Question regarding standard deviations

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robraunjp
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Joined: 2011.08.22 21:12

Question regarding standard deviations

#1 Post by robraunjp » 2011.09.30 20:06

Hello
I was studying some published studies with SAXS data and I became really interested in the standard deviations they have.
In the attached figure (SAXS curve for 3 increasingly bigger protein complexes) the deviations in the right hand of the plot (Porod Region?) are really different form those in the left hand part of the plot (larger deviations).
Is there any general interpretation to those deviations (i.e. it is normal for all SAXS plots, or it represents protein flexibility, etc)?

Thank you in advance
R.
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Alex
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#2 Post by Alex » 2012.03.22 01:08

Hi
(i.e. it is normal for all SAXS plots,

yes, it is normal. It is mainly depends on the concentration of your
sample and detector.
or it represents protein flexibility, etc)?
no, it does not.

HTH
Alex

spark
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#3 Post by spark » 2012.03.22 17:46

The scattering intensity drops quickly for q increasing. Less photons are scattered under a higher angle, hence larger signal to noise ratio.

tdgrant1
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#4 Post by tdgrant1 » 2012.03.22 18:11

Keep in mind the y-axis is on a log scale.

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