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61.
Isabelle Corre Ma?va Guillonneau Fran?ois Paris 《International journal of molecular sciences》2013,14(11):22678-22696
Tumor areas can now be very precisely delimited thanks to technical progress in imaging and ballistics. This has also led to the development of novel radiotherapy protocols, delivering higher doses of ionizing radiation directly to cancer cells. Despite this, radiation toxicity in healthy tissue remains a major issue, particularly with dose-escalation in these new protocols. Acute and late tissue damage following irradiation have both been linked to the endothelium irrigating normal tissues. The molecular mechanisms involved in the endothelial response to high doses of radiation are associated with signaling from the plasma membrane, mainly via the acid sphingomyelinase/ceramide pathway. This review describes this signaling pathway and discusses the relevance of targeting endothelial signaling to protect healthy tissues from the deleterious effects of high doses of radiation. 相似文献
62.
Nadhir Gourine Mohamed Yousfi Isabelle Bombarda Boubakeur Nadjemi Emile Gaydou 《Journal of the American Oil Chemists' Society》2010,87(2):157-166
The composition and antioxidant activities of Pistacia atlantica Desf. essential oil were investigated. Qualitative and quantitative differences in compositions and in antioxidant activities
of male and female leaf essential oils were observed during the season. The essential oils obtained by hydrodistillation were
analysed by GC and GC–MS. The oils were rich in monoterpenes hydrocarbons and oxygenated sesquiterpenes. The main components
of male essential oil were α-pinene/α-thujene, spathulenol and bicyclogermacrene. The major component of female essential oil was δ-3-carene. The seasonal variation showed that most of the main components of the oils reached theirs highest values in September.
The antioxidant activity of the oil was investigated in vitro using two assays: DPPH· (2,2-di-phenyl-1-picrylhydrazyl) free radical-scavenging and FRAP (Ferric Reducing Antioxidant Power). The highest antioxidant
capacity to scavenge free DPPH radicals was reached in the month of June for male oils and during the months of September–October
for the female oils. The high reducing power for male oil was observed during the month of June and for the female oil it
was in August. The female oil was more active than the male oil. The antioxidant capacity of the female oil was almost ten
times higher than Ascorbic acid in the FRAP assay. 相似文献
63.
64.
Jordan A. Doumanov Christina Zeitz Paloma Dominguez Gimenez Isabelle Audo Abhay Krishna Giovanna Alfano Maria Luz Bellido Diaz Veselina Moskova-Doumanova Marie-Elise Lancelot José-Alain Sahel Emeline F. Nandrot Shomi S. Bhattacharya 《International journal of molecular sciences》2013,14(7):15121-15140
65.
66.
Gorce JM Friboulet D Dydenko I D'hooge J Bijnens BH Magnin IE 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2002,49(12):1704-1719
Spectral estimation is a major component in studies aiming at characterizing biological tissues through the analysis of backscattered radio frequency (RF) ultrasonic signals and images. However, conventional spectral estimation techniques yield a well-known trade-off between spatial resolution and variance. The backscattered signals are stochastic by nature, so short-term local analysis results in a high variance of the estimates, which cannot efficiently be reduced through conventional spatial averaging. We address this issue by describing a spectral estimation technique that reduces the variance of the estimates (by smoothing the local estimates in spectrally homogeneous regions) while preserving spectral discontinuities (i.e., the smoothing is not performed across regions with different spectral contents). The proposed approach is set in a Bayesian framework and is based on local autoregressive (AR) estimation, constrained by smoothness priors. These smoothness priors are introduced through a Markov random field in which the associated potential functions are nonquadratic, allowing thereby to preserve discontinuity. The method is validated on simulated RF images and tested on echocardiographic images acquired in vivo. The results are compared to the estimates provided by the conventional Burg technique. These results clearly demonstrate the ability of the proposed approach to improve spectral estimation in terms of variance reduction and discontinuity detection. 相似文献
67.
There has been an explosion of interest in health sciences applications of case-based reasoning (CBR), not only in the traditional CBR in medicine domain, but also in bioinformatics, enabling home health-care technologies, CBR integration, and synergies between CBR and knowledge discovery. This special issue features the best papers from the third workshop on CBR in the health sciences, held at ICCBR-05 in Madrid. It is the third in a series of exciting workshops, the first two of which were held at ICCBR-03, in Trondheim, Norway, and at ECCBR-04, in Madrid, Spain. The nine high-quality papers introduced here represent the research and experience of twenty-two authors working in eight different countries on a wide range of problems and projects. These papers illustrate some of the major trends of current research in CBR in the health sciences, and represent overall an excellent sample of the most recent advances of CBR in the health sciences. 相似文献
68.
Fabio Casati Maria Grazia Fugini Isabelle Mirbel Barbara Pernici 《Requirements Engineering》2002,7(2):73-106
Workflow management systems are becoming a relevant support for a large class of business applications, and many workflow
models as well as commercial products are currently available. While the large availability of tools facilitates the development
and the fulfilment of customer requirements, workflow application development still requires methodological guidelines that
drive the developers in the complex task of rapidly producing effective applications. In fact, it is necessary to identify
and model the business processes, to design the interfaces towards existing cooperating systems, and to manage implementation
aspects in an integrated way. This paper presents the WIRES methodology for developing workflow applications under a uniform
modelling paradigm – UML modelling tools with some extensions – that covers all the life cycle of these applications: from
conceptual analysis to implementation. High-level analysis is performed under different perspectives, including a business and an organisational perspective. Distribution, interoperability and cooperation with external information systems are considered in this early
stage. A set of “workflowability” criteria is provided in order to identify which candidate processes are suited to be implemented
as workflows. Non-functional requirements receive particular emphasis in that they are among the most important criteria for
deciding whether workflow technology can be actually useful for implementing the business process at hand. The design phase
tackles aspects of concurrency and cooperation, distributed transactions and exception handling. Reuse of component workflows,
available in a repository as workflow fragments, is a distinguishing feature of the method. Implementation aspects are presented
in terms of rules that guide in the selection of a commercial workflow management system suitable for supporting the designed
processes, coupled with guidelines for mapping the designed workflows onto the model offered by the selected system. 相似文献
69.
Thierry Klein Isabelle Joumard Jacques Marcus Robert Cubitt 《Journal of Low Temperature Physics》1999,117(5-6):1353-1357
Small Angle Neutron Scattering has been used to observe diffraction from the flux line lattice in the fully isotropic (K, Ba)BiO
3
high T
c
superconductor. We show that the flux lines are ordered into a hexagonal lattice at low field (H < H
e
0.6T H
g (0) where H
g
is the second order vortex glass transition field). The diffracted intensity continuously drops to zero as the field is increased towards H
e
. Those observations are in good agreement with recent theoritical works which suggested that the formation of dislocations becomes favorable above H
e
leading to a glassy structure. The field H
e
lies close to the onset of the second peak in magnetization measurements indicating that this peak is related to the change in the vortex structure. 相似文献
70.
Isabelle Pesneau Michel F. Champagne Michel A. Huneault 《Polymer Engineering and Science》2002,42(10):2016-2031
Dynamically cross‐linked polypropylene/ethylene‐methyl acrylate copolymer (PP/EMA) blends were prepared by reactive extrusion in a twin‐screw extruder. A transesterification reaction catalyzed by an organotin compound and involving the acrylic moieties of EMA with the hydroxyl functions of pentanediol was used to cross‐link the elastomeric EMA. The extent of cross‐linking was estimated through the insoluble content of the blend. The alcohol‐to‐acrylic ratio and the dibutyltin oxide content were both found to increase the extent of EMA cross‐linking. Processing conditions such as screw rotation rate and extrusion temperature profile also had large effects on the reaction extent. Conditions leading to improved pentanediol dispersion were found to generate larger insoluble fraction. Gel contents of EMA phase as high as 75% to 85% were obtained. Interestingly, the stress‐strain curves of the cross‐linked PP/EMA TPV are very well represented by a single master curve. Dynamically cross‐linked blends show systematically better tensile properties than the non‐reactive system. Blends with higher insoluble content show strain at break in the 650%–750% range. Material processability was maintained, even for the systems with high insoluble content. 相似文献