Search results for "CEM"
showing 10 items of 3487 documents
Analysis of discrete and continuous distributions of ventilatory time constants from dynamic computed tomography.
2005
In this study, an algorithm was developed to measure the distribution of pulmonary time constants (TCs) from dynamic computed tomography (CT) data sets during a sudden airway pressure step up. Simulations with synthetic data were performed to test the methodology as well as the influence of experimental noise. Furthermore the algorithm was applied to in vivo data. In five pigs sudden changes in airway pressure were imposed during dynamic CT acquisition in healthy lungs and in a saline lavage ARDS model. The fractional gas content in the imaged slice (FGC) was calculated by density measurements for each CT image. Temporal variations of the FGC were analysed assuming a model with a continuous…
Interspecific aggression and character displacement in the damselfly Calopteryx splendens
2004
Problems in species recognition are thought to affect the evolution of secondary sexual characters mainly through avoidance of maladaptive hybridization. Another, but much less studied avenue for the evolution of sexual characters due to species recognition problems is through interspecific aggression. In the damselfly, Calopteryx splendens, males have pigmented wing spots as a sexual character. Large-spotted males resemble males of another species, Calopteryx virgo, causing potential problems in species recognition. In this study, we investigate whether there is character displacement in wing spot size and whether interspecific aggression could cause this pattern. We found first that wing …
Maintenance of male reaction to the congeneric song in the Hippolais warbler hybrid zone
1999
Both hybridization and competition may induce character shift on communication systems in hybrid zones, leading either to convergence or divergence. Melodious warblers Hippolais polyglotta and Icterine warblers H. icterina are interspecifically territorial and hybridize along a narrow contact zone. This spatial distribution is favoured by a reaction to the congeneric song. A character displacement, e.g. a decrease of the reaction, was expected within the hybrid zone because of reproduction costs lower than in allopatry. We investigated the pattern of variation of the interspecific reaction by comparing allopatric and sympatric populations. However, our data did not support the hypothesis ch…
L'impôt syndical et patronal
2015
International audience; Depuis 2011, les principaux syndicats de salariés et les organisations patronales doivent publier leurs comptes. Les premières publications montrent la difficulté de l’exercice mais surtout ils révèlent le poids prépondérant des subventions dans les ressources des organisations syndicales. Cette question est revenue au premier plan en 2013-2014, lors de la réforme de la formation professionnelle. Les partenaires sociaux et le gouvernement se sont mis d’accord pour créer, en leur faveur, un nouvel impôt assis sur les salaires. Ils ont affirmé que ce prélèvement mettra fin aux prélèvements sur diverses institutions de l’Etat social. Mais cette substitution est loin d’ê…
Superresolved digital in-line holographic microscopy for high-resolution lensless biological imaging.
2010
Digital in-line holographic microscopy (DIHM) is a modern approach capable of achieving micron-range lateral and depth resolutions in three-dimensional imaging. DIHM in combination with numerical imaging reconstruction uses an extremely simplified setup while retaining the advantages provided by holography with enhanced capabilities derived from algorithmic digital processing. We introduce superresolved DIHM incoming from time and angular multiplexing of the sample spatial frequency information and yielding in the generation of a synthetic aperture (SA). The SA expands the cutoff frequency of the imaging system, allowing submicron resolutions in both transversal and axial directions. The pr…
Surpassing digital holography limits by lensless object scanning holography.
2012
We present lensless object scanning holography (LOSH) as a fully lensless method, capable of improving image quality in reflective digital Fourier holography, by means of an extremely simplified experimental setup. LOSH is based on the recording and digital post-processing of a set of digital lensless holograms and results in a synthetic image with improved resolution, field of view (FOV), signal-to-noise ratio (SNR), and depth of field (DOF). The superresolution (SR) effect arises from the generation of a synthetic aperture (SA) based on the linear movement of the inspected object. The same scanning principle enlarges the object FOV. SNR enhancement is achieved by speckle suppression and c…
Preliminary results of a geomorphological and DInSAR characterization of a recently identified Deep-Seated Gravitational Slope Deformation in Sicily …
2019
The study is part of a larger project that involves the analysis of recently identified Deep-Seated Gravitational Slope Deformation (DSGSD) in Sicily which have been sub-divided according to the geological framework in light of the new geological data about the regional setting. Here are presented the first results of a multidisciplinary study of a DSGSD recently identify in Mount San Calogero area (Northern Sicily). The study was performed by means of different approaches including conventional methods (field surveys) and the Differential Interferometry Synthetic Aperture Radar (DInSAR) technique. The geological and geomorphological analyses were carried out to investigate slopes dynamic, …
Monitoring Water Surface and Level of a Reservoir Using Different Remote Sensing Approaches and Comparison with Dam Displacements Evaluated via GNSS
2018
Remote sensing allowed monitoring the reservoir water level by estimating its surface extension. Surface extension has been estimated using different approaches, employing both optical (Landsat 5 TM, Landsat 7 ETM+ SLC-Off, Landsat 8 OLI-TIRS and ASTER images) and Synthetic Aperture Radar (SAR) images (Cosmo SkyMed and TerraSAR-X). Images were characterized by different acquisition modes, geometric and spectral resolutions, allowing the evaluation of alternative and/or complementary techniques. For each kind of image, two techniques have been tested: The first based on an unsupervised classification and suitable to automate the process, the second based on visual matching with contour lines…
Source document verification in the Mucopolysaccharidosis Type I Registry
2011
Purpose The Mucopolysaccharidosis Type I (MPS I) Registry is an international observational database that tracks the natural history and the outcomes of patients with MPS I. The Registry was a regulatory requirement following the approval of laronidase enzyme replacement therapy for MPS I in 2003. All data are collected voluntarily after informed consent from the patient or family. Data are checked through queries, monthly reviews, and electronic audits to identify missing, inconsistent, or invalid data. This analysis sought to determine overall data accuracy in the Registry through source document verification (SDV). Methods Two phases of SDV were performed. In each phase, Registry data we…
Assessment of soil particle erodibility and sediment trapping using check dams in small semi-arid catchments
2017
Check dams can be used as a source of information for studies on sediment characteristics and soil particle erodibility. In this study, sediment yield and grain size distribution (GSD) were measured in twenty small catchments draining into a rock check dam in NW Iran for different runoffs during 2010–2011. Significant correlations were found between sediment yield and slope steepness, vegetation cover and soil erodibility factor (K) of the catchments. The erodibility of soil particles was determined using the comparison of GSD between sediment and original soil. Clay was the most erodible soil particle which showed 2.05 times more percentage in sediment than the original soil. The erodibili…