Experts have invented a way for audiophiles to listen to music over loudspeakers that don’t annoy people standing nearby.
“You may soon be able to enjoy audio without those uncomfortable earphones or headsets and not bother your neighbors,“ said researcher Chan-Hui Lee at the Korea Advanced Institute of Science and Technology.
The “personal sound system “ that Lee and his colleagues envision focuses sound waves from several loudspeakers onto a listening zone. Outside this zone, the sound waves would be much less audible, LiveScience.com said.
The researchers devised a simple prototype involving half-inch speakers, nine of which were arranged in a row 13 inches (33 centimeters) long. They found there was a 20-decibel or more difference in sound intensity between the listening zone and outside it--the difference between, say, a normal conversation and a whisper.
Lee and his colleagues suggest personal sound systems could find use with laptops and televisions.
“But the ultimate goal are mobile phones and PDA systems,“ Lee told LiveScience.
To fit personal sound systems on portable devices such as mobile phones, obviously smaller speakers are needed.
Unfortunately, such speakers generally do not broadcast the wide range of audio frequencies personal sound systems need. “The research there is ongoing,“ Lee said.
If such portable systems are ever devised, people might listen in, say, by holding players in front of them, although the exact design still needs to be worked out, Lee added.

Scientists may be a step closer to uncovering the cause of certain types of debilitating migraine headaches.
A French team observed activation in the hypothalamus region of the brain as sufferers had a migraine attack, BBC reported.
The hypothalamus has long been suspected as it regulates physiological responses to factors known to trigger headaches, such as hunger.
It is hoped the discovery, featured in the journal Headache, could lead to new treatments.
The researchers, from Rangueil Hospital, used a technique called Positron Emission Tomography (PET), which contrasts functional activity within the brain, on seven patients with migraine without aura, the most common type of migraine.
Previously, activation in the brain stem and midbrain, and a thickening in some areas of the cortex were seen in migraine sufferers.
The present study may have seen a more detailed pathogenesis of the condition for two reasons.
First, timing was crucial: to capture an attack as it happened, patients rushed to hospital without self-medicating, arriving on average around three hours after the onset of the migraine.
Second, the observed headaches were spontaneous, and not chemically induced as in other laboratory studies.
Lead researcher Dr Marie Denuelle said, “When you induce the attack you miss the hypothalamic activation.
“We suspect the hypothalamus may play a role in the start of the migraine attack.
“But to prove it we would need to do similar study before the start of an attack.“
Dr Andrew Dowson, director of headache services at Kings College Hospital, London, said, “It has been suggested for many years that the hypothalamus is involved in the early stages of migraine attacks.
“But there are other factors involved in the early generation of headache.“
Activation of the hypothalamus had previously only been seen in cluster headache, a different and altogether more crippling condition.
Cluster headache sufferers experience headaches on a regular basis: for certain months of the year in the episodic form, or every day at regular intervals in the chronic form.
So debilitating can the attacks be that they have been dubbed “suicide headaches“ because some sufferers have taken their own lives.
The new evidence for hypothalamic activation in migraine may explain why some migraine drugs, particularly the triptans, can sometimes be effective at aborting a cluster headache attack.

Coffee and tea may increase the body's sensitivity to the blood-sugar-regulating hormone insulin.

Coffee and tea lovers may have a slightly reduced risk of developing kidney cancer, research hints. The findings, based on an analysis of 13 previous studies, suggest that coffee and tea may be protective against kidney cancer, while milk, soda and juice seem to have no effect one way or the other, Reuters reported.
Across the studies, people who drank three or more cups of coffee a day were 16 percent less likely to develop kidney cancer than those who averaged less than a cup per day. And those who sipped just one 8-ounce cup of tea each day had a 15 percent lower risk of the disease than non-drinkers.
The findings appear in the International Journal of Cancer.
While the study cannot show that coffee or tea directly lower kidney cancer risk, there are reasons why the beverages could be beneficial, according to the researchers, led by Dr. Jung Eun Lee of Harvard Medical School in Boston.
For example, they explain, coffee and tea may increase the body’s sensitivity to the blood-sugar-regulating hormone insulin, and researchers suspect that insulin levels over time may affect kidney cancer risk.
Coffee and tea also contain antioxidant compounds that may help protect cells in the kidney from cancer-promoting damage, the researchers point out.
For their study, the investigators combined the results of 13 long-term studies that included a total of 530,469 women and 244,483 men. Each study collected information on participants’ diets at the outset and then followed them for seven to 20 years.
Coffee and tea consumption were linked to a lower risk of kidney cancer even when the researchers accounted for a number of factors known to affect people’s risk of the disease--such as obesity, smoking and high blood pressure.
“Our results suggest that coffee and tea consumption may be associated with a modestly lower risk of (kidney) cancer, whereas intakes of milk, juice and soda were not associated with risk,“ Lee’s team writes.
They say more studies are needed to understand why coffee and tea might be protective against the disease.

A Swiss company called Rinspeed has recently announced its newest project: an underwater car. Named ’sQuba,’ the car can both drive on roads, and then--at the push of a button--dive up to 10 meters (33 feet) under the sea.
Rinspeed describes sQuba as the world’s first real car to drive both on land and underwater, thanks to some cutting-edge technology. The car has a steel chassis, while its lightweight body panels are made of carbon nanotubes, Physorg.com wrote.
An electric motor provides rear-wheel drive while on roads. Underwater, two propellers in the stern and two jet drives in the bow propel the amphibious vehicle. With zero emissions, the design is even environmentally friendly, eliminating any pollution into the sea.
The two-seater also includes a self-contained on-board oxygen system to supply the driver and passenger with fresh air for breathing.
Rinspeed CEO Frank Rinderknecht admits that part of the inspiration for the underwater car comes from the 1977 James Bond hit “The Spy Who Loved Me.“
The sQuba concept symbolizes the realization of this fantasy that once sparked his imagination.
“And exactly thirty years later this amazing--yet at the time animated--film sequence materializes and becomes reality, in today’s world,“ said Rinderknecht.
The sQuba car will be presented at the Geneva Motor Show, which runs from March 6-16, 2008. However, mass-production of the car is not planned for the foreseeable future.

Venoms from different snake families may have many deadly ingredients in common, more than was previously thought.
A study published in the online open access journal BMC Molecular Biology has unexpectedly discovered three-finger toxins in a subspecies of the Massasauga Rattlesnake, as well as evidence for a novel toxin genes resulting from gene fusion, ScienceDaily reported.
Susanta Pahari from National University of Singapore, Singapore (currently working at Sri Bhagawan Mahaveer Jain College, Bangalore, India) used venom glands from a rare rattlesnake that lives in arid and desert grasslands.
Known as Desert Massasauga (Sistrurus catenatus edwardsii), this pitviper is a subspecies of the North American Massasauga Rattlesnake (Sistrurus catenatus).
Together with Stephen Mackessy from the University of Northern Colorado, USA and R. Manjunatha Kini from National University of Singapore, Singapore, Pahari constructed a cDNA library of the snake’s venom gland and created 576 tagged sequences.
A cocktail of recognized venom toxin sequences was detected in the library, but the venom also contained three-finger toxin-like transcripts, a family of poisons thought only to occur in another family of snakes (Elapidae).
The team also spotted a novel toxin-like transcript generated by the fusion of two individual toxin genes, a mechanism not previously observed in toxin evolution.
Toxin diversity is usually the result of gene duplication and subsequently neofunctionalization is achieved through several point mutations (called accelerated evolution) on the surface of the protein.
Pahari says “In addition to gene duplication, exon shuffling or transcriptional splicing may also contribute to generating the diversity of toxins and toxin isoforms observed among snake venoms.“
Previously, researchers identified venom compounds using protein chemistry or individual gene cloning methods. However, less abundant toxins were often missed.
The library method has now revealed new toxin genes and even new families of toxins. Taking low abundance toxins into consideration shows advanced snakes’ venoms actually have a greater similarity than previously recognized.
Snake venoms are complex mixtures of pharmacologically active proteins and peptides. Treating snake venom victims can be complicated because of the variation between venoms even within snake families.