Pretoria, South Africa
Pretoria, South Africa

The University of Pretoria is a multi campus public research university located in Pretoria, the administrative and de facto capital of South Africa. The university was established in 1908 as the Pretoria campus of the Johannesburg based Transvaal University College and is the fourth South African insitution in continuous operation to be awarded university status. Wikipedia.


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News Article | May 3, 2017
Site: www.eurekalert.org

Calls help maintain group cohesion and may provide listeners with cues about the producers Within a group of meerkats, call patterns vary with factors including sex, rank and reproductive season -- but not with stress hormones, according to a study published May 3, 2017 in the open-access journal PLOS ONE by Jelena Mausbach from University of Zurich, Switzerland; Marta Manser from University of Pretoria, South Africa; and colleagues. Meerkats live in family groups with social hierarchies, emitting contact calls that help maintain group cohesion during foraging. These calls are distinctive and have variable rates across individuals, but the influences on this behavior are unknown. To identify factors linked to call patterns, Mausbach, Manser and colleagues analyzed sound recordings and measured fecal stress hormones of 64 meerkats from 9 groups in the wild. The researchers found that call patterns vary with factors such as sex, social status, and reproductive season, suggesting that meerkat calls within a family group provide listeners with cues about the producers. For example, call rates were higher in dominant females and one-year-old males than in other individuals, and were up to five times more frequent during the reproductive season than during the non-reproductive season. However, call patterns were not linked to stress hormones, and the researchers speculate that this may reflect the fact that the calls studied were emitted during the relaxed context of foraging. In your coverage please use this URL to provide access to the freely available article in PLOS ONE: http://journals. Citation: Mausbach J, Braga Goncalves I, Heistermann M, Ganswindt A, Manser MB (2017) Meerkat close calling patterns are linked to sex, social category, season and wind, but not fecal glucocorticoid metabolite concentrations. PLoS ONE 12(5): e0175371. https:/ Funding: This study was funded by the Swiss National Science Foundation(grant no. 31003A_13676 to Marta B. Manser. The long term field site KMP was financed by Cambridge University, Zurich University and Earthwatch. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist.


News Article | April 20, 2017
Site: phys.org

Understanding how the animals do this could lead to treatments for patients suffering crises of oxygen deprivation, as in heart attacks and strokes. "This is just the latest remarkable discovery about the naked mole-rat—a cold-blooded mammal that lives decades longer than other rodents, rarely gets cancer, and doesn't feel many types of pain," says Thomas Park, professor of biological sciences at the University of Illinois at Chicago, who led an international team of researchers from UIC, the Max Delbrück Institute in Berlin and the University of Pretoria in South Africa on the study. In humans, laboratory mice, and all other known mammals, when brain cells are starved of oxygen they run out of energy and begin to die. But naked mole-rats have a backup: their brain cells start burning fructose, which produces energy anaerobically through a metabolic pathway that is only used by plants - or so scientists thought. In the new study, the researchers exposed naked mole-rats to low oxygen conditions in the laboratory and found that they released large amounts of fructose into the bloodstream. The fructose, the scientists found, was transported into brain cells by molecular fructose pumps that in all other mammals are found only on cells of the intestine. "The naked mole-rat has simply rearranged some basic building-blocks of metabolism to make it super-tolerant to low oxygen conditions," said Park, who has studied the strange species for 18 years. At oxygen levels low enough to kill a human within minutes, naked mole-rats can survive for at least five hours, Park said. They go into a state of suspended animation, reducing their movement and dramatically slowing their pulse and breathing rate to conserve energy. And they begin using fructose until oxygen is available again. The naked mole-rat is the only known mammal to use suspended animation to survive oxygen deprivation. The scientists also showed that naked mole-rats are protected from another deadly aspect of low oxygen - a buildup of fluid in the lungs called pulmonary edema that afflicts mountain climbers at high altitude. The scientists think that the naked mole-rats' unusual metabolism is an adaptation for living in their oxygen-poor burrows. Unlike other subterranean mammals, naked mole-rats live in hyper-crowded conditions, packed in with hundreds of colony mates. With so many animals living together in unventilated tunnels, oxygen supplies are quickly depleted. More information: "Fructose-driven glycolysis supports anoxia resistance in the naked mole-rat," Science (2017). science.sciencemag.org/cgi/doi/10.1126/science.aab3896


News Article | April 27, 2017
Site: www.eurekalert.org

IMAGE:  Fukomys livingstoni is by Rebecca Gelertner of Near Bird Studios ( @NearBirdStudios ). view more Two new species of African mole-rat have been discovered by researchers at Queen Mary University of London (QMUL), together with colleagues in Tanzania and at the University of Pretoria. The species, formally described as Fukomys hanangensis and Fukomys livingstoni, were found around Mount Hanang and at Ujiji on the shores of Lake Tanganyika, both in Tanzania. The latter is named after Dr David Livingstone, as Ujiji is the site of the famous meeting in 1871 when Henry Morton Stanley found the explorer, who many thought to be dead, and uttered the famous words "Dr Livingstone, I presume?". The research was published in the journal PeerJ. African mole-rats are subterranean rodents that occur throughout sub-Saharan Africa. They have been widely studied because of the variation in their social and reproductive behaviours. More recently the naked mole-rat (Heterocephalus glaber) has also emerged as a model species for the study of healthy ageing, longevity and cancer resistance. Dr Chris Faulkes, from the School of Biological and Chemical Sciences and lead author of the paper, said: "We would like to find out more about the social behaviour of these new species - our initial studies indicate that they are cooperative breeders like others in their genus." "A clear understanding of African mole-rats' biodiversity and evolutionary relationships has become increasingly important, not least because there are many species in the family, but also because there are a number of genetically unique, distinctive populations that are limited in their distribution - two of which we now formally name and describe fully in our paper." Most of the species in this group of mole-rats (Fukomys) are to the West of the Great African Rift Valley, while these are to the East, out of their normal range. The researchers were therefore keen to characterise these populations and understand how and when they might have got to their current locations, as part of their wider studies on mole-rat biodiversity. The results revealed two distinct evolutionary lineages that constitute previously unnamed species. Detailed genetic analysis suggests that geological and volcanic activity isolated these populations subsequent to their earlier dispersal in to this part of East Africa. The broader scope of the research highlights how genetic data can be used to cross reference the timings of major geological events, and vice versa. Dr Faulkes added: "Our research argues that the biodiversity hotspots in this part of Africa can be understood in terms of landscape evolution in the form of tectonic activity [Rift Valley formation], climatic fluctuations and subsequent expansion and contraction of forest and savannah habitats."


Deprived of oxygen, naked mole-rats can survive by metabolizing fructose just as plants do, researchers report this week in the journal Science. Understanding how the animals do this could lead to treatments for patients suffering crises of oxygen deprivation, as in heart attacks and strokes. "This is just the latest remarkable discovery about the naked mole-rat -- a cold-blooded mammal that lives decades longer than other rodents, rarely gets cancer, and doesn’t feel many types of pain," says Thomas Park, professor of biological sciences at the University of Illinois at Chicago, who led an international team of researchers from UIC, the Max Delbrück Institute in Berlin and the University of Pretoria in South Africa on the study. In humans, laboratory mice, and all other known mammals, when brain cells are starved of oxygen they run out of energy and begin to die. But naked mole-rats have a backup: their brain cells start burning fructose, which produces energy anaerobically through a metabolic pathway that is only used by plants – or so scientists thought. In the new study, the researchers exposed naked mole-rats to low oxygen conditions in the laboratory and found that they released large amounts of fructose into the bloodstream. The fructose, the scientists found, was transported into brain cells by molecular fructose pumps that in all other mammals are found only on cells of the intestine. “The naked mole-rat has simply rearranged some basic building-blocks of metabolism to make it super-tolerant to low oxygen conditions,” said Park, who has studied the strange species for 18 years. At oxygen levels low enough to kill a human within minutes, naked mole-rats can survive for at least five hours, Park said. They go into a state of suspended animation, reducing their movement and dramatically slowing their pulse and breathing rate to conserve energy. And they begin using fructose until oxygen is available again. The naked mole-rat is the only known mammal to use suspended animation to survive oxygen deprivation. The scientists also showed that naked mole-rats are protected from another deadly aspect of low oxygen – a buildup of fluid in the lungs called pulmonary edema that afflicts mountain climbers at high altitude. The scientists think that the naked mole-rats’ unusual metabolism is an adaptation for living in their oxygen-poor burrows. Unlike other subterranean mammals, naked mole-rats live in hyper-crowded conditions, packed in with hundreds of colony mates. With so many animals living together in unventilated tunnels, oxygen supplies are quickly depleted.


News Article | April 21, 2017
Site: www.chromatographytechniques.com

Deprived of oxygen, naked mole-rats can survive by metabolizing fructose just as plants do, researchers report this week in the journal Science. Understanding how the animals do this could lead to treatments for patients suffering crises of oxygen deprivation, as in heart attacks and strokes. “This is just the latest remarkable discovery about the naked mole-rat — a cold-blooded mammal that lives decades longer than other rodents, rarely gets cancer, and doesn’t feel many types of pain,” says Thomas Park, professor of biological sciences at the University of Illinois at Chicago, who led an international team of researchers from UIC, the Max Delbrück Institute in Berlin and the University of Pretoria in South Africa on the study. In humans, laboratory mice, and all other known mammals, when brain cells are starved of oxygen they run out of energy and begin to die. But naked mole-rats have a backup: their brain cells start burning fructose, which produces energy anaerobically through a metabolic pathway that is only used by plants – or so scientists thought. In the new study, the researchers exposed naked mole-rats to low oxygen conditions in the laboratory and found that they released large amounts of fructose into the bloodstream. The fructose, the scientists found, was transported into brain cells by molecular fructose pumps that in all other mammals are found only on cells of the intestine. “The naked mole-rat has simply rearranged some basic building-blocks of metabolism to make it super-tolerant to low oxygen conditions,” said Park, who has studied the strange species for 18 years. At oxygen levels low enough to kill a human within minutes, naked mole-rats can survive for at least five hours, Park said. They go into a state of suspended animation, reducing their movement and dramatically slowing their pulse and breathing rate to conserve energy. And they begin using fructose until oxygen is available again. The naked mole-rat is the only known mammal to use suspended animation to survive oxygen deprivation. The scientists also showed that naked mole-rats are protected from another deadly aspect of low oxygen – a buildup of fluid in the lungs called pulmonary edema that afflicts mountain climbers at high altitude. The scientists think that the naked mole-rats’ unusual metabolism is an adaptation for living in their oxygen-poor burrows. Unlike other subterranean mammals, naked mole-rats live in hyper-crowded conditions, packed in with hundreds of colony mates. With so many animals living together in unventilated tunnels, oxygen supplies are quickly depleted.


News Article | April 21, 2017
Site: www.chromatographytechniques.com

Deprived of oxygen, naked mole-rats can survive by metabolizing fructose just as plants do, researchers report this week in the journal Science. Understanding how the animals do this could lead to treatments for patients suffering crises of oxygen deprivation, as in heart attacks and strokes. “This is just the latest remarkable discovery about the naked mole-rat — a cold-blooded mammal that lives decades longer than other rodents, rarely gets cancer, and doesn’t feel many types of pain,” says Thomas Park, professor of biological sciences at the University of Illinois at Chicago, who led an international team of researchers from UIC, the Max Delbrück Institute in Berlin and the University of Pretoria in South Africa on the study. In humans, laboratory mice, and all other known mammals, when brain cells are starved of oxygen they run out of energy and begin to die. But naked mole-rats have a backup: their brain cells start burning fructose, which produces energy anaerobically through a metabolic pathway that is only used by plants – or so scientists thought. In the new study, the researchers exposed naked mole-rats to low oxygen conditions in the laboratory and found that they released large amounts of fructose into the bloodstream. The fructose, the scientists found, was transported into brain cells by molecular fructose pumps that in all other mammals are found only on cells of the intestine. “The naked mole-rat has simply rearranged some basic building-blocks of metabolism to make it super-tolerant to low oxygen conditions,” said Park, who has studied the strange species for 18 years. At oxygen levels low enough to kill a human within minutes, naked mole-rats can survive for at least five hours, Park said. They go into a state of suspended animation, reducing their movement and dramatically slowing their pulse and breathing rate to conserve energy. And they begin using fructose until oxygen is available again. The naked mole-rat is the only known mammal to use suspended animation to survive oxygen deprivation. The scientists also showed that naked mole-rats are protected from another deadly aspect of low oxygen – a buildup of fluid in the lungs called pulmonary edema that afflicts mountain climbers at high altitude. The scientists think that the naked mole-rats’ unusual metabolism is an adaptation for living in their oxygen-poor burrows. Unlike other subterranean mammals, naked mole-rats live in hyper-crowded conditions, packed in with hundreds of colony mates. With so many animals living together in unventilated tunnels, oxygen supplies are quickly depleted.


Deprived of oxygen, naked mole-rats can survive by metabolizing fructose just as plants do, researchers report this week in the journal Science. Understanding how the animals do this could lead to treatments for patients suffering crises of oxygen deprivation, as in heart attacks and strokes. "This is just the latest remarkable discovery about the naked mole-rat -- a cold-blooded mammal that lives decades longer than other rodents, rarely gets cancer, and doesn’t feel many types of pain," says Thomas Park, professor of biological sciences at the University of Illinois at Chicago, who led an international team of researchers from UIC, the Max Delbrück Institute in Berlin and the University of Pretoria in South Africa on the study. In humans, laboratory mice, and all other known mammals, when brain cells are starved of oxygen they run out of energy and begin to die. But naked mole-rats have a backup: their brain cells start burning fructose, which produces energy anaerobically through a metabolic pathway that is only used by plants – or so scientists thought. In the new study, the researchers exposed naked mole-rats to low oxygen conditions in the laboratory and found that they released large amounts of fructose into the bloodstream. The fructose, the scientists found, was transported into brain cells by molecular fructose pumps that in all other mammals are found only on cells of the intestine. “The naked mole-rat has simply rearranged some basic building-blocks of metabolism to make it super-tolerant to low oxygen conditions,” said Park, who has studied the strange species for 18 years. At oxygen levels low enough to kill a human within minutes, naked mole-rats can survive for at least five hours, Park said. They go into a state of suspended animation, reducing their movement and dramatically slowing their pulse and breathing rate to conserve energy. And they begin using fructose until oxygen is available again. The naked mole-rat is the only known mammal to use suspended animation to survive oxygen deprivation. The scientists also showed that naked mole-rats are protected from another deadly aspect of low oxygen – a buildup of fluid in the lungs called pulmonary edema that afflicts mountain climbers at high altitude. The scientists think that the naked mole-rats’ unusual metabolism is an adaptation for living in their oxygen-poor burrows. Unlike other subterranean mammals, naked mole-rats live in hyper-crowded conditions, packed in with hundreds of colony mates. With so many animals living together in unventilated tunnels, oxygen supplies are quickly depleted.


News Article | May 5, 2017
Site: www.engineeringnews.co.za

When Koos Smit studied civil engineering on a public service bursary at the University of Pretoria in the 1970s, the plan was that he would qualify and build dams and pipelines. However, an oversupply of engineers at the Department of Water Affairs saw him sign up at National Roads. He remained at National Roads, and its successors, for the next 43 years, managing the development and maintenance of roads instead. Smit will retire at the end of May, exiting the South African National Roads Agency Limited (Sanral) as the entity’s engineering executive. “I never regretted the decision to go National Roads. I have had some wonderful opportunities to grow as an engineer,” says Smit. For the first eight years of his career, he was part of internal supervisory teams that procured and directed the construction of three diverse greenfield projects in different parts of the country. He started off as an assistant resident engineer, and became a resident engineer midway through this period. The projects included the construction of 7 km of N1 concrete freeway between Fairlands and Main Reef road, at an estimated current value of R1.1-billion. Construction of this road included the relocation of 1.5 km of railway line carrying 600 000 commuters a day, as well as traversing a number of mine dumps, which had to be stabilised. Another project was the construction of the N3 dual carriageway between Umhlatuzana and Key Ridge, in KwaZulu-Natal, which comprised 3.5-million cubic metres of earthworks, with a single embankment size of 1.35-million cubic metres. To complicate matters further, an unexpected visitor, cyclone Domoina, wreaked havoc halfway through the project. After this eight-year period, Smit acted as engineer on the reconstruction of the Cradock to Cookhouse portion of the N10. He also managed the construction of greenfield projects on the Garden Route, as well as the North Coast toll road between Umhloti and Tinly Manor. Toll Roads In 1993, amid the political uncertainty in the build up to the change of government, Smit became involved with the proposed N1 toll road. “With the fast-growing growing traffic on the N1 in the 1990s, there was a dire need to extend the N1 from Middelfontein to Polokwane, but, as there were no funds from the fiscus and limited borrowing capacity as a result of a cap on the State guarantee, it was decided to develop this 126 km of freeway as a public–private partnership (PPP), with off-government balance sheet financing.” Legislation at the time, however, did not allow the private sector to collect tolls for its own account in order to construct and maintain the road, which meant the N1 tender was structured as a long-term performance contract in which government would collect the tolls. This provided a revenue stream on which the prospective tenderers had to tender to procure financing to construct and maintain the road, then transferring the road back to the State within the shortest possible repayment period. The shortest repayment period of 23 years tendered by the successful contractor, ends in October 2018. “Despite uncertainty in the markets and our failure to obtain off-government balance sheet financing it was still a very successful partnership.” says Smit. As a new government came to power in 1994, the responsibility for national roads was transferred to State-owned entity Sanral in 1998, with Smit joining the agency as engineering executive. The new government wanted to create job opportunities grow the economy through the development of infrastructure. This placed three identified spatial development corridors on the table, explains Smit. Toll road concessions – or upgrading of the roads through the user-pay principle – in the Maputo Development Corridor, the Platinum Corridor and the Durban-Gauteng Development Corridor saw financial close in less than six years. The combined initial construction cost of the three concession projects was R19-billion, at current rand value, with the combined estimated cost of maintenance and improvements over the 30-year concession period around R28-billion, also in current rand-value. “Our main challenge in the development of these projects was that there was very little or no experience of PPPs in government or the private sector at the time, nor any local guidelines or regulations,” says Smit. “We had to start from scratch to carve out a concessions template that would suit the South African environment.” Gauteng Toll Roads Smit says he made “a modest contribution in the procurement methodology, as well as conceptualisation, structuring and procurement of the toll system service providers” of the Gauteng Freeway Improvement Project (GFIP), which led to the implementation of electronic tolling (e-tolling) on 200 km of Gauteng’s urban highways. The project has faced much resistance from users, with compliance rates well below initial forecasts. Political will and public acceptance are the main pre-requisites for an enabling environment to develop toll roads. “I believe GFIP would have been a global flagship project if procured in a less complex enabling environment,” says Smit. Smit says Sanral still has R120-billion of possible toll roads on its books, but warns that these projects will now have to join a long waiting list for Sanral’s non-toll budget. Highlighting another challenge he faced in his career, he expressed his disappointment that the De Beer’s pass project, as a second route over the Drakensberg mountain range, has not been approved. “It would have been of huge benefit to the economy of South Africa.” Instead of building the De Beer’s pass, Sanral has opted to upgrade the existing alignment between Keeversfontein and Warden. Core Function Despite the large projects that have marked Smit’s career, he describes the task of developing and maintaining South Africa’s national road network as his core function. “It is about the optimal investment of our non-toll budget of around R15-billion a year and the procurement of around 450 service providers on an annual basis in order to develop and maintain our road network. Overseeing the delivery cycle is where most of my energy goes, and there is no glory there, only hard work.” He adds that nothing he has achieved at Sanral has been a “one-man show”. “It is a huge team effort to procure and manage service providers to develop and maintain the national road network.” No successor has been named for Smit yet. He notes that he will do some consulting work upon leaving the Sanral office for the last time as engineering executive.


Nel L.H.,University of Pretoria
Emerging Infectious Diseases | Year: 2013

Human rabies is an ancient disease but in modern times has primarily been associated with dog rabies-endemic countries of Asia and Africa. From an African perspective, the inevitable and tragic consequences of rabies require serious reflection of the factors that continue to drive its neglect. Established as a major disease only after multiple introductions during the colonial era, rabies continues to spread into new reservoirs and territories in Africa. However, analysis of reported data identified major discrepancies that are indicators of poor surveillance, reporting, and cooperation among national, international, and global authorities. Ultimately, the absence of reliable and sustained data compromises the priority given to the control of rabies. Appropriate actions and changes, in accordance to the One Health philosophy and including aspects such as synchronized, shared, and unified global rabies data reporting, will not only be necessary, but also should be feasible.


Grant
Agency: GTR | Branch: NERC | Program: | Phase: Research Grant | Award Amount: 456.50K | Year: 2016

The cooling of poly-component liquids, such as magma (and also ice-cream and salt- or sea-water), can drive solidification in a bewildering array of styles. Often the solid that forms is of a different composition from the liquid (e.g. pure ice from salt water). This means that the composition and temperature of the residual liquid is always changing during cooling, causing changes in the density of the liquid. These density changes can drive convection in the liquid, and can have profound effects on the way in which mass and heat are transported within the crystallising system. When cooling rates are gentle solidification occurs from the cold boundaries as when ice forms on the pond on a still winters day. In contrast, when cooling rates are very high, vigorous convection in the liquid can drive crystallization away from the cold boundaries, forming a flurry of crystallization in the swirling interior. In the context of bodies of molten rock (magma) the way convective motion can re-distribute mass has significant effects on the way the residual liquid changes composition. This plays a vital role in determining the final composition (and hence the explosivity) of any erupted lava flows. The style of crystallization also affects how quickly a magma conduit feeding a surface eruption will freeze sufficiently to prevent more magma travelling along it. A further important reason to understand how convection controls the way magmas evolve in crustal magma chambers is because the only way we can make deductions about processes occurring in the inaccessible deep Earth is by an examination of the composition of erupted lavas. The project will involve creating small-scale, bench-top analogues for real magma bodies using salt-water solutions. We will be able to control the cooling and solidification rates in our tanks and watch directly what happens and where the crystals are forming - something that is not possible in real magmas. We will compare our experimental results with natural examples of basaltic, magmatic intrusions by taking advantage of some recent new discoveries that mean we can decode the record of crystallization style left in fully-solidified basaltic intrusions and flows using details of grain shape, internal compositional variations and the spatial distribution of dense minerals. These microstructural markers will enable us to work out whether the liquid in the magma bodies convected or was static during solidification. These discoveries provide an exciting opportunity to make real progress in understanding the fundamental processes at work as these bodies cooled.

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