15 research outputs found
Stability calculations for the ytterbium-doped fiber laser passively mode-locked through nonlinear polarization rotation
We investigate theoretically a fiber laser passively mode-locked with
nonlinear polarization rotation. A unidirectional ring cavity is considered
with a polarizer placed between two sets of a halfwave plate and a quarterwave
plate. A master equation is derived and the stability of the continuous and
mode-locked solutions is studied. In particular, the effect of the orientation
of the four phase plates and of the polarizer on the mode-locking regime is
investigated
ETUDE EN IRM D'UNE SERIE DE 43 CAS DE CRANIOPHARYNGIOMES DE L'ENFANT (DES RADIODIAGNOSTIC ET IMAGERIE MEDICALE)
AIX-MARSEILLE2-BU MĂ©d/Odontol. (130552103) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF
Genetic parameters of caviar yield, color, size and firmness using parentage assignment in an octoploid fish species, the Siberian sturgeon Acipenser baerii
International audienceAquaculture is presently the only sustainable way of enhancing sturgeon caviar production as the use of wild stocks is banned throughout the world. Hence sustainable management and efficient genetic improvement of domesticated populations are major challenges for the development of farmed caviar. We estimated genetic parameters of caviar yields and quality traits (size, color and firmness) in the polyploid Siberian sturgeon A. baerii, one of the major sturgeon species farmed for meat and caviar worldwide. This study was performed in commercial breeding conditions, where two factorial mating plans were created to produce 77 families. Larvae were pooled at hatching and reared in common environment until the age of caviar production. We phenotyped 494 females, which were successfully assigned to their parents with microsatellite markers using a newly developed software, designed to manage genotypes with varying ploidy levels, up to 8 N. The genetic parameters were estimated using heteroscedastic multi-trait BLUP animal models. Heritability of body weight, ovary weight, caviar weight, caviar (egg) size, caviar yield, caviar firmness and caviar color were moderate to high (0.13 to 0.66) depending on the trait. Moderate negative genetic correlations were estimated between growth and caviar yields (â0.28 to â0.37) while genetic correlations between caviar (egg) size and caviar yield were more negative (â0.70 to â0.76). These results provide favorable grounds to improve the efficiency of farmed caviar production by selective breeding
Distal cerebral vasospasm treatment following aneurysmal subarachnoid hemorrhage using the Comaneci device: technical feasibility and single-center preliminary results
International audienceBackground Balloon-assisted mechanical angioplasty for cerebral vasospasm following aneurysmal subarachnoid hemorrhage (aSAH) has a number of limitations, including transient occlusion of the spastic blood vessel. Comaneci is an FDA-approved device for temporary coil embolization assistance which has recently also been approved for the treatment of distal symptomatic refractory vasospasm. We aimed to report the feasibility, efficacy and safety of our experience with Comaneci angioplasty for refractory distal vasospasm (up to the second segment of the cerebral arteries) following aSAH. Methods This is a retrospective analysis of a prospective series of 18 patients included between April 2019 and June 2021 with aSAH and symptomatic vasospasm refractory to medical therapy, who were treated using Comaneci-17-asssisted mechanical distal angioplasty. Immediate angiographic results, procedure-related complications, and clinical outcomes were assessed. Inter-rater reliability of the scores was determined using the intraclass correlation coefficient. Results Comaneci-assisted distal angioplasty was performed in 18 patients, corresponding to 31 target arteries. All distal anterior segments were easily accessible with the Comaneci-17 device. Vasospasm improvement after Comaneci mechanical angioplasty was seen in 22 distal arteries (71%) (weighted Cohenâs kappa (Îș w ) 0.73, 95% CI 0.69 to 0.93). Vasospasm recurrence occurred in three patients (16.67%) and delayed cerebral infarction in three patients (16.67%), with a mean±SD delay between onset of symptoms and imaging follow-up (MRI/CT) of 32.61±8.93 days (Îș w 0.98, 95% CI 0.88 to 1). Conclusion This initial experience suggests that distal mechanical angioplasty performed with the Comaneci-17 device for refractory vasospasm following aSAH seems to be safe, with good feasibility and efficacy
Maximizing the reliability of genomic selection by optimizing the calibration set of reference individuals: comparison of methods in two diverse groups of maize inbreds (Zea mays L.)
Chantier qualité GAGenomic selection refers to the use of genotypic information for predicting breeding values of selection candidates. A prediction formula is calibrated with the genotypes and phenotypes of reference individuals constituting the calibration set. The size and the composition of this set are essential parameters affecting the prediction reliabilities. The objective of this study was to maximize reliabilities by optimizing the calibration set. Different criteria based on the diversity or on the prediction error variance (PEV) derived from the realized additive relationship matrix-best linear unbiased predictions model (RA-BLUP) were used to select the reference individuals. For the latter, we considered the mean of the PEV of the contrasts between each selection candidate and the mean of the population (PEVmean) and the mean of the expected reliabilities of the same contrasts (CDmean). These criteria were tested with phenotypic data collected on two diversity panels of maize (Zea mays L.) genotyped with a 50k SNPs array. In the two panels, samples chosen based on CDmean gave higher reliabilities than random samples for various calibration set sizes. CDmean also appeared superior to PEVmean, which can be explained by the fact that it takes into account the reduction of variance due to the relatedness between individuals. Selected samples were close to optimality for a wide range of trait heritabilities, which suggests that the strategy presented here can efficiently sample subsets in panels of inbred lines. A script to optimize reference samples based on CDmean is available on request