ScienceAlert - Latest Stories

Platypus needs large gene pool

Sun, 20 May 2012 15:22:41 GMT

While platypuses on the Australian mainland and in Tasmania are doing well, those on small islands are at risk of being wiped out by disease.

Image: JohnCarnemolla/iStockphoto

Platypuses on the Australian mainland and in Tasmania are fighting fit but those on small islands are at high risk of being wiped out from disease, according to a University of Sydney study.

The finding has important implications, not only for the management of the platypus but for other populations with limited genetic variation, including the iconic koala.

"We have identified platypus populations which are at high risk of disease epidemics due to low genetic diversity," said Mette Lillie, a PhD researcher at the University of Sydney's Faculty of Veterinary Science.

Lillie is the lead author of the study on platypus populations published this month in the Journal of Heredity Advance Access. Lillie's supervisor Kathy Belov, Associate Professor in Animal Genetics is the study's senior author.

The platypus has a wide distribution in Australia, including island populations on Tasmania, King Island and Kangaroo Island.

King Island is located north-west of the main island of Tasmania and Kangaroo Island is south-west of Adelaide.

"Our study measured how immunologically fit platypus populations are based on how much variation there is in their immune genes. Variation is very important for populations because the more variation there is, the more pathogens the populations can resist," Lillie said.

The study found platypus colonies on the mainland and in Tasmania show high immune gene diversity. The smaller island platypus populations were a different story. The Kangaroo Island population had very low diversity and the King Island population had no immune gene diversity at all.

The lack of diversity in the Kangaroo Island population can be explained by the fact that only a small number of platypuses were introduced there during the 1930s and 40s, which would have limited genetic diversity.

The King Island population has been isolated from Tasmania and the mainland since the last ice age, 14,000 years ago, and genetic diversity would have been lost in this small population due to inbreeding and random genetic drift an important evolutionary force that influences genetic diversity from one generation to the next. Genetic drift is especially significant in small isolated populations where it tends to decay genetic diversity over time.

The team has previously shown that low immune gene diversity allowed a contagious cancer to decimate Tasmanian devils. Identification of a shallow gene pool in Kangaroo and King Island platypuses raises concerns about their long term survival.

These populations will need to be carefully managed and monitored for signs of disease outbreaks, as an introduced disease could reach epidemic proportions.

This research has important implications for conservation management as it reinforces the idea that healthy populations need high levels of immune gene diversity. Large populations of immunological clones are a recipe for disaster, and time bombs for disease epidemics.

Editor's Note: Original news release can be found here.

Next-gen cancer drugs on the way

Sun, 20 May 2012 15:18:24 GMT

The new drugs work by binding the iron in tumour cells, preventing them from growing, while leaving other cells alone.

Image: Eraxion/iStockphoto

A new class of anti-cancer drugs which control the growth and spread of cancers and do so with minimal side effects is being developed by researchers at the University of Sydney.

"These new agents attack a fundamental characteristic of cancer cells while leaving normal cells alone," said Professor Des Richardson, from the Bosch Institute in Sydney Medical School.

"They work by binding the iron in tumour cells, preventing them from growing. We believe they have the potential to be an effective new strategy, to be 'next generation' drugs, for a range of cancers including highly aggressive pancreatic cancer.

Because they do not act on non-cancerous cells these new agents dramatically reduce a range of distressing side effects familiar to people undergoing cancer treatments such as chemotherapy and radiotherapy.

Professor Richardson is the head of the Iron Metabolism and Chelation Program at the University and has been conducting research in this area since the early 1990s.

The latest research on the chelators is led by post-doctoral researcher and NHMRC Early Career Fellow, Dr Zaklina Kovacevic.

In the Journal of Biological Chemistry, the researchers outline how these new agents increase the levels of a molecule (NDRG1) which inhibits the spread of cancer, including prostate and colon cancers.

"Together with a recent article in the journal, Antioxidants and Redox Signaling, these studies advance our knowledge of cancer cell biology and how we can target specific molecules to stop cancer progressing," Dr Kovacevic said.

Professor Richardson is currently in advanced discussions on a licensing deal with an American company for developing the compound to the stage of clinical trials.

"This will present a significant step forward in the fight against cancer and provide cancer sufferers new hope for a better outcome," Professor Richardson said.

"It is a difficult step to go from the often quoted bench to bedside, but it has been greatly helped by the Bosch Institute's Translational Grants program, and by an NHMRC Development Grant."

The Executive Director of the Bosch Institute, Professor Jonathan Stone stated: "For anyone who has been through, or cared for a cancer sufferer through, the purgatory of chemotherapy, the prospect of anti-cancer drugs which are broadly effective but with few side effects is immensely welcome."

Editor's Note: Original news release can be found here.

Older mums face health risks

Sun, 20 May 2012 15:12:41 GMT

More women are choosing to have children later in life, however they may be putting their health at risk in doing so, the study suggests.

Image: kycstudio/iStockphoto

Delayed childbearing for an increasing number of women is putting them at higher risk of serious illness and complications, a new study has found.

A study of women in the Australian state of Victoria, published in The Australian and New Zealand Journal of Obstetrics and Gynaecology also observed complications associated with older women giving birth placed greater demand on health care services.

Led by Dr Mary Anne Biro, School of Nursing and Midwifery, Monash University, researchers examined the link between older maternal age, of women 35 years and older, and selected morbidities and complications, using data on all births over 20 weeks’ gestation for 2005-06 from the Victorian Perinatal Data Collection.

Older childbearing women were found to be at higher risk of gestational diabetes, placenta praevia, pre-eclampsia, perineal injury, haemorrhage, caesarean deliveries and multiple births.

As proportions of older women giving birth increase, Dr Biro said child bearing at the age of 35 years and older continues to be associated with poorer outcomes and some complications are twice as likely.

“The study was the first to examine and report on the age-risk association for a range of obstetric morbidities for women giving birth in Victoria,” Dr Biro said.

“The ideal age to have a baby is earlier than your late 30s, and we do want women and their doctors to know the risks.

“The findings have implications for childbearing women, maternity clinicians and health services.”

Impacts attributed to complicated deliveries included disruption to families, medical costs, rates of hospitalisation and surgery.

It comes as the proportion of older women giving birth increased from 7.5 per cent in 1985 to 26.4 per cent in 2008.

In Victoria during 2005-06, 133, 359 women gave birth, of whom 24 per cent were aged 35 years or older.

Editor's Note: Original news release can be found here.

Drug shrinks brain tumours

Sun, 20 May 2012 15:06:08 GMT

Most patients whose melanoma has spread to the brain die within four months. But the trial's results showed brain tumours in nine of the 10 patients shrank within the first six weeks. All 10 patients survived beyond five months.

Image: amphotora/iStockphoto

Australian researchers have reported promising results with a new drug that shrinks brain tumours in melanoma patients. Their findings are published in The Lancet medical journal.

Medical researchers at the University of Sydney, Melanoma Institute Australia, Sydney's Westmead Hospital and Westmead Millennium Institute, say a new drug they have been testing to treat deadly melanoma in the body also shows, for the first time, an ability to shrink secondary tumours (metastases) in the brains of patients with advanced forms of the disease.

They say the new drug may add months to the lives of patients whose melanoma has spread to the brain. Most patients with brain metastases die within four months. The trial's results, however, showed brain tumours in nine of the 10 patients shrank within the first six weeks. All 10 patients survived beyond five months, two patients survived beyond 12 months. One patient was alive at 19 months.

The drug called Dabrafenib works by targeting a gene mutation found in melanoma cancer, called the BRAF mutation, which is present in 50 percent of human melanomas. The drug works by binding to the activated mutant form of the BRAF protein in the melanoma cell, causing the cell to stop proliferating. In many cases it shrinks and disappears.

The lead author of the study, Dr Georgina Long, from the University of Sydney, Melanoma Institute Australia and Westmead Hospital said, "This is the first evidence that we have a systemic drug therapy that helps prolong survival in patients with multiple melanoma brain metastases. The findings are among the most important in the history of drug treatment for melanoma.

"Currently there is no effective systemic treatment for melanoma brain metastases, and patients whose cancer has spread to the brain are frequently excluded from promising clinical trials. Until now, there has not been a single drug that has shrunk brain metastases in more than 10 out of 100 patients with metastatic melanoma. This drug had a 90 percent success rate in reducing the size of brain metastases.

"Brain metastases in melanoma are a major unsolved problem. Up to this point, melanoma has been notoriously resistant to drug therapy in general, and responses in highly lethal brain metastases are particularly uncommon. Providing these early data are supported in larger cohorts of patients and durable responses are confirmed, this activity in the brain may assist in addressing a large unmet need in patients with metastatic melanoma worldwide," Dr Long said.

Editor's Note: Original news release can be found here.

Millenium of data proves warming

Thu, 17 May 2012 15:33:08 GMT

“Our study revealed that recent warming in a 1,000-year context is highly unusual and cannot be explained by natural factors alone, suggesting a strong influence of human-caused climate change in the Australasian region."

Image: Marcco73/iStockphoto

In the first study of its kind in Australasia, scientists used 27 natural climate records to create the first large-scale temperature reconstruction for the region over the past 1,000 years.

The study led by researchers at the University of Melbourne, used a range of natural indicators including tree rings, corals and ice cores to study Australasian temperatures over the past millennium. They then compared these with climate model simulations.

Dr Stephen Phipps, a researcher with UNSW’s Climate Change Research Centre and the Centre of Excellence for Climate System Science led the climate model simulation research. He said the results showed there were no other warm periods in the past 1,000 years that match the warming experienced in Australasia since 1950.

“Our study revealed that recent warming in a 1,000-year context is highly unusual and cannot be explained by natural factors alone, suggesting a strong influence of human-caused climate change in the Australasian region,” Dr Phipps said.

The study published in the Journal of Climate will form the Australasian region’s contribution to the 5th IPCC climate change assessment report chapter on past climate.

Lead researcher, Dr Joelle Gergis from the University of Melbourne said using ‘palaeoclimate’ or natural records, such as tree rings, corals and ice cores, are fundamental in evaluating regional and global climate variability over centuries before direct temperature records started in 1910.

Dr Gergis collated these natural records provided by decades of work by more than 30 researchers from Australia, New Zealand and around the world.

The reconstruction was developed using 27 natural climate records calculated in 3,000 different ways to ensure that the results were robust.

She said reconstructions of regional temperature not only provide a climate picture of the past but also a significant platform to reduce uncertainties associated with future climate variability.

The study is part of a global collaboration, PAGES, Past Global Changes Regional 2K initiative, which is working to reconstruct the past 2,000 years of climate across every region in the world in order to reduce uncertainties associated with future climate change projections.

Collaborators include the Climate Change Research Centre and the ARC Centre of Excellence for Climate System Science, University of New South Wales where the climate modelling was conducted.

Editor's Note: Original news release can be found here.

Crabs fake it to avoid fights

Thu, 17 May 2012 15:25:21 GMT

Crabs who live in low-competition areas have large but weak claws to discourage others from fighting with them, the research suggests.

Image: KevinDyer/iStockphoto

Crabs will fake it to avoid a fight, research has found.

Dr Robbie Wilson, Head of the Performance Lab at UQ, where this study was conducted, said the research identified more than just some crabby behaviour.

“This study is important because it reveals the general principles behind how liars and cheats are controlled and encouraged in nature.

“Whether it's a soccer player diving to fool a referee or a crab trying to intimidate a rival with weak claws, our lab has shown that individuals cheat more when their deception is likely to go undetected,” Dr Wilson said.

Ms Candice Bywater who is finishing her PhD on fiddler crabs, said that she found that more males bluff their way through fights when they are less likely to get caught.

“When there are lots of crabs living in one area, there is lots of competition for resources like females and food. High competition means there is a greater chance of males having to fight each other to win resources compared to when there are not many crabs about. Those crabs might not have to fight at all,” Ms Bywater said.

“Crabs that have strong claws will generally win fights. Producing large and strong claws is important to their survival.

“Where crabs are likely to have to fight a lot, the crabs are producing large, strong, reliable claws. We found that when there are not many other male crabs in a population (low competition), males produce large but relatively weak claws (unreliable), as they don't have to fight as often and ultimately because they can get away with it."

In nature, signals may be behavioural, as in growling or posturing, but are often structural, including the antlers of a deer, and the enlarged fore-claw of many crustaceans.

A male that overstates his quality could improve his ability to gain food or mates, but surprisingly, most signals are honest reflections of a male's prowess.

Editor's Note: Original news release can be found here.

Killer dinosaurs found in Aus

Thu, 17 May 2012 15:12:02 GMT

The species ranged from the cat-sized killers (claw and vertebra shown on the right) and a nine-metre-long T. Rex-like predator (claw on left).

Image: Benson et al

At least seven different killer dinosaurs once lived in what is now south-eastern Australia, a new study has found.

Research published in PLoS ONE describes the findings of scientists and volunteers from Monash University and Museum Victoria who uncovered a higher than expected biodiversity of meat-eating, theropod (bird-like) dinosaur fossils from between 105 and 120 million years ago.

Honorary Research Fellow Dr Tom Rich has lead the team collecting dinosaur fossils from the Otway and Stzelecki Ranges of south Victoria for 30 years with colleagues Lesley Kool, Dave Pickering and Professor Pat Vickers-Rich.

The team is associated with both Monash University’s School of Geosciences and Museum Victoria.

“We had not expected to find fossils from such a large range of dinosaur species in this area. The fossils we have collected range from tiny, cat-sized killers to Australia’s version of T. Rex, a nine-metre-long predator with powerful arms and razor-sharp claws,” Dr Rich said.

“In total 1500 isolated bones and teeth of various kinds of dinosaurs have been found in Victoria, Australia so far. Their meaning is only beginning to be unravelled by detailed study and comparisons with other fossils world-wide.”

At the time these dinosaurs ruled, southern Australia was part of the Antarctic Circle. Despite the cold, there was a high diversity of small predators, similar to the Velociraptor, featured in Jurassic Park.

“One of the reasons for the success of small, theropod dinosaurs may be their warm-blood. As close relatives of birds, they had feathery insulation which helped maintain high body temperatures,” Dr Rich said.

“The cool, damp climate may also explain the discovery of the same dinosaur species in both Australia and the northern continents.”

The study released in PLoS ONE by University of Cambridge researchers is focused on the discovery of these meat-eating theropod dinosaurs.

Dr Roger Benson, from the University of Cambridge, said the study reports new discoveries and rationalises previous investigations.

Editor's Note: Original news release can be found here.

Parks key to physical activity

Wed, 16 May 2012 15:42:33 GMT

The research found that more people exercised at parks after they'd been upgraded.

Image: oversnap/iStockphoto

Improving community health could lie in the quality of neighbourhood parks, a Deakin University study has found.

Health researchers with Deakin’s Centre for Physical Activity and Nutrition Research examined whether improvements to parks increased usage and park-based physical activity of users. They found significant increases in the number of visitors and levels of exercise undertaken at one park after the facilities had been upgraded.

“Parks are important places for people to spend their leisure time and be physically active,” explained Deakin health researcher Dr Jenny Veitch.

“Understanding how we can attract residents to spend time at local parks and encourage them to be more physically active is an important public health initiative. This is particularly the case in disadvantaged neighbourhoods where residents are at increased risk of being inactive which can lead to poor health.”

For the study, the researchers examined two parks in the same neighbourhood, one of which was about to be refurbished. Both parks were similar in size and mostly open spaces with few amenities. Upgrades to the one park included a fenced dog park, an all-abilities playground, walking track, barbeque area, landscaping and fencing. How many people used the parks and their levels of activity were monitored three months before the park improvements, three months after the improvements and one year later.

The results of the study point to the positive effect improving facilities can have on usage and the types of physical activity undertaken within local parks.

“We found that four times more people used the upgraded park a year after the changes, with more people walking and engaging in vigorous activities such as running or playing ball sports. While less people used the unchanged park and the activity levels remained pretty much the same,” Dr Veitch said.

“What our study has shown is that improving existing parks can encourage people to make use of the facilities and increase their levels of physical activity.

“The findings have implications for future park-renewal projects and can help urban planners and designers to develop parks that attract users and facilitate greater levels of physical activity.”

The results of this study are published in the American Journal of Preventive Medicine.

Editor's Note: Original news release can be found here.

Sea lions fuel ocean life

Wed, 16 May 2012 15:37:43 GMT

The bacteria in the faeces of sea lion are capable of making iron and phosphorous available to phytoplankton, the research found.

Image: zimdingo1/iStockphoto

Like whales, sea lions are contributing to marine ecosystems in the most fundamental way possible, research by a Flinders graduate has found.

Dr Trish Lavery, who established that Southern Ocean sperm whales offset their carbon emissions by defecating iron on phytoplankton, has found that the digestive mechanisms of Australian sea lions mean that they too are making vital nutrients available to the first tier of the marine food chain.

Her research, published in the Public Library of Science journal PLoS ONE, found that the sea lion gut has a characteristic microbiome, or bacterial profile, that is high in types of bacteria able to metabolise iron and phosphorus.

“While bacteria are net consumers of nutrients in energy-poor environments, in nutrient-rich environments like the surface of a faecal particle, bacteria can make soluble more vital nutrient elements from faecal matter than they require for their own growth,” Dr Lavery said.

“This leads to leaching of these nutrients into the surrounding waters where they can become available for free living phytoplankton microbes.”

Dr Lavery said the sea lions may therefore help to keep nutrients where they can be incorporated into the food chain.

“The bacteria in Australian sea lion faeces may limit nutrient sinkage to depth and enhance the persistence of nutrients in the photic zone where they are available to support primary production by phytoplankton.”

And for creatures whose cold marine environment makes a layer of protective fat a valuable asset, Dr Lavery also found evidence that the metabolism of sea lions is actually geared towards obesity.

Her study found a ratio of crucial bacteria similar to that in previous studies of obese humans and obese mice.

“This suggests that the gut microbiome may confer a predisposition towards the excess body fat that is needed for thermoregulation within the cold oceanic habitats foraged by Australian sea lions,” she said.

Editor's Note: Original news release can be found here.

Fastest growing volcano found

Wed, 16 May 2012 15:32:09 GMT

The Monowai Cone grew around 8.5 million cubic metres in three weeks, the fastest volcanic growth ever recorded.

Image: GNS Science

Scientists have found a submarine volcano in New Zealand waters that has undergone the fastest episode of collapse and growth ever recorded at a volcano.

The Monowai Cone, part of the Monowai Volcanic Centre, is a giant submarine volcano about 1,000km northeast of the North Island that underwent a mighty geological upheaval during five days in mid-2011, and provided scientists with new insights into the behaviour of submarine volcanoes.

The volcano added about 8.5 million cubic metres of lava and debris to its summit during the brief period it was under observation.

The newly erupted material raised the summit area by 79m, while a collapse at another part of the summit saw a sudden height reduction of 19m. The volcanic growth structures included at least four new summit cones.

The observations were made unexpectedly during a three-week survey of the volcanoes in the Kermadec Arc from the German research ship Sonne.

The findings have been published this week in the prestigious science journal Nature Geoscience. One of the joint authors of the paper was marine geologist, Cornel de Ronde of GNS Science.

“The rate of change we observed is a reminder of how rapidly geological processes such as submarine volcanism and landsliding can occur.”

Dr de Ronde said as well as providing insights into the dynamics of seafloor volcanism, the observations had implications for geohazards such as tsunami.

“It’s well documented that any sudden displacement of the seabed has the potential to trigger a tsunami. Submarine landslides and submarine volcanism can set off a tsunami that can travel across the ocean,” he said.

Monowai is one of the most active submarine volcanoes in the Tonga-Kermadec arc, a 2500km-long chain of submarine volcanoes stretching from New Zealand to just north of Tonga.

Geophysical surveys from research ships dating back to the early 1980s had shown regular and significant changes to the summit area of Monowai. But the changes observed in mid-2011 were the most dramatic and rapid seen to date.

The scientists estimated that in a four-year period starting in 2007, Monowai volcano could have undergone up to a dozen growth and collapse phases.

The scientists suspected a growth spurt was underway when they approached Monowai on the Sonne in May 2011 and observed discoloured seawater and gas bubbles rising above the volcano.

During this period, seismic stations at several Pacific Island locations, including the Cook Islands, recorded a five-day swarm of shallow earthquakes located at Monowai.

When the Sonne returned to Monowai later in the three-week voyage, the scientists found part of the Monowai summit had collapsed and another part had grown substantially.

The new material at the summit was most likely erupted ash and volcanic debris, Dr de Ronde said.

The scientists believe the rapid changes they observed were larger than at most other volcanoes. Only Mount St Helens and Mount Vesuvius had recorded larger growth rates.

“The rate of change we observed is a reminder of how rapidly geological processes such as submarine volcanism and landsliding can occur.”

Dr de Ronde said the rapid growth rates at Monowai helped to shed light on the factors that controlled the ‘emplacement of surface magma’ at submarine volcanoes.

The contributing factors included the gas content of the magma, the upward pressure regime, crustal thickness, the tectonic setting, and local stress field.

“It’s remarkable that we were able to capture such dramatic geomorphic changes on the seafloor within the duration of a single research voyage.”

Editor's Note: Original news release can be found here.

'Spell check' for DNA developed

Wed, 16 May 2012 15:24:54 GMT

Machine errors in gene sequencing can cause biologists to misinterpret which genes or microbial species are in their samples. The new software will help to pick up these errors.

Image: dra_schwartz/iStockphoto

A PhD student from CSIRO and The University of Queensland has found a better way to 'spell check' gene sequences and help biologists better understand the natural world.

The student, Lauren Bragg, is a member of the Australian Centre for Ecogenomics, which sits within UQ's School of Chemistry & Molecular Biosciences.

Along with her co-authors, Lauren has contributed to the May issue of the prestigious journal Nature Methods highlighting her new approach and its software implementation called Acacia.

Acacia analyses the output of next-generation gene sequencing instruments which read the four-letter alphabet of As, Cs, Ts and Gs – the 'bases' that code for DNA and spell out the genes of different living organisms. Acacia specifically applies to important parts of microbe genes called amplicons.

Just as a computer spell checker finds typing errors in words, so Acacia finds errors in the DNA code of amplicon sequences produced during gene sequencing.

Acacia shows clear improvements over the two error-correction tools currently used by biologists for amplicon sequences and it's easier for biologists to use.

Lauren's development of Acacia is part of the field of bioinformatics, a blend of computer science, statistics and biology. Despite her surname, however, she is modest about her achievements.

"It's exciting to be published in a journal like Nature Methods but I get more satisfaction from hearing how my software is helping biologists fix sequencing errors," she said.

Machine errors in the long lengths of A, C, G and T code can cause biologists to misinterpret which genes are there, or which microbial species might exist in a environmental samples from, say, a waste water treatment plant or from the ocean or even our guts.

Acacia works by using the statistical theory of likelihoods to analyse the code for DNA bases which may have been mistakenly added or deleted – common errors in gene sequencing.

"The Nature article is our way of telling the international biology community that there's a new software tool they can use for error-correcting that's pretty easy to use, quick and reliable."

"That way, they won't think they've discovered a new microbe species when they haven't or overlooked one they should have found," she said.

The method, or algorithm, that Acacia uses took 18 months for Lauren to fully develop and test.

Now it's nose to the grindstone to get the thesis done.

Editor's Note: Original news release can be found here.

Coral model predicts bleaching

Wed, 16 May 2012 15:09:23 GMT

Coral bleaching can devastate reefs and the animals that rely on them. The new model takes into account coral porosity, shape, size, water flow and heat transfer to predict where bleaching will occur.

Image: RainervonBrandis/iStockphoto

Curtin University researchers have used computational fluid dynamics and powerful supercomputers to create new models for understanding and predicting coral bleaching.

A phenomenon that has increased in magnitude over the past two decades, coral bleaching is attributed to an elevation of sea surface temperatures combined with the sun’s irradiation.

While bleaching is generally expected in response to a one to two degree temperature increase over a prolonged period, the new models consider phenomena such as coral porosity and permeability, morphology, mass and most importantly water flow and heat transfer.

Dr Ben Mullins of Curtin’s Fluid Dynamics Research Group said due to their shape and surface area, some corals are likely to be more susceptible to bleaching.

“One of the elements ignored until now is water flow, which can significantly influence the thermal microenvironment of the coral as water flows through and around it,” he said.

“Basically, we’ve taken an engineering approach to an issue that biologists have been looking at for years and come up with a completely new method to predict how much corals warm.”

He said outcomes from the computer models were shown to be consistent with outcomes from laboratory experiments, indicating validity of the new approach.

“The models have the advantage of providing three-dimensional temperature and flow information down to very precise resolution compared to previous methods reliant on microprobes,” he said.

“They are also sufficiently flexible to accommodate large-scale in-situ modelling.”

Dr Mullins said the next step was to apply the models more broadly to entire coral reefs.

“Given the scale of these structures, it’s very hard to get good data out in the field,” he said.

“Traditionally, researchers have measured temperature and flow at different points, which isn’t an accurate representation of the larger system.

“Our models are much more comprehensive.

“Given that the Great Barrier Reef is worth $6 billion from tourism alone to the Australian economy, there’s immense value in reef conservation.”

Coral consist of a calcite skeleton with a layer of living tissue. They live in a symbiotic relationship with zooxanthellae, single-celled plants/algae, with both providing nutrients for survival.

Coral bleaching occurs when zooxanthellae are expelled by coral or lose their pigmentation. Under some circumstances coral can recover, but in most cases they die.

Published in PLoS One, the research was spearheaded by Curtin’s Fluid Dynamics Research Group with the Australian Institute of Marine Science. The work was made possible through use of the iVEC@Murdoch supercomputer, Epic, via OpenFOAM software.

Editor's Note: Original news release can be found here.

Nano-devices need flat surface

Tue, 15 May 2012 15:49:32 GMT

Scanning electron microscope image: the 'table' is the green region. The 'pockets' are narrowings that join to open green areas, the 'cushion' is the grey trench that defines the device. White scale bar is 500 nanometres.

Image: UNSW

There’s nothing worse than a shonky pool table with an unseen groove or bump that sends your shot off course: a new study has found that the same goes at the nano-scale, where the “billiard balls” are tiny electrons moving across a “table” made of the semiconductor gallium arsenide.

These tiny billiard tables are of interest towards the development of future computing technologies. In a research paper titled “The Impact of Small-Angle Scattering on Ballistic Transport in Quantum Dots”, an international team of physicists has shown that in this game of “semiconductor billiards”, small bumps have an unexpectedly large effect on the paths that electrons follow.

Better still, the team has come up with a major redesign that allows these bumps to be ironed out. The study, led by researchers from the UNSW School of Physics, is published in the journal Physical Review Letters.

The team included colleagues, from the University of Oregon (US), Niels Bohr Institute (Denmark) and Cambridge University (UK).

“Scaled down a million-fold from the local bar variety, these microscopic pool tables are cooled to just above absolute zero to study fundamental science, for example, how classical chaos theory works in the quantum mechanical limit, as well as questions with useful application, such as how the wave-like nature of the electron affects how transistors work,” says team member Associate Professor Adam Micolich. “In doing this, impurities and defects in the semiconductor present a serious challenge.”

Ultra-clean materials are used to eliminate impurities causing backscattering (akin to leaving a glass on the billiard table) but until now has been no way to avoid the ionized silicon atoms that supply the electrons.

“Their electrostatic effect is more subtle, essentially warping the table’s surface.” explains Micolich.

Earlier studies assumed this warping was negligible, with the electron paths determined only by the billiard table’s shape (e.g. square, circular, stadium-shaped).

“We found that we can ‘reconfigure’ the warping by warming the table up and cooling it down again, with the electron paths changing radically in response,” says Professor Richard Taylor from the University of Oregon. “This shows that the warping is much more important than expected.”

Using a new billiard design developed during PhD work at UNSW by lead author Dr Andrew See, the silicon dopants are removed, eliminating the associated warping, and enabling the electron paths to stay the same each time they cool the device down for study.

“These undoped billiard devices pinpoint the silicon dopants as the cause of the warping. The level of improvement obtained by removing the silicon was unexpected, earlier work on much larger devices suggested that we wouldn’t see this level of improvement.

But at the nanoscale, the dopant atoms really do make a really big difference”, says Micolich, “Ultimately, our work provides important insight into how to make better nanoscale electronic devices, ones where the properties are both more predictable, and more consistent each time we use them.”

Editor's Note: Original news release can be found here.

Early epilepsy hints at future

Tue, 15 May 2012 15:43:45 GMT

The research showed that epilepsy followed a pattern based on how a person responds to initial treatment.

Image: Nic_Taylor/iStockphoto

How well people with newly diagnosed epilepsy respond to their first drug treatment, may signal the likelihood that they will continue to have uncontrolled seizures according to University of Melbourne Chair of Neurology Professor Patrick Kwan.

In a study published in Neurology, the medical journal of the American Academy of Neurology, Professor Kwan, who is also head of the clinical epilepsy program at the Royal Melbourne Hospital and an international authority in antiepileptic drug development, believes a pattern emerges in the early stages.

“Our research shows a pattern based on how a person responds to initial treatment and specifically, to their first two courses of drug treatment,” said Dr Kwan.

For the study, 1,098 people from Scotland between the ages of nine and 93 with newly diagnosed epilepsy were followed for as long as 26 years after being given their first drug therapy. Participants were considered seizure-free if they had no seizures for at least a year without changes in their treatment. If they had further seizures, a second drug was chosen to be given alone or to be added to the first. If seizures continued, a third drug regimen was selected, and the process continued for up to nine drug regimens.

The study found that 50 percent of the people were seizure-free after the first drug tried, 13 percent were seizure-free after the second drug regiment tried and 4 percent were seizure-free after the third. Less than two percent of the participants stopped having seizures on additional drug treatment courses up to the seventh one tried, and none became seizure-free after that.

The research also found that 37 percent of people in the study became seizure-free within six months of treatment. Another 22 percent became seizure-free after more than six months of starting treatment. Both groups continued to be seizure-free. However, 16 percent had fluctuating periods of seizure freedom and relapses, and 25 percent were never seizure-free for one year.

At the end of the study, 749 people (68 percent) were seizure-free and 678 people (62 percent) were on only one drug. The results were independent of the age when the person had the first seizure or the type of epilepsy.

“A person who doesn’t respond well to two courses of epilepsy drug treatment should be further evaluated to verify an epilepsy diagnosis and to identify whether surgery or other treatment modalities is the best next step,” said Professor Kwan. “While freedom from seizures is the goal of treatment, we still have to consider quality of life issues for each individual patient.”

Affecting 50 million people worldwide, epilepsy is the most common serious neurological disorder and a major global public health issue. Identifying drug resistance promptly and understanding the genetic risk factors predisposing to epilepsy and drug resistance can help doctors find better treatment and potentially preventive therapy.

Editor's Note: Original news release can be found here.

Pregnancy warning sign found

Tue, 15 May 2012 15:33:38 GMT

Pre-eclampsia currently develops without warning and can do long term damage to a baby.

Image: Moncherie/iStockphoto

An indication of whether a mother will develop pre-eclampsia, the most common and severe pregnancy-related disease, has been identified by a University of Sydney study.

The findings, published in the latest edition of the Journal of Reproductive Immunology, could allow the early detection of pre-eclampsia, which currently cannot be diagnosed by symptoms before the disease occurs.

The research also suggests the womb may have a lasting impact on a child's immune system.

"Pre-eclampsia affects an estimated 5000 to 10,000 women in Australia every year," said Professor Ralph Nanan, senior author of the study, from Sydney Medical School Nepean.

It develops in mothers out of the blue, usually in the last three months of pregnancy, causing high blood pressure, kidney and liver damage and severe blood changes. Delivering the baby as soon as possible is the only way to stop it."

In pre-eclampsia the mother's immune system appears to attack the fetus.

"Our study looked at the thymus of the fetus, a structure which sits behind the baby's breastbone and is known as the 'cradle' of an important set of white blood cells called thymus-derived lymphocytes or T cells," said Professor Nanan.

No previous study has looked at the effect of the disease on the fetal organ systems.

"Surprisingly we found the thymus of babies whose mother developed pre-eclampsia was significantly smaller than in babies of healthy pregnant women."

What further surprised the researchers was that these changes were obvious in mid-pregnancy, long before the mother developed any signs of pre-eclampsia.

"This is a very interesting finding as the thymus plays a central role in shaping the child's immune system and protecting it against the development of allergies, autoimmune disease and cancers later in life," Professor Nanan said.

The group is now conducting a prospective study with over 1200 pregnant women to confirm the findings with the long-term prospect of developing a test for pre-eclampsia. It is also conducting studies which aim to describe the short and long-term effects that early thymus changes have on the child's immune system and on the development of immune diseases.

The study was conducted by David Eviston, Ann Quinton and a team of researchers from Sydney Medical School Nepean.

Editor's Note: Original news release can be found here.

Discovery may delay dementia

Mon, 14 May 2012 16:00:25 GMT

The molecule fractalkine may underpin future dementia therapies, according to the researchers.

Image: GuidoVrola/iStockphoto

Scientists at The University of Queenlsand's Queensland Brain Institute are one step closer to developing new therapies for treating dementia.

QBI's Dr Jana Vukovic said the work was aimed at understanding the molecular mechanism that may impair learning and memory in the ageing population.

“Ageing slows the production of new nerve cells, reducing the brain's ability to form new memories,” said Dr Vokovic, who performed the work in the laboratory of Professor Perry Bartlett, the Director of QBI at The University of Queensland.

"But our research shows for the first time that the brain cells usually responsible for mediating immunity, microglia, have an inhibitory effect on memory during ageing.

“Furthermore, they have shown that a molecule produced by nerve cells, fractalkine, can reverse this process and stimulate stem cells to produce new neurons.”

The discovery, published in The Journal of Neuroscience, came after QBI scientists observed that the increased production of new neurons in mice that were actively running was due to the release of fractalkine in the hippocampus – the brain structure responsible for specific types of learning and memory.

Professor Bartlett said it had been known for some time that exercise increased the production of new nerve cells in the hippocampus in young and even aged mice.

“But this study found that it is fractalkine that appears to be specifically mediating this effect by making the microglia produce factors that activate the stem cells that produce new nerve cells,” he said.

“Once the cells are activated they divide and produce new cells, which underpin the animal's ability to learn and form memories.

"This means that fractalkine may form the basis for the development of future therapies.

“The discovery is especially exciting because we have found that older animals suffering cognitive decline showed significantly lower levels of fractalkine.

“We are seeking ways of increasing fractalkine levels in patients with cognitive decline, and hoping this may be a new frontline therapy in treating dementia.”

Dr Vukovic said that until relatively recently, it was thought the adult brain was incapable of generating new neurons.

“But work from Professor Bartlett's laboratory over the past 20 years has demonstrated that the brains of adult animals, including humans, retain the ability to make new nerve cells,” she said.

“The challenge is to find out how to stimulate this production in the aged animal and human where production has slowed.”

The latest work was a significant step toward achieving this goal, she said.

The article published is titled "Microglia modulate hippocampal neural precursor activity in response to exercise and aging". Its authors are Jana Vukovic, Michael J. Colditz, Daniel G. Blackmore, Marc J. Ruitenberg, Perry F. Bartlett.

Editor's Note: Original news release can be found here.

Bees may improve robot vision

Sun, 13 May 2012 15:47:43 GMT

The research shows that a honeybee brain is sophisticated enough to learn rules and process visual problems, suggesting a robot could one day do the same.

Image: Antagain/iStockphoto

An international research breakthrough with bees means machines might soon be able to see almost as well as humans.

The Australian and French research shows that honeybees use multiple rules to solve complex visual problems.

Study author Dr Adrian Dyer, from RMIT University, said the findings held important implications for our understanding of how cognitive capacities for viewing complex images evolved in brains.

Dr Dyer said that rule learning was a fundamental cognitive task that allowed humans to operate in complex environments.

“For example, if a driver wants to turn right at an intersection then they need to simultaneously observe the traffic light colour, the flow of oncoming cars and pedestrians to make a decision,” he said.

“With experience, our brains can conduct these complex decision-making processes, but this is a type of cognitive task beyond current machine vision.

“Our research collaboration between labs in Australia and France wanted to understand if such simultaneous decision making required a large primate brain, or whether a honeybee might also demonstrate rule learning.”

Dr Dyer said the research team lead author Dr Aurore Avargues-Weber (Université de Toulouse) trained individual honeybees to fly into a Y-shaped maze which presented different elements in specific relationships like above/below, or left/right.

With extended training the bees were able to learn that the elements had to have two sets of rules including being in a specific relationship like above/below, while also possessing elements differing from each other.

Dr Dyer said the findings showed that possessing a large complex brain was not necessary to master multiple simultaneous conceptual rule learning.

“This offers the possibility of deciphering the neural basis of high-level cognitive tasks due to the simplicity and accessibility of the bee brain,” he said.

The research was published last month in the Proceedings of the National Academy of Sciences of the United States of America.

Editor's Note: Original news release can be found here.

Study: meditation boosts health

Sun, 13 May 2012 15:43:03 GMT

The biggest difference was in mental health, where long-term meditators were more than 10% better off than the rest of the population.

Image: shironosov/iStockphoto

The experience of 'mental silence' is linked with better health outcomes and greater wellbeing according to a University of Sydney study.

The area of greatest difference was in mental health, where long-term meditators, with a minimum of two years of regular practice, were more than 10% better off than the general population.

"We found that the health and wellbeing profile of people who had meditated for at least two years was significantly higher in the majority of health and wellbeing categories when compared to the Australian population," said Dr Ramesh Manocha, Senior Lecturer in the Discipline of Psychiatry, Sydney Medical School, who led the research.

He worked with Professor Deborah Black and Dr Leigh Wilson from the Faculty of Health Sciences.

"Most markedly there was a robust relationship between the frequency of experiencing mental silence and better mental health. This definition is based on it being the form of meditation practised for centuries."

The national study is a world-first health quality-of-life survey of long-term meditators. It used the same measurement instruments as the one used by the federal government's National Health and Wellbeing Survey.

More than 350 people from across Australia who have meditated for at least two years were assessed for the national study which has been published in the journal of Evidence-Based Complementary and Alternative Medicine.

"We focused on the definition of meditation as mental silence and surveyed practitioners of Sahaja Yoga meditation who practise a form of meditation aimed at achieving this state rather than relaxation or mindfulness methods that are usually the focus of other forms," Dr Manocha said.

The meditators were asked how often they experienced 'mental silence' for more than a few minutes at any one time.

Fifty-two percent of respondents said that they experienced mental silence "several times per day or more" while 32 percent were experiencing it "once or twice per day".

"Our analysis showed very little relationship at all between how often the person who meditated physically sat down to meditate and mental health scores. However the relationship was clearly apparent in relation to how often they experienced the state of mental silence.

"The health advantage appears to be connected to this aspect more than any other feature of the meditation lifestyle. In other words it is quality over quantity.

"While we did expect that there would be some differences between the meditators and the general population we didn't expect the findings to be so pronounced. We repeated large components of the survey several times to confirm our results and got the same outcomes."

The Australian government survey give a numerical score to each facet of mental and physical health and because it has been applied as a national measure for the past 10 years in studies around the world involving millions of people. It allowed the researchers to accurately compare the health profile of the meditators surveyed with the general Australian population.

The meditators were primarily non-smokers and non-drinkers, so to adjust for that potential bias the researchers also compared the meditators to those parts of the Australian population who did not drink or smoke, and achieved the same results.

"This is one of the first studies to assess the long term health impacts of meditation on health and wellbeing. When we take the evidence of this study, along with the results of our other clinical trials, it makes a strong case for the use of meditation as a primary prevention strategy, especially in mental health," Dr Manocha said.

Editor's Note: Original news release can be found here.

Colourful birds evolve faster

Sun, 13 May 2012 15:38:50 GMT

The theory that colourful bird species evolve faster was proposed in the 1950s by famous scientists such as Julian Huxley, but this is the first study to confirm it.

Image: Smileyjoanne/iStockphoto

Researchers have found that bird species with multiple plumage colour forms within in the same population, evolve into new species faster than those with only one colour form, confirming a 60 year-old evolution theory.

The global study used information from birdwatchers and geneticists accumulated over decades and was conducted by University of Melbourne scientists Dr Devi Stuart-Fox and Dr Andrew Hugall (now based at the Melbourne Museum) and is published in the journal Nature.

The link between having more than one colour variation (colour polymorphism) like the iconic red, black or yellow headed Gouldian finches, and the faster evolution of new species was predicted in the 1950s by famous scientists such as Julian Huxley, but this is the first study to confirm the theory.

By confirming a major theory in evolutionary biology, we are able to understand a lot more about the processes that create biodiversity said Dr Devi Stuart-Fox from the University’s Zoology Department.

“We found that in three families of birds of prey, the hawks and eagles, the owls and the nightjars, the presence of multiple colour forms leads to rapid generation of new species,” Dr Stuart-Fox said.

“Well known examples of colour polymorphic species in these families include the Australian grey goshawk which has a grey and pure white form, the North American eastern screech owl and the Antillean nighthawk, each with grey and red forms.”

The team focused on birds because although colour polymorphism occurs in many animals (such as fish, lizards, butterflies and snails), there is a wealth of information on colour variation in birds, as well as on species classification (taxonomy), partly thanks to birdwatchers or ‘twitchers’.

“We looked at five bird families with a high proportion of colour polymorphism and compared their rates of evolution with those with only one colour form,“ Dr Stuart-Fox said.

By modeling evolutionary rates using publicly available genetic information accumulated over a quarter of a century, the study found that colour polymorphism speeds up the generation of new species. Colour polymorphic species tend to evolve into species with only one colour form (monomorphic), explaining why existing species with different colour forms are relatively young and also rare.

The study found that colour polymorphic species were younger not only in the birds of prey but in the songbirds, which account for more than half of the world’s bird species.

Study co-author Dr Andrew Hugall noted that when scientists like Julian Huxley proposed that colour polymorphism speeds up the generation of new species over half a century ago, they did not have the huge amounts of data needed to support it.

“Using many decades of natural history information and 25 years of genetic sequence information we were able to generate the massive family trees, such as a tree of more than four thousand songbirds, needed to model rates of bird evolution in this study,” he said.

“Now that we’ve identified this pattern for the first time, our next step is to test some of the explanations proposed for why colour polymorphism leads to accelerated evolution.”

Editor's Note: Original news release can be found here.

Infrared light stops eye damage

Sun, 13 May 2012 15:32:48 GMT

People with careers that expose them to bright light, such as construction workers, fishermen, welders or actors, could be pre-treated with infrared light to reduce vision damage.

Image: Jasmina81/iStockphoto

Treating eyes with gentle infrared light can help prevent the damage caused by subsequent exposure to bright light, new scientific research has found.

A breakthrough by researchers at Australia's Vision Centre offers new hope to people who suffer vision loss due to constant exposure to bright sunlight or artificial lights – such as construction workers, sportspeople, fishermen, farmers, welders, actors, entertainers and others.

Dr Krisztina Valter and PhD researcher Rizalyn Albarracin at The Vision Centre and Australian National University have shown that pre-treatment with near infrared light prevents a build-up of scar tissue in the retina causing subsequent harm to sight.

“There’s a group of cells that look after our vision and work behind the scenes called Müller cells," says Ms Albarracin. "They act to protect the retina by clearing toxins and inducing healing whenever there is injury to the vision cells.”

“However, their protection is a double-edge sword for the eyes. When the retina comes under extreme stress, as when it is exposed to intensely bright light and loses a large number of vision cells, the Müller cells can over-react by multiplying and forming scar tissue behind the retina,” she says.

“When this occurs, two things happen: first, the vision cells close to where the scar tissue forms will stop working.

“Secondly, the scar tissue blocks the blood supply to the outer retina, so that other vision cells are starved of oxygen, glucose and other nutrients vital to their survival.

“As a result more vision cells die, which in turn provokes Müller cells to work even harder, forming more scar tissues and setting up a vicious cycle,” Ms Albarracin explains.

“We found that the treatment with mild NIR successfully inhibits the Müller cells from multiplying and forming scar tissue,” says team leader Dr Krisztina Valter.

“Technically, our results showed that 670 nm light pretreatment ameliorates light-induced changes in the expression of Müller-cell specific markers for structure, stress, metabolism and inflammation.

“This suggests that 670 nm light pre-treatment may promote neuroprotective effects in the retina from light-induced damage.

“Our findings indicate that it may be possible to pre-treat someone who knows that they will be exposed to bright lights and so reduce the potential damage it can cause.

“This would be very helpful for people working in bright sunlight, under powerful artificial lamps or in occupations such as welding, as it would reduce the amount of cumulative damage they can suffer to their vision of years of exposure to bright light,” Dr Valter says.

The researchers used an array of small LEDs (light emitting diodes) that have been tuned to produce near infrared light at a specific wavelength – 670 nanometres.

These units are low-cost, making a future preventative treatment for vision loss highly affordable – especially when compared with cost of lost sight, Dr Valter says.

“Near infrared therapy is very benign, easy to use and involves no discomfort to the patient,” she adds. “It is already approved by the US Food and Drug Administration for use in sports medicine, for hair loss and so on – so developing a novel therapeutic application for the eyes is likely to be less complex and protracted than, say, developing a new drug,” she adds.

The study “670nm Red Light Preconditioning Supports Müller Cell Function: Evidence from the White Light-induced Damage Model in the Rat Retina” by Rizalyn Albarracin and Krisztina Valter is published in the journal Photochemistry and Photobiology.

The Vision Centre is funded by the Australian Research Council as the ARC Centre of Excellence in Vision Science.

Editor's Note: Original news release can be found here.

OPINION: Surprise! Facial expressions aren’t necessarily universal

Thu, 10 May 2012 14:25:50 GMT

Is this man surprised or afraid? Your opinion may be influenced by where you grew up, research suggests.

Image: AndyL/iStockphoto

You can tell a lot about a person’s emotional state by looking at their face. A quick glance can give you an idea of whether a person is, say, happy or angry, allowing you to modify your behaviour accordingly.

The rapid and accurate recognition of some emotional states – particularly fear or anger – would have been advantageous in our evolutionary history. For instance, being able to determine when someone is angry with you might give you time to run away before they attack.

For this reason, you might think the way emotions are expressed on the face would be the same across all races and not substantially influenced by culture.

But new research, published in the Proceedings of the National Academy of Sciences by psychologist Rachael Jack and colleagues seems to show this isn’t the case.

What are you looking at?

Facial expressions are produced by the movement of facial muscles, with distinct patterns of movement thought to convey certain expressions.

For instance, the activation of the zygomaticus major muscles leads to an upturned mouth and activation of the orbicularis oculi muscles enhances creases around the eyes, both of which are often associated with happiness.

It is often claimed there are at least five discrete, basic emotions – anger, happiness, disgust, sadness, fear – and perhaps more (surprise and contempt), each with their own characteristic facial expression.

One of the first to propose a limited number of biologically based and universal expressions was Charles Darwin in 1872, in The Expression of the Emotions in Man and Animals.

And there is strong support for this position. Certain facial expressions appear in a similar form in humans and primates, as well as infants and young children.

These same facial expressions are even depicted in identical ways by people who are born blind (that is, without the ability to see and copy expressions).

But perhaps the most convincing evidence in support of Darwin’s universality hypothesis came a century after it was first proposed, with psychologist Paul Ekman’s research on cross-cultural facial expression recognition.

Ekman and colleagues demonstrated that a preliterate culture in Papua New Guinea, the Fore, as with 21 literate cultures also studied, could label facial expressions representing anger, happiness, sadness and disgust (although they could not discriminate between surprise and fear).

The Fore also generated facial expressions of basic emotions that were well recognised by other cultures.

Therefore, it seems the capacity to generate and recognise these basic expressions was not learned through media or other social influences. Instead, it had developed in isolation, providing compelling evidence in support of the universality hypothesis.

But Ekman’s research has not been without its critics. Over the past four decades there has been considerable debate about whether facial expressions of emotion are, in fact, universal or whether they are instead shaped by one’s culture.

Which brings us back to the research of Rachael Jack and colleagues.

Their paper, unambigiously titled Facial expressions of emotion are not culturally universal, casts doubt on the universality hypothesis.

Faces on a screen

Jack and colleagues created a computer program that randomly generated thousands of 3D facial movements, some of which formed characteristic patterns of facial expressions (see video below).

Observers, half of whom were Western Caucasian and half East Asian (with little experience of each other’s culture), were asked to categorise each animation as one of six basic emotions – anger, happiness, fear, sadness, disgust or surprise – or “other”, and judge the emotional intensity of each animation.

For Western Caucasian observers, the facial movements categorised as each of the six basic emotions appeared distinct and all observers identified the same emotions.

By contrast, these same distinct movements were not seen in the categorisations made by East Asians, who showed a high degree of overlap in the categorisation of certain movements. This was particularly the case between fear and surprise, as well as anger and disgust.

Other differences were also apparent between the observations of Western Caucasians and East Asians. In particular, the perception of emotional intensity in some expressions was cued by rapid changes to the eye region for East Asians, whereas Western Caucasians took their cues from other parts of the face.

This study, along with other research over the past decade, is forming a consistent argument: there are cultural differences in the kind of facial expression movements thought to constitute certain emotions.

Jack and colleagues argue that if facial expressions were once universal, they have since evolved. If this is the case, one can only wonder what kind of facial signals will evolve in the future to communicate not just internal emotions, but intentions and deceptions.

What then, does this mean for communication between cultures in our increasingly globalised world?

Well, it seems obvious that we can’t assume our facial expressions communicate the same meaning to everyone.

This in turn poses interesting questions: are the feelings that underlie our facial expressions also culturally diverse? Or is it merely the external depiction of our emotions, in the form of facial expressions, that have been shaped by culture?

As always, there is much still to learn.

Megan Willis is a Lecturer with the School of Psychology at Australian Catholic University. Romina Palermo is the Associate Professor with the ARC Centre of Excellence in Cognition and its Disorders & School of Psychology at University of Western Australia.

Editor's Note: This article was originally published by The Conversation, here, and is licenced as Public Domain under Creative Commons. See Creative Commons - Attribution Licence.

Anti-bacteria coating developed

Thu, 10 May 2012 14:16:57 GMT

The coating can be used to keep biomedical and consumer products free of bacteria without antibiotics, which no longer kill resistant 'superbugs'.

Image: Eraxion/iStockphoto

The superbugs have met their match.

Conceived at Nanyang Technological University (NTU), it comes in the form of a coating which has a magnetic-like feature that attracts bacteria and kills them without the need for antibiotics.

The killer coating, which has shown to destroy 99% of the bacteria and fungi that it comes in contact with, is now being used by two companies: a contact lens manufacturer and a company specialising in animal care products.

The next step is to extend its use in a wide range of biomedical and consumer products, ranging from implants and surgical instruments to kitchen utensils and cutlery, as it is harmless to human cells.

This is an alternative solution which could replace antibiotics - currently the main defence against bacteria - now powerless against super bugs.

The brainchild of Professor Mary Chan, Acting Chair of NTU’s School of Chemical and Biomedical Engineering, the coating made from Dimethyldecylammonium Chitosan methacrylate has earned a place in the prestigious international journal, Nature Materials.

This “sponge-like” polymer holds a positive charge, which acts as a magnet-type of force to draw in bacteria which has a negative charge on their cell walls. When the bacterium comes in contact with the coating, the cell walls are ‘sucked’ into the nanopores, causing the cell to rupture, thus killing the bacterium.

“The coating can also be applied on biomedical objects, such as catheters and implants to prevent bacterial infections, which is a serious cause of concern as many bacteria are now developing resistance to antibiotics - currently our main source of treatment for infections,” Prof Chan said.

“By developing novel materials which uses physical interaction to kill bacteria cells, we envisage this can be an alternative form of treatment for bacterial infections in the near future.”

Superbugs which had fallen prey to the coating include Pseudomonas aeruginosa, which can cause infections in the upper respiratory tract, gastrointestinal tract and the urinary tract; and Staphylococcus aureus, which can cause infections ranging from skin boils or abscesses to deadly diseases such as pneumonia and meningitis.

This research for a broad-spectrum antimicrobial coating was first sparked off by Prof Chan wanting to find an effective way to combat bacteria and fungi on contact lenses which could cause corneal infections (microbial keratitis) that could lead to permanent visual damage.

According to a 2006 study, the estimated annual incidence of a common fungi corneal infection, Fusarium keratitis, related to contact lens wear in Singapore is 2.35 per 10,000 wearers.

Building on the success of the antibacterial coating, Prof Chan and her doctoral student, Mr Li Peng, have now succeeded in making another broad-spectrum antimicrobial solution of a similar kind which is highly selective, killing off only bacteria and fungi without harming human cells in vitro.

Their research was published recently in a leading journal, Advanced Materials. This liquid material based on cationic antimicrobial peptidopolysaccharide, is a polymer which is attracted to microbial cell walls. When the two come into contact, the integrity of the cell wall is disrupted which leads to its rupture and death.

As this novel material kills cells via the destruction of cell walls, it makes it extremely difficult for bacteria to develop an effective resistance.

Prof Chan hopes to further develop this solution into topical applications such as cream and lotions, which can be used to disinfect and treat serious or chronic wounds such as lesions suffered by diabetic patients, killing any bacteria present that are resistant to antibiotics.

“Our long term goal is to develop this into an ingestible form, so it can effectively treat bacterial infections within the body, such as pneumonia and meningitis, replacing antibiotics as the standard treatment.” she added.

The two antimicrobial prototypes - the coating and the liquid solution - took a total of five years to research and costs over $800,000 to develop.

Prof Chan now aims to improve the liquid solution by developing it into a safe and proven antibiotic replacement within the next five years as the demand for such alternatives will be even higher with the rapid emergence of superbugs.

Editor's Note: Original news release can be found here.

Skin damage worst when young

Thu, 10 May 2012 02:38:09 GMT

The research suggests that in order to prevent wrinkles and skin damage, you need to protect your skin as a child.

Image: firemanYU/iStockphoto

Young people are at risk of suffering the worst skin damage they will receive during their lifetime, research from Queensland University of Technology (QUT) has found.

Researcher Professor Michael Kimlin from QUT's AusSun Research Lab said the study found UV exposure during a person's first 18 years of life was the most critical for cancer-causing skin damage and skin aging.

Professor Kimlin said while people aged over 50 had the slowest rate of skin degradation, results indicated that damage still occurred even at that age, so lifetime sun protection was important.

The study used a unique, non-invasive "UV camera", which took images of skin damage and aging invisible to the naked eye, to measure the relationship between lifetime sun exposure and skin cancer risk.

Professor Kimlin said the majority of skin damage occurred in the early years of sun exposure, with a much slower increase in damage in subsequent years over the age of 50.

"We looked at how age impacted on the skin damage we saw and found it's not a simple one to one relationship," said Professor Kimlin.

"The message from this research is to look after your skin when you are a child and teenager to prevent wrinkles and skin damage.

"Sun protection when you are young sets you on a lifetime of good skin health."

One hundred and eighty people aged 18 to 83 years old were imaged with the UV camera and interviewed to determine the level of their sun exposure.

The study measured hyperpigmentation of the skin to determine level of damage and wrinkles to indicate skin aging.

Professor Kimlin said using the UV camera meant people's skin could be examined for skin cancer risk factors without an invasive biopsy.

The research paper will be in the next edition of Science of the Total Environment and is available online here.

Editor's Note: Original news release can be found here.

Octopus hints at ice-sheet fall

Wed, 09 May 2012 14:45:25 GMT

The genetic evidence suggests that the West Antarctic Ice Sheet collapsed at one point - perhaps as recently as 200,000 years ago when global temperatures were warmer.

Image: Elaine Jorgensen/NOAA

Genetic evidence from an Antarctic octopus indicates that one of the world’s major ice sheets – the West Antarctic Ice Sheet – could collapse if global temperatures keep climbing.

octopusThe research has been published in the international journal Molecular Ecology and reported on Britain's Natural Environment Research Council (NERC) ‘Planet Earth’ website.

Lead author of the international study was Australian geneticist Dr Jan Strugnell from La Trobe University.

The team analysed the genes of the Turquet's octopus, which lives in the Southern Ocean surrounding Antarctica. Their work was carried out during the Census of Antarctic Marine Life, from 2005 to 2010, and International Polar Year in 2007.

Dr Strugnell told ‘Planet Earth: 'We were able to take advantage of much larger sample sizes than had been collected from Antarctica before. This presented us with a unique opportunity.’

She says adult Turquet's octopuses don't travel very much. They only move to escape from predators. However, the researchers found that the genes from octopuses from the Weddell and Ross Seas, 10,000 kilometres apart and on opposite sides of Antarctica, are startlingly similar.

'Those two seas are completely separate, so we expected the genetics of these octopuses to be quite different,' says Dr Strugnell.

However, because they are so similar, the researchers think this would only have happened if there had been a previous collapse of the West Antarctic Ice Sheet which separates those two bodies of water.

The British web site reports that this collapse may have happened possibly as recently as 200,000 years ago, which suggests that scientists' concerns about the state of today's ice sheet could well be justified.

Dr Strugnell says when the climate was much warmer, sea levels would have been substantially higher, because less water would have been locked up as ice. In this situation, the Ross and Weddell Seas could have been connected.

'Ocean currents both facilitate and hinder the flow of genes,’ she says. ‘But the Antarctic Circumpolar Current almost certainly wouldn't have facilitated so much dispersal by octopuses that two populations would have almost identical genetics if the ice sheet had been in place.’

The British web site said while a previous study, in 2010, provided the first evidence of a trans-Antarctic seaway connecting the Ross and Weddell Seas, this was the first genetic evidence of such a connection.

Climate scientists are interested in ice sheets because they lock away fresh water that would otherwise be added to the oceans and raise global sea levels.

Of the world's three major ice sheets, they think the West Antarctic is most vulnerable to rises in global temperatures. Many say the ice sheet is inherently unstable and could collapse fairly quickly, predicting a sea level rise by as much as five metres.

Editor's Note: Original news release can be found here.

Improved roots will boost crops

Tue, 08 May 2012 14:57:01 GMT

The study screened genetic variation in the root systems of lupins, and suggests that root improvement is the 'next frontier' of agriculture.

Image: KateLeigh/iStockphoto

Researchers at The University of Western Australia say that "next frontier" of agricultural science is understanding the root system and function of crop plants to significantly increase Australian grain production, keep farms viable and help continue to feed the world despite the onset of increasing drought and climate change.

In a project at The University of Western Australia, researchers experimented with lupin roots with an overall aim to improve the water use and nutrient uptake of narrow-leaf lupin varieties that account for half of all grain legumes produced in Australia - an industry worth more than $600 million a year.

The study, published this week in the international journal Plant Soil, warned that Australian grain producers faced increasing threats from poor local soils, harsh growing conditions and declining, less-predictable rainfall due to climate change.

To help address this, a team led by UWA-based Chief Investigators Winthrop Professor Zed Rengel and Winthrop Professor Kadambot Siddique used new screening techniques and advanced computer modelling to understand lupin root systems variability.

"We screened world's largest lupin genetic resource collection and identified tremendous genetic variation in lupin root systems," Professor Zed Rengel said.

"Our findings may be used in breeding new varieties of lupins with modified root system and function that may produce higher yields in soils with relatively limited water and nutrient resources."

Similar approaches could also be used to identify genetic variation in root system and function in Australian cereal crops such as wheat and barley, said Winthrop Professor Kadambot Siddique, Director of the Institute of Agriculture at The University of Western Australia.

Professor Siddique said climate change and increased risk of drought made it imperative for Australia to develop new ways to make crops more water and nutrient-efficient.

Roots efficient in acquiring soil resources (water and nutrients) are fundamental to growing high-yielding crops in Australian soils, but have been largely ignored by scientists - "it's the next frontier of agricultural science", he said.

"Traditional crop root systems are poorly suited to the harsh environmental conditions of Australian agriculture. Their inefficient use of water and fertilisers not only reduces yields but also increases salinity and algal blooms (eutrophication) in waterways due to excessive nutrient run-off.

"Farming terms of trade - commodity value relative to production cost - have declined consistently over time. Although this has been offset substantially by increased production efficiency, the onset of climate change may ultimately make farming unprofitable and threaten our ability to feed the world."

"Use of nitrogen and phosphorus fertilisers to grow crops in water-limited, nutrient-poor Australian soils is a big cost that will increase for grain producers as energy prices rise and rock phosphate stocks dwindle.

"Improved and more efficient root capture systems may cut costs and substantially increase Australian grain harvest yields, with the added benefit that better nitrogen uptake may also significantly improve grain quality.

The UWA-based study - in collaboration with the Western Australian Department of Agriculture and Food, Tasmanian Institute of Agricultural Research and US Pennsylvania State University - was funded by an Australian Research Council Discovery Project grant and paves the way for further similar research in wheat and barley.

Editor's Note: Original news release can be found here.