Sci-tech: The wondrous world of science
Hope for the blind
Neuroscientists at the Wisconsin-based Wicab, Inc. have developed a device “BrainPort” that helps users see without their eyes. According to the late co-founder of the company, the neuroscientist Paul Bach-y-Rita, we see with our brains and not with our eyes, so that it should be possible to develop devices that allow the blind to see.
The device involves collecting visual data using a small digital camera that the blind person wears on sunglasses. The digital optical signals are then converted by a central processing unit (CPU) about the size of a cell phone that the blind person carries in his/her pocket into electrical signals, simulating and replacing the function of the retina (normal human beings use about two million optic nerves to transmit the optical images from the retina in the form of electrical signals to the brain). The CPU then sends the signals to an electrode array on the surface of a lollipop-like device that the blind person carries in the mouth.
The bunch of nerves on the tongue receive these signals and transmit them to the brain, thereby creating the images of the object being viewed. With a little learning the user can distinguish between a knife and a fork on the dining table or distinguish between the lift buttons, read letters and numbers, etc. The device originally announced in 2009 has been extensively tested at the University of Pittsburgh Medical Centre’s UPMC Eye Centre.
In another related development, a team of scientists led by Prof Michael Beauchamp at the University of Texas is exploring the possibility of electrically stimulating the visual cortex of the brain by means of electrical implants. He, too, believes that we see not with our eyes but with our brains and if electrical images generated from the visual objects could be transferred to the correct region of the brain, vision could be restored.
About 10 per cent of the blind experience vivid hallucinations. This is attributed to the hyperactivity of the visual cortex of the brain, and the images seen can be in exquisite detail. It is envisaged that a webcam fitted on the glasses of the blind person could be connected to an implant in the brain to restore vision. The work was recently published in a leading science journal (Nature Neuroscience(2012) doi:10.1038/nn.3131).
Portable sign language translators
The deaf may be able to communicate with one another using sign language but this language is not understood by non-deaf persons unless they are trained to recognise what each gesture means. Now a group of engineering technology and industrial design students from the University of Houston have created a prototype translator, appropriately called MyVoice, that can recognise the signals and translate them into sound.
It is a portable device that incorporates a microphone, speaker, soundboard, video camera and monitor. The device reads the hand gestures and then audibly states the message. It can also do the reverse — listen to the message from a non-deaf person and translate it into hand gestures that could be understood by the deaf person. Still in its early stages of development, the device is expected to compete with an already-existing product known as the AcceleGlove that, however, works only as a one-way deaf-to-hearing translator. Worn as a glove, it determines the hand gestures, and expresses those in written text or as spoken words.
New mosquito resistant clothing
According to WHO, some 200 million people suffer from malaria each year. It caused about 655,000 deaths in 2010, though the actual number may be much higher as many deaths are often unrecorded. Children below the age of five are the most vulnerable. Most of the cases of severe disease are caused by the mosquito Plasmodium falciparum, though four other mosquito species are also known to cause milder forms of malaria.
The disease is widespread in sub-Saharan Africa, Asia and the Americas, particularly in the tropical and subtropical regions near the equator where high humidity, warm temperatures, constant rainfall and stagnant waters provide ideal breeding grounds for mosquito larvae. The development of resistance to most drugs has further aggravated the problem. A number of sprays and lotions have been developed that repel mosquitoes and mosquito repellent bed nets are commonly used.
Now a company in Portugal, “Nanolabel”, has invented a new treatment for clothing that it claims to be much superior to existing repellents. The process involves the use of nanotechnology. Clothes are impregnated with amorphous silica (sand) nanoparticles that have a chemical repellent embedded within their core. The exact nature of this repellent is being kept a closely-guarded secret. The work was carried out at the Institute of Hygiene and Tropical Medicine in Lisbon.