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By Stephen Luntz

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Distant Galaxies Rarer
Gravitational lensing is creating the impression that there were more galaxies in the early universe than actually existed, a paper in Nature has concluded.

Gravitational fields cause light to bend, and galaxies are powerful enough to bend light around them to form a lens, making distant objects brighter than they would otherwise be.

“There are only a few direct lines-of-sight to very distant objects in space,” says Prof Stuart Wyithe of the University of Melbourne’s School of Physics. “Our finding shows images from the earliest galaxies reach us more often via a gravitationally bent path. What you see is not exactly what is really there.”

The lens effect often distorts the shape of the galaxy, but more importantly means that cosmic censuses overestimate the number of galaxies appearing in the first 500 million years of the universe’s existence.

Wyithe says the finding does not overthrow models of the development of the universe: “The information we have about star formation this early in the universe is very meagre”. However, he thinks it is something that will need to be taken into account when the James Webb Space Telescope begins a much more detailed survey of the most distant galaxies.

Exercise Can Feed Unhealthy Cravings
An insight has been gained into why some people lose more weight from exercise than others. A/Prof Neil King of Queensland University of Technology found that for some overweight and obese people exercise increased the desire for fatty and sweet foods, while for other people it didn’t.

“What that told us is that exercise won’t work in the same way for everyone,” says King. “Some people lose weight equal to or more than the expected weight, whereas some people lose less weight than expected. We are now beginning to research and explain why they may not be able to lose the expected weight.”

King co-authored a paper in the International Journal of Obesity on the effects of a 12-week supervised exercise program. Of 34 overweight people, 14 failed to achieve weight loss targets, and King found this was because they had increased cravings for food, particularly energy-rich treats such as donuts and chocolate.

The majority of participants lost weight as expected, and indeed some lost even more. King says he’s not sure whether this was because the exercise acted as an appetite suppressant for them, they were engaging in extra exercise outside the lab, or they made a deliberate decision to reduce their food consumption and were able to stick to it.

Even for those who don’t lose weight from exercising, King says: “People should not be put off exercise. It still has other benefits such as better cardiovascular fitness and lower blood pressure.”

As to what can be done for those who find their exercise efforts undermined by induced cravings, “the first thing is to detect the problem and acknowledge it. Then maybe we can tailor exercise programs to individuals, or maybe add a dietary control.”

Brain Wiring 60% Genetic
A study of identical and non-identical twins has produced an estimate of the contribution of genetics to differences in the efficiency of brain wiring.

“The brain is an extraordinarily complex network of billions of nerve cells interconnected by trillions of fibres,” says Dr Alex Fornito of Melbourne University’s Neuropsychiatry Centre. When one area of the brain needs to communicate with another, the most efficient way is to have a direct connection. However, each connection requires energy to form and maintain.

“The brain tries to maximise its bang-for-buck by striking a balance between making more connections to promote efficient communication and minimising the ‘cost’ or amount of wiring required to make these connections. Our findings indicate that this balance, called ‘cost-efficiency’, has a strong genetic basis,” Fornito says.

By comparing the brains of 38 identical and 26 non-identical twins, Fornito concluded that 60% of the differences between different people could be explained by family genetics.

However, this figure is not consistent across each part of the brain. Efficiency variations in the prefrontal cortex, which is responsible for planning, strategic thinking and decision-making, were 80% genetic, while other areas showed only a weak genetic influence.

Fornito says that other studies have found a relationship between efficient wiring and intelligence, but it would be over-interpreting the results to calculate a genetic influence on intelligence from them. However, he notes that other twin studies suggest that 30–80% of intelligence is genetic, a finding that fits well with his research.

Mapping each of the trillions of fibres in a brain would be a task well beyond modern science but Fornito and colleagues at Cambridge and the University of Queensland used fMRI machines to produce maps of how more than 1000 brain regions communicate with each other to assess the efficiency of the connections. The results were published in The Journal of Neuroscience.

Rainforest Springs from Acidic Waters
While highly acidic conditions are often hostile to life, springs found on Cape York host patches of rainforest that are home to hundreds of species of plants and animals.

The springs sit at the base of a bauxite plateau and drain into the Wenlock River, which boasts the highest diversity of fish species in Australia. As the streams that run from them approach the river they gradually lose their acidity.

The most acidic of the seven known springs has a pH of 3.8, which is less acidic than orange juice but more acidic than tomato juice. Species that have not adapted to the conditions gradually appear along the creek banks.

While it is not unknown for life forms to flourish in apparently hostile conditions, Prof Craig Franklin of the University of Queensland’s School of Biological Sciences says these are the first examples he is aware of where rainforest surrounds such waters. Nevertheless, 16 species of frogs – which are usually sensitive to inhospitable environments – have been found in ponds where the springs rise, along with birds such as the grey goshawk.

Among the 86 plant species identified is the spearwood tree, whose straight trunks were prized by the indigenous population.

When fish or frogs are taken from neutral waters and placed in such acidic conditions their cell membranes and ion pumps are disrupted, causing them to die from a loss of sodium. But Franklin says the inhabitants appear to have evolved pumps that restore their sodium levels.

The springs’ age is unknown, but Franklin says he does not think they have been isolated long enough for new species of vertebrates or plants to evolve. “However, we think we may find new species of invertebrates when we get a chance to do a survey,” he says.

The springs were only found as a result of a survey done in 2006–07 in response to the Australia Zoo’s establishment of the Steve Irwin Reserve in the area. Franklin says the discovery “emphasises the need to do more ground work”. He notes that the area is inaccessible during the wet season.

However, threats have already emerged, with mining proposed for the plateau above the springs. Franklin believes the plateau acts as “a recharge area” and the springs only continue through the dry season as a result of water permeating through the porous bauxite. Bauxite removal would make the springs prone to flood and drought.

Selfish Altruism
An apparent example of animal altruism instead demonstrates selfishness – but selfishness of a very observant and calculating form.

In some species of fairy-wrens, adolescents that are not yet ready to breed assist with the raising of younger siblings (AS, March 2008, p.10). While this does not benefit them as individuals, it increases the chance of their genes prospering. Consequently it poses no problems for evolutionary theory.

However, purple-crowned fairy-wrens go beyond this, with both males and females feeding distantly related nestlings. Careful observation on the part of Dr Anne Peters of Monash University’s School of Biological Sciences has explained this anomaly.

The secret lies in the fact that “good real estate is in short supply” for fairy-wrens. Nest locations are few, and birds are forced to wait before they can breed.

Moreover, the purple-crowned fairy-wrens have a strict queuing system, where the eldest waiting bird inherits the nest when something happens to an incumbent. “We don’t know how they negotiate this,” Peters notes.

In work published in The American Naturalist, Peters found that waiting birds will feed nestlings either if they are siblings or if they are likely to inherit the nest in the near future. It is in the likely inheritor’s best interests to feed the young as this will ensure a plentiful supply of potential young helpers when they become breeders themselves.

“The study showed that the seemingly selfless little helpers are in fact carefully calculating accountants,” Peters says.

The chances of inheritance are particularly high for an older male living near a nest inhabited by a female that is not his mother. Although the wrens will sometimes mate with their parents, they try to avoid this and the offspring do not do well.

Peters says the amount of feeding that helpers do is carefully calibrated against the chance they will inherit the nest soon. Those with little chance of inheriting either disperse and seek other nests, or loaf around “doing as little work as possible” until their prospects improve.

Up to nine birds have been observed helping at one nest, but up to three is common. Helping is largely confined to providing food for nestlings, although Peters says they may play a small role in scaring off predators.

Nestlings of this species get plenty of assistance. While paternal superb fairy-wrens don’t feed their offspring much, preferring to chase other females, Peters says the purple-crowned variety are “almost entirely monogamous”, which she has confirmed with DNA studies. The fathers do as much feeding as the mothers. Most wrens stay near the nest they were born in, and provide assistance there.

The research provides yet more evidence that animal behaviour is based on the survival of one’s genes rather than any altruism. While human acts of apparent altruism are often attributed to a desire for social status, Peters says: “I don’t study people – birds are simpler”.

Peters says it would be hard to test whether birds that are seen to do more helping become role models and gain more assistance for their chicks. “You’d need a much bigger dataset even than we had,” she says.

Glue Clue to Metastasis
A crucial step has been observed in a process where cells “unglue” themselves from one another. The process allows cancers to metastasise, making them more dangerous and harder to treat.

Cells are held together in tissue by proteins such as E-cadherin. “Until recently we mainly thought about the glues,” says Prof Alpha Yap of the University of Queensland’s Institute of Molecular Bioscience. “But in recent years we’ve realised these don’t function on their own – they bind to actin.”

Actin forms a scaffold inside cells. It is linked to E-cadherin by other proteins, including myosin VI.

Yap found that a protein called HGF, which is commonly associated with cancers, separates cadherin and myosin VI. “HGF was causing this interlinked meshwork of proteins to come apart, breaking up the system and causing cells to drift apart,” Yap says. This is associated with a break up of the actin scaffold.

There are times when the body needs cells to move around, particularly during early development, and HGF plays a useful role at these times. However, Yap hopes that if we can understand how to prevent the disruption of myosin VI we may be able to prevent cancers from metastasising, which is “the most devastating and hard to treat phase of the disease”.

The work was published in Current Biology, but to Yap is only the beginning. He suspects that myosin VI is not the only protein affected in pulling cells apart. The same disruptions appear to occur in some non-cancerous diseases, with certain pathogens causing inflammation of epithelia by disrupting junctions between cells, possibly through similar mechanisms.

Honey Fights Antibiotic Resistance
Honey produced by bees feasting on Australian native myrtles has the highest levels of the antibacterial compound methylglyoxal (MGO) known, and have proved potent against antibiotic-resistant superbugs.

Myrtle honey has been marketed for use in antibiotic creams, but it has not attracted the same attention as Manuka honey, which is made from a related New Zealand species. Dr Yasmina Sultanbawa of the Queensland Alliance for Agriculture and Food Innovation says that researchers were surprised to discover up to 1750 mg /kg of MGO in myrtle honey. This encouraged them to test it against methicillin-resistant Staphylococcus aureus (MRSA).

“The sheer strength, due to high levels of active compounds in these honeys, has meant that we have been able to completely inhibit MRSA… with a relatively small quantity of the honey,” Sultanbawa says. “This means potential products could maintain significant levels of antibacterial activity even in surface wounds where the honey is diluted in the bed of the infection.”

Although MGO was used as a measure of the honey’s potency, Sultanbawa says the honey is likely to be more effective than a more concentrated MGO extract produced directly from pollen. “The antibacterial properties are a synergistic effect from MGO but also bee enzymes and other chemicals,” Sultanbawa says. All honeys release hydrogen peroxide, which has antibacterial effects.

Although the species of plant from which the pollen is collected is important for honey’s antibacterial properties, other factors are also involved. “Sometimes you get high levels of MGO from a plant and then another plant nearby will produce much less. We think climate and soil have something to do with it,” Sultanbawa says.

While it might seem surprising that a disease as feared as MRSA can be overcome by something as simple as honey, Sultanbawa says that “myrtle honey has huge potential for emerging pathogens because it is not one single compound, so the microorganism cannot just become resistant to one thing – honey provides a huge range it is difficult for resistance to develop”.

She hopes to put myrtle honey to use against bed sores, diabetic ulcers and chronic wounds that struggle to heal.

Social Media’s Flood Success
Social media played an important part in reducing the human cost of the Queensland floods, according to researchers at the ARC Centre for Excellence for Creative Industries (CCI) and Innovation.

While platforms such as Twitter and Facebook are often derided for the triviality of most of the content they carry, their roles in important events such as the January overthrow of the Tunisian government have been debated.

“Twitter and Facebook were both used extensively throughout the floods – by emergency services such as the Queensland Police, by the Brisbane City Council, by the ABC and by tens of thousands of individual citizens – to warn or to help one another,” says A/Prof Axel Bruns of the CCI.

Bruns says social media offered several advantages in the crisis over more conventional websites. “It’s much easier to follow updates on social media, whereas with websites you have to refresh yourself,” says Bruns. “With social media the police could push the information to you.”

Websites such as the Brisbane City Council could not handle the load during the crisis and went down for periods, while “Twitter and Facebook are designed to withstand a lot of activity,” says Bruns. Moreover, those using smartphones usually already had social media apps that make the sites more easily accessible than an unexplored website.

Bruns tracked the number of tweets using the #qldfloods hashtag and found they peaked at 1200 per hour during the day leading up to the peak of the flood. “As soon as the police saw people using it, they were quick to take it up as a means of disseminating advice more widely and effectively. I’d expect to see a similar pattern in future events.”

Social media can often prove Winston Churchill’s dictum that “a lie can be halfway round the world before the truth has its boots on”. However, Bruns notes that police and emergency services were able to quickly suppress false rumours circulating on social media, such as a report that the Wivenhoe Dam had collapsed. Where once these rumours would have been untraceable to their source, he thinks social media might provide an opportunity for researchers to discover the origin of these stories and investigate what prompted them.

Good Parks Bring Kids Outside
Children whose parents are happy with the quality of parks in their neighbourhood spend less time watching television or playing computer games, according to Dr Jenny Veitch of Deakin University’s Centre for Physical Activity and Nutrition Research.

“Sedentary behaviour is a major contributor to the worldwide childhood obesity epidemic,” says Veitch. Previous research has shown that good parks encourage children to be more active, but Veitch wanted to see if they also raise the total amount of time children spend away from a screen.

“We found that the children who lived near large public open spaces that had a water feature, or lived in a cul-de-sac, and whose parents were more satisfied with the quality of the local parks and playgrounds, spent less time watching TV, using the computer and playing electronic games,” says Veitch. “When we looked at the children’s sedentary behaviours over time we also found that the more satisfied the parents were with the quality of their local public open space in 2004, the less TV the children watched in 2006.”

Veitch has previously demonstrated that older children often will not use playground equipment because it is designed for a younger age group or because efforts to improve safety have made it boring. However, this research did not explore the features that might make some playgrounds or park designs more satisfactory than others.

One oddity in the study was that children with a walking track in their local park had more screen time, apparently because they were less likely to use the park. Veitch admitted the explanation for this was not clear.

“One possible explanation may be that parents perceive that parks with walking paths may have more ‘strangers’ walking through the park and parents may consider this less safe for children.” However, she admitted it might also be that parks with walking paths tend to have some other unattractive feature that had been missed.

Redesigning neighbourhoods to make parks closer and more accessible may be challenging, but Veitch notes: “Fewer than 10% of children are now spending the recommended less than 2 hours a day in front of screens.”

Atomic Lasers Prove Coherent
Physicists at the Australian National University have confirmed a 50-year-old theory about the behaviour of atomic lasers, opening up possibilities for improved analysis of the surfaces of objects.

“Lasers have a property called ‘coherence’,” says Dr Andrew Truscott of the ARC Centre of Excellence for Quantum–Atom Optics. “If you measure the time between the arrivals of the photons in a laser beam, you find that the photons are randomly spaced, with all arrival times between photons equally probable.

“On the other hand, incoherent sources – such as a light bulb – exhibit what is called ‘photon bunching’, where it is more likely that photons arrive within a short space of time of each other,” Truscott says. “This bunching in an incoherent light source is manifested by photons arriving in pairs (what’s known as ‘second order’) or in triplets (‘third order’).”

In the 1960s Roy Glauber, 2005 winner of the Nobel Prize for Physics, predicted that atomic lasers would be coherent at all orders, with no bunching. “Atomic lasers are not new,” says Prof Ken Baldwin, “but we’ve shown that coherence applies up to the third order, and probably at all orders”.

Truscott and Baldwin made a helium laser by cooling helium atoms to the point where they became a Bose–Einstein condensate. The arrival times for atoms from the condensate were measured and proved to be random. When the team warmed the atoms slightly above the condensation point the coherence disappeared, with atoms arriving in pairs and triplets.

Baldwin says coherence means that atomic lasers can be used to make holograms in the same way light lasers are. “You split the laser into two beams and illuminate the object with one beam and interfere with the scattered light with the second beam,” he says.

Atomic lasers will have sensitivity at different scales from light lasers, Baldwin adds. Moreover, lasers made with different atoms should reveal different information.

Squid Polymer Heals Sinuses

Research at the universities of Adelaide and Otago has produced a gel used to prevent post-operative complications from sinus surgery. After successful trials in sheep and humans, US company Medtronic has bought the gel’s patent.

Improbably, the gel is made from chitosan, a polymer extracted from crab shells and squid. Chitosan has also been put to use by Dr Rajiv Padhye of RMIT’s School of Fashion and Textiles to improve the smell of cars by releasing desirable smells only when a seat is occupied.

Otago chemist E/Prof Brian Robinson found a more important use when his son Simon, a surgeon, expressed frustration at the scarring that can block sinus passages after surgery. But now the quid gel is inserted through the nose where it coats surgical wounds, preventing scarring and reducing bleeding.

“From a physician’s point of view, the big thing is that it reduces the amount of bleeding the patient will experience without negative side-effects – it ticks all the boxes,” said Simon Robinson. Half a million sinus operations are performed in America each year, and the father-and-son team hopes it will also prove appropriate in other forms of surgery.

Krill Cam Goes Deep
Krill have been filmed mating half a kilometre beneath the ocean surface. “Up until now it was thought krill only lived and mated in the surface layer of the ocean, from 0–200 metres, but what this video shows is they are also inhabiting and mating in much deeper water,” says Dr So Kawaguchi of the Australian Antarctic Commission.

“After trawling through hours of video we noticed in one segment, filmed at 507 metres, a frenzied twirling of three krill, which turned out to be two males pursing one female,” Kawaguchi said. “The whole mating ritual only lasted 12 seconds and had five distinct phases, which we’ve labelled the ‘chase’, ‘probe’, ‘embrace’, ‘flex’ and ‘push’.” It is the first time the entire process of krill mating has been observed.

Krill are essential to the Antarctic food chain, and an understanding of their breeding may assist sustainable maintenance of southern ocean fisheries. However, the discovery was serendipitous, with research technician Robbie Kilpatrick capturing krill swarming while investigating the effects of long-line fishing on the deep ocean.

Romance Unchanged Online
The process of seeking a relationship online is more similar to traditional dating than might be expected, according to Dr Zoe Hazelwood of Queensland University of Technology’s School of Psychology and Counselling.

“Although online traditional non-verbal cues are not present, in our research we found people do judge potential partners on things aside from what they are saying,” Hazelwood said. “People form impressions online based on things like spelling errors, use of acronyms, amount of exclamation marks, use of grammar – things like that. They may not pursue a relationship with someone if they do not like their writing style, or feel they have poor spelling.”

While online dating profiles have a reputation for wild exaggeration, Hazelwood found “people do stretch the truth about themselves online – but only slightly.” As she points out, making oneself sound more interesting or attractive is hardly new. Relationships begun online also have similar success rates to those based on meeting in other ways.

Stem Cells for Genetic Disease
For the first time in Australia, induced pluripotent stem cells have been produced to fight a specific disease. The disease in question is Friedreich’s ataxia, a rare condition characterised by degeneration of the nerve tissue in the spinal cord.

Dr Alice Pébay and Dr Mirella Dottori of the University of Melbourne took skin biopsies from patients with Friedreich’s ataxia and forced them to become heart and nerve cells. “By focusing on the heart and nerve cell types, we hope to be able to develop treatments to improve heart function and the loss of movement experienced by patients with FA,” Pébay said.

Ufologists Go Troppo
A media release for a UFO convention held in the Northern Territory in March claimed that the site, 360 km north of Alice Springs near the Devil’s Marbles, was chosen because “there have been many UFO sightings recorded in Wycliffe Well, dating back to pre-European settlement.”

The claim is puzzling, as it raises the question of how we know about these sightings. Do Aboriginal cave paintings in the area depict UFOs? Or were the first Europeans in the area greeted by indigenous people keen to tell stories of alien abductions?

While the event seems to have been a marketing exercise for the local holiday park, a much more ambitious international UFO conference planned for October has fallen through. The scale of the cancelled event was so significant that the Northern Territory News published an editorial bemoaning its demise, as well as a vox pop on whether the government should fund the event.

Disaster App
This year’s run of natural disasters may prove a positive for Taiwan’s Lunghwa University of Science and Technology, which has launched the Mobile Savior smartphone application. If there’s a natural disaster, the phone automatically sends a message with the user’s GPS location to emergency contacts, and transforms the screen into a flashlight.

Although the application had been under development for some time, it was launched less than a week after the Japanese earthquake and tsunami.

Bunion No Funion
Bunions may not be fatal, but they are a major contributor to loss of quality of life, according to a La Trobe University study. A/Prof Hylton Menz united with English arthritis researchers to examine the impact of foot deformities on almost 3000 inhabitants of North Staffordshire older than 55. The findings were published in Arthritis Care and Research.

“Our findings indicate that hallux valgus is a significant and disabling musculoskeletal condition that affects overall quality of life,” says Menz. “Interventions to correct or slow the progression of the deformity offer patients beneficial outcomes beyond merely localised pain relief.”

Hallux valgus, popularly known as bunions, were found in 36% of the sample, increasing with age. Women were more likely to suffer than men, presumably because high-heeled or overly narrow shoes are thought to contribute.

Violent Relationships Are Bad For Health
A University of Western Australia study has confirmed a link between mental health and drug addiction among victims of violence at the hands of a partner.

Dr Marika Guggisberg of the university’s School of Population and Health found that women who had suffered physical or sexual violence in a current or former intimate relationship were 24 times more likely to experience mental health issues or abuse alcohol, tobacco or illegal drugs.

Participants were divided into four groups, from those suffering sexual and physical violence to those not suffering any abusive behaviour from a partner. “With remarkable consistency, co-occurring mental health and substance use problems were highest among participants in Group 1,” Guggisberg. “The study concluded that the use of alcohol and other drugs may be a strategy to manage physical and psychological outcomes of the violence.”

Guggisberg said there were important implications for early interventions where women have been subjected to physical, sexual or emotional violence.

A Handle On Life
A simple handle could enable sufferers of rheumatoid arthritis (RA) to safely pick up cooking implements, overcoming a major obstacle to independence.

“It was difficult for sufferers of RA to lift things with their hands due to having limited strength and flexibility,” says Ching-Hao Hsu. “So they had to lift with their forearms. This limited them to using cookware with handles on both sides.

“If a saucepan only had one handle, most people put a towel over their other forearm to grasp the opposite side of the pot, but this was a slippery and dangerous way of lifting, exposing the person to the risk of burns.”

While completing his Bachelor of Design degree at the University of Queensland, Hsu created a universal handle that can grip any piece of kitchenware, while spreading the weight across the user’s forearm.

The arthritis handle has been shortlisted for the Australian Design Awards, along with almost 30 entries including a portable wine bar and a screen enabling wind turbines to generate power at lower ambient wind speeds.