Parametric models for facial features segmentation

In this paper, we are dealing with the problem of facial features segmentation (mouth, eyes and eyebrows). A specific parametric model is defined for each feature, each model being able to take into account all the possible deformations. In order to initialize each model, some characteristic points are extracted on each image to be processed (for example, the corners of the eyes, mouth and eyebrows). In order to fit the model with the contours to be extracted, a gradient flow (of luminance or chrominance ) through the estimated contour is maximized because at each point of the searched contour, the gradient (of luminance or chrominance) is normal. The advantage of the definition of a model associated to each feature is to be able to introduce a regularisation constraint. However, the chosen models are flexible enough in order to produce realistic contours for the mouth, the eyes and eyebrows. This facial features segmentation is the first step of a set of multi-media applications.Dans cet article, nous nous intéressons à l’extraction automatique des contours des traits permanents du visage à savoir : les yeux, les sourcils et les lèvres. Pour chacun des traits considérés, un modèle paramétrique spécifique capable de rendre compte de toutes les déformations possibles est défini. Lors de la phase d’initialisation, des points caractéristiques du visage sont extraits (coins des yeux et de la bouche par exemple) et servent de points d’ancrage initiaux pour chacun des modèles. Dans la phase d’évolution, chaque modèle est déformé afin de coïncider au mieux avec les contours des traits présents sur le visage analysé. Cette déformation se fait par maximisation d’un flux de gradient (de luminance et/ou de chrominance) le long des contours définis par chaque courbe du modèle. La définition de modèles permet d’introduire naturellement une contrainte de régularisation sur les contours recherchés. Néanmoins, les modèles choisis restent suffisamment flexibles pour permettre une extraction réaliste des contours des yeux, des sourcils et de la bouche. L’extraction précise des contours des principaux traits du visage constitue la première étape d’un ensemble d’applications multimédia

Extraction des traits caractéristiques du visage à l'aide de modèles paramétriques adaptés

- Dans cet article, nous nous intéressons à l'extraction automatique des contours des traits permanents du visage à savoir : les yeux, les sourcils et les lèvres. Pour chacun des traits considérés, un modèle paramétrique spécifique capable de rendre compte de toutes les déformations possibles est défini. Lors de la phase d'initialisation, des points caractéristiques du visage sont extraits (coins des yeux et de la bouche par exemple) et servent de points d'ancrage initiaux pour chacun des modèles. Dans la phase d'évolution, chaque modèle est déformé afin de plaquer au mieux sur les contours des traits présents dans le visage analysé. Cette déformation se fait par maximisation d'un flux de gradient (de luminance et/ou de chrominance) le long des contours définis par chaque courbe du modèle. La définition de modèles permet d'introduire naturellement une contrainte de régularisation sur les contours recherchés. Mais, les modèles choisis restent suffisamment flexibles pour permettre une extraction réaliste des contours des yeux, des sourcils et de la bouche. L'extraction précise des contours des principaux traits du visage constitue la première étape d'un système de reconnaissance des dynamiques émotionnelles

Oxaliplatin use in pressurized intraperitoneal aerosol chemotherapy (PIPAC) is safe and effective: A multicenter study.

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a new drug delivery method used in patients with peritoneal cancer (PC) of primary or secondary origin. Intraperitoneal use of oxaliplatin raises concerns about toxicity, especially abdominal pain. The objective of this study was to assess the tolerance of PIPAC with oxaliplatin (PIPAC-Ox) in a large cohort of patients and to identify the risk factors for high grade toxicity, discontinuation of treatment and impaired survival. This retrospective cohort study included all consecutive patients treated with PIPAC-Ox (92 mg/m <sup>2</sup> ) in five centers specialized in the treatment of PC. The procedure was repeated every 6 weeks. Outcomes of interest were Common Terminology Criteria for Adverse Events (CTCAE), symptoms and survival (Kaplan-Meier). Univariate risk factors were included in a multinominal regression model to control for bias. Overall, 251 PIPAC-Ox treatments were performed in 101 patients (45 female) having unresectable PC of various origins: 66 colorectal, 15 gastric, 5 ovarian, 3 mesothelioma, 2 pseudomyxoma, 10 other malignancies (biliary, pancreatic, endocrine) respectively. The median PCI was 19 (IQR: 10-28). Postoperative abdominal pain was present in 23 patients. Out of the 9 patients with grade 3 abdominal pain, only 3 needed a change of PIPAC drug. CTCAE 4.0 toxicity grade 4 or higher was encountered in 16(15.9%) patients. The patients had a mean of 2.5 procedures/patient (SD = 1.5). 50 subjects presented with symptom improvement. Oxaliplatin-based PIPAC appears to be a safe treatment that offers good symptom control and promising survival for patients with advanced peritoneal disease

An exploratory study about contamination of pens of finishing pigs by ubiquitous Salmonella

Salmonella is one of the most common food-borne pathogens transmitted to humans and human salmonellosis is primarily caused by contaminated food. Porcine products have been identified as important food vehicles in outbreaks of salmonellosis (I, 2, 3). In France, the majority of Salmonella infected pig herds are sub-clinically infected. S. Choleraesuis does not occur and only ubiquitous serotypes are isolated (4). Sub-clinically infection is characterized by intermittent shedding of small numbers of Salmonella. In these sub-clinically infected pig herds, an infectioncontamination-infection cycle is maintained with mainly an endemic house flora of Salmonella enterica (5). When contaminated batches from these farms are processed on the slaughter line, slaughtering practices contribute to Salmonella dissemination and carcass contamination. Within batches, there is a strong correlation between the proportion of animals with Salmonella spp. in their feces and the proportion of contaminated carcasses at the end of the line (6, 7). As a result of subclinical Salmonella infection in pig herds, Salmonella contamination of pork carcasses constitutes a threat to human health. The influence of a wide range of factors on subclinical Salmonella contamination of pig farms is not well known. A good understanding of risk factors for Salmonella contamination of pig herds is an essential stake in order to avoid Salmonella spread within herds and between herds and slaughterhouses. Thus, the aim of this study was to investigate potential risk factors for the presence of ubiquitous Salmonella in the finishing sheds of farrow-to-finish farms in France

High genetic diversity at the extreme range edge: nucleotide variation at nuclear loci in Scots pine (Pinus sylvestris L.) in Scotland

Nucleotide polymorphism at 12 nuclear loci was studied in Scots pine populations across an environmental gradient in Scotland, to evaluate the impacts of demographic history and selection on genetic diversity. At eight loci, diversity patterns were compared between Scottish and continental European populations. At these loci, a similar level of diversity (θsil=~0.01) was found in Scottish vs mainland European populations, contrary to expectations for recent colonization, however, less rapid decay of linkage disequilibrium was observed in the former (ρ=0.0086±0.0009, ρ=0.0245±0.0022, respectively). Scottish populations also showed a deficit of rare nucleotide variants (multi-locus Tajima's D=0.316 vs D=−0.379) and differed significantly from mainland populations in allelic frequency and/or haplotype structure at several loci. Within Scotland, western populations showed slightly reduced nucleotide diversity (πtot=0.0068) compared with those from the south and east (0.0079 and 0.0083, respectively) and about three times higher recombination to diversity ratio (ρ/θ=0.71 vs 0.15 and 0.18, respectively). By comparison with results from coalescent simulations, the observed allelic frequency spectrum in the western populations was compatible with a relatively recent bottleneck (0.00175 × 4Ne generations) that reduced the population to about 2% of the present size. However, heterogeneity in the allelic frequency distribution among geographical regions in Scotland suggests that subsequent admixture of populations with different demographic histories may also have played a role

M19 Modulates Skeletal Muscle Differentiation and Insulin Secretion in Pancreatic β-Cells through Modulation of Respiratory Chain Activity

Mitochondrial dysfunction due to nuclear or mitochondrial DNA alterations contributes to multiple diseases such as metabolic myopathies, neurodegenerative disorders, diabetes and cancer. Nevertheless, to date, only half of the estimated 1,500 mitochondrial proteins has been identified, and the function of most of these proteins remains to be determined. Here, we characterize the function of M19, a novel mitochondrial nucleoid protein, in muscle and pancreatic β-cells. We have identified a 13-long amino acid sequence located at the N-terminus of M19 that targets the protein to mitochondria. Furthermore, using RNA interference and over-expression strategies, we demonstrate that M19 modulates mitochondrial oxygen consumption and ATP production, and could therefore regulate the respiratory chain activity. In an effort to determine whether M19 could play a role in the regulation of various cell activities, we show that this nucleoid protein, probably through its modulation of mitochondrial ATP production, acts on late muscle differentiation in myogenic C2C12 cells, and plays a permissive role on insulin secretion under basal glucose conditions in INS-1 pancreatic β-cells. Our results are therefore establishing a functional link between a mitochondrial nucleoid protein and the modulation of respiratory chain activities leading to the regulation of major cellular processes such as myogenesis and insulin secretion

In Vitro vs In Silico Detected SNPs for the Development of a Genotyping Array: What Can We Learn from a Non-Model Species?

Background: There is considerable interest in the high-throughput discovery and genotyping of single nucleotide polymorphisms (SNPs) to accelerate genetic mapping and enable association studies. This study provides an assessment of EST-derived and resequencing-derived SNP quality in maritime pine (Pinus pinaster Ait.), a conifer characterized by a huge genome size (~23.8 Gb/C). [br/] Methodology/Principal Findings: A 384-SNPs GoldenGate genotyping array was built from i/ 184 SNPs originally detected in a set of 40 re-sequenced candidate genes (in vitro SNPs), chosen on the basis of functionality scores, presence of neighboring polymorphisms, minor allele frequencies and linkage disequilibrium and ii/ 200 SNPs screened from ESTs (in silico SNPs) selected based on the number of ESTs used for SNP detection, the SNP minor allele frequency and the quality of SNP flanking sequences. The global success rate of the assay was 66.9%, and a conversion rate (considering only polymorphic SNPs) of 51% was achieved. In vitro SNPs showed significantly higher genotyping-success and conversion rates than in silico SNPs (+11.5% and +18.5%, respectively). The reproducibility was 100%, and the genotyping error rate very low (0.54%, dropping down to 0.06% when removing four SNPs showing elevated error rates). [br/] Conclusions/Significance: This study demonstrates that ESTs provide a resource for SNP identification in non-model species, which do not require any additional bench work and little bio-informatics analysis. However, the time and cost benefits of in silico SNPs are counterbalanced by a lower conversion rate than in vitro SNPs. This drawback is acceptable for population-based experiments, but could be dramatic in experiments involving samples from narrow genetic backgrounds. In addition, we showed that both the visual inspection of genotyping clusters and the estimation of a per SNP error rate should help identify markers that are not suitable to the GoldenGate technology in species characterized by a large and complex genome

Structural decoding of netrin-4 reveals a regulatory function towards mature basement membranes

Netrins, a family of laminin-related molecules, have been proposed to act as guidance cues either during nervous system development or the establishment of the vascular system. This was clearly demonstrated for netrin-1 via its interaction with the receptors DCC and UNC5s. However, mainly based on shared homologies with netrin-1, netrin-4 was also proposed to play a role in neuronal outgrowth and developmental/pathological angiogenesis via interac- tions with netrin-1 receptors. Here, we present the high-resolution structure of netrin-4, which shows unique features in comparison with netrin-1, and show that it does not bind directly to any of the known netrin-1 receptors. We show that netrin-4 disrupts laminin networks and basement membranes (BMs) through high-affinity binding to the laminin g1 chain. We hypothesize that this laminin-related function is essential for the previously described effects on axon growth promotion and angiogenesis. Our study unveils netrin-4 as a non-enzymatic extracellular matrix protein actively disrupting pre-existing BMs

Uniform Selection as a Primary Force Reducing Population Genetic Differentiation of Cavitation Resistance across a Species Range

Background: Cavitation resistance to water stress-induced embolism determines plant survival during drought. This adaptive trait has been described as highly variable in a wide range of tree species, but little is known about the extent of genetic and phenotypic variability within species. This information is essential to our understanding of the evolutionary forces that have shaped this trait, and for evaluation of its inclusion in breeding programs. Methodology: We assessed cavitation resistance (P 50), growth and carbon isotope composition in six Pinus pinaster populations in a provenance and progeny trial. We estimated the heritability of cavitation resistance and compared the distribution of neutral markers (FST) and quantitative genetic differentiation (QST), for retrospective identification of the evolutionary forces acting on these traits. Results/Discussion: In contrast to growth and carbon isotope composition, no population differentiation was found for cavitation resistance. Heritability was higher than for the other traits, with a low additive genetic variance (h 2 ns = 0.4360.18, CVA = 4.4%). QST was significantly lower than FST, indicating uniform selection for P50, rather than genetic drift. Putativ