On line background modeling for moving object segmentation in dynamic scenes

Fast and accurate moving object segmentation in dynamic scenes is the first step in many computer vision applications. In this paper, we propose a new background modeling method for moving object segmentation based on dynamic matrix and spatio-temporal analyses of scenes. Our method copes with some challenges related to this field. A new algorithm is proposed to detect and remove cast shadow. A comparative study by quantitative evaluations shows that the proposed approach can detect foreground robustly and accurately from videos recorded by a static camera and which include several constraints. A Highway Control and Management System called RoadGuard is proposed to show the robustness of our method. In fact, our system has the ability to control highway by detecting strange events that can happen like vehicles suddenly stopped in roads, parked vehicles in emergency zones or even illegal conduct such as going out from the road. Moreover, RoadGuard is capable of managing highways by saving information about the date and time of overloaded roads.     

A new approach of data clustering using a flock of agents

This paper presents a new bio-inspired algorithm (FClust) that dynamically creates and visualizes groups of data. This algorithm uses the concepts of a flock of agents that move together in a complex manner with simple local rules. Each agent represents one data. The agents move together in a 2D environment with the aim of creating homogeneous groups of data. These groups are visualized in real time, and help the domain expert to understand the underlying structure of the data set, like for example a realistic number of classes, clusters of similar data, isolated data. We also present several extensions of this algorithm, which reduce its computational cost, and make use of a 3D display. This algorithm is then tested on artificial and real-world data, and a heuristic algorithm is used to evaluate the relevance of the obtained partitioning.     

Thymoquinone effects on DMH-induced erythrocyte oxidative stress and haematological alterations during colon cancer promotion in rats

The effect of thymoquinone (TQ), the abundant component of black cumin seed (Nigella sativa) oil extract, was evaluated on 1,2-dimethylhydrazine (DMH)-induced erythrocyte oxidative stress and haematological perturbations during colon cancer promotion in rats. Two TQ approaches, the pre- and post-treatment, were used. DMH promoted erythrocyte oxidative damage in rats by enhancing lipid peroxidation (30%) and decreasing antioxidant enzymes activities (20–35%). This was associated with the decline of erythrocyte count, haemoglobin concentration and haematocrit (20%) and the count increase of white blood cell (60%) and platelet (180%). TQ pre-treatment repaired DMH-induced erythrocyte oxidative stress, anaemia, leukocytosis, and thrombocytosis and allowed a 60% of tumour incidence decline. TQ post-treatment exerted a slight effect on erythrocyte oxidative stress and reduced colon cancer incidence by 30% only. Thus, TQ efficacy in preventing DMH-induced colon cancer promotion was related to its virtue antioxidant effect on erythrocyte oxidative stress.     

Chemical composition,antimicrobial potential against cariogenic bacteria and cytotoxic activity of Tunisian Nigella sativa essential oil and thymoquinone

We investigate in this work the chemical composition by GC–EIMS, the antibacterial and the cytotoxic activities of Tunisian Nigella sativa essential oil and its bioactive compound, thymoquinone, were tested against various clinical cariogenic bacteria (n = 30). Eighty-four compounds were identified in the essential oil. The major one was p-cymene (49.48%) whereas thymoquinone represented only 0.79%. The essential oil (2.43 mg/disc) containing only 3.35 μg of thymoquinone showed pronounced dose dependant antibacterial activity against Streptococcus mitis, Streptococcus mutans, Streptococcus constellatus and Gemella haemolysans (15.5 ± 0.707 mm). However, pure thymoquinone compound (150 μg/disk) was active against all the studied strains especially S. mutans and S. mitis (24.5 ± 0.71 and 22 ± 1.41 mm inhibition zones, respectively).     

On the Stability of a Degenerate Wave Equation Under Fractional Feedbacks Acting on the Degenerate Boundary

Journal of Dynamical and Control Systems - In this work, we are concerned with the study of stabilization of one-dimensional weakly degenerate wave equation utt ? (xγux)x = 0 with x...     

Cellular uptake and cytotoxic impact of chemically functionalized and polymer-coated carbon nanotubes

The impact of nanomaterials such as carbon nanotubes on biological matter is a topic of increasing interest and concern and requires a multifaceted approach to be resolved. A modified cytotoxic (lactate dehydrogenase (LDH)) assay is developed in an attempt to offer a valid and reliable methodology for screening carbon nanotube toxicity in vitro. Two of the most widely used types of surface-modified multiwalled carbon nanotubes (MWNTs) are tested: ammonium-functionalized MWNTs (MWNT-NH3+ ) and Pluronic F127 coated MWNTs (MWNT:F127). Chemically functionalized MWNTs show significantly greater cellular uptake into lung epithelial A549 cells compared to the non-covalently Pluronic F127-coated MWNTs. In spite of this, MWNT:F127 exhibit enhanced cytotoxicity according to the modified LDH assay. The validity of the modified LDH assay is further validated by direct comparison with other less reliable or accurate cytotoxicity assays. These findings indicate the reliability of the modified LDH assay as a screening tool to assess carbon nanotube cytotoxicity and illustrate that high levels of carbon nanotube cellular internalization do not necessarily lead to adverse responses.     

Assigning routes and wavelengths for collaboration over optical networks

The Routing and Wavelength Assignment problem is investigated in the context of collaboration where tools are shared and used simultaneously over a fiber optic network. Both online and offline versions are discussed, with and without using time as a parameter for scheduling purposes, and including the case where the network is used to carry time-multiplexed traffic. Also, the problem of rescheduling a blocked demand is studied. Several solutions based on Integer Linear Programs (ILP) and heuristics are proposed, implemented and their performance compared. The offline case is solved using two types of ILPs: link and path formulations. ILPs are also proposed for the online problem in addition to heuristic algorithms. While the link formulations give optimal solutions, they take a long time to solve and thus they can only be used for small problems. Path formulations and heuristics scale better but at the expense of optimality. The online approach is recommended when the resort to an offline approach is forbidden by the size of the problem.     

Background subtraction practice in X-ray reflectivity reciprocal space mapping and its influence on the structural parameters of thin films

Background subtraction practice in X-ray reflectivity reciprocal space mapping (XRRSM) is described and compared to the traditional specular reflectivity. XRRSM allows determining a more precise contribution of background to the reflectivity signal which manifests itself in an improvement of the resolution of interference fringes. Data analysis and influence of background subtraction determined by two methods on the structural parameters of thin film are discussed using simulated X-ray reflectivity.