Zeiss LSM 880, Руководство по эксплуатации

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CHAPTER 1 - SYSTEM OPERATION
LSM 880 Center Screen Area / Image Containers - Display and Image Analysis ZEISS
10/2014 V_01 000000-2071-464 475
6.11.2 Quantitative Colocalization Parameters Shown in the Data Table
−
No. of pixels in image ROI or scatter region
−
Area / relative area
of image ROI or scatter region
−
Mean intensities / SD
within image ROI or scatter region
−
Colocalization coefficients
−
Weighted colocalization coefficients
−
Overlap coefficient after Manders
−
Correlation coefficients
(R and R
2
)
6.11.3 Colocalization Coefficients
total Ch
coloc Ch
pixels
pixels
c
, 1
, 1
1
=
total Ch
coloc Ch
pixels
pixels
c
, 2
, 2
2
=
−
Relative number of colocalizing pixels in channel 1 or 2, respectively, as compared to the total
number of pixels above threshold.
−
Value range 0 – 1 (0: no colocalization, 1: all pixels colocalize)
−
All pixels above background count
irrespective of their intensity.
Weighted colocalization coefficients
∑
∑
=
i
i,total
i
i,coloc
Ch
Ch
M
1
1
1
∑
∑
=
i
i,total
i
i,coloc
Ch
Ch
M
2
2
2
−
Sum of intensities of colocalizing pixels in channel 1 or 2, respectively, as compared to the overall
sum of pixel intensities above threshold and in this channel.
−
Value range 0 – 1 (0: no colocalization, 1: all pixels colocalize)
−
Bright pixels contribute more than faint pixels
Correlation coefficient, Pearson´s correlation coefficient
∑ ∑
∑
− −
− −
=
i i
aver i aver i
i
aver i aver i
p
Ch Ch Ch Ch
Ch Ch Ch Ch
R
2 2
) 2 2 ( * ) 1 1 (
) 2 2 ( * ) 1 1 (
−
Provides information on the intensity distribution within the colocalizing region
−
Value range -1 to +1
-1,+1: all pixels are found on straight line in the scatter diagram
0: pixels in scattergram distribute in a cloud with no preferential direction