDEA Southern Africa cohorts met inclusion criteria for the cross-sectional analysis.Ten percent of Asian and 3.3% of African children were on second-line ART at the time of data transfer. Median age (interquartile range) in months at second-line initiation was 120 (78-145) months in the Asian cohort and 66 (29-112) months in the southern African cohort. Regimens varied, and the then current World Health Organization-recommended nucleoside reverse transcriptase combination of abacavir and didanosine was used in less than 5% of children in each region.ConclusionsIn order to provide life-long ART for children, better use of current first-line regimens and broader access to heat-stable, paediatric second-line and salvage formulations are needed. There will be limited benefit to earlier diagnosis of treatment failure unless providers and patients have access to appropriate drugs for children to switch to.
Restricted
A brief history of marine bio-invasions in South Africa
(2009) Griffiths, C L; Mead, A; Robinson, T B
Marine species have been introduced continuously into South Africa for more than 400 years, since the arrival of the first European explorers. Various waves of introduction can be identified over this period, each associated with a different mix of vectors. Early wooden vessels carried specialized wood-boring species, a rich external fouling community, plus semi-terrestrial species associated with dry ballast. Modern steel vessels continue to import fouling species, despite the use of anti-fouling paints, and may ply new routes, bringing additional introductions from novel locations. More modern waves of introduction are associated with use of ballast water and with marine aquaculture. Research on marine bio-invasions in South Africa has a short history, marked by a rapid rate of discovery of introductions. Some 86 marine species are currently regarded as introduced to the region, with a further 39 considered cryptogenic, but this number is increasing rapidly. Moreover, many taxa and regions still remain inadequately explored, indicating that the current list remains far from complete. The reasons for under-reporting of introduced populations are discussed and include lack of sample coverage, misidentification of aliens as native species and erroneous redescriptions of aliens as new, indigenous species. However, the lack of taxonomic expertise across large sections of the biota remains the greatest impediment to progress.
Open Access
A Caledonian college in Cape Town and beyond: An investigation into the foundation(s) of the South African university system
(Stellenbosch University, 2003) Phillips, Howard
Adopting a historical approach, this article traces the origins of key features of the South African university system, namely the general nature of its undergraduate degrees, its heavy reliance on lectures to convey information and its extensive use of examinations to assess levels of student achievement. This historical investigation finds the roots of these features in the unreformed Scottish university system which was enthusiastically embraced by South Africa's first two teaching universities, the University of Cape Town (UCT) and Stellenbosch, in 1918, and which then was adopted by those universities which were set up in their image during the next 70 years. The article suggests that any attempt to reform the country's university system today must take account of the historical circumstances which produced it originally.
Open Access
A case for integrating human rights in public health policy
(2006) London, Leslie
In a global environment where human rights and well-being are coming under increasing threat, both from the spectre of terrorism and from the counter-reaction to it,1 and where international governance systems continue to pay lip service to poverty reduction while encouraging unbridled private accumulation of wealth resulting in huge inequalities between and within countries,2,3 the need to make human rights considerations an integral part of how public health policies are formulated cannot be overemphasised. Contestation over entitlements to socio-economic rights has troubled health care systems worldwide, from resource-poor settings in Africa, where questions have been raised as to whether human rights approaches are best suited to addressing the problem of AIDS in Africa,4,5 through to the over-consumptive USA where universal access to health care remains a policy objective doomed to unfulfilment under market-fixated economic systems.6,7