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一个有趣的故事

一个有趣的故事# Joke - 肚皮舞运动

o*y2019-06-17 07:06

1 楼

大本送钱来了，多拿几个麻袋接着哦。

x52019-06-17 07:06

2 楼

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expert (老猫咪@毛毛的爹) 于 (Sat Mar 3 21:43:23 2012, 美东) 提到:
请万佛轻拍
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ijnbhu8 (ijnbhu8(我是懒洋洋）) 于 (Sat Mar 3 21:43:51 2012, 美东) 提到:
排包子
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gongren (gongren) 于 (Sat Mar 3 21:44:49 2012, 美东) 提到:
大师, 包子
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expert (老猫咪@毛毛的爹) 于 (Sat Mar 3 21:45:27 2012, 美东) 提到:
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gongren (gongren) 于 (Sat Mar 3 21:47:20 2012, 美东) 提到:
这个牛吃草拍的很好....
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xjack (xjack) 于 (Sat Mar 3 21:49:53 2012, 美东) 提到:
哪有牛吃草？
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gongren (gongren) 于 (Sat Mar 3 21:51:07 2012, 美东) 提到:
老猫的牛居然吃完了还往回走的
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expert (老猫咪@毛毛的爹) 于 (Sat Mar 3 21:51:14 2012, 美东) 提到:
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x5 (买时多流汗，卖时少流血) 于 (Sat Mar 3 21:52:10 2012, 美东) 提到:
挖，转正了？
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ijnbhu8 (ijnbhu8(我是懒洋洋）) 于 (Sat Mar 3 21:59:20 2012, 美东) 提到:
这个星星点点的是咋拍出来的？
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expert (老猫咪@毛毛的爹) 于 (Sat Mar 3 22:01:14 2012, 美东) 提到:
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xjack (xjack) 于 (Sat Mar 3 22:01:55 2012, 美东) 提到:
别对上焦就行
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ijnbhu8 (ijnbhu8(我是懒洋洋）) 于 (Sat Mar 3 22:22:05 2012, 美东) 提到:
谢谢 x和猫大师 lol
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dealwithyou (第二位自由) 于 (Sat Mar 3 22:29:14 2012, 美东) 提到:
D,DW,DS,XXL
BZ
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wenkan (文侃) 于 (Sat Mar 3 22:31:57 2012, 美东) 提到:
娃不错
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redskeleton (红骨架) 于 (Sat Mar 3 22:44:24 2012, 美东) 提到:
第一张，把鞋和字母都拍全会不会好一点？
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VaLintine (Lin) 于 (Sat Mar 3 22:49:19 2012, 美东) 提到:
焦点在E上是不是...
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nbnb (自强不息厚德载物) 于 (Sat Mar 3 23:09:45 2012, 美东) 提到:
扫街的好地方还不拍拍路人？
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gongren (gongren) 于 (Sat Mar 3 23:10:42 2012, 美东) 提到:
母猫在旁边吧
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nbnb (自强不息厚德载物) 于 (Sat Mar 3 23:11:58 2012, 美东) 提到:
用超广
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expert (老猫咪@毛毛的爹) 于 (Sat Mar 3 23:18:16 2012, 美东) 提到:
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nbnb (自强不息厚德载物) 于 (Sat Mar 3 23:19:51 2012, 美东) 提到:
没事，没人care
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gongren (gongren) 于 (Sat Mar 3 23:20:31 2012, 美东) 提到:
土了吧, 把女儿放在前面, 然后镜头越过女儿
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carbonplay (~~ 贪玩) 于 (Sat Mar 3 23:21:21 2012, 美东) 提到:
路人有啥好拍的，
天天上下班，都是无恙无恙的路人
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daye520 (哈哈) 于 (Sat Mar 3 23:21:38 2012, 美东) 提到:
nyc就是个旅游景点，街上随便拍就是了
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redskeleton (红骨架) 于 (Sat Mar 3 23:26:16 2012, 美东) 提到:
用鱼眼。。。
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nbnb (自强不息厚德载物) 于 (Sat Mar 3 23:30:42 2012, 美东) 提到:
稀罕啊，我们这儿街上没人。
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vilta (miovilta) 于 (Sat Mar 3 23:31:18 2012, 美东) 提到:
天天叫的辣妹哪里来？
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nbnb (自强不息厚德载物) 于 (Sat Mar 3 23:40:15 2012, 美东) 提到:
啥？没有拉美。
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carbonplay (~~ 贪玩) 于 (Sat Mar 3 23:43:24 2012, 美东) 提到:
有啥稀罕的，和国内一样啊，人挤人的
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nbnb (自强不息厚德载物) 于 (Sun Mar 4 00:03:51 2012, 美东) 提到:
好啊，回头用xpan试试。
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bmwcar (也————) 于 (Sun Mar 4 01:08:38 2012, 美东) 提到:
我经常用长焦偷拍美女
拍回来给老婆看
老婆有时候夸好看，又时候骂我怎么这么没品位
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NovSep (NovSep) 于 (Sun Mar 4 01:24:39 2012, 美东) 提到:
恩娃好

H*g2019-06-17 07:06

3 楼

关于最早怎么发现DNA用三联密码子编码蛋白质的。这个问题我最近也想过，当时那个
条件，是怎么把这种事情搞清楚的呢？
http://nautil.us/issue/72/quandary/the-thrill-of-defeat-rp
原文很长，抄几段：
Before the early 1950s, Brenner told me, many scientists “thought that
proteins were sort of fuzzy polymers,” just patterns of beads that repeated
or had undefined sequences. But by 1953, proteins were found to have
defined sequences of beads, and DNA looked like a secret code built from
four letters: A, T, G, and C. Each gene in DNA seemed to be an instruction
set for assembling a protein’s beads in the right order. The big question
was, how?
1950年代之前，很多人认为蛋白质就是一种乱七八糟的高聚物。但是到了1953年，发现
蛋白质是由序列的，而且DNA，因为有ATCG四种碱基，看上去像种编码系统。
The four letters of the DNA code clearly couldn’t stand for just one amino
acid each, because together they could then encode no more than four of the
20 kinds of amino acids. Using two letters in succession instead—AT, AG, AC
, TA, and so on—gave just 16 possible combinations, also too few. Three
letters gave 64 combinations, more than needed to make 20 amino acids. So
three letters was likely to be a minimum word size in the DNA, but four or
more letters was possible too.
四种碱基显然不会是跟20种氨基酸一一对应的，假如两个两个的来，也只能编出16个氨
基酸，三个的话就有64种了。但是谁知道会不会用四个或者更多个来编码呢？
Take a look at how hard it would be to solve the code for a protein, insulin
in this case, even if you knew what the DNA and the protein sequences
looked like. Here’s a fragment of insulin’s protein sequence:
Goldstein_BREAKER_BEADS
Today, we know that insulin’s DNA sequence looks like this:
比如一段胰岛素序列是这样的
TTCGTCAACCAGCATCTGTGTGGCTCCCACCTGGTGGAGGCGCTGTACCTGGTGTGCGGA
（翻译出来是 F V N Q H L C G S H L V E A L Y L V C G ）
Even with this knowledge, it’s a huge challenge to decode how to get from
the DNA to the protein. And in 1953, nobody knew this DNA sequence—nor any
DNA sequence for that matter.
即便知道了dna序列和蛋白质序列，要搞清楚这个编码系统也是个巨大挑战。而且1953
年的时候，其实谁也不知道这个胰岛素DNA序列，或者任何一个DNA序列。
That didn’t stop people from trying to crack the code. The theoretical
physicist George Gamow suggested that each amino acid bead might fit tightly
into diamond-shaped holes along the middle of the DNA double helix. DNA, he
thought, could serve as a physical template for stringing beads in the
right order, like a row of peg holes for different shaped pegs. The
dimensions were about right, and it happens that DNA’s four letters define
exactly 20 kinds of these holes.
不过科学家就喜欢超前占坑。一个理论物理学家George Gamow说，每个氨基酸可能可以
直接跟DNA双螺旋正中间的空腔配上形状，于是DNA分子就直接成了蛋白质的物理模板。
氨基酸的大小正好可以塞到DNA中间空出来的地方，而且DNA的四种碱基正好可以配出20
种不同形状的空腔
But neither Brenner nor Crick thought Gamow’s code could work, “because
first of all he was reading things both ways,” said Brenner. DNA has a
direction, something Gamow ignored or didn’t understand. By September 1956
Brenner discovered that Gamow’s solution couldn’t be correct, by showing
that it would prevent certain amino acids from being neighbors.
但是Brenner和克里克都不觉得Gamow的理论是对的。“首先，因为他读DNA不分方向，
”Brenner说。到了1956年九月，Brenner已经发现Gamow的理论不可能对，因为他的理
论会导致某些实际上相邻的氨基酸没法连在一起。

b*k2019-06-17 07:06

4 楼

低利率到2014年底觉得这消息已经够好的了，
QE这种大杀器这种时候还没必要上

H*g2019-06-17 07:06

5 楼

Although Gamow was wrong, his idea stirred Brenner and Crick’s imaginations
. Gamow thought like a cryptographer, in terms of information and codes,
which was new to most life scientists at the time. The hundreds of
biochemists who studied how proteins were made “were only interested in
where the energy of the peptide bond comes from,” Brenner told me. Crick
and Brenner, spurred by Gamow, started instead to think in terms of
information transfer.
尽管Gamow的理论不对，他的想法还是启发了Brenner和克里克。Gamow的思路接近一个
密码学家，他从信息和编码的角度来思考。当时大部分生化学家根本没这个思维方式。
Brenner说，当时的大部分蛋白质生化学家，“只关心形成蛋白质的肽键的能量从哪里
来”。于是Brenner和克里克开始从信息传递的角度琢磨这个问题。
This led to some clever ideas. In February 1957, Crick suggested how the
machinery inside us that reads DNA might know where each word in a DNA
sequence stops and the next one starts. Even without spaces or punctuation,
an English sentence made of 3-letter words like “Theboyatepieandham” is
decipherable to us. That’s not just because it contains words that make
sense, but also because we find only nonsense words if we start in the wrong
place and count off three letters at a time. Crick proposed that in the DNA
code, there might exist special “sense” words, which could dictate a
reading frame to the protein-making machinery.
到了1957年2月，克里克提出一种理论，解释读取DNA的结构可能如何知道从什么地方开
始，什么地方结束。比如，即便没有标点也没有空格，“Theboyatepieandham”这个三
字母词汇组成的英文句子，其实也是可以读懂的。这不仅因为这句话里只有有意义的词
，而且连起来有意思，而且因为假如我们从错误的地方开始三个三个地读，就只能看到
无意义的词。克里克提出，在DNA编码里，可能存在特殊的“有意义”的词，它们组成
的阅读框架可以被蛋白质合成机构读出来。
Crick reasoned that some combinations of letters couldn’t possibly serve as
sense words. For example, an amino acid specified by AAA wouldn’t work
because two such words in a row, AAAAAA, would make the reading frame
impossible to find. To build a set of possible three-letter words from just
A, T, G, and C, a colleague of Crick’s calculated that not just AAA but 43
more of the 64 possible three-letter combinations would need to be excluded
as nonsense words—leaving exactly 20 possible three-letter words, the magic
number of amino acids. It was a promising and clever solution, but it
turned out to be wrong. We know now that almost all words are sense words,
including words made of repeating letters. Proposals like this one, though,
were instrumental in shaping clear questions about the code.
克里克还说，某些组合可能不能形成有意义的词。例如假如AAA编码一个氨基酸的话，
那AAAAAA就会导致没法直接从里面找到阅读框架。从这个想法出发，克里克的一个同
事计算了一下，发现除了AAA之外，还有43个三联子会导致同样的问题。64-44=20。正
好20个氨基酸。这个想法确实很聪明。只可惜是错的。现在我们知道实际上64个三联组
合都是密码子。但是这个想法对后来的正确解答显然启发作用重大。

o*y2019-06-17 07:06

6 楼

没必要，其他国家在QE，美国在吸他们的血

【在 b**********k 的大作中提到】

: 低利率到2014年底觉得这消息已经够好的了，
: QE这种大杀器这种时候还没必要上

H*g2019-06-17 07:06

7 楼

In 1958, Brenner thought of a way to move from theoretical proposals to
tinkering directly with DNA. Thinking about a colleague’s results on DNA
viruses, he made a prescient guess that a bright yellow dye called proflavin
might produce single-letter deletions or additions in DNA, and that these
might knock the reading of DNA out of frame. If the reading frame mattered,
then the protein produced would make no sense—think “The boy ate pie and
ham” becoming “Heb oya tep iea ndh am.” He and Crick started working
together in the lab, growing DNA viruses on petri plates. The viruses would
infect bacteria, leaving a characteristically sized hole on a lawn of
bacteria when the protein in the DNA virus was working properly—if the
change in the DNA hadn’t disabled the resulting protein. “That you can
predict from these holes things about the internal structure of DNA,”
Brenner told me, “has always seemed to me to be remarkable.”
1958年，从一个同事的DNA病毒的实验结果，Brenner想到了一个主意。一种黄色燃料
proflavin可以造成单碱基插入或者删除。假如前面说到的“阅读框架”很重要，那这
样就会导致阅读出错。于是他和克里克开始做实验。这个实验是用一种细菌的病毒（噬
菌体）。先把细菌养在琼脂培养基上，会形成均匀的肉眼可见的一层苔。然后放上病
毒，有活病毒的地方细菌被啃死了，细菌苔上就形成一个个的洞。假如他们对病毒
DNA引入的变化导致蛋白质变化，那病毒就没活性了，细菌苔上的洞洞就没了。后来
Brenner说“你可以从这些洞洞来推测DNA的内部结构，这件事这总是叫我觉得很厉害”

Brenner and Crick combined mutants and found that most of the dye-induced
mutants could be suppressed by certain of the other dye-induced mutants.
Reasoning that the dye had sometimes added a letter and sometimes deleted a
letter, they started calling the changes “+” and “-”, which they had to
assign randomly since knowing which was which was impossible. Combining +
with - often reverted the viruses back to normal, as if this restored a
normal reading frame by gaining and losing a letter in the same stretch of
sequence, whereas combining + with + or - with - never did.
他们俩又把不同的突变组合起来，发现有些突变的效果总是能被另一些突变克服。他们
认为这说明一些删掉的碱基可以被插入的碱基救回来。他们把一些叫做+，另一些叫做-
。 +和-配对经常能起作用，但是 +和+ 以及 -和- 是不行的。
The results were making sense. If their theory was right, then Brenner and
Crick were on track toward finally breaking the code. They couldn’t read
individual letters in the DNA, but after eight years of work, it looked as
if they could at least change letters in predictable ways. Brenner worked
night and day. Crick, who rarely did experiments, became consumed by them
too, on some days walking back from the lab through Cambridge to visit his
home only for meals and to sleep.
这些结果有点意思了。假如他们的理论正确，那Brenner和克里克至少在正确的道路上
。他们还不能读直接DNA的碱基，但是他们八年的工作至少可以说允许他们对DNA做些可
以预测的修饰。Brenner像当代千老一样日夜辛劳。克里克基本不做实验，但是也全心
投入这些工作，有些时候全天呆在剑桥的实验室里，仅仅回家去吃饭和睡觉。
Then the surprise came.
然后出大事了

H*g2019-06-17 07:06

8 楼

In August 1961, more than 5,000 scientists came to Moscow for five days of
research talks at the International Congress of Biochemistry. A couple of
days in, Matt Meselson, a friend of Crick’s, told him the news: The first
word of the genetic code had been solved, by somebody else. In a small
Friday afternoon talk at the Congress, in a mostly empty room, Marshall
Nirenberg—an American biochemist and a complete unknown to Crick and
Brenner—reported that he had fed a single repeated letter into a system for
making proteins, and had produced a protein made of repeating units of just
one of the amino acids. The first word of the code was solved. And it was
clear that Nirenberg’s approach would soon solve the entire code.
1961年八月，5000多科学家聚集莫斯科国际生化大会。开了几天会之后，克里克一个
叫Matt Meselson的朋友告诉他，第一个遗传密码子被解读了。一个不起眼的周五下午
，在一个几乎空着的会议室里，Marshall Nirenberg，一个克里克和Brenner根本不知
道名字的美国生化学家，说他已经把一个只含有重复的碱基序列放到一个系统里，翻译
出一个只含有一种重复的氨基酸的蛋白质。于是这个重复的碱基显然编码这个氨基酸。
于是第一个遗传密码子被发现了。显然Nirenberg的方法很快就可以把其他密码子搞
清楚。
Here’s where I like to imagine what I would have done if I were Crick. For
someone driven solely by curiosity, Nirenberg’s result was terrific news:
The long-sought answer was arriving. The genetic code would be cracked. But
for someone with the human urge to attach one’s name to discoveries, the
news could not have been worse. Much of nearly a decade’s worth of Crick
and Brenner’s work on the coding problem was about to be made redundant.
对于真的“由于兴趣”搞科研的人，Nirenberg的报告显然是个极好消息。总算知道问
题的答案了。但是对于想把自己的名字和某个科学事件连起来的人，这显然是极不好的
消息。克里克和Brenner几乎10年的工作都成了多余的。
I’d like to believe I would have reacted honorably. I wouldn’t have
explained away Nirenberg’s finding to myself, concocting reasons why it
wasn’t convincing. I wouldn’t have returned to my lab and worked a little
faster to publish my own work sooner. I’ve seen scientists react like this
to competition. I’d like to believe that I would have conceded defeat and
congratulated Nirenberg. Of course, I’ll never know what I would have done.
xxx老师会这样做：。。。
Crick’s response was, to me, remarkable and exemplary. He implored
Nirenberg to give his talk again, this time to announce the result to more
than 1,000 people in a large symposium that Crick was chairing. Crick’s
Moscow meeting booklet survives as an artifact of his decision, with a hand-
written “Nirenberg” in blue ink, and a long arrow inserting into an
already-packed schedule the scientist who had just scooped him. And when
Nirenberg reached the stage, he reported that his lab had just solved a
second word of the code.
克里克的应对是：他要求Nirenberg 在自己主持的一个会场上对1000多个参与者重做这
个报告。克里克的莫斯科会议记录本现在还是个文物。在某一页上，一个蓝色钢笔写
的Nirenberg 和一个箭头插入到以及排满的议程中间。当Nirenberg 重做报告时，他
又加上了他的实验室刚刚又把第二个密码子给破解了。

H*g2019-06-17 07:06

9 楼

后面就全是赞美克里克的。完。