Search results for "COLOR"
showing 10 items of 2721 documents
Road Signs Detection and Reconstruction using Gielis Curves
2012
International audience; Road signs are among the most important navigation tools in transportation systems. The identification of road signs in images is usually based on first detecting road signs location using color and shape information. In this paper, we introduce such a two-stage detection method. Road signs are located in images based on color segmentation, and their corresponding shape is retrieved using a unified shape representation based on Gielis curves. The contribution of our approach is the shape reconstruction method which permits to detect any common road sign shape, i.e. circle, triangle, rectangle and octagon, by a single algorithm without any training phase. Experimental…
Vertex Distinguishing Edge- and Total-Colorings of Cartesian and other Product Graphs
2012
International audience; This paper studies edge- and total-colorings of graphs in which (all or only adjacent) vertices are distinguished by their sets of colors. We provide bounds for the minimum number of colors needed for such colorings for the Cartesian product of graphs along with exact results for generalized hypercubes. We also present general bounds for the direct, strong and lexicographic products.
The impact of noise estimation on dehazing
2020
International audience; Under haze or fog, the quality of the images is degraded due to the atmosphere, causing the details of the images to be difficult to identify by observers and computer vision systems. Such images contain noise, which is mainly due either to environment (extrinsic noise) or sensor (intrinsic noise). As the transmission of light coming from the scenes' objects is exponentially attenuated and comes quickly down to zero in presence of haze, the noise is greatly amplified at high haze densities and long distances. In order to investigate the importance of the accurate estimation and the removal of noise from hazy images, we used the CHIC (Color Hazy Image for Comparison) …
Effet anti-tumoral de l'acide docosahexaénoïque : implication des microARNs et du TNFalpha
2015
Docosahexaenoic acid (DHA) is an omega-3 polyunsaturated fatty acid with anti-inflammatory and anti-tumoral properties. The anti-tumor effect of DHA in colorectal cancer might be attributed to direct anti-proliferative action on cancer cells and to its ability to reduce inflammatory status involved in tumor growth. Tumor Necrosis Factor-alpha (TNFa) is an inflammatory cytokine with paradoxical effect in cancer biology. According to the cellular context, TNFa activates RIP1 kinase dependent signaling pathway leading to proliferation or cell death. Our aim was to evaluate the role of TNFa in anti-proliferative effect of DHA in colon cancer cells and to precise the molecular mechanisms regulat…
Isolated lung perfusion with chemotherapy in a pig model
2014
Introduction: The isolated lung perfusion (ILP) is an experimental technique which main objective is to deliver high dose of cytotoxic agent to the lung tissue without systemic exposure. The thesis took place in three stages: first stage, setting in vitro the chemotherapy the most efficient against colorectal cancer (CCR) cells in 30 min. Second stage, develop the ILP technique in a pig model. Third stage, lead a dose escalation study with chemotherapy by ILP.Methods: First stage, efficacy of various cytotoxic molecules against a panel of human CCR cell lines was tested in vitro after a 30-minute exposure. Second stage, pigs were treated with chemotherapy delivered by ILP during 30 minutes …
Fatty acid accumulation in the yeast Sporidiobolus salmonicor during batch production of gamma-decalactone
1997
International audience
Cropping system dynamics, climate variability, and seed losses among East African smallholder farmers: a retrospective survey.
2014
Abstract Climate variability directly affects traditional low input and rain-fed farming systems, but few studies have paid attention retrospectively to the cropping system’s ability to mitigate climate risk. This study analyzes the impacts of rainfall variability on farmers’ seed variety losses over time, considering changes in smallholder farming systems. The cropping system dynamics, in favoring maize at the expense of sorghum and pearl millet, have induced an increasing risk of seed loss during drought. Combining ecological anthropology and climatology, a retrospective survey asking farmers about the period 1961–2006 was carried out at three altitudinal levels (750, 950, and 1100 m) on …
Expression of Sorghum bicolor ammonium transporters upon colonization with arbuscular mycorrhizal fungi
2012
Expression of Sorghum bicolor ammonium transporters upon colonization with arbuscular mycorrhizal fungi
2012
Arbuscular mycorrhizal fungi (AMF) are important plant symbionts, trading mineral nutrients beyond the reach of roots, in particular ammonium, in exchange to their host’s photosynthetic products. Sorghum bicolor is one of the world's leading cereal crops, providing food, fibre and fuel across a range of environments and production systems. It has a particular ability to be productive even under strongly adverse conditions, tolerating much more severe drought than most other grain crops. As its genome has recently been sequenced, we have characterized all eight members of the ammonium transporter (AMT) family and studied their expression in different tissues of field-grown plants. While most…
Méthode de coloration pour l'observation et le comptage des endomycorhises à vésicules et arbuscules sur racines de maïs
2004
Cette méthode permet d'observer et de quantifier les Mycorhizes à Vésicules sur des racines de maïs sous loupe binoculaire (X 60)