Monday, October 12, 2009
Next Generation Genome Browser
When David, Fang Fang and I talk about UCSC Genome Browser today, I said "I would like a genome browser like Google Map". Later I find I become more excited about this idea: the next generation genome browser, which provides an more user friendly and powerful platform to ornanize and display genomic information.
What does the next genome browser ("genome map") look like ?
First, smoother zoom in and zoom out. Genomes are organized in hierarchical structure. Sometimes we need a birdview of the whole genome and sometimes we are interested in subtle local structures. It is of great value if we are change the resolution when examining the genome. So, we need dynamic and smoother zoom in and zoom out just like the little sliding bar in Google map. (update: I came across Jbrowser and Anno J browser that seems to have this function. See reference)
Second, advanced searching functions. Current genome browser are only able to search by genomic location, as a result the vast amount of annotation information can not be searched in genome browser. It will be cool there is a search box. Users input a keyword , such as a gene name and the our genome map display those regions match the query.
Third, what kind of web technology should we need? Ajax? Database back end? XML? Maybe google map is a good starting point.
There seems great possibility that such a genome map will appear and what other features are you looking for in the next generation genome brower?
Ref:
1. Skinner ME, Uzilov AV, Stein LD, Mungall CJ, Holmes IH. JBrowse: A next-generation genome browser. Genome Res. (2009) http://jbrowse.org/
2. AnnoJ Browser http://www.annoj.org/index.shtml
Friday, March 06, 2009
Exon/Intron Statistics in Human Genome
| Table 1: | Exon - intron distributions for human genome |
| Chr # | Total # genes | Total # exons | Total # introns | Max # exons/gene | Chromosome size (determined) | Avg # of exons/gene | Avg length (bp) | Std dev. | Total length (bp) | Shortest (bp) | Longest (bp) | |||||||
| exon | intron | exon | intron | exon | intron | exon | intron | gene | exon | intron | gene | |||||||
| 1 | 2514 | 22345 | 19831 | 107 | 226828929 | 8.89 | 167.01 | 4736.52 | 229.37 | 14268.19 | 3731870 | 93929919 | 2 | 1 | 78 | 8449 | 476158 | 980961 |
| 2 | 1354 | 12506 | 11152 | 148 | 238349289 | 9.24 | 163.98 | 5883.23 | 226.88 | 17012.24 | 2050855 | 65609873 | 2 | 1 | 90 | 7572 | 483412 | 1897544 |
| 3 | 1394 | 13517 | 12123 | 118 | 195073306 | 9.70 | 164.06 | 6375.63 | 224.21 | 21019.22 | 2217700 | 77291760 | 2 | 1 | 150 | 6654 | 497816 | 990999 |
| 4 | 926 | 8299 | 7373 | 85 | 187239983 | 8.96 | 174.78 | 7168.94 | 266.64 | 19497.08 | 1450541 | 52856617 | 2 | 53 | 132 | 6255 | 494708 | 1467842 |
| 5 | 1186 | 9946 | 8760 | 90 | 177696509 | 8.39 | 189.50 | 7277.28 | 332.86 | 21277.20 | 1884777 | 63748970 | 2 | 1 | 150 | 6574 | 370360 | 930401 |
| 6 | 1306 | 11406 | 10100 | 145 | 169212327 | 8.73 | 173.62 | 5961.61 | 253.56 | 18967.75 | 1980397 | 60212251 | 2 | 31 | 159 | 7152 | 469892 | 1377570 |
| 7 | 2508 | 23045 | 20537 | 82 | 310210944 | 9.19 | 167.87 | 6703.87 | 271.88 | 20177.41 | 3868769 | 137677396 | 2 | 1 | 14 | 11923 | 458139 | 1641567 |
| 8 | 908 | 7823 | 6915 | 86 | 143297300 | 8.62 | 171.16 | 7354.15 | 258.43 | 21384.09 | 1339052 | 50853964 | 2 | 54 | 84 | 7308 | 453268 | 2055833 |
| 9 | 1033 | 8941 | 7908 | 72 | 117790386 | 8.66 | 170.66 | 5351.68 | 253.19 | 14121.26 | 1525926 | 42321074 | 2 | 33 | 105 | 6598 | 276306 | 865661 |
| 10 | 1017 | 10273 | 9256 | 69 | 132016990 | 10.10 | 153.79 | 6412.91 | 219.97 | 20271.48 | 1579898 | 59357955 | 2 | 52 | 105 | 7812 | 482575 | 1727184 |
| 11 | 1567 | 12459 | 10892 | 87 | 130908954 | 7.95 | 177.66 | 4341.42 | 237.03 | 15362.46 | 2213526 | 47286795 | 3 | 1 | 87 | 6183 | 437543 | 1463302 |
| 12 | 1299 | 12399 | 11100 | 89 | 129826379 | 9.55 | 158.07 | 4570.21 | 192.23 | 12979.23 | 1959945 | 50729293 | 2 | 30 | 81 | 6324 | 328545 | 1248678 |
| 13 | 426 | 3784 | 3358 | 83 | 95749578 | 8.88 | 183.47 | 7351.75 | 396.79 | 19082.4 | 694268 | 24687182 | 2 | 37 | 279 | 11555 | 317646 | 1175762 |
| 14 | 854 | 6837 | 6106 | 114 | 87191216 | 8.01 | 176.24 | 5653.70 | 276.66 | 19076.38 | 1204982 | 33826109 | 2 | 51 | 51 | 11304 | 479079 | 1210740 |
| 15 | 843 | 8106 | 7263 | 104 | 81992482 | 9.62 | 169.79 | 4660.70 | 271.38 | 11542.05 | 1376321 | 33850721 | 2 | 1 | 168 | 9527 | 207178 | 620362 |
| 16 | 1093 | 9986 | 8893 | 62 | 79932432 | 9.14 | 166.96 | 3661.25 | 242.60 | 13092.99 | 1667340 | 32559472 | 2 | 1 | 75 | 8607 | 466049 | 1167938 |
| 17 | 1459 | 13179 | 11720 | 74 | 79376966 | 9.03 | 165.08 | 3193.16 | 215.89 | 9875.72 | 2175698 | 37423835 | 2 | 30 | 63 | 4786 | 283762 | 712668 |
| 18 | 367 | 3333 | 2966 | 75 | 74658403 | 9.08 | 174.9 | 7905.40 | 256.53 | 19377.24 | 583054 | 23447419 | 3 | 67 | 225 | 4721 | 411175 | 1189866 |
| 19 | 1609 | 12169 | 10560 | 106 | 55878340 | 7.56 | 187.31 | 2032.87 | 279.92 | 4741.54 | 2279436 | 21467122 | 2 | 1 | 81 | 5059 | 170796 | 298909 |
| 20 | 775 | 6492 | 5717 | 80 | 59424990 | 8.38 | 160.34 | 4403.10 | 215.29 | 13613.39 | 1040952 | 25172558 | 3 | 54 | 135 | 3738 | 303713 | 1108855 |
| 21 | 309 | 2539 | 2230 | 47 | 33924367 | 8.22 | 168.59 | 5086.89 | 306.51 | 16098.67 | 428056 | 11343761 | 3 | 74 | 102 | 5916 | 323563 | 833627 |
| 22 | 671 | 5173 | 4502 | 54 | 34352072 | 7.71 | 171.14 | 3924.83 | 281.85 | 12999.39 | 885356 | 17669584 | 3 | 42 | 38 | 6762 | 447252 | 492969 |
| X | 1048 | 8568 | 7520 | 79 | 152118949 | 8.18 | 185.33 | 7627.85 | 299.66 | 23527.35 | 1587926 | 57361443 | 2 | 54 | 129 | 6102 | 493512 | 2217347 |
| Y | 98 | 660 | 562 | 44 | 24649555 | 6.73 | 173.74 | 5288.54 | 255.05 | 19676.46 | 114670 | 2972162 | 3 | 67 | 228 | 2493 | 400349 | 681119 |
Wednesday, February 18, 2009
Emacs Note
http://xtalk.msk.su/~ott/common/emacs/rc/emacs-rc-cedet.el.html
http://cedet.sourceforge.net/
http://cscope.sourceforge.net/
http://ecb.sourceforge.net/
2. How can I use emacs without gui when I work on a remote machine with a slow connection?
emacs -nw
3. In emacs shell mode, what setting need I modify to make the shell promote PS1 display correctly, e.g. with color like in a terminal?
Add the following code in your .emacs
(autoload 'ansi-color-for-comint-mode-on "ansi-color" nil t)
(add-hook 'shell-mode-hook 'ansi-color-for-comint-mode-on)
4. After I update to emacs 23, invoking flyspell-mode gives the following error "Enabling flyspell-mode gave an error".
This is caused by the conflicts between site dictionaries and the dictionaries in emacs 23.It can be fixed as following:
cd /usr/share/emacs23/site-lisp/dictionaries-common5. How do I enable double spaces in emacs?
sudo rm *.el *.elc
This feature is provided in the package setspace. Add the following commands in the preamble of your tex file.
\usepackage{setspace}6. Which font looks pretty in emacs?
\doublespacing
My personal favourite is Nimbus Mono L regular.
7. In org-mode, how can I change the default browser?
Add the following two lines in your .emacs file:
(setq browse-url-browser-function (quote browse-url-generic))Similarly, if you want to use the open sourced version of Chrome Browser instead of the Google rebranded version, replace "google-chrome" with "chromium-browser"; if you want to use firefox, replace "google-chrome" with "firefox".
(setq browse-url-generic-program "google-chrome")
8. I copy some text in emacs, how can I paste the text another application?
In your .emacs file. add the follow line
(setq x-select-enable-clipboard t)
Monday, February 16, 2009
Latex Notes
Tips:
1. How to type mathematical symbols2. How to display the text under an max or sup operator?
3. Use the following packages to make your docs more pretty
\usepackage{times, fullpage}
4. How can I input the addition assign (+=) operator in latex?
\mathrel{\mathop+}=
5. How can I move all figures and tables to the end of article?
Use the package endfloat http://www.ctan.org/pkg/endfloat
6. How can I edit and generate files in Chinese?
Use the xelatex command, see a simple template at https://github.com/songqiang/latex-templates/blob/master/latex-template-xelatex.tex
Good read:
- 陈硕: 用 LaTeX 排版技术书籍 https://github.com/chenshuo/typeset
- 无有的笔记空间: LaTeX 排版学习笔记 http://zoho.is-programmer.com/posts/30662.html
Thursday, December 04, 2008
Installing Ubuntu on HP Pavilion dv 4 1114nr
1. Create Windows Vista recovery disk
Boot into Window s Vista. First, since HP does not provide recovery disk with new laptops any longer, you need to create your own recovery disks in case you need Windows Vista in the future. Start -> Recovery Disk Creation and follow the instructions.
2. Re-participation the hard drive
Windows Vista comes with hand drive resizing and re-participation utilities. That's cool! It saves our trouble to search for a 3rd party software.
Follow the instructions in the following documents:
1. Screenshot Tour: Repartition your hard drive in Windows Vista
2. Can I repartition my hard disk?
3. Download
Don't bother to download ubuntu installation iso and create your own installation CD. If you have internet access (a fair weak condition, isn't it?), you can use Unetbootin (http://en.wikipedia.org/wiki/UNetbootin).
I am not exactly sure. There seems a bug with Unetbootin.
I participated my hard drive into three particitions: C: windows system partition; D: HP recovery partition; F: unformated free partition, which is intended for Linux installation.
But when I select mode as Hard Drive, only C: partition is displayed; I have to select USB Live mode and select F: partition there. I am not sure what this implies, still waiting for the result.
5. sound issues
After the installation, the speaker and the microphone does not work. Particularly, I could not use skype :-(.
Solution to "no sound problem"
Open
sudo vi /etc/modprobe.d/alsa-base
Add the following line to the end of the file
options options snd-hda-intel model=laptop enable_msi=1
Solution to microphone problem:
It is possible due to the mic is muted.
Open Volume Control by double clicking the icon at top-right corner. Select preference and select the device for recording and playback. And cancel the mutation option.
Solution to skype "Audio playback" problem
Excute the following command in a terminal
killall pulseaudiorefer to http://www.econowics.com/news-from-the-net/170/skype-problem-with-audio-playback-ubuntu-810-intrepid-ibex/
sudo apt-get remove pulseaudio # this seems not necessary
sudo apt-get install esound
sudo rm /etc/X11/Xsession.d/70pulseaudio
refer to
https://bugs.launchpad.net/ubuntu/+bug/269586
https://help.ubuntu.com/community/HdaIntelSoundHowto
6. install skype
7. install songbird
8. install Java Runtime Environment
9. install Open Office 3.0
10. install Mac4lin
11. install VLC and other codecs
12 install sopcast and gsopcast (online TV channel)
13 install fcitx Chinese input
First remove default scim framework and install fcitx
next modify Xsession to automatically start fictx for all users. Opensudo apt-get autoremove scim
sudo apt-get install fcitx
sudo gedit /etc/X11/Xsession.d/95xinputand chang it to
export XMODIFIERS=@im=fcitxOpen
export XIM=fcitx
export XIM_PROGRAM=fcitx
export GTK_IM_MODULE=fcitx
export QT_IM_MODULE=XIM
fcitx
Change the line about xim tosudo vim /usr/lib/gtk-2.0/2.10.0/immodule-files.d/libgtk2.0-0.immodules
"xim" "X Input Method" "gtk20" "/usr/share/locale" "en:ko:ja:th:zh"======
Well, I come back to update this post. I just returned this hp laptop. This was the first time I bought a laptop from HP, unfortunately it was an disappointing experience. I have two issues to complain. The cpu fan is too noise. Even after I disabled the feature "Keep fan running" in BIOS, the fan still makes too much noise. The CD -ROM drive is not quiet either; it feels earthquake when the CD drive is working.
The recovery too is also annoying. I could not recovery my laptop to factory configuration, either via harddrive recovery tool or via recovery CDs. It failed with the "error 1002"; and the HP customer service can not provide any useful help (they outsource custume serive to India, as a result we have to adapt to Indian English).
Anyway, I will blacklist this model from HP: HP Pavilion dv4.
Reference:
1. Screenshot Tour: Repartition your hard drive in Windows Vista
2. Can I repartition my hard disk?
3. Unetbootin http://unetbootin.sourceforge.net/
4. Tutorial: Ubuntu Linux on HP Pavilion
http://aldeby.org/blog/index.php/howto-ubuntu-linux-on-hp-pavilion-dv2000-dv6000-dv9000-series-laptops
5. http://www.dailygyan.com/2008/11/10-things-you-should-do-immediately.html
6. Top 10 Ubuntu downloads http://lifehacker.com/5227309/top-10-ubuntu-downloads
7. http://theindexer.wordpress.com/2009/04/24/to-do-list-after-installing-ubuntu-904-aka-jaunty-jackalope/
8. Install Microsoft YaHei font http://hi.baidu.com/zzy011/blog/item/6651e3ed44a9c62f63d09f37.html
Saturday, November 08, 2008
<R>andom Notes
1. how to estimate the running time of a R function?
R has a function proc.time() http://rweb.stat.umn.edu/R/library/base/html/proc.time.htmlsample code
## a way to time an R expression: system.time is preferred > ptm <- proc.time() > for (i in 1:50) mad(stats::runif(500)) > proc.time() - ptm user system elapsed 0.039 0.001 0.052 ## End(Not run)
2. string manipulation in R
define a string> s = "some characters"
convert other type into a string
> s = as.character(some_variable_in_other_type)
Convert a string into numbers
> pi = as.numeric("3.14159")
string length
>nchar(s)
string concatenation
> s1 = "string1"
> s2 = "string2"
> paste(s1, s2, sep = "")
given a vector of strings, vs, return a string that is the concatenation of vs's elements
> vs = c("song", "qiang")
> paste(vs, collapse = "")
"song qiang"
string splicing
suppose s is a string, how do we slice a substring of the s given starting position and ending position?
we use the following function. there is no default value for stop. it the value of stop is larger the the total
length of string, it is truncated to the length of the string
> substr(s, first = 1, stop = 12)
string split
> strsplit("song qiang", split=" ")
[1] "song" "qiang"
3. when making figures with legend box, the text expand out of legend box when we use dev.copy2eps() to convert the figure image to a eps file
This problem comes from the different specification of font sizes in difference devices. A ugly way to solve this problem is to specify text.width=strwidth("some string"),where "some string" refers to the longest legend text plus some extra characters. The optimal number of extra characters should be determined by trial and error.
4. How to handle exceptions in R?
Read about two functions try and tryCatch (R FAQ 7.32). An example with try is shown below:
for(i in 1:16)
{
result <- try(nonlinear_modeling(i));
if(class(result) == "try-error") next;
}
GNU/Linux Notes
1. How to speed up my Linux booting?
See Bootchart http://www.bootchart.org/index.html
and remove unnecessary services in the booting process
2. One important thing to remember when creating a SVN repository
In Subversion 1.1, a repository is created with a Berkeley
DB back-end by default. This behavior may change in future
releases. Regardless, the type can be explicitly chosen with
the --fs-type argument:
$ svnadmin create --fs-type fsfs /path/to/repos $ svnadmin create --fs-type bdb /path/to/other/repos
Do not create a Berkeley DB repository on a network
share—it cannot exist on a remote
filesystem such as NFS, AFS, or Windows SMB. Berkeley DB
requires that the underlying filesystem implement strict POSIX
locking semantics, and more importantly, the ability to map
files directly into process memory. Almost no network
filesystems provide these features. If you attempt to use
Berkeley DB on a network share, the results are
unpredictable—you may see mysterious errors right away,
or it may be months before you discover that your repository
database is subtly corrupted.
If you need multiple computers to access the repository,
you create an FSFS repository on the network share, not a
Berkeley DB repository. Or better yet, set up a real server
process (such as Apache or svnserve), store
the repository on a local filesystem which the server can
access, and make the repository available over a network.
Chapter 6, Server Configuration covers this process in
detail.
total number of files
find . some_directory|wc -l
list number of files in each directory in detail
#! /usr/bin/python import os import sys def count(p): if not os.path.isdir(p): print "%s\t%d" % (p, 1) return 1 pls = os.listdir(p) s = 0 for d in pls: if os.path.isdir(d): s += count(d) else: s += 1 print "%s\t%d " % (p, s) return s p = sys.argv[1] count(p)
4. Ubuntu DNS Server Problem
Problem Description: I run Ubuntu 9.04 on my computer and use Wicd (Wired and Wireless Network Manager) to configure network settings. However, sometimes when I use wireless network, Wicd is able to connect to routers (pingable), but it fails to parse domain names. There is something wrong with DNS server.
Tentative Solution: 1) First disable all settings related to DNS inside Wicd, i.e. do not use either static or global DNS server; 2) edit /etc/resolv.conf, add available DNS servers; 3) restart computer. 4) [Optional] sometimes if we configure wicd to automatically connect and use static DNS server, Wicd freezes while setting static server. In this case, we can edit /etc/wireless-settings.conf to disable automatic connection and static DNS server.
5. How to rename files or directories in order to remove white spaces in the filename?
for i in $(ls -1 *|grep " "); do
mv "$i" $(echo $i|sed 's/ /-/g');
done
6. How to backup files (or directories) with tar and 7-zip?
First we create tar balls with the tar utility and then compress the tar balls with the 7z program. If the content of the file is sensitive, you can encrypt it with the internal encryption option in 7z or with GPG. The code is as following:
for i in *; do
tar cfv "$i.tar" "$i" && \
7z a "$i.tar.7z" "$i.tar" && \
# rm -rf "$i" && \
# rm -rf "$i.tar"; done
done
7. how do I output the matching regex pattern in a line?
use grep -o PATTERN.
Wednesday, May 07, 2008
Connecting USC VPN Network in Ubuntu
Surprisingly, this old post still receive visitors occasionally. Right now, If you just want to browse the internet and download some papers, you may try the web svn service: sslvpn1.usc.edu.
[Original Post:]
At USC, when you use computers on campus, you can use directly electronic resources, databases, electronic journals because you are in USC private network. Now suppose that you go back to your apartment off campus or you travel away from USC, how can you get access to those electronic resources that USC pays for? That's where VPN come into place. VPN, also called IP tunneling, is a secure method to access computer resources in a private network. VPN stands for "virtual private network". Generally speaking, USC runs a VPN server which listens to your call in and access request. You need to run a VPN client on your own computer, which connects to the server and offer you access to USC resources as you are in USC private network.
However, ITS only provieds official support of VPN clients for Windows (link)and Mac OS (link). Here we give a VPN solution for linux users (take Ubuntu 8.04 for example).
1. Install Network Manager Applet through the Add/Remove in the Ubuntu menu. (Most time, this applet should be installed defautly; if so, just skip to step 2);
2. Install the VPN plug-in network-manager-vpnc. Open Synaptic Package Manager, search for package network-manager-vpnc and install;
3. Left click the network manager applet (usually in the top right corner of your screen) and select VPN Connections->Configure VPN->Add. Type a name in the Connection Name box, USC VPN for example; In Gateway field, type ; In vpn3k.usc.edu; In Group Name field, type USC. Click the Optional tab, select Override user name, type in your USC account (the same as your USC email) in the textbox below. Click Apply. Close the window titled VPN Connections
4. Left click the network manager applet and select VPN Connections then click on USC connection (USC VPN) to connect. In the above password box, type in your password associated with your USC account; in the below Group password, type GoTrojan. OK, we are done!

This tutorial is based on Ubuntu. I think you can also configure VPN client in Debian, Fedora, OpenSuse and other Linux distrobutions.
References:
1.VPN Client on Ubuntu https://help.ubuntu.com/community/VPNClient
2. Configuring the Cisco VPN 3000 Client (Windows 2000/XP/Vista) http://www.usc.edu/its/vpn/vpn3k47win.html#help
Saturday, May 03, 2008
Fixing Resolution Problem of Ubuntu On Paralles Desktop
After installing Ubuntu 8.04 Hardy Heron in Parallels Desktop on my Macbook Pro, the default resolution is 1024*768. I want to use my Macbook pro's 1440*900 full resolution. I tried to use System->Preference->Screen Resolution, but there are not 1440*900 at all.
Solution
Basic idea: The problem arises because Ubuntu fails to detect the settings of my monitor automatically. Then can I mannually modify xorg.conf to set the right resolution? Let's go!
Open up a terminal. First Backup the original xorg.conf
Next open, open xorg.conf with your favorite editor
sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf.backup
sudo vi /etc/X11/xorg.conf
Search the section "Screen" like below.
Probabably your file contains more lines similar to the following
Section "Screen"
Identifier "Default Screen"
Device "Generic Video Card"
Monitor "Generic Monitor"
EndSection
Note the line "Modes "1024x768" "800x600" "640x480"". It says that there are three different kinds resolutions, but our desired resolution 1440x900 is omitted. So we can simply add this resolution option. It is like the following after modification
SubSection "Display"
Depth 24
Modes "1024x768" "800x600" "640x480"
EndSubSection
It’ll appear several times throughout the file. Each time you see it, just add your desired resolution (in your case, 1440×900).
SubSection "Display"
Depth 24
Modes "1440x900" "1024x768" "800x600" "640x480"
EndSubSection
If your file doesn't contain a similar Subsection "Display" inside the Section "Screen" (as shown above), you just add the Subsection "Display" yourself. And th final result looks like
Finally save the above modifications. Restart your X session by pressing Ctrl-Atl-Breakspace (or reboot your ubuntu), it just works!
Section "Screen"
Identifier "Default Screen"
Device "Generic Video Card"
Monitor "Generic Monitor"
DefaultDepth 24
SubSection "Display"
Depth 1
Modes "1440x900" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 4
Modes "1440x900" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 8
Modes "1440x900" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 15
Modes "1440x900" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 16
Modes "1440x900" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 24
Modes "1440x900" "1024x768" "800x600" "640x480"
EndSubSection
EndSection
If you encounter total messy after this modificaion, don't panic because you still have the backup of the original xorg.conf!
Reference
1. http://gonz.wordpress.com/2007/09/22/fixing-screen-resolution-on-ubuntu-linux-in-parallels-desktop/
2. http://www.simplehelp.net/2007/04/30/how-to-increase-the-screen-resolutions-available-to-ubuntu-while-running-in-parallels-for-os-x/
Thursday, April 17, 2008
Installing R in Suse SLED 10.1
"At first I tried SUSE's install software application, but it can't find R in its repository. Then I downloaded the rpm package of R for SUSE 10.1 from CRAN mirrors, and tried install software application again. But it can not resolve dependencies. At last I ran rpm -i R-base-2.6.1-3.1.x86_64.rpm from terminal. It said it needs libgfortran.
OK, I downloaded and installed libgfortran package, and then tried rpm -i R-base-2.6.1-3.1.x86_64.rpm again. This time it needed base. I downloaded base package and try to install it by running rpm -i base-1.3.6-1mdv2008.0.noarch.rpm (I am not sure this is the right package for my computer), butit needs apache-mod_php, apache-mod_ssl, php-mysql, etc. I have to give up."
Also it seems difficult to me to compile R from source code because the package dependency is so complex.
Finally I figured out a trick: we can run windows version R in a linux with Wine. First go to http://www.winehq.org/. download and install wine. And then grab a Windows installer of R and install it. It works, either basic computation or graphic display. But there is a little problem as shown in the following graph: the cursor overlaps with the text.

ps: Another by-product is that I can play starcraft on that Linux machine with a big display.
Reference:
1. Stuff I've learned about Wine
Saturday, April 05, 2008
Anti RSI Software
It is helpful to use more human-friendly mouse and keyboard, comfortable chairs and desks and pleasant work space; however we easily forget how long we use a computer when entirely concertrating on the work. Anti-RSI software can reminds us regular breaks and micropause .
Yun Fang recommended Workpace software to me yesterday. It offers a 30-day trial version, but charges a fee after that period. I found two alternative free anti-RSI software: Workrave for Windows and Linux and AntiRSI for Mac OS.
http://www.workrave.org/welcome/
http://tech.inhelsinki.nl/antirsi/
Reference:
Alleviate RSI the Hacker Way
Saturday, March 01, 2008
Synchronization Between Linux, Mac & Windows
Let me do the research.
My situation is as following:
I run SUSE Linux on the desktop in my lab, which is supposed to running all the time; Also I have a desktop at home running windows xp and finally my macbook laptop. My first priority is to sync between mac and linux for I usc them heavily; and second between mac and windows. Also since I use computer
References
Sync folders between a Mac and PC?
2.
How to mount a Windows shared folder on your Mac
Geek to Live: Mirror files across systems with rsync
http://lifehacker.com/software/mac-os-x/how-to-access-a-macs-files-on-your-pc-247541.phpHow to set up a home FTP server
http://ceitl.zanestate.edu/blog/archives/2005/10/synchronizing-files-across-computers-and-platforms/Geek to Live: Automatically back up your hard drive
http://everythinglinux.org/rsync/Passwordless SSH Login
http://www.hackinglinuxexposed.com/articles/20021226.html
http://linuxmafia.com/%7Erick/linux-info/filesync.html
Monday, January 14, 2008
Synthetic Biology
the four challenges that greatly limit engineering biology today are 1)biological complexity; 2)the tedious and unreliable construction and characterization of synthetic biological systems; 3)the spontaneous variation of biological systems; and 4) evolution.
Lessons from the past
standardization
Registry of Standard Biological Parts: http://parts.mit.edu/registry/index.php/Main_Page
decoupling;
separation of deign and implementation
for example, one group design useful DNA sequences and another group synthesize the piece of DNA chemically. (it seems possible now)
abstraction
design of reproducing machines
reliable computing with unreliable components
error detection & correction mechanism
self-replicating automata
additional reading:
Elowitz, M. B. & Leibler, S. A synthetic oscillatory network of transcriptional
regulators. Nature 403, 335–-338 (2000)
Sprinzak, D. & Elowitz, M. B. Reconstruction of genetic circuits. Nature
doi:10.1038/nature04335
Sunday, November 25, 2007
How to read and write NTFS partition in Mac OS X 10.5 Leopard
1. Download and install MacFUSE for Mac OS X 10.5This approach work on my Mac OS X 10.5 + 10.5.1 updates and Windows XP SP2 with NTFS partition on MacBook Pro (Model Identifier MacBookPro3,1).
2. Download and install NTFS-3g for Mac OS
3. Restart! If you are lucky you can try read and write your Windows' NTFS partition now.
Before you decide to proceed, google "read write NTFS Mac OS X leopard" to be informed of newest advancement and check for latest versions of MacFUSE and NTFS-3g.
Reference
1. MacFUSE http://code.google.com/p/macfuse/
2. NTFS-3g http://www.ntfs-3g.org/
3. NTFS-3g for Mac OS http://macntfs-3g.blogspot.com/
4. Filesystem in Userspace http://en.wikipedia.org/wiki/Filesystem_in_Userspace
5. Filesystem in Userspace http://fuse.sourceforge.net/wiki/index.php/FileSystems
6. NTFS on your Mac http://www.tuaw.com/2007/11/19/ntfs-on-your-mac-two-ways/
Monday, March 12, 2007
Modeling Biomedical Networks
If the rate of change of all variables (concentrations of matters) are constant we get a steady state. If Additionally all reactions fluxes are zero, we have an equilibrium.
Calculating steady state
There are several numerical methods to calculate steady state, such as improved Newton method, forward integration and backward integration. However none of them are perfect even to find a steady state in complex systems, which may have several steady states.
Metabolic Control Analysis
MCA describes how the systems reacts to changes of parameters. Elasticities describes how the reaction rates depend on the metabolite concentrations. Control coefficients describes how the systems behavior depend on the reaction rates
References:
http://projects.eml.org/downloads/copasi/CopasiTutorial.pdf
Wednesday, March 07, 2007
Install Matlab R2006b
SimBiology extends MATLAB with tools for modeling, simulating, and analyzing biochemical pathways. You can create your own block diagram model using predefined blocks. You can manually enter in species, parameters, reactions, rules, kinetic laws, and units, or read in Systems Biology Mark-Up Language (SBML) models. SimBiology lets you simulate a model using stochastic or deterministic solvers and analyze your pathway with tools such as parameter estimation and sensitivity analysis.First get the following MATLAB ISO images at ftp://pxe/software/Matlab2006b (perhaps only available for LAN of USTC)
mount these images and enter the directory where you want to install matlab, create a matlab directory ($MATLAB).
run CD1/install. The graphic interface is easy to complete.
When I finished the normal install and tried to run matlab. It poped a very lengthy error message java.lang.ExceptionInInitializerError at com.mathworks.mde.filebrowser.FileBrowser.
and collapsed thereafter. But if I run matlab -nojvm, it worked normally.
Solution: the java compiler that comes together with MATLAB caused the above error. Replace it with my own version of java (jre1.5.0_06)
cd $MATLAB/sys/javaAnd then MATLAB works now. Bingo!
mv java java-backup
ln -s path_of_your_own_java java
PS: kkk recommended another standalone software, Copasi, to build and simulate biomedical networks. Have a look at it.
COPASI is a software application for simulation and analysis of biochemical networks. COPASI — a COmplex PAthway SImulator. Bioinformatics 22, 3067-74.
Current Features:
- Stochastic and deterministic time course simulation
- Steady state analysis (including stability)
- Metabolic control analysis / sensitivity analysis
- Elementary mode analysis
- Mass conservation analysis
- Calculation of Lyapunov exponents
- Parameter scans
- Optimization of arbitrary objective functions
- Parameter estimation using data from time course and/or steady state experiments
- Sliders for interactive parameter changes
- Global parameter to change multiple kinetic rates at once
- Imports and exports SBML (export only in level 2 version 1, import all levels)
- Loads Gepasi files
- Export in Berkeley Madonna format and C source code of the ODE system generated from the chemical reactions
- Versions for MS Windows, Linux, OS X, and Solaris SPARC
- Command line version for batch processing
- Visit this page often, new releases will contain many more features!
Still No Sense of Signaling Network Research
After I realized the above idea, I decided to read systematically publications in this area. Today I am reading the Science STKE Signaling Breakthroughs of the Year. And now another list of paper to be read (The number of papers in this list is increasing expotentially, I don't know when can I have my sense of them)
[1]G. Altan-Bonnet, R. N. Germain, Modeling T cell antigen discrimination based on feedback control of digital ERK responses. PLoS Biol. 3, e356 (2005).[CrossRef][Medline]
[2]J. R. Pomerening, S. Y. Kim, J. E. Ferrell, Jr., Systems-level dissection of the cell-cycle oscillator: Bypassing positive feedback produces damped oscillations. Cell 122, 565–578 (2005).[CrossRef][Medline]
[3]O. Brandman, J. E. Ferrell, Jr., R. Li, T. Meyer, Interlinked fast and slow positive feedback loops drive reliable cell decisions. Science 310, 496–498 (2005).[Abstract/Free Full Text]
Friday, March 02, 2007
Paper Analysis -2007-03-02
A NETWORK RECONSTRUCTION includes a chemically accurate representation of all of the biochemical events that are occurring within a defined signalling network, and incorporates the interconnectivity and functional relationships that are inferred from experimental data.This article give a enlightening theoretical analysis of signal transduction networks: the order of magnitude of numbers of network components (receptor, kinase, phophatase), the order of magnitude of interconnectivity(~2.5 degree of interconnectivity per component). We can use Combinatorial Complexity to characterize this idea. The catalog of network components without post-translational modification can be inferred from the results the genome annotation. The spectrom of network components after PTM and protein-protein interaction during varies states of the network is expected to be assayed with future proteomic experimental techniques (though I feel passive with expectation). But what use or what consequences of these large potential spectrum of various network components means?
The following paper it refers may be worth reading.
[1]
Papin, J. A. & Palsson, B. O. The JAK–STAT signaling network in the human B-cell: an extreme signaling pathway analysis. Biophys. J. 87, 37–46 (2004).
[2]
Resat, H., Wiley, H. S. & Dixon, D. A. Probability-weighted dynamic Monte Carlo method for reaction kinetics simulations. J. Phys. Chem. B 105, 11026–11034 (2001)
[3]
Bhalla, U. S. & Iyengar, R. Emergent properties of networks of biological signaling pathways. Science 283, 381–387 (1999).
Describes some of the first large-scale analyses of signalling reactions.
[4]
Hoffmann, A., Levchenko, A., Scott, M. L. & Baltimore, D. The IkappaB–NF-kappaB signaling module: temporal control and selective gene activation. Science 298, 1241–1245 (2002).
Shows the powerful integration of mathematical modelling with experimental investigation
[5]
Lee, E., Salic, A., Kruger, R., Heinrich, R. & Kirschner, M. W. The roles of APC and Axin derived from experimental and theoretical analysis of the Wnt pathway. PLoS Biol. 1, 116–132 (2003).
[6]
Prill, R., Iglesias, P.A. and Levchenko, A. Dynamic Properties of Small Regulatory Motifs Contribute to Biological Network Organization. PLoS Biology 3(11): e343 (2005)
[7]
Sivakumaran, S., Hariharaputran, S., Mishra, J. & Bhalla, U. S. The database of quantitative cellular signaling: management and analysis of chemical kinetic models of signaling networks. Bioinformatics 19, 408–415 (2003)
Thursday, March 01, 2007
Omics is Just a Startup
Now besides proteomics and genomics, here comes the metabolomics, with similar promising declarations. As the lates Nature essay (Meet the human metabolome)states,
Metabolomics is the study of the raw materials and products of the body's biochemical reactions, molecules that are smaller than most proteins, DNA and other macromolecules. The aim is to be able to take urine, blood or some other body fluid, scan it in a machine and find a profile of tens or hundreds of chemicals that can predict whether an individual is on the road to a disease, say, or likely to experience side-effects from a particular drug.In fact, researchers in metabolomics are even more optimistic, declaring that
Small changes in the activity of a gene or protein (which may have an unknown impact on the workings of a cell) often create a much larger change in metabolite levels particular concentrations and combinations can reveal something about drugs or diseaseHowever, I am suspecious about their promise. First, considering the great diversity of metabolites in human fluids, we still have not a powerful enough assay to identify the all metabolite in a high-throughout manner and measure their concentrations. Second, the changes in the metabolome is more susceptible to enviromental factors, thus it will be difficult to tell significant changes related to human diseases from temporal fluctuations.
Anyway, let be a little optimistic, omics is just a startup!
Monday, February 05, 2007
Owe Ohler
Ohler U, Shomron N, Burge CB (2005) Recognition of Unknown Conserved Alternatively Spliced Exons. PLoS Comput Biol 1(2): e15 doi:10.1371/journal.pcbi.0010015
Ohler has scientific collaboration with Christopher B. Burge, from MIT, probably a BIG guy in this area. Pay attention to him.
What use is the identification of alternative splicing sites of. The author says that "The identification of such variants has until recently relied solely on the sequencing and comparison of expressed sequence tags (ESTs), but the number of available ESTs is not large enough to cover all variants under all conditions" According a Nature Genetics Review, which I reviewed in last post, the development of microarray platform for finding unknown exons are on the way. Probably, even a microarray experiment can not still covers all variants under all conditions. Thus a preliminary computational prediction gives many possible alternative splicing sites, among which many may be false positive, which can be tested by a microarray experiment. Such prediction may also help the design of the array.
Method: pair hidden Markov model
Patterns of flanking sequence conservation and a characteristic upstream motif for microRNA gene identification RNA (2004), 10:1309-1322
Quantification of transcription factor expression from Arabidopsis images Bioinformatics 2006 22(14):e323-e331; doi:10.1093/bioinformatics/btl228In spite of the great success of microarray technique in gene expression profiling, it fails to detect spatial features of gene expression, thus the confocal microscopy can also provide quantitative information of gene expression with greater spatial and temporal resolution. This paper describes a software protocol of analyzing confocal microscopy images. (How the high-throughput is achieved?)
imagine registration
GFP transcriptional fusion GFP serves as marker of mRNA expression level
GFP translational fusion



