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71.
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
72.
Antonio Brogi Jean-Marie Jacquet Isabelle Linden 《Electronic Notes in Theoretical Computer Science》2003,68(3):284
The paper proposes a theoretical study of a coordination language embodying Linda's asynchronous communication primitive with a refined matching mechanism based on pairs composed of attribute names associated with their values. Computations in this language are described by means of an operational semantics, reporting the whole traces of executions. The non-compositionality of this intuitive operational semantics motivates the design of a compositional and fully abstract denotational semantics, which is then exploited for studying program equivalence in this setting. 相似文献
73.
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
74.
Rizza G Attouchi F Coulon PE Perruchas S Gacoin T Monnet I Largeau L 《Nanotechnology》2011,22(17):175305
We have studied how spherical 23 ± 3 nm Au(45)Ag(55) nanoparticles embedded within a silica matrix transform into prolate nanorods and nanowires by irradiating them with swift heavy ions. Samples were irradiated at room temperature and normal incidence with 74 MeV Kr and 36 MeV S ions for fluences up to 1.0 × 10(15) cm(-2). We demonstrate the existence of two regimes: (i) below a critical fluence, ~ 2.0 × 10(14) cm(-2), the transformation of the spherical nanoparticle into a nanorod is an individual process, i.e. each nanoparticle transforms into a single nanorod; (ii) for larger fluences the transformation from nanorod to nanowire becomes a collective process, i.e. the break up and dissolution of unstable nanorods contribute to the growth of long nanowires. The passage from the first to the second regime can be interpreted in terms of a Rayleigh-like instability under irradiation. The latter becomes active when the diameter of the nanowire approaches its saturation width under irradiation. Furthermore, we show that the composition of the alloy is only slightly modified during the ion-shaping process. Finally, the energy and the fluence thresholds for deformation and the deformation strain-rate are estimated. 相似文献
75.
Graulières E Lotterie JA Cassol E Gerdelat A Clanet M Berry I 《Magma (New York, N.Y.)》2009,22(2):89-100
Object To this day, no parameter can really monitor the progression of multiple sclerosis (MS). In this study, an index the skewness
(S) derived from parameters calculated in diffusion tensor imaging (DTI) has been tested on MS patients for its ability to
monitor the disease course.
Materials and methods Eighteen patients underwent two examinations within 3 months consisting of a clinical evaluation (EDSS) and DTI acquisitions
on a 1.5 T imager. Tensor was calculated thanks to“home-made” software. Mean diffusivity (MD) and fractional anisotropy (FA)
histograms were described for normal-appearing white matter (NAWM) and gray matter (GM) of patients with S and also with usually
indices peak position (pp) and peak height (ph) for the whole group of patients and for two separate groups according to their
clinical status (EDSS ≤ 3 and EDSS > 3 at month 0).
Results Although no significant clinical evolution is observed over 3 months, S in GM showed a significant shift for both MD/FA histograms
towards abnormal values for the whole group of patients (p = 0.02/p = 0.04) and for the group with EDSS ≤ 3 (p = 0.04/p = 0.007), while ph and pp do not.
Conclusion S in GM could be an alternative marker to monitor the disease course before the repercussion on the clinical score. 相似文献
76.
77.
Jean Berstel Luc Boasson Olivier Carton Isabelle Fagnot 《Theory of Computing Systems》2010,46(3):443-478
We consider Sturmian trees as a natural generalization of Sturmian words. A Sturmian tree is a tree having n+1 distinct subtrees of height n for each n. As for the case of words, Sturmian trees are irrational trees of minimal complexity. 相似文献
78.
Gallet C Ibanez S Zinger L Taravel FR Trierweiler M Jeacomine I Despres L 《Journal of chemical ecology》2007,33(11):2078-2089
Plant-seed parasite pollination mutualisms involve a specific pollinator whose larvae develop by consuming a fraction of the
host plant seeds. These mutualisms are stable only if the plant can control seed destruction by the larvae. Here, we studied
the chemical response of the European globeflower Trollius europaeus to infestation by an increasing number of Chiastocheta fly larvae. We used liquid chromatographic analysis to compare the content of phenolic compounds in unparasitized and parasitized
fruits collected in two natural populations of the French Alps, and mass spectrometry and nuclear magnetic resonance to elucidate
the structure of adonivernith, a C-glycosyl-flavone. This compound is present in many of the organs of T. europaeus, but not found in other Trollius species. Furthermore, it is overproduced in the carpel walls of parasitized fruits, and this induced response to infestation
by fly larvae is density-dependent (increases with larval number), and site-dependent (more pronounced in the high-altitude
site). Mechanical damage did not induce adonivernith production. This tissue-specific and density-dependent response of T. europaeus to infestation by Chiastocheta larvae might be an efficient regulation mechanism of seed-predator mutualist population growth if it decreases survival or
growth of the larvae. 相似文献
79.
Isabelle L. Di Ma?o Pascale Barbier Diane Allegro Cédric Brault Vincent Peyrot 《International journal of molecular sciences》2014,15(8):14697-14714
The interaction between the microtubule associated protein, tau and the microtubules is investigated. A fluorescence resonance energy transfer (FRET) assay was used to determine the distance separating tau to the microtubule wall, as well as the binding parameters of the interaction. By using microtubules stabilized with Flutax-2 as donor and tau labeled with rhodamine as acceptor, a donor-to-acceptor distance of 54 ± 1 Å was found. A molecular model is proposed in which Flutax-2 is directly accessible to tau-rhodamine molecules for energy transfer. By titration, we calculated the stoichiometric dissociation constant to be equal to 1.0 ± 0.5 µM. The influence of the C-terminal tails of αβ-tubulin on the tau-microtubule interaction is presented once a procedure to form homogeneous solution of cleaved tubulin has been determined. The results indicate that the C-terminal tails of α- and β-tubulin by electrostatic effects and of recruitment seem to be involved in the binding mechanism of tau. 相似文献
80.
Isabelle Gachard Soufiane Bechaouch Bernard Coutin Hikaru Sekiguchi 《Polymer Bulletin》1997,38(4):427-431
New nonpeptidic α-amino acid-based polyamides were used for drug delivery. Benzocaine was covalently linked via a spacer to N-protected poly(l-cystyl-l-cystine) and to poly(adipoyl-l-lysine). Its release by α-chymotrypsin attack was followed by UV. It was nearly quantitative within two days with l-cystine-based polyamide. Protected forms of these polyamides were used as matrices. Release of benzocaine entrapped in polyamide
from (l-cystine) was controlled by diffusion. When entrapped in polyamide from (l-lysine) it was controlled by diffusion and swelling.
Received: 10 January 1997/Accepted: 23 January 1997 相似文献