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1.
We show that every two-bridge knot K of crossing number N admits a polynomial parametrization x = T
3(t), y = T
b
(t), z = C(t), where T
k
(t) are the Chebyshev polynomials and b + deg C = 3N. If C(t) = T
c
(t) is a Chebyshev polynomial, we call such a knot a harmonic knot. We give the classification of harmonic knots for a ≤ 3. Most results are derived from continued fractions and their matrix representations. 相似文献
2.
Roberta Sinisi Gabriele Candiani Françoise Pecker Matteo Zanda 《Tetrahedron letters》2005,46(38):6515-6518
The racemic α-trifluoromethyl-α-amino-β-sulfone hydroxamates 1 were synthesized by means of a nucleophilic addition of sulfur-stabilized carbanions to a N-Cbz imine of trifluoropyruvate (4). The free amino derivative 1a was the most potent inhibitor of both MMP-3 (stromelysin-1) and MMP-9 (gelatinase-B), showing an IC50 = 14 nM and 1 nM, respectively, and excellent selectivity versus MMP-1 (>5000-fold difference in inhibitory capacity). The N-Me derivative 1b was the most selective for MMP-3 with respect to MMP-9 (62-fold difference). 相似文献
3.
I. W. Ellms S. I. Hauser L. W. Winkler H. Pecker V. Froboese A. T. Stuart F. Malméjac J. Tillmans O. Heublein H. Noll J. M. Kolthoff H. Klut Dietl L. Dede E. Hauser E. M. Chamot D. S. Pratt A. E. Johnson H. Silvester W. Vaubel G. Denigès E. H. Miller S. Rothenfusser M. Bornand L. Rosenthaler V. Jahn A. Dané L. v. Liebermann D. Acel E. B. Phelps H. L. Shoub Escaich H. Berger G. D. Elsdon N. Evers H. W. Brubaker F. W. Bruckmiller 《Analytical and bioanalytical chemistry》1922,61(4-5):196-205
4.
The γ-trifluoromethyl γ-sulfone hydroxamate 1 was synthesized both in racemic and enantiomerically pure forms by means of a thia-Michael reaction of p-methoxythiophenol on achiral and chiral 3,3,3-trifluorocrotonoyl Michael acceptors. The (R)-1 enantiomer was the most potent inhibitor of MMP-3 (stromelysin-1), showing an IC50 = 3.2 nM, as well as the most selective with respect to MMP-9 (65-fold). 相似文献
5.
Alain Pecker 《Comptes Rendus Mecanique》2004,332(9):725-730
The increasing need for probability seismic hazard assessment (PSHA) of critical facilities sometimes leads to unrealistic earthquake scenarios with very high induced ground motions. From a physical standpoint these high motions cannot exist because of the limiting resistance capacity of the soil strata through which the seismic waves travel. A simple analytical model is proposed to bound the maximum ground surface acceleration that any soil deposit can transfer. This model is an extension to non zero ground surface velocity of a previously presented model. To cite this article: A. Pecker, C. R. Mecanique 332 (2004). 相似文献
6.
Alain Pecker 《Comptes Rendus Mecanique》2003,331(10):661-666
The increasing need for probability seismic hazard assessment (PSHA) of critical facilities sometimes leads to unrealistic earthquake scenarios with very high induced ground motions. From a physical standpoint these high motions cannot exist because of the limiting resistance capacity of the soil strata through which the seismic waves travel. A simple analytical model is proposed to estimate a bound to the maximum ground surface acceleration that any soil deposit can transfer. To cite this article: A. Pecker, C. R. Mecanique 331 (2003). 相似文献
7.
N. W. Solotarewa F. Wüst J. Duhr A. L. Doyle W. H. Hadley R. V. Stanford A. E. Sobel H. Yuska J. Cohen J. Wierciski F. Nydahl Pecker G. V. L. N. Murty Moroy und Commission technique permanente de la répression des fraudes 《Fresenius' Journal of Analytical Chemistry》1940,120(3-4):115-117
Ohne Zusammenfassung 相似文献
8.
Daniel Pecker 《Geometriae Dedicata》2012,161(1):323-333
Let D be any elliptic right cylinder. We prove that every type of knot can be realized as the trajectory of a ball in D. This proves a conjecture of Lamm and gives a new proof of a conjecture of Jones and Przytycki. We use Jacobi??s proof of Poncelet??s theorem by means of elliptic functions. 相似文献
9.
T. Jaakkola M. Moles J. P. Vigier J. C. Pecker W. Yourgrau 《Foundations of Physics》1975,5(2):257-269
An analysis of the most recent experimental data shows that the isotropic and universal proportionality of redshift to distance, predicted for all distant objects by the expanding universe model, cannot be regarded as an established fact at the present stage of experimental knowledge. An interpretation of the conflicting data is given in terms of interactions between nonzero-mass photons and light scalar bosons. This leads to a new, static, Einstein-type hierarchical model of the universe, where the cosmological redshift results essentially from a tired-light effect. 相似文献
10.
H. Pecker 《Fresenius' Journal of Analytical Chemistry》1959,166(2):132
Ohne Zusammenfassung 相似文献