A reproducibility-based evaluation procedure for quantifying the differences between MS/MS peak intensity normalization methods

PROTEOMICS ◽  
2011 ◽  
Vol 11 (6) ◽  
pp. 1172-1180 ◽  
Author(s):  
Sven Degroeve ◽  
Niklaas Colaert ◽  
Joël Vandekerckhove ◽  
Kris Gevaert ◽  
Lennart Martens
Author(s):  
I Nyoman Gede Arya Astawa ◽  
I Ketut Gede Darma Putra ◽  
I Made Sudarma ◽  
Rukmi Sari Hartati

One of the factors that affects the detection system or face recognition is lighting. Image color processing can help the face recognition system in poor lighting conditions. In this study, homomorphic filtering and intensity normalization methods used to help improve the accuracy of face image detection. The experimental results show that the non-uniform of the illumination of the face image can be uniformed using the intensity normalization method with the average value of Peak Signal to Noise Ratio (PSNR) obtained from the whole experiment is 22.05314 and the average Absolute Mean Brightness Error (AMBE) value obtained is 6.147787. The results showed that homomorphic filtering and intensity normalization methods can be used to improve the detection accuracy of a face image.


PLoS ONE ◽  
2015 ◽  
Vol 10 (7) ◽  
pp. e0135107 ◽  
Author(s):  
A. Brahim ◽  
J. Ramírez ◽  
J. M. Górriz ◽  
L. Khedher ◽  
D. Salas-Gonzalez

2004 ◽  
Vol 26 (1-2) ◽  
pp. 31-43
Author(s):  
Martial Guillaud ◽  
Dennis Cox ◽  
Anais Malpica ◽  
Gregg Staerkel ◽  
Jasenka Matisic ◽  
...  

Objectives: As part a Program Project to evaluate emerging optical technologies for cervical neoplasia, our group is performing quantitative histopathological analysis of biopsies from 1800 patients. Several methodological issues have arisen with respect to this analysis: (1) Finding the most efficient way to compensate for staining intensity variation with out losing diagnostic information; (2) Assessing the inter‐ and intra‐observer variability of the semi‐interactive data collection; and (3) the use of non‐overlapping cells from the intermediate layer only. Methods: Non‐overlapping quantitatively stained nuclei were selected from 280 samples with histopathological characteristics of normal (199), koilocytosis (37), CIN 1 (18), CIN 2 (10) and CIN 3 (16). Linear discriminant analysis was used to assess the diagnostic information in three different feature sets to evaluate and compare staining intensity normalization methods. Selected feature values and summary scores were used to evaluate intra‐ and inter‐observer variability. Results: The features normalized by the internal subset of the imaged cells had the same discriminatory power as those normalized by the control cells and by both normalization methods seem to have additional discriminatory power over the set of features which do not require normalization. The use of the internal subset decreased the image acquisition time by ∼50% at each center, respectively. The intra‐ and inter‐observer variability was of a similar size. Good performance was obtained by measuring the intermediate layer only. Conclusion: The use of intensity normalization from a subset of the imaged non‐overlapping intermediate layer cells works as well as or better than any of the other methods tested and provides a significant timesaving. Our intra‐ and inter‐observer variability do not seem to affect the diagnostic power of the data. Although this must be tested in a larger data set, the use of intermediate layer cells only may be acceptable when using quantitative histopathology.


PLoS ONE ◽  
2015 ◽  
Vol 10 (6) ◽  
pp. e0130274 ◽  
Author(s):  
A. Brahim ◽  
J. Ramírez ◽  
J. M. Górriz ◽  
L. Khedher ◽  
D. Salas-Gonzalez

NeuroImage ◽  
2020 ◽  
Vol 222 ◽  
pp. 117229 ◽  
Author(s):  
Francisco J. López-González ◽  
Jesús Silva-Rodríguez ◽  
José Paredes-Pacheco ◽  
Aida Niñerola-Baizán ◽  
Nikos Efthimiou ◽  
...  

Author(s):  
Allison M. Thompson ◽  
Kelly G. Stratton ◽  
Lisa M. Bramer ◽  
Nicole S. Zavoshy ◽  
Lee Ann McCue

Cancers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 3000
Author(s):  
Yingping Li ◽  
Samy Ammari ◽  
Corinne Balleyguier ◽  
Nathalie Lassau ◽  
Emilie Chouzenoux

In brain MRI radiomics studies, the non-biological variations introduced by different image acquisition settings, namely scanner effects, affect the reliability and reproducibility of the radiomics results. This paper assesses how the preprocessing methods (including N4 bias field correction and image resampling) and the harmonization methods (either the six intensity normalization methods working on brain MRI images or the ComBat method working on radiomic features) help to remove the scanner effects and improve the radiomic feature reproducibility in brain MRI radiomics. The analyses were based on in vitro datasets (homogeneous and heterogeneous phantom data) and in vivo datasets (brain MRI images collected from healthy volunteers and clinical patients with brain tumors). The results show that the ComBat method is essential and vital to remove scanner effects in brain MRI radiomic studies. Moreover, the intensity normalization methods, while not able to remove scanner effects at the radiomic feature level, still yield more comparable MRI images and improve the robustness of the harmonized features to the choice among ComBat implementations.


Author(s):  
J. S. Wall ◽  
J. P. Langmore ◽  
H. Isaacson ◽  
A. V. Crewe

The scanning transmission electron microscope (STEM) constructed by the authors employs a field emission gun and a 1.15 mm focal length magnetic lens to produce a probe on the specimen. The aperture size is chosen to allow one wavelength of spherical aberration at the edge of the objective aperture. Under these conditions the profile of the focused spot is expected to be similar to an Airy intensity distribution with the first zero at the same point but with a peak intensity 80 per cent of that which would be obtained If the lens had no aberration. This condition is attained when the half angle that the incident beam subtends at the specimen, 𝛂 = (4𝛌/Cs)¼


Author(s):  
Mihir Parikh

It is well known that the resolution of bio-molecules in a high resolution electron microscope depends not just on the physical resolving power of the instrument, but also on the stability of these molecules under the electron beam. Experimentally, the damage to the bio-molecules is commo ly monitored by the decrease in the intensity of the diffraction pattern, or more quantitatively by the decrease in the peaks of an energy loss spectrum. In the latter case the exposure, EC, to decrease the peak intensity from IO to I’O can be related to the molecular dissociation cross-section, σD, by EC = ℓn(IO /I’O) /ℓD. Qu ntitative data on damage cross-sections are just being reported, However, the microscopist needs to know the explicit dependence of damage on: (1) the molecular properties, (2) the density and characteristics of the molecular film and that of the support film, if any, (3) the temperature of the molecular film and (4) certain characteristics of the electron microscope used


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