Vibrational Properties of Quasi-periodic beam structure

Quasi-periodic structures have been widely studied for its atom dynamics, Photonic, magnetic and electronic wave propagation(Ashraff and Stinchcombe (1989), Vekilov et al. (1999), Szallas and Jagannathan (2008)). These structures exhibit frequency ranges in which no propagative wave exist(Bayindir et al. (2001) and Engel et al. (2007)). Band gap can lead to interesting applications in various domain (Florescu et al. (2009)). The recent progress in the additive manufacturing open new possibilities for using quasi-periodic structures by allowing the printing of complex meta-materials, in a consistent manner. Additive manufactured meta material can be designed to exhibit unusual macroscopic behavior due to their internal structure as in (Bückmann et al. (2012) and Claeys et al. (2014)). Therefore the possibility of creating meta materials having the same properties than the quasi periodic atomic structures can be highly interesting and allow to get rid of unwanted complex behaviors (Engel et al. (2007)). Such meta material could create band gap in their virbational mechanical response while being isotropic.  The mechanical and vibrational properties of quasi-periodic and of amorphous structures are related to complex mathematical problems due to the impossibility of periodic simplifications. Therefore, in order to solve these problems, big size matrix problems have to be dealed with. In this paper a beam structure based on a octohedric quasi-periodic Pensore lattice approximant is studied. The octohedric Penrose tilling is chosen for his ability to create a periodic approximant to the quasi periodic tilling thus allowing the use of periodic boundary conditions as suggested in (Duneau (1989)).It has been shown in Sørensen et al. (1991) that, for ferromagnetic properties, the approximant with periodic boundary conditions closely mimic the in finite lattice properties. Numerical methods for the vibrational study of big systems have been applied from the atomic vibration domain up to finite elements modelization. Kernel Polynomial Method (KPM) is used herein to calculate the Vibrational Density Of States (VDOS) and the Dynamical Structure Factor (DSF) without exact diagonalization of the dynamical matrix. The KPM method is detailled by Lin et al. (2016) and was adapted to the study of to the vibrational properties of large-size systems by Beltukov et al. (2016b). These methods allow better understanding of vibrational response of quasi-periodic structures

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Nous avons tous nos logiciels ou autres outils favoris sans lesquels nous aurions désormais bien du mal à travailler. Des traducteurs présentent ci-dessous l’un de leurs outils préférés. Certains sont très connus, d’autres moins. Il serait étonnant que vous ne trouviez pas dans ces pages de quoi vous faciliter la vie ! Babylon Babylon n’est pas un logiciel d’aide à la traduction tel que nous les connaissons (OmegaT, Trados, etc.). Babylon est tout simplement un logiciel propriétaire qui nous ..

Management of diabetic macular edema with visual impairment in real-life practice in France: findings from the cross-sectional BOREAL DME study

Purpose: Diabetic macular edema (DME) is the leading cause of visual impairment (VI) in patients with diabetes. With the introduction of anti-vascular endothelial growth factor (anti-VEGF) agents, management of DME has evolved. The aim of this study was to identify the routine practice for the management of patients with VI due to DME (best-corrected visual acuity [BCVA] ≤ 20/40) in France in 2014. Methods: The cross-sectional, observational BOREAL DME study was conducted in a real-life practice in France on request of health authority. The study included patients with Type 1 or 2 diabetes aged ≥ 18 years who had a reduction in BCVA due to DME ( ≤ 20/40) irrespective of treatment prescribed at inclusion (including monitoring alone). The following medical data were collected from patients’ medical files: general patient characteristics, disease characteristics (including diabetes and DME), previous treatment for VI due to DME, and treatment prescribed at inclusion. Results: Of the 1023 screened patients, 918 were included in the study (Figure 1). The mean age of the patients was 67.0 years with an average 18.9 years of diabetes; 53.1% were male and 67.3% had bilateral DME (Table 1). For this analysis we included 1321 eyes with VI due to DME (BCVA ≤ 20/40; Figure 1). The majority of eyes (64.6%) had received prior treatment for reduction in BCVA due to DME. In the analyzed eyes, anti-VEGF (49.6%) was the most frequently prescribed treatment at inclusion followed by monitoring alone (41.1%). 65.9% of eyes with monitoring alone had received prior treatment. Corticosteroids were prescribed for 6.5% of eyes, while only 2.2% of eyes received laser. The mean BCVA and central retinal thickness were 53.5 letters and 415 μ m, respectively. Overall, 57.8% of eyes presented non-proliferative DR. In the treatment naïve eyes (n=459), 50.5% received ranibizumab, 40.5% had monitoring alone, and 3.9% each received laser and corticosteroids, respectively. Conclusions: The BOREAL DME study findings suggest that, in real-life practice in France, anti-VEGFs, primarily ranibizumab 0.5 mg, are the primary treatment for VI due to DME, followed by monitoring alone in 2014. Macular laser is currently rarely used in the French population

Management of diabetic macular edema with visual impairment in real-life practice in France: findings from the cross-sectional BOREAL DME study

Purpose: Diabetic macular edema (DME) is the leading cause of visual impairment (VI) in patients with diabetes. With the introduction of anti-vascular endothelial growth factor (anti-VEGF) agents, management of DME has evolved. The aim of this study was to identify the routine practice for the management of patients with VI due to DME (best-corrected visual acuity [BCVA] ≤ 20/40) in France in 2014. Methods: The cross-sectional, observational BOREAL DME study was conducted in a real-life practice in France on request of health authority. The study included patients with Type 1 or 2 diabetes aged ≥ 18 years who had a reduction in BCVA due to DME ( ≤ 20/40) irrespective of treatment prescribed at inclusion (including monitoring alone). The following medical data were collected from patients’ medical files: general patient characteristics, disease characteristics (including diabetes and DME), previous treatment for VI due to DME, and treatment prescribed at inclusion. Results: Of the 1023 screened patients, 918 were included in the study (Figure 1). The mean age of the patients was 67.0 years with an average 18.9 years of diabetes; 53.1% were male and 67.3% had bilateral DME (Table 1). For this analysis we included 1321 eyes with VI due to DME (BCVA ≤ 20/40; Figure 1). The majority of eyes (64.6%) had received prior treatment for reduction in BCVA due to DME. In the analyzed eyes, anti-VEGF (49.6%) was the most frequently prescribed treatment at inclusion followed by monitoring alone (41.1%). 65.9% of eyes with monitoring alone had received prior treatment. Corticosteroids were prescribed for 6.5% of eyes, while only 2.2% of eyes received laser. The mean BCVA and central retinal thickness were 53.5 letters and 415 μ m, respectively. Overall, 57.8% of eyes presented non-proliferative DR. In the treatment naïve eyes (n=459), 50.5% received ranibizumab, 40.5% had monitoring alone, and 3.9% each received laser and corticosteroids, respectively. Conclusions: The BOREAL DME study findings suggest that, in real-life practice in France, anti-VEGFs, primarily ranibizumab 0.5 mg, are the primary treatment for VI due to DME, followed by monitoring alone in 2014. Macular laser is currently rarely used in the French population

Varia

Numéro édité par les Presses universitaires de Perpignan

Kingship in Western Tibet in the 10th and 11th Centuries

Cet article, basé principalement sur des inscriptions, des textes historiographiques et des peintures, pose un regard nouveau sur la royauté dans l’ouest du Tibet aux dixième et onzième siècles. Le modèle de royauté adopté après la fondation du royaume de l’Ouest tibétain peut être associé à celui déjà existant pendant l’empire tibétain (du septième au neuvième siècle). Toutefois, les auteurs de cet article constatent qu’entre c. 932 et 986 (« phase formative I » ), les structures socio-politiques et les cultures religieuses qui étaient auparavant dominantes dans la région (appartenant autrefois au royaume de Zhangzhung) furent transformées de telle façon qu’elles participèrent, à partir de 986 (début de la « phase formative II » ), à la transformation bouddhique ou « mandala-fication » du royaume. En particulier, cet article analyse, en utilisant les approches méthodologiques de l’anthropologie sociale historique et de l’histoire de l’art, les hautes fonctions politiques et religieuses de la royauté : celles du souverain (btsan po) et des hommes de la famille royale appelés podrang (pho brang), qui, après leur ordination, avaient le devoir de protéger le domaine du Vinaya et les enseignements bouddhiques. L’approche par l’histoire de l’art explique l’importance des représentations des donateurs contemporains dans les monuments bouddhiques de Tabo (Spiti, Himachal Pradesh, Inde) et de Toling (Tsamda, RAT, Chine). Les frises dans le hall d’entrée de Tabo (c. 998) commémorent l’acte de la donation et de la consécration, pourvoyeur de mérite : le souverain ordonné Yeshé Ö (Ye shes ’od) conduisant la famille royale, les pratiquants laïcs et son fils Devarāja en tant que chef spirituel de la communauté des moines et des nonnes. Les peintures, qui couvrent complètement les murs bas sur les côtés, donnent à voir une société stratifiée dans un ordre spatial strict. Dans la dernière phase de rénovation, c. 1042, le moine-cum-prince royal Jangchup Ö (Byang chub ’od) est représenté par une image condensée de la royauté dans laquelle la hiérarchie est exprimée par sa position centrale et sa taille proportionnellement plus grande. Les positions, les gestes et les tenues des personnages secondaires représentant les membres des différents groupes de la société témoignent de leur allégeance et expriment l’idée de cohésion sociale. Cette nouvelle forme de portrait de groupe renforce les idéologies de l’époque : le rôle exceptionnel du lama royal Jangchup Ö dans les années 1037-1057 au centre d’un domaine politique révèle une superposition singulière de signes religieux et temporels de la souveraineté.Jahoda Christian, Kalantari Christiane. Kingship in Western Tibet in the 10th and 11th Centuries. In: Cahiers d'Extrême-Asie, vol. 24, 2015. Kingship, Ritual, and Narrative in Tibet and the Surrounding Cultural Area / Royauté, rituel et narration au Tibet et dans l'aire culturelle alentour. pp. 77-103