Polio vaccines are vaccines used to prevent poliomyelitis (polio). There are two types:
one that uses inactivated poliovirus and is given by injection (the Salk vaccine), and one
that uses weakened poliovirus and is given by mouth. The two vaccines have eliminated
polio from most of the world, and reduced the number of cases reported each year
from an estimated 350,000 throughout the years.
Intermodal containers are primarily used to store and transport materials and products
efficiently and securely in the global containerized intermodal freight transport system,
but smaller numbers are in regional use as well. These containers are known under a
number of names, such as simply container, cargo or freight container, ISO container,
shipping, sea or ocean container, container van or (Conex) box, sea or c can.
Silicon chips can contain logic gates, computer processors, memory and special devices.
The chip is very fragile and so is normally surrounded by a tough plastic package.
Electrical contact with the chip is provided through metal legs sticking out of the
package.
A laser is a machine that makes an amplified, single-color source of light. The beam of
light from the laser does not get wider or weaker as most sources of light do. It uses
special gases or crystals to make the light with only a single color. Then mirrors are used
to amplify (make stronger) that color of light and to make all the light travel in one
direction, so it stays as a narrow beam, sometimes called a collimated beam.
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