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71.
Tobias I Swigon D Coleman BD 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》2000,61(1):747-758
Results are presented in the theory of the elastic rod model for DNA, among which are criteria enabling one to determine whether a calculated equilibrium configuration of a DNA segment is stable in the sense that it gives a local minimum to the sum of the segment's elastic energy and the potential of forces acting on it. The derived stability criteria are applicable to plasmids and to linear segments subject to strong anchoring end conditions. Their utility is illustrated with an example from the theory of configurations of the extranucleosomal loop of a DNA miniplasmid in a mononucleosome, with emphasis placed on the influence that nicking and ligation on one hand, and changes in the ratio of elastic coefficients on the other, have on the stability of equilibrium configurations. In that example, the configurations studied are calculated using an extension of the method of explicit solutions to cases in which the elastic rod modeling a DNA segment is considered impenetrable, and hence excluded volume effects and forces arising from self-contact are taken into account. 相似文献
72.
John D. Coleman 《Fiber and Integrated Optics》1990,9(4):303-311
This paper details the information SWBT has obtained from our ongoing Fiber-to-the-Home (FTTH) and Fiber-to-the-Curb (FTTC) fiber field trials. The developing architectures, technologies, and Optical Network Unit (ONU) powering strategies are discussed as they impact the development of an SWBT fiber deployment approach for the local loop. 相似文献
73.
74.
It has been shown elsewhere that in the case of relativistic theories, there exists a local differential-topological criterion which distinguishes sharply between geometry and forces. This criterion is also epistemologically effective. In this paper, we explain why this local criterion fails in the pre-relativistic context. The principal reason for the difference is that the causal structure is determined by a quadratic function of 3-velocity in the relativistic case and by a linear function of 3-velocity in the pre-relativistic case. 相似文献
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77.
K. G. Schulz G. Kunisch H. Siegfried R. Otto A. Götz S. Rosier B. Lampe R. Deplanaque F. Eckhardt D. A. Coleman S. R. Snider J. De Clerk F. Tombeur Olli Ant-Wuorinen und F. M. Wieninger 《Fresenius' Journal of Analytical Chemistry》1937,109(1-2):60-63
Ohne Zusammenfassung 相似文献
78.
The matrix isolation technique, combined with infrared spectroscopy and twin jet codeposition, has been used to characterize intermediates formed during the ozonolysis of 2,3-dimethyl-2-butene (DMB). Absorptions of early intermediates in the twin jet experiments grew up to 200% upon annealing to 35 K. A number of these absorptions have been assigned to the elusive Criegee intermediate (CI) and secondary ozonide (SOZ) of DMB, transient species not previously observed for this system. Also observed was the primary ozonide (POZ), in agreement with earlier studies. The wavelength dependence of the photodestruction of these product bands was explored with irradiation from λ ≥ 220 to ≥580 nm. Merged jet (flow reactor) experiments generated "late" stable oxidation products of DMB. A recently developed concentric jet method was also utilized to increase yields and monitor the concentration of intermediates and products formed at different times by varying the length of mixing distance (d = 0 to -11 cm) before reaching the cold cell for spectroscopic detection. Identification of intermediates formed during the ozonolysis of DMB was further supported by (18)O and scrambled (16,18)O isotopic labeling experiments as well as theoretical density functional calculations at the B3LYP/6-311++G(d,2p) level. 相似文献
79.
Adamson P Auty DJ Ayres DS Backhouse C Barr G Bishai M Blake A Bock GJ Boehnlein DJ Bogert D Cavanaugh S Cherdack D Childress S Coelho JA Coleman SJ Corwin L Cronin-Hennessy D Danko IZ de Jong JK Devenish NE Diwan MV Dorman M Escobar CO Evans JJ Falk E Feldman GJ Frohne MV Gallagher HR Gomes RA Goodman MC Gouffon P Graf N Gran R Grant N Grzelak K Habig A Harris D Hartnell J Hatcher R Himmel A Holin A Huang X Hylen J Ilic J Irwin GM Isvan Z Jaffe DE James C Jensen D Kafka T Kasahara SM Koizumi G 《Physical review letters》2011,107(1):011802
Results are reported from a search for active to sterile neutrino oscillations in the MINOS long-baseline experiment, based on the observation of neutral-current neutrino interactions, from an exposure to the NuMI neutrino beam of 7.07×10(20) protons on target. A total of 802 neutral-current event candidates is observed in the Far Detector, compared to an expected number of 754 ± 28(stat) ± 37(syst) for oscillations among three active flavors. The fraction f(s) of disappearing ν(μ) that may transition to ν(s) is found to be less than 22% at the 90% C.L. 相似文献
80.
Adamson P Andreopoulos C Armstrong R Auty DJ Ayres DS Backhouse C Barr G Bishai M Blake A Bock GJ Boehnlein DJ Bogert D Cavanaugh S Cherdack D Childress S Choudhary BC Coelho JA Coleman SJ Corwin L Cronin-Hennessy D Danko IZ de Jong JK Devenish NE Diwan MV Dorman M Escobar CO Evans JJ Falk E Feldman GJ Frohne MV Gallagher HR Gomes RA Goodman MC Gouffon P Graf N Gran R Grant N Grzelak K Habig A Harris D Hartnell J Hatcher R Himmel A Holin A Huang X Hylen J Ilic J Irwin GM Isvan Z Jaffe DE 《Physical review letters》2011,106(18):181801
Measurements of neutrino oscillations using the disappearance of muon neutrinos from the Fermilab NuMI neutrino beam as observed by the two MINOS detectors are reported. New analysis methods have been applied to an enlarged data sample from an exposure of 7.25×10(20) protons on target. A fit to neutrino oscillations yields values of |Δm(2)|=(2.32(-0.08)(+0.12))×10(-3) eV(2) for the atmospheric mass splitting and sin(2)(2θ)>0.90 (90% C.L.) for the mixing angle. Pure neutrino decay and quantum decoherence hypotheses are excluded at 7 and 9 standard deviations, respectively. 相似文献