11 research outputs found
Investigation of neuromodulation of the endbulb of Held synapse in the cochlear nucleus by serotonin and norepinephrine
No full textOpen-Access-Publikationsfonds 202
GPU-accelerated atmospheric chemical kinetics in the ECHAM/MESSy (EMAC) Earth system model (version 2.52)
No full textThis paper presents an application of GPU accelerators in Earth system
modeling. We focus on atmospheric chemical kinetics, one of
the most computationally intensive tasks in climate–chemistry model simulations. We developed a software package that automatically
generates CUDA kernels to numerically integrate atmospheric chemical kinetics in the global climate model ECHAM/MESSy Atmospheric
Chemistry (EMAC), used to study climate change and air quality scenarios. A source-to-source compiler outputs a CUDA-compatible
kernel by parsing the FORTRAN code generated by the Kinetic PreProcessor (KPP) general analysis tool. All Rosenbrock methods that
are available in the KPP numerical library are supported.Performance evaluation, using Fermi and Pascal CUDA-enabled GPU accelerators, shows achieved speed-ups of 4. 5 × and
20. 4 × , respectively, of the kernel execution time. A node-to-node real-world production performance comparison shows a 1. 75 × speed-up
over the non-accelerated application using the KPP three-stage Rosenbrock solver. We provide a detailed description of the code
optimizations used to improve the performance including memory optimizations, control code simplification, and reduction of idle
time. The accuracy and correctness of the accelerated implementation are evaluated by comparing to the CPU-only code of the
application. The median relative difference is found to be less than 0.000000001 % when comparing the output of the accelerated
kernel the CPU-only code.The approach followed, including the computational workload division, and the developed GPU solver code can potentially be used as the
basis for hardware acceleration of numerous geoscientific models that rely on KPP for atmospheric chemical kinetics applications
Markoff-Rosenberger triples in arithmetic progression
No full textWe study the solutions of the Rosenberg–Markoff equation ax2 + by2 + cz2 = dxyz (a generalization of the well–known Markoff equation). We specifically focus on looking for solutions in arithmetic progression that lie in the ring of integers of a number field. With the help of previous work by Alvanos and Poulakis, we give a complete decision algorithm, which allows us to prove finiteness results concerning these particular solutions. Finally, some extensive computations are presented regarding two particular cases: the generalized Markoff equation x 2 +y 2 +z 2 = dxyz over quadratic fields and
the classic Markoff equation x 2 + y 2 + z 2 = 3xyz over an arbitrary number
field.Ministerio de Ciencia e InnovaciónJunta de AndalucíaFondo Social EuropeoFondo Europeo de Desarrollo Regiona
Retinal Nerve Fiber Layer Thickness in Patients with Exfoliation, Exfoliative Glaucoma, and Primary Open Angle Glaucoma
No full textPurpose T ev lu te the retin I nerve fi er I yer (RNFL) pr file f he Ithy ntr Is, pers ns with exf - li ti n syndr me (XFS), nd p tients with exf li ti n gl u m (XFG) nd prim ry pen ngle gl u - m (POAG). Methods One eye fr m e h f 269 p rti ip nts w s n lyzed. Fifty eyes were n rm I, 45 eyes h d XFS, 89 eyes h d POAG, nd 89 h d XFG. Gl u m p tients were divided rding t the severity f the dise se int mild nd dv n ed gr ups. All p rti ip nts underwent im ging with the GDx-VCC devi e. Me surements f the p r meters TSNIT ver ge, TSNIT SD, nd nerve fi er indi t r (NFI) were perf rmed. P I rimetri RNFL thi kness v lues were mp red y me ns f B nferr ni- rre - ted t-tests. Results Reg rding ntr I nd gl u m gr ups, st tisti lly signifi nt differen es were identified in II GDx p r meters. RNFL thi kness v lues f the ntr I gr up differed signifi ntly fr m the v lues f the XFS gr up. There w s n st tisti lly signifi nt differen e etween RNFL thi kness v lues f r the mild POAG nd mild XFG gr ups rf rthe dv n ed POAG nd dv n ed XFG gr ups. Conclusions P I rimetry-determined RNFL in eyes with XFS is thinner th n th t f he Ithy eyes. N differen es in RNFL thi kness were f und when eyes with POAG nd XFG f simil r seventy were mp red. </jats:sec
Efficient and sustained optogenetic control of sensory and cardiac systems
No full textAbstract Optogenetic control is used to manipulate the activity of specific cell types in vivo for a variety of biological and clinical applications. Here we report ChReef, an improved variant of the channelrhodopsin ChRmine. ChReef offers minimal photocurrent desensitization, a unitary conductance of 80 fS and closing kinetics of 30 ms, which together enable reliable optogenetic control of cells at low light levels with good temporal fidelity and sustained stimulation. We demonstrate efficient and reliable red-light pacing and depolarization block of ChReef-expressing cardiomyocyte clusters. We used adeno-associated-virus-based gene transfer to express ChReef in retinal ganglion cells, where it restores visual function in blind mice with light sources as weak as an iPad screen. Toward optogenetic hearing restoration, ChReef enables stimulation of the auditory pathway in rodents and non-human primates with nanojoule thresholds, enabling efficient and frequency-specific stimulation by LED-based optical cochlear implants
Efficient and sustained optogenetic control of sensory and cardiac systems
No full textOptogenetic control is used to manipulate the activity of specific cell types in vivo for a variety of biological and clinical applications. Here we report ChReef, an improved variant of the channelrhodopsin ChRmine. ChReef offers minimal photocurrent desensitization, a unitary conductance of 80 fS and closing kinetics of 30 ms, which together enable reliable optogenetic control of cells at low light levels with good temporal fidelity and sustained stimulation. We demonstrate efficient and reliable red-light pacing and depolarization block of ChReef-expressing cardiomyocyte clusters. We used adeno-associated-virus-based gene transfer to express ChReef in retinal ganglion cells, where it restores visual function in blind mice with light sources as weak as an iPad screen. Toward optogenetic hearing restoration, ChReef enables stimulation of the auditory pathway in rodents and non-human primates with nanojoule thresholds, enabling efficient and frequency-specific stimulation by LED-based optical cochlear implants
Evliyâ Çelebi et l'Europe
No full textL’essentiel de ce volume est consacré au dossier intitulé Evliyâ Çelebi et l’Europe. Il est issu du colloque international, organisé, les 14-15 novembre 2011, à l’Institut National des Langues et Civilisations orientales (INALCO), à l’occasion du 400e anniversaire de la naissance du voyageur ottoman (1611-1684 ?). L’année 2011 a été déclarée par l’UNESCO « Année Evliyâ Çelebi » et nous avons mis à profit ce moment exceptionnel pour analyser à travers le Seyahatnâme (Livre de voyages), la vision, réelle ou imaginaire, qu’Evliyâ avait de l’Europe et de ses habitants. En effet, au cours de plus des quatre décennies de ses voyages, Evliyâ avait aussi parcouru le Caucase, l’Iran, l’Arabie et l’Égypte, mais une partie relativement importante des dix volumes de sa relation concerne l’Europe balkanique et danubienne sous autorité ottomane, aussi bien que le « Pays des Francs ». L’auteur juxtapose, selon son habitude, des descriptions d’une minutieuse exactitude à des histoires invraisemblables, divertissantes et parfois grivoises. C’est un tel mélange qui donne à son ouvrage sa saveur inimitable, en tout cas dans les littératures de l’Orient islamique, que nous souhaiterions faire connaître plus largement sous nos climats. Ce numéro présente également quelques-unes des communications faites lors d'une Journée d'études et d'un Colloque organisés par le CEB-INALCO, La Grèce à la Une : regards de la presse française sur la Grèce au XXe siècle, et Femmes des Balkans sous l'Occupation. The main part of this volume is dedicated to the file entitled “Evliyâ Çelebi and Europe”. It is derived from the international Symposium organized in 2011, November 14-15, at the National Institute of Oriental Languages and Civilizations (INALCO) in Paris on the occasion of the 400th anniversary of the birth of the ottoman traveller (1611-1684 ?). Year 2011was declared by UNESCO “Evliyâ Çelebi’s Year” and we used this exceptional moment to analyse, through the Seyahatnâme (Travelogue), the vision, real or imaginary, that Evliyâ had formed about Europe and its inhabitants. Having travelled more than four decades, he had been through Caucasus, Iran, Arabia and Egypt too, but a relatively important part of his ten volumes, deals with the under ottoman authority Balkan and Danubian Europe, as well as the “Frank country”. The author, as usual, puts side by side, descriptions of minute accuracy and improbable, entertaining and sometimes bawdy stories. Such a mixture gives to his books the inimitable flavor, in the literature of the Islamic East in any case, that we wish to be more widely known in our climates. The present issue presents papers from one Study Day and a Symposium organized by the INALCO-CEB (Centre for Balkan studies), “Greece in the Front page: of the French press on Greece in the 20th century”, and “Balkan women during the Occupation”. Το σημαντικό μέρος αυτού του τεύχους αφιερώνεται σ’ένα φάκελο με τίτλο «Ο Εβλιγιάς Τσελεμπί και η Ευρώπη». Γεννήθηκε από το διεθνές Συμπόσιο οργανωμένο το 14 και 15 Νοεμβρίου του 2011, στο Εθνικό Ινστιτούτο των Ανατολικών Γλωσσών και Πολιτισμών [INALCO] στο Παρίσι, με την ευκαιρία των 400ων γενεθλιών της γεννήσεως του οθωμανού ταξιδιώτη [1611-1684;]. Το 2011 κηρύχτηκε από το ΟΥΝΕΣΚΟ «Χρονιά του Εβλιγιά Τσελεμπί» και χρησιμοποιήσαμε αυτή την εξαιρετική στιγμή για να αναλύσουμε, μέσω το Σεχαγιατνάμε [Βιβλίο των ταξιδιών] το όραμα, πραγματικό ή φανταστικό, το οποίο είχε ο Εβλιγιάς για την Ευρώπη και τους κατοίκους της. Πράγματι, σε περισσότερα από τέσσερις δεκαετίες ταξιδιών, ο Εβλιγιάς είχε διασχίσει και τον Καύκασο, τον Ιράν, την Αραβία και την Αίγυπτο, όμως ένα σχετικά σημαντικό μέρος της αφήγησής του αφορά την βαλκανική και δουναβική Ευρώπη και τη «χώρα των Φράγκων». Ο συγγραφέας βάζει πλάι πλάι περιγραφές με σχολαστική ακρίβεια και απίθανες ιστορίες, διασκεδαστικές και μερικές φορές ανήθικες. Τέτοιο μίγμα δίνει στο έργο του μια αμίμητη γεύση, τουλάχιστον μέσα στις λογοτεχωνίες της ισλαμικής Ανατολής και αυτό ακριβώς θέλουμε να γνωστοποιήσουμε ευρύτερα στα μέρη μας. Αυτό το τεύχος παρουσιάζει επίσης μερικές από τις διαλέξεις οι οποίες έγιναν κατά την διάρκεια μιας Μέρας Μελέτης και ένα Συμπόσιο οργανωμένο από το INALCO-CEB [Κέντρο Βαλκανικών Σπουδών], «Η Ελλάδα στην Πρώτη σελίδα, ο γαλλικός τύπος και η Ελλάδα το 20ο αιώνα», και «Γυναίκες των Βαλκανιών στην Κατοχή»
