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Alexandre Matov

Publications and source records attributed to Alexandre Matov.

3 recordsLinked to original sources

Analysis of Unstructured High-Density Crowded Scenes for Crowd Monitoring

We are interested in developing an automated system for detection of organized movements in human crowds. Computer vision algorithms can extract information from videos of crowded scenes and automatically detect and track groups of individuals undergoing organized motion that represents an anomalous behavior in the context of conflict aversion. Our system can detect organized cohorts against the background of randomly moving objects and we can estimate the number of participants in an organized cohort, the speed and direction of motion in real time, within three to four video frames, which is less than one second from the onset of motion captured on a CCTV. We have performed preliminary analysis in this context in biological cell data containing up to four thousand objects per frame and will extend this numerically to a hundred-fold for public safety applications. We envisage using the existing infrastructure of video cameras for acquiring image datasets on-the-fly and deploying an easy-to-use data-driven software system for parsing of significant events by analyzing image sequences taken inside and outside of sports stadiums or other public venues. Other prospective users are organizers of political rallies, civic and wildlife organizations, security firms, and the military. We will optimize the performance of the software by implementing a classification method able to distinguish between activities posing a threat and those not posing a threat.

cs.CV

Mitosis, Cytoskeleton Regulation, and Drug Resistance in Receptor Triple Negative Breast Cancer

During cell division, the receptor triple-negative MDA-MB-231 mitotic spindles are the largest in comparison to other BC cell lines. Many of the MDA-MB-231 spindles exhibit rapid lateral twisting during metaphase, which remains unaffected by knockdown of the oncogene Myc and treatment with inhibitors of the serine/threonine-protein kinase B-Raf and the epidermal growth factor receptor (EGFR), alone or in any combination. The MDA-MB-231 cells are the most aggressive and rapidly form metastatic tumors in xenograft transplant models, and exhibited very high proliferation rates when plated as three-dimensional cultures in Matrigel. Quantitative image analysis of microtubules (MTs) in six BC cell lines - MDA-MB-231 (receptor negative), HCC-1143 (receptor negative), HCC-3153 (receptor negative), ZR75B (estrogen receptor-positive), LY2 (progesterone receptor-positive), HCC-1428 (estrogen receptor-positive, progesterone receptor-positive) - demonstrated that the rotational spindle rocking of MDA-MB-231 cells during metaphase appears coupled with a significant increase in MT polymerization rates during interphase, which likely shortens interphase and accelerates cell cycle progression and mitotic entry. Unlike the uniform treadmilling rates of about 21 um/min in kinetochore MTs during metaphase we measured across cell lines, MDA-MB-231 cells in interphase exhibit the fastest MT polymerization dynamics of about 19 um/min and this is coupled with abnormal mitotic spindle oscillations of almost 30 um/min. This aberrant behavior in MDA-MB-231 spindles may represent a therapeutically targetable disrupted mechanism of spindle positioning in receptor triple-negative breast cancer (TNBC) cells leading to tumor aggressiveness. In this manuscript, we outline a strategy for the selection of the most optimal tubulin inhibitor based on the ability to affect MT dynamics.

q-bio.QM

Real-Time Image Analysis Software Suitable for Resource-Constrained Computing

Methods: We have developed a software suite (DataSet Tracker) for real-time analysis designed to run on computers, smartphones, and smart glasses hardware and suitable for resource-constrained, on-the-fly computing in microscopes without internet connectivity; a demo is available for viewing at datasetanalysis.com. Our objective is to present the community with an integrated, easy to use by all, tool for resolving the complex dynamics of the cytoskeletal meshworks, intracytoplasmic membranous networks, and vesicle trafficking. Our software is optimized for resource-constrained computing and can be installed even on microscopes without internet connectivity. Results: Our computational platform can provide high-content analyses and functional secondary screening of novel compounds that are in the process of approval, or at a pre-clinical stage of development, and putative combination therapies based on FDA-approved drugs. Importantly, dissecting the mechanisms of drug action with quantitative detail will allow the design of drugs that impede relapse and optimal dose regimens with minimal harmful side effects by carefully exploiting disease-specific aberrations. Conclusions: DataSet Tracker, the real-time optical flow feature tracking software presented in this contribution, can serve as the base module of an integrated platform of existing and future algorithms for real-time cellular analysis. The computational assay we propose could successfully be applied to evaluate treatment strategies for any human organ. It is our goal to have this integrated tool approved for use in the clinical practice.

q-bio.QM