100 Amazing Inventions
41. What is the importance of DNA finger printing?
DNA FINGER PRINTING:
In September 1984, Dr. Alec Jeffreys, a geneticist from
the university of Leicester in Great Britain was studying hereditary diseases
in families when he realized that DNA patterns are unique to each person.
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| DNA Fingerprinting |
So, he invented the test that is today known as DNA
fingerprinting. This test can identify and evaluate the genetic information
called DNA or deoxyribonucleic acid, in a person's cells.
It is called a 'fingerprint' because it is very
unlikely that any two people would have exactly the same DNA information,
in the same way that it is very unlikely that any two people would have
exactly the same fingerprint. DNA fingerprinting is used to determine
whether a family relationship exists between two people, to identify
organisms causing a disease, and to solve crimes.
42. What are self driving cars?
SELF DRIVING CAR:
Driver error is the most common cause of traffic
accidents. So, obviously, cars that drive themselves should be able to
reduce the number of road accidents.
However, this is easier said than done. The Idea of self
driving cars gained widespread public exposure at GM's Futurama exhibit
at the 1939 World's Fair.
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| Self Driving Truck |
The first self driving car was unveiled in 1977 by S.
Tsugawa and his colleagues at Japan's Tsukuba Engineering Laboratory.
The car was equipped with two cameras that used analogue computer
technology for signal processing. Automakers are developing complex
systems that allow cars to drive themselves.
In May 2014, Google presented a new concept for their
driverless car that had neither a steering wheel nor pedals. Google
plans to make these cars available to the public in 2020.
43. Why are superconductors a significant discovery?
SUPER CONDUCTORS:
You might have learnt that conductors, such as
metal, allow electricity to pass through them easily, while
insulators like plastics barely let it pass through at all.
Actually, all materials conduct electricity, under
the right conditions, but some conduct more easily than
others.
When wee say a metal conducts electricity well, we really mean it offers little or no resistance when you try to
make a current flow through it. At the same time, when we say
plastics insulate well, we're actually saying that they put up
high resistance to electric currents.
In 1911, a Dutch physicist called Onnes was
investigating the resistance of metals at very low
temperatures. He discovered that when Mercury is cooled to
about -2690 C. it offers no resistance to an electric current. He called this surprising effect superconductivity.
During the 1950s, more work was done on superconductors, and it was realized that they represented are one of the greatest of scientific discoveries. This is because if you set up a current in a loop of a superconductor, there is nothing to stop it as there is no resistance.
Therefore, it will keep flowing forever, forming a very powerful electromagnet. In fact, the most powerful magnetic fields on Earth are produced using superconductors.
44. Why does the stent represent a milestone in medical history?
STENT:
In medicine, a stent is a tube or other device placed in the body to create a passage between two hollow spaces.
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| Placing a Stent |
There are a wide variety of stents used for different purposes, from expandable coronary, vascular, and billiard stents, to simple plastic stents used to allow the flow of urine between kidney and bladder.
Julio Palmaz, a radiologist, is known for inventing the balloon expandable stent, for which he received a patent in 1985. This patent has been included on the list of the ten most important inventions of all times.
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| Stent |
The first use of ac coronary stent is attributed to Jacques Puel and Ulrich Sigwart when they implanted a stent into a patient in France in 1986.
In October 1987, Palmaz implanted his first stent on a patient in Germany. later, the first Palmaz-Schatz coronary stent was implanted in Brazil. All these procedures were very successful.
45. What is a touchpad?
TOUCHPAD:
A touch pad is a device for pointing on a computer display. It is an alternative to the mouse.
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| A Tablet |
It was invented by George E. Gerpheide in1988. The touchpad is a flat area, located beneath your keyboard. When you move your finger across the touchpad surface a corresponding mouse pointer moves around your computer screen. With a touchpad, you perform clicking actions to open or select things on screen by using the right and left buttons on the bottom of the touchpad.
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| Touch Pads for Phone, Tablet, Laptop |
Under the soft skin of the touchpad, there is an array of sensors which create an electrical field. The finger changes the character of the electrical field. allowing the user to drag a cursor across the screen.