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Nowadays video surveillance systems are widely deployed in many public places. However, the widespread use of video surveillance
violates the privacy rights of the people. Many authors have addressed the privacy issues from various points of view. In
this paper we propose a novel, on-demand selectively revocable, privacy preserving mechanism. The surveillance video can be
tuned to view with complete privacy or by revoking the privacy of any subset of pedestrians while ensuring complete privacy
to the remaining pedestrians. We achieve this by tracking the pedestrians using a novel Markov chain algorithm with two hidden
states, detecting the head contour of the tracked pedestrians and obscuring their faces using an encryption mechanism. The
detected pedestrian face/head is obscured by encrypting with a unique key derived from a master key for the privacy preservation
purpose. The performance evaluations on many challenging surveillance scenarios show that the proposed mechanism can effectively
and robustly track as well as identify multiple pedestrians and obscure/unobscure their faces/head in real time. 相似文献
34.
Emmanuel Benoist Jean-Jacques Hébrard 《Annals of Mathematics and Artificial Intelligence》2003,37(3):251-272
The enlarged Horn formulas generalize the extended Horn formulas introduced by Chandru and Hooker (1991). Their satisfying truth assignments can be generated with polynomial delay. Unfortunately no polynomial algorithm is known for recognizing enlarged Horn formulas or extended Horn formulas. In this paper we define the class of simple enlarged Horn formulas, a subclass of the enlarged Horn formulas, that contains the simple extended Horn formulas introduced by Swaminathan and Wagner (1995). We present recognition algorithms for the simple enlarged Horn formulas and the simple extended Horn formulas whose complexity is bounded by the complexity of the arborescence-realization problem. 相似文献
35.
Yannis Theodoridis Dimitris Papadias Emmanuel Stefanakis Timos Sellis 《Data & Knowledge Engineering》1998,27(3):2108
This paper defines direction relations (e.g., north, northeast) between two-dimensional objects and shows how they can be efficiently retrieved using B-, KDB- and R- tree-based data structures. Essentially, our work studies optimisation techniques for 2D range queries that arise during the processing of direction relations. We test the efficiency of alternative indexing methods through extensive experimentation and present analytical models that estimate their performance. The analytical estimates are shown to be very close to the actual results and can be used by spatial query optimizers in order to predict the retrieval cost. In addition, we implement modifications of the existing structures that yield better performance for certain queries. We conclude the paper by discussing the most suitable method depending on the type of the range and the properties of the data. 相似文献
36.
Amel Djoudi Rodolfo Molina-Pea Natalia Ferreira Ilaria Ottonelli Giovanni Tosi Emmanuel Garcion Frank Boury 《International journal of molecular sciences》2022,23(20)
Hyaluronic acid (HA) is a Glycosaminoglycan made of disaccharide units containing N-acetyl-D-glucosamine and glucuronic acid. Its molecular mass can reach 10 MDa and its physiological properties depend on its polymeric property, polyelectrolyte feature and viscous nature. HA is a ubiquitous compound found in almost all biological tissues and fluids. So far, HA grades are produced by biotechnology processes, while in the human organism it is a major component of the extracellular matrix (ECM) in brain tissue, synovial fluid, vitreous humor, cartilage and skin. Indeed, HA is capable of forming hydrogels, polymer crosslinked networks that are very hygroscopic. Based on these considerations, we propose an overview of HA-based scaffolds developed for brain cancer treatment, central and peripheral nervous systems, discuss their relevance and identify the most successful developed systems. 相似文献
37.
Gagan Preet Emmanuel T. Oluwabusola Bruce Forbes Milne Rainer Ebel Marcel Jaspars 《International journal of molecular sciences》2022,23(22)
Monkeypox is caused by a DNA virus known as the monkeypox virus (MPXV) belonging to the Orthopoxvirus genus of the Poxviridae family. Monkeypox is a zoonotic disease where the primary significant hosts are rodents and non-human primates. There is an increasing global incidence with a 2022 outbreak that has spread to Europe in the middle of the COVID-19 pandemic. The new outbreak has novel, previously undiscovered mutations and variants. Currently, the US Food and Drug Administration (FDA) approved poxvirus treatment involving the use of tecovirimat. However, there has otherwise been limited research interest in monkeypox. Mitoxantrone (MXN), an anthracycline derivative, an FDA-approved therapeutic for treating cancer and multiple sclerosis, was previously reported to exhibit antiviral activity against the vaccinia virus and monkeypox virus. In this study, virtual screening, molecular docking analysis, and pharmacophore ligand-based modelling were employed on anthracene structures (1-13) closely related to MXN to explore the potential repurposing of multiple compounds from the PubChem library. Four chemical structures (2), (7), (10) and (12) show a predicted high binding potential to suppress viral replication. 相似文献
38.
Elodie Mareux Martine Lapalus Amel Ben Saad Renaud Zelli Mounia Lakli Yosra Riahi Marion Almes Manon Banet Isabelle Callebaut Jean-Luc Decout Thomas Falguires Emmanuel Jacquemin Emmanuel Gonzales 《International journal of molecular sciences》2022,23(18)
ABCB11 is responsible for biliary bile acid secretion at the canalicular membrane of hepatocytes. Variations in the ABCB11 gene cause a spectrum of rare liver diseases. The most severe form is progressive familial intrahepatic cholestasis type 2 (PFIC2). Current medical treatments have limited efficacy. Here, we report the in vitro study of Abcb11 missense variants identified in PFIC2 patients and their functional rescue using cystic fibrosis transmembrane conductance regulator potentiators. Three ABCB11 disease-causing variations identified in PFIC2 patients (i.e., A257V, T463I and G562D) were reproduced in a plasmid encoding an Abcb11-green fluorescent protein. After transfection, the expression and localization of the variants were studied in HepG2 cells. Taurocholate transport activity and the effect of potentiators were studied in Madin–Darby canine kidney (MDCK) clones coexpressing Abcb11 and the sodium taurocholate cotransporting polypeptide (Ntcp/Slc10A1). As predicted using three-dimensional structure analysis, the three variants were expressed at the canalicular membrane but showed a defective function. Ivacaftor, GLP1837, SBC040 and SBC219 potentiators increased the bile acid transport of A257V and T463I and to a lesser extent, of G562D Abcb11 missense variants. In addition, a synergic effect was observed when ivacaftor was combined with SBC040 or SBC219. Such potentiators could represent new pharmacological approaches for improving the condition of patients with ABCB11 deficiency due to missense variations affecting the function of the transporter. 相似文献
39.
Katie L. J. Cederberg Umaer Hanif Vicente Peris Sempere Julien Hdou Eileen B. Leary Logan D. Schneider Ling Lin Jing Zhang Anne M. Morse Adam Blackman Paula K. Schweitzer Suresh Kotagal Richard Bogan Clete A. Kushida Yo-El S. Ju Nayia Petousi Chris D. Turnbull Emmanuel Mignot The STAGES Cohort Investigator Group 《International journal of molecular sciences》2022,23(14)
Obstructive sleep apnea (OSA), a disease associated with excessive sleepiness and increased cardiovascular risk, affects an estimated 1 billion people worldwide. The present study examined proteomic biomarkers indicative of presence, severity, and treatment response in OSA. Participants (n = 1391) of the Stanford Technology Analytics and Genomics in Sleep study had blood collected and completed an overnight polysomnography for scoring the apnea–hypopnea index (AHI). A highly multiplexed aptamer-based array (SomaScan) was used to quantify 5000 proteins in all plasma samples. Two separate intervention-based cohorts with sleep apnea (n = 41) provided samples pre- and post-continuous/positive airway pressure (CPAP/PAP). Multivariate analyses identified 84 proteins (47 positively, 37 negatively) associated with AHI after correction for multiple testing. Of the top 15 features from a machine learning classifier for AHI ≥ 15 vs. AHI < 15 (Area Under the Curve (AUC) = 0.74), 8 were significant markers of both AHI and OSA from multivariate analyses. Exploration of pre- and post-intervention analysis identified 5 of the 84 proteins to be significantly decreased following CPAP/PAP treatment, with pathways involving endothelial function, blood coagulation, and inflammatory response. The present study identified PAI-1, tPA, and sE-Selectin as key biomarkers and suggests that endothelial dysfunction and increased coagulopathy are important consequences of OSA, which may explain the association with cardiovascular disease and stroke. 相似文献
40.
We present an algorithm for automatic spot localization for microarray images with rectangular spot and block packing. As an input, the algorithm requires only the common array design parameters: number of block rows and columns and number of spot rows and columns within each block. It proved to be robust with respect to different types of contamination and can tolerate a high percentage of the missing spots. The validity of the developed algorithm has been tested and confirmed using a large set of images of various designs from different microarray platforms. Comparison with academic and commercial packages has shown that for uncontaminated images our algorithm performs similarly, whereas for certain problematic images it outperforms the other packages.Patent pending. 相似文献