Jan 31, 2013

Mammals that lay eggs and suckle their young

The duck-billed platypus (Ornithorhynchus anatinus) and the echidna or spiny anteater (family Tachyglossidae), indigenous to Australia, Tasmania, and New Guinea, are the only two species of mammals that lay eggs (a non-mammalian feature) but suckle their young (a mammalian feature). These mammals (order Monotremata) resemble reptiles in that they lay rubbery shell-covered eggs that are incubated and hatched outside the mother's body. In addition they resemble reptiles in their digestive, reproductive, and excretory systems, and in a number of anatomical details (eye structure, presence of certain skull bones, pectoral [shoulder] girdle, and rib and vertebral structures). However they are classed as mammals because they have fur and a four-chambered heart, nurse their young from gland milk, are warm-blooded, and have some mammalian skeletal features. (The Handy Science Answer Book, compiled by the Science and Technology department of the Carnegie Library of Pittsburgh)

Jan 30, 2013

When did globalization begin?

There are many different starting dates for globalization as there are definitions of the term, in part because different definitions suggest different starting points. According to Nayan Chanda of the Yale Center for the Study of Globalization, globalization began eight thousand years ago, because by that time all the forces that would push the process forward were already in place. "Essentially," Chanda wrote in his 2007 book Bound Together, "the basic motivations that propelled humans to connect with others -- the urge to profit by trading, the drive to spread religious belief, the desire to exploit new lands, and the ambition to dominate others by armed might -- all had been assembled by 6000 BCE to start the process we now call globalization."

Other proposed starting dates include Christopher Columbus's discovery of the New World in 1492; the first circumnavigation of the globe, completed in 1522; the Industrial Revolution, which began during the late eighteenth century; the adoption of the prime meridian and the international date line in 1884; and the fall of the Berlin Wall in 1989.

Jan 29, 2013

Glacial Handiwork in USA

Advancing and retreating over a span of hundreds of millions of years, mantles of ice reached farthest into the U.S. 18,000 years ago. By the time the last ice age ended 8,000 years later, glacial handiwork had created some of the country's most distinctive features: the Great Lakes, Puget Sound, the bogs of northern Minnesota, and the bulldozed flatness of the Central Lowland. There ice ground rock into the fine soil in which Iowa, Illinois, and adjacent states grow 40 percent of the world's corn crop. Sand and gravel deposited by glaciers also helped shape the profiles of Long Island and Cape Cod.

Glacier is an enduring accumulation of ice, snow, water, rock, and sediment that moves under the influence of gravity. Glaciers form where the temperature is low enough to allow falling snow to accumulate and slowly transform into ice. This accumulation is most common in the polar regions, but can also occur at high altitudes on mountains even near the equator. Glaciers are complex systems that grow and shrink in response to climate. At the present, glacier ice covers about 15 million sq km (5.8 million sq mi), or 10 percent, of Earth’s land area.

Jan 28, 2013

Remora or Suckerfish

Among many ocean creatures who perform cleaning services, one is the remora, or suckerfish. This bold fish travels with the shark, one of the most feared ocean predators. The remora has a large sucker on top of its head with which it attaches itself firmly to the shark. (Some remoras attach themselves to other large ocean creatures, even whales.) As the shark swims along, the remora travels all over its body removing debris. It gets food and protection - and an occasional feast. Sharks are messy eaters, and when the shark feeds, the remora detaches itself and gobbles up the leftover bits. (Adapted from Grolier Book of Knowledge Encyclopedia)

Jan 27, 2013

The world’s highest peak on land

The world's highest peak on land is Mount Everest in the Himalayas. It is 8,850 meters (29,036 ft) tall – almost 5.5 miles.  The top 14 highest mountains in the world are also found in the Himalayas. (Internet sources)

Jan 26, 2013

A bug that can walk on water

Water Striders can walk on water as easily as we walk on sidewalk. How? Water has a kind of skin, called surface tension, on which the Water Strider can walk.

Water Strider is the common name applied to slender water bug  that is a predator on other insects. It lives on the surface of quiet waters—some species are adapted for life on faster-moving streams—and darts about with great rapidity, using the middle pair of legs as paddles and the hind pair for steering. The front pair of legs is adapted for grasping prey. Fine, dense hairs on the feet keep the insect from breaking the water's surface film. (Adapted from ‘Science Challenge’, and Encarta Encyclopedia’)

Jan 25, 2013

Daydreaming: It's Not for the Lazy

What do people daydream about? "Their unmet wants and unassuaged fears," says Eric Klinger, Ph.D., a psychologist at the University of Minnesota at Morris and author of Daydreaming: Using Fantasy and Imagery for Self-Knowledge and Creativity. Daydreams are inherently spontaneous bursts of imagination in which you work out problems, dream up solutions, and plan for the future. You roll in and out of them so often that, more than likely, you spend half of your waking hours in a dream.

Don't believe it? What do you do when you brush your teeth in the morning? When you drive your car? When you pour a cup of coffee?

"Daydreaming seems to be a natural way to use brainpower efficiently," explains Dr. Klinger. "I think that the brain machinery is set up in such a way that when we're not using full capacity, we automatically cut out and start working over other things. Our minds wander into a review of the past or rehearse what's coming up."

Jan 24, 2013

The Balkan States

Balkan Peninsula, in southeastern Europe, is bounded on the east by the Black and Aegean seas, on the south by the Mediterranean Sea, and on the west by the Adriatic and Ionian seas. It comprises the countries of Slovenia, Croatia, Bosnia and Herzegovina, the Former Yugoslav Republic of Macedonia, Serbia and Montenegro (formerly the Federal Republic of Yugoslavia), Albania, Greece, Romania, Bulgaria, and European Turkey. The northern boundary is geographically defined as the Sava River; the lower Danube River from the point, at Belgrade in Serbia, where the Sava joins it; and a line drawn arbitrarily from the upper Sava to the Adriatic near Rijeka, Croatia. This boundary is easily recognizable on a map and, with a few exceptions, encompasses the countries generally defined as Balkan states, but it has no physiographical justification. It is historically justifiable because the region so defined (together with Romania and excluding Montenegro, Dalmatia, and the Ionian Islands) constituted most of the European territory of the Ottoman Empire from the late 15th to the 19th century.

Jan 23, 2013

How was the inch developed?

What we now know as the inch (from Latin uncia, or "12th part") was defined as 1/12 foot by the Romans. It was roughly a thumb's breadth, while a foot was roughly the length of a human foot. The Romans introduced the inch to Britain, where it was incorporated into the English system of weights and measures. The English made their own contribution to inch lore: In 1305, King Edward I decreed that an inch should be the measure of three dried barleycorns. (The Book of Answers, by Barbara Berliner)

Jan 22, 2013

Calculus: Mouth, Not Math

That sticky, invisible biofilm (a colony of microorganisms) that forms daily on your teeth is called plaque. If it's allowed to, harden, it's called tartar or calculus. Plaque contains bacteria, which turn sugars and starches from food into an acid that causes tooth demineralization (dissolving of the enamel) and leads to tooth decay (cavities, or caries). Calculus irritates the gums, which brings about gingivitis (inflammation); if left untreated, this can develop into the more serious periodontal disease.

The bacteria that live in the human mouth are not normally harmful, but if they are not removed by brushing, they can build up into a thin layer. Then the bacteria nearest the tooth surface begin to metabolize food with anaerobic respiration (without oxygen); the waste ducts of that process are very acidic.

Daily brushing, flossing, and use of mouthwash are the primary preventative methods. Dentists can remove plaque in a process called scaling, if gum disease is present, root planting is utilized. (All Facts Considered, by Kee Malesky)

Jan 21, 2013

The World Bank and the IMF

In July 1944, financial experts from forty-four countries attended the United Nations Monetary and Financial Conference held in Bretton Woods, New Hampshire. The purpose of the conference was to make financial arrangements for the postwar world. The participants knew that the two most pressing needs would be capital for long term reconstruction and loans for short-term currency stabilization. Therefore, they recommended the creation of two institutions to meet those needs: the International Bank for Reconstruction and Development (IBRD) and the International Monetary Fund (IMF).

The purpose of the IBRD was to finance the reconstruction of Europe and Japan, whose cities and industries had been devastated by aerial bombing. After achieving this goal, the IBRD redefined itself. Its new mission was to alleviate poverty and support growth in the developing world. In 1960, the International Development Association (IDA) was formed to complement the work of the IBRD. The IDA'S mission was to make loans to the world's poorest countries on terms more flexible than those offered by the IBRD. Together, these two institutions constitute the World Bank, which today provides low-interest loans, interest-free credit, and grants to the developing world.

Jan 20, 2013

Quantum mechanics – the science dealing with the behavior of matter and light on the atomic and subatomic scale.

Quantum mechanics attempts to describe and account for the properties of molecules and atoms and their constituents—electrons, protons, neutrons, and other more esoteric particles such as quarks and gluons. These properties include the interactions of the particles with one another and with electromagnetic radiation (i.e., light, X rays, and gamma rays).

One of the most remarkable scientific advances of the 20th century is the development of quantum mechanics - the description of the behavior of matter on the atomic and sub-atomic scale. It is now a powerful tool for understanding the behavior of atoms and molecules, and is vital to physicists, chemists and biochemists alike.

Its roots lie in Max Planck's discovery at the turn of the century that the radiation from a hot object can be successfully described only if it occurs with specific amounts of energy - "quanta" - rather than with a continuous range of energies. This discovery led ultimately to the description of light in terms of "particles", known as photons, the name coined in 1926 by the American Gilbert Lewis.

Jan 19, 2013

Restless Earth

On a world map, the east coastline of South America bears an uncanny likeness to the shape of the west coast of Africa. Look at the edges of the continental shelves of these two continents, a couple of hundred metres under the sea's surface, and the resemblance is even more striking. The two would fit together like pieces of a giant jigsaw. In fact, they once did. The idea of continental drift, once dismissed out of hand, is now well established in science. The major land masses or continents have changed less through time than the Earth's crust under the oceans. The oceanic crust has continually formed new patches from molten rocks welling up from below, while other patches melt back into the depths again. The continents have been carried around like giant rafts on these changing shapes of oceanic crust.

-- Part of the evidence

Evidence for continental drift comes from many areas, including fossils. Remains of the reptile Lystrosaurus have been found in South Africa, Antarctica, India and China, suggesting these lands were joined many years ago.

-- First to propose

The idea of continental drift has been around for centuries. First to propose a scientific explanation was German weather expert Alfred Wegener (1880-1930), in 1912. But political problems, world wars and Wegener’s background in meteorology meant his suggestions were not taken seriously until 1960s. (Adapted from 'World of Science')

Jan 18, 2013

Allergies

Allergies are overreactions of the immune system to foreign substances. Any substance that triggers an allergic reaction is called an allergen. Pollen, mold spores, dust mites, foods, alcohol, medications, chemicals, and animal dander are common allergens. Allergens cause the body to produce and release histamine and other "mediator" compounds. These compounds affect local tissues and organs, causing symptoms of the reaction.

Symptoms may include itchy or blistering skin, stuffy or runny nose, sneezing, shortness of breath, red or swollen eyes, headache, swelling of the lips or tongue, nausea, vomiting, or diarrhea. If the release of mediator compounds is sudden or extensive, the allergic reaction may be severe, resulting in anaphylactic shock. U.S. incidence of allergic diseases has grown dramatically in recent years. An estimated 60 million Americans suffer from allergies; more than 700 die each year due to allergies, about half of them due to drug allergies from penicillin.

Measures such as staying away from poison ivy and eliminating certain foods from the diet can prevent many problems. Medications such as antihistamines and corticosteroids are helpful in treating allergic reactions. Prompt injection of the hormone epinephrine (adrenaline) can stop anaphylactic shock, saving the person's life. (New York Times ‘Guide to Essential Knowledge’)

Jan 17, 2013

Florida used to be part of Africa

Bedrock reveals that Florida was part of Africa before ancient landmasses merged to form the supercontinent Pangaea about 300 million years ago. When Pangaea broke apart 200 million years ago (creating the Atlantic Ocean), Florida stayed attached to North America. (National Geographic)

Jan 16, 2013

A Barrel of Energy

One barrel of crude oil contains 42 gallons. When refined, it yields approximately 19.4 gallons of motor gasoline. The remainder of the barrel produces distillate fuel oil, residual fuel oil, jet fuel, and other products (ink, crayons, tires, deodorant, and heart valves). That 42 gallons of oil will release six million British Thermal Units (one BTU is the amount of energy required to raise the temperature of one pint of water one degree Fahrenheit; it's equal to one match tip). A typical American uses about one million BTUs every day.

The amount of petroleum products consumed in the United States is not tracked as such by the Department of Energy; rather, it counts "product supplied." Its system “measures the disappearance of petroleum products from primary sources; [this] approximately represents consumption of petroleum products." We used 3,290,057,000 barrels (more than 137 billion gallons) in 2008. (All Facts Considered, by Kee Malesky)

Jan 15, 2013

Some of the catastrophic world events during 1968 and 1969

The years 1968 and 1969 were racked with war, violence, terrorism, and civil unrest around the world. Wars raged in Vietnam and Nigeria; Soviet and Chinese troops skirmished in a continuing border dispute; Soviet troops entered Czechoslovakia to quell a movement toward liberalization; and El Salvador invaded Honduras. Coups d'etat toppled governments in 'Iraq, Syria, Sierre Leone, Dahomey, the Congo, Mali, the Sudan, Libya, the Netherlands Antilles, Peru, Panama, and Bolivia; states of emergency were declared in Spain, Malaysia, and Chile; violent unrest occurred in West Germany, Spain, Bombay, Pakistan, Argentina, Kenya, and the United States; and student protests erupted in Paris, Mexico City, Czechoslovakia, Argentina, and the United States. United States and Israeli airliners were hijacked, and two Israeli airliners were attacked by terrorists. Moreover, a number of leaders were assassinated, including Somalian president Abdirascid Ali Scermarche; US civil rights leader Martin Luther King, Jr.; US presidential candidate Robert E. Kennedy; US ambassador to Guatemala John Gordon Mein; and Mozambique Liberation Front leader Eduardo Chivambo Mondlane. (Footnote to November 16, 1969 message from the Universal House of Justice; ‘Messages from the Universal House of Justice, 1963-1986’) 

Jan 14, 2013

The smallest country on earth

Vatican City, the seat of the Roman Catholic Church in Rome, is the smallest country. At 0.16 square mile, it is less than quarter the size of the next smallest country, Monaco (0.76 square mile). Vatican City became an independent country in 1929. It is surrounded by Rome, Italy. Its 750 inhabitants are ruled by the Pope and a committee of three cardinals. Vatican City has no permanent citizens. Citizenship of the Vatican City is conferred upon those who work at the Vatican (as well as their spouses and children) and is revoked when they stop working there. The country’s economy is also unique: it is the only non-commercial economy in the world. Instead, the Vatican City is supported financially by contributions of Catholics worldwide, the sale of postage stamps and publications, and tourism. (Adapted from The Book of Answers, by Barbara Berliner, Wikipedia, and other Internet sources)

Jan 13, 2013

What do you mean by that? -- "A hair-raising experience"

This idiom is based on an actual scientific phenomenon. Thanks to something called the pilomotor reaction, people really do have hair-raising experiences. The pilomotor reaction is one of the body's responses to fear: Nerve endings under the skin cause hair on the head and body to stand up. A hair-raising experience, then, is a frightening one. The pilomotor reaction produces a tingling feeling that has given rise to some other expressions, too" -- it made my skin crawl," for example. (Grolier Book of Knowledge Encyclopedia)

Jan 12, 2013

How do different kinds of music affect plant growth?

In experiments done in the 1960s and 1970s, plants responded best to classical and Indian devotional music. In a controlled environment, plants exposed to these kinds of music had lush and abundant growth and good root development. Exposure to country music or silence brought about no abnormal growth reaction, while jazz produced more abundant growth. With rock music, plants did poorly. Their roots were scrawny and sparse and they seemed to be in a dying stage. Plants exposed solely to white noise died quickly. (The Handy Science Answer Book, compiled by the Science and Technology department of the Carnegie Library of Pittsburgh)

Jan 11, 2013

Our Fishy Family Tree?

Human beings and all other four-legged land animals are believed to have descended from ocean creatures that lived mil lions of years ago. Some biologists believe that these ancestors are strange, primitive fish called coelacanth (pronounced see-luh-kanth). They have six fins. Four move as pairs, as if they were primitive legs. 

Coelacanths existed as long as 370 million years ago, and it was long believed that they were extinct. But in 1938 a fisherman netted one in the Indian Ocean. Over the years more of these rare fish were captured and studied. The German biologists analyzed blood proteins from live coelacanths. They found that these proteins are like the blood proteins of frogs- the earliest land animals. Scientists consider the structure of proteins to be an important clue to relationships among animals: the more alike the proteins, the closer the kinship. Despite the new evidence linking coelacanths and amphibians, many more studies must be done to determine if coelacanths really are our water-dwelling ancestors. (Adapted from Grolier Book of Knowledge Encyclopedia)

Jan 10, 2013

Earth’s magnetic shield

As Earth slowly cooled, most of its layers solidified. Its outer core, however, remained molten, a development that turned out to have important implications for the future of life on Earth.

When conducting metals such as iron and nickel move about, they generate magnetic fields. Because the entire iron-nickel outer core of Earth is constantly in motion, circulating around the inner core because of a process called convection, it produces an enormous magnetic field that extends many thousands of miles out into space.

The significance of this field to life on Earth becomes obvious when one considers the hazards posed by the Sun, a runaway nuclear reactor located just ninety-three million miles away. The Sun's enormous gravity ensures that most of its exploding matter never gets too far away, but some particles do escape. Collectively, they are known as the solar wind. In order to break free of the Sun's gravity, they have to be moving very fast, about a million miles an hour. This high rate of speed makes them dangerous to anything in their path, including life on Earth. Fortunately, the magnetic field generated by the circulating metals in Earth's outer core shields us from these particles.

Jan 9, 2013

Body’s lymphatic system – the vehicle of the immune system

The lymphatic system is composed of lymphatic capillaries, lymph nodes, and organ and tissues such as spleen, the largest and most important of these organs, thymus, tonsils, adenoids, appendix, Peyer’s patches and bone marrow.

The body defends itself against foreign proteins and infectious microorganisms.  When lymphocytes, the effective agents of the immune system, recognize a foreign molecular pattern (termed an antigen), they release antibodies in great numbers; other lymphocytes store the memory of the pattern for future release of antibodies should the molecule reappear. Antibodies attach themselves to the antigen and in that way mark them for destruction by other substances in the body’s defense arsenal.

Lymphocytes, which resemble blood plasma in composition, are manufactured in the bone marrow and multiply in the thymus and spleen. They circulate in the bloodstream, penetrating the walls of the blood capillaries to reach the cells of the tissues. From there they migrate to an independent network of capillaries that is comparable to and almost as extensive as that of the blood’s circulatory system. The capillaries join to form larger and larger vessels that eventually link up with the bloodstream through the jugular and subclavian veins; valves in the lymphatic vessels ensure flow in one direction. Nodes at various points in the lymphatic network act as stations for the collection and manufacture of lymphocytes; they may become enlarged during an infectious disease. In anatomy, the network of lymphatic vessels and the lymph nodes are together called the lymphatic system; its function as the vehicle of the immune system was not recognized until the 1960s.  (Adapted from Encarta Encyclopedia and National Geographic)

Jan 8, 2013

What's Your Learning Style?

Each of us has our own natural learning style that reflects the quality of our mind, says Anthony Gregorc, Ph.D., educator and author of An Adult's Guide to Style. It reflects the way we absorb new information, process it, and use it to form new ideas.

"I started out with learning styles - or mind styles as I call them now - about 20 years ago," says Dr. Gregorc. "I was principal of a lab school for gifted kids and I was watching youngsters in grades 7 through 12 who were not being very successful. We had tried all kinds of curriculum revisions, so what I started to do was observe them in relation to their teachers - to really watch their behavior, to see how they learned."

His approach was somewhat unusual, says Dr. Gregorc, because educators rarely study learners to see how they learn. "We normally take the position that a learner is a learner and if he only tries he can adapt to just about anything," explains Dr. Gregorc. "The implication that's at the root of this is that all of us have the capacity to learn in specific ways. It's just that we haven't been taught to.

"As I observed these youngsters, however, I found that they all had different kinds of styles. And when we tried to get some of them to learn in a style that was different than their own, there was a resistance to it.

"I didn't find the resistance was due to 'laziness' or 'contrariness,' " he hastens to add, "or things of that type. I simply found that there were indeed ways of processing information that are different."

Jan 7, 2013

Erie Canal, USA

The completion of the Erie Canal in 1825, linking Buffalo to the Hudson River near Albany, New York, inaugurated an era of growth for New York. The canal opened a route between the Atlantic Ocean and the Great Lakes that encouraged trading and shipping among the states and with foreign countries. It runs about 363 miles (584 km) from Albany, New York, on the Hudson River to Buffalo, New York, at Lake Erie. The canal contains 36 locks and encompasses a total elevation differential of approximately 565 ft. (169 m). First proposed in 1807, it was under construction from 1817 to 1825 and officially opened on October 26, 1825.

It was the first transportation system between the eastern seaboard (New York City) and the western interior (Great Lakes) of the United States that did not require portage, was faster than carts pulled by draft animals, and cut transport costs by about 95%. The canal fostered a population surge in western New York State, opened regions farther west to settlement, and helped New York City become the chief U.S. port. It was enlarged between 1834 and 1862. In 1918, the enlarged canal was replaced by the larger New York State Barge Canal.

Today, it is part of the New York State Canal System. In 2000 the United States Congress designated the Erie Canalway National Heritage Corridor to recognize the national significance of the canal system as the most successful and influential human-built waterway and one of the most important works of civil engineering and construction in North America.  Mainly used by recreational watercraft in the recent past, the canal saw an upsurge in commercial traffic in 2008. (Adapted from Encarta Encyclopedia and Wikipedia)

Jan 6, 2013

Human Time and Geologic Time

Although it may seem to us that Earth has finally arrived at its ultimate state, this is an illusion based on the egotism of humanity and our inability to comprehend the full dimension of geological time. To put it plainly, humanity has not been an important factor in Earth history. Compared with the age of the planet (about 4.5 billion years), the age of the species Homo sapiens (about 150,000 years) is but the blink of an eye. In quantitative terms, humans have been around for only 0.003 percent of Earth's history, or less than eighteen minutes over the course of a year.

We may understand this intellectually but not intuitively. Because planetary change takes place so slowly, we don't notice it and tend to think it's not happening. Nevertheless, most of the processes that have defined Earth's history, such as plate tectonics, seem to function as they always have. The lithospheric plates, for instance, continue to move at roughly the same rate they have over the last three billion years. At just centimeters per year, this movement is difficult to perceive, but it's nonetheless significant.

Jan 5, 2013

How much newspaper must be recycled to save one tree?

One 35-40 foot (10.6 to 12 meter) tree produces a stack of newspapers 4 feet (1.2 meters) thick; this much newspaper must be recycled to save a tree. (The Handy Science Answer Book, compiled by the Science and Technology department of the Carnegie Library of Pittsburgh

Jan 4, 2013

Beware of taking yourself too seriously

Maybe you still feel a little guilty about a faux pas you made at a party two weeks ago. Maybe you finished next to last at a "fun run" on Saturday. Maybe your new hairstylist scrambled your hair and now you have to live with a weird perm for a month. Maybe all those things happened - but so what if they did?

Whoever you are and whatever you do, you probably take yourself and your setbacks too seriously. You could stand to lighten up, laugh at your mistakes, smile more and let people see that beautiful face of yours.

There's a lot to be gained by brightening your outlook. If you can laugh at yourself, you'll probably cope with obstacles more effectively and rebound faster from disappointments. You'll be able to let off steam better, your self-esteem will rise, and people may even like you more.

But if you insist on taking yourself too seriously, you're bound to get steamrollered by Life, with a capital L. 

No one is immune to taking him or herself too seriously, not even Lawrence Mintz, Ph.D., professor of American studies at the University of Maryland and secretary-treasurer of the American Humor Studies Association, a society of scholars interested in humor.

Jan 3, 2013

Medicine – during 1st to 16th Centuries

By the beginning of the Christian era, the Romans had created a widespread empire that included lands from Gaul (France) through Greece and as far east as Syria. But the center of their empire, Rome, was crowded, dirty, and the frequent victim of epidemics of smallpox, bubonic plague, and other diseases. The Romans adopted important public health measures, building aqueducts to bring fresh water into the city and sewers to carry away wastes. Public baths were established to encourage personal hygiene and special buildings were set aside for care of the sick. War injuries advanced surgery: Roman surgeons could surgically reduce limb fractures, tie ligatures around blood vessels, and cauterize wounds to stop bleeding.

The most influential physician of ancient Rome was a Greek, Galen of Pergamum (ca. 129-ca. 216). He used pulse readings in diagnosing problems, showed that different parts of the spinal cord control different muscles, and demonstrated that arteries contain blood, not air as had been believed. But his misconceptions were many. For instance, he stated that pores connect the two sides of the heart and the liver is the main organ of the blood system. In his 300 known writings on physiology, anatomy, disease, and drugs, over half of which have survived, Galen brought together his ideas and those of predecessors and contemporaries. For more than 10400 years, these writings were considered infallible and were the basis of medical education in Europe.

Jan 2, 2013

Does diet play a part in preventing breast cancer?

The first inklings that food might play a role in breast cancer came from the observation that breast cancer is rare in countries where diets are mainly plant-based. In Japan, for example, where the traditional dietary staple is rice, breast cancer is rarer than in Western countries. The difference is not due to genetics – at least nor for the most part -- because as people migrate from Asia to the US, the breast cancer risk for their children and grandchildren matched that of other Americans.

Part of the difference relates to the fact that Japanese women are often thinner than Americans. Body fat produces estrogens -- female sex hormones that are linked to breast cancer. Many studies, including two very large ones, have shown that women with less body fat are less likely to develop postmenopausal breast cancer, compared with heavier women.

However, avoiding being overweight is not the only issue in cancer prevention. Here are four more steps that may help reduce risk:

Limit alcohol
A woman who has even one drink per day-- if it's every day -- has about a 10 percent higher risk of breast cancer, compared with women who avoid alcohol. The reason may relate to alcohol's tendency to disrupt the action of folic acid, a B vitamin with anticancer properties. It pays to keep alcohol use modest and intermittent.

Jan 1, 2013

January 1: The first day of the Gregorian year

Roman deity Janus
January 1 is the first day of the New Year according to the Gregorian calendar. With most countries using the Gregorian calendar as their main calendar, New Year's Day is the closest thing to being the world's only truly global public holiday, often celebrated with fireworks at the stroke of midnight as the New Year starts.

The choice of January 1 as the beginning of a new year dates back to the late 16th century when Pope Gregory designed the Liturgical Calendar.

January originally owes its name to the Roman deity Janus, the god of gates, doors, and beginnings, who had two faces, one looking forward and the other looking backward.

In the Middle Ages (the period in European history from the collapse of the Roman civilization in the 5th century AD to the beginning of the Renaissance -- variously interpreted as beginning in the 13th, 14th, or 15th century, depending on the region of Europe and on other factors) most European countries used the Julian calendar which observed New Year's Day on March 25th, called Annunciation Day -- an occasion celebrating angel Gabriel’s announcement to the Virgin Mary that she would conceive a Son of the Holy Spirit to be called Jesus (Luke 1:26–38).