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A Catalyst for Life

Credit: agsandrew/iStockphoto

Credit: agsandrew/iStockphoto

By Rowena Ball

A chemical found in hair bleach may have catalysed life, and can even explain why new life is no longer being created from non-living building blocks on modern Earth.

On the prebiotic Earth more than 3.6 billion years ago there were no living cells and no proteins. Instead it is thought that life began with RNA molecules replicating in rock pores around hydrothermal vents prior to the evolution of DNA, cell membranes and proteins. This is the “RNA World” hypothesis.

How Certain Can You Be?

atom

The Heisenberg Uncertainty Principle is one of the central features of quantum mechanics, but it has been misunderstood for a long time. Only now – almost a century later – has a first complete quantitative description of his uncertainty principle been found.

By Martin Ringbauer

A team of physicists has challenged the limits of Heisenberg’s famous uncertainty principle by measuring quantum particles with unprecedented accuracy.

At the heart of all the natural sciences is measurement – assigning a number to a physical property. Just how accurately we can measure, however, has long been an open question. Can we just keep building better and better devices to make more and more accurate measurements?

A Fine Balance for Dementia Drugs

The transparent nature of the roundworm Caenorhabditis elegans makes it easy for scientists to study its cells. Credit: HoPo/Wikimedia Commons

The transparent nature of the roundworm Caenorhabditis elegans makes it easy for scientists to study its cells. Credit: HoPo/Wikimedia Commons

By Yee Lian Chew & Hannah Nicholas

Since too much or too little of a key protein expressed in the brain can accelerate brain ageing, drugs developed to regulate its levels face a fine balancing act.

Diseases of the ageing brain, such as Alzheimer's disease, are becoming increasingly common but the causes of these conditions are relatively unknown. We have studied brain ageing in a small transparent roundworm, and found that accelerated ageing stemmed from either too low or too high levels of a protein called tau. We think that a similar thing may be happening in people, so our findings could improve our understanding of what causes Alzheimer's disease.

Out of the Darkness

Out of the Darkness

By Mandy Thoo

Researchers find that light therapy and saffron can protect us against the leading stealers of sight.

As we live longer our eyesight fails, leaving many of us helpless in the dark for years towards the end of our lives. In the fight against sight-stealers, scientists at the ARC Centre of Excellence in Vision Science are opening new fronts: fast, accurate and painless eye tests, slowing the advance of damaging eye diseases, and pioneering techniques that may one day actually reverse the loss of sight.

Are Fad Diets Worth Their Weight?

Fad diet

Fad diets often encourage short-term changes in eating behaviour rather than encouraging healthy changes that can be sustained.

By Tim Crowe

Fad diets continue to attract public attention with their promises of quick and easy weight loss, but the truth is that these diets are just a large serving size of smoke and mirrors.

How many times have you read and heard that diets don’t work? Yet this one simple statement has stood the test of time. At any time, a large proportion of the population is on some form of diet, yet waistlines are still expanding.

With new fad diets emerging all the time, it is time to tackle just what makes a diet a “fad”, examine the downsides to jumping on the latest bandwagon and finally ask: if fad diets don’t work, what does?

How to Spot a Fad Diet

Why the Long Face?

Photo: Guy Nolch

Head shape is a good indicator of the predator’s tendency to feed on either small or large prey. Photo: Guy Nolch

By Christopher Walmsley & Colin McHenry

The jaw strength of crocodiles can be predicted by simple linear measurements that could provide new insights into the diets of extinct marine reptiles.

Crocodiles and their relatives have been on the planet for around 200 million years, and today are the largest of all living reptiles. They are found in many countries all over the globe, preferring to inhabit warm waters in regions like Africa, South-East Asia and Australia. This iconic predator has stood the evolutionary test of time, managing to live and even thrive in environments where many others failed.

Thief of Time

A bee with a miniaturised transponder attached to its thorax

A bee with a miniaturised transponder attached to its thorax to enable monitoring of its flight after anaesthesia.

By Guy Warman, Craig Millar & James Cheeseman

General anaesthesia alters our perception of time by shifting the expression of clock genes to a new time zone, leading to chemically induced jet lag.

Despite the astonishing fact that 234 million general anaesthetics are administered each year around the world, the way in which anaesthetics put you to sleep remains unknown. The phrase “put you to sleep” is synonymous with general anaesthesia, and recent evidence suggests this metaphor may be more accurate than we had ever imagined. At least some anaesthetics appear to act in part by hijacking sleep-promoting pathways in the brain to exert their effects.

Guy Warman is a senior lecturer and James Cheeseman a lecturer in the Department of Anaesthesiology at the University of Auckland. Craig Millar is a senior lecturer in the School of Biological Sciences at the University of Auckland. Eva Winnebeck, Randolf Menzel and Jamie Sleigh were major contributors and authors of this research, which was funded by a Marsden Grant from the Royal Society of New Zealand and by the University of Auckland, and published in Proceeedings of the National Academy of Sciences.

A Walk Through the Valley of Cell Death

Dr David Vaux

Dr David Vaux

By Barry Leviny

After three decades, David Vaux’s initial research into apoptosis has led to clinical trials of a potential treatment for leukaemia.

Many of us, if we’re honest, would like to help find a cure for cancer, or at least a form of it. I’ve recently been talking to someone who may have done just that. It was a long, complicated road and I was keen to hear how he did it.

The Curious Story of the Human Backside

Credit: Wikimedia Commons

The human backside has been celebrated in art for its beauty and as a sign of fertility in women for centuries, as shown by this painting entitled Love Whispers by the 19th century German painter Heinrich Lossow. Credit: Wikimedia Commons

By Darren Curnoe

The human posterior is rather peculiar compared with the backsides of our close primate cousins. Its unusual form tells the story of our evolution like no other part of the human body.

Volcanoes Sheltered Life through Ice Ages

Mount Erebus is perhaps the most well-known volcano in Antarctica, and is one of the large volcanoes that may have sheltered life through past ice ages. Photo: Steven Chown

Mount Erebus is perhaps the most well-known volcano in Antarctica, and is one of the large volcanoes that may have sheltered life through past ice ages. Photo: Steven Chown

By Ceridwen Fraser

Researchers studying the diversity of life in Antarctica have found surprising evidence that many plants and animals survived past ice ages by huddling close to warm volcanoes.

As the Earth enters an ice age and the polar ice caps expand, many plants and animals move away from the poles towards the Equator. Then, as the world warms and the polar ice caps shrink, species move back towards the poles.

Increasingly, however, we’re seeing evidence from genetics and fossil pollen that many species must actually have survived within the ice-covered regions around the Arctic and Antarctic. How could species that need ice-free land to live manage to survive within regions covered by massive glaciers?

Do Hot Rocks Make Ice-Free Oases?