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w*****r
发帖数: 7106 | 2 不告诉我我要给你翻译了哈.
Water, water, little spring rubbing broken. Helical wind day late goose back, hold Cup in hand Lanzhou drunk. Drunk, drunk, months full flap robe Willow Figuring out how |
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w****k
发帖数: 6244 | 3 well
for someone, it's helical
for some other, it's a circle
dont trap urself in a circle |
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n******e
发帖数: 623 | 4 2010-11-23至2011-4-27期间所作更新：
经过讨论，经纬台以后都改成经纬仪，符合中国天文名词委习惯。全称"经纬仪式架台装置"或"地平式架台装置"还有日本简称"经纬台"括号注明。
概述部分小改。增加不便携的选择一节。增加电机一段，区分步进电机与伺服电机，使用直流电机手动调速的赤道仪或经纬仪就不收录此总结了（自制门板赤道仪例外）。
国产哈雷HL-1和香港关生TP-1一直是小规模试作，就只在Eyebell CD-1后面备注了。三者外型相似，底座和面板设计略有不同，CD-1使用Vixen的MT-1WT电机，HL-1和TP-1使用国产电机。实测重量（不含微调楔座）分别为：CD-1是1325克，HL-1是1250克，TP-1是1015克。
台湾AstroDesign Star Tracker出了新版ST3CX和ST3CXP。
Vixen线控DD-2升级到DD-3，脚架DP70和HAL130升级到SXG-S71和SXG-HAL130。相应GP2和GP2PG也升级。
加入两个已停产的：Apogee MPFM，MIZAR AR-1（数据不全，放在其他一节），后者一代名机，不少国产赤道仪以之... 阅读全帖 |
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n******e
发帖数: 623 | 5 2010-11-23至2011-4-27期间所作更新：
经过讨论，经纬台以后都改成经纬仪，符合中国天文名词委习惯。全称"经纬仪式架台装置"或"地平式架台装置"还有日本简称"经纬台"括号注明。
概述部分小改。增加不便携的选择一节。增加电机一段，区分步进电机与伺服电机，使用直流电机手动调速的赤道仪或经纬仪就不收录此总结了（自制门板赤道仪例外）。
国产哈雷HL-1和香港关生TP-1一直是小规模试作，就只在Eyebell CD-1后面备注了。三者外型相似，底座和面板设计略有不同，CD-1使用Vixen的MT-1WT电机，HL-1和TP-1使用国产电机。实测重量（不含微调楔座）分别为：CD-1是1325克，HL-1是1250克，TP-1是1015克。
台湾AstroDesign Star Tracker出了新版ST3CX和ST3CXP。
Vixen线控DD-2升级到DD-3，脚架DP70和HAL130升级到SXG-S71和SXG-HAL130。相应GP2和GP2PG也升级。
加入两个已停产的：Apogee MPFM，MIZAR AR-1（数据不全，放在其他一节），后者一代名机，不少国产赤道仪以之... 阅读全帖 |
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s***e
发帖数: 911 | 6 DNA topoisomerases are enzymes that catalyze the passage of individual DNA
strands or double helices through one another. These reactions are often
manifested in interconversions between topological isomers of DNA rings;
hence the name of the enzymes...
There are three enzymes in this group: E.coli DNA topoisomerase I,
mouse DNA topoisomerase I, and E.coli topoisomerase II, respectively,
representing 3 distinct subfamilies of topoisomerases.
Both E.coli DNA topoisomerase I and mouse DNA topoisom |
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d********r
发帖数: 303 | 7 how the channel select the ion? Charge and dimension. yes.
So how about potssium channel?
Look at this figure again.
http://www.hhmi.org/research/investigators/images/mackinnon_fig1_lg.gif
the second pannel of the right figure. The backbone partial negatively charged
carbonyl oxygen atoms actually interact with the postively charged potassium.
Also the partical negative charge from C-term of helices play crucial part.
this is also true for chloride channel, though the geometry of its selective
f |
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v*****n
发帖数: 133 | 8 SNAREs can be grouped into t-SNARE (target) and v-SNARE (vesicle), or Q-SNARE
and R-SNARE based on sequence. 4 families have been found: syntaxin, SNAP-25-1,
SNAP-25-2 (Q type), and synaptobrevin (R type).
SNARE complex during membrane fusion is actually a 4 helical bundle, 2 from each
membrane location in the ratio of 3Q : 1R.
Besides this, the subunit c of the V0 sector of V-type ATPase, also called
proteolipid, is also shown to facilitate homotypic fusion in yeast, which was
published in Nat |
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m**z
发帖数: 787 | 10 NMR没有多少峰的原因很多吧，比如蛋白太大或者多聚,multiple conformational
state等等。。 反正我之前作的一个蛋白，肯定fold是没有问题的（nice alpha-
helical structure by CD and even crystal structure)，NMR出来就是没有几个峰。
我觉得不能用这个来推断没有folding.
相反，没有folding的蛋白据我理解应该有很多峰，只不过这些峰不disperse,全部集中
在HSQC中间的地方，这个好像是没有folding的一个特征。
CD应该是相对容易得看蛋白有没有folding得不错的方法 |
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f*******h
发帖数: 38 | 11 吴号Michael Karin强强联手
搞结构灌水灌的真快
Crystal structure of inhibitor of κB kinase β
Guozhou Xu, Yu-Chih Lo, Qiubai Li, Gennaro Napolitano, Xuefeng Wu, Xuliang Jiang, Michel Dreano,
Michael Karin & Hao Wu
Department of Biochemistry, Weill Cornell Medical College, New York, New York 10021, USA
Guozhou Xu, Yu-Chih Lo, Qiubai Li & Hao Wu
Department of Pharmacology, University of California at San Diego, La Jolla, California 92093, USA
Gennaro Napolitano, Xuefeng Wu & Michael Karin
Nature (2011) doi:1... 阅读全帖 |
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s***m
发帖数: 6197 | 12 Bailor, M.H., Musselman, C., Hansen, A.L., Gulati, K., Patel, D.J. and Al-
Hashimi, H.M. (2007) Characterizing the
relative orientation and dynamics of RNA A-form helices using NMR residual
dipolar couplings. Nat Protoc, 2,
1536-1546.
Please send it to x****[email protected]
Thanks a lot! |
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i******w
发帖数: 407 | 13 引用数量有毛用啊？忍不住说两句了
物理里面引用上万次的多了去了： 比如Iijima 的 Helical microtubules of
graphitic carbon，被引了23125次，还不是没拿炸药奖，重要性也就一般般了，现在
top 10的物理系早没人做碳管了。
汤超那篇引用5000次的Self-organized criticality的文章完全是丹麦50年来最伟大物
理学家Per Bak的工作，说白了就是Per Bak的一篇blog，写了点自己的idea。
汤超和Kurt Wiesenfeld这两个postdoc也就是给Per Bak跑腿的而已
Self-organized criticality在90年代红极一时，后来大家发现也没什么实际应用，理
论上也很清楚了，现在已经没有人再研究了。
看看人家sunney xie 的工作，重要性每年都在指数增长，拿炸药奖是迟早的事情，我
觉得很可能和Moerner一起拿。 |
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s******9
发帖数: 283 | 14 E. coli ToA domain II, a very long alpha-helical domain and you can excise
any length of fragments from it for your purpose. It serves as a spacer
region for ribosome display. |
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k*****1
发帖数: 454 | 15 哈哈，刚刚很无聊的google了一下，DNA在电场中还真是rotate了，而机理大致和我推
测的是一样的，就是因为电荷的分布不均匀。
【The mechanism of ion polarisation along DNA double helices】
Dietmar Porschke，Biophysical Chemistry， 1985.
感叹一句，科学家还真是无聊，这种实验也想到做了...... |
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s***e
发帖数: 911 | 16 如果YAP1是链接在alpha-catenin上，那应该受力调控吧。alpha-catenin有actin
binding domain. 几个皮牛就能把alpha-catenin的alpha-helice bundle解开。比如5
个皮牛的力就能把vinculin结合到alpha-catenin的affinity 增加100-1000倍。而5 pN
也就是一两个myosin能产生的力。 |
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h*******b
发帖数: 275 | 17 http://onlinelibrary.wiley.com/doi/10.1002/psc.2722/full
Prokaryotic expression and antimicrobial mechanism of XPF-St7-derived α-
helical peptides
[email protected]
(function(){try{var s,a,i,j,r,c,l,b=document.getElementsByTagName("script");l=b[b.length-1].previousSibling;a=l.getAttribute('data-cfemail');if(a){s='';r=parseInt(a.substr(0,2),16);for(j=2;a.length-j;j+=2){c=parseInt(a.substr(j,2),16)^r;s+=String.fromCharCode(c);}s=document.createTextNode(s);l.parentNode.replaceChild(s,l);}}catch(e){... 阅读全帖 |
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l********7
发帖数: 110 | 19 Enhanced Photocurrent Generation by Electron Hopping through Regularly-
Arranged Chromophores in a Helical Peptide Monolayer
Tomoyuki Morita, Kazuyuki Yanagisawa and Shunsaku Kimura
Polymer Journal, 2008, 40, 700-709
My email is l*****[email protected].
Thanks. |
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c*****t
发帖数: 198 | 20 Thanks a lot for sending the paper. However, it is another paper. Could
you please send me the paper
Lessons from Viruses: Controlling the Function of Transmembrane Proteins
by Interfering Transmembrane Helices
Authors: Cymer, F.1; Schneider, D.1
Source: Current Medicinal Chemistry, Volume 15, Number 8, April 2008 , pp.
779-785(7)
Publisher: Bentham Science Publishers
It is in the same journal of the paper in the link you sent me. |
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J****t
发帖数: 60 | 21 因没有权限下载不了，只好来这里求助大家。以下3篇，多谢了！
An Iterative Synthesis of π-Conjugated Oligomers
Y Nakao, J Chen, M Tanaka, T Hiyama
Synfacts 2007 (12), 1265-1265
https://www.thieme-connect.com/ejournals/abstract/10.1055/s-2007-991356
Synthesis of Chiral Allylsilanes by Enantioselective Conjugate Addition
R Shintani, Y Ichikawa, T Hayashi, J Chen, Y Nakao, T Hiyama
Synfacts 2008 (1), 0054-0054
https://www.thieme-connect.com/ejournals/abstract/10.1055/s-2007-991486
A Novel Hydrogen-Bonding Catalyst Class with Heli... 阅读全帖 |
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l********e
发帖数: 214 | 23 【 以下文字转载自 Postdoc 讨论区 】
发信人: LongTongue (longlong), 信区: Postdoc
标 题: Full text paper needed
发信站: BBS 未名空间站 (Tue Dec 16 13:57:09 2008)
A finite element for dynamic analysis of a cylindrical isotropic helical
spring
JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES
Vol. 3 (2008), No. 4, 641-658
To: j***[email protected]
Thanks |
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c*s
发帖数: 2145 | 24 in the latest Angewandte Chemie International Edition pp 1705-
using Supramolecular Ribbons as Templated to prepare Semiconductor Nanohelices
there are two interesting points:
1. to what extent can we control the shape of inorgaqnic materials through a
template? we know that organic molecules are soft thus seems plausible that
we can't get inorganic solid with special shape by this soft template...
But from this result, we can see that the nano CdS helices has fairly well
-defined structure |
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c*s
发帖数: 2145 | 25 maybe inaddition,
the nature of the interaction between the template and final product is also
intersting...
is that Vander Walls force? complexing bong between metal ions and O atom( not
plausible cuz teh media of reaction is THF)
but it seems there existes special interaction, based on the fact thta there
is no isolated CdS PARTICLES isolated from the template..
Nanohelices
that
HELICE |
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w********h
发帖数: 12367 | 26 Helical superstructure from an achiral banana-shaped liquid crystal
Lee CK, Chien LC
FERROELECTRICS
243 (1-4): 231-+ 2000
but |
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s*****n
发帖数: 741 | 27 最近在想做一个具有helix性质的polymer， 但是不想用侧链的位阻来产生helix。
我所知道的有些PU是可以的，除了这些之外，还有其它办法不？
请问有没有专门的书籍全面的介绍helix polymer 的？
欢迎大家指导！ |
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j*********5
发帖数: 6221 | 28 用Hbond可以吗，像多肽性质的，或者pai-pai staking，像DNA，其实helix 结构形成
无非就这些weak interaction或者空间位阻吧，
俺不是polymer的外行，随便扯点 |
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w********h
发帖数: 12367 | 29 Italian physics professor Enzo Di Fabrizio captures twisted ladder that
props up life
DNA's double-helix structure is on display for the first time in this
electron microscope photograph of a small bundle of DNA strands.
Fifty-nine years after James Watson and Francis Crick deduced the double-
helix structure of DNA, a scientist has captured the first direct photograph
of the twisted ladder that props up life.
Enzo Di Fabrizio, a physics professor at Magna Graecia University in
Catanzaro, Italy,... 阅读全帖 |
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D***e
发帖数: 48486 | 30 在一个论坛查到了
用的是datum curves
当然也可以切, Helical Sweep |
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发帖数: 1 | 32 方向：
Helical Dielectric Elastomer Actuator (HDEA)
Artificial Muscle
ElectroActive Polymers (EAP)
FEA
邮箱（长期有效）：
[email protected] |
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T****t
发帖数: 616 | 33 which of the following is most likely associated with the requirement of
developing a live attenuated vaccine?
DNA virus
RNA virus
enveloped virus
naked virus
helical virus
icosahedral virus
syncytial virus |
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c****e
发帖数: 2097 | 34
you mean helicity stuff, like the spinors of some other signature? you
working on twistors? |
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T*********r
发帖数: 11175 | 35 J和psi都是通过衰变到e+ e-找到的
spin0的粒子如果decay到e+ e-的话，是要flip helicity的
最后总是和electron mass成正比的
但是electron mass那么小，所以这个可以忽略了
但是spin1 decay到e+ e-就没这问题，有了eletron pair就比较容易找 |
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w******a
发帖数: 2592 | 36 go to helicity basis...
for example, check MHV amplitude |
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S***p
发帖数: 19902 | 37 helicity 只是质量为０粒子的本征态吧？那不还是极限质量近似 |
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Q******g
发帖数: 607 | 38 只要知道是Lorentz群的表示就够了。这个世界是按Lorentz群变换的，
所以粒子们也随着表示变换。因此就有了自旋0、1/2、1等等的粒子。
如果只有整数没有半整数，那才奇怪。
你那个自旋为1的解释似是而非。为什么重力子的自旋为2呢？规范对称
并不是真的（物理的）对称性，只不过是我们数学描述上的多余自由度
罢了。规范变换不是不同物理态之间的变换，而是相同物理态不同数学
描述之间的变换。我们还没有更好的数学描述不引进多余自由度。
其实对于质量为0的Lorentz群的表示与有质量的情况很不相同。严格说
不是自旋而是旋量（helicity）。建议看一下Weinberg的书关于小群的
部分。 |
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t********y
发帖数: 166 | 39 In 1953, James Watson and Francis Crick suggested what is now accepted as
the first correct double-helix model of DNA structure in the journal Nature.
[5] Their double-helix, molecular model of DNA was then based on a single X-
ray diffraction image (labeled as "Photo 51")[169] taken by Rosalind
Franklin and Raymond Gosling in May 1952, as well as the information that
the DNA bases are paired — also obtained through private communications
from Erwin Chargaff in the previous years. Chargaff's rul... 阅读全帖 |
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p*******s
发帖数: 91 | 41 you want to how much to build one system? or be treated by it?
it costs a few million dollars to buy one system |
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n***a
发帖数: 1373 | 42 Just checked up to date.
"Noncontrast helical CT scan is the gold standard for the radiologic
diagnosis of renal stone disease (image 5A-B), including the detection of
small stones or ureteral stones not detectable by ultrasound or stones not
visualized on plain films of the abdomen, and is the appropriate initial
imaging test for suspected renal colic" |
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I***i
发帖数: 14557 | 43 http://news.sciencemag.org/sciencenow/2012/06/mantis-shrimp-sma
Mantis Shrimp Smash!
by Gisela Telis on 7 June 2012, 2:24 PM
The peacock mantis shrimp packs a powerful punch. The crustacean uses its
hammerlike claws to smash through mollusk shells and even aquarium glass
without getting injured. Now, a new study reveals what makes its claws so
tough: a unique composition and structure that stops cracks in their tracks
—one that could help engineers design lighter, stronger materials for
military... 阅读全帖 |
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b**s
发帖数: 4571 | 44 helical fletching, 主要是hunting用，增加旋转和稳定性。
straight fletching，主要是打靶用。 |
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o******s
发帖数: 1364 | 45 I use bhoening. The straight is fine. The helical is simply an offset and
doesn't meet my desired angle.
jig |
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o******s
发帖数: 1364 | 46 Your helical fletch looks like just offset a few degrees (like the result
from my Bohening). Do you have comments on its use with broadhead? |
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g**e
发帖数: 6127 | 47 我的到400rwhp要多少钱？
Fidanza flywheel,TRD helical LSD,Koni yellow shocks,Ground Control coilover,
Magnaflow exhaust,Injen short ram intake,Beatrush Aluminum underpanel,
painted rims |
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p*********e
发帖数: 32207 | 48 问题在于,用worm gear或者helical gear的LSD
你可以在限滑的同时抑制驱动轮的反向作用
而clutch type的,你如果要抑制驱动轮的反作用就要取消LSD而变成开式差速器
些。
understeering |
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t*a
发帖数: 18880 | 49 只是觉得在altima上有点可惜。
哪怕是个celica,老prelude也好。
flywheel,TRD helical LSD,Koni yellow shocks,Ground Control coilover,
Magnaflow exhaust,Injen short ram intake,C-one Aluminum underpanel,painted
rims,Moroso aluminum baffled oil pan,port: |
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c*********r
发帖数: 19468 | 50 不是的，RSX是第四代Integra (DC5)，没有出过Type-R版
美国这边一般说的Type-R，都是指第三代Integra (DC2)
它有Type-R版，而且来过美国，并且在SCCA的TC赛里统治过多年
一般来说，Integra这么小的FWD前悬挂肯定是MacPherson，DC5也不例外
但是DC2的时候还是双叉臂的，加上车头轻，整个车重也轻
又是最早在前轴采用helical-gear LSD的车型之一
配合升功率过百的高转NA引擎B18C (以那个年代的I4来说，其实它的升扭矩也很高)
DC2 Type-R自然是很受推崇的，公认的有史以来操控最好的FWD之一啦
（有人会argue是否要去掉“之一”这两个字吧？） |
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