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The Golden Age of Greece, also referred to as the Classical Period, took place in Greece in the 5th and 4th Centuries BC. This era started when the age of tyranny in Athens finished. Peisistratus, a  known tyrant, died in 528 BC. It took until 510 BC for Greek society to stabilize and begin to flourish once again. This was followed by the rule of Alexander the Great, which was a time of remarkable growth for the Greek people. The end of the Golden Age occurred when Alexander passed away in 323 BC. The Golden Age of Greece was one of the most important times in Greek history. It was a time of remarkable cultural growth, and this is what people most often think of when they picture this time period. Greek theater was invented during this time, and plays written by dramatists such as Aeschylus, Aristophanes, Euripides are still performed today. Other things, such as the Olympic Games were also popular during this time period. This is also when democracy was invented and the Athenian Parthenon was built. This is when the noted philosophers, Socrates and Aristotle, were alive. Socrates' method of questioning is still modeled today in today’s schools and universities. Aristotle was one of Socrates’ students who made important contributions to philosophy and intellectual thought. He was also one of Alexander the Great’s tutors when Alexander was a child.

The Hardy-Weinberg equilibrium is a principle stating that the genetic variation in a population will remain constant from one generation to the next in the absence of disturbing factors. The principle predicts that both genotype and allele frequencies will remain constant. The Hardy-Weinberg principle describes an idealized state of a population. For a population to be in this kind of state, there can’t be any gene mutations, migrations of individuals, genetic drift and natural selection. Also, random mating must occur. When all these conditions are met, it’s said that the population is in equilibrium. But because all of these things commonly occur in nature, the Hardy-Weinberg equilibrium rarely applies in reality. However, The Hardy-Weinberg equations can still be used for any population, even if it is not in equilibrium. There are two equations: 𝑝 + 𝑞 = 1 and 𝑝² + 2𝑝𝑞 + 𝑞² = 1, where 𝑝 is the frequency of the dominant allele, 𝑞 is the frequency of the recessive allele, 𝑝² is the frequency of individuals with the homozygous dominant genotype, 2𝑝𝑞 is the frequency of individuals with the heterozygous genotype and𝑞² is the frequency of individuals with the homozygous recessive genotype. The first equation tells us that the sum of the frequencies of all alleles of one gene locus in one generation is 100%, while the second one tells us that the sum of the frequencies of all genotypes for one gene locus in one population is also100%.

Caleb Bradham, called "Doc" Bradham by friends and acquaintances, was the owner of a pharmacy at the end of the nineteenth century.  In his pharmacy, Doc Bradham had a soda fountain, as was customary in pharmacies of the time.  He took great pleasure in creating new and unusual mixtures of drinks for customers at the fountain.

Like many other entrepreneurs of the era, Doc Bradham wanted to create a cola drink to rival Coca-Cola.  By 1895, Coca-Cola was a commercial success throughout the United States, and numerous innovators were trying to come up with their own products to cash in on the success that Coca-Cola was beginning to experience.  In his pharmacy, Doc Bradham developed his own version of a cola drink, and Doc's drink became quite popular at his soda fountain.  The drink he created was made with a syrup consisting of sugar, essence of vanilla, cola nuts, and other flavorings.  The syrup was mixed at the soda fountain with carbonated water before it was served.

The drink that Doc Bradham created was originally called "Brad's drink" by those in his hometown of New Bern who visited the soda fountain and sampled his product.  Those who tasted the drink claimed not only that it had a refreshing and invigorating quality but also that it had a medicinal value by providing relief from dyspepsia, or upset stomach.  From this reputed ability to relieve dyspepsia, Doc Bradham created the name of Pepsi-Cola for his drink.  Doc Bradham eventually made the decision to mass market his product, and in 1902 he founded the Pepsi-Cola Company.  The advertising for this new product, of course, touted the drink as an "invigorating drink" that "aids digestion."

Susan B. Anthony, teacher by trade and lifelong champion of women's rights, participated throughout her adulthood in the effort to improve the status of women in the United States and to gain rights for them.  She was a stalwart champion of economic independence for women, recognizing the importance of financial independence to the emancipation of women.

She worked tirelessly from 1854 to 1860 in the fight to obtain rights for married women in the state of New York.  She spoke out on the issues, organized volunteers, and circulated petitions asking that married women be granted the rights to own property, to earn wages, to have custody of their children in the event of divorce, and to vote.  In 1860, the landmark Married Women's Property Act, which conferred all of the above rights except the right to vote, was passed in the state of New York.  It became law in large part due to the efforts of Anthony.

In the years following the Civil War, Anthony dedicated her life to obtaining the right to vote for women.  She believed that the right to vote should be a federal right and should not be left up to the discretionary authority of each individual state.  Throughout the rest of her career, she worked on the national level toward the accomplishment of this goal.

Unfortunately, Anthony did not live to see her dream accomplished.  In 1900, at the age of 80, she retired from the presidency of the National American Woman Suffrage Association without having fulfilled her goal of achieving the vote for women but with the undertaking well underway.

When the vote was finally granted to women in the United States in 1920, Anthony was given credit as a primary contributor in the accomplishment of this monumental change in social structure.  In recognition of Anthony's accomplishments, the United States government issued a one-dollar coin in her honor in 1979.  The front side of the coin contained a side view of Anthony's face and was inscribed across the top with the word "liberty."

Eugene O'Neill is regarded as one of the best, if not the best, of America's dramatists.  He was noted and well regarded during his life; however, it was after his demise that his works took their position of preeminence in the theater.|O'Neill experimented with various theatrical techniques before settling on the realistic style for which he received the most recognition.  In his earlier works, he incorporated such devices as transporting Greek myths into modern settings, having characters wear masks to show their feelings and emotions, and allowing the audience to hear characters' inner voices in addition to their actual conversations.|But it is generally for the realistic and often semi-autobiographical plays written later in his life that O'Neill is most renowned. {The Iceman Cometh {depicts the Greenwich Village milieu of friends and acquaintances, with their unrealistic and unrealized aspirations. { A Long Day's Journey into Night{ is a clearly autobiographical depiction of O'Neill's own family life.  {A Moon for the Misbegotten{ presents the final days of O'Neill's alcoholic brother.|Eugene O'Neill did not go unrecognized during his lifetime; the genius of his work was, in fact, well recognized.  In 1936, he was awarded the Nobel Prize for Literature, and over the years he received Pulitzer Prizes for four of his plays.|However, he did die largely forgotten.  Much of his best work, initially not considered commercially viable, achieved considerable prominence after his death.  {The Iceman Cometh,{ which was written in 1939, was revived in 1956, three years after O'Neill's passing.  The unanticipated success of {The Iceman Cometh{ led to the premiere of {A Long Day's Journey into Night.{  Considered by many to be O'Neill's masterpiece, {A Long Day's Journey into Night{ had actually been finished by the playwright in 1941, 12 years before his death, but it never graced the stage during his lifetime.

The question of lunar formation has long puzzled astronomers.  It was once theorized that the moon formed alongside the earth as material in a swirling disk coalesced to form both bodies.  However, if both bodies formed simultaneously out of the same substance, we would expect the mean densities to be more or less identical.  In fact, this is not the case at all.  One of the most curious characteristics of the moon is that it is far less dense than the earth.  Compared to the earth's mean density, which is 5.5 times that of water, the density of the moon is a mere 3.3 times that of water.  Most of the earth's mass is located in its dense iron core, while the mantle and crust are composed primarily of lighter silicates.  The moon, on the other hand, is composed entirely of lighter substances.|An alternate explanation, the "capture theory," suggested that  the moon formed far away and was later captured by the earth.  The moon was once wandering in space, like an asteroid, unattached to a planet.  The rogue satellite veered too close to the earth and has since been tethered by the earth's gravitational field.  However, comparison of lunar and terrestrial isotopes has undermined this theory.  Isotopes are atomic indicators that leave a sort of geological fingerprint.  The isotopes from lunar rock samples indicate that both earth and moon came from the same source.|A more recent theory, the "impact theory" of lunar formation postulates that a large planet-like object, perhaps twice the mass of Mars, struck the earth at a shallow angle.  The object disintegrated a portion of the earth's crust and mantle, sending a cloud of silicate vapor into orbit around the earth.  In time, most of the material fell back to earth, while the rest coalesced into our moon.|Computer simulations (1997) by Robin Canup and Glen Stewart of the University of Colorado and by Shigeru Ida of the Tokyo Institute of Technology demonstrated that such a scenario is at least theoretically possible.  While the impact theory is attractive in that it explains both why the moon is less dense than the earth and how both bodies could have originated from the same source, it is not without problems. Impact from a Mars-sized body would produce an earth-moon system with twice as much angular momentum as that which is actually observed.  Therefore, although we are closer to resolving the question of lunar formation, the origin of the moon is still shrouded in mystery.

A hoax of some note was apparently perpetrated on {Appleton's Cyclopedia of American Biography,{ an important American biographical dictionary that was published in 1889.  This extensive and well-regarded reference was published with a number of biographies of scientists who most likely never existed or who never actually undertook the research cited in the biographical dictionary.|It was not until some 30 years after {Appleton's Cyclopedia{ was first published that word of the fake biographies began cropping up.  It was noted in a 1919 article in the {Journal of the New York Botanical Garden{ that at least 14 of the biographies of botanists were fake.  Then, in 1937, an article in the {American Historical Review { declared that at least 18 more biographies were false.|The source of the false biographies is not known to this day, but a look at a number of steps in the process by which articles were submitted to the biographical encyclopedia sheds some light on how such a hoax could have occurred.  First, contributors were paid by the number and length of articles submitted, and the contributors themselves, as experts in their respective fields, were invited to suggest new names for inclusion.  Then, the false biographies were created in such a way as to make verification of facts by the publisher extremely difficult in an era without the instantaneous communication of today: the false biographies were all about people who supposedly had degrees from foreign institutions and who had published their research findings in non-English language publications outside of the United States. Finally, the reference itself provides a long list of contributors but does not list which articles each of the contributors submitted, and, because the hoax was not discovered until well after the reference was first published, the publishing company no longer had records of who had submitted the false information.|Unfortunately, the false information about historical research did not disappear with the final publication of the book.  Though it is now out of print, many libraries have copies of this comprehensive and, for the most part, highly useful reference.  Even more significant is the fact that a number of false citations from {Appleton's Cyclopedia{ have cropped up in other reference sources and have now become part of the established chronicle of scientific and historical research.

Polymorphs are minerals with a common composition but distinct internal structures.  Polymorphs exist because of the widely varying physical conditions under which minerals are formed.  Minerals can be formed in the fierce heat well below the earth's surface or in cold, damp domains much closer to the surface.  Most of the elements that make up minerals are widely distributed throughout the planet's crust.  Compounds with like chemical compositions can be created in different physical settings, resulting in compounds with two or more strongly differentiated internal structures, each of which is stable in a different physical setting.  These related minerals with unlike crystal structures are known as polymorphs, which means "several forms."|A commonly cited illustration is carbon, which has four known polymorphs.  Two of the polymorphs of carbon, chaoite and lonsdaleite, are quite rare and have only been found in meteorites. The most widespread of carbon's four polymorphs is graphite, which forms loosely bonded crystals at relatively low temperatures and pressures.  Much of the earth's crust is conducive to the formation of graphite, making graphite the most pervasive of carbon's polymorphs.  Diamond is another polymorph of carbon, one that requires the high temperatures and pressures deep within the earth's crust to form.  Diamond forms at depths lower than 150 kilometers below the earth's surface, at temperatures higher than 1,000 degrees centigrade, and at pressures greater than 50,000 times the pressure on the surface of the earth.  Diamond is brought closer to the surface of the earth when gas-rich magmas from deep in the earth's mantle erupt through cracks known as diatremes, or diamond pipes.  Because of its formation so deep in the earth, diamond forms extremely hard crystals and is the most compact and strongly bonded of the four polymorphs of carbon.

The era of modern sports began with the first Olympic games in 1896, and since the dawn of this new era, women have made great strides in the arena of running.  In the early years, female runners faced numerous restrictions in the world of competitive running.  Even though women were banned from competing in the 1896 Olympics, one Greek woman ran unofficially in the men's marathon.  She had to stop outside the Olympic stadium, finishing with a time of 4 hours and 30 minutes.  Four years later, women were still prohibited from Olympic competition because, according to the International Olympic Committee, it was not appropriate for women to compete in any event that caused them to sweat.  In the 1928 Olympics, women were finally granted permission to compete in running events.  However, because some of the participants collapsed at the finish of the 800-meter race, it was decided to limit women runners to races of 200 meters or less in the Olympics four years later.  The women's 800-meter race was not reintroduced to the Olympic games until 1960.  Over a decade later, in 1972, the 1500-meter race was added.  It was not until 1984 that the women's marathon was made an Olympic event.|Before 1984, women had been competing in long-distance races outside of the Olympics.  In 1963, the first official women's marathon mark of 3 hours and 27 minutes was set by Dale Greig.  Times decreased until 1971, when Beth Bonner first broke the three-hour barrier with a time of 2:55. A year later, President Nixon signed the Title IX law, which said that no person could be excluded from participating in sports on the basis of sex.  This was a turning point in women's running and resulted in federal funding for schools that supported women athletes.  In 1978, Greta Waitz set a new world marathon record of 2:32 at the New York City Marathon.  Joan Benoit broke that record by ten minutes in 1983 and went on to win the first-ever women's Olympic marathon in 1984.

Another type of lizard, Jackson's chameleon is a remarkable model of adaptability, one whose ability to adjust to varying environments exceeds that of other members of its species.  True to the reputation of the species, Jackson's chameleon is a master of camouflage.  Special skin cells called chromatophores enable the chameleon to change the pigment in its skin rapidly and escape detection.  While the lizard is stalking its prey, it moves very slowly, in a deliberate rocking gait so as to appear to be a part of a branch moved by a gentle breeze.  Jackson's chameleon also has the ability to change the shape of its body.  By elongating itself, it can look like a twig; by squeezing its sides laterally, it can appear flattened like a leaf.  These camouflaging techniques also help the chameleon to escape detection from predators.|The color change that is characteristic of all chameleons is not solely for the purpose of camouflage.  Jackson's chameleon, like all lizards, is an ectotherm that depends on the sun to maintain its body temperature.  By changing to a darker color in the morning hours, it can absorb more heat.  Once it has reached its optimal body temperature of 77 degrees Fahrenheit (25 degrees Celsius), it changes to a paler hue.  Through color change, the chameleon can also communicate its mood to other members of the species.|Jackson's chameleon has further exemplified its adaptive nature in a way that surpasses other chameleons in its noteworthy migration to a new home: it has become a well-established resident of the Hawaiian Islands even though it is indigenous to the highland rain forests of Kenya and Tanzania. As the story goes, back in 1972 a pet shop owner on the island of Oahu imported several dozen Jackson's chameleons to be sold as pets.  When the shipment arrived, the reptiles were emaciated and dehydrated, so the pet shop owner released the lizards into his lush garden, assuming that he could recapture them after they had revived.  The chameleons escaped and spread throughout the island, where they thrived in the moist, well-planted tropical flora.  Relishing the habitat of secondary growth forest, agricultural areas, and even residential gardens, the chameleon found a ready-made home in its adopted environment.|Jackson's chameleons continued their unsolicited migration to other islands in the chain as the popular lizards were captured by hikers and other visitors to the island, who took them home and released them in their gardens.  This is now a truly ubiquitous lizard; that is, it is now commonplace on all the major Hawaiian Islands.

In young language learners, there is a critical period of time beyond which it becomes increasingly difficult to acquire a language.  Children generally attain proficiency in their first language by the age of five and continue in a state of relative linguistic plasticity until puberty.  Neurolinguistic research has singled out the lateralization of the brain as the reason for this dramatic change from fluidity to rigidity in language function.  Lateralization is the process by which the brain hemispheres become dominant for different tasks.  The right hemisphere of the brain controls emotions and social functions, whereas the left hemisphere regulates the control of analytical functions, intelligence, and logic.  For the majority of adults, language functions are dominant on the left side of the brain.  Numerous studies have demonstrated that it is nearly impossible to attain a nativelike accent in a second language, though some adults have overcome the odds, after lateralization is complete.|Cognitive development also affects language acquisition, but in this case adult learners may have some advantages over child learners.  Small children tend to have a very concrete, here-and-now view of the world around them, but at puberty, about the time that lateralization is complete, people become capable of abstract thinking, which is particularly useful for language learning. Abstract thinking enables learners to use language to talk about language.  Generally speaking, adults can profit from grammatical explanations, whereas children cannot.  This is evidenced by the fact that children are rather unreceptive to correction of grammatical features and instead tend to focus on the meaning of an utterance rather than its form.  However, language learning theory suggests that for both adults and children, optimal language acquisition occurs in a meaning-centered context.  Though children have the edge over adult language learners with respect to attaining a nativelike pronunciation, adults clearly have an intellectual advantage which greatly facilitates language learning.

In 1796, George Washington, the first president of the United States, resigned after completing two four-year terms in office.  He had remained in the service of his country until he was assured that it could continue and succeed without his leadership.  John Adams took over Washington's position as president in a smooth and bloodless change of power that was unusual for its time.|By the end of Washington's presidency, the American government had been established.  The three branches of government had been set up and were in working order.  The debt had been assumed, and funds had been collected;  treaties with major European powers had been signed, and challenges to the new government authorities had been firmly met.  However, when Washington left office, there were still some unresolved problems.  Internationally, France was in turmoil and on the brink of war; domestically, the contest for political control was a major concern.  In addition, there was still some resistance to governmental policies.|It was within this context that Washington made his farewell address to the nation.  In the address published in a Philadelphia newspaper, Washington advised his fellow politicians to base their views and decisions on the bedrock of enduring principles.  He further recommended a firm adherence to the Constitution because he felt that this was necessary for the survival of the young country.  He asked that credit be used sparingly and expressed concerns about the unity, the independence, and the future of the young country.  In regard to relations with foreign powers, he encouraged the country not to be divided by the conflicts in Europe.  Stating that foreign influences were the foe of the republican government, he maintained that relations were to be strictly commercial and not political.  He pleaded with the American public to guard their freedoms jealously.  Finally, he reminded all citizens of the need for religion and morality and stated his belief that one cannot have one without the other.

What yoga does to your body and brain?

Between the 1st and 5th century C.E., hindu sage Patanjali recorded Indian meditative tradition in 196 manuals called the Yoga Sutras. He defined yoga as restraining of mind from focusing on external things in order to achieve full consciousness. According to him, there are 3 core approaches to yoga: Physical posture, Breathing exercise and Spiritual contemplation.
For a long time scientists have been studying the effects of yoga. However, it is hard to make specific claims. Since experiments are performed on small groups of people, results are lacking diversity. Results are, also, subjective due to self reporting. Moreover, because of the unique set of yoga activities, it is hardly possible to determine what activity produces what health benefit.
Nevertheless there are some benefits that have scientific support. Firstly, it is proven that yoga increases strength and flexibility. Stretching, through yoga postures, brings water to muscles. As a result, stem cells, which differentiate in muscle and tissue cells, are produced. Also, yoga has a great therapeutic effect on musculo-skeletal disorders. It reduces pain and improves mobility.
Furthermore, yoga is proven to have benefits on the lung and heart. People with lung disorders such as asthma and bronchitis, have shrunk passageways that carry oxygen and weakened membrane that transfers oxygen into blood. Yoga breathing relaxes lung muscles and thus increases oxygen diffusion. Higher concentration of oxygen in blood benefits the heart, lowering blood pressure and reducing risk of cardiovascular diseases.
Moreover, yoga has remarkable psychological effects. Although the most commended yoga benefit, due to lack of evidence, it is the hardest one to prove. It is strongly believed that yoga helps treat depression and anxiety. But, because of the wide variety of diagnosis, origines and severity of those diseases it is hard to determine yoga’s exact impact.

The benefits of a good night sleep
Although sleep occupies nearly ⅓ of our lives, we pay little attention to it. The reason for this neglect is probably a common misconception that sleep lost is time. In fact, during sleep our vital systems are regulated and balanced. Furthermore, sleep restructures our brain, thus positively affecting our memory.
It was scientifically proven a long time ago that we forget 40% of information during the first 20 minutes. This process can be inhibited through memory consolidation. During the consolidation,with the help from the hippocampus, information is transferred from short term to long term memory.
The importance of hippocampus in the memory processes was first proved by scientist Brenda Milner. She discovered that after having his hippocampus removed, the patient's ability to store both short and long term memory significantly decreased. However, he was able to learn physical tasks after repetition. This revealed that the hippocampus was involved in the consolidation of long term declarative memory(facts), but not in the consolidation of procedural memory.
As the technology developed, our understanding of the consolidation process improved. First, data is captured in neurons. Then, neurons travel to the hippocampus where, during neuroplasticity, synaptic buds are formed, strengthening the neural network where the information will be returned as long-term memory.
In some situations in life memory consolidation is better than in others. For example, we better remember information received during stress or some other high emotional state. This can be explained with the link hippocampus has with emotion. But one of the major factors contributing to memory consolidation is sleep.
Sleep is divided in 4 stages, deepest of whom are Slow Wave Sleep and Rapid Eye Movement (REM). EEG machines monitoring stages of sleep discovered impulses traveling between the brainstem, hippocampus, thalamus and cortex. Thus, scientists discovered what type of memory is consolidated by every stage.
During Slow Wave Sleep stage declarative memory is encoded in temporary storage in the interior part of the hippocampus. There, through the continuous dialog of the hippocampus and cortex, it is reactivated and as a result stored in long term storage. In the REM phase, procedural memory is consolidated.

Today’s shopping mall has as its antecedents historical marketplaces,such as Greek agoras, European piazzas, and Asian bazaars. The purposeof these sites, as with the shopping mall, is both economic andsocial. People go not only to buy and sell wares, but also to be seen,catch up on news, and be part of the human drama. Both the marketplaceand its descendant the mall might also contain restaurants,banks, theaters, and professional offices.The mall is also the product of the creation of suburbs. Althoughvillages outside of cities have existed since antiquity, it was the technologicaland transportation advances of the 19th century that gaverise to a conscious exodus of the population away from crowded,industrialized cities toward quieter, more rural towns. Since the suburbstypically have no centralized marketplace, shopping centers ormalls were designed to fill the needs of the changing community, providingretail stores and services to an increasing suburban population.The shopping mall differs from its ancient counterparts in a numberof important ways. While piazzas and bazaars were open-air venues,the modern mall is usually enclosed. Since the suburbs are spreadout geographically, shoppers drive to the mall, which means that parkingareas must be an integral part of a mall’s design. Ancient marketplaceswere often set up in public spaces, but shopping malls aredesigned, built, and maintained by a separate management firm as aunit. The first shopping mall was built by J. C. Nichols in 1922 nearKansas City, Missouri. The Country Club Plaza was designed to be anautomobile-centered plaza, as its patrons drove their own cars to it, rather than take mass transportation as was often the case for city shoppers. It was constructed according to a unified plan, rather thanas a random group of stores. Nichols’ company owned and operated the mall, leasing space to a variety of tenants.The first enclosed mall was the Galleria Vittoria Emanuele in Milan, Italy in 1865–77. Inspired by its design, Victor Gruen took the shopping and dining experience of the Galleria to a new level when he created the Southdale Center Mall in 1956. Located in a suburb of Minneapolis, it was intended to be a substitute for the traditional city center. The 95-acre, two-level structure had a constant climate-controlled temperature of 72 degrees, and included shops, restaurants, a school, a post office, and a skating rink. Works of art, decorative lighting, fountains, tropical plants, and flowers were placed throughout the mall. Southdale afforded people the opportunity to experience the pleasures of urban life while protected from the harsh Minnesota weather. In the 1980s, giant megamalls were developed. While Canada has had the distinction of being home to the largest of the megamalls for over twenty years, that honor will soon go to Dubai, where the Mall of Arabia is being completed at a cost of over five billion U.S. dollars. The 5.3 million square foot West Edmonton Mall in Alberta, Canada, opened in 1981, with over 800 stores, 110 eating establishments, a hotel, an amusement park, a miniature-golf course, a church, a zoo, and a 438-foot-long lake. Often referred to as the “eighth wonder of the world,” the West Edmonton Mall is the number-one tourist attraction in the area, and will soon be expanded to include more retail space, including a facility for sports, trade shows, and conventions. The largest enclosed megamall in the United States is Bloomington, Minneapolis’s Mall of America, which employs over 12,000 people. It has over five hundred retail stores, an amusement park which includes an indoor roller coaster, a walk-through aquarium, a college, and a wedding chapel. The mall contributes over one billion dollarseach year to the economy of the state of Minnesota. Its owners haveproposed numerous expansion projects, but have been hampered by safety concerns due to the mall’s proximity to an airport.