181 research outputs found
Ecosystem Monitoring and Port Surveillance Systems
International audienceIn this project, we should build up a novel system able to perform a sustainable and long term monitoring coastal marine ecosystems and enhance port surveillance capability. The outcomes will be based on the analysis, classification and the fusion of a variety of heterogeneous data collected using different sensors (hydrophones, sonars, various camera types, etc). This manuscript introduces the identified approaches and the system structure. In addition, it focuses on developed techniques and concepts to deal with several problems related to our project. The new system will address the shortcomings of traditional approaches based on measuring environmental parameters which are expensive and fail to provide adequate large-scale monitoring. More efficient monitoring will also enable improved analysis of climate change, and provide knowledge informing the civil authority's economic relationship with its coastal marine ecosystems
Wireless Sensor Networks for Ecosystem Monitoring & Port Surveillance
International audienceProviding a wide variety of the most up - to - date innovations in sensor technology and sensor networks, our current project should achieve two major goals. The first goal covers various issues related to the public maritime transport safety and security, such as the coastal and port surveillance systems. While the second one w ill improve the capacity of public authorities to develop and implement smart environment policies by monitoring the shallow coastal water ecosystems. At this stage of our project, a surveillance platform has been already installed near the "MolĂšne Island" which is a small but the largest island of an archipelago of many islands located off the West coast of Brittany in North Western France. Our final objective is to add various sensors as well as to design, develop and implement new algorithms to extend th e capacity of the existing platform and reach the goals of our project. Finally, this manuscript introduces the identified approaches as well as t he second phase of the project which consists in analyzing living underwater micro - organisms (the population o f Marine Micro - Organisms, i.e. MMOs such as Phytoplankton and Zooplankton micro - zooplankton, but also heterotrophic bacterioplankton) in order to predict the health conditions of the macro - environment s . In addition, this communication discusses developed t echniques and concepts to deal with several practical problems related to our project. Some results are given and the whole system architecture is briefly described. This manuscript will also addresses the national benefit of such projects in the case of t hree different countries (Australia, France and KS
Contribution of automatic classification of sonar images for long term registration
This issue handles the ability of using segmentation results of sidescan sonar images for long term registration. This
study take a part of AUV (Autonomous Underwater Vehicle) navigation problems, particularly to correct the drift of
navigation sensors.
Principle of images formation with this type of engines and the main properties are first reminded. Some images are
shown, which allows us to understand difficulties of this type of data to realise AUV positioning. Then, we decide that
segmentation results of sidescan images provide us landscapes on which registration will be able. Segmentation is then explained. It is supervised type on five classes, rocks, ripples, sand, mud and shadow. Using Gabor
filters provides classifying parameters and classification is realised by the nearest neighbour. This is made step by step,
refining step by step the segmentation.
In order to know which landscapes may be extracted to enable the positioning, a statement is then realised on the
obtained results. The registration methodology is then quickly explained and several results are commented. This allows
us to realise a final conclusion on the ability to use results of segmentation of sonar images to make registration and to
give possibilities and limits of this type of positioning system.Cet article aborde la possibilitĂ© dâutiliser les rĂ©sultats de segmentation dâimages issues dâun sonar latĂ©ral pour
effectuer un recalage Ă long terme. Ce travail sâinscrit dans les problĂ©matiques liĂ©es Ă la navigation des AUV
(Autonomous Underwater Vehicle). Ceux-ci, navigant gĂ©nĂ©ralement Ă lâestime, subissent une dĂ©rive quâil est
nécessaire de réguliÚrement contrecarrer.
Le principe de formation des images Ă lâaide dâun tel engin est alors rappelĂ©, ainsi que ses propriĂ©tĂ©s
principales. Quelques exemples dâimages sont Ă©galement montrĂ©s, ce qui nous permet dâapprĂ©hender
les difficultĂ©s liĂ©es Ă lâutilisation de telles donnĂ©es pour effectuer le positionnement. Nous dĂ©cidons alors que
les résultats de segmentation des images sonar fourniront les amers sur lesquels on pourra se recaler.
La segmentation des images est alors expliquée. Elle est de type supervisé sur cinq classes, roches, rides,
sable, vase et ombre. Le filtrage par ondelettes de Gabor fournit les paramĂštres classifiants et la classification
est réalisée par le plus proche voisin. Celle-ci est alors effectuée pas à pas, en affinant peu à peu
la segmentation alors obtenue.
Un Ă©tat des lieux est ensuite rĂ©alisĂ© sur les rĂ©sultats obtenus, permettant de savoir quels amers peuvent ĂȘtre
extraits pour permettre le positionnement. La méthode de recalage est ensuite rapidement expliquée,
et plusieurs rĂ©sultats obtenus sont commentĂ©s en dĂ©tail. Cela permet alors dâeffectuer un bilan final sur la
possibilitĂ© dâutiliser les rĂ©sultats de segmentation dâimages sonar pour effectuer un recalage et indiquer les
possibilitĂ©s et les limitations de lâutilisation dâun tel systĂšme de positionnement
West Nile Virus in Morocco, 2003
West Nile virus (WNV) reemerged in Morocco in September 2003, causing an equine outbreak. A WNV strain isolated from a brain biopsy was completely sequenced. On the basis of phylogenetic analyses, Moroccan WNV strains isolated during the 1996 and 2003 outbreaks were closely related to other strains responsible for equine outbreaks in the western Mediterranean basin
GBA mutations are associated with Rapid eye movement sleep behavior disorder
Rapid eye movement sleep behavior disorder and GBA mutations are both
associated with Parkinsonâs disease. The GBA gene was sequenced in idiopathic
rapid eye movement sleep behavior disorder patients (n = 265), and compared
to controls (n = 2240). Rapid eye movement sleep behavior disorder questionnaire was performed in an independent Parkinsonâs disease cohort (n = 120).
GBA mutations carriers had an OR of 6.24 (10.2% in patients vs. 1.8% in controls, P < 0.0001) for rapid eye movement sleep behavior disorder, and among
Parkinsonâs disease patients, the OR for mutation carriers to have probable
rapid eye movement sleep behavior disorder was 3.13 (P = 0.039). These results
demonstrate that rapid eye movement sleep behavior disorder is associated with
GBA mutations, and that combining genetic and prodromal data may assist in
identifying individuals susceptible to Parkinsonâs disease
The dementia-associated APOE Δ4 allele is not associated with rapid eye movement sleep behavior disorder
The present study aimed to examine whether the APOE Δ4 allele, associated with dementia with Lewy bodies (DLB), and possibly with dementia in Parkinson's disease (PD), is also associated with idiopathic rapid eye movement sleep behavior disorder (RBD). Two single nucleotide polymorphisms, rs429358 and rs7412, were genotyped in RBD patients (n = 480) and in controls (n = 823). APOE Δ4 allele frequency was 0.14 among RBD patients and 0.13 among controls (OR = 1.11, 95% CI: 0.88-1.40, p = 0.41). APOE Δ4 allele frequencies were similar in those who converted to DLB (0.14) and those who converted to Parkinson's disease (0.12) or multiple system atrophy (0.14, p = 1.0). The APOE Δ4 allele is neither a risk factor for RBD nor it is associated with conversion from RBD to DLB or other synucleinopathies
Metronomic Four-Drug Regimen Has Anti-tumor Activity in Pediatric Low-Grade Glioma; The Results of a Phase II Clinical Trial
Background: Metronomic chemotherapy (MC) is defined as the frequent administration of chemotherapy at doses below the maximal tolerated dose and with no prolonged drug-free break. MC has shown its efficacy in adult tumor types such as breast and ovarian cancer and has to some extent been studied in pediatrics.Objective: To assess the anti-tumor activity and toxicity of a four-drug metronomic regimen in relapsing/refractory pediatric brain tumors (BT) with progression-free survival (PFS) after two cycles as primary endpoint.Methods: Patients â„4 to 25 years of age were included with progressing BT. Treatment consisted of an 8-week cycle of celecoxib, vinblastine, and cyclophosphamide alternating with methotrexate. Kepner and Chang two-steps model was used with 10 patients in the first stage. If stabilization was observed in â„2 patients, 8 additional patients were recruited. Assessment was according WHO criteria with central radiology review.Results: Twenty-nine patients (27 evaluable) were included in two groups: ependymoma (group 1, N = 8), and miscellaneous BT (group 2): 3 medulloblastoma (MB), 5 high grade glioma (HGG), 11 low grade glioma (LGG), 2 other BT. After first stage, recruitment for ependymoma was closed [one patient had stable disease (SD) for 4 months]. Cohort 2 was opened for second stage since 1 HGG and 3 LGG patients had SD after two cycles. Recruitment was limited to LGG for the second stage and 2 partial responses (PR), 6 SD and 2 progressive disease (PD) were observed after two cycles. Of these patients with LGG, median age was 10 years, nine patients received vinblastine previously. Median number of cycles was 6.8 (range: 1â12). Treatment was interrupted in five patients for grade 3/4 toxicity.Conclusion: This regimen is active in patients with LGG, even if patients had previously received vinblastine. Toxicity is acceptable.Trial Registration: This study was registered under clinicaltrials.gov â NCT01285817; EUDRACT nr: 2010-021792-81
SIGffRid: A tool to search for sigma factor binding sites in bacterial genomes using comparative approach and biologically driven statistics
<p>Abstract</p> <p>Background</p> <p>Many programs have been developed to identify transcription factor binding sites. However, most of them are not able to infer two-word motifs with variable spacer lengths. This case is encountered for RNA polymerase Sigma (<it>Ï</it>) Factor Binding Sites (SFBSs) usually composed of two boxes, called -35 and -10 in reference to the transcription initiation point. Our goal is to design an algorithm detecting SFBS by using combinational and statistical constraints deduced from biological observations.</p> <p>Results</p> <p>We describe a new approach to identify SFBSs by comparing two related bacterial genomes. The method, named SIGffRid (SIGma Factor binding sites Finder using R'MES to select Input Data), performs a simultaneous analysis of pairs of promoter regions of orthologous genes. SIGffRid uses a prior identification of over-represented patterns in whole genomes as selection criteria for potential -35 and -10 boxes. These patterns are then grouped using pairs of short seeds (of which one is possibly gapped), allowing a variable-length spacer between them. Next, the motifs are extended guided by statistical considerations, a feature that ensures a selection of motifs with statistically relevant properties. We applied our method to the pair of related bacterial genomes of <it>Streptomyces coelicolor </it>and <it>Streptomyces avermitilis</it>. Cross-check with the well-defined SFBSs of the SigR regulon in <it>S. coelicolor </it>is detailed, validating the algorithm. SFBSs for HrdB and BldN were also found; and the results suggested some new targets for these <it>Ï </it>factors. In addition, consensus motifs for BldD and new SFBSs binding sites were defined, overlapping previously proposed consensuses. Relevant tests were carried out also on bacteria with moderate GC content (i.e. <it>Escherichia coli</it>/<it>Salmonella typhimurium </it>and <it>Bacillus subtilis</it>/<it>Bacillus licheniformis </it>pairs). Motifs of house-keeping <it>Ï </it>factors were found as well as other SFBSs such as that of SigW in <it>Bacillus </it>strains.</p> <p>Conclusion</p> <p>We demonstrate that our approach combining statistical and biological criteria was successful to predict SFBSs. The method versatility autorizes the recognition of other kinds of two-box regulatory sites.</p
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