New technology allows scientists first glimpse of intricate details of Little Foot’s life
- Wits University
High resolution X-ray imaging of Little Foot's skull and dentition shows Little Foot suffered periods of dietary stress and illness when she was a child.
In June 2019, an international team, including researchers from Wits University, took the complete skull of the 3.67-million-year-old ‘Little Foot’ Australopithecus skeleton, from South Africa to the UK and achieved unprecedented imaging resolution of its bony structures and dentition in an X-ray synchrotron-based investigation at the UK’s national synchrotron, Diamond Light Source.
The X-ray work is highlighted in a new paper in e-Life, published today (2nd March 2021) focusing on the inner craniodental features of ‘Little Foot’. The remarkable completeness and great age of the ‘Little Foot’ skeleton makes it a crucially important specimen in human origins research and a prime candidate for exploring human evolution through high-resolution virtual analysis.
To recover the smallest possible details from a fairly large and very fragile fossil, the team decided to image the skull using synchrotron X-ray micro computed tomography at the I12 beamline at Diamond, revealing new information about human evolution and origins. This paper outlines preliminary results of the X-ray synchrotron-based investigation of the dentition and bones of the skull (i.e., cranial vault and mandible).
Leading author and Principal Investigator, Dr Amélie Beaudet, Department of Archaeology, University of Cambridge and honorary researcher at the University of the Witwatersrand (Wits University) explains: “We had the unique opportunity to look at the finest details of the craniodental anatomy of the ‘Little Foot’ skull. While scanning it, we did not know how well the smallest structures would be preserved in this individual, who lived more than 3.5 million years ago. So, when we were finally able to examine the images, we were all very excited and moved to see such intimate details of the life of ‘Little Foot’ for the first time. The microstructures observed in the enamel indicate that Little Foot suffered through two clear periods of dietary stress or illness when she was a child.”
The team was also able to observe and describe the vascular canals that are enclosed in the compact bone of the mandible. These structures have the potential to reveal a lot about the biomechanics of eating in this individual and its species, but also more broadly about how bone was remodelled in ‘Little Foot’. The branching pattern of these canals indicates some remodelling took place, perhaps in response to changes in diet, and that Little Foot died as an older individual.
The team also observed tiny (less than 1 mm) channels in the braincase that are possibly involved in brain thermoregulation (how to cool down the brain). Brain size increased dramatically throughout human evolution (about threefold), and, because the brain is very sensitive to temperature change, understanding how temperature regulation evolves is of prime interest.
Dr Amélie Beaudet adds: “Traditionally, none of these observations would have been possible without cutting the fossil into very thin slices, but with the application of synchrotron technology there is an exciting new field of virtual histology being developed to explore the fossils of our distant ancestors.”
Dr Thomas Connolley, Principal Beamline Scientist at Diamond commented:
“足球竞彩app排名 aspects of early hominin biology remain debated, or simply unknown. In that context, synchrotron X-ray imaging techniques like microtomography have the potential to non-destructively reveal crucial details on the development, physiology, biomechanics and taxonomy of fossil specimens. Little Foot’s skull was also scanned using the adjacent IMAT neutron instrument at ISIS Neutron and Muon Source, combining X-ray and neutron imaging techniques in one visit to the UK. With such a rich volume of information collected, we’re eager to make more discoveries in the complementary X-ray and neutron tomography scans.”
Applications of X-ray synchrotron-based analytical techniques in evolutionary studies have opened up new avenues in the field of (paleo)anthropology. In particular, X-ray synchrotron microtomography has proved to be enormously useful for observing the smallest anatomical structures in fossils that are traditionally only seen by slicing through the bones and looking at them under a microscope.
Through the last decade, there have been more studies in palaeoanthropology using synchrotron radiation to investigate teeth and brain imprints in fossil hominins. However, scanning a complete skull such as the one of ‘Little Foot’ and aiming to reveal very small details using a very high-resolution was quite challenging, but the team managed to develop a new protocol that made this possible. To recover the smallest possible details from a fairly large and very fragile fossil, the team decided to image the skull using synchrotron X-ray micro computed tomography at the I12 beamline at Diamond.
Principal Investigator, and Associate Professor, Prof Dominic Stratford, University of Witwatersrand (Wits University), School of Geography, Archaeology and Environmental Studies says: “This level of resolution is providing us with remarkably clear evidence of this individual’s life. We think there will also be a hugely significant evolutionary aspect – as studying this fossil in this much detail will help us understand which species she evolved from and how she differs from others found at a similar time in Africa. This is just our first paper so watch this space. Funding permitting, we hope to be able to bring other parts of ‘Little Foot’ to Diamond,” adding:
“This research was about bringing ‘the best-preserved Australopithecus skull to the ‘best of the best’ synchrotron facility for our purposes. Traditionally, hominins have been analysed by measuring and describing by the exterior shapes of their fossilised bones to assess how these differ between species. Synchrotron development and microCT resources means that we are now able to virtually observe structures inside the fossils, which hold a wealth of information. More recently, technology has developed to such an extent that we can now virtually explore minute histological structures in three dimensions, opening new avenues for our research.”
The first bones of the ‘Little Foot” fossil were discovered in the Sterkfontein Caves, northwest of Johannesburg, by Professor Ron Clarke of the University of the Witwatersrand in 1994. In 1997, following their discovery of the location of the skeleton, Professor Clarke and his team spent more than 20 years painstakingly removing the skeleton in stages from the concrete-like cave breccia using a small airscribe (a vibrating needle). Following cleaning and reconstructing, the skeleton was publicly unveiled in 2018. Wits University is the custodian of the StW 573, ‘Little Foot’, fossil.
Professor Ron Clarke, the British scientist based at Wits University in South Africa who discovered and excavated ‘Little Foot’ and conducted all the early examinations of the fossil, was also part of the research team and concludes: “It has taken us 23 years to get to this point. This is an exciting new chapter in ‘Little Foot’s’ history, and this is only the first paper resulting from her first trip out of Africa. We are constantly uncovering new information from the wealth of new data that was obtained. We hope this endeavour will lead to more funding to continue our work. Our team and PAST emphasise that all of humanity has had a long-shared ancestry in harmony with the natural world, and that learning from those earliest ancestors gives us perspective on the necessity to conserve nature and our planet.”
Prehistoric killing machine exposed
- Wits University
Previously thought of as heavy, slow and sluggish, the 260-million-year-old predator, Anteosaurus, was a ferocious hunter-killer.
Judging by its massive, bone-crushing teeth, gigantic skull and powerful jaw, there is no doubt that the Anteosaurus, a premammalian reptile that roamed the African continent 265 to 260 million years ago – during a period known as the middle Permian – was a ferocious carnivore.
However, while it was previously thought that this beast of a creature – that grew to about the size of an adult hippo or rhino, and featuring a thick crocodilian tail – was too heavy and sluggish to be an effective hunter, a new study has shown that the Anteosaurus would have been able to outrun, track down and kill its prey effectively.
Despite its name and fierce appearance, Anteosaurus is not a dinosaur but rather belongs to the dinocephalians—mammal-like reptiles predating the dinosaurs. Much like the dinosaurs, dinocephalians roamed and ruled the Earth in the past, but they originated, thrived, and died about 30 million years before the first dinosaur even existed.
The fossilised bones of Dinocephalians are found in many places in the world. They stand out by their large size and heavy weight. Dinocephalian bones are thick and dense, and Anteosaurus is no exception. The Anteosaurus’ skull was ornamented with large bosses (bumps and lumps) above the eyes and a long crest on top of the snout which, in addition to its enlarged canines, made its skull look like that of a ferocious creature. However, because of the heavy architecture of its skeleton, it was previously assumed that it was a rather sluggish, slow-moving animal, only capable of scavenging or ambushing its prey, at best.
“Some scientists even suggested that Anteosaurus was so heavy that it could only have lived in water,” says Dr Julien Benoit of the Evolutionary Studies Institute at the University of the Witwatersrand (Wits University).
By carefully reconstructing the skull of the Anteosaurus digitally using X-ray imaging and 3D reconstructions, a team of researchers investigated the internal structures of the skull and found that the specific characteristics of its brain and balance organs were developed in such a way that it was everything but slow-moving.
“Agile predators such as cheetahs or the infamous Velociraptor have always had a very specialised nervous systems and fine-tuned sensory organs that enable them to track and hunt down prey effectively,” says Benoit. “We wanted to find out whether the Anteosaurus possessed similar adaptations.”
The team found that the organ of balance in Anteosaurus (its inner ear) was relatively larger than that of its closest relatives and other contemporaneous predators. This indicates that Anteosaurus was capable of moving much faster than its prey and competitors. They also found that the part of the brain responsible for coordinating the movements of the eyes with the head was exceptionally large, which would have been a crucial trait to ensure the animal’s tracking abilities.
“In creating the most complete reconstruction of an Anteosaurus skull to date, we found that overall, the nervous system of Anteosaurus was optimised and specialised for hunting swiftly and striking fast, unlike what was previously believed,” says Dr Ashley Kruger from the Natural History Museum in Stockholm, Sweden and previously from Wits University.
“Even though Anteosaurus lived 200-million years before the famous dinosaur Tyrannosaurus rex, Anteosaurus was definitely not a ‘primitive’ creature, and was nothing short of a mighty prehistoric killing machine,” says Benoit.
Wits and Biovac partner to develop skills to produce viral vectored vaccines in South Africa
- Wits University
The Antiviral Gene Therapy Research Unit via Wits Enterprise has partnered with Biovac to develop the skills capacity to produce viral vectored vaccines in SA.
Demonstrating that South Africa has the capability and the skills resources to tackle serious health problems, Wits University’s Antiviral Gene Therapy Research Unit (AGTRU), with Wits Commercial Enterprise acting on its behalf, partnered with Cape Town based bio-pharmaceutical company, Biovac, in a partnership announced on 2 March 2021.
Wits Enterprise is a private company wholly owned by Wits University and mandated to promote and commercialise Wits’ intellectual capital, research and innovations, so as to broaden and deepen the University's societal impact.
AGTRU has specialised expertise in advancing gene therapy for viral infections. Viruses can be genetically engineered for gene therapy to treat genetic diseases, viral infections, develop vaccines and boost immunity.
Wits' team specialises in the engineering, propagation and assay of adenoviruses, which as carriers (vectors) of genes encoding immunogenic proteins, are gaining favour in the production of viral vectored vaccines including vaccines against COVID-19.
“Our team’s ability to engineer, propagate, purify and assay the engineered viruses is a highly specialised technology. To the best of our knowledge, the Wits/SAMRC facility is the only one with expertise in this technology in the country, and perhaps the continent,” says Personal Professor Patrick Arbuthnot, Director of AGTRU.
Viral vector-based vaccines are different from most conventional vaccines in that they use the body’s cells to produce antigens. The modified virus is capable of carrying the genetic code for the antigen into many different types of cells, including those of humans, which are then instructed to make large amounts of antigen. This triggers an intended immune response to fight the pathogen (fir example, SARS-CoV-2).
Arbuthnot explains: “The genetic material of the virus - DNA in the case of adenoviruses - is modified by removing some of the viral genes. These are replaced with the DNA coding of an immunity-causing protein, such as the spike protein of the SARS Coronavirus-2 that causes COVID-19. The virus itself is harmless and by stimulating cells to produce antigens, can safely promote an immune response.
As a safety precaution, engineered viruses are replication-incompetent. This means that they cannot produce new viruses in a person receiving the vaccine and they can only proliferate in a laboratory-controlled setting where the deficiencies of the engineered virus are complemented in the cells producing the virus.”
The Wits team will assist with building specialist skills capacity within Biovac to generate engineered viruses that may be used as COVID-19 and other vaccines, according to Arbuthnot.
“We have confidence that the collaboration will facilitate an enhanced capability and readiness for future production of active pharmaceutical ingredient/drug substances for vaccines targeted at viruses such as SAR-CoV-2 in South Africa. If successful, it will be a good example of how leveraging South African partnerships to tap into specialist resources can address South Africa’s preparedness for future disease outbreaks. It will also be an endorsement of the government’s investment in basic research in South Africa,” he adds.
Biovac is a bio-pharmaceutical company based in Cape Town that is the result of a partnership formed with the South African government in 2003 to establish local vaccine manufacturing capability for the provision of vaccines. The company started its journey of building manufacturing capability by following a reverse integration approach wherein it has been importing, exporting, formulating, filling packaging, testing and supplying vaccines. Biovac currently supplies over 15 million doses of vaccines via its cold and supply chain infrastructure.
Commenting on the partnership with the Wits/ South African Medical Research Council (SAMRC) Antiviral Gene Therapy Research Unit, Dr Morena Makhoana, Biovac CEO, says: “South Africa desperately needs to build capability to manufacture viral vaccines from scratch rather than importing the API [active pharmaceutical ingredient]. Biovac has built capability in formulation and filling of vaccines and this partnership, utilizing the skills transfer from Wits, is an excellent start to building the know-how to produce viral vectored vaccines. It’s part of Biovac’s reverse integration strategy towards building end-to-end vaccine manufacturing capability.”
Whale and dolphin brains are special, but for heat production, not for intelligence
- Wits University
Scientific evidence shows specialised features in the large brains of whales and dolphins that are adapted for heat production.
Whales and dolphins have the largest brains on the planet, some of them weighing over eight kilogrammes, six times heavier than the average human brain.
These mammals’ huge brains have often been cited as evidence of them being highly intelligent; however, does their large brain size mean they have the same mental – or better – capabilities as humans?
Scientific evidence from a study led by Professor Paul Manger from the School of Anatomical Sciences at the University of the Witwatersrand in Johannesburg, South Africa (Wits University), indicate that whales and dolphins’ large brains lack the diversity, flexibility and adaptability in their mental processes and behaviour that humans have, and that their large brains instead evolved to keep these brains warm in icy oceanic temperatures. This research has been published in the journal Scientific Reports.
“In water, mammals lose heat to the environment 90 times faster than we do to the air,” says Manger. “The brains of all mammals produce heat independently of the heat-producing mechanisms of the body. This heat is required to keep their neurons warm enough to function efficiently.”
Whale and dolphin brains became exceptionally large around 32-million-years ago, 20 million years after they became fully aquatic and around the time when there was a major drop in oceanic water temperatures across the planet.
Even a small drop in brain temperature makes many neurons inactive, greatly reducing mental activity. Manger and his team proposed that if changes in water temperature led to the emergence of large brains in whales and dolphins, then there should be a specialised brain-based heat producing system in whales and dolphin brains, not seen in the brains of other mammals.
“What we have found is that most of the cells forming the brains of whales and dolphins have the internal chemistry required to function as the brain’s own heating elements,” says Manger, who first proposed in 2006 that the large size of brains in whales and dolphins is an adaptive evolutionary response to the challenges of living in the cold aquatic environment. “These ‘heating elements’ are far fewer in the brains of land-living mammals, such as the closely related hippopotamuses, pigs, buffaloes, camels, and antelopes.”
Manger and his colleagues found that there are three unusual, or specialised, features of a brain-based heat production system in whale and dolphin brains. Firstly, they found that around 90% of the neurons in whale and dolphin brains contain proteins called uncoupling proteins. These proteins make energy generation in cells very inefficient, giving off heat instead of producing the ATP required for normal neuronal functions. In closely related species, such as the river hippopotamus, a mere 35% of neurons contain these proteins.
Secondly, in whales and dolphins, 30-70% of glial cells, the cells that support neuronal function, contain uncoupling proteins. In other closely related species, these glial cells do not appear to contain uncoupling proteins in readily detectable amounts.
Finally, the nerve terminals that contain the neurochemical noradrenaline, which controls the concentration and activity of uncoupling proteins, are about 30% denser in whale and dolphin brains when compared to closely related species.
“These new findings, when merged with our current understanding of the structure and function of whale and dolphin brains, indicate that their brains are specialised for thermogenesis, probably in response to their cold aquatic environment, rather than for intellectual functions,” says Manger.
While the concept that whales and dolphins do not appear to be any more intelligent than the average mammal might be a sobering thought for some, Manger and his team believe it is crucial for conservation purposes to understand these unique mammals for what they really are, rather than for what we might imagine, or wish, them to be.
“Knowing how central water temperature is to their survival may allow us to understand what will happen to certain species of whale and dolphin during the inevitable rise in oceanic temperatures associated with human-induced climate change,” says Manger.
“It is quite possible that some species may die through overheating, becoming victims of global warming. This understanding may allow us to direct our efforts in the most appropriate way to secure the future of as many whale and dolphin species as possible.”
Novavax 足球竞彩app排名 vaccine trial results in SA and UK confirm high levels of efficacy
- Wits University
Results of the Novavax 足球竞彩app排名 vaccine trial in SA and UK have confirmed high levels of efficacy against the original and variant 足球竞彩app排名.
The results show 100% protection against severe disease in both the SA and the UK trials.
Results announced today also showed efficacy against variants circulating in SA and the UK.
An updated analysis of the Novavax vaccine trial in South Africa shows vaccine efficacy of 55.4% against mainly mild 足球竞彩app排名 among HIV-negative trial participants, in a country where the vast majority of strains are B.1.351 escape variants.
In addition, protection against severe disease due to the B.1.351 variant dominating in South Africa was 100%, with all 足球竞彩app排名 hospitalization and deaths having occurred in the placebo group.
Professor Shabir Madhi, Executive Director of the Wits Vaccines and Infectious Diseases Analytics (VIDA) Research Unit, leads the Novavax 足球竞彩app排名 vaccine trial in South Africa.
“The results from the South African trial reinforce that, even with the evolution of the SARS-CoV-2 virus developing mutations in an attempt to evade immune responses induced following natural infection by ancestry virus, the first generation of 足球竞彩app排名 vaccines still offer great potential especially in mitigating severe disease and death from 足球竞彩app排名.
This was evident in South Africa where all the cases of 足球竞彩app排名 hospitalization and death occurred in the unvaccinated control group. This despite the effectiveness of the first generation 足球竞彩app排名 vaccines being variably affected in reducing the risk of mild 足球竞彩app排名 caused by the B.1.351 variant, due to the variant being relatively resistant to the antibody induced by all 足球竞彩app排名 vaccines.”
In a separate study of the Novavax 足球竞彩app排名 vaccine in the UK, efficacy was 96.4% against the original virus strain and 86.3% against the B.1.1.7/501Y.V1 variant circulating in the U.K (post hoc).
These updated final analyses build on the successful interim results announced in January 2021, adding substantially more 足球竞彩app排名 cases and statistical power in both studies.
In both the SA and UK trials, these analyses showed that the vaccine is well-tolerated, with low levels of severe, serious and medically attended adverse events at day 35, balanced between vaccine and placebo groups.
“We are very encouraged by the data showing that NVX-CoV2373 not only provided complete protection against the most severe forms of disease, but also dramatically reduced mild and moderate disease across both trials. 足球竞彩app排名ly, both studies confirmed efficacy against the variant strains,” said Stanley C. Erck, President and Chief Executive Officer, Novavax.
足球竞彩app排名 the South African Novavax 足球竞彩app排名 vaccine trial
The South Africa trial was a randomized, observer-blinded, placebo-controlled Phase 2b clinical trial.
One cohort evaluated efficacy, safety and immunogenicity in approximately 2 665 healthy adults.
The second cohort evaluated safety and immunogenicity in approximately 240 medically stable, HIV- positive adults.
A complete analysis of vaccine efficacy among 147 PCR-positive cases (51 cases in the vaccine group and 96 in the placebo group) demonstrated an overall efficacy of 48.6% with majority of illness being mild or moderate.
The vast majority of cases during the efficacy analysis were due to the B.1.351/501Y.V2 variant circulating in South Africa. All five cases of severe disease observed in the trial occurred in the placebo group. Among HIV-negative participants, 55.4% efficacy was observed.
The complete analysis shows that vaccine-induced protection began 14 days after dose 1, although increased efficacy was observed seven days after dose 2, the primary endpoint for the study.
A previously reported initial analysis from the study through 60 days indicated that prior infection with the original 足球竞彩app排名 strain might not completely protect against subsequent infection by the variant predominantly circulating in South Africa.
However, the complete analysis of the South Africa trial indicates that there may be a late protective effect of prior exposure with the original 足球竞彩app排名 strain. In placebo recipients, at 90 days the illness rate was 7.9% in baseline seronegative individuals, with a rate of 4.4% in baseline seropositive participants.
Madhi says: “As a benefit to the study volunteers, without whose selfless contribution this important study would not have been possible, we now plan to offer all of them the Novavax vaccine so they can be protected immediately against mild – and more importantly – severe 足球竞彩app排名 being caused by the B.1.351 variant.”
South African Oxford AstraZeneca 足球竞彩app排名 vaccine study a global game-changer
- Wits University
Findings of the SA study in the Oxford AstraZeneca 足球竞彩app排名 vaccine trial have been published in the New England Journal of Medicine (NEJM).
The NEJM, which published the study on 16 March 2021 following peer review, is the leading medical journal globally.
This is a landmark study in so far as being the first to raise the alarm that, despite early successes with 足球竞彩app排名 vaccines, further research is warranted on a next generation of 足球竞彩app排名 vaccines.
The results from this study, however, only indicate that the AstraZeneca vaccine does not have at least 60% efficacy against mild-moderate 足球竞彩app排名 due to the B.1.351 (N501Y.V2) variant.
Based on a broader body of evidence, the World Health Organization recommends that this vaccine still be deployed in countries where the B.1.351 variant circulates, as it likely still protects against severe infection, hospitalisation, and death caused by 足球竞彩app排名.
Professor Shabir Madhi, Executive Director of the Vaccines and Infectious Diseases Analytics (VIDA) Research Unit at the University of the Witwatersrand, Johannesburg, led the trial in South Africa:
“Despite the disappointing finding that the AstraZeneca vaccine did not protect against mild Covid infection because of the B.1.351 variant first identified in South Africa, peer review and publication of our research validates the findings and makes a compelling case for the development of a second-generation vaccines worldwide,” says Madhi.
First-generation vaccines refer to those designed to respond to the original SARS-CoV-2 virus. Second-generation vaccines refer to technology and design innovations that can provide protections against the constantly evolving variants that cause 足球竞彩app排名 disease.
A rapid response to variant reality
The findings of this study were previously publicised as a preprint on Sunday, 7 February 2021, and concluded that the ChAdOx1 nCoV-19 vaccine provided minimal protection against mild to moderate 足球竞彩app排名 infection from the B.1.351 coronavirus variant first identified in South Africa in mid-November 2020.
Prior to the evolution of the B.1.351 and P.1 variants, the South African National Department of Health (NDOH) had ordered and taken delivery of approximately one million doses of the Oxford AstraZeneca vaccine on 1 February 2021, after a published pooled analysis of this vaccine in December 2020 showed an overall vaccine efficacy of 66.7% in the UK and Brazil.
“We were in a state of euphoria about the high efficacy of several 足球竞彩app排名 vaccines against the original virus, but then the AstraZeneca study threw us a curve-ball,” says Madhi. “In this study now published in NEJM, we found that two doses of ChAdOx1 nCoV19 had no efficacy against non-hospitalized mild to moderate 足球竞彩app排名, mainly due to the B.1.351 variant.”
What the SA study published in NEJM reveals
The randomised, multi-centre, double-blinded trial enrolled 2026 participants between 24 June and 9 November 2020.
The trial was a phase 1b/11 trial that aimed to evaluate the safety, immunogenicity, and efficacy of the AstraZeneca vaccine ChAdOx1 nCoV19 in preventing symptomatic 足球竞彩app排名. Immunogenicity refers to the ability of a foreign substance, such as an antigen, to provoke an immune response. Vaccine efficacy refers to the percentage reduction of a disease in a clinical trial.
“A trial enrolling just 2026 participants is considered small, while phase 3 trials enroll tens of thousands of participants,” says Madhi. “Yet the startling data that our small trial generated was irrefutable, and the implications profound.”
Profile of a South African AstraZenca 足球竞彩app排名 vaccine trial participant
The majority of participants enrolled were relatively young (under 65-years-old), generally healthy, and HIV-negative. The median [middle] age of participants was 30 years old. More than half (56.5%) of the trial participants identified as male, 70.5% were Black Africans, 12.8% were white, and 14.9% identified as ‘mixed’ race.
“These demographics are important because they reflect characteristics of the overall population in South Africa. Conducting clinical trials in diverse settings like these is critical to understanding how vaccines work in local contexts,” says Madhi.
Testing a hypothesis
The primary ojective of this trial was to establish this vaccine’s efficacy against all-severity 足球竞彩app排名, irrespective of variants.
A secondary objective was to evaluate the vaccine’s efficacy against the B.1.351 variant specifically.
“When this trial began in June 2020, we were testing a vaccine against SARS-COV-2,” says Madhi. “By January 2021, SARS-CoV-2 had spawned variants, including the B.1.351 first discovered in South Africa. As a secondary objective, we tested a hypothesis: would this vaccine prove at least 60% efficacious in preventing mild to moderate 足球竞彩app排名 disease? It did not.”
The results showed that a two-dose regimen of ChAdOx1-nCov19 did not show protection against mild to moderate 足球竞彩app排名 due to the B.1.351 variant.
Crucially, Madhi notes that, “This vaccine may still help protect high-risk individuals with co-morbidities from contracting severe 足球竞彩app排名 disease, having to be hospitalised, mechanically ventilated, or dying. The AstraZeneca vaccine remains essential in the arsenal against this virus, particularly in Africa, which has already received 14 million doses of this vaccine as the 足球竞彩app排名 immunization programme starts in multiple countries.”
How the WHO took note
On 15 February 2021, the WHO recommended that the AstraZeneca vaccine still be rolled out, even in countries where the B.1.351 variant or other similar variants of concern are circulating.
A WHO news release says that the vaccine was reviewed on 8 February by the WHO Strategic Advisory Group of Experts on Immunization (SAGE), which makes recommendations for vaccines’ use in populations (i.e. recommended age groups, intervals between shots, advice for specific groups such as pregnant and lactating women). The SAGE recommended the vaccine for all age groups 18 years and above.
“While the AstraZeneca vaccine – like many other first-generation 足球竞彩app排名 vaccines – is unlikely to interrupt transmission of SARS-CoV-2 or protect against mild infection from variants like B.1.351, these first-generation vaccines could still provide the only sustainable option to prevent flooding our hospitals with severe 足球竞彩app排名 cases, and to mitigate 足球竞彩app排名 deaths once the third wave hits,” says Madhi.
Second-generation vaccine innovation
The development of an Oxford AstraZeneca and other 足球竞彩app排名 vaccines targeting the B.1351 variant is currently underway.
The South African study increased awareness worldwide of the necessity of developing vaccines that target variants specifically – and even reimagining vaccines entirely.
Innovations in vaccine technologies, platforms and designs suggest exciting advances in this field.
“The finding of our [Oxford AstraZeneca 足球竞彩app排名 vaccine] study are truly a turning point in Covid vaccine development – and a rude awakening,” says Madhi. “This one small South African study has alerted the world to the fact that second generation 足球竞彩app排名 vaccines will be required to provide protection against inevitable and persistent SARS-COV-2 variants. If we had not conducted this trial in South Africa, the world would be none the wiser.”
Wits tests the waters at Wakkerstroom
- Wits University
Wits scientists provide free testing of water quality in honour of International Water Day in Wakkerstroom.
Clean drinking water in South Africa is growing ever more scarce due to the overuse of water resources, increased frequency of drought, and problems associated with the management of water infrastructure such as water treatment plants.
In the case of the town of Wakkerstroom, the Pixley Ka Seme Municipality claims that it cannot afford to fix the mismanaged sewage system. The potential for contamination of drinking water is therefore an ongoing and growing problem for the residents of the town. The leakage of polluted water into the wetland also potentially threatens its ecological functioning, and the high plant, bird and invertebrate diversity that it supports.
In recognition of International Water Day on the Monday, 22 March 2021, Professor Mary Scholes, lecturer in the School of Animal, Plant, and Environmental Sciences, and Professor Bob Scholes, Director of the Global Change and Sustainability Research Institute, headed to Wakkerstroom for the second Water Awareness Weekend – a project jointly organised by the Wakkerstroom Natural Heritage Association (WNHA) and the University of the Witwatersrand. In order to raise awareness about the importance of water in this small, upper-catchment community, WNHA and Wits provided water quality testing at an affordable price to anyone who brought in a sample. Professors Scholes and Scholes quantified pH, total dissolved salts (TDS; mg/litre), and the presence of coliform bacteria, specifically Escherichia coli, which can indicate faecal contamination and can lead to serious diseases.
Thirty eight samples in total were tested, and the results of the water quality tests were relayed to the residents of Wakkerstroom at a general feedback session and via SMS.
Outcomes
All water samples from municipal drinking water (collected from taps) had a pH of close to 7 and a low TDS (40-60 mg/l), whereas water collected from boreholes had a slightly lower pH and a higher TDS (200-400 mg/l). All water samples collected from municipal tap water were clear and contained no coliform or E. coli bacteria.
Most of the borehole water samples showed signs of coliform bacteria contamination, and two samples contained E. coli. This contamination is almost certainly due to leaking sewage reticulation, conservancy and septic tanks and French drains, from where it percolates to the groundwater at depths of 40m.
In general, the results of the water quality tests showed that despite Wakkerstroom’s water management and infrastructural issues, the drinking water sourced from the upper catchment of the Utaga river, and purified and reticulated by the municipality through the town’s taps is of excellent quality. The use of borehole water for human consumption is not recommended until first purified.
"Making people aware of water quality and increasing demand for water in a water scarce country, is extremely important," says Professor Mary Scholes. "Water is the most important contribution of Wakkerstroom to South Africa," says Professor Bob Scholes, and is therefore an essential location at which quality water should be regularly monitored.
‘Johannesburg Lasts’, a special issue of Ellipses Journal for Creative Research
- Wits University
Online and interactive creative research from the Wits School of Arts and Arts Research Africa.
Arts Research Africa and the Wits School of Arts are proud to be launching the online and interactive Special Issue of the Ellipses [...] Journal for Creative Research titled 'Johannesburg Lasts'. Go to: http://www.ellipses.org.za
Edited by Naadira Patel, Ruth Sacks, Tara Weber, Andrei van Wyk, Karin Tan, Skye Quadling and Jarrett Erasmus, this special issue seeks to uncover, unpack and deepen investigations into present and future hauntings of Johannesburg, it’s specters, toxic legacies, its facades, and the residues of its disturbed surfaces.
{...] Ellipses Journal for Creative Research is an online peer reviewed journal started by the Wits School of Arts, managed through Arts Research Africa and supported by the Andrew Mellon Foundation. Special thanks to Editor in Chief and Digital Editor Dr Tegan Bristow with digital editors Andrea Hayes, Lara Seal, Paul Sika and Glen Mudau.
Professor Roy Shires wins International Excellence in Endocrinology Award
- Wits University
The Endocrine Society in Washington, D.C. has named Wits Professor Roy Shires as the recipient of the 2020 International Excellence in Endocrinology Award.
Shires was recognised at the virtual 2020 Laureate Awards presentation hosted by the Endocrine Society on 21 March 2021.
The annual award for international excellence in endocrinology recognises an endocrinologist who resides outside the U.S and has made exceptional contributions to the field of endocrinology in geographic areas with underdeveloped resources for endocrine research, education, clinical practice, or administration.
Endocrinology is the study of hormones. An endocrinologist is a doctor that treats diseases related to problems with hormones (chemical messengers).
Shires is Professor of Medicine in the Department of Internal Medicine, School of Clinical Medicine at Wits and in the Division of Endocrinology and Metabolism at Chris Hani Baragwanath Academic Hospital (Bara) in Soweto.
Although his interest in endocrinology is in bone and mineral metabolism, he most recently initiated a programme for transgender people at Bara to meet a growing need.
Shires joined Bara in 1986, when he was the first head of the Division of Endocrinology and Metabolism. This Wits teaching hospital is the largest in Africa and the only tertiary medical facility serving the largely impoverished and underprivileged population of Soweto.
Despite clinical demands at this under-resourced hospital, which places severe constraints on opportunities for research, Shires has managed to perform meaningful clinical research, often collaborating with basic scientists.
His scientific publications have won him the best annual publication award from the Society for Endocrinology, Metabolism and Diabetes of South Africa (SEMDSA) a number of times.
He is acknowledged as an inspiring mentor by students, postgraduates, and fellows.
Shires has often served as an examiner and examination coordinator for the endocrinology subspecialty diploma of the College of Medicine of South Africa and has also served as chairperson of the organising committee for many SEMDSA annual conferences.
In recognition of his multifaceted contributions to endocrinology in South Africa, he was acknowledged in 2013 with a lifetime award from SEMDSA “for excellence and dedication in clinical services, teaching and research in endocrinology”, and Wits awarded him its Distinguished Service Medal of Excellence.
In 2017, Shires was made an Honorary Member of SEMDSA, the only such honor bestowed in a long time.
Image of black hole shows magnetic fields around a black hole are strong enough to resist gravity
- Wits University
Wits astrophysicists are the only two scientists on African continent that contributed to the study.
The Event Horizon Telescope (EHT) collaboration, a multinational team of over 300 scientists including two astrophysicists from the University of the Witwatersrand (Wits University), has revealed today a new view of the massive object at the centre of the M87 galaxy: how it looks in polarised light.
This is the first time astronomers have been able to measure polarisation, a signature of magnetic fields, this close to the edge of a black hole. The observations are key to explaining how the M87 galaxy, located 55 million light-years away, is able to launch energetic jets from its core.
“We are now seeing the next crucial piece of evidence to understand how magnetic fields behave around black holes, and how activity in this very compact region of space can drive powerful jets that extend far beyond the galaxy,” says Monika Mo?cibrodzka, Coordinator of the EHT Polarimetry Working Group and Assistant Professor at Radboud Universiteit in the Netherlands.
“This work is a major milestone: the polarisation of light carries information that allows us to better understand the physics behind the image we saw in April 2019, which was not possible before,” explains Iván Martí-Vidal, also Coordinator of the EHT Polarimetry Working Group and GenT Distinguished Researcher at the Universitat de València, Spain. He adds that “unveiling this new polarised-light image required years of work due to the complex techniques involved in obtaining and analysing the data.”
Professor Roger Deane, SARAO/NRF Chair in Radio Astronomy at Wits and his postdoctoral researcher, Dr Iniyan Natarajan, are the only two scientists in the EHT collaboration that are based on the African continent. On 10 April 2019, the collaboration released the first ever image of a black hole, revealing a bright ring-like structure with a dark central region — the black hole’s shadow. Today’s results reveal that a significant fraction of the light around the M87 black hole is polarised.
“When unpolarised, the oscillations of the electromagnetic fields have no preferred direction. Filters such as polarised sunglasses or magnetic fields in space, preferentially let the oscillations in one direction pass through, thereby polarising the light. Thus, the polarised-light image illuminates the structure of the magnetic fields at the edge of the black hole,” says Natarajan, who was part of the EHT Polarimetry Working Group.
Black holes have long been known to launch powerful jets of energy and matter far out into space. Astronomers have relied on different physical models of how matter behaves near the black hole to better understand this process. The jet emerging from M87’s core extends at least 5000 light-years from its centre, the process behind which is still unexplained.
The observations suggest that the magnetic fields at the black hole’s edge are strong enough to push back on the hot gas and help it resist gravity’s pull. Only the gas that slips through the field can spiral inwards to the event horizon.
To observe the heart of the M87 galaxy, the collaboration linked eight telescopes around the world to create a virtual Earth-sized telescope, the EHT. The impressive resolution obtained with the EHT is equivalent to that needed to measure the size of a cricket ball on the surface of the Moon.
This setup allowed the team to directly observe the black hole shadow and the ring of light around it, with the new polarised-light image clearly showing that the ring is magnetised. The results are published today in two separate papers in The Astrophysical Journal Letters by the EHT collaboration.
“Peering as close as we can to the edge of black holes using cutting-edge techniques is precisely the sort of challenge we relish here at Wits,” says Deane, Founding Director of the newly approved Wits Centre for Astrophysics. “We are in a golden era for radio astronomy, and our involvement in projects like the Event Horizon Telescope and the Square Kilometre Array is at the centre of our plan to carry out fundamental research, and train world-class postgraduate students who will become the leading African scientists of tomorrow.”
Natarajan was involved in simulating the black hole polarisation observations and was also part of the efforts to calibrate and generate the polarised image. Deane and Natarajan have also written one of the software packages that is being used to simulate black hole observations within the EHT collaboration.
"Our collaboration developed new techniques for analysing the polarisation data, which were validated on simulations before being applied to real observations,” says Natarajan.
“Such challenging projects provide the opportunity to develop techniques which later find wider applicability in the community in ways which can pleasantly surprise us."
Wits announces team to advance AI research in Africa
- Wits University
The team, led by Professor Zeblon Vilakazi, will lead Africa’s effort to advance artificial intelligence research and its application across the continent.
Wits University has announced its team that will advance Africa’s AI initiative, Cirrus, a private sector led initiative bringing together academia and industry for the establishment of a world class artificial intelligence (AI) research and application capability for Africa.
The university team will be led by Professor Zeblon Vilakazi, Vice-Chancellor and Principal, with Professor Emeritus Barry Dwolatzky (project lead), Professor Nithaya Chetty, Dean of the Faculty of Science, as the champion for scientific engagement, and Dr Roy Forbes as the engagement coordinator.
The university team (Biographies) will work closely with the Cirrus team (Biographies) that was announced at AI Expo Africa in 2020.
Priorities and challenges
The university team is focused on two key priorities:
Academic: Supporting the establishment of the AI Africa (AIA) Consortium which provides the mechanism for bringing together academic and research institutions with a vested interested in the success and sustainability of Cirrus as Africa’s artificial intelligence effort.
Government: Lead engagement and coordination with government on:
the adoption of Cirrus and;
support for local academic and research institutions to invigorate AI research and to further the application of AI across various academic and industrial domains.
Cirrus is the largest and most complex undertaking of its kind in Africa’s history; however, the major challenges are neither financial nor technological. Rather, it is rallying the academic and research institutions in Africa for there to be a critical mass of research and applications that can fully leverage the capabilities that will be established with Cirrus. Most of the institutions participating in the AIA Consortium will be publicly funded academic institutions from across the continent.
With Wits University, Cirrus now has a leading university on the continent and a competent team to spearhead this important work.
South African and numerous other African universities currently host various academic and industrial research groups. These groups are involved in, amongst other things, activities ranging from environmental and climate change research, medical research to materials research and energy storage development and design.
“Most if not all these existing research thrusts could benefit significantly from incorporating AI methodologies in their research activities. Furthermore, in working together as opposed to working in isolated groups the impact of the research will also be improved,” says Gregg Barrett, Founder of Cirrus.
The establishment of Cirrus is therefore a rallying call to the academic and research institutions in Africa for there to be a critical mass of research and applications that can fully leverage the capabilities that will be established with Cirrus.
“We at Wits have been on a long journey with Cirrus to bring all of the elements of this ambitious partnership into place. We are hoping to soon begin to sign up members of the AI Africa (AIA) Consortium and to see tangible benefits flowing from our engagement with Cirrus,” says Dwolatzky.
Wits University’s endeavours extend beyond the AIA Consortium and includes catalysing necessary strategic policy engagements with government to ensure impact on important research and societal objectives.
“The critical strategic steps that need to be taken in Africa have long been spoken about and now is the time for action. AsMarc Andreessenrecently pointed out, a takeaway from the COVID-19 pandemic is that people need to think about their occupation and contribution to society. If you are not helping people directly, and your occupation does not lead to something being built and contributes little to society, you are failing yourself. Cirrus represents Africa’s collective opportunity to move past the talk and get building on solving real problems with significant societal impacts,” says Barrett.
Wits students develop unique cannabis cultivation tech
- Wits University
Two master’s students are developing new technologies aimed at disrupting the booming cannabis, or so called ‘green gold’, industry.
Their novel cannabis cultivation technologies, uniquely developed for the African climate, have earned Constant Beckerling and Anlo van Wyk special recognition in the Biosciences category of the Gauteng Accelerator Programme (GAP) – an annual competition held by the Innovation Hub, a subsidiary of the Gauteng Development Agency. The competition is aimed at tech entrepreneurs who develop technologies that can benefit the Gauteng, South African and African economies.
Even though they are both passionate cannabis growers, their focus is on developing agri-tech for the sector. To do this they have created a startup called AgriSmart Engineering (Pty) Ltd during 足球竞彩app排名 lockdown last year. With a focus on closed-loop hydroponics and aquaponics, the AgriSmart team specialises in the design and implementation of automated smart growing systems.
Growing for gold
Beckerling and Van Wyk are approaching their speciality of cannabis cultivation as an engineering problem and marrying their growers experience and intuition with their engineering and technical backgrounds.
“There is a matrix of factors for cannabis cultivation that we consider. As an engineering startup we are developing cultivation technologies for the African climate. For cannabis cultivation, South Africa faces shortcomings such as water stress and irregular electricity supply at a high cost. But the country also has strengths such as superior solar radiation and being one of the first countries that are in the process of commercialising cannabis,” Beckerling says.
To strike ‘green gold’ early, Beckerling and Van Wyk, both doing their MSc in Electrical Engineering, entered a blueprint for a cannabis cultivation research facility they designed in the GAP competition. Their entry also included two main agro-processing offerings:
cannabis specific LED grow lights in an automated Internet of Things (IoT) environment, customised for the research facility to accommodate the photobiology of the cannabis plants;
and proprietary organic hydroponic nutrient, which they formulate based on the respective hormonal growth cycles of the plants.
“Our novel LED lighting is a technology which is set to disrupt the cannabis industry. This technology is brought about by combining one of South Africa’s unique strengths, which is solar radiation, with engineering disciplines like artificial intelligence, electronic and mechanical engineering,” says van Wyk.
The industry standard is currently to use High Intensity Discharge Lighting (HID) lighting.
“Our LED lighting tech runs 2.5 times more efficient on electricity than High Pressure Sodium (HPS) lights and even more so compared to Metal Halide (MH) fixtures. The lifetime of our LED fixtures is also significantly longer than that of HID – about 15 times at the upper-end. This translates to about 80 000 hours of light compared to about 5 000 hours lifetime for the HID – leading to significantly lower maintenance costs.” explains Beckerling.
According to Van Wyk the LED lighting fixtures are also dimmable. “So we could implement an artificial intelligence algorithm that takes in environmental input and based on those inputs it controls what the lighting output should be in that specific moment. This leads to optimisation of power consumption which brings down electricity costs.”
For the competition they had to do financial projections around their fixtures and the potential benefits of their disruptive tech. The bottom line is that over 5 years the cultivator stands to save R 25 million per hectare in electricity costs just on the lighting alone, compared to industry standard HID fixtures.
The two engineers are also formulating their own organic hydroponic nutrients for cannabis. “Besides electricity, your biggest running cost in your facility is going to be your nutrient cost which increases with scale. It’s therefor crucial to get the right nutrients that tailor to your plants’ specific hormonal growth phases,” says Beckerling.
Cannabis plants require different nutrients in different stages of their development and require these nutrients in different concentrations as they mature. “We are doing a cannabis-specific hydroponic nutrient that we formulate completely organically, and we are planning to register it as a type 2 organic fertilizer in line with the regulations of South African law,” Beckerling explains.
The research and development of this nutrient takes time and money. Securing funding to develop and commercialise this nutrient, while producing it at more than 10 times cheaper than the current direct market competition, is one of their biggest stumbling blocks.
Into the near future
Their next aim is to build a demonstration facility to show how their technologies are working on the ground. “The current growing technology is very archaic, so if one party does decide to use this new tech, it will force the rest of the industry to follow suite if they want to compete on price,” Van Wyk says.
Beckerling adds: “We believe the market will settle at who can produce the most consistently at the cheapest price and at the highest quality.”
The research facility will also provide an immense scope of research, particularly in engineering (chemical, electrical, mechanical and civil); computer science (machine learning, AI, big data, bio-informatics, robotics, software development and others); plant and biological sciences; physical sciences; and pharmacology, psychology and medicine. They estimate that many companies can spawn from this facility through the commercialisation of new technologies.
Biopark, a division of The Innovation Hub, recently offered AgriSmart a contract to help incubate the startup, which they accepted.
Disentangling the neuromolecular networks involved in speech and language
- GCRF START
As a biochemist/biophysicist working primarily with proteins, Sylvia Fanucchi is naturally drawn to the mechanisms of interactions of biological macromolecules.
She is a senior Lecturer in the Protein Structure Function Research Unit (PSFRU) at the University of the Witwatersrand (Wits) in South Africa, and interested in how things work at the molecular and atomic level, and how the structure of macromolecules leads to their function.
This has inspired her research for the past six years which involves disentangling the neuromolecular networks involved in speech and language.
“With the GCRF START grant, the doors to collecting the detailed structural information we need through studying and obtaining crystal structures, have been opened for groups in Africa like ours. I have had multiple opportunities, thanks to the grant, to send crystals to the UK’s world class national synchrotron, Diamond Light Source (Diamond),” writes Fanucchi.
The Global Challenges Research Fund (GCRF) and START (Synchrotron Techniques for African Research and Technology) grant is a collaborative project between scientists in Africa and the UK working together on research using synchrotron science.
AI-powered Algorithm released to detect the third wave in South Africa
- Wits University
While models show a low risk of a third wave in South Africa, the country is still highly vulnerable.
An Artificial Intelligence (AI)-based algorithm that has been designed by the University of the Witwatersrand (Wits University) in partnership with iThemba LABS, the Provincial Government of Gauteng and York University in Canada, shows that there is a low risk of a third infection wave of the COVID pandemic in all provinces of South Africa.
The AI-powered early detection system functions by predicting future daily confirmed cases, based on historical data from South Africa’s past infection history, that includes features such as mobility indices, stringency indices and epidemiological parameters.
“These parameters are consistent with clinical public health measures that can contain, control and mitigate against the COVID-19 pandemic,” says Dr. James Orbinski, Director of the York University Dahdaleh Institute for Global Health Research.
The AI-based algorithm works in parallel, and supports the data of an already existing algorithm that is based on more classical analytics. Both of these algorithms work independently and are updated on a daily basis. The existence of two independent algorithms adds robustness to the predictive capacity of the algorithms. The data of the AI-based analysis is published on a website that is updated on a daily basis.
“The current data shows us the risk for a third infection wave of COVID-19 is small across most of provinces in South Africa, but we still remain highly vulnerable,” says Professor Bruce Mellado, Director of the Institute for Collider Particle Physics at Wits University.
It is crucial that South Africans continue to adhere to the South African government’s COVID regulations and take all necessary precautions to prevent the spread of the pandemic.
The advent of infection waves is driven by circumstances that are difficult to predict and therefore to control. In this complex environment, early detection algorithms can provide an early warning to policy makers and the population. Early detection algorithms are able to issue an alert when the data displays a significant change that is consistent with the advent of a new wave.
While algorithm-based predictions can never be 100% accurate, Mellado is confident that the model presents a very good prediction over at least a two-week period. While predictions can be made over longer-term periods, these predictions become less accurate.
The model is trained on the interim period in between waves one and two in all of the South African provinces. The algorithm was tested with data taken during the period of past peaks to evaluate its performance.
“AI technology provides us with invaluable potential to develop early detection and alert systems that are highly needed for rapid and dynamic decision making under risk and uncertainty under the current pandemic,” says Ali Asgary, Professor of Disaster & Emergency Management and Associate director of York University's Advanced Disaster, Emergency, and Rapid-response Simulation (www.adersim.info.yorku.ca)
AI is very effective in navigating through complex problems with a large number of parameters and dimensions, while at the same time learning from the data. Data hides within itself a wealth of information that AI can extract efficiently.
“Our team’s development of an early detection algorithm for the third wave speaks to the power of AI to generate data-based solutions to highly complex problems,” says Professor Mellado, Director of the Institute for Collider Particle Physics.
The project is supported by the Canadian International DevelopmentResearch Centre (IDRC) through the Africa-Canada Artificial Intelligence and Data Innovation Consortium.
However, while it was previously thought that this beast of a creature – that grew to about the size of an adult hippo or rhino, and featuring a thick crocodilian tail – was too heavy and sluggish to be an effective hunter, a new study has shown that the Anteosaurus would have been able to outrun, track down and kill its prey effectively.
The team found that the organ of balance in Anteosaurus (its inner ear) was relatively larger than that of its closest relatives and other contemporaneous predators. This indicates that Anteosaurus was capable of moving much faster than its prey and competitors. They also found that the part of the brain responsible for coordinating the movements of the eyes with the head was exceptionally large, which would have been a crucial trait to ensure the animal’s tracking abilities.
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