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People have always been fascinated by bats, but the scope of that interest generally is limited to how bats fly and their bizarre habit of sleeping upside down. Until now, no one had studied how bats arrive at their daytime perches.

A Brown University-led research team is the first to document the landing approaches of three species of bats - two that live in caves and one that roosts in trees. What they found was surprising: Not all bats land the same way.

"Hanging upside down is what bats do," said Daniel Riskin, a postdoctoral researcher in the Ecology and Evolutionary Biology department at Brown and main author on a paper reported in the Journal of Experimental Biology. "We've known this. But this is the first time anyone has measured how they land".

Using sophisticated motion capture cameras in a special flight enclosure, the team filmed each species of bat as it swooped toward a latticed landing pad and landed on it. Cynopterus brachyotis, a tree-roosting bat common in tropical parts of southeast Asia, executed a half-backflip as it swooped upward to the landing site, landing as its hind legs and thumbs touched the pad simultaneously - a four-point landing, the group observed.

The landing is hard, Riskin noted, with an impact force more than four times the species' body weight.........

I did'nt know that!!!!!!!

Hey guys may be u know this facts but i heard it for the first time and i foundthem quite interesting.......

1>Starfish don't have brains.

2>An ostrich's eye is bigger than its brain.

3>A crocodile cannot stick out its tongue.

4>The flea can jump 350 times its body length. That's like a human
jumping the length of a football field.

5>Some lions mate over 50 times a day.
(In my next life I still want to be a pig.
Quality over quantity, you know?)

i'm back

hey guys i'm back after a long time with some new infos. and yes MY XAMS R FINALLY OVER. Man these exams suck.

man i just came across a really idiotic joke. It says:Two Potato's are in an oven. The first turns to the other and says "Oh god! We're going to be cooked alive."

The other turns to him and replies, "Wow! A talking Potato."

Do you want to hear a Dirty Joke?

A White Horse fell into the Mud.

Dirty Joke!

God knows

Hey guys just help me out with this..... What happens after i complete the European campaign in "uefa euro 2008"????

The marimba

The marimba is a musical instrument in the percussion family. Keys or bars (usually made of wood) are struck with mallets to produce musical tones. The keys are arranged as those of a piano, with the accidentals raised vertically and overlapping the natural keys to aid the performer both visually and physically.

Modern marimba uses include solo performances, woodwind ensembles, marimba concertos, jazz ensembles, marching band (front ensembles), drum and bugle corps, and wind ensemble or orchestra compositions. Contemporary composers have utilized the unique sound of the marimba more and more in recent years, and it is common to find them in most new music for wind ensemble, although less so for orchestra. African marimba music sounds unique to North American audiences because most of the marimba music played in the Western Hemisphere has been South American. However, marimbas originated in Africa hundreds of years ago and were imported to South America in the sixteenth century. The original African sounds were incorporated into and changed by the music of the local cultures.

Part of the key to the marimba's rich sound is its resonators. These are metal tubes (usually aluminium) that hang below each bar, and the length varies according to the frequency that the bar produces. Vibrations from the bars resonate as they pass through the tubes, which amplify the tone in a manner very similar to the way in which the body of a guitar or cello would. In instruments exceeding 4½ octaves, the length of tubing required for the bass notes exceeds the height of the instrument. Some manufacturers, such as malletech, compensate for this by bending the ends of the tubes. Others, such as Adams and yamaha, expand the tubes into large box-shaped bottoms, resulting in the necessary amount of resonating space without having to extend the tubes. This is also achieved by custom manufacturer Marimba One by widening the resonators into an oval shape, with the lowest ones reaching nearly a foot in width, and doubling the tube up inside the lowest resonators. On many marimbas, decorative resonators are added to fill the gaps in the accidental resonator bank. In addition to this, the resonator lengths are sometimes altered to form a decorative arch, such as in the Musser M-250. This does not affect the resonant properties, because the end plugs in the resonators are still placed at their respective lengths.

The mammoth genome

Webb Miller from Pennsylvania State University together with a large team of American and Russian scientists has just published about 70% of the full mammoth genome. Currently, about 3.3 billion of those base pairs are known and Miller's group estimate that the full sequence would weigh in at about 4.7 billion base pairs, making it fairly... well... mammoth in size. If the estimate is right, the mammoth genome was about 40% larger than a human's but about the same size as a modern elephant's.

So we don't have a complete picture yet, but it's a major technical advance nonetheless. Sequencing ancient genomes is no easy task and just a few years ago, it would have been little more than a flight of fancy. The obstacles were numerous - traces of ancient DNA are hard to come by; when they are extracted, they are broken into tiny fragments and swamped by DNA from nearby bacteria and fungi; and the sequencing technology at the time simply wasn't fast enough.

The first two problems were actually solved by nature thousands of years ago. While fossilisation does little for preserving DNA, the freezing process that many mammoth carcasses were subjected to was much kinder. It safeguarded their hair, a rich source of DNA that is well protected from the damaging elements and the contaminating genes of microbes.

The final technological hurdle was leapt in 2005, with the advent of a new technique called 454 sequencing that was 100 to 1,000 times faster than the favoured method of the time. In the three years since, the method has become five times faster still and can now handle billions of base pairs in a single run, allowing individual laboratories to sequence in months what international collaborations used to take years to accomplish.

Miller's group leapt onto the new tool and mere months after the technology was available, the had used it to to sequence about 13 million base pairs of mammoth DNA, about 3% of its full genome. The team went on to sequence the DNA of the mammoth's mitochondria - small structures inside complex cells that contains its own mini-genome and accounts for just 13 of the mammoth's thousands of genes. It was an important step, but small potatoes compared to the much bigger task of sequencing its nuclear genome.

The dwarf planets

A dwarf planet is a celestial body which is too small to be considered a real planet but too large to be called a space rock. It must revolve around the sun and it should not be a satellite of another planet. Hence this disqualifies earth's big moon from being a dwarf planet.

Our solar system currently has three dwarf planets. These are Ceres, Pluto, and Eris. Ceres was the first dwarf planet discovered and at first was considered as a large asteroid. However this was later corrected after discovering that it had not only its own inner core, but a very thin atmosphere and gravity.

The second dwarf planet Pluto was first considered a small planet in itself but its orbit crosses the Kuiper Belt in the same way that Ceres moves among asteroids within the asteroid belt making Pluto a dwarf planet.

The last dwarf planet is Eris which is also the largest and coldest dwarf planet and was discovered in 2005 beyond the orbit of Pluto.

The dark side in the universe

Dark Matter

What do scientists look for when they search for dark matter? We cannot see or touch it: its existence is implied. Possibilities for dark matter range from tiny subatomic particles weighing 100,000 times less than an electron to black holes with masses millions of times that of the sun (9). The two main categories that scientists consider as possible candidates for dark matter have been dubbed MACHOs (Massive Astrophysical Compact Halo Objects), and WIMPs (Weakly Interacting Massive Particles). Although these acronyms are amusing, they can help you remember which is which. MACHOs are the big, strong dark matter objects ranging in size from small stars to super massive black holes (1). MACHOs are made of 'ordinary' matter, which is called baryonic matter. WIMPs, on the other hand, are the little weak subatomic dark matter candidates, which are thought to be made of stuff other than ordinary matter, called non-baryonic matter. Astronomers search for MACHOs and particle physicists look for WIMPs. Astronomers and particle physicists disagree about what they think dark matter is. Walter Stockwell, of the dark matter team at the Center for Particle Astrophysics at U.C. Berkeley, describes this difference. "The nature of what we find to be the dark matter will have a great effect on particle physics and astronomy. The controversy starts when people made theories of what this matter could be--and the first split is between ordinary baryonic matter and non-baryonic matter" (10). Since MACHOs are too far away and WIMPs are too small to be seen, astronomers and particle physicists have devised ways of trying to infer their existence.

The theory f relativity

Theory of Relativity - The Basics
The Theory of Relativity, proposed by the Jewish physicist Albert Einstein (1879-1955) in the early part of the 20th century, is one of the most significant scientific advances of our time. Although the concept of relativity was not introduced by Einstein, his major contribution was the recognition that the speed of light in a vacuum is constant and an absolute physical boundary for motion. This does not have a major impact on a person's day to day life since we travel at speeds much slower than light speed. For objects traveling near light speed, however, the theory of relativity states that objects will move slower and shorten in length from the point of view of an observer on Earth. Einstein also derived the famous equation, E = mc2, which reveals the equivalence of mass and energy. When Einstein applied his theory to gravitational fields, he derived the "curved space-time continuum" which depicts the dimensions of space and time as a two-dimensional surface where massive objects create valleys and dips in the surface. This aspect of relativity explained the phenomena of light bending around the sun, predicted black holes as well as the background radiation left from the Big Bang. For his work on relativity, the photoelectric effect and blackbody radiation, Einstein received the Nobel Prize in 1921.

Theory of Relativity - Inherent Limitations
For the past century, scientists have conducted a variety of experiments to verify the implications of the Theory of Relativity as well as advance fields such as cosmology and particle physics. However, there is some question as to the ability of Einstein's Theory of Relativity to describe as many physical phenomena as has been claimed - with some scientists arguing against it entirely. Regardless, as with any other scientific theory, it is not the absolute, entire and final description of the universe. Because it is a scientific theory, it contains certain assumptions and approximations of nature and ultimately, fails to describe several phenomena altogether (i.e. electromagnetism). Unfortunately, Einstein's Theory of Relativity, much like Darwin's Theory of Evolution, has become popularized as a "scientific truth" because it offers a simplified explanation to the complexity observed in the natural universe. In fact, Einstein himself spent the rest of his life attempting to develop a Unified Theory of Physics which would combine electromagnetism with relativity. He was unsuccessful and to date, this task has not been accomplished.

Theory of Relativity - Abused and Misused
In addition to being misrepresented as an undeniable fact, the Theory of Relativity has been misapplied to areas beyond gravitational phenomena even in the scientific community. Concerning the origin of the universe, Einstein's Theory of Relativity is the basis for the Big Bang Theory, a theory postulating on the origin of the universe. Likewise, Darwin's Theory of Evolution is a theory focused on the origin of species and, ultimately, the origin of man. Yet, these two theories are often discussed as though they are two ends of a larger unified theory. In reality, they are not theories on a continuum, but separate theories describing two completely different physical phenomena.

Additionally, Einstein's Theory is intended to describe physical laws of the universe alone, not philosophy or religion or God. For instance, the Theory of Relativity and the philosophical belief of moral relativism have nothing in common except for the term relative, yet some believe them to have common meanings. Some might argue that moral relativity - the belief that truth and lies, good and evil, God or other gods are determined and validated by an individual's personality, genetics, and environmental upbringing - is a consequence of Einstein's work.

The first atoms

Now that an attempt has been made to grapple with the theory of the Big Bang, the next logical question to ask would be what happened afterward? In the minuscule fractions of the first second after creation what was once a complete vacuum began to evolve into what we now know as the universe. In the very beginning there was nothing except for a plasma soup. What is known of these brief moments in time, at the start of our study of cosmology, is largely conjectural. However, science has devised some sketch of what probably happened, based on what is known about the universe today. Immediately after the Big Bang, as one might imagine, the universe was tremendously hot as a result of particles of both matter and antimatter rushing apart in all directions. As it began to cool, at around 10^-43 seconds after creation, there existed an almost equal yet asymmetrical amount of matter and antimatter. As these two materials are created together, they collide and destroy one another creating pure energy. Fortunately for us, there was an asymmetry in favor of matter. As a direct result of an excess of about one part per billion, the universe was able to mature in a way favorable for matter to persist. As the universe first began to expand, this discrepancy grew larger. The particles which began to dominate were those of matter. They were created and they decayed without the accompaniment of an equal creation or decay of an antiparticle. As the universe expanded further, and thus cooled, common particles began to form. These particles are called baryons and include photons, neutrinos, electrons and quarks would become the building blocks of matter and life as we know it. During the baryon genesis period there were no recognizable heavy particles such as protons or neutrons because of the still intense heat. At this moment, there was only a quark soup. As the universe began to cool and expand even more, we begin to understand more clearly what exactly happened. After the universe had cooled to about 3000 billion degrees Kelvin, a radical transition began which has been likened to the phase transition of water turning to ice. Composite particles such as protons and neutrons, called hadrons, became the common state of matter after this transition. Still, no matter more complex could form at these temperatures. Although lighter particles, called leptons, also existed, they were prohibited from reacting with the hadrons to form more complex states of matter. These leptons, which include electrons, neutrinos and photons, would soon be able to join their hadron kin in a union that would define present-day common matter. After about one to three minutes had passed since the creation of the universe, protons and neutrons began to react with each other to form deuterium, an isotope of hydrogen. Deuterium, or heavy hydrogen, soon collected another neutron to form tritium. Rapidly following this reaction was the addition of another proton which produced a helium nucleus. Scientists believe that there was one helium nucleus for every ten protons within the first three minutes of the universe. After further cooling, these excess protons would be able to capture an electron to create common hydrogen. Consequently, the universe today is observed to contain one helium atom for every ten or eleven atoms of hydrogen. While it is true that much of this information is speculative, as the universe ages we are able to become increasingly confident in our knowledge of its history. By studying the way in which the universe exists today it is possible to learn a great deal about its past. Much effort has gone into understanding the formation and number of baryons present today. Through finding answers to these modern questions, it is possible to trace their role in the universe back to the Big Bang. Subsequently, by studying the formation of simple atoms in the laboratory we can make some educated guesses as to how they formed originally. Only through further research and discovery will it be possible to completely understand the creation of the universe and its first atomic structures, however, maybe we will never know for sure. AGE OF THE UNIVERSE
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