Vadim Ratner

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The conflicting demands for simultaneous low-pass and high-pass processing, required in image denoising and enhancement, still present an outstanding challenge, although a great deal of progress has been made by means of adaptive diffusion-type algorithms. To further advance such processing methods and algorithms, we introduce a family of second-order (in(More)
Molecular mechanisms underlying programs of cell proliferation, differentiation and apoptosis are now under intensive investigation. Recent studies strongly suggest that triggering of these programs depends on the cell cycle control. Integrative approaches such as computer modeling are needed to analyze different modes of the complex dynamics of the(More)
Extracting nuclei is one of the most actively studied topic in the digital pathology researches. Most of the studies directly search the nuclei (or seeds for the nuclei) from the finest resolution available. While the richest information has been utilized by such approaches, it is sometimes difficult to address the heterogeneity of nuclei in different(More)
It was recently shown that the brain-wide cerebrospinal fluid (CSF) and interstitial fluid exchange system designated the 'glymphatic pathway' plays a key role in removing waste products from the brain, similarly to the lymphatic system in other body organs(1,2). It is therefore important to study the flow patterns of glymphatic transport through the live(More)
Image denoising and enhancement problems have many physical analogues that highlight new approaches to novel solutions. One such solution, based on viewing the image as elastic sheet, is presented. A processing scheme for grayscale images is outlined and further considered in the context of color images. Preliminary analysis and simulations on noisy images(More)
Image denoising and enhancement problems have many physical analogues that highlight new approaches to novel solutions. One such solution, based on viewing the image as elastic sheet, is presented. A processing scheme for grayscale images is outlined and further considered in the context of color images. Preliminary analysis and simulations on noisy images(More)
Diffusion-type algorithms have been integrated in recent years successfully into the toolbox of image processing. We introduce a new more flexible and powerful family of parabolic-hyperbolic partial differential equations (PDEs) that somewhat resembles the structure of the parabolic diffusion equation, but incorporates the second order derivative in time.(More)
Digital histopathological images provide detailed spatial information of the tissue at micrometer resolution. Among the available contents in the pathology images, meso-scale information, such as the gland morphology, texture, and distribution, are useful diagnostic features. In this work, focusing on the colon-rectal cancer tissue samples, we propose a(More)
It was recently shown that the brain-wide cerebrospinal fluid (CSF) and interstitial fluid exchange system designated the ‘glymphatic pathway’ plays a key role in removing waste products from the brain, similarly to the lymphatic system in other body organs . It is therefore important to study the flow patterns of glymphatic transport through the live brain(More)
The recently-proposed family of Telegraph-Diffusion (TeD) operators is analyzed in the context of image enhancement. Stability of such schemes in terms of energy convergence is investigated and compared with that of the widely-used diffusion-based schemes, thereby resolving the Perona-Malik paradox. The results indicating stability are further generalized(More)