fe 发帖数: 286 | 1 PMF is for protein identification. But if you have a matched protein with
a good score, then you'll know the identity of the peptides, right? |
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G***G 发帖数: 16778 | 3 您的最后一句是什么意思?最后一句中的MS technology是指的MS/MS?
serum属于complex sample吗?
PMF |
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b*******g 发帖数: 1309 | 4 protein digestion 3 个小时完成不了
复杂一点的proteomics 实验都要一两天吧。。。
有个建议,你们这个仪器能做TOF/TOF吧,
比较一下proteomics ID 用 PMF 跟 MS/MS search database的区别
一人两个蛋白,一个已知,一个未知,第三个 两个蛋白混在一起
已知的看准确度,未知的看ID 对不对
TRYPSIN |
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y***l 发帖数: 1095 | 5 谢谢,我这个外行还需要继续科普。。。请问PMF是什么?
我们是可以作TOF/TOF的,就是用LIFT对吗?
还有,有什么推荐的蛋白吗?
蛋白还是需要学生先DIGEST吗?
如果想找具体的实验步骤,有没有推荐的书或PAPER可以参考?谢谢!!
非常感谢! |
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f*********e 发帖数: 1144 | 6 The software together with Autoflex (FlexAnalysis/Biotools) are not that
easy themselves, you don't want to get yourself trapped if you are not
familiar with them.
Skip MS2, just fire on a couple spots and show them the peaks. Make it like
a PC game. Peptides PMF is enough together with calibration (well,
calibration is kinda tricky too). Don't try intact proteins.
We had 3 days onsite training on Autoflex w/o LIFT and I still keep bugging
bruker.....shame on me...hehehehehe |
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f*********e 发帖数: 1144 | 7 If u did pmf, what's the sequence coverage? Compare the one without vc and
the one with vc, if u really want to figure out the peak, do a differential
mapping. Use maldi for digest mapping would be much easier。
And what column are u using?
weight |
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b****r 发帖数: 2555 | 8 There is no such thing as P-polarizer-sheet or S-polarizer-sheet, but
you can use a PBS (polarization beam splitter), which can tell you
-roughly- if the light is p-polarized or s-polarized.
But still, there are many technical difficulties in your experimental
setup:
1. what fiber you are using? PMF (polarization-maintain fiber) can
give you a linear polarized output, but the polarization orientation
is dependent on your fiber orientation. Rotate your fiber output end
and you will get a differen |
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m****t 发帖数: 2684 | 9 PMF有太大的不确定性,EPA也说这个只表明相对重要性,而不是绝对的,而且他的那副
source profile图(8)的问题太大,应该要进一步细分,否则很难看出这些源有什么
区别,把其中一个因子叫‘Traffic and waste incineration emission’,就说明他
基本不知道这个东西是什么。
另外CMB结果里的‘unidentified’的成分相当大,这个结果也就是发发文章,离实际
情况远了去了。 |
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s*********y 发帖数: 2653 | 10 同意,其实PMF是个很扯的东西,使用者要有对分析对象良好的认识,因为你输入的
factor的数量都是自己设定的,run出来的结果不好的话还要重新调试输入参数,再run
,直到能自圆其说为止。。。 |
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h****r 发帖数: 9 | 11 A dice is tossed K times (K is a constant): P(X_k = i)=p_i, i=1~6 (when even
, p_i=1/6). The outcomes are summed up. Y=\sum_{k}X_k. What's the pmf of Y?
Is this a trival problem? |
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z*******e 发帖数: 777 | 12 大家好,
近来要用统计的知识,这方面我知道的太少,有个问题请指点一二,谢谢。
如果Service time 是3秒(也就是随机变量S(t)为常数),S的分布函数F(t)或者密度分布函数pmf是什么呢? |
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a**e 发帖数: 5794 | 13 我猜你想说average service time是3秒,那么waiting time的分布是
exponential
度分布函数pmf是什么呢? |
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z*******e 发帖数: 777 | 14 大家好,
近来要用统计的知识,这方面我知道的太少,有个问题请指点一二,谢谢。
如果Service time 是3秒(也就是随机变量S(t)为常数),S的分布函数F(t)或者密度分布函数pmf是什么呢? |
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s*****n 发帖数: 2174 | 15 什么叫service time? 你是想问一个单点(分布)的PMF或者CDF是什么吗? |
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D*****a 发帖数: 2847 | 16 什么乱七八糟的
常数还随机个啥
度分布函数pmf是什么呢? |
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s*****n 发帖数: 2174 | 17 单点分布
PMF: P(ST = 3) = 1
CDF:
F(t) = P(ST <= t) = 0 if t < 3,
F(t) = P(ST <= t) = 1 if t >= 3. |
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s*****n 发帖数: 2174 | 18 histogram 本身就是一种exploratory methods, 没什么量化的概念.
你所说的peak高低, 数量, 那些不是用来描述histogram的, 而是用来描述其背后所代
表的pdf(或离散情况下的pmf). |
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m****r 发帖数: 237 | 19 P(Z=z)=exp(-mu)*mu^(z/2)/((z/2)!)
This is the pmf for Z=2*x1 |
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D******n 发帖数: 2836 | 20 create a .vim directory under you home directory(there is a dot before
vim)
and then create a syntax directory under it
and then create a sas.vim file under the syntax directory
==============sas.vim======================
if version < 600
syntax clear
elseif exists("b:current_syntax")
finish
endif
syn case ignore
syn region sasString start=+"+ skip=+\\|\"+ end=+"+
syn region sasString start=+'+ skip=+\\|\"+ end=+'+
" Want region from 'cards;' to ';' to be captured (Bob Heckel)
sy... 阅读全帖 |
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k*******a 发帖数: 772 | 21 E(xi*xj)-E(xi)E(xj)
E(xi)=npi
E(xj)=npj
E(xi*xj)的话你可以得到 n(n-1)pipj, 这个你可以直接用 pmf*xixj 然后对所有x1...
xn求和得到expected value |
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y*****w 发帖数: 1350 | 22 Actually the intercept in the ODS output is the estimated log mean of the
fitted gamma distribution, so I don't need the output statement in PROC
GENMOD. The pertinent code becomes:
proc genmod data=mydata;
model visit = / dist=gamma link=log;
freq episode;
ods output parameterestimates=pe;
run;
proc transpose data=pe out=tpe;
var estimate;
id parameter;
run;
data _null_;
set tpe;
call symputx("logmean", intercept);
call symputx("scale", scale);
stop;
run;
data pmf;
do t = 1 ... 阅读全帖 |
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P*****r 发帖数: 554 | 23 6似乎是对的,但是这个求解方法好像不太好interpret啊,呵呵
一般要先找PMF,再算mean的 |
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P*****r 发帖数: 554 | 24 哪敢称大侠,lol
常规解法就是定义下variable,算下pmf,找出mgf,然后就得到mean了
不过貌似很耗时间哈,跟这种解法比起来简直被甩掉了十几条街 |
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p***l 发帖数: 134 | 25 Use a conditional-unconditional formula, the idea is crystal clear and easy.
It is a classic technique for martingale/stochastic process problem.
Let X=# of tosses until you observe two heads in a row, Y1=the result of the
first toss. Also denote x=E(X) for consistency with your equation.
x=E(X)=E[E(X|Y1)]= E(X|Y1=T)/2 + E(X|Y1=H)/2
Note that Y1 is independent of the remaining tosses. Provided Y1=T, the "
head counter" is reset. Hence E(X|Y1=T)=E(1+X)=1+x. Provided Y1=H, you have
.5:.5 condition... 阅读全帖 |
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h***i 发帖数: 3844 | 26 6 points is good for pmf not pdf |
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z****u 发帖数: 1007 | 27 如果治疗前发现是overtreatment,那是没法去告医生的,因为还没有任何治疗发生。如
果治疗之后有确切证据证实overtreatment,那还有些机会。
一般是先由医生制定方案,和病人讨论,同意了,送去保险公司审批,审批下来了才开
始治疗。保险公司判断方案合理与否的标准基本就是XRay,以及insurance plan
coverage 项目。 所以我觉得像你们,应该确定什么是你们最需要的治疗,先进行,别
的再说。
这里普通的PMF也是Ni-Ti合金。full ceramics当然有了,价钱会比普通PFM贵不少呢。
如果是后牙那就用不着了啊。 |
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z****u 发帖数: 1007 | 28 如果治疗前发现是overtreatment,那是没法去告医生的,因为还没有任何治疗发生。如
果治疗之后有确切证据证实overtreatment,那还有些机会。
一般是先由医生制定方案,和病人讨论,同意了,送去保险公司审批,审批下来了才开
始治疗。保险公司判断方案合理与否的标准基本就是XRay,以及insurance plan
coverage 项目。 所以我觉得像你们,应该确定什么是你们最需要的治疗,先进行,别
的再说。
这里普通的PMF也是Ni-Ti合金。full ceramics当然有了,价钱会比普通PFM贵不少呢。
如果是后牙那就用不着了啊。 |
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