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What are the spot numbers for the three highest ranking spots?

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What are the "R/G Normalized (Mean)" values for the three highest ranking spots?

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Does it change the ranking of the spots to use the log transformations of the ratios instead of the ratios?

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To demonstrate a different method of visualizing and analyzing microarry data,take a look at the MIT Cancer Genomics Microarray Data Sets . Scroll down to the section entitled "Gene Expression Correlates of Clinical Prostate Cancer Behavior".Click on the first data set, for Prostate tumor and normal samples, entitled "Prostate_TN_final0701_allmeanScale.res". This data set originates fromAffymetrix chips. In this case, the signal is recorded as "A" for absent, "P" for present, and"M" for marginal, as determined by the Affymetrix GeneChip software. The numerical values are scaled average difference units for tumor vs. normalprediction, and these values are also generated by the Affymetrix software. A more complete discussion of gene expression data analysis for AffymetrixGeneChip Arrays can be found at the Affymetrix web site .

So far, the discussion has been primarily about visualizing and quantifying the fluorescence signal from a microarray experiment. However, analysis ofgene expression under experimental conditions versus reference conditions requires determining whether observed differences are significant or not.There are many sources of noise and variability in microarray data, including experimental sources such as image scanning inconsistencies, issues involved incomputer interpretation and quantification of spots, hybridization variables such as temperature and time discrepancies between experiments, andexperimental errors caused by differential probe labeling and efficacy of RNA extraction.In addition, as the size of the sample increases, so does the probability of finding some large differences due to chance. Therefore, statistical analysisis required to show that gene expression differences are real.

There are some complex problems underlying statistical analysis of microarray data, primarily related to the fact that the number of samples is very, verylarge, but the number of times that each measurement is repeated is comparatively very small. (This is due mostly to cost and time issues.)Also, the simplest statistical techniques commonly assume a normal distribution, which cannot necessarily be assumed in microarray experiments. For a detaileddiscussion, D. K. Slonim (3) has authored agood review of the most current approaches to gene expression data analysis.

This tutorial will provide an oversimplified example of the type of statisticalanalysis that needs to be applied to microarray data, using the t-test. For a given gene, A, the gene will have two associated vectors:{a(ref)1, ..., a(ref)n} and {a(exp)1, ..., a(exp)n}, where a(ref) contains n measurements of expression levels under reference conditions and a(exp)contains n measurements of expression levels under experimental conditions.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Bios 533 bioinformatics. OpenStax CNX. Sep 24, 2008 Download for free at http://cnx.org/content/col10152/1.16
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