Monday, April 6, 2009

NIAGRA FALLS FORMATION






























The first humans arrived in Niagara Region almost 12,000 years ago, just in time to witness the birth of the Falls. The land was different then, consisting of tundra and spruce forest. During this time (the Palaeo-Indian Period, which lasted until 9,000 years ago), Niagara was inhabited by the Clovis people. These nomadic hunters likely camped along the old Lake Erie shoreline, living in simple, tiny dwellings. They left little to mark their tenure except chipped stones. These large, fluted projectile points were likely to fell the caribou, mastodons, moose and elk that roamed the land.
By 9,500 years ago a deciduous forest apparently covered southernmost Ontario. This forest supported the hunter-gatherers of the Archaic Period (9,000 to 3,000 years ago) with a diet of deer, moose, fish and plants. Small groups hunted in the winter, feeding on nuts and animals attracted to the forest. Larger groups came together during the summer, setting up fishing camps at the mouths of rivers and along lakeshores.
The Woodland Period lasted from 3,000 to 300 years ago, culminating in the peak of Iroquois culture in southern Ontario. Corn, bean and squash agriculture provided the main sources of food. With their bellies full, the Iroquois had time for other pursuits and the population boomed. Small palisaded villages were built, with nuclear or extended families occupying individual longhouses. During this period, burial rituals and ceramics were introduced to Ontario. Society became more complex with a political system based on extended kinship and inter-village alliances.
When the European explorers and missionaries arrived at the beginning of the 17 th Century, the Iroquoian villages were under the direction of various chiefs elected from the major clans. In turn, these villages were allied within powerful tribal confederacies.
Unfortunately, inter-tribal warfare with the Five Nations Iroquois of New York State, made worse by the intrusion of the Europeans, dispersed the three Ontario confederacies, the Huron, the Petun and the Neutral. Niagara ceased to be the territory of those who lived in harmony with nature. Still, this fascinating period of native occupation cries out for interpretation and study. Since human settlement requires drinking water, sites within 150 metres of rivers and lakeshores have the greatest archaeological potential. Palaeo-Indian sites in Niagara would most likely be associated with the series of relic beach ridges that once formed the shore of early Lake Erie.
In May 1535, Jacques Cartier left France to explore the New World. Although he never saw Niagara Falls, the Indians he met along the St.Lawrence River told him about it. Samuel de Champlain visited Canada in 1608. He, too, heard stories of the mighty cataract, but never visited it. Etienne Brule, the first European to see Lakes Ontario, Erie Huron and Superior, may also have been the first to behold the Falls, in 1615.
That same year, the Recollet missionary explorers arrived in Ontario. They were followed a decade later by the Jesuits. It was a Jesuit father, Gabriel Lalemant, who first recorded the Iroquios name for the river- Onguiaahra, meaning "the Strait". "Niagara" is a simplification of the original.
In 1651, during the fur- trade rivalry between the Huron and Iroquois that was first precipitated by the French, the Iroquois wiped out the Neutrals. Until the American Revolution, they managed to keep white settlers out of Niagara almost completely.
In December 1678, Recollet priest Louis Hennepin visited Niagara Falls. Nineteen years later, he published the first engraving of the Falls in his book Nouvelle Decouverte. The Falls obviously made a great impression of Hennepin, for he estimated their height to be 183 metres, more than three times what it really is.
In 1812, by request of President James Madison, the United States congress declared war on Canada. Artifacts from that war dot the riverside, as do monuments erected later, such as the one to Sir Isaac Brock. Recently, the skeletons of members of the U.S. Army were found near Old Fort Erie.





Following the War of 1812, the region began the slow process of rebuilding itself. Queenston became a bustling community, but Chippawa was the big centre, with distilleries and factories.
In the 1820's, a stairway was built down the bank at Table Rock and the first ferry service across the lower River began. By 1827, a paved road had been built up from the ferry landing to the top of the bank on the Canadian side. This site became the prime location for hotel development and the Clifton was built there, after which the Clifton Hill is named.
Niagara has perhaps the most complex transportation history of any area in North America. The first Welland Canal was completed in 1829. Between 1849 and 1962, thirteen bridges were constructed across the Niagara River Gorge. Four of them remain.
The roadway between Niagara-on-the-Lake and Chippawa was the first designated King's Highway. The first stage coach in Upper Canada operated on this roadway between the late 1700s and 1896. The first railroad in Upper Canada opened in 1841 with horse-drawn carriages running between Chippawa and Queenston. In 1854 it was converted to steam and relocated to serve what was to become the Town of Niagara Falls.





In 1855, John August Roebling, the designer of the Brooklyn Bridge, built the Niagara Railway Suspension Bridge, the first bridge of its type in the world. Between the late 1700s and the middle 1800s, boats were the main way to get to Niagara Falls. By 1896, three boats plied the route between Toronto and Queenston.
One of the first electrified street car services was provided in Niagara, and in 1893 the Queenston/Chippawa Railway carried boat passengers from Queenston to Table Rock and beyond. In 1902, a railway was constructed across the Queenston Suspension Bridge. Later it was extended along the lower Gorge on the American side of the River, connecting back into Canada at the Upper Arch Bridge. This transit line, the Great Gorge Route, continued in service until the Depression. The use of boats declined as tourists increasingly chose to visit Niagara by automobile, bus or train.
Tourism travel to the Falls began in the 1820s and within 50 years it had increased ten-fold to become the area's dominant industry.
After World War 1, automobile touring became popular. As a response, attractions and accommodations sprang up in strip developments, much of which still survives.


































































BRAIN SECRET


The Location of Memory
In the past, it was thought that all memory was in the brain. However, Gazzaniga (1988) reports that memory occurs throughout the nervous system. So every thought you have is “felt” throughout your entire body because the receptors for the chemicals in your brain are found on the surfaces of cells throughout your body. Thus when the chemicals are activated across synapses in the brain, the message is communicated to every part of your body by chemotaxis, a process that allows cells to communicate by “radar” or remote travel using blood and cerebrospinal fluid. In more extreme cases, the body sometimes buries intensely painful memories in muscle tissue so that the conscious mind is spared the depth of trauma. Then when that person receives deep tissue massage or bodywork such as Rolfing, and the muscles are stimulated, the memories can be reactivated, causing the person to experience the repressed emotions. Another example of muscle memory is evident with organ transplants. People who have received donor organs have reported experiencing cravings or emotional reactions to certain incidents that they never had before.
The Biology of Memory
What it comes down to is brain cells, or neurons, communicating with each other through electo-chemical pathways. An electrical impulse travels down the axon or “outgoing branch”. Then the “fingers” at the end are stimulated to release chemicals called neurotransmitters (tiny molecules that send specific messages). The dendrites or “incoming branches” of other neurons pick these up. The space between the axon and dendrites is called a synapse.
Solidifying the Synapse
For learning to “stick”, the synapses need time to “gel”. If the synapse doesn’t “gel” then recreating the event, i.e. recalling the memory is difficult, if not impossible. A research team comprised of scientists from the University of Texas Medical School at Houston and the University of Houston reported the discovery of a new protein – transforming growth factor-B (TGF-B) that acts to solidify the new synapses (Science, March 1997). However, if there is too much protein it can build up and “clog” the synapse, thus reducing memory recall. Usually the neurotransmitter calpain, found in calcium, keeps the buildup of protein down. So, inadequate dietary calcium means that too much protein can build up because there is not enough calpain to keep the synapses clean. Unfortunately, an excess of calcium in the diet also creates a problem because the calpain starts to interfere with proper neural transmissions. A drastic way to remove excess protein from the synapse is by electric shock. Acetylcholine, one type of neurotransmitter, is important for three reasons: it is necessary for activating REM (rapid eye movement) sleep, it keeps neural membranes in tact so that they don’t become brittle and fall away, and it breaks down the excess build up of amyloid protein at the synapses found in Alzheimer’s patients (Robert Wurtham, director of the Clinical Research Center at Massachusetts Institute of Technology).
Stress Erodes Memory
Excessive stress and obesity produce an over-production of a complex set of stress hormones called glucocorticoids (cortisol being one example). Over exposure to glucocorticoids damages and destroys neurons in the brain’s hippocampus – a region critical to learning and memory. One really good way to burn off excess cortisol is through exercise. So for those experiencing particularly high stress levels exercise is not only beneficial, it is necessary.
What are the Characteristics of Memory?
Sensory – we remember things that involve our five senses. So, the more senses that get activate, the easier it will be to recall.
Intensity – when something is more intensely funny, sexual, absurd, etc. it tends to stand out in our memories.
Outstanding – things that are dull and unoriginal are more difficult to remember because there is nothing to distinguish them from all the other memories.
Emotional – the amygdala – a round, pea-sized part in the middle of the brain - acts as a gate keeper, so when something happens that has high emotional content – positive or negative – the amygdale says, “This is important!” and we tend to remember it more easily.
Survival – the brain is wired for survival. This means that anything we perceive as important to survival we will remember more easily. It’s not just physical survival. Survival can include, emotional survival, psychological survival and financial survival.
Personal importance – we naturally remember things that interest us and that have some personal importance.
Repetition – the more often we recall information, the better we get at recalling on demand.
First and last – the brain most easily recalls things from the beginning and the ending of any session or lecture.
What are the Keys to Memory?
Pay attention – often times the biggest problem is that people’s minds are not focused in the moment. Instead, they are thinking about something in the past of future.
Visualization – create a visual in your mind because the brain thinks in pictures and concepts, not paragraphs.
Association – find something to connect the information to…similar to word association. Ask, “What does this remind me of?”
Imagination – get creative when visualizing or making associations.
Why do we forget?
It could be that we never stored the information properly in the first place. It could be because there was not enough emotion or personal importance connected to the information to make it stick. It could be that it was so emotionally traumatic that the mind suppressed it in order to maintain normalcy.
Why do we remember negative events?
Whenever emotions are activated, especially strong emotions, the information or experience is entrenched into memory. Often times we tend to dwell on it, thereby rehearsing it and entrenching it even further. It is also easier to recall negative memories when we are in a bad mood. Why? Because we remember things in the state that we learned them so whenever you are feeling angry you will more easily recall other situations in which you were angry.
The subconscious remembers everything
If we were to compare the conscious mind with the subconscious, the conscious would measure about one foot long and the subconscious would be the length of a football field. The potential is enormous. So everything we experience can be stored. However, the conscious mind would get overloaded trying to process all the incoming bits of data on a daily basis. Instead, all the information goes into the subconscious for storage and we may never deal with it, except if the mind chooses to process it at night through dreams. Or, if we go for clinical hypnosis, through which a therapist assists in accessing information or memories the conscious mind has “forgotten” or repressed.

GLOBAL WARMING....












Scientists predict that if global warming continues, the world's major ice shelves will melt by 2100, causing oceans to rise by 7m to 14m, devastating coastal areas worldwide.
1. Science Predictions about Global Warming
Most scientists today agree that the Earth is heating up, due primarily to an atmospheric increase in carbon dioxide caused mainly by the burning of fossil fuels such as coal and petroleum. 2005 was the hottest year on Earth since the late 19th century, when scientists began collecting temperature data. The past decade featured five of the warmest years ever recorded, with the second hottest year being 1998.
Global mean surface temperatures 1850 to 2006Source: Wikipedia
The image above shows the instrumental record of global average temperatures as compiled by the Climatic Research Unit of the University of East Anglia and the Hadley Centre of the UK Meteorological Office.
Mean surface temperature anomalies during the period 1995 to 2004 with respect to the average temperatures from 1940 to 1980Source: The geographic distribution of surface warming during the 21st century calculated by the HadCM3 climate model if a business as usual scenario is assumed for economic growth and greenhouse gas emissions.In this figure, the globally averaged warming corresponds to 3.0 °C (5.4 °F) Source:
Arctic Meltdown
Global sea levels could rise by more than 20 feet (6 meters) with the loss of shelf ice in Greenland and Antarctica, devastating coastal areas worldwide.
There is little doubt that sea levels would rise by that much if Greenland melted. But scientists disagree on when it could happen.
A recent Nature study suggested that Greenland's ice sheet will begin to melt if the temperature there rises by 3ºC (5.4ºF) within the next hundred years, which is quite possible, according to leading temperature-change estimates.
Many experts agree that even a partial melting would cause a one-meter (three-foot) rise in sea levels, which would entirely submerge low-lying island countries, such as the Indian Ocean's Maldives.
The Arctic Ocean could be ice-free in summer by 2050.
Some climate models are more conservative, suggesting that there will be no summer ice in the Arctic by the year 2100. But new research shows it could take as little as 20 years for the sea ice to disappear.
"Since the advent of remote satellite imaging, we've lost about 20 percent of sea-ice cover. We think of the Arctic as the heat sink to the climate system. We're fundamentally changing this heat sink, and we don't know how the rest of the climate system is going to respond." -- Mark Serreze, a research scientist at the National Snow and Ice Data Center in Boulder, Colorado.
Sources:

Arctic meltdown just decades away, scientists warn
By David Adam in London September 30, 2005
Global warming in the Arctic might be accelerating out of control, scientists have warned, as new data revealed the floating cap of sea ice has shrunk to probably its smallest in at least a century.
This satellite im shows the Arctic sea ice spread on September 21, 2005, when it dropped tothe lowest extent yet recorded. The yellow outline indicates where the concentration of ice was as of September 21, 1979. Photo: AFP
Experts at the US National Snow and Ice Data Centre in Colorado fear the region is locked into a destructive cycle, with warmer air melting more ice, which in turn warms the air further. Satellite pictures show that the extent of Arctic sea ice this month dipped 20 per cent below the long-term average for September - melting an extra 1.3 million square kilometres - an area about the size of the Northern Territory. If current trends continue, the summertime Arctic Ocean will be ice-free well before the end of this century.
The head scientist at the Colorado centre, Ted Scambos, said melting sea ice accelerates warming because dark-coloured water absorbs heat from the sun that was previously reflected back into space by white ice.
"Feedbacks in the system are starting to take hold. We could see changes in Arctic ice happening much sooner than we thought and that is important because without the ice cover over the Arctic Ocean we have to expect big changes in Earth's weather," Dr Scambos said.
The findings are consistent with recent computer simulations showing that a build-up of greenhouse gases could lead to a profoundly transformed Arctic later this century. The North Pole ice cap always grows in winter and shrinks in the summer. The average minimum area from 1979, when precise satellite mapping began, until 2000 was 11 million square kilometers. The new summer low, measured 11 days ago, was 20 per cent below that.
This is the fourth consecutive year that melting has been greater than average, and it pushed the overall decline in sea ice per decade to 8 per cent, up from 6.5 per cent in 2001.
Walt Meier, also at the Colorado centre, said: "Having four years in a row with such low ice extents has never been seen before in the satellite record. It clearly indicates a downward trend, not just a short-term anomaly."
Surface air temperatures over most of the Arctic Ocean often have been 2-3 degrees higher this year than from 1955 to 2004.
The notorious north-west passage through the Canadian Arctic from Europe to Asia was completely open this summer, except for a 95-kilometre swathe of scattered ice floes. The north-east passage, north of the Siberian coast, has been ice-free since August 15.
Springtime melting in the Arctic has begun much earlier in recent years. This year it started 17 days earlier than expected. The winter rebound of ice, where sea water refreezes, has also been affected. Last winter's recovery was the smallest on record and the peak Arctic ice cover failed to match the previous year's level.
The decline threatens wildlife in the region, especially polar bears. It is also the latest in a series of discoveries that have raised the spectre of environmental tipping points: critical thresholds beyond which the climate would be unable to recover.














































































GRAVITATION..

One consequence of the new theory of relativity meant of course that Newton's theory of gravitation was no longer relative to inertial observers moving relative to each other either. This meant that a new theory of gravitation had to be found which would be relative according to the special theory of relativity. Now a basic tenet of Newtonian relativity is the concept of absolute space. According to Newton there was an absolute space that did not change or alter and did not care about the state of the observer. The experiment that led him to this conclusion was one he performed himself. He strung a bucket full of water with a rope. He rotated the bucket so the rope was twisted and then let it go. The bucket started spinning around. The water level of course is flat when the bucket starts to spin. Then gradually the water starts to pick up the rotation from the bucket. Eventually the water is rotating at the same speed as the bucket. At this point the surface of the water is curved into a parabola. When the bucket was moving relative to the water the level was flat. It was only when water wasn't moving relative to the bucket that the surface became curved. So Newton concluded it wasn't the motion of the bucket that changed the surface of the water, because by the time the surface of water was affected the water wasn't moving relative to the bucket anymore, but that it was the motion of the water itself which was significant. Somehow the water was aware of the fact that it was in rotation. And so Newton concluded that there was an absolute space that decided what did and didn't have a force acting on it. And only observers at rest or in uniform motion relative to that absolute space could be inertial observers.
Ernst Mach, an Austrian physicist who worked in the end of the last century disagreed with Newton's interpretation of the bucket experiment. He held that all knowledge was derived from sensations. So he refused to admit any statement in natural science that wasn't empirically verifiable. This led him to dismiss Newton's absolute space. He argued instead that the water was responding the mass around it, like the Earth, that it was rotating relative to. As he pointed out, the bucket was of small mass, but if it was made ``several leagues thick'' no one was competent to say how the water would react. His theory of relativity thus did not allow any absolute space. Inertial observers in his theory were at rest or in uniform motion relative to some space that was defined by all the material in the Universe.
This new statement of relativity strongly influenced Einstein while he was developing his theory of gravity. He postulated the strong principle of equivalence. According to this principle, in the presence of a gravitational field (say on Earth or around Sun), at each point it is possible over a small volume to define an observer for whom the laws of physics are identical to that of an unaccelerated observer (i.e., an observer who has no forces acting on him/her). Thus in some ways Einstein's theory of gravity falls in between Machian and Newtonian relativity. The material around our small volume of interest does define the frame identical to the unaccelerated frame (as far as physical laws go), but once that frame is defined the details of the mass distribution no longer matter for the entire small volume.
Stating the equivalence principle in this way brings it very close to a different field that had been worked on before at some length. Imagine a curved line. If we magnify a small portion of it, it looks less curved. We can continue our focusing into smaller and smaller sections of the curved line. Eventually we'll be looking at such a small portion of the curved line that it will look straight to us, much like the way the Earth seems flat at close range even though we know that it is spherical. Note how close this is to the idea that in a small enough volume about a point in a gravitational field we can define a frame where we can forget that there is a gravitational field. This analogy led Einstein to conclude that the gravitational field was infact a statement about the geometry of space-time itself. The presence of massive objects like the Sun causes space time to curve like the surface of the Earth is curved. The curvature of space time is much harder to visualize than the curved surface of a balloon or earth of course. The Earth is a two dimensional curved surface occupying a three dimensional volume. Its far harder to imaging a curved three or four dimensional volume. Regardless the mathematics is very similar and it is possible to carry over the same mathematical arguments from curved two dimensional surfaces to higher dimensions. In the absence of mass the geometry of space time is flat, in the way the table top is a flat two dimensional surface. When there is mass present the space time curves to act like the surface of Earth or the surface of water in the rotating bucket. Except that the curved ``surface'' is in four dimensions (three space dimensions and one time) rather than two. As is to be expected, indeed is required, the Einstein's theory of gravity reduces to Newtonian gravity when the gravitational field involved is not very intense, like in the solar system. Which is necessary given the wonderful successes of Newtonian gravity in explaining the motions of planets. Newtonian gravity fails at Mercury, closest to Sun, where the gravitational field is the most intense. And there the corrections made by Einstein's gravity match with observations perfectly. The unexplained fast precession of Mercury is exactly what is to be expected once corrections due to Einstein's theory of gravity is taken into account.
Some consequences of Einstein's theory of gravity fall straight out of the basic propositions. Because the presence of mass curves space time, ``straight lines'' are no longer straight in the way we think of them in flat space time. Imagine two people back to back on the North Pole starting to walk out in what they think are straight lines. If the Earth were flat they would never meet. Of course we know that that won't be the case and they will meet face to face at the South Pole. This is drastically different from what we learnt in Euclidean geometry where parallel lines never meet and a straight line extends out in two directions infinitely. Whereas in curved space they turn around and meet. Similarly in curved space time ``straight lines'' behave strangely. Two rays of light for example that are parallel in a flat space time would carry on parallel to each other never reducing or increasing the distance to each other. In curved space time they would change the distance between each other. This was observed by Sir Arthur Eddington when he looked for stars near the Sun during a complete solar eclipse and found that they were in different positions to where they were when the Sun was in a different part of the sky. This meant that the light rays reaching us from the stars had been bent by the curved space time due to the Sun's mass.
Another consequence that follows from the equivalence principle is the dilation of time. Imagine two points in a gravitational field, say the Earth and the Pluto in the Sun's gravitational field. According to the strong equivalence principle around each point there is a small volume where we can define an observer (inertial observer) where the physical laws are the same as an un-accelerated observer. But the volume must be small. So the observer who is inertial in the small volume around Pluto won't appear inertial on Earth at all. Imagine a clock in the hand of this observer on Pluto. It will work according to the time scale the inertial observer at Pluto thinks is appropriate. This won't be appropriate at all to the inertial observer at the Earth. So the identical clock on Earth will run differently from the clock on Pluto. In fact as we get closer to Sun, i.e., as the gravitational field intensifies the clock ticks slower compared to what it would in the absence of the Sun. Of course sitting on Earth we can't tell that it is ticking slower, because our standards of time (like how fast we grow old, etc.) are also slowed (remember all physical laws are affected). But if we were to compare clocks in Pluto and Earth we would be able to tell the difference. In fact this is what happens when we look at an atom radiating light. This is a natural clock and consequently will run slower on Earth than on Pluto. As the photon is radiated on Earth it has the color appropriate to the difference of energies of the stationary states the atom is making the transition between. But because of the difference in ticks of the clocks on Pluto the color will appear inappropriate for the same transition. It will appear redder on Pluto where gravity due to Sun is less intense than on Earth. This is called gravitational redshift and has been observed for light coming from white dwarves which have an intense gravitational field.
There are other theories of gravity as well, some not as elegant as Einstien's theory, others of comparable elegance. However the final word in science comes not from prejudices about heuristics but empirical evidence. And from that point of view, Einstein's theory is far ahead of its nearest competitors. But it continues to be challenged by observational tests. One of the most interesting ones being done today involves a yet unobserved prediction of the theory. Just as Maxwell's theory of Electromagnetic fields predicted the presence of waves, later identified as light, Einstein's theory for gravitational fields predict the presence of gravitational waves. However these are extremely difficult to observe and require sensitivity that is yet to be achieved with current technology. However there already exists indirect evidence through pulsars that have been observed to be slowing down because of energy radiated out in gravitational waves. These observations led to Nobel prizes for Joseph Taylor and Russell Hulse. However efforts continue to directly detect these waves in the geometry of the very space time we exist in.









THE BIG BANG THEORY









Big Bang Theory, currently accepted explanation of the beginning of the universe. The big bang theory proposes that the universe was once extremely compact, dense, and hot. Some original event, a cosmic explosion called the big bang, occurred about 10 billion to 20 billion years ago, and the universe has since been expanding and cooling.
The theory is based on the mathematical equations, known as the field equations, of the general theory of relativity set forth in 1915 by Albert Einstein.In 1922 Russian physicist Alexander Friedmann provided a set of solutions to the field equations. These solutions have served as the framework for much of the current theoretical work on the big bang theory. American astronomer Edwin Hubble provided some of the greatest supporting evidence for the theory with his 1929 discovery that the light of distant galaxies was universally shifted toward the red end of the spectrum. This proved that the galaxies were moving away from each other. He found that galaxies farther away were moving away faster, showing that the universe is expanding uniformly. However, the universe's initial state was still unknown.
In the 1940s Russian American physicist George Gamow worked out a theory that fit with Friedmann's solutions in which the universe expanded from a hot, dense state. In 1950 British astronomer Fred Hoyle, in support of his own opposing steady-state theory, referred to Gamow's theory as a mere "big bang," but the name stuck. Indeed, a contest in the 1990s by Sky & Telescope magazine to find a better (perhaps more dignified) name did not produce one.