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Mapping cone photopigment optical density
Journal of the Optical Society of America A, 1993The distribution of cone photopigment across the retina affects the amount of light captured by cones at each retinal location. Cone photopigment optical density is measured in two ways, with reflectometry and/or with color matching. Color matching measures a higher optical density than does reflectometry.
A E, Elsner, S A, Burns, R H, Webb
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Interpretation of electron density maps
1985Publisher Summary This chapter presents the indications and strategies for interpretation of protein maps at lower resolution or with less accurate phasing. The resolution level around 5–6 A is one of the traditional milestones in the solution of a protein structure: it is a low point in most radial distributions of diffraction intensity, it is ...
J S, Richardson, D C, Richardson
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The Cartographic Journal, 1987
AbstractAn automated mapping technique, termed unit-vector density mapping, is introduced as a new method of displaying continuous surface vector quantities. With this graphic procedure, the density of short standard-length line segments (unit-vectors) with, or without, arrowheads represents geographical magnitudes and unit-vector orientation shows ...
Stephen J. Lavin, Randall S. Cerveny
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AbstractAn automated mapping technique, termed unit-vector density mapping, is introduced as a new method of displaying continuous surface vector quantities. With this graphic procedure, the density of short standard-length line segments (unit-vectors) with, or without, arrowheads represents geographical magnitudes and unit-vector orientation shows ...
Stephen J. Lavin, Randall S. Cerveny
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Canadian Mathematical Bulletin, 2010
AbstractLet R be a dense subring of End(DV), where V is a left vector space over a division ring D. If dimDV = ∞, then the range of any nonzero polynomial ƒ (X1, … , Xm) on R is dense in End(DV). As an application, let R be a prime ring without nonzero nil one-sided ideals and 0 ≠ a ∈ R. If a f (x1, … , xm)n(xi) = 0 for all x1, … , xm ∈ R, where n(xi )
Chuang, Chen-Lian, Lee, Tsiu-Kwen
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AbstractLet R be a dense subring of End(DV), where V is a left vector space over a division ring D. If dimDV = ∞, then the range of any nonzero polynomial ƒ (X1, … , Xm) on R is dense in End(DV). As an application, let R be a prime ring without nonzero nil one-sided ideals and 0 ≠ a ∈ R. If a f (x1, … , xm)n(xi) = 0 for all x1, … , xm ∈ R, where n(xi )
Chuang, Chen-Lian, Lee, Tsiu-Kwen
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Square-Density Increasing Mappings
2015The square conjecture claims that the number of distinct squares, factors of the form xx, in a word is at most the length of the word. Being associated with it, it is also conjectured that binary words have the largest square density. That is, it is sufficient to solve the square conjecture for words over binary alphabet.
Florin Manea, Shinnosuke Seki
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2002
When everything has been done to make the phases as good as possible, the time has come to examine the image of the structure in the form of an electron-density map. The electron-density map is the Fourier transform of the structure factors (with their phases). If the resolution and phases are good enough, the electron-density map may be interpreted in
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When everything has been done to make the phases as good as possible, the time has come to examine the image of the structure in the form of an electron-density map. The electron-density map is the Fourier transform of the structure factors (with their phases). If the resolution and phases are good enough, the electron-density map may be interpreted in
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Wavelet analysis of electron-density maps
Acta Crystallographica Section D Biological Crystallography, 2000The wavelet transform is a powerful technique in signal processing and image analysis and it is shown here that wavelet analysis of low-resolution electron-density maps has the potential to increase their resolution. Like Fourier analysis, wavelet analysis expresses the image (electron density) in terms of a set of orthogonal functions.
P, Main, J, Wilson
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Visualizing density maps with UCSF Chimera
Journal of Structural Biology, 2007We describe methods for interactive visualization and analysis of density maps available in the UCSF Chimera molecular modeling package. The methods enable segmentation, fitting, coarse modeling, measuring and coloring of density maps for elucidating structures of large molecular assemblies such as virus particles, ribosomes, microtubules, and ...
Thomas D, Goddard +2 more
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Density-based clustering with topographic maps
IEEE Transactions on Neural Networks, 1999A new unsupervised competitive learning rule is introduced, called the kernel-based Maximum Entropy learning Rule (kMER), for equiprobabilistic topographic map formation. The application envisaged is density-based clustering. An empirical study is conducted to compare the clustering performance of kMER with that of a number of other unsupervised ...
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Kernel-Based Density Map Generation for Dense Object Counting
IEEE Transactions on Pattern Analysis and Machine Intelligence, 2022Jia Wan, Qingzhong Wang, Antoni B Chan
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