Search results for "variant"

showing 10 items of 1267 documents

Prediction of Molecular Volume and Surface of Alkanes by Molecular Topology.

2003

Molecular volume and molecular surface are expressed as a function of topological degree in alkane graphs. This allows not only a straightforward approach to calculate such physicochemical magnitudes but also an interpretation of the role of the local vertex invariant (LOVI) or valence degree, delta, as well as the connectivity indices in the prediction of physicochemical properties. The interpretation is based on the concept of molecular accessibility (as introduced by Estrada, J. Phys. Chem. A 2002, 106, 9085) for which precise mathematical definitions are provided.

Vertex (graph theory)Surface (mathematics)Alkanechemistry.chemical_classificationValence (chemistry)Degree (graph theory)ChemistryGeometryGeneral ChemistryGeneral MedicineFunction (mathematics)Computer Science ApplicationsInterpretation (model theory)Computational Theory and MathematicsStatistical physicsMolecular topologyInvariant (mathematics)Information SystemsMathematicsChemInform
researchProduct

Fast Axial Scanning in 3D Imaging

2016

We establish the conditions for obtaining fast axial 3D microscopy with constant magnification, invariant resolution, and symmetrical displacement range. We demonstrate that liquid lenses permit the axial scanning free of mechanical movements and vibrations. This allows speeding-up the process and avoiding distortionsin the image of dynamic specimens. Article not available.

VibrationOpticsThree dimensional imagingChemistrybusiness.industryResolution (electron density)MagnificationInvariant (mathematics)business3d microscopyDisplacement (vector)Imaging and Applied Optics 2016
researchProduct

Augmented Reality of the Middle Ear Combining Otoendoscopy and Temporal Bone Computed Tomography

2018

International audience; HYPOTHESIS:Augmented reality (AR) may enhance otologic procedures by providing sub-millimetric accuracy and allowing the unification of information in a single screen.BACKGROUND:Several issues related to otologic procedures can be addressed through an AR system by providing sub-millimetric precision, supplying a global view of the middle ear cleft, and advantageously unifying the information in a single screen. The AR system is obtained by combining otoendoscopy with temporal bone computer tomography (CT).METHODS:Four human temporal bone specimens were explored by high-resolution CT-scan and dynamic otoendoscopy with video recordings. The initialization of the system…

Video RecordingOptical flowEar MiddleScale-invariant feature transformInitialization03 medical and health sciencesImaging Three-Dimensional0302 clinical medicine[INFO.INFO-IM]Computer Science [cs]/Medical ImagingHumansMedicineComputer vision[SDV.MHEP.OS]Life Sciences [q-bio]/Human health and pathology/Sensory Organs030223 otorhinolaryngologybusiness.industryTemporal BoneEndoscopyFrame rateSensory SystemsRefresh rateOtorhinolaryngologyFeature (computer vision)030220 oncology & carcinogenesisAugmented realityNeurology (clinical)Artificial intelligenceTomographyTomography X-Ray ComputedbusinessOtology & Neurotology
researchProduct

INTEGRATIVE APPROACH BETWEEN GENE VARIANTS, NEUROENDOCRINE EFFECTORS AND ANXIETY RESPONSE: A PILOT STUDY

2016

The aim of this study is to investigate the neurobiology of stress/emotionality, creating a multidisciplinary assessment model, which can help to provide psychological and physiological responses depending on the genetic background related to sport performances, social closeness and performance anxiety management in team sports. We enrolled 20 female volleyball players aged 13 ± 1 years old played in two different teams during a regional championship final. Saliva collection was carried out before and after the match. In order to evaluate the neuroendocrine effectors involved in stress and performance, we analyzed cortisol and progesterone levels through Elisa standard kit as well as HSP70 …

Volleyball players Dat1 and BDNF gene variants oxidative stress cortisol
researchProduct

iGEMS : an integrated model for identification of alternative exon usage events

2016

DNA microarrays and RNAseq are complementary methods for studying RNA molecules. Current computational methods to determine alternative exon usage (AEU) using such data require impractical visual inspection and still yield high false-positive rates. Integrated Gene and Exon Model of Splicing (iGEMS) adapts a gene-level residuals model with a gene size adjusted false discovery rate and exon-level analysis to circumvent these limitations. iGEMS was applied to two new DNA microarray datasets, including the high coverage Human Transcriptome Arrays 2.0 and performance was validated using RT-qPCR. First, AEU was studied in adipocytes treated with (n = 9) or without (n = 8) the anti-diabetes drug,…

WHITE ADIPOCYTESPHYSICAL-ACTIVITYDIFFERENTIATIONARRAY ANALYSISSPLICE VARIANTSRNA-SEQ3111 BiomedicineHUMAN TISSUESTRANSCRIPTOMEalternative exon usageMICROARRAYS3142 Public health care science environmental and occupational healthGENE-EXPRESSION
researchProduct

Chiral symmetry andπ-πscattering in the covariant spectator theory

2014

The π-π scattering amplitude calculated with a model for the quark-antiquark interaction in the framework of the Covariant Spectator Theory (CST) is shown to satisfy the Adler zero constraint imposed by chiral symmetry. The CST formalism is established in Minkowski space and our calculations are performed in momentum space. We prove that the axial-vector Ward-Takahashi identity is satisfied by our model. Then we show that, similarly to what happens within the Bethe-Salpeter formalism, application of the axial-vector Ward Takahashi identity to the CST π-π scattering amplitude allows us to sum the intermediate quark-quark interactions to all orders. Thus, the Adler self-consistency zero for π…

Ward–Takahashi identityPhysicsNuclear and High Energy PhysicsChiral symmetryBethe–Salpeter equation010308 nuclear & particles physicsScatteringHigh Energy Physics::LatticeNuclear TheoryHigh Energy Physics::PhenomenologyPosition and momentum space01 natural sciencesScattering amplitudeQuantum mechanics0103 physical sciencesMinkowski spaceCovariant transformation010306 general physicsPhysical Review D
researchProduct

On the classification of type D space–times

2002

We give a classification of the type D spacetimes based on the invariant differential properties of the Weyl principal structure. Our classification is established using tensorial invariants of the Weyl tensor and, consequently, besides its intrinsic nature, it is valid for the whole set of the type D metrics and it applies on both, vacuum and non-vacuum solutions. We consider the Cotton-zero type D metrics and we study the classes that are compatible with this condition. The subfamily of spacetimes with constant argument of the Weyl eigenvalue is analyzed in more detail by offering a canonical expression for the metric tensor and by giving a generalization of some results about the non-exi…

Weyl tensorPhysicsGeneral Relativity and Quantum Cosmologysymbols.namesakePure mathematicssymbolsFOS: Physical sciencesStatistical and Nonlinear PhysicsGeneral Relativity and Quantum Cosmology (gr-qc)Invariant (mathematics)General Relativity and Quantum CosmologyMathematical PhysicsEigenvalues and eigenvectorsJournal of Mathematical Physics
researchProduct

Writer identification for historical handwritten documents using a single feature extraction method

2020

International audience; With the growth of artificial intelligence techniques the problem of writer identification from historical documents has gained increased interest. It consists on knowing the identity of writers of these documents. This paper introduces our baseline system for writer identification, tested on a large dataset of latin historical manuscripts used in the ICDAR 2019 competition. The proposed system yielded the best results using Scale Invariant Feature Transform (SIFT) as a single feature extraction method, without any preprocessing stage. The system was compared against four teams who participated in the competition with different feature extraction methods: SRS-LBP, SI…

Writer identificationComputer sciencebusiness.industryFeature extractionhistorical documentsScale-invariant feature transform020207 software engineeringPattern recognition02 engineering and technologyartificial intelligenceConvolutional neural networkSupport vector machineIdentification (information)sift descriptors0202 electrical engineering electronic engineering information engineeringIdentity (object-oriented programming)Unsupervised learning020201 artificial intelligence & image processing[INFO]Computer Science [cs]Artificial intelligencebusiness
researchProduct

Modeling the Spatial Distribution of Xylella fastidiosa: A Nonstationary Approach with Dispersal Barriers

2022

Spatial species distribution models often assume isotropy and stationarity, implying that spatial dependence is direction-invariant and uniform throughout the study area. However, these assumptions are violated when dispersal barriers are present. Despite this, the issue of nonstationarity has been little explored in the context of plant health. The objective of this study was to evaluate the influence of barriers in the distribution of Xylella fastidiosa in the demarcated area in Alicante, Spain. Occurrence data from 2018 were analyzed through spatial Bayesian hierarchical models. The stationary model, illustrating a scenario without control interventions or geographical features, was com…

Xylella fastidiosaAlmond leaf scorchNon-stationary modelsIsotropySpecies distributionStochastic partial differential equationPlant ScienceContainmentBiologySpatial distributionbiology.organism_classificationDisease controlINLABiological dispersalU10 Mathematical and statistical methodsStatistical physicsXylella fastidiosaSpatial dependenceInvariant (mathematics)H20 Plant diseasesAgronomy and Crop ScienceBarriersEradication
researchProduct

Spatially variant dimensionality reduction for the visualization of multi/hyperspectral images

2011

International audience; In this paper, we introduce a new approach for color visu- alization of multi/hyperspectral images. Unlike traditional methods, we propose to operate a local analysis instead of considering that all the pixels are part of the same population. It takes a segmentation map as an input and then achieves a dimensionality reduction adaptively inside each class of pixels. Moreover, in order to avoid unappealing discon- tinuities between regions, we propose to make use of a set of distance transform maps to weigh the mapping applied to each pixel with regard to its relative location with classes' centroids. Results on two hyperspec- tral datasets illustrate the efficiency of…

[ INFO.INFO-TS ] Computer Science [cs]/Signal and Image ProcessingComputer sciencePopulation0211 other engineering and technologiesComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION02 engineering and technology[ SPI.SIGNAL ] Engineering Sciences [physics]/Signal and Image processing[INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing0202 electrical engineering electronic engineering information engineeringComputer visionSegmentationspectral imageseducationspatially variantvisualization021101 geological & geomatics engineeringdimensionality reductioneducation.field_of_studyPixelbusiness.industryDimensionality reductionHyperspectral imagingIndependent component analysisVisualizationComputer Science::Computer Vision and Pattern Recognition020201 artificial intelligence & image processingArtificial intelligencebusinessDistance transform[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing
researchProduct