"...look into all things with a searching eye” - Baha'u'llah (Prophet Founder of the Baha'i Faith)

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Apr 11, 2015

Global Undernourishment

Global undernourishment shouldn't exist. Each day the world's farmers produce the equivalent of 2,868 calories per person on the planet -- enough to surpass the World Food Programme's recommended intake of 2,100 daily calories and enough to support a population inching toward nine billion. The world as a whole does not have a food deficit, but individual countries do.

Why do 805 million people still have too little to eat? Access is the main problem. Incomes and commodity prices establish where food goes. The quality of roads and airports determines how easily it gets there. Even measuring undernourishment is a challenge. In countries with the highest historical proportions of undernourishment, it can be hard to get food in and data out.

Things are slowly getting better. Since the early 1990s world hunger has dropped by 40 percent -- that means 209 million fewer undernourished people, according to the Food and Agriculture Organization of the United Nations. Future progress may prove difficult. "It is critical to first improve overall food production and availability in places like sub-Saharan Africa," says FAO economist Josef Schmidhuber. "Then one can focus on access." 
(Daniel Stone, National Geographic Magazine, December 2014)

Apr 3, 2015

Sources of Calcium in our diet...

Calcium in 100 calories of:
                                              mg
  • bok choy                         775
  • turnip greens                   685
  • collard greens                  539
  • tofu                                 287
  • kale                                 257
  • romaine lettuce               194
  • milk                                189
  • sesame seeds, unhulled   170
  • broccoli                           114
  • cucumber                        107
  • carrots                             81
  • cauliflower                       70
  • soybeans                         59
  • flaxseeds                         48
  • fish                                  33
  • eggs                                32
  • pork chop                         4
  • T-bone steak                    3
(‘Eat to Live’, by Dr. Joel Fuhrman, M.D.)

Apr 2, 2015

1920s & 1930s: New Guinea Highlanders meet Europeans for the first time


The Europeans began expanding over the globe from AD 1492 onwards and "discovered people long before there were any airplane overflights to alert them to an outside world. The last large-scale first contacts in world history will prove to be those that took place in the New Guinea Highlands, where from the 1930s to the 1950s patrols by Australian and Dutch government and army reconnaissance expeditions, miners on prospecting trips, and biological expeditions “discovered" a million Highlanders of whose existence the outside world hadn't known and vice versa - even though Europeans had by then been visiting and settling the coasts of New Guinea for 400 years. 

Mar 28, 2015

The Gravitational Radius, also known as Schwarzschild Radius

Defined by German astronomer, Karl Schwarzschild the gravitational radius is the distance that defines the size at which a spherical astronomical object such as a star becomes a black hole. A black hole is an object so dense that not even light can escape the pull of its gravitational force. If an object collapses to within its Schwarzschild radius, it becomes a black hole. Karl Schwarzschild derived the first model of a black hole in 1916.

Nothing, not even a particle moving at the speed of light, can escape the gravitational pull of a black hole. Therefore, the Schwarzschild radius is the largest radius that a body with a specific mass can have and still keep light from escaping. The formula for the Schwarzschild radius of a body is Rs = GM/c2, where Rs is the Schwarzschild radius of the body, G is a constant known as the universal constant of gravitation, M is the mass of the object, and c is the speed of light.

Mar 20, 2015

Paper – its historical development

Paper has been traced to China in about AD 105. It reached Central Asia by 751 and Baghdad by 793, and by the 14th century there were paper mills in several parts of Europe. The invention of the printing press in about 1450 greatly increased the demand for paper, and at the beginning of the 19th century wood and other vegetable pulps began to replace rags as the principal source of fiber for papermaking.

The word paper is derived from the name of the reedy plant papyrus, which grows abundantly along the Nile River in Egypt. In ancient times, the fibrous layers within the stem of this plant were removed, placed side by side, and crossed at right angles with another set of layers similarly arranged. The sheet so formed was dampened and pressed. Upon drying, the gluelike sap of the plant, acting as an adhesive, cemented the layers together. Complete defibring, an indispensable element in modern papermaking, did not occur in the preparation of papyrus sheets. Papyrus was the most widely used writing material in ancient times, and many papyrus records still survive.

Mar 15, 2015

Bruno Giardano (1548-1600) – proposed an infinite universe

Italian philosopher, astronomer, mathematician, and occultist whose theories anticipated modern science. The most notable of these were his theories of the infinite universe and the multiplicity of worlds, in which he rejected the traditional geocentric (or Earth-centred) astronomy and intuitively went beyond the Copernican heliocentric (Sun-centred) theory, which still maintained a finite universe with a sphere of fixed stars. Bruno is, perhaps, chiefly remembered for the tragic death [his tongue in a gag, and burned alive] he suffered at the stake because of the tenacity with which he maintained his unorthodox ideas at a time when both the Roman Catholic and the Reformed churches were reaffirming rigid Aristotelian and Scholastic principles in their struggle for the evangelization of Europe….

Bruno's theories influenced 17th-century scientific and philosophical thought and, since the 18th century, have been absorbed by many modern philosophers. As a symbol of the freedom of thought, Bruno inspired the European liberal movements of the 19th century, particularly the Italian Risorgimento (the movement for national political unity). Because of the variety of his interests, modern scholars are divided as to the chief significance of his work. Bruno's cosmological vision certainly anticipates some fundamental aspects of the modern conception of the universe; his ethical ideas, in contrast with religious ascetical ethics, appeal to modern humanistic activism; and his ideal of religious and philosophical tolerance has influenced liberal thinkers. On the other hand, his emphasis on the magical and the occult has been the source of criticism as has his impetuous personality. Bruno stands, however, as one of the important figures in the history of Western thought, a precursor of modern civilization. 
(Britannica Encyclopedia)

Mar 10, 2015

Salt and blood pressure

Let's now pause for a quick crash course on blood pressure and hypertension, to help you understand what those numbers mean when your doctor inflates a rubber cuff about your arm, listens, deflates the cuff, and finally pronounces, "Your blood pressure is 120 over 80." Blood pressure is expressed in units of millimeters of mercury: the height to which your blood pressure would force up a column of mercury in case, God forbid, your artery were suddenly connected to a vertical mercury column.

Naturally, your blood pressure changes throughout each heart stroke cycle: it rises as the heart squeezes, and it falls as the heart relaxes. Hence your physician measures a first number and then a second number (e.g., 120 and 80 millimeters of mercury), referring respectively to the peak pressure at each heartbeat (called systolic pressure) and to the minimum pressure between beats (termed diastolic pressure). Blood pressure varies somewhat with your position, activity, and anxiety level, so the measurement is usually made while you are resting flat on your back and supposedly calm. Under those conditions, 120 over 80 is an average reading for Americans. There is no magic cut-off between normal blood pressure and high blood pressure. Instead, the higher your blood pressure, the more likely you are to die of a heart attack, a stroke, kidney failure, or a ruptured aorta. Usually, a pressure reading higher than 140 over 90 is arbitrarily defined as constituting hypertension, but some people with lower readings will die of a stroke at age 50, while others with higher readings will die of a car accident in otherwise good health at age 90.

Mar 6, 2015

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 "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.

Feb 22, 2015

Is it dangerous to eat more fruits and vegetables because of the increased consumption of pesticides? Do I have to buy organic?

The effects of ingesting pesticides in the very small amounts present in vegetation are unknown. Bruce Ames, Ph.D., director of the National Institute of Environmental Health Sciences Center at the University of California at Berkeley, who has devoted his career to examining this question, believes these minute amounts pose no risk at all. 

He and other scientists support this view because humans and other animals are exposed to, small amounts of naturally occurring toxins with every mouthful of organically grown, natural food. The body normally breaks down self-produced metabolic wastes and naturally occurring carcinogens in foods, as well as pesticides, and excretes these harmful substances every minute. Since 99.99 percent of the potential carcinogenic chemicals consumed are naturally present in all food, reducing our exposure to the 0.01 percent that are synthetic will not reduce cancer rates.

These scientists argue that humans ingest thousands of natural chemicals that typically have a greater toxicity and are present at higher doses than the very minute amount of pesticide-residues that remain on food. Furthermore, animal studies on the carcinogenic potential of synthetic chemicals are done at doses a thousand fold higher than what is ingested in food. Ames argues that a high percentage of all chemicals, natural or not, are potentially toxic in high doses - "the dose makes the poison” - and that there is no evidence of possible cancer hazards from the tiny chemical residue remaining on produce.

Feb 15, 2015

Omar Khayyam (1048-1131)

Omar Khayyam was a Persian mathematician, astronomer, and poet, renowned in his own country and time for his scientific achievements but chiefly known to English-speaking readers through the translation of a collection of his poems known as Robáiyyát (“quatrains”) in ‘The Rubáiyát of Omar Khayyám’ (1859), by the English writer Edward FitzGerald.

He was born in Neyshábúr [also spelled Nīshápúr], which is now located in Iranian province of Khorásán. His name Khayyam (“Tent-maker”) may have been derived from his father's trade. He received a good education in the sciences and philosophy in his native Neyshábúr before traveling to Samarkand (now in Uzbekistan), where he completed his algebra treatise: “Treatise on Demonstration of Problems of Algebra”. This mathematical treatise enhanced his reputation significantly. In this treatise he gave a systematic discussion of the solution of cubic equations by means of intersecting conic sections.

He made such a name for himself that the Persian King Malik-Sháh invited him to Esfahán to undertake the astronomical observations necessary for the reform of the calendar. To accomplish this an observatory was built there, and a new calendar was produced, known as the Jalálí calendar. Based on making 8 of every 33 years leap years, it was more accurate than the present Gregorian calendar, and it was adopted in 1075 by Malik-Sháh. In Esfahán he also produced fundamental critiques of Euclid's theory of parallels as well as his theory of proportion. In connection with the former his ideas eventually made their way to Europe, where they influenced the English mathematician John Wallis (1616–1703); in connection with the latter he argued for the important idea of enlarging the notion of number to include ratios of magnitudes.

Feb 8, 2015

Our salt intake

While there are many different chemicals falling into the category termed "salts" by chemists, to laypeople "salt" means sodium chloride. That's the salt that we crave, season our food with, consume too much of, and get sick from. Today, salt comes from a salt-shaker on every dining table and ultimately from a supermarket, is cheap, and is available in essentially unlimited quantities. Our bodies' main problem with salt is to get rid of it, which we do copiously in our urine and in our sweat. The average daily salt consumption around the world is about 9 to 12 grams, with a range mostly between 6 and 20 grams (higher in Asia than elsewhere).

Traditionally, though, salt didn't come from salt-shakers but had somehow to be extracted from the environment. Imagine what the world used to be like before salt-shakers became ubiquitous. Our main problem with salt then was to acquire it rather than to get rid of it. That's because most plants contain very little sodium, yet animals require sodium at high concentrations in all their extracellular fluids. As a result, while carnivores readily obtain their needed sodium by eating herbivores full of extracellular sodium, herbivores themselves face problems in obtaining that sodium. That's why the animals that you see coming to salt licks are deer and antelope, not lions and tigers. Human hunter-gatherers who consumed much meat, such as the Inuit and San, thus met their salt requirement readily, though even their total salt intake was only 1 or 2 grams per day because much of their prey's sodium-rich blood and other extracellular fluids became lost in the course of butchering and and cooking. Among traditional hunter-gatherers and farmers consuming a diet high in plant food and with limited meat, those living on the seacoast or near inland salt deposits also have easy access to salt. For instance, average daily salt consumption is around 10 grams among the Lau people of the Solomon Islands, who live on the coast and use salt water for cooking, and also among Iran's Qashqa'i nomadic herders, whose homeland has natural salt deposits on the surface.

Feb 1, 2015

A Map of People Not of Land Mass

This map shows what the world would look like if a country's size were proportional to its population. It radically rearranges our sense of geographic space. Vast countries such as Russia, Canada and Australia turn into slivers of territory. Europe, and not South Asia, appears to be the red Asian subcontinent. 

Compiled by Reddit user TeaDranks, the map is an adapted version of a Population Map made in 2005 by cartographer Paul Breding and published by ODTmaps.com. TeaDranks updated its numbers. What the map emphasizes is the primacy of Asia. The continent's immensity is understood in the West but not truly appreciated. That, of course, is echoed in the Western media, where crises in Europe and conflicts in the Middle East still hold far more attention.

The lack of coverage of India's elections last year - the world's greatest exercise in democracy - was lampooned by comedians. And many Americans probably weren't even aware of a similar landmark vote in Indonesia, home to the world's largest population of Muslims, or of Saturday's upcoming presidential vote in Nigeria, which will continue its longest stretch of democracy.

Some Asian cities, as delineated on the map, are larger than most European countries. As the continent boasts some of the world's most dynamic developing economies, this map is a useful illustration for why some believe the 21st century will be the Asian Century.

Jan 25, 2015

The world's language total -- 7,000, nine giants: Mandarin, Spanish, English, Arabic, Hindi, Bengali, Portuguese, Russian, and Japanese

The known number of distinct languages still spoken or recently spoken in the modern world is around 7,000. That huge total may astonish many readers, because most of us could name only a few dozen languages, and the vast majority of languages are unfamiliar to us. Most languages are unwritten, spoken by few people, and spoken far from the industrial world. For example, all of Europe west of Russia has fewer than 100 native languages, but the African continent and the Indian subcontinent have over 1,000 native languages each, the African countries of Nigeria and Cameroon 527 and 286 languages respectively, and the small Pacific island nation of Vanuatu (area less than 5,000 square miles) 110 languages. The world's highest language diversity is on the island of New Guinea, with about 1,000 languages and an unknown but apparently large number of distinct language families crammed into an area only slightly larger than Texas.

Jan 18, 2015

Marco Polo (1254-1324)

A Venetian traveler and author, whose account of his travels and experiences in China offered Europeans a firsthand view of Asian lands and stimulated interest in Asian trade.

Marco Polo was born in Venice, one of the most prominent centers of trade in medieval Europe, into a merchant family. Venetian merchants of the day traded regularly throughout the Mediterranean region. They also maintained trading posts in port cities on the Black Sea, where they obtained silk, porcelain, and other goods that came from China over the Silk Road, an ancient trade route linking China with Rome. Little is known about Marco Polo’s early life, because his own account of his travels, published later in his life, is the primary source of biographical material about him. Polo probably received a fairly typical education for children of merchants at that time, learning how to read, write, and calculate.

Marco Polo’s account is also the primary source of information about the travels of his father and uncle, Niccolò and Maffeo Polo, who were jewel merchants. They left Venice in 1260 on a commercial venture to the Black Sea ports of Constantinople (now İstanbul, Turkey) and Soldaia (now Sudak, Ukraine). From Soldaia they continued farther east to trading cities on the Volga River in present-day Russia. In 1262 a war broke out behind them and prevented them from returning home, so they proceeded farther east to the great Central Asian trading city of Bukhara (in present-day Uzbekistan). After three years there they joined a diplomatic mission going to the court of Kublai Khan, the Mongol ruler of China. The khan received them warmly and expressed a desire to learn more about Christianity. He asked the Polo brothers to return to Europe and persuade the pope to send Christian scholars who could explain the religion to him. Niccolò and Maffeo journeyed back to Europe in 1269 to satisfy the khan’s request.

Jan 11, 2015

Sultan ‘Abdu’l-Aziz

He was the 32nd Sultan of the Ottoman Empire and the 111 Caliph of the Muslim community.  He reigned between 1861 and 1876. He was the son of Sultan Mahmud II and succeeded his brother ‘Abdu’l-Majid I. He continued the westernizing reforms that had been initiated by his predecessors until 1871, after which his reign took an absolutist turn.

Like his brother ‘Abdu’l-Majid I, ‘Abdu’l-Aziz, was an ardent admirer of the material progress in western Europe. Educated in the Ottoman tradition, however, he could not always accept the adoption of Western institutions and customs. ‘Abdu’l-Aziz was a member of the Mawlawiyah (Mevlevi) order of dervishes (Muslim mystics).

Between 1861 and 1871, reforms were continued under the leadership of Abdu’l-Aziz's able chief ministers, Fuad Pasha and ‘Ali Pasha. New administrative districts (vilayets) were set up in 1864; on French advice a council of state was established in 1868; public education was organized on the French model and a new university founded; and the first Ottoman civil code was promulgated. ‘Abdu’l-Aziz cultivated good relations with France and Great Britain and was the first Ottoman sultan to visit western Europe.

Jan 4, 2015

Dogs – first animal to be domesticated by humans

The dog is one of the two most ubiquitous and popular domestic animals in the world (the cat is the other). For more than 12,000 years it has lived with humans as a hunting companion, protector, object of scorn or adoration, and friend. The dog has evolved from similar (that is, undifferentiated) fur-bearing animals into more than 400 distinct breeds. Human beings have played a major role in creating dogs that fulfill distinct societal needs. Through the most rudimentary form of genetic engineering, dogs were bred to accentuate instincts that were evident from their earliest encounters with humans. Although details about the evolution of dogs are uncertain, the first dogs were hunters with keen senses of sight and smell. Humans developed these instincts and created new breeds as need or desire arose.

Dogs are regarded differently in different parts of the world. Western civilization has given the relationship between human and dog great importance, but, in some of the developing nations and in many areas of Asia, dogs are not held in the same esteem. In some areas of the world, dogs are used as guards or beasts of burden or even for food, whereas, in the United States and Europe, dogs are protected and admired. In ancient Egypt during the days of the pharoahs, dogs were considered to be sacred.

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 20, 2014

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.