Tech Universe: Monday 4 July

UNDERWATER EARS: Researchers at Stanford University used the sensitive hearing of Orcas as their inspiration for a very sensitive underwater microphone. The microphones include three diaphragms of different sizes to capture the range of sounds. Each diaphragm is a membrane about 500 nanometres thick with nano-holes to allow water through. A fibre optic cable shines light onto the diaphragm and the nature of the reflected light indicates sounds. The microphone has a sensitivity range of 160 decibels and can function at any depth. Except Orcas do it without fibreoptics, I presume. More details at Wired

RED LIGHT: University of Toronto engineers have created solar cells that capture a broad range of light waves that may in theory reach up to 42% efficiency. They use colloidal quantum dots to link a layer that harvests visible light with one that collects infrared to capture the sun's most energetic photons. Then we need to get real world efficiency up to the same level. More information here .

Breathing Exercises Should Be One of Your Tools in Completely ...

Until recently, western medical research has been inconclusive in determining whether or not there is real benefit for an asthmatic to conduct breathing exercises as part of an overall asthma management program. These exercises have certainly been popular in many alternative type asthma management programs but have not yet been embraced by allopathic, or traditional western physicians.

But they are beneficial and will help an asthma sufferer reduce symptoms and increase strength.

The two most often practiced techniques are Buteyko (named after the Russian doctor who developed them) and a yoga training technique known as pranayama. In very simple terms, Buteyko exercises involve breathing through the nose (not mouth), exhaling for as long as possible and then holding the breath as long as possible at the end of the exhale. During the inhale, a series of short, but shallow breaths are practiced. Pranayama is about correct posture, relaxation and controlled, slow inhalation and exhalation, with a focus on using the diaphragm muscles to assist with breathing.

While breathing techniques have long been supported by naturopathic physicians, it is only in the last several years that the allopathic medical community (traditional doctors) has moved to try and quantify any potential benefit from these exercises. One study, published in the March 2004 edition of “Current Opinion in Pulmonary Medicine” concluded there might be some benefit, although more study was required.

In several patient groups (some using buteyko training and others using pranayana), there did appear to be reduced asthma symptoms although lung function did not appreciably change (as measured by PEFR). Nevertheless, patients felt better and did experience a reduction in need for relief medications.

How do breathing exercises help asthmatics

Since asthma is related to inflammation of the lungs and constriction of the smooth involuntary bronchiole muscles, how can doing breathing exercises help alleviate symptoms?

For starters, it is estimated that some 30% of asthmatics suffer some degree of breathing dysfunction. Bad habits are easily learned when suffering from asthma symptoms and it is not uncommon for those habits to continue in between attacks – breathing through the mouth and short, shallow breaths for example.

This type of breathing deprives the lungs of their full potential to effectively exchange oxygen with carbon dioxide. Breathing exercises enforce good habits where the full range of lung function is used. Consequently, the body gets the oxygen it needs and the chronic asthmatic feels better, with more energy.

The function of the diaphragm

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