Scientists have created a radically new type of graphene speakers

Practically all the existing dynamics work on the same principle: the electric signal generates oscillations of the coil in the field of a permanent magnet, it drives the diffuser, and this, in turn, creates air vibrations and sound waves of the required frequency. But in the future, everything can change, because scientists from the British University of Exeter have created a fundamentally new type of dynamics from graphene, which does not need any mechanical vibration.

The principle of the new dynamics is based on a change in the temperature of graphene, the changes of which lead to the appearance of sound. Previously, graphene has already been used to create speakers, but in the past it was made from diffusers, which led to an increase in the efficiency of the device. From the new dynamics, all the moving parts disappeared, which allowed to reduce its size and increase its effectiveness. The speaker is made in the form factor of a microprocessor the size of a thumbnail. Inside the processor case, in addition to the speaker itself, the amplifier and even the graphic equalizer are hidden.

The thermoacoustic principle of operation allows you to convert the temperature into sound or vice versa – to convert sound vibrations into heat. This effect was first described at the end of the XIX century by the scientist Lord Rayleigh. In the middle of the twentieth century, interest in the interrelation between sound and heat greatly increased, since it was necessary to study the instability in combustion chambers with huge temperature differences. To date, there are thermoacoustic engines and even thermoacoustic refrigerators. But thermoacoustic speakers, and even from graphene, so far no one has created.

Graphene is an excellent conductor, therefore, by passing electrical impulses through it, you can quickly heat up and cool it. The grafen membrane expands and contracts, which affects the ambient air and generates sound waves. How good is the sound obtained in this way? The team of researchers claims that the graphene thermoacoustic speaker allows to get a “rich sound palette”, depending on how and where it is supplied with electricity. Heating and cooling cycles allow you to create multiple audio frequencies at the same time, while mixing them together, amplifying and tuning their sound. Scientists even managed to obtain ultrasound.

The results of research by British scientists were published in the journalScientific Reports.

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Created by the power of thought, the exoskeleton of the hand

Swiss engineers from the Federal Polytechnic School of Lausanne created a working prototype of the exoskeleton of the hand that can be controlled by the power of thought. The developers were able to do without implanting the electrodes under the skin, placing them on a special rubber helmet.

Impulses of the brain are transmitted from the helmet to the metal “tendons”, which are fixed on the wrists and fingers of the wearer with the help of Velcro fasteners, thereby causing the patient’s hand to move.

The exoskeleton itself is easy to use, installed in a few minutes, and still has the function of controlling the movement of the eyes, which was provided for completely immobilized people. It has already been tested for survivors of stroke and spinal injury patients, now the developers want to improve its work in such a way that it helps people fulfill their daily tasks.

In the course of research conducted by developers in the process of testing the exoskeleton, it turned out that when the thought is controlled by the apparatus of one hand, the brain regions responsible for the movement of the second arm are activated in the patient. Scientists plan to use this feature to improve development management and to complicate its design.

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In Japan, created the perfect medicine for influenza

Japanese pharmacists announced the creation of a drug against the flu, capable of killing the virus during the day. It operates much faster than existing analogues and requires only a single admission, reports the Washington Post.

The main means of fighting against influenza is vaccination. Drugs that treat a person who has already fallen ill, there is little – the fact is that it is difficult to work on a virus that managed to get inside the cells. The Japanese company Shionogi decided to change the situation by applying to the influenza the experience gained in the development of a drug against HIV.

Usually, drugs against influenza are aimed at stopping the spread of viral particles from already captured cells. The new agent works earlier, even at the stage of infection of cells due to the blocking of the metalloenzyme. Curiously, this enzyme was similar in HIV and influenza.

The study showed that the drug, developed by Shionogi, killed the flu virus in the patient’s body within 24 hours. This is much faster than any of the available analogues on the market. For example, a popular Tamiflu drug requires three times as much time. According to the researchers, rapid destruction of the virus reduces the risk of infecting others. As for the symptoms of the disease, it takes as much time to completely eliminate Shionogi as Tamiflu. However, immediate relief from the new drug comes faster. In addition, it is enough to take it once, rather than drink for five days, like Tamiflu.

Currently, the drug is being tested. Impressive results of the first works forced the Swiss pharmaceutical giant Roche to acquire a license for its distribution. The use of the drug in Japan can be approved already in March, but its appearance in the US and other countries should not be expected until next year.

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