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Xianjun Dong
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Simple note for github vs. Rstudio
Having used both Rstudio and GitHub for a while, but never thought to combine them together. Hadley Wickham already put a detailed instruction on how to link GitHub with Rstudio ( http://r-pkgs.had.co.nz/git.html ). I just list few quick note from my own ex...

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remove and disable .DS_Store in mounted disk
Do you see this when you want to extend your path by typing the TAB key? What are those .DS_Store files? They are generated by MacOS (see [1] for detail). Because I mount my remote disk via SMB, MacOS Finder will generate such a configure file whenever you ...

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IBS vs. IBD
Regarding your question what's IBD and IBS, here is my understanding: A SNP (or a segment of DNA) is identical by state (IBS) if they have the same alleles in two of more individuals. For example, if person A has genotype A/C at a SNP position while person ...

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Best way to draw heatmap for publication
Here are two tips I can share if you were also working on a big dataset towards a high quality heatmap: 1. Don't generate PDF using pheatmap() or heatmap.2() as (i) the file is unnecessarily SUPER large if you have a lot of data points in the heatmap, so th...

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My 15 practical tips for a bioinformatician
Tips below are based on the lessons I learnt from making mistakes during my years of research. It's purely personal opinion. Order doesn't mean anything. If you think I should include something else, please comment below. Always set a seed number when you r...

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Dopamine is the "Kim Kardashian of molecule" in brain -- I like this!
, and it's interesting to know the impressive people in the Kardashian family.  The main dopaminergic pathways of the human brain. (Wikipedia) References: http://www.slate.com/articles/health_and_science/science/2013/07/what_is_dopamine_love_lust_sex_addict...

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SNP allele coding schema
There are three types of different SNP allele coding schemes (so far). No idea why the scientists have to make things so confusing sometimes... Here you go: TOP/BOT from Illumina : Simply saying, for unambiguous cases (incl. A/G, A/C, T/G, T/C), A is always...

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My note on multiple testing
It's not a shame to put a note on something (probably) everyone knows and you thought you know but actually you are not 100% sure. Multiple testing is such a piece in my knowledge map. Some terms first: - Type I error (false positive) and Type II error (fal...

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DNA and RNA structure
Reference: http://passel.unl.edu/pages/informationmodule.php?idinformationmodule=957882007&topicorder=4&maxto=7 Each strand of DNA double helix is a chain of bases linked to the sugar-phosphate backbone. The two strands are connected with hydrogen bonds. As...
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