2010. június 30., szerda
2010. június 25., péntek
2010. június 15., kedd
könnyebb annak álmodni a tulajdonmentességről, aki nem él volt kommunista országban, aki nem tapasztalta meg, hogy az emberek többsége mennyire ragaszkodik a tárgyaihoz, így nem kételkedik saját képességében, hogy lemondjon bármilyen jellegű tulajdonformálásról? talán könnyebb, talán meg sem fordul a fejében, hogy ilyen gondolatokkal tornáztassa az agyát
a családom fényképeit például nagyon nehezen tudnám kiengedni az 'enyém' fogalomkörből, a naplóimat ugyanúgy.. szép álom elképzelni egy olyan társadalmat, ahol mindenki jóindulatú, minden közös, ha létrehoznak valamit, az minden egyes ember számára létezik, gyakorlatba való átvitele azonban rengeteg generációt, és az emberi természetet tiszteletben tartó, ugyanakkor fejleszteni próbáló nevelést igényel
jelenleg sokkal több a korlátozott műveltségű és intellektuális képességű ember, mint azok, akik rendelkeznek a megfelelő tudásszinttel és a felhasználói képességgel, emellett az utóbbi kategória is feloszlik a helyzetbe beletörődő és saját érdekét követőkre, valamint a konstruktív változások fele irányulókra
a mindennap tortát evő gyermeknek nehéz szívvel tiltja meg az ember, hogy káros mennyiségű cukrot vigyen a szervezetébe, hiszen annyira jól esik neki, és nem érti, miért nem szabad olyasmit tegyen, ami számára kellemes.. egy ideig próbálhatjuk mindenféle mozgásos tevékenységekbe bevonni, hogy szervezete elégesse a felesleget, de be kell látnunk, hogy bármennyire is szenvedjen tőle, kevesebb az a szenvedés, amit most a lemondás okoz, mint amit később kellene átéljen, amikor fellépnek a túlzott édességélvezet romboló hatásai
bízok az emberiség morális fejlődőképességében, és bízok abban, hogy egy napon nem lesz szükséges bármit is tiltani, hogy megvédjük önmaguktól az embereket
a családom fényképeit például nagyon nehezen tudnám kiengedni az 'enyém' fogalomkörből, a naplóimat ugyanúgy.. szép álom elképzelni egy olyan társadalmat, ahol mindenki jóindulatú, minden közös, ha létrehoznak valamit, az minden egyes ember számára létezik, gyakorlatba való átvitele azonban rengeteg generációt, és az emberi természetet tiszteletben tartó, ugyanakkor fejleszteni próbáló nevelést igényel
jelenleg sokkal több a korlátozott műveltségű és intellektuális képességű ember, mint azok, akik rendelkeznek a megfelelő tudásszinttel és a felhasználói képességgel, emellett az utóbbi kategória is feloszlik a helyzetbe beletörődő és saját érdekét követőkre, valamint a konstruktív változások fele irányulókra
a mindennap tortát evő gyermeknek nehéz szívvel tiltja meg az ember, hogy káros mennyiségű cukrot vigyen a szervezetébe, hiszen annyira jól esik neki, és nem érti, miért nem szabad olyasmit tegyen, ami számára kellemes.. egy ideig próbálhatjuk mindenféle mozgásos tevékenységekbe bevonni, hogy szervezete elégesse a felesleget, de be kell látnunk, hogy bármennyire is szenvedjen tőle, kevesebb az a szenvedés, amit most a lemondás okoz, mint amit később kellene átéljen, amikor fellépnek a túlzott édességélvezet romboló hatásai
bízok az emberiség morális fejlődőképességében, és bízok abban, hogy egy napon nem lesz szükséges bármit is tiltani, hogy megvédjük önmaguktól az embereket
2010. június 14., hétfő
How Did Life Arise on Earth?
Earth is estimated to be about 4.5 billion years old, and for much of that history it has been home to life in one weird form or another.
The earliest evidence for life on Earth comes from fossilized mats of cyanobacteria called stromatolites in Australia that are about 3.4 billion years old. Ancient as their origins are, these bacteria (which are still around today) are already biologically complex—they have cell walls protecting their protein-producing DNA, so scientists think life must have begun much earlier, perhaps as early as 3.8 billion years ago.
Today, there are several competing theories for how life arose on Earth. Some question whether life began on Earth at all, asserting instead that it came from a distant world or the heart of a fallen comet or asteroid. Some even say life might have arisen here more than once.
Most scientists agree that life went through a period when RNA was the head-honcho molecule, guiding life through its nascent stages. According to this "RNA World" hypothesis, RNA was the crux molecule for primitive life and only took a backseat when DNA and proteins—which perform their jobs much more efficiently than RNA—developed.
RNA is very similar to DNA, and today carries out numerous important functions in each of our cells, including acting as a transitional-molecule between DNA and protein synthesis, and functioning as an on-and-off switch for some genes.
Like DNA, RNA is a complex molecule made of repeating units of thousands of smaller molecules called nucleotides that link together in very specific, patterned ways.
Suppose, Dawkins says, the universe contains a billion billion planets (a conservative estimate, he says), then the chances that life will arise on one of them is not really so remarkable.
Furthermore, if, as some physicists say, our universe is just one of many, and each universe contained a billion billion planets, then it's nearly a certainty that life will arise on at least one of them.
Robert Shapiro, a chemist at New York University thinks life started with molecules that were smaller and less complex than RNA, which performed simple chemical reactions that eventually led to a self-sustaining system involving the formation of more complex molecules.
The earliest evidence for life on Earth comes from fossilized mats of cyanobacteria called stromatolites in Australia that are about 3.4 billion years old. Ancient as their origins are, these bacteria (which are still around today) are already biologically complex—they have cell walls protecting their protein-producing DNA, so scientists think life must have begun much earlier, perhaps as early as 3.8 billion years ago.
Today, there are several competing theories for how life arose on Earth. Some question whether life began on Earth at all, asserting instead that it came from a distant world or the heart of a fallen comet or asteroid. Some even say life might have arisen here more than once.
Most scientists agree that life went through a period when RNA was the head-honcho molecule, guiding life through its nascent stages. According to this "RNA World" hypothesis, RNA was the crux molecule for primitive life and only took a backseat when DNA and proteins—which perform their jobs much more efficiently than RNA—developed.
RNA is very similar to DNA, and today carries out numerous important functions in each of our cells, including acting as a transitional-molecule between DNA and protein synthesis, and functioning as an on-and-off switch for some genes.
Like DNA, RNA is a complex molecule made of repeating units of thousands of smaller molecules called nucleotides that link together in very specific, patterned ways.
Suppose, Dawkins says, the universe contains a billion billion planets (a conservative estimate, he says), then the chances that life will arise on one of them is not really so remarkable.
Furthermore, if, as some physicists say, our universe is just one of many, and each universe contained a billion billion planets, then it's nearly a certainty that life will arise on at least one of them.
Robert Shapiro, a chemist at New York University thinks life started with molecules that were smaller and less complex than RNA, which performed simple chemical reactions that eventually led to a self-sustaining system involving the formation of more complex molecules.
New Theory for Life's First Energy Source
An obscure compound known as pyrophosphite could have been a source of energy that allowed the first life on Earth to form, scientists now say.
From the tiniest bacteria to the complex human body, all living beings require an energy-transporting molecule called ATP to survive. Often likened to a "rechargeable battery," ATP stores chemical energy in a form that can be used by organic matter.
"You need enzymes to make ATP, and you need ATP to make enzymes," said researcher Terence Kee of the University of Leeds in England. "The question is: Where did energy come from before either of these two things existed? We think that the answer may lie in simple molecules, such as pyrophosphate, which is chemically very similar to ATP, but has the potential to transfer energy without enzymes."
Obscure but important
Prior theories for how life emerged from mere chemistry have considered that a similar but separate compound known as pyrophosphate was the predecessor to the more complex yet more efficient ATP.
Phosphate has 4 oxygen atoms bound to a central phosphorus atom, and is present in all living cells. When two phosphates combine and lose a water molecule, they form pyrophosphate.
From the tiniest bacteria to the complex human body, all living beings require an energy-transporting molecule called ATP to survive. Often likened to a "rechargeable battery," ATP stores chemical energy in a form that can be used by organic matter.
"You need enzymes to make ATP, and you need ATP to make enzymes," said researcher Terence Kee of the University of Leeds in England. "The question is: Where did energy come from before either of these two things existed? We think that the answer may lie in simple molecules, such as pyrophosphate, which is chemically very similar to ATP, but has the potential to transfer energy without enzymes."
Obscure but important
Prior theories for how life emerged from mere chemistry have considered that a similar but separate compound known as pyrophosphate was the predecessor to the more complex yet more efficient ATP.
Phosphate has 4 oxygen atoms bound to a central phosphorus atom, and is present in all living cells. When two phosphates combine and lose a water molecule, they form pyrophosphate.
2010. június 11., péntek
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