Poopćenje analitičkih izraza za pseudo -voigtovu funkciju koja se rabi u analizama difrakcijskih vrhova

Nous revisitons ici la théorie, utilisée en analyse des profils de raies de diffraction des rayons X et des neutrons, relative à la fonction de forme du pic dite de pseudo -Voigt (notée pV). Nous présentons une généralisation des expressions de la largeur intégrale et à mi-hauteur de la fonction pV, de la transformée de Fourier de cette fonction ainsi que du seuil du paramètre de mélange h. Nous incorporons nos résultats dans la procédure de fit, ce qui améliore les facteurs de précision.Razmatramo teoriju koja se primjenjuje u analizi linija difraktiranog rentgenskog zračenja i neutrona a odnosi se na tzv. pseudo-Voigtovu (skraćeno pV) funkciju za opis oblika vrha. Dajemo poopćenje analitičkog izraza za ukupnu širinu i širinu na pola visine vrha funkcije pV, Fourierovu transformaciju izraza, kao i prag parametra miješanja η. Primijenjujemo naš postupak za prilagodbu i postižemo poboljšanje točnosti

A method for performance diagnosis and evaluation of video trackers

Several measures for evaluating multi-target video trackers exist that generally aim at providing ‘end performance.’ End performance is important particularly for ranking and comparing trackers. However, for a deeper insight into trackers’ performance it would also be desirable to analyze key contributory factors (false positives, false negatives, ID changes) that (implicitly or explicitly) lead to the attainment of a certain end performance. Specifically, this paper proposes a new approach to enable a diagnosis of the performance of multi-target trackers as well as providing a means to determine the end performance to still enable their comparison in a video sequence. Diagnosis involves analyzing probability density functions of false positives, false negatives and ID changes of trackers in a sequence. End performance is obtained in terms of the extracted performance scores related to false positives, false negatives and ID changes. In the experiments, we used four state-of-the-art trackers on challenging real-world public datasets to show the effectiveness of the proposed approach

Evaluation of a Melanocortin-4 Receptor (MC4R) agonist (Setmelanotide) in MC4R deficiency

$\textbf{Objective:}$ Pro-opiomelanocortin (POMC)-derived peptides act on neurons expressing the Melanocortin 4 receptor (MC4R) to reduce body weight. Setmelanotide is a highly potent MC4R agonist that leads to weight loss in diet-induced obese animals and in obese individuals with complete POMC deficiency. While POMC deficiency is very rare, 1e5% of severely obese individuals harbor heterozygous mutations in MC4R. We sought to assess the efficacy of Setmelanotide in human MC4R deficiency. $\textbf{Methods:}$ We studied the effects of Setmelanotide on mutant MC4Rs in cells and the weight loss response to Setmelanotide administration in rodent studies and a human clinical trial. We annotated the functional status of 369 published MC4R variants. $\textbf{Results:}$ In cells, we showed that Setmelanotide is significantly more potent at MC4R than the endogenous ligand alpha-melanocyte stimulating hormone and can disproportionally rescue signaling by a subset of severely impaired MC4R mutants. Wild-type rodents appear more sensitive to Setmelanotide when compared to MC4R heterozygous deficient mice, while MC4R knockout mice fail to respond. In a 28-day Phase 1b clinical trial, Setmelanotide led to weight loss in obese MC4R variant carriers. Patients with POMC defects upstream of MC4R show significantly more weight loss with Setmelanotide than MC4R deficient patients or obese controls. $\textbf{Conclusions:}$ Setmelanotide led to weight loss in obese people with MC4R deficiency; however, further studies are justified to establish whether Setmelanotide can elicit clinically meaningful weight loss in a subset of the MC4R deficient obese population.This work was supported by the Wellcome Trust (I.S.F.), the National Institute for Health Research Cambridge Biomedical Research Centre (S.O’R., I.S.F.), the Bernard Wolfe Health Neuroscience Fund (I.S.F.), the European Research Council (I.S.F.), and the Swiss National Science Foundation (PBLAP3-145870, P3SMP3-155318, PZ00P3-167826 to T.-H.C.). Funds were also obtained from the Clinical Research Programs on Obesity (Assistance Publique-Hôpitaux de Paris, and the Direction of Clinical Research (CRC) (PHRC 02076 to K.C.), as well as the Institut Benjamin Delessert and the Fondation pour la Recherche Médicale and the National Agency of Research (program “Investissements d’Avenir” with the reference ANR-10-IAHU-05). The clinical trial was supported by Rhythm Pharmaceuticals

Étude de la variation du paramètre de réseau de solutions solides Cu-Ni par diffraction des rayons X

Des solutions solides Cu-Ni avec différentes concentrations de Ni sont élaborées puis analysées aux rayons X pour déterminer leur paramètre de réseau. On utilise la chambre Debye-Scherrer et la méthode d'extrapolation de Nelson et Riley. Les résultats montrent que la variation de ce paramètre en fonction de la concentration de Ni n'obéit pas à la loi de Végard et met en évidence l'existence d'une transition de phase pour une concentration massique de 69% Ni

Microstructure and residual stresses in Ti-6Al-4V alloy pulsed and unpulsed TIG welds

International audienceIncreasing the pulse frequency in pulsed Tungsten Inert Gas arc welding refines the prior-␤ grain size in the fusion zone of Ti-6Al-4V alloy compared to unpulsed process. The microhardness increases in the fusion zones (FZs) obtained with pulsed welding process with respect to their microstructural evolution. The increase of the pulse frequency contributes to the formation of a significant amount of residual ␤ phase in the FZ which is accompanied by a decrease of its microhardness. The tensile residual stresses (RSs) level in the pulsed process is lower than the one of the unpulsed one. The tensile RSs induced by both welding processes in the heat affected zone (HAZ) are found to decrease when increasing the pulse frequency. In the FZ, the transversal RSs are of compressive type for both processes whereas the longitudinal ones change from tensile to compressive type when increasing the pulse frequency