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91.
A confusion is sometimes made in the literature between the mass-carrying momentum of a photon, which is inversely proportional to the refractive index of the medium in which it propagates, and the momentum taken up by an absorber located in a fluid, which is directly proportional to the refractive index of the fluid. The distinction between these two momenta is clarified by considering an artificial dielectric. 相似文献
92.
Arnaud C. Feron P. Boustimi M. Grosso P. Bosc D. Guignard P. 《Electronics letters》2003,39(17):1249-1250
Numerical results on polymer surrounded by an air micro-ring coupled to waveguides are presented. The FDTD method predicts a filter width of 1.4 nm and an extraction efficiency of almost 80% for a gap of 0.15 /spl mu/m. 相似文献
93.
94.
Filters with 100 GHz free spectral range (FSR) and finesse up to 16 are demonstrated over the 1525 to 1583 nm band. The photoinduced birefringence results in a polarisation-dependent spectral response. Finesse and FSR uniformity are addressed 相似文献
95.
Legal suits against visceral surgeons have increased since the advent of laparoscopic surgery. The duties of physicians have not however changed with the development of laparoscopic techniques. Since the decree promulgated in 1936, physicians have a legal commitment to provide the means required for patient care. This obligation has been recalled in different court judgements and in the new deontology code. In addition, jurisprudence tends more and more towards responsibility without risk. Laparoscopic cholecystectomy is not risk-free. Although morbidity and mortality have not risen with laparoscopic procedures, the types of complications encountered have changed. Reported accidents have become more frequent. The number of suits against surgeons has also increased. Surgeons must therefore be highly prudent and diligent. Precautions concerning personnel management, the choice of material and its upkeep. Special care must be given to the peroperative pneumoperitoneum and the use of monopolar electrocoagulation. A peroperative cholangiogram should be obtained. A careful operative report is very important. The surgeon must be able to justify his competence. Finally, the surgical community should publish more results concerning the rate of complications in order to establish reference material for experts. 相似文献
96.
97.
The spectrum, Sp(), of a sentence is the set of cardinalities of finite structures which satisfy . We prove that any set of integers which is in Func1∞, i.e. in the class of spectra of first-order sentences of type containing only unary function symbols, is also in BIN1, i.e. in the class of spectra of first-order sentences of type involving only a single binary relation.
We give similar results for generalized spectra and some corollaries: in particular, from the fact that the large complexity class cNTIMERAM(cn) is included in Func1∞ for unary languages (n denotes the input integer), we deduce that the set of primes and many “natural” sets belong to BIN1.
We also give some consequences for the image of spectra under polynomials of . 相似文献
98.
RP Bourette S Arnaud GM Myles JP Blanchet LR Rohrschneider G Mouchiroud 《Canadian Metallurgical Quarterly》1998,17(24):7273-7281
The production, survival and function of monocytes and macrophages are regulated by the macrophage colony-stimulating factor (M-CSF or CSF-1) through its tyrosine kinase receptor Fms. Binding of M-CSF results in Fms autophosphorylation on specific tyrosines that act as docking sites for intracellular signaling molecules containing SH2 domains. Using a yeast two-hybrid screen, we cloned a novel adaptor protein which we called 'Mona' for monocytic adaptor. Mona contains one SH2 domain and two SH3 domains related to the Grb2 adaptor. Accordingly, Mona interacts with activated Fms on phosphorylated Tyr697, which is also the Grb2-binding site. Furthermore, Mona contains a unique proline-rich region located between the SH2 domain and the C-terminal SH3 domain, and is apparently devoid of any catalytic domain. Mona expression is restricted to two hematopoietic tissues: the spleen and the peripheral blood mononuclear cells, and is induced rapidly during monocytic differentiation of the myeloid NFS-60 cell line in response to M-CSF. Strikingly, overexpression of Mona in bone marrow cells results in strong reduction of M-CSF-dependent macrophage production in vitro. Taken together, our results suggest an important role for Mona in the regulation of monocyte/macrophage development as controlled by M-CSF. 相似文献
99.
We analyzed the influence of clinical and psychological factors on the long-term efficacy of botulinum toxin A (BTX) injections in 45 patients with blepharospasm and 66 patients with hemifacial spasm. Injections efficacy (respectively 94.3% and 95.7%) and duration of relief (respectively 14.8 and 18.7 weeks) remained stable over seven successive injections. Clinical improvement was not influenced by patients' sex, age, or disease duration but by psychological background (p < 0.001). Patients who failed to respond after repetitive injections had lower inter-injections intervals (p < 0.05). This data shows: (1) the importance of psychological contexte in subjective evaluation of treatment efficacy with BTX, (2) emphasizes the necessity of avoiding close injections. 相似文献
100.
Bernard Grabot Laurent Geneste Arnaud Dupeux 《Journal of Intelligent Manufacturing》1994,5(5):303-313
Most of the available industrial schedulers are based on a simulation approach using dispatching rules. These rules are often dedicated to the satisfaction of a single performance criterion, and are used whatever the characteristics of the workshop or of the set of jobs. An approach which allows one to bring in compromises between rules is set out in this paper. These compromises can be parametered in accordance with the objectives of the workshop and the characteristics of the jobs in order to introduce some reactivity in the decision system. Three ways to set up the parameters are compared: experimental design, fuzzy expert system and neural network. The method allowing one to define compromises can be implemented on each scheduler that uses a simulation approach. Tests have been made with an industrial scheduler called SIPAPLUS, the results of which are developed in this paper. 相似文献