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51.
Machine Learning - Probabilistic logic programming (PLP) combines logic programs and probabilities. Due to its expressiveness and simplicity, it has been considered as a powerful tool for learning... 相似文献
52.
53.
Julien Arnaud Daniel Négru Mamadou Sidibé Julien Pauty Harilaos Koumaras 《Multimedia Tools and Applications》2011,55(2):333-352
Heterogeneous communication devices are emerging and changing the way of communication. Innovative multimedia applications
are now accessible through these embedded systems. The 3GPP IP Multimedia Subsystem (IMS) provides a basic architecture framework
for the Next Generation Network (NGN) supporting the convergence platform for service provisioning in heterogeneous networks.
ETSI TISPAN standardization effort focuses on delivering IPTV services on such platform. Nevertheless, IPTV on IMS standardization
suffers from a lack of efficient user-centric network management mechanisms as the end-user may consume IPTV service from
different access networks, on different mobile devices, at anytime. User’s Perceived Quality of Service (PQoS) or Quality
of Experience (QoE) of IPTV service may also suffer from wireless access network impairments. This paper introduces new functionalities
in IPTV over IMS architecture which optimize satisfaction of the end-user and resource utilization of the operator’s networks.
A context-sensitive User Profile (UP) model is used to deliver IPTV streams adapted to the user’s environment. In order to
optimize the operator network usage, the impact of spatiotemporal dynamics of the video content on the deduced perceptual
quality is considered. A Multimedia Content Management System (MCMS) is proposed to perform dynamic cross-layer adaptation
of the IPTV stream based on PQoS measurements at the end-user side. 相似文献
54.
Mohamad El Khatib Arnaud Pothier Aurelian Crunteanu Pierre Blondy 《Microsystem Technologies》2007,13(11-12):1457-1461
This paper reports the design of a hermetic-compatible wafer-scale package for RF MEMS based components. The presented packaging concept consists in encapsulating the whole RF device or subsystem instead of encapsulating each MEMS component separately, which will reduce the device size and cost. This approach is based on the MEMS fabrication technology on ceramic substrate and the use of laser drilled vias hole techniques to realize full metallized vias in alumina substrates. These vias holes will allow a low loss RF signal transmission inside the package without breaking its hermeticity. Hence, several packaged switching networks prototypes, based on ohmic contact MEMS switches, have been designed following this approach and the packaging electromagnetic impact on these components has been especially studied to result on good performance devices. 相似文献
55.
Andrea Bianchi Sandrine Dufort François Lux Arnaud Courtois Olivier Tillement Jean-Luc Coll Yannick Crémillieux 《Magma (New York, N.Y.)》2014,27(4):303-316
Objective
To study the biodistribution and lung pharmacokinetics of tracheally administered gadolinium-based contrast agents [gadoteric acid and multimodal ultra-small rigid platforms (USRPs)], to validate their pharmacokinetics against optical imaging of fluorescent USRPs, and to test their short-term toxicity.Materials and methods
Ultrashort echo-time (UTE) lung proton magnetic resonance imaging (MRI) was performed at 4.7-Tesla (T) after the intratracheal instillation of different concentrations of contrast agent solutions in mice. Pharmacokinetic models were implemented on the absolute concentration calculated from the MRI signal enhancement measurements. Fluorescent USRPs were used to obtain optical images with the same protocol. Bronchoalveolar lavage inflammatory cell count and serum creatinine measurement were performed on four groups of instilled mice (sham, saline, USRPs, lipopolysaccharide).Results
MR and optical imaging showed similar kinetics of the USRPs, passing from the airways to the lung tissue and to the kidneys, with negligible hepatic clearance. No significant increase of lung and renal inflammation markers were observed in USRP-instilled animals.Conclusion
A T 1-weighted radial UTE sequence was found to be valuable in quantitatively monitoring the biodistribution and pharmacokinetics of nanoparticles in the lungs of mice. The observed favorable pharmacokinetics, which was validated by fluorescence imaging, ensures the negligible toxicity of the nanoprobes, making the USRPs and the developed protocol good candidates for applications on selected lung diseases. 相似文献56.
Damien Querlioz Philippe Dollfus Van-Nam Do Arnaud Bournel Van Lien Nguyen 《Journal of Computational Electronics》2006,5(4):443-446
We present an original approach to including quantum transport into classical Ensemble Monte Carlo (EMC) simulations. The
method, based on the Wigner transport equation, is fully self-consistent, and includes impurity and phonon scattering according
to the Fermi Golden rule. It is inspired by an approach suggested by Shifren et al. [IEEE Trans. Electron Dev. 50, 769 (2003)],
with some major improvements that make possible successful comparison with other simulation techniques and experiments. 相似文献
57.
Adil Maarouf Bertrand Audoin Simon Konstandin Audrey Rico Elisabeth Soulier Françoise Reuter Arnaud Le Troter Sylviane Confort-Gouny Patrick J. Cozzone Maxime Guye Lothar R. Schad Jean Pelletier Jean-Philippe Ranjeva Wafaa Zaaraoui 《Magma (New York, N.Y.)》2014,27(1):53-62
Object
Sodium accumulation is involved in neuronal injury occurring in multiple sclerosis (MS). We aimed to assess sodium accumulation in progressive MS, known to suffer from severe neuronal injury.Materials and methods
3D-23Na-MRI was obtained on a 3T-MR-scanner in 20 progressive MS patients [11 primary-progressive (PPMS) and nine secondary-progressive (SPMS)] and 15 controls. Total sodium concentrations (TSC) within grey matter (GM), normal-appearing white matter (WM) and lesions were extracted. Statistical mapping analyses of TSC abnormalities were also performed.Results
Progressive MS patients presented higher GM–TSC values (48.8 ± 3.1 mmol/l wet tissue vol, p < 0.001) and T2lesions-TSC values (50.9 ± 2.2 mmol/l wet tissue vol, p = 0.01) compared to GM and WM of controls. Statistical mapping analysis showed TSC increases in PPMS patients confined to motor and somatosensory cortices, prefrontal cortices, pons and cerebellum. In SPMS, TSC increases were associated with areas involving: primary motor, premotor and somatosensory cortices; prefrontal, cingulate and visual cortices; the corpus callosum, thalami, brainstem and cerebellum. Anterior prefrontal and premotor cortices TSC were correlated with disability.Conclusion
Sodium accumulation is present in progressive MS patients, more restricted to the motor system in PPMS and more widespread in SPMS. Local brain sodium accumulation appears as a promising marker to monitor patients with progressive MS. 相似文献58.
A (Triphenylphosphine)Silver (I) Complex as a New Performance Additive in Free‐Radical Photopolymerization under Air 下载免费PDF全文
Pauline Sautrot‐Ba Nicolas Bogliotti Arnaud Brosseau Julie Bourgon Pierre‐Emmanuel Mazeran Jacques Lalevée Fabrice Morlet‐Savary Davy‐Louis Versace 《大分子材料与工程》2018,303(8)
Unusual photochemical properties of an Ag(I)‐derived complex, i.e., bis[(µ‐chloro)bis(triphenylphosphine)silver (I)] ([Ag](PPh3)) are demonstrated when used in free‐radical photopolymerization reactions: i) [Ag](PPh3) can act as an innovative photoinitiating system when associated with a commercial type I photoinitiator 2,2‐dimethoxy‐2‐phenylacetophenone to overcome the oxygen inhibition effect during the free‐radical photopolymerization of acrylate monomers, thus accelerating the kinetics of polymerization under air; ii) silver‐based nanoparticles can be in situ generated under air, thus leading to new antibacterial coatings which prevent the growth of Escherichia coli and Staphylococcus aureus after few hours of incubation. 相似文献
59.
Blondel Arnaud; Nageotte Roland; Bedouelle Hugues 《Protein engineering, design & selection : PEDS》1996,9(2):231-238
Hybrid MalEGVP is a bifunctional protein in vitro sinceit binds maltose as protein MalE of Escherichia coli and sinceit is dimeric and specifically binds single-stranded DNA asprotein GVP of phage M13. The oxidation rate of a unique cysteineresidue was used to compare the stabilities of GVP in its freeand hybrid forms, under conditions where MalE was either foldedor unfolded by a denaturing agent. The results showed that boththe covalent link and tertiary non-covalent interactions betweenMalE and GVP destabilized GVP in MalEGVP. To test whetherGVP had identical structures in its free and hybrid forms, mutationswere used as local conformational probes. The effects of thesemutations on the capabilities of MalEGVP to dimerizeand to bind single-stranded DNA were assayed in vitro. Theywere compatible with the effects of the same mutations on theglobal activity of free GVP in vivo and with the effects thatcould be predicted from the known data on free GVP, in particularits crystal structure. Thus, one partner of a hybrid proteincan be destabilized by the other partner while maintaining itsstructural and functional characteristics. 相似文献
60.
Valentin Magn Florent Blanchard Angela Marinetti Arnaud Voituriez Xavier Guinchard 《Advanced Synthesis \u0026amp; Catalysis》2016,358(21):3355-3361
N‐Propargyl‐ and N‐homoallenyl‐2‐bromo‐β‐tryptamines undergo gold(I)‐catalyzed dearomatizing cyclizations to afford 2‐bromospiroindolenines that are in situ hydrolyzed to furnish spirooxindoles in a one‐pot process. Tryptophane derivatives (R2=CO2Et) led upon cyclization to chiral spirooxindoles in excellent diastereoselectivities.