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Johannesburg, South Africa

The University of the Witwatersrand, Johannesburg, is a multi-campus South African public research university situated in the northern areas of central Johannesburg. It is more commonly known as Wits University. The university has its roots in the mining industry, as do Johannesburg and the Witwatersrand in general. Founded in 1896 as the South African School of Mines in Kimberley, it is the third oldest South African university in continuous operation, after the University of Cape Town , and Stellenbosch University .In 1959, the Extension of University Education Act forced restricted registrations of black students for most of the apartheid era; despite this, several notable black leaders graduated from the university. It became desegregated once again prior to the abolition of apartheid in 1990. Several of apartheid's most provocative critics, of either European or African descent, were one-time students and graduates of the university.The university has an enrolment of 27,934 students as of 2010, of which approximately 4,566 live on campus in the university's 18 residences. As of 2010, 67.7% of the university's total enrolment is for undergraduate study, with the remaining 32.3% being postgraduate. Wikipedia.

Proprotein convertase subtilisin kexin type 9 (PCSK9) is an enzyme that impairs low-density lipoprotein cholesterol (LDL-C) clearance from the plasma by promoting LDL receptor degradation. Patients with familial hypercholesterolemia (FH) have reduced or absent LDL receptors and should therefore have elevated PCSK9 levels. Fasting lipograms and PCSK9 levels were measured 51 homozygous FH (HoFH), 20 heterozygous FH (HeFH), and 20 normocholesterolemic control subjects. Levels were repeated following high-dose statin therapy. LDL-C levels were significantly higher in untreated HoFH (13.4±0.7 mmol/L) and HeFH patients (7.0±0.2 mmol/L) compared with controls (2.6±0.1 mmol/L) (P<0.01). Statin therapy decreased LDL-C levels from 13.4±0.7 to 11.1±0.7 mmol/L in HoFH and from 7.0±0.2 to 3.6±0.2 mmol/L in HeFH patients (P<0.01). PCSK9 levels were higher in untreated HoFH (279±27 ng/mL) and HeFH (202±14 ng/mL) than in controls (132±10 ng/mL) (both P<0.01). High-dose statin therapy increased PCSK9 levels from 279±27 to 338±50 ng/mL in HoFH, and significantly so in the HeFH patients from 202±14 to 278±20 ng/mL (P<0.01). Linear regression analysis showed a correlation between PCSK9 and LDL-C (r=0.6769; P<0.0001); however, this was eliminated following statin therapy (r=0.2972; P=0.0625). PCSK9 levels are elevated in untreated FH patients, particularly in those with HoFH. High-dose statin therapy further increases PCSK9 levels. PCSK9 inhibitors might be a beneficial therapy for FH patients, even in those with HoFH. Source

The concept of remote capture involved in the creation and use of snares and traps is one of several indicators that can be used for the recognition of enhanced working memory and complex cognition. It can be argued that this humble technology is a more reliable indicator of complex cognition than encounter hunting, for example with spears. It is difficult to recognize snares and traps archaeologically because they are generally made from materials that do not preserve well. To infer their presence in the past, it is therefore necessary to rely on circumstantial evidence such as mortality profiles, taxonomic diversity and high frequencies of creatures that are susceptible to capture in snares or traps. Clearly there are some problems with using snares to infer complex cognition because people do not necessarily choose meat-getting strategies with the lowest costs. Although snares make economic sense because they reduce search costs, their use by modern hunters is not associated with the type of status accorded to other means of hunting. Social demands, more than economic or environmental ones, may consequently have determined the amount of snaring and trapping that occurred in the past. Because of social attitudes, an absence of snaring need not mean that people were incapable of using this technique. At Sibudu, a South African Middle Stone Age site, snares or other non-selective capture techniques may have been used during the Howiesons Poort and perhaps also the Still Bay Industry. The circumstantial evidence consists of 1. high frequency representations of animals that prefer forested environments, including the tiny blue duiker (adult and juvenile) and the dangerous bushpig, 2. high frequencies of small mammals, 3. high taxonomic diversity and, 4. the presence of small carnivores. Importantly, the Howiesons Poort faunal assemblage is different from that in more recent Middle Stone Age occupations of the site. © 2009 Elsevier Ltd. All rights reserved. Source

Caputa P.,University of Witwatersrand
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2012

We consider high energy scattering of open superstrings in flat spacetime. It is shown that in this regime amplitudes are dominated by minimal supersurfaces spanned by lightlike supercontours built of the on-shell momenta. We demonstrate how using a generalization of the functional over reparametrizations of the boundary one can extract the area of the minimal supersurfaces directly from the lightlike contour. Exponent of the area correctly reproduces RNS amplitudes. We also comment on possible implementation of the supercontours to Wilson loops/Scattering amplitudes duality. © 2012 Elsevier B.V. Source

Stein E.A.,University of Cincinnati | Raal F.,University of Witwatersrand
Annual Review of Medicine | Year: 2014

Published phase I and II trials with two fully human monoclonal antibodies to PCSK9 have provided comprehensive evidence that inhibiting PCSK9 is a very effective method to reduce low-density lipoprotein cholesterol (LDL-C). In all populations studied so far, whether on statins or LDL-C-reducing diet alone, with or without a genetic defect in the LDL receptor, and in subjects intolerant to statins, the LDL-C reductions have been large and consistent. Even the most efficacious statin, rosuvastatin, at its highest dose has not achieved such reductions. The clinical trials have established that monoclonal antibody therapy targeted to PCSK9 may be administered subcutaneously every two or four weeks. Current data suggest these drugs will provide an effective therapeutic option for LDL-C reduction and that, if proven safe in phase III trials, they will be as important to LDL-C control, and likely to cardiovascular disease risk reduction, as statins have been over the past three decades. © 2014 by Annual Reviews. All rights reserved. Source

Giataganas D.,University of Witwatersrand
Journal of High Energy Physics | Year: 2012

We calculate the static potential, the drag force and the jet quenching parameter in strongly coupled anisotropic N = 4 super Yang-Mills plasma. We find that the jet quenching is in general enhanced in presence of anisotropy compared to the isotropic case and that its value depends strongly on the direction of the moving quark and the direction along which the momentum broadening occurs. The jet quenching is strongly enhanced for a quark moving along the anisotropic direction and momentum broadening happens along the transverse one. The parameter gets lower for a quark moving along the transverse direction and the momentum broadening considered along the anisotropic one. Finally, a weaker enhancement is observed when the quark moves in the transverse plane and the broadening occurs on the same plane. The drag force for quark motion parallel to the anisotropy is always enhanced. For motion in the transverse space the drag force is enhanced compared to the isotropic case only for quarks having velocity above a critical value. Below this critical value the force is decreased. Moreover, the drag force along the anisotropic direction is always stronger than the force in the transverse space. The diffusion time follows exactly the inverse relations of the drag forces. The static potential is decreased and stronger decrease observed for quark-antiquark pair aligned along the anisotropic direction than the transverse one. We finally comment on our results and elaborate on their similarities and differences with the weakly coupled plasmas. © SISSA 2012. Source

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