The University of Cape Town is a public research university located in Cape Town in the Western Cape province of South Africa. UCT was founded in 1829 as the South African College, and is the oldest university in South Africa and the second oldest extant university in Africa. The language of instruction is English. Wikipedia.
Background: Anorexia Nervosa (AN) is a debilitating, sometimes fatal eating disorder (ED) whereby restraint of appetite and emotion is concomitant with an inflexible, attention-to-detail perfectionist cognitive style and obsessive-compulsive behaviour. Intriguingly, people with AN are less likely to engage in substance use, whereas those who suffer from an ED with a bingeing component are more vulnerable to substance use disorder (SUD). Discussion: This insight into a beneficial consequence of appetite control in those with AN, which is shrouded by the many other unhealthy, excessive and deficit symptoms, may provide some clues as to how the brain could be trained to exert better, sustained control over appetitive and impulsive processes. Structural and functional brain imaging studies implicate the executive control network (ECN) and the salience network (SN) in the neuropathology of AN and SUD. Additionally, excessive employment of working memory (WM), alongside more prominent cognitive deficits may be utilised to cope with the experience of negative emotions and may account for aberrant brain function. Summary: WM enables mental rehearsal of cognitive strategies while regulating, restricting or avoiding neural responses associated with the SN. Therefore, high versus low WM capacity may be one of the factors that unites common cognitive and behavioural symptoms in those suffering from AN and SUD respectively. Furthermore, emerging evidence suggests that by evoking neural plasticity in the ECN and SN with WM training, improvements in neurocognitive function and cognitive control can be achieved. Thus, considering the neurocognitive processes of excessive appetite control and how it links to WM in AN may aid the application of adjunctive treatment for SUD. © 2016 Brooks. Source
Current Allergy and Clinical Immunology
The World Allergy Organization (WAO) White Book on Allergy presents an up-to-date review of the specialty of allergology from a global perspective. This book is of great importance and relevance for the practice of allergology in South Africa. It is of particular interest at this momentous time in the history of allergology in this country. Allergology has just been recognised as a subspecialty of internal medicine, paediatrics and general practice. Source
Anderson P.M.L.,UCT |
O'Farrell P.J.,South African Council for Scientific and Industrial Research
Ecology and Society
Rapid global urbanization and the knowledge that ecological systems underpin the future sustainability and resilience of our cities, make an understanding of urban ecology critical. The way humans engage with ecological processes within cities is highly complex, and both from a social and ecological perspective these engagements cannot be interpreted meaningfully on the basis of a single timeframe. Historical analyses offer useful insights into the nature of social-ecological interactions under diverse conditions, enabling improved decision-making into the future. We present an historical review of the evolving relationship between the urban settlement of Cape Town and the ecological processes inherent to its natural surroundings. Since its establishment, the people of Cape Town have been acutely aware of, and exploited, the natural resources presented by Table Mountain and its surrounding wilderness area. An examination of this pattern of engagement, explored through an ecological process lens, in particular drawing on the terminology provided by the ecosystem services framework, reflects a journey of the changing needs and demands of a growing urban settlement. Ecological processes, and their ensuing flow of ecosystem services, have been exploited, overexploited, interrupted, reestablished, conserved, and variably valued through time. Processes of significance, for example water provision, soil erosion, the provision of wood and natural materials, and the role of fire, are presented. This historical analysis documents the progression from a wilderness to a tamed and largely benign urban environment. Evident is the variable valuing of ecosystem service attributes through time and by different people, at the same time, dependent on their immediate needs. © 2012 by the author(s). Source
News Article | April 13, 2016
A mysterious alignment has been witnessed in a remote area of the universe. Sixty-four supermassive black holes have been observed to be spinning out radio jets from their centers, all pointing towards the same direction. Black holes are well known to emit radio emissions. However, this is the first time their alignment is of such a great magnitude. This phenomenon implies that the force governing these black holes is much greater and older, hence the alignment has been linked to "primordial mass fluctuations" in the early universe. "Since these black holes don't know about each other, or have any way of exchanging information or influencing each other directly over such vast scales, this spin alignment must have occurred during the formation of the galaxies in the early universe," said Professor Andrew Russ Taylor, joint UWC/UCT SKA Chair, Director of the recently launched Inter-University Institute for Data Intensive Astronomy, and principal author of the Monthly Notices study. The astronomers have been puzzled over this alignment and have speculated a few theories that could have been responsible for triggering this large scale phenomenon. Few of the speculated theories include cosmic strings – theoretical fault lines in the universe, exotic particles like axions or cosmic magnetic fields, or maybe something entirely different altogether, which is yet to be ascertained. Experts said the recent observation of black hole alignment could provide evidence of the environmental influences that contributed to the formation and evolution of galaxies as well as the primordial fluctuations that brought about the structure of the universe. This strange phenomenon was captured as a result of three years of deep radio imaging carried out by the Giant Metrewave Radio Telescope (GMRT) located in India. The alignment may hold clues about the early universe when the black holes had initially formed. The study was published in the Monthly Notices of the Royal Astronomical Society. © 2016 Tech Times, All rights reserved. Do not reproduce without permission.
An international team of scientists, including groups from UC San Francisco, Gladstone Institutes, and the University of Cape Town (UCT), South Africa, have for the first time identified genes and gene regulatory elements that are essential in wing development in the Natal long-fingered bat (Miniopterus natalensis), a species widely distributed in eastern and southern Africa. The new research — presented in two papers published on March 28, one in Nature Genetics and one in PLoS Genetics — revealed regulatory switches that turn bat genes on and off at crucial times during limb development, and has implications for understanding how differences in the size, shape and structure of limbs are generated in mammals in general, including humans, the researchers said. “This gives us our first detailed picture of the genomics behind bat wing development,” said co-senior investigator Nadav Ahituv, Ph.D., a UCSF associate professor of bioengineering and therapeutic sciences in the UCSF School of Pharmacy and member of the UCSF Institute for Human Genetics, whose lab also studies the genetics of human limb malformations. “While some attempts have been made to identify the molecular events that led to the evolution of the bat wing, these have been primarily done on a ‘gene by gene’ basis. In contrast, this work lays out a genome-wide blueprint for the causes that led to the development of the bat wing, a key evolutionary innovation that contributed to bats becoming the second most diverse order of mammals.” Bats are the only mammals capable of powered flight — an innovation that is thought to have occurred about 50 million years ago. Biologists since Charles Darwin have used the structure of the bat wing as an example of both evolutionary novelty — the appearance of a new trait — and vertebrate homology, or shared ancestry between two seemingly different structures — in this case, the wing of the bat and the forelimb of other mammals. But the path of bats’ unique evolution is unclear, noted Nicola Illing, Ph.D., co-senior investigator in the Department of Molecular and Cell Biology at UCT. “The fossil record does not show the transition from tree-climbing mammals with short, free digits to ones that have elongated fingers supporting a wing,” Illing said. “Until now, scientists knew very little about how genes are turned on and off during bat embryonic development to transform a mammalian forelimb into a wing.” In the Nature Genetics paper, the scientists, including co-lead authors Walter L. Eckalbar, Ph.D., a postdoctoral fellow in Ahituv’s laboratory at UCSF, and Ph.D. student Stephen Schlebusch of UCT, first sequenced the entire genome of the Natal long-fingered bat. They then performed detailed molecular genomic analysis on bat embryos collected by Illing and her research group at the de Hoop Nature Reserve in South Africa. The researchers identified over 7,000 genes that are expressed differently in forelimbs compared with hindlimbs at three key stages of bat wing development. They found that many signaling pathways are activated differentially as well, including pathways important in limb formation, digit growth, long bone development and cell death. Also expressed differently are many proteins associated with ribosomes – molecular machines found in all cells that are responsible for protein production during limb development. “It took bats millions of years to evolve wings,” said Eckalbar. “Our work shows that they did this through thousands of genetic alterations, involving both genes used by all animals during limb development and genes whose usage in limb development may be unique to bats.” In addition, the scientists found thousands of genetic switches, called enhancers, which regulate the timing and levels of gene expression and show differences in activity between forelimbs and hindlimbs at these key stages of wing development. “Importantly, this work identified not just which genes are expressed at what stage of growth, but the genetic switches in the genome that are responsible for turning those genes on and off,” Ahituv said. In the study published in PLoS Genetics, the research team, including co-lead authors Betty M. Booker, Ph.D., a post-doctoral fellow in Ahituv’s laboratory, and Tara Friedrich, a Ph.D. student at UCSF and Gladstone Institutes, searched for the evolutionary origin of the bat wing. “We identified genomic sequences that have not changed in most vertebrates, but experienced rapid changes in the common ancestor of today’s bats,” explained Friedrich, a member of the laboratory of co-senior investigator Katherine S. Pollard, Ph.D., a senior investigator at the Gladstone Institutes, a UCSF professor of epidemiology and biostatistics, and a member of the UCSF Institute for Human Genetics. The team mapped these so-called “bat accelerated regions” (BARs) onto areas that were predicted to be important switches that turn genes on during limb development, and found 166 BARs with the potential to influence bat wing development. The researchers tested the effects of five of these BARs in genetically modified mouse embryos and found that all five bat sequences were capable of switching on a reporter gene in the developing mouse forelimb. They noted that one region, BAR116, is located near the HoxD genes, which are known to be involved in limb patterning and skeletal growth. Previously, Mandy Mason, a Ph.D. student at UCT, had shown that two of the HoxD genes — Hoxd10 and Hoxd11 — are far more active in bat wings compared to bat legs during their embryonic development. Following up these lines of evidence, the researchers showed that the bat BAR116 sequence appears to function as a genetic switch that is active in developing limbs, in particular the forelimbs, while the equivalent mouse sequence did not show any activity. “Our computational method enabled identification of DNA sequences that changed dramatically during the emergence of bats,” said Pollard. “It is exciting to see that this evolutionary signature pointed us to parts of the mammalian genome that control limb development.” In addition to unveiling new fundamental details of the evolutionary and developmental origins of powered flight in bats, the new research may provide broader insights into the biological processes that control how mammalian limbs develop in general, Ahituv said. “Importantly, this work will increase our understanding of how alterations in limb development could lead to limb malformations in humans,” he said. “Potentially, it could eventually help contribute to the development of tools and techniques to prevent such malformations.”