Do Lipid Rafts Exist?

The contention that molecular platforms known as lipid rails sail on the cell's outer, or plasma. membrane has kept researchers debating for more than a decade. Although many scientists argue that rafts either don't exist or have no biological relevance, their supporters insist the idea remains afloat. Cell biologist Kai Simons. now at the Max Planck Institute of Molecular Cell Biology and Genetics in Dresden, Germany. and his colleague Dina lkonen christened the term "lipid raft" in a I 997 Nature paper that detailed the concept. At the time, the main model of the plasma membrane portrayed it as a sea of lipids through which proteins drifted...

Read more »

To Self-Diagnose, Spit On iPhone

Handheld gadgets could one day diagnose infections at the push of a button by using the supersensitive touchscreens in today's smartphones. Many believe that in the future collecting samples of saliva, urine or blood could be performed using a cheap, USB-stick-sized throwaway device called a lab-on-a-chip. The user would inject a droplet of the fluid in the chip, and micropumps inside it would send the fluid to internal vessels containing reagents that extract target disease biomarker molecules. The whole device would then be sent to a lab for analysis. But Hyun Gyu Park and Byoung Yeon Won at the Korea Advanced  Institute for Science and Technology in Daejeon think touchscreens could improve the process by letting your phone replace the lab work. Park suggests the lab-on-a-chip could...

Read more »

Extreme Weather, Time To Prepare

An international scientific assessment finds for the first time that human activity has indeed driven not just global warming but also increases in some extreme weather and climate events around the world in recent decades. And those and likely other weather extremes will worsen in coming decades as greenhouse gases mount, the report finds. But uncertainties are rife in the still-emerging field of extreme events. Scientists cannot attribute a particular drought or flood to global warming, and they can say little about past or future trends in the risk of high-profile hazards such as tropical cyclones. Damage from weather disasters has been climbing,...

Read more »

Sauna's Boost For Heart and Homour

That warm, fuzzy feeling you get from sitting in a sauna isn't in your imagination — and it may also help your heart. People with chronic heart failure who took saunas five times a week for three weeks improved their heart function and the amount of exercise they could do. Meanwhile, neurons that release the "happiness molecule" serotonin respond to increases in body temperature, perhaps explaining the sauna's pleasurable effects. Heart failure occurs when the heart is unable to supply enough blood to the body, resulting in shortness of breath and difficulty exercising. Previous studies have hinted that saunas might boost health. To investigate,...

Read more »

Alzheimer’s Damage Reserved With A Jolt

Brain shrinkage in people with Alzheimer's disease can be reversed in some cases - by jolting the degenerating tissue with electrical impulses. Moreover, doing so reduces the cognitive decline associated with the disease. "In Alzheimer's disease it is known that the brain shrinks, particularly the hippocampus," says Andres Lozano at Toronto Western Hospital in Ontario, Canada. What's more, brain scans show that the temporal lobe, which contains the hippocampus, and another region called the posterior cingulate use less glucose than normal, suggesting they have shut down. Both regions play an important role in memory. To try to reverse these...

Read more »

Humanity’s First Word? Duh!

You may think humanity's first words are lost in the noise of ancient history, but an unlikely experiment using plastic tubes and puffs of air is helping to recreate the first sounds uttered by our distant ancestors. Many animals communicate with sounds, but it is the variety of our language that sets us apart. Over millions of years, changes to our vocal organs have allowed us to produce a rich mix of sounds. One such change was the loss of the air sac — a balloon-like organ that helps primates to produce booming noises. All primates have an air sac except humans, in whom it has shrunk to a vestigial organ. Palaeontologists can date when our ancestors lost the organ, as the tissue attaches to a skeletal feature called the hyoid bulla, which is absent in humans. "Lucy's baby", an Australopithecus...

Read more »

Our Ancestor, The Mega-Organism

ONCE upon a time, 3 billion years ago, there lived a single organism called LUCA. It was enormous: a mega-organism like none seen since, it filled the planet's oceans before splitting into three and giving birth to the ancestors of all living things on Earth today. This strange picture is emerging from efforts to pin down the last universal common ancestor — not the first life that emerged on Earth but the life form that gave rise to all others. The latest results suggest LUCA was the result of early life's fight to survive, attempts at which turned the ocean into a global genetic swap shop for hundreds of millions of years. Cells struggling...

Read more »

A Collection Of Nothings Means Everything To Mathematics

THE mathematicians' version of nothing is the empty set. This is a collection that doesn't actually contain anything, such as my own collection of vintage Rolls-Royces. The empty set may seem a bit feeble, but appearances deceive; it provides a vital building block for the whole of mathematics. It all started in the late 1800s. While most mathematicians were busy adding a nice piece of furniture, a new room, even an entire storey to the growing mathematical edifice, a group of worrywarts started to fret about the cellar. Innovations like non-Euclidean geometry and Fourier analysis were all very well - but were the underpinnings sound? To prove...

Read more »

A Burger Every Few Days To Keep Climate Change At Bay

Meat is bad: bad for you, bad for the environment. At least that's the usual argument. Each year, the doors to the UN climate negotiations, which kick off again in Durban, South Africa, on 28 November, are assailed by demonstrators brandishing pro-vegetarian placards. The fact is that livestock farming accounts for a whopping 15 per cent of all greenhouse gas emissions. We can't all go veggie, so just how much meat is it OK for an eco-citizen to eat?It's not just the demonstrators who are concerned about food's impact on the climate. This week, a major report concludes that food production is too close to the limits of a "safe operating  space" defined by how much we need, how much we can produce, and its impact on the climate.Meat is a major contributor to that: 80 per cent of agricultural...

Read more »

Hothouse Earth Is On The Horizon

An era of ice that has gripped Earth's poles for 35 million years could come to an end as extreme global warming really begins to bite. Previously unknown sources of positive feedback — including "hyperwarming" that was last seen on Earth half a billion years ago— may push global temperatures high enough to send Earth into a hothouse state with tropical forests growing close to the poles. Climate scientists typically limit themselves to the 21st century when predicting how human activity will affect global temperatures. The latest predictions are bolder, though: the first systematic forecasts through to 2300 are beginning to arrive. They follow...

Read more »

See Beyond The Light To Find Future Disease

DEEP in the heart of the cell, your DNA may be undergoing subtle changes that could lead to a devastating disease several years down the line. New microscopy techniques are now lifting the lid on this inner world, potentially offering an early-warning system for cancer or Alzheirner's long before the diseases begin to bite. Full-blown disease may be preceded by a long build-up. For example, a change in chromatin — the complex of DNA and proteins that packages DNA into the cell nucleus— is one of the earliest events to occur after exposure to carcinogens or ultraviolet rays. Changes sometimes happen years before symptoms of a tumour manifest themselves. However,...

Read more »

Brain Doping

MOST of us want to reach our full potential. We might drink a cup of coffee to stay alert, or go for a run to feel on top of the job. So where's the harm in taking a pill that can do the same thing? So-called cognitive-enhancing drugs are usually prescribed to treat medical conditions, but they are also known for their ability to improve memory or focus. Many people buy them over the internet, which is risky because they don't know what they are getting. We also know next to nothing about their long-term effects on the brains of healthy people, particularly the young. But some scientists believe they could have a beneficial role to play in society,...

Read more »

Liquid Power For Chips

GETTING microchips wet is normally best avoided. But a new type of chip that is both powered and cooled by fluid pumping through it could power the computers, srnartphones and tablets of the future. If the design is successful, its inventors at IBM argue an entire supercomputer—like Watson, the firm's natural-language-processing trivia savant— could one day be squeezed onto mobile devices small enough to fit in your pocket. The idea is inspired by the way the human brain is powered, says Bruno Michel, who is leading the work at IBM's Zurich Research Laboratory in Switzerland. "The human brain is 10,000 times more dense and efficient than any computer today. That's possible because it uses only one, extremely efficient, network of capillaries and blood vessels to transport heat and energy,...

Read more »

Ethical and Plentiful Stem Cells From Milk

Embryonic-like stein cells have been discovered in breast milk in large numbers. This is the first time such cells have been found in an adult. If the cells live up to their potential we may soon have stem cells for medical therapy, without destroying any embryos. Back in 2008, Peter Hartrnann at the University of Western Australia in Crawley and his colleagues announced they had discovered stem cells in breast milk. Crucially, these cells have now been turned into the kind that represent all three embryonic germ layers —the endoderm, mesoderm and  ectoderm — a defining property of embryonic stem cells (ESCs). "They can become bone cells, joint cells, pancreatic cells that produce their own insulin, liver cells that produce albumin, and neuronal cells," says Foteini Hassiotou of Hartmann's...

Read more »

Pull Out Photons From Empty Space

You can get something from nothing — as long as you are moving close to the speed of light. The discovery confirms a 41-year-old prediction on how to pull energy from empty space and produce light. The phenomenon relies on the long-established fact that empty space is not at all empty, but fizzing with particles that pop in and out of existence. This is down to the laws of quantum mechanics, which say that even a vaccum cannot have exactly zero energy but must exhibit small fluctuations of energy. These fluctuations show themselves as pairs of short-lived particles.The presence of these "virtual" particles, usually photons, has long been proved in experiments demonstrating the standard Casimir effect, in which two parallel mirrors set close together I' will feel a pull towards each other....

Read more »

Malaria's Nemesis

FORTY years ago a secret military project In communist China yielded one of the greatest drug discoveries in modern medicine. Artemisinin remains the most effective treatment for malaria today and has saved millions of lives. Until recently, though, the drug's origins were a mystery."I was at a meeting in Shanghai in 2005 with all of the Chinese inalariologists and tasked who discovered artemisinin," says Louis Miller, a malaria researcher at the US National Institutes of Health in Rockville, Maryland. "I was shocked that no one knew." Miller and his NIH colleage Xinzhuan Su began digging into the drug's history. After reviewing letters, researchers' original notebooks and transcripts from once-secret meetings, they concluded the major credit should go to pharmacologist Tu Youyou. Two months...

Read more »

Why Isn't NASA Hunting For Life?

Even the most ardent fans of the Red Planet must occasionally wish for more than just hints of water popping up in ever-new places. So why not send a robot to hunt directly for little green men? One word: Viking. NASA's Viking landers did just that in 1976, laying out a tasty solution of nutrients to attract any microbes that might be living in a soil sample, like cookies left on a plate for Santa. The nutrients were laced with radioactive carbon, so if the solution was digested, a radiation monitor above the sample would detect the resulting gas. Intriguingly, radioactive carbon was detected, but then another experiment found no evidence of organic compounds in the soil - there were no alien bodies. "They were hoping to find signs of life but the results came back basically negative - there...

Read more »

Science Now Makes It Possible To Attribute Some Types Of Weather Event To Climate Change

In the aftermath of hurricane Katrina in 2005, a vigorous debate raged as to whether it was a "normal " natural disaster or a consequence of global warming. Al Gore depicted the devastation of New Orleans in his movie An Inconvenient Truth and linked it to climate change. I became involved during a case before the High Court in London challenging a UK government decision to distribute the movie to schools. I was asked to provide expert written evidence on the extent to which the film correctly represented scientific understanding at the time.I liked the film and thought that Gore's presentation of the causes and likely effects of climate change was broadly accurate. As the Intergovernmental Panel on Climate Change (IPCC) concluded in its most recent assessment report: "warming of the climate...

Read more »