Dec 28, 2014

Antibody

An antibody also known as immunoglobulin is a Y-shape protective protein produced by the immune system in response to the presence of a foreign substance, called an antigen. Antibodies recognize and latch onto antigens in order to remove them from the body. A wide range of substances are regarded by the body as antigens, including disease-causing organisms and toxic materials such as insect venom.

When an alien substance enters the body, the immune system is able to recognize it as foreign because molecules on the surface of the antigen differ from those found in the body. To eliminate the invader, the immune system calls on a number of mechanisms, including one of the most important — antibody production. Antibodies are produced by specialized white blood cells called B lymphocytes or B cells. When an antigen binds to the B-cell surface, it stimulates the B cell to divide and mature into a group of identical cells called a clone. The mature B cells, called plasma cells, secrete millions of antibodies into the bloodstream and lymphatic system.

Dec 21, 2014

Persia - One of the world’s first civilizations

Persia (which changed its name to Iran in 1935) was one of the world's first civilizations; it has evidence of Neolithic Aryan (peoples who spoke Indo-European languages) settlements from nearly ten thousand years ago. Persians are a non-Arab people who migrated from central Asia. According to National Geographic, "If you draw lines from the Mediterranean to Beijing or Beijing to Cairo or Paris to Delhi, they all pass through Iran, which straddles a region where East meets West. Over 26 centuries, a blending of the hemispheres has been going on here-trade, cultural interchange, friction -- with Iran smack in the middle."

The Elamites established the first known Persian dynasty in the third millennium BC. Another Aryan people, the Medes (the ancestors of the Kurds of today), created a unified empire in the northwestern part of that region around 625 BC. Cyrus the Great, who issued what some consider the world's first declaration of human rights, overthrew the Medes and established the Achaemenid Empire, expanding Persian control and influence from Egypt to India -- making it one of the largest empires in history. His descendants, Darius and his son Xerxes, invaded Greece but were defeated and expelled from Europe in 479 BC.

In the next century, Alexander the Great conquered Persia and ended the Achaemenid dynasty. After about a hundred years of Alexander's Seleucid Empire, the Parthian and Sassanid dynasties reestablished Persian rule until the Arab invasion in the seventh century AD. The Persians, the Kurds, the Turks, and others then converted to Islam. 
(Kee Malesky, ‘All Facts Considered – the essential library of inessential knowledge’)

Dec 14, 2014

Arterial stiffness


Arterial stiffness occurs as a consequence of age and arteriosclerosis. Age related stiffness occurs when the elastic fibres within the arterial wall (elastin) begin to fray due to mechanical stress. The two leading causes of death in the developed world, myocardial infarction and stroke, are both a direct consequence of atherosclerosis. Increased arterial stiffness is associated with an increased risk of cardiovascular events.

When the heart contracts it generates a pulse or energy wave that travels through the circulation. The speed of travel of this pulse wave (pulse wave velocity or PWV) is related to the stiffness of the arteries. 

(PWV) is a measure of arterial stiffness. It is easy to measure invasively and non-invasively in humans, is highly reproducible, has a strong correlation with cardiovascular events and all-cause mortality, and was recognized by the European Society of Hypertension as integral to the diagnosis and treatment of hypertension. 
(Wikipedia Encyclopedia)

Dec 7, 2014

Undernourished Worldwide -- 2014

Haiti: has the highest percentage of undernourished – 52%
India: has the highest number of undernourished – 191 Million
(Adapted from National Geographic)

Nov 30, 2014

History of Biology

The systematic approach to biology started with the Greek philosophers about 2,500 years ago. Aristotle (384-322 B.C.) is considered the "father of biology" for his classification of animals and for performing the first known biology experiments, dissecting plants and animals and studying the development of the chick in its egg. His student Theophrastus (ca. 372-286 B.C.) laid the foundation of botany, describing and classifying more than 500 plants and also describing the ways plants can germinate and grow. In Roman times, Lucretius (99-55 B.C.) proposed one of the earliest theories of evolution. But other than medical knowledge, biology made little progress until after the Middle Ages.

In the 15th and 16th centuries Europeans explored the Americas and some of the Pacific islands, and regular contact between Europe and southern Africa and eastern Asia was instituted. As a result European scholars were exposed to a great variety of plants and animals that were new to them. They responded with books describing and classifying both newfound and familiar plants and animals, starting as early as 1530. A few years later the first botanical gardens began to be established. When the scientific revolution of the 17th century began, scientists undertook more detailed experiments in biology. For example, Jan van Helmont (1579-1694) carefully measured the weight of soil in a tub as a willow grew there, establishing that the increase in mass of the willow was much greater than any diminution of mass of the soil.

Nov 23, 2014

The universe’s invisible web

Something out there holds swarms of galaxies together and keeps their stars from flying apart, but scientists still haven’t learned what this invisible substance is. Known as dark matter, it gathers to form a colossal cosmic scaffolding. Astronomers believe that galaxies formed at the densest points in this weblike structure, and the dark matter continues to hold them in place with its gravity. Its bulky presence can be detected by tracking stars on the outskirts of galaxies, which move at speeds that would be impossible if only visible matter – a galaxy’s other stars and gas – were pulling them. Astronomers have also mapped this unseen substance with the help of an effect predicted by Einstein’s general relativity; Dark matter’s gravity wrinkles space-time, bending light rays as they pass. Such measurements indicate that dark matter could make up 90 percent of the universe’s total mass. These days, cosmologists are searching for the identity of dark matter, trying to detect the elusive substance responsible for arranging everything we see in the sky. 
(National Geographic, May 2005)

Nov 16, 2014

Healthy foods, healthy arteries: is there a connection?

What you eat can help keep your heart and arteries healthy — or lead to excessive weight, high blood   pressure, and high blood cholesterol — three key factors that increase the risk of developing cardiovascular disease, according to the National Heart, Lung, and Blood Institute. Based on the best available scientific evidence, the American Heart Association (AHA) recommends a diet that includes a variety of fruits, vegetables, and grains, while limiting consumption of saturated fat and sodium.  

Fruits and vegetables have lots of antioxidants such as vitamin C and vitamin A that neutralize free radicals and may prevent oxidation in the arteries, dietary experts say. Fruits and vegetables also contain plenty of soluble fiber, a substance that has been shown to reduce blood cholesterol levels, which is healthy for the endothelium.  

Breads, cereals, and other grain foods, which provide complex carbohydrates, vitamins, minerals, and fiber, are associated with a decreased risk of cardiovascular disease, according to the AHA Dietary Guidelines. However, some studies suggest eating less sugar, breads, and other simple and complex carbohydrates can lower blood insulin levels and decrease body fat and weight — three factors that are linked to an increased risk of heart disease and stroke. In recent years, a number of dietary recommendations based on these findings have become popular and are currently catching   the public’s awareness. While contentious, these are important issues and long-term studies are required to determine the risks and benefits of such diets, Dr. Lakatta says. 

Nov 9, 2014

Viruses on other life-bearing planets

It has been proposed that viruses are likely to be encountered on other life-bearing planets. Efforts to discover current or past life on Mars is an active area of research. On 24 January 2014, NASA reported that current studies on the planet Mars by the Curiosity and Opportunity rovers will now be searching for evidence of ancient life, including a biosphere based on autotrophic, chemotrophic and/or chemolithoautotrophic microorganisms, as well as ancient water, including fluvio-lacustrine environments (plains related to ancient rivers or lakes) that may have been habitable. The search for evidence of habitability, taphonomy (related to fossils), and organic carbon on the planet Mars is now a primary NASA objective. 
(Wikipedia)

Nov 2, 2014

Ancient Egypt - political history

Ancient Egypt was one of the world's great early civilizations, a nation and culture that dominated northern Africa for nearly 3,000 years and saw hundreds of kings rule over some 30 dynasties. Factors like climate and geography, together with innovative leadership and bureaucratic organization, made possible a legacy that continues to fascinate scholars and amateurs alike: the pyramids, with their staggering scale and mathematical ingenuity; mummies and tombs that provide modern researchers with an enormous body of material to examine; and innumerable carvings of pictures and writing, made decipherable by the Rosetta Stone. The unusually high status of women, the worship of gods of sun and nature, and a fixation on the afterlife are some of the themes that make ancient Egypt alluring to modem students.

As the Ganges was to India and the Yangtze to China, the Nile River was the mother of Egyptian civilization, spurring the rise of agriculture, trade, and one of the most successful societies in the ancient world. Flowing northward out of Burundi into Lake Victoria then through Uganda and Sudan on its way to the Mediterranean Sea, the Nile is the longest river in the world, traversing more than 4,000 miles of the African continent.

Oct 26, 2014

Keeping Your Arteries Healthy

The well-being of your arteries depends on a healthy endothelium, the inner lining of your blood vessels. “Endothelial cells are the prima donnas within the blood vessels. They control almost every activity that occurs in the vessels, and they’re fundamentally altered with age,” Dr. Lakatta says. “People who maintain a healthy endothelium as they get older and those who make an effort to do things that promote the repair of injured endothelium can reduce the risk of heart attacks and strokes caused by atherosclerosis or hypertension.”

Although scientists still have much to learn about the endothelium and what can be done to keep it healthy, a number of studies suggest that certain modifiable risk factors can have an important impact on the cardiovascular system. For instance, regular moderate exercise, such as running, walking, or swimming can reduce body fat, increase lean muscle mass, decrease blood pressure, increase HDL cholesterol (the “good” cholesterol) levels, and lessen the extent of arterial stiffening. All of these exercise-induced changes can have a positive influence on endothelial cells.

Oct 18, 2014

Astrobiology

Astrobiology is the study of the origin, evolution, distribution, and future of life in the universe: extraterrestrial life and life on Earth. This interdisciplinary field encompasses the search for habitable environments in our Solar System and habitable planets outside our Solar System, the search for evidence of prebiotic chemistry, laboratory and field research into the origins and early evolution of life on Earth, and studies of the potential for life to adapt to challenges on Earth and in outer space. Astrobiology addresses the question of whether life exists beyond Earth, and how humans can detect it if it does. (The term exobiology is similar but more specific — it covers the search for life beyond Earth, and the effects of extraterrestrial environments on living things.)

Astrobiology makes use of physics, chemistry, astronomy, biology, molecular biology, ecology, planetary science, geography, and geology to investigate the possibility of life on other worlds and help recognize biospheres that might be different from the biosphere on Earth. Astrobiology concerns itself with interpretation of existing scientific data; given more detailed and reliable data from other parts of the universe, the roots of astrobiology itself — physics, chemistry and biology — may have their theoretical bases challenged. Although speculation is entertained to give context, astrobiology concerns itself primarily with hypotheses that fit firmly into existing scientific theories. 
(Wikipedia Encyclopedia)

Oct 11, 2014

Consciousness

Consciousness is defined in the dictionary as: 1. the state of being conscious; awareness of one's own existence, sensations, thoughts, surroundings, etc.  2. the thoughts and feelings, collectively, of an individual or of an aggregate of people: the moral consciousness of a nation.3. full activity of the mind and senses, as in waking life: to regain consciousness after fainting. 4. awareness of something for what it is; internal knowledge: consciousness of wrongdoing. 5. concern, interest, or acute awareness: class consciousness. 6. the mental activity of which a person is aware as contrasted with unconscious mental processes. 7. Philosophy. the mind or the mental faculties as characterized by thought, feelings, and volition. Idioms: raise one's consciousness: to increase one's awareness and understanding of one's own needs, behavior, attitudes, etc., especially as a member of a particular social or political group.

Psychologists define consciousness as the quality or state of awareness, or, of being aware of an external object or something within oneself. The English philosopher John Locke defined it as “the perception of what passes in a man's own mind.” It is also defined as: sentience, awareness, subjectivity, the ability to experience or to feel, wakefulness, having a sense of selfhood, and the executive control system of the mind. Despite the difficulty in definition, many philosophers believe that there is a broadly shared underlying intuition about what consciousness is.  As Max Velmans and Susan Schneider wrote in The Blackwell Companion to Consciousness: "Anything that we are aware of at a given moment forms part of our consciousness, making conscious experience at once the most familiar and most mysterious aspect of our lives."

Oct 4, 2014

Eye Anatomy

The eye comprises three main outer layers and an inner chamber, which is filled with a thick, clear fluid, known as vitreous humor. ('The Human Brain Book', by Rita Carter)

Sep 27, 2014

Oxygen supply to human brain

The arteriograph shows arteries carrying oxygen-rich blood to the brain. The arrangement of the arteries allows blood to be supplied by another route if one of the pathways is blocked. ('The Human Brain Book' by Rita Carter)

Sep 13, 2014

Region with the fastest growing population in the world

No region of the world is growing faster than sub-Saharan Africa. Today's population of 926 million may hit 2.2 billion by 2050. (National Geographic, July 2014)

Sep 6, 2014

Momentum

The boulder, unfortunately has more
momentum than the runner
Momentum is the mass of an object multiplied by its velocity. The momentum of an object depends on its mass and velocity. This means that an object's momentum changes as it accelerates. Momentum can be transferred between objects. When a moving ball collides with a stationary one, for example, the first ball transfers some of its momentum to the second ball. The total momentum of the two balls is the same as the first ball's momentum before the collision. This is called the principle of conservation of momentum. 
(Dictionary of Science, by Neil Ardley) 

Aug 23, 2014

Arteries, veins, and capillaries in human body

Three types of blood vessels form a complex network of tubes throughout the body. Arteries carry blood away from the heart, and veins carry it toward the heart. Capillaries are the tiny links between the arteries and the veins where oxygen and nutrients diffuse to body tissues. The inner layer of blood vessels is lined with endothelial cells that create a smooth passage for the transit of blood. This inner layer is surrounded by connective tissue and smooth muscle that enable the blood vessel to expand or contract. Blood vessels expand during exercise to meet the increased demand for blood and to cool the body. Blood vessels contract after an injury to reduce bleeding and also to conserve body heat.

Arteries have thicker walls than veins to withstand the pressure of blood being pumped from the heart. Blood in the veins is at a lower pressure, so veins have one-way valves to prevent blood from flowing backwards away from the heart. Capillaries, the smallest of blood vessels, are only visible by microscope—ten capillaries lying side by side are barely as thick as a human hair. If all the arteries, veins, and capillaries in the human body were placed end to end, the total length would equal more than 100,000 km (more than 60,000 miles—they could stretch around the earth nearly two and a half times.

The arteries, veins, and capillaries are divided into two systems of circulation: systemic and pulmonary. The systemic circulation carries oxygenated blood from the heart to all the tissues in the body except the lungs and returns deoxygenated blood carrying waste products, such as carbon dioxide, back to the heart. The pulmonary circulation carries this spent blood from the heart to the lungs. In the lungs, the blood releases its carbon dioxide and absorbs oxygen. The oxygenated blood then returns to the heart before transferring to the systemic circulation. 
(Encarta Encyclopedia)

Aug 16, 2014

There could be as many as 40 billion Earth-sized planets orbiting in the habitable zones of sun-like stars and red dwarf stars within the Milky Way Galaxy

Earth is the only place in the universe known to harbor life. However, recent advances in planetary science have changed fundamental assumptions about the possibility of life in the universe, raising the estimates of habitable zones around other stars, along with the discovery of hundreds of extrasolar planets and new insights into the extreme habitats here on Earth, suggesting that there may be many more habitable places in the universe than considered possible until very recently. On 4 November 2013, astronomers reported, based on Kepler space mission data, that there could be as many as 40 billion Earth-sized planets orbiting in the habitable zones of sun-like stars and red dwarf stars within the Milky Way Galaxy -- 11 billion of these estimated planets may be orbiting sun-like stars. The nearest such planet may be 12 light-years away, according to the scientists. 
(Wikipedia Encyclopedia)

Aug 9, 2014

English ranks third among the world's most spoken languages

As of 2010, Mandarin was the mother language of 14.4% of the world’s population, Spanish 6.15%, and English 5.43%.

Although English ranks only third among the world's most spoken languages, it is on its way to becoming the first truly global language - used throughout the world as the language of commerce, diplomacy, and science. English is the mother tongue for some 450 million people, and a further 1.5 billion people use it as a second language to some degree. Beginning in the 17th century, the language spread throughout the British Empire to the Americas, Africa, India, and Oceana. Today 70 countries designate English as an official language (although it does not have that status in the United States), and it is an official language of the United Nations, the European Union, Nafta, NATO, and the Organization of American States. 
(Adapted from ‘The New York Times ‘Smarter by Sunday – 52 Weekends of Essential Knowledge for the Curious Mind’ and Wikipedia)

Aug 2, 2014

Kilauea – the world’s most active volcanic crater

Kilauea is located on central Hawaii Island, Hawaii. It is situated on the southeastern slope of the great volcanic mountain Mauna Loa, at an elevation of 1,247 m (4,090 ft) above sea level, which is more than 3000 m (almost 10,000 ft) below the summit of the mountain. The crater, which forms a great cavity in the side of the mountain, has an area of about 10 sq km (about 4 sq mi); the walls of the crater are from 60 to 210 m (about 200 to 700 ft) high. Except for occasional lava flows across the floor of the crater, volcanic activity in recent times has been restricted to an inner crater called Halemaumau, which measures more than 900 m (about 3000 ft) across and has a depth of about 400 m (about 1300 ft).

Jul 26, 2014

Cardiovascular System – its functions and components

Circulatory system, or cardiovascular system, in humans, includes the combined functions of the heart, blood, and blood vessels. It transports oxygen and nutrients to organs and tissues throughout the body and carry away waste products. Among its vital functions, the circulatory system increases the flow of blood to meet increased energy demands during exercise and regulates body temperature. In addition, when foreign substances or organisms invade the body, the circulatory system swiftly conveys disease-fighting elements of the immune system, such as white blood cells and antibodies, to regions under attack. Also, in the case of injury or bleeding, the circulatory system sends clotting cells and proteins to the affected site, which quickly stop bleeding and promote healing.

The heart, blood, and blood vessels are the three structural elements that make up the circulatory system. The heart is the engine of the circulatory system. It is divided into four chambers: the right atrium, the right ventricle, the left atrium, and the left ventricle. The walls of these chambers are made of a special muscle called myocardium, which contracts continuously and rhythmically to pump blood. The pumping action of the heart occurs in two stages for each heart beat: diastole, when the heart is at rest; and systole, when the heart contracts to pump deoxygenated blood toward the lungs and oxygenated blood to the body. During each heartbeat, typically about 60 to 90 ml (about 2 to 3 oz) of blood are pumped out of the heart. If the heart stops pumping, death usually occurs within four to five minutes.

Blood consists of three types of cells: oxygen-bearing red blood cells, disease-fighting white blood cells, and blood-clotting platelets, all of which are carried through blood vessels in a liquid called plasma. Plasma is yellowish and consists of water, salts, proteins, vitamins, minerals, hormones, dissolved gases, and fats. 
(Encarta Encyclopedia)

Jul 19, 2014

The combined length of arteries, veins and capillaries in a human body

If all the arteries, veins, and capillaries in the human body were placed end to end, the total length would equal more than 100,000 km (more than 60,000 miles — they could stretch around the earth nearly two and a half times. 
(Encarta Encyclopedia)

Jul 12, 2014

Mental Energy - Feel the Flow of Enthusiasm

Call it drive, vigor, enthusiasm, or get-up-and-go. Call it zest, gusto, razzmatazz, or just plain oomph. It's what gives you ambition, puts a sparkle in your eye, and fills your day with spirit and glow. It's what makes you jump out of bed in the morning, fill your lungs with air, and charge out the front door ready to take on the entire world.

We're talking about the greatest form of energy on earth. It doesn't come from oil, coal, or natural gas. It comes from your mind.

When the energy is flowing, really flowing, nothing, but nothing, can stop you. You feel powerful, brilliant, and tremendously alive. You feel like King Kong with a Ph.D. But, when the energy stops flowing-ugh. You feel like Dr. Kong after he fell from the Empire State Building.

If you're like most people, your energy flow can get a little erratic from time to time, and you'd like to do something about it. You'd like to boost the wattage and assure yourself of a steady, never-ending supply of power.  Well? Don't just lie there like a big ape sprawled out on a Manhattan sidewalk! Read the sections below under the following headings:

A. The Brain in the Energetic Lane
B. Energy Is a State of Mind
C. A Deeper Sense of Self       
D. The Will to Succeed
E. Of Body and Mind

Jul 5, 2014

The Eightfold Buddhist Path -- freeing oneself from suffering rooted in ignorance

Buddha’s first teaching to his disciples is reported to have been the “First Turning of the Wheel of Dharma.” The Sanskrit word dharma has many shades of meaning. In its original Vedic context, it meant "duty" in the sense of social obligation, such as the obligation one feels as a member of a particular caste. In a Buddhist context, however, the meaning of dharma is closer to "truth" or "reality" (or even law," as in law of nature).

The Buddha's first teaching asserted four "truths about the nature of reality. The first was that ordinary life is characterized by suffering -- physical suffering, emotional suffering, and a sort of angst inherent in day-to-day existence. The second truth was that the cause of this suffering is the desire that follows from all beings' ignorance of the true nature of reality. The third truth was that it is possible to attain a state of being in which suffering is extinguished. The fourth truth concerned the Eightfold Path leading to that state. 

Jun 28, 2014

Alternative technologies concerning energy

What makes a technology conventional is its widespread use, and what makes it widespread is its low cost and convenience. Therefore, almost by definition, alternative technologies cost more than conventional ones, at least in terms of the price paid by the consumer. For example, among alternative technologies, wind power has come the closest to competing with conventional fossil fuels, yet it still costs about 50 percent more than coal-generated electricity. If, however, one takes into account the hidden costs of conventional energy and the noneconomic benefits of alternative technologies, then the equation changes.

Growing awareness of the environmental costs of conventional energy has led to increased demand for cleaner energy. Global warming, in particular, has altered the way many people think about the energy they consume - which, in turn, has begun to reshape the economic relationship between energy producers and consumers. As more and more consumers sign up for green energy programs and buy hybrid cars (both of which carry additional costs), energy companies are reconsidering whether the conventional wisdom of cheap, convenient, and plentiful above all still applies. Skeptics argue that the demand for cheap, large-scale energy resources will continue to trump the relatively new consumer preference for clean, renewable alternatives. On the other hand, if the era of cheap petroleum-based energy is indeed ending -- as shrinking petroleum reserves and rising gasoline prices indicate -- then one may not even have to factor in the hidden costs and benefits for today's alternative technologies to become tomorrow's conventional resources.

Jun 21, 2014

Slide Rule

A mechanical device formerly used by engineers and scientists for rapid and approximate multiplication, division, extraction of roots, raising to powers, and other simple computations. The slide rule has been almost totally superseded by the small hand-held electronic calculator. The principle of the slide rule is the translation of all computations to equivalent additions or subtractions that can be carried out on a set of scales sliding over each other. Thus, two uniformly graduated marked scales can be used for addition or subtraction, multiplication, division, powers, and logarithms. Other scales, such as for sine, cosine, and tangent, and logarithm and for calculations involving p (pi) are also found on the usual rectilinear slide rule. A glass runner or cursor with a finely engraved vertical line is provided for easier alignment of the scales.

The computational accuracy possible depends on the size of the slide rule and on the care with which the scales are printed. The commonly used 10-in. slide rule permits multiplications and divisions to be made with an accuracy of about 1/10th percent, which suffices for many engineering calculations. Both the rectilinear and the less commonly used circular slide rule were invented by the English mathematician William Oughtred shortly after the discovery of logarithms. Various special slide rules have been devised for the solution of widely applicable engineering formulas, or for business calculations, such as the determination of interest, compound interest accumulation, and depreciation. 
(Adapted from Encarta Encyclopedia)

Jun 14, 2014

Renewable Energy – wind and solar

The first wind turbines actually predate the electric power grid, with two near-simultaneous developments in the late 19th century. The Scottish engineer James Blyth constructed a 33- foot electricity-generating wind turbine in 1887, and the following year the American engineer Charles Brush built the first automatic wind turbine, wiring the first electrically powered building in Ohio. Likewise, throughout the 1800s, scientists were experimenting in the various technologies that make photovoltaic solar panels possible; the first solar powered steam engine was built in 1861.

Since then, the use of wind and solar power has grown steadily, with a surge in recent years. Wind power, while, still providing a small total percentage of U.S. power, is growing much more rapidly than solar power. From 1990 to 2008, U.S. production of wind power grew from 300 trillion Btu annually to 510 trillion; solar has increased modestly from 60 trillion BN to 90 trillion. Shipments of solar photovoltaic cells and modules continues to expand, however. From 2000 to 2008, U.S. manufacturers increased shipments of photovoltaic components from 20,000 modules in 2000 to 524,000 modules in 2008. Production of hydroelectric power, the nation's largest renewable energy source, has remained more or less steady since 1990, declining somewhat from 3.05 quadrillion Btu to 2.45 quadrillion Btu in 2008.

Jun 7, 2014

Environmentalism in the United States

The first federal environmental act was the establishment of Yellowstone National Park in March 1872 in the territories of Montana and Wyoming. Instead of promoting the land for development, Congress and President Ulysses S. Grant declared that it should be preserved "as a public park or pleasuring ground for the benefit and enjoyment of the people." As the first such preserve in the world, Yellowstone inaugurated an international national park movement that currently includes some 1,200 parks or preserves in 100 countries, including 391 in the United States.

The Scottish naturalist John Muir became an early advocate for preservation after his travels and scientific work convinced him that some natural areas need protection from human exploitation. Muir founded the Sierra Club in 1892 to that end and urged President Theodore Roosevelt to join the cause. Roosevelt, himself known as an ardent outdoorsman, eventually dedicated more than 150 million acres to national parks and forests, and founded the US. Forest Service, which manages forests for water and timber resources while protecting them for wildlife and recreation. The first chief of the Forest Service, Gifford Pinchot, promoted a "wise use" strategy of wilderness management that proposed, in contrast to Muir, that nature could be safely commercialized.

May 31, 2014

The adverse effect of environmental changes on biodiversity

While pollution and global warming have obvious effects on human health, ecologists also define environmental health according to biodiversity. Biodiversity measures the variety of living things and their interactions on three levels: genetics, species, and ecosystem diversity. The number of known species - characterized by scientific analysis and description - is more than 1.7 million, including nearly 1 million species of insects, about 14,000 species of amphibians and reptiles, and 5,400 mammalian species. However, there are many other species living on Earth, including trillions of microscopic organisms like bacteria. These species interact to form sustainable check-and balance networks like the food chain.

Human population growth, deforestation, pollution, and global warming have caused a rapid loss of biodiversity. Today's extinction rate is estimated to be 1,000 to 10,000 times higher than the natural rate, and some scientists believe we are in the midst of a mass extinction. For example, the International Union for Conservation of Nature reported in 2008 that 30 percent of amphibian species are critically endangered or vulnerable. This number increased 2,588 percent between 1996 (18 species) and 2010 (484 species). (Adapted from ‘The New York Times ‘Smarter by Sunday – 52 Weekends of Essential Knowledge for the Curious Mind’)

May 24, 2014

The world's first designated wilderness

In 1924, due to Aldo Leopold's (an American environmentalist) efforts as a Forest Service employee, the Gila National Forest in New Mexico became the world's first designated wilderness. This designation allows travel only by foot or horseback and bans any commercial activity except grazing in order to protect the usefulness of the wilderness for cleaning air and reducing climate change, as well as providing clean water, wildlife habitat, and natural recreational experiences. (Adapted from ‘The New York Times ‘Smarter by Sunday – 52 Weekends of Essential Knowledge for the Curious Mind’)

May 17, 2014

Number of known species

The number of known species - characterized by scientific analysis and description - is more than 1.7 million, including nearly 1 million species of insects, about 14,000 species of amphibians and reptiles, and 5,400 mammalian species. It is estimated that there are also trillions of microscopic organisms like bacteria. (Adapted from 'The New York Times ‘Smarter by Sunday – 52 Weekends of Essential Knowledge for the Curious Mind’) 

May 10, 2014

Air & Liquid Air

Air is the mixture of gases that surrounds the Earth. Air contains mainly the gases nitrogen and oxygen, with small amounts of argon and other noble gases and carbon dioxide. The proportions of these gases in air are the same anywhere around the world. Air also contains water vapor, dust, and polluting gases, which vary in amount from place to place. When air is cooled to -328°F (-200°C), most of the gases condense, forming a blue liquid called liquid air. (Dictionary of Science, by Neil Ardley)

May 3, 2014

America’s Independence Day

Independence Day, commonly known as the Fourth of July, is a federal holiday in the United States commemorating the adoption of the Declaration of Independence on July 4, 1776, declaring independence from the Kingdom of Great Britain (now officially known as the United Kingdom). Independence Day is commonly associated with fireworks, parades, barbecues, carnivals, fairs, picnics, concerts, baseball games, family reunions, and political speeches and ceremonies, in addition to various other public and private events celebrating the history, government, and traditions of the United States. Independence Day is the National Day of the United States.

During the American Revolution, the legal separation of the Thirteen Colonies from Great Britain occurred on July 2, 1776, when the Second Continental Congress voted to approve a resolution of independence that had been proposed in June by Richard Henry Leeof Virginia declaring the United States independent from Great Britain. After voting for independence, Congress turned its attention to the Declaration of Independence, a statement explaining this decision, which had been prepared by a Committee of Five, with Thomas Jefferson as its principal author. Congress debated and revised the wording of the Declaration, finally approving it on July 4. A day earlier, John Adams had written to his wife Abigail:

The second day of July, 1776, will be the most memorable epoch in the history of America. I am apt to believe that it will be celebrated by succeeding generations as the great anniversary festival. It ought to be commemorated as the day of deliverance, by solemn acts of devotion to God Almighty. It ought to be solemnized with pomp and parade, with shows, games, sports, guns, bells, bonfires, and illuminations, from one end of this continent to the other, from this time forward forever more.

Apr 26, 2014

Ben-Gurion -- Israel's "founding father" and first Prime Minister

Born David Gruen in Poland, Ben-Gurion became committed to Zionism, the movement to settle and unite Jews in Palestine, under the influence of his father and grandfather. He studied in Warsaw, where he joined Po’alei Zion (Workers of Zion), a socialist workers party. Ben-Gurion saw Zionism as a practical idea to be carried out by Jewish immigration to Palestine and building the land through collective labor. In 1906 he moved to Jaffa, Palestine (now part of Tel Aviv-Yafo, Israel), and worked as a farmer. There he was elected to the central committee of Po’alei Zion and began organizing workers into unions. In 1910 he moved to Jerusalem and joined the editorial staff of a new Hebrew-language newspaper, Ahdut (Unity), publishing articles under the name Ben-Gurion (Hebrew for "son of the young lion"). He enrolled at the University of Constantinople in present-day Turkey in 1912 and earned a law degree in 1914. He then returned to Palestine and resumed his work as a union organizer, but in 1915 he traveled to the United States after he and thousands of other Zionists were exiled by the Ottoman Empire authorities who controlled Palestine.

Apr 19, 2014

The Great Wall of China

Great Wall (China), popular name for a semi-legendary wall built to protect China’s northern border in the 3rd century BC, and for impressive stone and earthen fortifications built along a different northern border in the 15th and 16th centuries AD, long after the ancient structure had disappeared. Ruins of the later wall are found today along former border areas from Bo Hai (a gulf of the Yellow Sea) in the east to Gansu Province in the west. The Great Wall is visited often near Beijing, at a site called Ju-yong-guan, and at its eastern and western extremes.

Perhaps China's best known monument—even national symbol—the Great Wall is not what most people imagine it to be. The existing wall is not several thousand years old, nor is it, as is widely asserted, visible from outer space (astronauts confirm this). Indeed, the Great Wall is not even a single, continuous structure. Rather, it consists of a network of walls and towers that leaves the frontier open in places.

Apr 12, 2014

Colonial America: 1492-1763

European nations came to the Americas to increase their wealth and broaden their influence over world affairs. The Spanish were among the first Europeans to explore the New World and the first to settle in what is now the United States.

By 1650, however, England had established a dominant presence on the Atlantic coast. The first colony was founded at Jamestown, Virginia, in 1607. Many of the people who settled in the New World came to escape religious persecution. The Pilgrims, founders of Plymouth, Massachusetts, arrived in 1620. In both Virginia and Massachusetts, the colonists flourished with some assistance from Native Americans. New World grains such as corn kept the colonists from starving while, in Virginia, tobacco provided a valuable cash crop. By the early 1700s enslaved Africans made up a growing percentage of the colonial population. By 1770, more than 2 million people lived and worked in Great Britain's 13 North American colonies ( http://www.americaslibrary.gov/)

Apr 5, 2014

September 30, 1882: The World's First Hydroelectric Power Plant Began Operation

 When you look at rushing waterfalls and rivers, you may not immediately think of electricity. But hydroelectric (water-powered) power plants are responsible for lighting many of our homes and neighborhoods. On September 30, 1882, the world's first hydroelectric power plant began operation on the Fox River in Appleton, Wisconsin. The plant, later named the Appleton Edison Light Company, was initiated by Appleton paper manufacturer H.J. Rogers, who had been inspired by Thomas Edison's plans for an electricity-producing station in New York. 

Unlike Edison's New York plant which used steam power to drive its generators, the Appleton plant used the natural energy of the Fox River. When the plant opened, it produced enough electricity to light Rogers's home, the plant itself, and a nearby building. Hydroelectric power plants of today generate a lot more electricity. By the early 20th century, these plants produced a significant portion of the country's electric energy. The cheap electricity provided by the plants spurred industrial growth in many regions of the country. To get even more power out of the flowing water, the government started building dams. 

In 1933, the U.S. government established the Tennessee Valley Authority (TVA), which introduced hydroelectric power plants to the South's troubled Tennessee River Valley. The TVA built dams, managed flood control and soil conservation programs, and more. It greatly boosted the region's economy. And this development happened in other places as well. Soon, people across the country were enjoying electricity in homes, schools, and offices, reading by electric lamp instead of candlelight or kerosene. New electricity-powered technologies entered American homes, including electric refrigerators and stoves, radios, televisions, and can openers. Today, people take electricity for granted, not able to imagine life without it. (http://www.americaslibrary.gov/)

Mar 29, 2014

Sources of Energy – until 1859 when the first oil well in the United States was drilled in Pennsylvania

When the steam engine was invented at the beginning of the 18th century, most sources of fuel worldwide were the same as they had been for centuries: wood for cooking, oil for lighting, coal for heating and industry. The advent of commercially successful steam power in 1712 allowed for machinery and engines that were larger and more capable than any machines had ever been, catalyzing the dramatic changes of the Industrial Revolution. During the 19th century, continuous improvements to steam engine design transformed factories and built railroads across Europe and the Americas. Both inventors and engineers knew, however, that steam power had significant limitations. Steam must be generated by burning fuel, usually coal: and steam engines were large and bulky to allow for a furnace. The first steam-powered locomotive, invented in 1804 by the English engineer Richard Trevethick, was so heavy it broke the rails it rode on. From the earliest days of the Industrial Revolution, engineers looked for alternatives to steam that would allow for lighter, more powerful engines.

Internal combustion provided one such alternative. For centuries, inventors had imagined and tinkered with internal combustion engines; the medieval Arab scholar Al-Jazari described twin-cylinder reciprocating pistons in 1206, and Leonardo da Vinci sketched compressionless engines in 1509. The modem combustion engine was the British inventor Robert Street's 1794 model, which used exploding gas to drive the pistons.

Mar 22, 2014

Mar 15, 2014

A black hole is born …

The sun is of only average mass, starwise, and after burning through the last of its hydrogen fuel in about five billion years, its outer layers will drift away, and the core will eventually compact to become what's known as a white dwarf, an Earth-size ember of the cosmos.

For a star ten times as big as the sun, death is far more dramatic. The outer layers are blasted into space in a supernova explosion that, for a couple of weeks, is one of the brightest objects in the universe. The core, meanwhile, is squeezed by gravity into a neutron star, a spinning ball bearing a dozen miles in diameter. A sugar-cube-size fragment of a neutron star would weigh a billion tons on Earth; a neutron star's gravitational pull is so severe that if you were to drop a marshmallow on it, the impact would generate as much energy as an atom bomb.

But this is nothing compared with the death throes of a star some 20 times the mass of the sun. Detonate a Hiroshima-like bomb every millisecond for the entire life of the universe, and you would still fall short of the energy released in the final moments of a giant-star collapse. The star's core plunges inward. Temperatures reach 100 billion degrees. The crushing force of gravity is unstoppable. Hunks of iron bigger than Mount Everest are compacted almost instantly into grains of sand. Atoms are shattered into electrons, protons, neutrons. Those minute pieces are pulped into quarks and leptons and gluons. And so on, tinier and tinier, denser and denser, until. ..

Until no one knows. When trying to explain such a momentous phenomenon, the two major theories governing the workings of the universe – general relativity and quantum mechanics – both go haywire, like dials on an airplane wildly rotating during a tailspin.

The star has become a black hole. (Michael Finkel, National Geographic)

Mar 2, 2014

Water bears – micro-animals theoretically capable of surviving a space journey without protection

Tardigrades (also known as water bears or moss piglets) are water-dwelling, segmented micro-animals, with eight legs. They were first described by the German pastor J.A.E. Goeze in 1773. The name Tardigrada (meaning "slow stepper") was given three years later by the Italian biologist Lazzaro Spallanzani.

Usually, tardigrades are about 0.5 mm (0.020 in) long when they are fully grown. They are short and plump with four pairs of legs, each with four to eight claws also known as "disks". The animals are prevalent in mosses and lichens and feed on plant cells, algae, and small invertebrates. When collected, they may be viewed under a very-low-power microscope, making them accessible to students and amateur scientists. Their mouths have sharp pointy objects, called stylets. They use their stylets to cut into moss leaves or algae, their main foods. Then they suck the juices from the plant. Tardigrades live worldwide in moist land habitats, along rocky shorelines, and on the bottoms of streams, lakes, and oceans.

Feb 23, 2014

The Four Gospels

A gospel (from Old English, gōd spell "good news") is a writing that describes the life of Jesus. The word is primarily used to refer to the four canonical gospels: the Gospel of Matthew, Gospel of Mark, Gospel of Luke and Gospel of John, probably written between AD 65 and 80. They appear to have been originally untitled; they were quoted anonymously in the first half of the second century (i.e. 100 - 150) but the names by which they are currently known appear suddenly around the year 180. The first canonical gospel written is thought by most scholars to be Mark (c 65-70). (Wikipedia, the online free encyclopedia) 

Feb 16, 2014

Dolphins can stay constantly alert for more than two weeks

Dolphin (aquatic mammal), fast-swimming mammal belonging to the order Cetacea, which also includes whales and porpoises. Sleek and powerful swimmers, dolphins are found in seas throughout the world; some inhabit freshwater rivers and lakes. Characteristic features of most dolphins are long snouts with rows of sharp teeth, and rounded foreheads with a nostril on top, known as the blowhole.

There are at least 40 species of dolphins. Dolphins resemble fish in many ways, but they exhibit a number of true mammalian characteristics: They are warm-blooded, breathe air, and nurse their young on milk. Dolphins and porpoises have a similar appearance, but dolphins can be distinguished from porpoises by their more prominent snouts and conical teeth. Porpoises have blunt snouts, chisel-shaped teeth, and a stouter body than dolphins.

Sailors have long considered the presence of dolphins cruising alongside the bows of ships as a good omen and a promise of fair weather. Dolphins also figure prominently in folklore, often appearing in works of art, on coins and currency, and on stamps. Ancient Greek coins depicted the son of Poseidon seated on a dolphin, and the ancient Roman author Pliny the Elder wrote a story of a dolphin that carried a poor man's son to school each day. Many classical writers described how dolphins harnessed to chariots helped maidens in distress. A dolphin was on the coat of arms of the dauphin, the title given the eldest son and heir of the king of France.

Feb 9, 2014

Some interesting tidbits about various States of the United States

  • Alabama: Was the first state to have 9-1-1, started 1968.
  • Alaska: One out of every 64 people has a pilot's license. 
  • Arizona: Is the only state in the continental U.S. that does not follow Daylight Savings Time. 
  • Arkansas: Has the only active diamond mine in the U.S. 
  • California: Its economy is so large that if it were a country, it would rank seventh in the entire world. 
  • Colorado: In 1976 it became the only state to turn down the Olympics. 
  • Connecticut: The Frisbee was invented here at Yale University 
  • Delaware: Has more scientists and engineers than any other state. 
  • Florida: At 874.3 square miles, Jacksonville is the largest city in the U.S. 
  • Georgia: It was here, in 1886, that pharmacist John Pemberton made the first vat of Coca-Cola....interesting! 
  • Hawaii: Hawaiians live, on average, five years longer than residents of any other state. 
  • Idaho: TV was invented in Rigby, Idaho, in 1922. 
  • Illinois: Has a Governor in jail, one pending jail, and is the most corrupt state in the union! 

Feb 1, 2014

Early Music -- during ancient Greek and Roman empires (500 B.C. to 300 A.D.)

The first European music is that of the ancient Greeks and Romans, dating from roughly 500 B.C. to A.D. 3OO. Fewer than a dozen examples of Greek music from this period, written in an alphabetical notation, survive. Ancient Greek philosophers believed that music originated from the god Apollo, as well as from the mythological musician Orpheus and other divinities. They also believed that music reflected in microcosm the laws of harmony that rule the universe, and that music influenced human thought and actions.

The Greek philosopher Pythagoras (ca. 580 B.C.-ca. 500 B.C.) discovered the mathematical relationships between specific frequencies and musical inrervals, using a single-string instrument (called a monochord) to produce the various intervals. For example, two notes whose frequencies form a ratio of 2:1 sound one octave apart; a ratio of 3:2 forms an interval of a fifth, and a ratio of 4:3 forms a fourth. These basic intervals combine to create the modes and scales on which all Western melodies and harmony are based.

Jan 26, 2014

How many hairs does the average person have on his or her head and how much does human hair grow in a year?

The amount of hair covering varies from one individual to another. An average person has about 100,000 hairs on their scalp. Most redheads have about 90,000 hairs, blonds have about 140,000, and brunettes fall in between these two figures. Most people shed between 50 to 100 hairs daily. Each hair grows about 5 inches (12.7 centimeters) every year. (The Handy Science Answer Book, compiled by the Science and Technology department of the Carnegie Library of Pittsburgh)

Jan 20, 2014

Can a person get a suntan through a window?

No. The ultraviolet radiation that causes suntan does not pass through glass. A tan is the skin 's natural defense against these harmful sun rays. Pigment cells in the lower skin level make more pigment and melanin to absorb the ultraviolet rays. As the pigment spreads into the top layer of the skin, it becomes darker. (The Handy Science Answer Book, compiled by the Science and Technology department of the Carnegie Library of Pittsburgh)

Jan 15, 2014

The original meaning of the word “scapegoat”

As described in Leviticus 16:1-27, part of a Hebrew ritual on the Day of Atonement involved the presentation of two male goats at the altar of the tabernacle. After lots were cast, one goat was sacrificed to the Lord; the other, the  scapegoat’, was set aside for Azazel, an evil spirit of the wilderness. The high priest transferred the sins of the people onto this goat and sent it away into the desert. (The Book of Answers, by Barbara Berliner)