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Sometimes What Feels Like an Infection May Be an Allergy
Written by Mario Ritter

I'm Gwen Outen with the VOA Special English Health Report.

Pollen from flowers is a common cause of allergies.
An allergy is an unusually strong reaction to a substance.  Many different things can cause allergies.  The most common cause is pollen.  Trees and many other kinds of plants release pollen into the air to reproduce successfully. 

Different kinds of plants produce pollen at different times of the year.  For example, trees usually produce pollen in the spring.  Grasses pollinate in the summer.  Weeds produce pollen in the autumn. 

Many other things can cause allergies.  They include organisms such as dust mites and molds, dead skin particles on dogs and cats, chemicals, plants, medicines and some common foods.  Insect bites also can cause allergic reactions.

There are several kinds of allergic reactions.  The most common reaction is watery, itchy eyes and a blocked or watery nose.  Other reactions include red, painful, itchy skin.  Some allergic reactions can be life-threatening.  For example, allergic reactions that block breathing tubes are very dangerous.

Doctors say there are several ways to treat allergies.  They say people should try to avoid the substances that cause allergic reactions.  Medicines called antihistamines are used to treat allergies. 

Another treatment is called immunotherapy.  This involves injecting a patient with small amounts of the allergy-causing substance.  Larger and larger amounts are given.  Over time, the patient develops a resistance to the allergy-causing substance. 

This treatment is usually effective against allergies to small particles in the air, like pollen or dust, and insect bites.  However, this treatment is generally not used for allergies to foods.  In some cases, there can be life-threatening reactions.

The National Institute of Allergy and Infectious Diseases says four percent of Americans have severe food allergies.  On June twenty-fourth, the institute announced a new food allergy research group.  Plans call for twenty-two million dollars to be spent over five years.

Scientists will look for new ways to treat and prevent food allergies.  Studies will take place at five research centers.  The first project will involve testing experimental new treatments for allergies to peanuts.  The second project will involve a study of four hundred babies with allergies to milk or eggs.

This VOA Special English Health Report was written by Mario Ritter.  Our reports on the Web at voaspecialenglish.com.  I'm Gwen Outen.

Igor Sikorsky: Aircraft and Helicopter Designer
Written by Marilyn Christiano

(MUSIC)

ANNOUNCER:

Igor Sikorsky on the cover of Time magazine.
Now, the VOA Special English program, EXPLORATIONS.  Today Shirley Griffith and Steve Ember tell about Igor Sikorsky.  He was a leader in designing and building new kinds of aircraft.

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VOICE ONE:

Igor Sikorsky was born in the city of Kiev, Russia, on May twenty-fifth, eighteen eighty-nine.  His mother was a doctor.  His father was a professor of psychology.

Igor became interested in science when he was very young.  He was especially interested in the possibilities of human flight.  As a ten-year-old boy, he started building toy flying machines out of paper and bamboo.

One was a helicopter.  Igor turned the blades and held them in place with a thin piece of rubber.  When he let go of the rubber, the blades turned in the opposite direction.  And the little helicopter flew around the room.

VOICE TWO:

Igor dreamed of building a real helicopter.  But he had little hope.  Later he said:  "I had read with great interest the stories of French writer Jules Verne.  In some of the stories, Verne described a helicopter.  Many intelligent people, however, said such a machine would never fly.  So I decided my dream would remain just that."

Sikorsky entered the naval college in St. Petersburg.  Then he studied engineering at the Polytechnic Institute in Kiev.  He did not know that,a few years earlier, Americans Orville and Wilbur Wright had succeeded in flying.

VOICE ONE:

In nineteen-oh-eight, Sikorsky traveled to Germany with his father.  He saw a picture in a newspaper of Orville Wright and his airplane.  "Within twenty-four hours," he said, "I decided to change my life's work.  I would study aviation."

The next year, Sikorsky went to Paris.  At that time, Paris was the center of aviation in Europe.  Sikorsky met several French pilots, including Louis Bleriot, the first person to fly across the English Channel.  The pilots gave him advice about building successful airplanes.

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VOICE TWO:

Sikorsky returned home to Kiev after learning all he could in Paris.  He decided to build a helicopter, even though many experts said it was not possible.

He tested his first helicopter in nineteen-oh-nine.  It weighed too much and had too little power.  It could not get off the ground.  He tested his second helicopter a year later.  That one could lift itself off the ground.  But it was not powerful enough to lift a pilot, too.  After these failures, Sikorsky decided to work on airplanes, instead.

VOICE ONE:

His technique was unusual.  First, he drew pictures of a plane. Then he built it.  Finally, he trained himself to fly it.  In this way, he quickly discovered any problems in the design and was able to correct them.

The first plane Sikorsky designed and built was called the S-Two.  He tested it in the summer of Nineteen-Ten.  Just two years later, another Sikorsky plane -- the S-Six -- won the highest prize at an aviation show in Moscow.

VOICE TWO:

Sikorsky's success helped win him a job as head of the airplane division of the Russian Baltic Railroad Car Works.  That is where he developed his first major new airplane design.

Planes at that time had only one engine.  Sometimes, a plane's propeller pulled masses of flying insects into the engine.  The engine stopped, and the plane crashed.  Sikorsky thought planes would be safer if they had more than one engine.  So he designed a plane with four engines.  He called it "The Grand."

VOICE ONE:

Sikorsky's plane was revolutionary.  It was the first to have more than one engine.  It was the first to have a closed area for the pilot and passengers.  And it was the first to have a toilet.

After designing "The Grand," Sikorsky designed an even bigger airplane.  He called it the "Ilia Mourometz," the name of a famous Russian who lived in the tenth century.  He made a military version of this plane.  It became the most successful bomber used in World War One.

(MUSIC)

VOICE TWO:

Igor Sikorsky left Russia at the start of the revolution in nineteen seventeen.  He stayed for a while in Britain and France.

Then he went to the United States.

He arrived with little money and no real chances for work.  America's aviation industry was new and very small.  There were no jobs.

In nineteen twenty-three, however, he got help from a group of Russian exiles in the United States.  They gave him enough money to start his own aviation company, Sikorsky Aero Engineering.  It was on Long Island, east of New York City.

VOICE ONE:

Sikorsky's greatest success during this period was designing seaplanes.  These planes could land on ground or on water.  They could fly long distances.  The Pan American airline company used them to fly from North America to Central and South America.

In nineteen twenty-nine, the Sikorsky company became part of the United Aircraft Corporation.  The re-organized company produced a series of large planes known as flying boats.

These planes were big enough and powerful enough to fly across oceans.  They made it possible to move people and goods quickly from the United States to Europe and Asia.  Passengers on flying boats rested in soft seats.  They ate hot meals.  Air travel had become fun, as well as safe.

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VOICE TWO:

By nineteen thirty-eight, Igor Sikorsky decided to experiment with helicopters again.  It had been thirty years since his first unsuccessful attempts.  Through those years, he had written down ideas for possible new designs.

The first helicopter Sikorsky built in America was the V-S-Three-Hundred.  It was a 
Igor Sikorsky's first successful helicopter, the VS-300.
skeleton of steel tubes.  In its first test flight, it rose about a meter off the ground.

Sikorsky then tested nineteen more designs.

VOICE ONE:

The final design had one main rotator, or rotor.  The rotor was connected to three long blades on top.  These blades turned around like an album on a record player.  They lifted the helicopter into the air.  A smaller rotor, with shorter blades, was at the back end.  Those blades turned around like the wheel of a car.  They kept the body of the helicopter pointed forward.

This remained the basic design of all Sikorsky helicopters.

VOICE TWO:

By nineteen forty-one, the V-S-Three-Hundred had set all world records for helicopter flight.  Military versions were made and some were used in the last years of World War Two.  Most people, however, still did not accept the new flying machine.  They said the helicopter had to prove its worth.

It did that during the war in Korea in the early nineteen fifties.

Helicopters take off straight into the air.  They can land just about anywhere.  They do not need long airport runways like planes.  During the Korean War, helicopters flew into battle areas to rescue wounded soldiers.  They flew the men quickly to medical centers set up away from the fighting.  This greatly improved the men's chances of survival.

VOICE ONE:

Igor Sikorsky, the man most responsible for successfully designing and building helicopters, thought helicopters would be a common form of transportation.  People, he said, would use them instead of automobiles.  They would fly into a city, land on top of a building, go to work, then fly home again.

This has not happened.  Privately-owned helicopters are not common.  Yet helicopters have proved their value in other ways.

Companies use them to transport heavy equipment to hard-to-reach places.  Farmers use them to put insect poisons on their crops.  And emergency teams use them to rescue people from fires and floods.

VOICE TWO:

Igor Sikorsky continued as an engineering adviser to his aircraft company until he died in Nineteen-Seventy-Two.  He was one of the best-known and most respected leaders in international aviation.

He received more than ninety major awards and honors from many countries and organizations.

He always said, however, that his greatest satisfaction did not come from receiving honors.  It did not come from being the first person to design new kinds of aircraft.  Igor Sikorsky said his greatest satisfaction came from knowing that his helicopters were responsible for saving lives.

(MUSIC)

ANNOUNCER:

This Special English program was written by Marilyn Rice Christiano.  Your narrators were Shirley Griffith and Steve Ember.  I'm Ray Freeman.  Join us again next week for another EXPLORATIONS program on the VOICE OF AMERICA.

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