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How Early Can We Predict and Prevent Psychosis?

There is growing evidence that subtle changes in brain function can be identified long before the onset of psychotic symptoms. Credit: vchalup/Adobe

There is growing evidence that subtle changes in brain function can be identified long before the onset of psychotic symptoms. Credit: vchalup/Adobe

By Scott R. Clark, K. Oliver Schubert & Bernhard T. Baune

The addition of a simple blood test could improve predictions of a first psychotic episode.

Psychosis is a loss of contact with reality that manifests in abnormal perception, thinking and behaviour. These abnormalities can include hallucinations (e.g. hearing non-existent derogatory voices), delusions (e.g. of government surveillance and persecution), disorganised movement, poor motivation, slowed thinking, and loss of expression of emotions.

Off the Grid

dmfoto12/Adobe

Credit: dmfoto12/Adobe

By Cameron Shearer

Australians have taken to solar energy, but much of the electricity they generate cannot be stored and is returned back to the grid. However, commercial residential battery systems are now available, with new technologies on the horizon.

An increasing number of Australian households now produce their own electricity through rooftop solar panels. During a typical day, the electricity generated will be used to run some appliances, and any power left over is returned to the electricity grid with the homeowner receiving a feed-in tariff for the electricity they return. The plan of the homeowner is for the initial cost of the solar panel installation to be slowly paid back through lower power bills and feed-in tariffs.

The Other Red Meat on the “Real” Palaeodiet

Rama/CC BY-SA 2.0 fr

Reconstruction of a Mesolithic (late hunter-gatherer) tomb from France. It shows two women in their twenties or early thirties, both with traumatic injuries to the skull. One is believed to have been buried while still alive. Rama/CC BY-SA 2.0 fr

By Darren Curnoe

Are we really willing to eat the authentic palaeodiet, even if it means taking up cannibalism?

The so-called palaeodiet (and now even the palaeo-epigenetic diet) has come under a lot of scrutiny of late for making wild and unsubstantiated claims and for being downright dangerous to our health.

If we’re serious about the palaeolifestyle, then just how far are we prepared to take this obsession with our Stone Age heritage and its claimed benefits? If it really offers a panacea for good health, shouldn’t we all become cave-dwellers again and consume the full variety of foods our ancestors actually ate?

Can Hookworms Cure Coeliac Disease?

Can Hookworms Cure Coeliac Disease?

By Paul Giacomin

Coeliac disease patients infected with hookworms can tolerate gluten-containing foods, revealing the potential for these parasites and their secretions to treat a range of inflammatory diseases.

People have co-existed with parasites throughout history. To enable their survival, the parasites evolved sophisticated strategies to avoid attack by their human host’s immune system.

Conditions for Creation

A deep-sea volcanic eruption at Brimstone Pit, a vent on the side of a large submarine volcano in the Mariana Arc – part of the “Submarine Ring of Fire” that circles the Pacific Ocean basin, where tectonic plates spread or collide. Credit: NOAA Submarine Ring of Fire 2006 (Volcanoes Unit MTMNM)

A deep-sea volcanic eruption at Brimstone Pit, a vent on the side of a large submarine volcano in the Mariana Arc – part of the “Submarine Ring of Fire” that circles the Pacific Ocean basin, where tectonic plates spread or collide. Credit: NOAA Submarine Ring of Fire 2006 (Volcanoes Unit MTMNM)

By Simon Turner, Tracy Rushmer, Mark Reagan & Jean-Francois Moyen

A sequence of the world’s oldest rocks in the depths of the Mariana Trench indicates that both plate tectonics and life may have commenced on Earth 4.4 billion years ago.

Plate tectonics is the process by which large parts of Earth’s outer plates slide past each other. This process of subduction causes the natural disasters we are all familiar with: earthquakes and volcanic eruptions. Subduction also created the continental crust upon which we live and cultivated a life-friendly environment for the Earth.

Survival of the Different

When a simple ancestral population of bacteria is kept in a constant controlled environment, a rich mixture of types evolves rather than a single “winner”.

When a simple ancestral population of bacteria is kept in a constant controlled environment, a rich mixture of types evolves rather than a single “winner”.

By Tom Ferenci

If evolution is about survival of the fittest, why does diversity emerge instead of perfectly evolved organisms that are fit in all environments? Now the complex trade-offs that shape the evolution of diversity have been measured.

Darwin told us that evolution is about the natural selection of types best fitted to their environment. This is sometimes interpreted as the survival of the fittest, but this is not really true. The emergence of super-fit types is strongly constrained by complex evolutionary forces we do not fully understand. Rather than leading to outright winners, diversity is the most common outcome of evolution.

Islands of Extinction

The flooding of Chiew Larn Reservoir

The flooding of Chiew Larn Reservoir created scores of small islands like the one in the foreground. Photo: Tony Lynam

By William Laurance

Native mammals are disappearing rapidly as an aggressive invader takes over in forests fragmented by a hydroelectric dam.

Take a glance around you right now and chances are that any native vegetation you see will be in small, isolated patches of what was formerly an expanse of natural habitat. This, of course, is the process of habitat fragmentation, one of the most devastating ways that humans are transforming the Earth.

Why Don’t Mozzies Get a Fever?

mosquito

Viral diseases transmitted by mosquito bite are a major public health problem worldwide.

By Prasad Paradkar, Jean-Bernard Duchemin & Peter Walker

Understanding how mosquitoes protect themselves from the viruses they carry could lead to new ways of controlling the spread of viral diseases like dengue or yellow fever.

Why are some mosquitoes so effective in transmitting disease-causing viruses such as dengue, yellow fever and West Nile? And why do other mosquitoes transmit viruses poorly? Why do viruses that cause devastating diseases in humans and animals cause no disease in the mosquitoes that carry them?

Crystals So Flexible They Can Be Tied in a Knot

Credit: Leigh Prather

Credit: Leigh Prather

By John McMurtrie & Jack Clegg

The ordered structure of most crystals makes them brittle and inflexible, but the discovery of crystals with elastic properties opens a range of new uses in emerging technologies.

Crystals are beautiful objects. They have been admired for millennia because of their intriguing properties, and in many cultures are thought to be imbued with magical properties. Crystals, do however, underpin a wide variety of modern technologies, including semi-conductors and lasers, which are used in everything from mobile phones to space-shuttles.

A Quantum of Silence

Credit: Anterovium/Adobe

Credit: Anterovium/Adobe

By Luke Helt & Michael Steel

Single photons have weird yet useful behaviours, with applications ranging from secure communications to quantum computing. While current silicon photon sources often produce additional “noise photons” that interfere with these emerging technologies, new research has discovered a method to quieten this quantum chaos.

Not all light is the same. For example, a light bulb emits countless numbers of light particles, or photons, in all directions at any given moment, making it useful for lighting a room. In contrast, laser light emits controllable numbers of photons in controllable directions, enabling it to weld metal, read DVDs or perform eye surgery.