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    CLONING
    January 20, 1998 - United States

    American researchers announced they have cloned calves that may produce medicinal milk. Dr James Robl at the University of Massachusetts and Dr Steven Stice of Advanced Cell Technology were the first to clone cows from fetal cells in which human genes were spliced into cattle DNA. Creating two identical, genetically engineered calves are a step towards the mass production of human drugs in animals. Their goal was to turn cows into drug factories, mass producing milk that contains human proteins important for treating human diseases. The scientists used a variation on the techniques previously used in Edinburgh, Scotland, to create the cloned sheep Dolly. Cows would be better producers of the proteins than sheep because they make more milk.

    MOVIE
    January 20, 1929 - United States

    The first full-length motion picture in the U.S. filmed outdoors was released by Fox Film Corporation. Re-titled as In Old Arizona, it was adapted from a short story by O. Henry, “The Caballero's Way.” The black and white Western was a box-office hit, starring Oscar-winning Warren Baxter as “The Cisco Kid,” a carefree Mexican bandit who outwits the sheriff trying to capture him. A review in the New York Times referred to “the novelty of the Movietone,” listed various incidental sounds and particularly noted the welcome new consideration that the sound of galloping grew fainter and fainter in the distance. Film locations included Zion National Park, Bryce Canyon, the Mojave Desert in California and San Juan Capistrano mission.

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    "...Change; we don't like it, we fear it, but we can't stop it from coming. We either adapt to change, or we get left behind. It hurts to grow, anybody who tells you it doesn't is lying. But here's the truth: Sometimes the more things change, the more they stay the same. And sometimes, oh, sometimes change is good. Sometimes change is everything...."
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    Myth: Staring at a computer screen all day is harmful to the eyes. Fact: Spending the day staring at a screen can tire or strain your eyes, but it will not hurt them. Make sure lighting doesn't create a glare on your screen. When spending long periods at your keyboard, take a break now and then to rest your eyes to reduce fatigue. Also, don't forget to blink. Your eyes need to stay lubricated to feel comfortable. Drug Abuse
    about Facts about Drugs

    Facts about drugs can protect against drug abuse. Legal drugs, such as alcohol and tobacco, kill more people than illegal drugs. Tobacco (smoking cigarettes) kills more people than any other drug. Illegal drugs including heroin, cannabis, ecstasy and amphetamines can have unknown or dangerous ingredients. Mixing drugs, especially with alcohol, can be fatal.

Circuit Breakers :

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ARTICLE INFORMATION :

Most non-electricians know little about circuit breakers. Are you planning to redo the wiring in your home? Using the wrong breaker can cause you a lot of power failures. Quiz your electrician to know more about breakers.

ARTICLE CONTENT :

A circuit breaker is an electrical device used to automatically break open an electrical circuit when it becomes overloaded. This is a safety precaution that can save a home or building from having a major fire or electrical disaster.

To determine the ideal breaker, you have to consider the type of voltage you are using, the trip point, and the overload protection. These are important factors for the safety of your home and family.

There are different types of voltage breakers; the low voltage circuit breaker is the most common type, which is used in homes. Low voltage breakers are the easiest way to install, since you only have to install them on breaker panels.

Miniature circuit breakers or MCBs use the lowest low voltage. It is known to carry electricity of not more than 100 amps; MCBs are also capable of holding electric charges of not more than 1,000 amps. Next to MCBs, are the Molded Case Circuit Breakers or MCCBs.

MCCBs are ideal for 1,000 amps and can safely disconnect from electricity that goes beyond ten times its capacity. They are also called a magnetic circuit breaker, because they use an electromagnetic power solenoid to break the circuit when there is too much electricity flowing through it.

Medium Voltage Circuit Breakers are the next type. Its capacity is to hold amps that can reach between 1,000 and 72,000 before they break. Their performance is relative to the model and brand. Westinghouse breakers are known for its quality of performance.

Medium Breakers are found in large buildings and businesses, and are enclosed in switchboxes or indoor cabinets. Under this type of breaker are three sub-types, vacuum, air, and SF6 breakers.

The vacuum breakers can maintain a power arc in a vacuum by letting air back into the breaker when it is tripped. An air Circuit breaker is equipped with two spring loaded contacts close together in an air-enclosed environment, when the breaker is tripped; the spring snaps open and pushes the contacts away from one another.

SF6 breakers have an arc produced in a chamber of sulfur hexafluoride gas, which reacts to the presence of higher than a regular voltage. It increases in density to stop the arc.

The high voltage breakers are the ones that are capable of holding more than 72,500 volts of electricity. They are found outdoors in a chain-link enclosure together with high voltage power lines. They are operated by solenoid switch which activates the fill the arc-chamber, when too much power flows through them.

The trip point is the second consideration in choosing the ideal circuit breaker. The point at which the breaker will trip can be set at low, medium or high sensitivity to prevent your wiring from heating.

Breaker overload protection is critical. Westinghouse breakers have overload protection that are similar to hydraulic and earth leakage breakers, providing custom protection. This type of circuit breaker senses ground faults and excessive flow of electricity.

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  • Relectric
    At relectric you will find the circuit breakers you want. We have many brands of circuit breakers you can choose from.

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  • November 30, 2014Date Added :
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