Researchers at Monash University supported by a Discovery Projects grant have provided a fundamental advance regarding how T cells become activated when encountering pathogens such as viruses.
The study was co-led by ARC Future Fellow Professor Nicole La Gruta, Australian Laureate Fellow Professor Jamie Rossjohn and former Future Fellow Professor Stephanie Gras, with first author Dr Pirooz Zareie from the Monash Biomedicine Discovery Institute.
The researchers have found that T Cells, which play a crucial role in the body's immune system, need to recognise pathogens such as viruses in a particular orientation in order to become activated to fight the intruder.
This activation occurs when special T cell receptors (TCR) on the surface of the T cell recognise and bind to the virus fragments (antigens) on infected cells. After recognising the antigen, the T cell activates and is able to kill the infected cell.
'The central issue is that there are millions of different T cell receptors (TCRs) in the human body, and a vast array of viruses, making it difficult to understand the rules around how T cell receptor recognition of a virus drives T cell activation. Indeed, it is a problem that has remained contentious for over 25 years,' says Professor La Gruta.
'Our study has shown that the orientation in which the T cell receptor binds is a primary factor determining whether the T cell receives an activating signal.'
'This is an advance in our fundamental understanding of how a T cell needs to ‘see’ pathogenic antigens in order to be activated,' she said. 'It has clarified a critical mechanism essential for effective T cell immunity. It is also relevant to the ongoing development of immunotherapies that aim to boost the activation of T cells.'
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TCR-pMHC recognition – through the looking glass. The image shows a brightly coloured canonical interaction between TCR and pMHC which is conducive to signal transduction. The faded mirror image shows a reversed TCR-pMHC interaction which is unable to support signal transduction and thus T cell activation. Image created by Dr. Erica Tandori (Rossjohn lab)
The first detailed cross-section of a galaxy broadly similar to the Milky Way, published by researchers at ASTRO 3D, reveals that our galaxy evolved gradually, instead of being the result of a violent mash-up. The finding throws the origin story of our home into doubt.
The galaxy UGC 10738 turns out to have distinct ‘thick’ and ‘thin’ discs, similar to those of the Milky Way. This suggests, contrary to previous theories, that such structures are not the result of a rare long-ago collision with a smaller galaxy. They appear to be the product of more peaceful change.
The finding was made by a team led by two Discovery Early Career Researcher Award (DECRA) recipients, Nicholas Scott and Jesse van de Sande, from ASTRO 3D and The University of Sydney.
'Our observations indicate that the Milky Way’s thin and thick discs didn’t come about because of a gigantic mash-up, but a sort-of ‘default’ path of galaxy formation and evolution,' says Dr Scott.
'From these results, we think galaxies with the Milky Way’s particular structures and properties could be described as the ‘normal’ ones.'
Dr Scott also says that UGC 10738’s edge-on orientation meant it was simple to see which type of stars were in each disc.
'It’s a bit like telling apart short people from tall people,' he says. If you try to do it from overhead, it’s impossible, but it if you look from the side, it’s relatively easy.
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The UGC 10738 galaxy is very similar to our own. Credit: Centre de Données astronomiques de Strasbourg / SIMBAD / PanSTARRS.
Sea levels were much lower at the time of their arrival, meaning that Australia was connected to New Guinea and Tasmania in a land known as Sahul, that was 30% bigger than Australia is today. Evidence is scarce as there are only a few archaeological sites that date to such early times.
It is assumed that early Australians navigated in new territories by focusing on prominent land features protruding above the relative flatness of the Australian continent. The researchers then used four pieces of information to build a computer model of paths travelled: (1) topography; (2) the visibility of tall landscape features; (3) the presence of freshwater; and (4) demographics of the travellers. To map these features, they built the most complete digital elevation model for Sahul ever constructed, including areas now underwater.
The pathways chosen by the computer model were then compared with the distribution of the oldest known archaeological sites in Sahul, which provided a weighting of probabilities for each path, providing a scale going from the 'most likely' to the 'least likely' chosen paths. This generated a map of most likely pathways, what the group dubbed the 'super-highways' of Indigenous movement. The next most likely paths are marked by dotted lines.
The researchers note that the paths shown on the map echo well-documented Aboriginal trade routes criss-crossing the country. There are also striking similarities between the 'super-highways' and the most common trading and stock routes used by early Europeans, who followed already well-known routes established by Aboriginal peoples.
Australian Laureate Fellow Professor Lynette Russell notes that the new modelling establishes the infrastructure for detailed local and regional studies to engage respectfully with Indigenous knowledges, ethnographies, historical records, oral histories, and archives.
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How the Sahul landmass would have looked more than 50,000 years ago. Credit: CABAH.
An ARC Discovery Project led by Dr Joe Blythe from Macquarie University is investigating the similarities and differences in Aboriginal conversation and non-Aboriginal conversation. The 'CIARA' project – standing for 'Conversational Interaction in Aboriginal and Remote Australia' – is the first large-scale exploration of conversational style in Australia.
The project is investigating everyday conversation, comparing social interaction across different languages, cultures and geographic locations. Using modern Conversation Analytic/Interactional Linguistic techniques, the research team aims to re-examine claims that Aboriginal Australians conduct conversations in different ways to Anglo-Australians. A field trip conducted by Dr Joe Blythe in Halls Creek and Ringer Soak has already recorded and transcribed multiparty conversation in the Jaru language, while partner investigator Professor Lesley Stirling from The University of Melbourne is collecting multiparty conversations in Kimberley varieties of Australian English, as spoken by gardiyas (non-Aboriginal people) in Kununurra and Halls Creek.
The research is collecting the evidence to explicate Aboriginal and non-Aboriginal conversational norms, pinpointing differences which may lead to intercultural miscommunication. Such differences in expectations surrounding interactional norms have led to disadvantage for certain Aboriginal people within legal, educational and medical settings. The research team will disseminate the findings to service providers within these sectors, to Aboriginal communities and to Aboriginal organisations, in the hope of improving the quality of intercultural engagement.
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A conversation being recorded for the project. From left to right: Bonnie Nyaburru Seela, Nida Nangari Tchooga and Clara Nanagu Yundi. Credit: Josh Dahmen.
An international research team, including researchers from the ARC Centre of Excellence for Australian Biodiversity and Heritage (CABAH) at the University of Wollongong (UOW), has determined that the arrival of ancient humans to uninhabited islands doesn’t always lead to widespread extinctions as is often thought.
The research team was led by ARC Future Fellow Associate Professor Julien Louys, from the Australian Research Centre for Human Evolution at Griffith University. By examining archaeological and paleontological records of all islands inhabited by humans over the last 2.6 million years, the team found that humans weren’t always destructive agents, and their arrival often had minimal impacts on biodiversity loss.
'We often have this picture that as soon as people arrive in a new ecosystem, they cause untold amounts of damage, but we found that this was only the case for the most recent human arrivals on islands,' says Associate Professor Louys.
'Based on classic cases of island extinction from the more recent past, we expected that mass extinction should shortly follow island colonisation, however, when we examined the data, there were very few cases where this could be demonstrated.'
'Even in cases where there was a close link between human arrival and island extinctions, these could not be disentangled from records of environmental change brought about by global climatic events and changing sea levels.'
The team also recorded several examples of human ancestor extinctions and instances where humans had to abandon islands.
'The unique ecological conditions that drive island extinctions definitely didn’t spare humans either,' said Australian Laureate Fellow, Professor Sue O’Connor of The Australian National University, the senior researcher on the study.
ARC-supported researchers from The University of Adelaide and Osaka University (Japan), have worked together to produce a new 'multiplexer' chip made from pure silicon, which promises to be the key to unlocking the next generation of wireless communications: 6G and beyond.
Associate Professor Withawat Withayachumnankul from The University of Adelaide’s School of Electrical and Electronic Engineering says that compact and practical multiplexers have not been developed for the terahertz range, a region of the electromagnetic spectrum that has a far broader bandwidth than that of conventional wireless communications. The new terahertz multiplexers, which are economical to manufacture, will be extremely useful for upcoming ultra-broadband wireless communications.
'In order to control the great spectral bandwidth of terahertz waves, a multiplexer – which is used to split and join signals – is critical for dividing the information into manageable chunks that can be more easily processed and so can be transmitted faster from one device to another,' says Associate Professor Withayachumnankul.
'The shape of the chips we have developed is the key to combining and splitting channels so that more data can be processed more rapidly. Simplicity is its beauty.'
Experimentation with the multiplexer, showing connection to external systems. The multiplexer does not have any form of supporting substrate. Credit: Dr Daniel Headland, Osaka University.
Some of the earliest and most important shipwrecks in Western Australia’s history are the subject of a new book, Shipwrecks of the Roaring 40s, the outcome of an international collaboration supported by an ARC Linkage Project. The book is edited by The University of Western Australia’s (UWA), Professor Alistair Paterson, and UWA Honorary Doctorate recipient, Jeremy Green, and reveals new information about shipwreck sites that were first excavated in the 1970s and 1980s.
Professor Paterson, who leads a team of researchers at the WA Museum with Mr Green, said the work was conducted in various settings including museums, computer laboratories, archives and from fieldwork at selected sites on the coast and offshore islands of WA.
'The Batavia was wrecked on Morning Reef in the Abrolhos Islands off the coast of WA in 1629 with 300 people on board,' Professor Paterson says. 'It is one of WA’s most significant shipwrecks because of the extraordinary story of its mutiny and the story of the Dutch East India Company in the Indian Ocean.'
'Five expeditions to Beacon Island and other locations related to the Batavia shipwreck saw the discovery and excavation of the graves of 12 victims from the wreck.'
'The program of forensic work at UWA and in Europe to uncover the burials from Beacon Island is outlined in the book and provides new knowledge of the oldest European human remains in Australia.'
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Survivors of the Batavia shipwreck racing to the rescue ship. Source: Wikipedia.
New ARC-supported research has confirmed that Einstein’s theory of gravity accurately describes current observations of black holes, from the smallest to the largest.
General relativity, Einstein’s theory of gravity, is best tested at its most extreme – close to the event horizon of a black hole. This regime is accessible through observations of the shadows of supermassive black holes which reside at the centre of galaxies, and gravitational waves, which are ripples in the fabric of our Universe from colliding stellar-mass black holes.
The theory provides a specific description of a black hole’s effect on the fabric of space-time: a four-dimensional mesh which describes how objects move through space and time. Known as the Kerr metric, this prediction can be related to the bending of light around a black hole, or the orbital motion of binary black holes.
For the first time, scientists from the ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav), the Event Horizon Telescope (EHT) and the LIGO Scientific Collaboration, have outlined a consistent approach to exploring deviations from Einstein’s general theory of relativity in these two different observations.
In 2019, the EHT generated silhouette images of the black hole at the centre of the galaxy M87, with a mass several billion times that of our Sun. Meanwhile, the LIGO and Virgo gravitational-wave observatories have been detecting gravitational waves from merging stellar mass black holes since 2015. By combining the measurements of the shadow of the supermassive black hole in M87 and gravitational waves from a couple of binary black hole detections, called GW170608 and GW190924, the researchers were able to test Einstein's theory – and they found no evidence for deviations from what it predicted.
'Different sizes of black holes may help break the complementary behaviour seen here between EHT and LIGO/Virgo observations,' says Ethan Payne, co-author of the study and research assistant at OzGrav. 'This study lays the groundwork for future measurements of deviations from the Kerr metric.'
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Artist's impression of binary black holes about to collide. Credit: Mark Myers, OzGrav-Swinburne University.
An outcome of an ARC Linkage Project, a Swinburne-produced documentary exploring our obsession with superheroes, has been awarded Best Documentary Short at the 2020 international FantaSci Awards.
Produced by Swinburne’s Associate Professor Liam Burke and co-produced by Mark Hellinger, the short documentary is an examination of the many ways that superheroes inspire us, with contributions from superhero stars, comic creators, and fans.
'From blockbuster films to convention cosplay, superheroes have never been more popular or pervasive,' says Associate Professor Burke.
'This project was developed over several years, and draws on over one hundred interviews with TV stars, comic book creators, and costume-clad fans. While often dismissed as escapist fantasy, this film demonstrates how these high-flying heroes can bring people together and provide hope in difficult times.'
'It provides an affectionate portrait of the many ways that superheroes inspire us – from a marriage proposal at a comic book convention, to heralding the arrival of an Indigenous Australian Superhero.'
The documentary is just one of the outcomes of the ARC Linkage Project Superheroes and Me, in which Swinburne investigators Professor Angela Ndalianis and Associate Professor Burke collaborated with the Australian Centre for the Moving Image (ACMI), Australia’s national museum of film, TV, videogames, digital culture and art.
The ARC Centre of Excellence for Quantum Computation and Communication Technology (CQC²T), led by Scientia Professor and ARC Laureate Fellow, Michelle Simmons, at The University of New South Wales (UNSW) is committed to attracting, retaining and developing women in STEM. The team is looking for female PhD and Honours students to join their multidisciplinary research group of scientists and engineers developing quantum computing and communication technologies of the future.
Throughout 2021, top-up scholarships are available to female candidates that have secured a new PhD or Honours role at one of CQC²T's Australian partner universities.
Successful candidates are supported by a mentor at their chosen university, and given access to a wide range of resources to assist with the development of a career in quantum computing, as well as top up funding of up to $5000 per annum for up to 3 years.
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