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After tetralogy of Fallot (TOF) repair, pulmonary regurgitation and right ventricular function must be monitored. Conventional (2D) cardiac magnetic resonance (CMR) is currently the clinical reference method for measuring pulmonary regurgitation. However, 4DFlow CMR has been reported to provide a more comprehensive flow analysis than 2D CMR. We aimed to compare 4DFlow CMR to 2D CMR for assessing pulmonary regurgitation and flow, as well as aortic flow, in children and adults after surgical repair of TOF.Retrospective analysis of patients with repaired TOF admitted for cardiac MRI with 4DFlow acquisition from 2016 to 2018. Linear regression was used to assess correlations and Bland-Altman analyses were performed.The 60 included patients had a mean age of 18.2 ± 10.4 years (range, 2-54 years). Significant correlations between the two techniques were found for pulmonary regurgitant fraction (R [2] = 0.6642, p 0.0001), net pulmonary flow (R [2] = 0.6782, p 0.0001), forward pulmonary flow (R [2] = 0.6185, p 0.0001), backward pulmonary flow (R [2] = 0.8192, p 0.0001), and aortic valve flow (R [2] = 0.6494, p 0.0001). The Bland-Altman analysis showed no significant bias, narrow limits of agreement, and few scattered points. The correlation between pulmonary and aortic flow was better with 4DFlow CMR than with 2D CMR (R [2] = 0.8564, p 0.0001 versus R [2] = 0.4393, p 0,0001, respectively). Interobserver reliability was good.These results establish the feasibility and reliability of 4DFlow CMR for assessing pulmonary flow in a large paediatric and adult population with repaired TOF. 4DFlow CMR may be more reliable than 2D MRI for pulmonary flow assessment after TOF repair.

Undoped ZnO and Al-doped ZnO (AZO) were synthesized by sol-gel method and deposited by spin coating. Zinc acetate dehydrate was used as precursor, while ethanolamine and ethanol were used as stabilizer and solvent, respectively, and aluminum nitrate nonahydrate was used as dopant. A comparative study of undoped ZnO and Al-doped ZnO (AZO) deposited by spin-coating at 0.75M was carried out. In this study optical, morphological, structural properties and crystallinity were investigated.

Background After tetralogy of Fallot (TOF) repair, pulmonary regurgitation and right ventricular function must be monitored. Conventional (2D) cardiac magnetic resonance (CMR) is currently the clinical reference method for measuring pulmonary regurgitation. However, 4D CMR has been reported to provide a more comprehensive flow analysis than 2D CMR. We aimed to compare 4D CMR to 2D CMR for assessing pulmonary regurgitation and flow, as well as aortic flow, in children and adults after surgical repair of TOF. Methods Retrospective analysis of patients with repaired TOF admitted for cardiac MRI with 4D flow acquisition from 2016 to 2018. Linear regression was used to assess correlations and Bland-Altman analyses were performed. Results The 60 included patients had a mean age of 18.2 ± 10.4 years (range, 2–54 years). Significant correlations between the two techniques were found for pulmonary regurgitant fraction (R2 = 0.6642, P Conclusion These results establish the feasibility and reliability of 4D CMR for assessing pulmonary flow in a large paediatric and adult population with repaired TOF. 4D CMR may be more reliable than 2D MRI for pulmonary flow assessment after TOF repair.

Machining defects as rebuilt material and dislodgement were often induced by cutting of difficult to machining AISI 304 stainless steel. Their density increases with a decreasing of cutting speed. The effect of these defects on surface topography and residual stress was evaluated by roughness and X-ray diffraction measurements coupled with numerical simulation. The role of the rebuilt material on the distribution of fatigue crack nucleation sites was investigated by scanning electron microscope examination of post fatigue samples loaded at different imposed strain amplitudes. The association of machining defects and fatigue crack nucleation sites was attributed to the contribution of additional tensile residual stresses induced by rebuilt material rather than local stress concentration. Moreover, the fatigue crack coalescence is promoted by increasing the rebuilt material density. When the machining defect density increases from 5 to 60 particles/mm2, the fatigue life decreases from -22% to -65% with respect to the electropolished surface. © 2014 Wiley Publishing Ltd.

ZnO:Ni thin films with Ni content of 0, 3, 5 and 7% were deposited onto ITO/glass substrates using the spin coating method. The deposited films were characterized for their structural, photoluminescence and electrical properties by respectively X ray diffraction (XRD), Raman spectroscopy, photoluminescence spectroscopy (PL) and the four points probe techniques. XRD patterns showed that the deposited films were polycrystalline with a hexagonal wurtzite structure. The absence of the Ni related diffraction peaks reflected the substitution of Zn atoms by Ni atoms in the ZnO lattice. The variation of both lattice parameters and crystallite size, as a function of Ni content, indicated that the Ni doping enhance the structural properties of the deposited films. In Raman spectra, the band at 667.9 cm−1 appeared for doped samples, was attributed to the Zn sites occupied by Ni atoms in the ZnO lattice. In PL spectra, the decrease of the UV band emission intensity, as a function of Ni content, was attributed to Ni ions doping. The concentration of deep level defect such as Zni,VZn and VO, decreased as a function of the Ni content. The electrical resistivity increase correlated with the increase of the of Ni3+-related impurity concentration which behaves as a source of free electrons for n-type conduction.

Background 4D flow cardiovascular magnetic resonance (4D Flow CMR) enable time-varying and multidirectional comprehensive retrospective flow quantification in patients after repaired tetralogy of Fallot (TOF). This imaging modality must, however, prove its relevance compared to conventional CMR. Methods 4D flow and 2D flow MRI were acquired using a clinical 1.5T MRI scanner (GE; GE Healthcare, Milwaukee, WI, USA). The 4D flow data were acquired in 18 patients after repair of TOF and in 5 healthy controls during free breathing using retrospectively ECG-gated and navigator-gated three-dimensional, three-directional phase contrast MRI (spatial resolution ∼ 1.4 mm, temporal resolution = 33 ms). Data analysis included the evaluation of haemodynamics in the aorta, the pulmonary trunk (TP), quantitative measurements of flow velocity, right ventricular volumes both by conventional 2D CMR and 4D Flow. Results Eighteen patients with TOF underwent 2D CMR and 4D Flow CMR (mean age 31 ± 13 years, mean size 168 ± 13 cm, mean weight 56.2 ± 13.4 kg). Among them 12 patients had complete evaluation including flow and ventricular volumes. The mean systolic ejection volume was 109 ± 44 mL; the mean right ventricle systolic function was 55 ± 12%. The mean end-diastolic right ventricle volume was respectively 185 ± 66 mL by 2D CMR, and 200 ± 68 mL using 4D Flow. The mean pulmonary regurgitation fraction was respectively 39 ± 18% by 2D CMR, and 32 ± 18% using 4D Flow. Pulmonary regurgitation fraction was almost interchangeable according to the Pearson's coefficient (r2 = 0.9, P Conclusions Based on our experience, 4D Flow imaging can be clinically helpful especially in TOF, compared to 2D CMR. Despite some biases, our results shows good accuracy compared to conventional 2D CMR. Further studies are needed to validate our first conclusions.

Resume Le zolpidem est une imidazopyridine possedant des proprietes sedatives et hypnotiques. Les auteurs rapportent deux cas de dependance au zolpidem a haute dose et les comparent aux autres cas decrits dans la litterature. Les deux patients sont des toxicomanes connus avant la premiere prise de zolpidem. La surconsommation et la dependance au produit sont rapides, jusqu’aux doses de 240 mg et 400 mg par jour, sans effet sedatif, a la recherche d’une anxiolyse et d’un effet stimulant. Le sevrage est caracterise par une anxiete majeure, il est marque chez l’un par une crise convulsive generalisee et chez l’autre par une bouffee delirante aigue. Une recente hypothese pharmacologique est proposee. La revue de la litterature permet de conclure que 50 % des cas de dependance au zolpidem sont retrouves chez des patients toxicomanes. Les auteurs suggerent que ces patients sont des sujets a risque de dependance au zolpidem.

International audience; In this study, a numerical approach has been developed to predict the near surface residual stresses and plastic strain resulting from turning in orthogonal cutting configuration. This approach is based on the Arbitrary Lagrangian-Eulerian (ALE) formulation using the commercial finite element code Abaqus-Explicit. The coefficients of the used material behavior law and friction model required for the simulation are identified experimentally in this study. The simulated results are validated by experiments carried out on AISI 316L stainless steel. Using this method, the effect of the depth of cut (Doc) and the cutting speed (Vc) on the surface properties has been established. The simulated residual stress gradient resulting from machining has been experimentally validated by X-ray diffraction measurements. The simulated plastic strain gradient has been validated by an experimental microhardness-strain relationship established in this study.

Les lymphomes mediastinaux representent un groupe de maladies heterogenes resultant de la proliferation maligne de cellules lymphoides matures a differents stades de differenciation. Cette proliferation peut se faire aux depends d’un organe ganglionnaire ou extra-ganglionnaire. Les manifestations thoraciques des lymphomes malins sont frequentes et tres variees. Elles sont habituellement d’apparitions secondaires rarement revelatrices. Il s’agit d’une etude retrospective portant sur les aspects cliniques, radiologiques et histologiques observes chez 19 patients hospitalises durant 7 ans de 2006 a 2013. L’effectif comprenait 8 femmes et 11 hommes avec un âge moyen de 32 ans. Les circonstances de decouvertes etaient des signes respiratoires chez 12 patients (toux dans 12 cas, dyspnee dans 7 cas, douleur thoracique dans 11 cas, syndrome cave superieure dans 3 cas), une alteration de l’etat general etaient observee chez 3 patients, des adenopathies peripheriques observees chez 4 patients, aucune decouverte n’a ete fortuite. La radiographie thoracique retrouvait un elargissement du mediastin chez 17 patients, pleuropneumopathie chez 1 patient et une condensation parenchymateuse dans 1 cas. Le diagnostic histologique etait porte par la biopsie trans-thoracique scannoguidee dans 11 cas, biopsie ganglionnaire peripherique dans 6 cas, biopsie chirurgicale dans 1 cas, biopsie pleurale dans 1 cas. Les signes biologiques inflammatoires etaient presents dans 47 % des cas. Le stade II de la classification Ann-Arbor etait present dans 68 % des cas, stade IV dans 15 % des cas, stade III dans 10 % des cas, stade I dans 5 % des cas.

The static response of capacitive pressure sensors with a thin rectangular or square diaphragm is studied, assuming small deflections. Lagrange's equation is solved from the virtual displacement theorem and an approximated polynomial solution. It is shown that response can be expressed under a normalized form dependent only on the value of the diaphragm dimension ratio. For a given silicon surface, square sensors exhibit the highest sensitivity whereas rectangular sensors have a more linear behaviour. Finally, the proposed formulation equally allows easy and rapid determination of the four geometric parameters defining this type of sensor Etude de la reponse en regime statique du capteur, dans l'hypothese des deformations faibles