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81.
D. A. Komarov I. A. Slepneva V. V. Glupov V. V. Khramtsov 《Applied magnetic resonance》2005,28(3-4):411-419
The generation of reactive oxygen species during oxidation of DOPA (3-(3,4-dihydroxyphenyl-DL-alanine) in haemolymph of insects has been studied by electron paramagnetic resonance with spin traps 5-(diethoxyphosphoryl)-5-methyl-1-pyrroline-N-oxide and 1-hydroxy-3-carboxy-pyrrolidine. The data support the formation of DOPA-derived highly reactive intermediates during melanization in haemolymph of insects. The formation of superoxide has not been detected apparently due to reaction of DOPA with superoxide. The rate constant of the latter reaction was estimated ask≈5·105 M?1.c?1. The formation of DOPA-semiquinone in haemolymph has been measured using spin stabilization ofo-semiquinones by Mg2+. The comparative studies in haemolymph of intact insects and insects infected by fungal infection suggest an important role of DOPA-semiquinone production in the immune status of insects. 相似文献
82.
Problems concerned with the formation of multilayer strained-layer heterostructures by “capillary” liquid-phase epitaxy with
forced hydraulic replacement of the solutions in the growth channel are analyzed. It is shown for short contact times between
the solutions and the crystallization surface that the character of their flow in the channel plays an important role in the
achievement of uniformity in the physical characteristics of the layers grown. Theoretical estimates of the hydrodynamic stability
of solutions moving in narrow channels are performed for several III-V systems. A mathematical model, which permits simulation
of the conditions under which strained-layer heterostructures are fabricated, is developed. It takes into account diffusive
and convective mass transport in the liquid for various flow regimes in the capillary and the displacement of the heterogeneous
equilibria in the system under the influence of elastic stresses.
Zh. Tekh. Fiz. 67, 42–49 (July 1997) 相似文献
83.
A new model for high-energy ion implantation is proposed, based on the use of the Fokker-Planck equation. An efficient algorithm
of the adaptive type is devised for the numerical solution of the problem. A simulation of the implantation of boron in silicon
is carried out for energies ranging from 10 to 100 MeV. Good agreement is obtained with the experimental data and the results
of Monte Carlo simulations.
Zh. Tekh. Fiz. 67, 61–67 (January 1997) 相似文献
84.
V. V. Gribkovskii R. V. Gribkovskii F. F. Komarov G. V. Litvinovich A. P. Novikov 《Journal of Applied Spectroscopy》1990,53(4):1088-1091
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 53, No. 4, pp. 628–632, October 1990. 相似文献
85.
We find a formula for the number of directed 5‐cycles in a tournament in terms of its edge scores and use the formula to find upper and lower bounds on the number of 5‐cycles in any n‐tournament. In particular, we show that the maximum number of 5‐cycles is asymptotically equal to , the expected number 5‐cycles in a random tournament (), with equality (up to order of magnitude) for almost all tournaments. 相似文献
86.
Rosado A Hicks GR Norambuena L Rogachev I Meir S Pourcel L Zouhar J Brown MQ Boirsdore MP Puckrin RS Cutler SR Rojo E Aharoni A Raikhel NV 《Chemistry & biology》2011,18(2):187-197
Sortin1 is a chemical genetic-hit molecule that causes specific mislocalization of plant and yeast-soluble and membrane vacuolar markers. To better understand its mode of action, we designed a Sortin1-hypersensitive screen and identified several Sortin1-hypersensitive and flavonoid-defective mutants. Mechanistically, Sortin1 mimics the effect of the glutathione inhibitor buthionine sulfoximine and alters the vacuolar accumulation of flavonoids, likely blocking their transport through vacuole-localized ABC transporters. Structure-activity relationship studies conducted in Arabidopsis revealed the structural requirements for Sortin1 bioactivity and demonstrated that overlapping Sortin1 substructures can be used to discriminate between vacuolar-flavonoid accumulations and vacuolar-biogenesis defects. We conclude that Sortin1 is a valuable probe for dissecting novel links among flavonoid transport, vacuolar integrity, and the trafficking of vacuolar targeted cargoes in Arabidopsis. 相似文献
87.
Biomimetic strategies which utilise hydrogels have been targeted due to favourable hydrogel characteristics such as the presentation of a large surface area for crystal nucleation within a structured yet responsive scaffold. Chitosan hydrogels were prepared and mineralised using a combined method which involves alternate soaking of the films with precursor solutions, followed by treatment with saturated mineral solution. This method has been shown to be effective for the synthesis of calcium carbonate-chitosan composite materials with tensile strength comparable to nacre. The ratio of organic to inorganic is readily controlled through the presoaking solution concentrations. The ubiquity of this method is shown here with respect to switching out both the anion (CaHPO(4)) and the cation (BaSO(4)). Cation doping is also readily achieved allowing formation of Mg-rich CaCO(3). Poly(acrylic acid) added to (Mg,Ca)CO(3)-chitosan systems induces the formation of two polymorphs (vaterite and calcite) which coexist within the composite material. The mineralised scaffolds were analysed by SEM and powder XRD. The successful mineralisation of chitosan templates with various inorganic compounds shows that this combined approach is widely applicable as a biomimetic approach. 相似文献
88.
A. A. Andreev V. M. Komarov A. V. Charukhchev I. M. Litvinenko K. Yu. Platonov 《Journal of Experimental and Theoretical Physics》2002,94(2):222-227
The parameters of fast particles generated upon the interaction of 1019 W/cm2 laser pulses with solid targets are studied. The spatial and energy parameters of fast ions are investigated. It is found that approximately 1–3% of the laser energy is transformed to the energy of mega-and submegaelectronvolt ions at laser pulse intensities ≥1018 W/cm2. It is shown experimentally that an ion beam is directed perpendicular to the target surface. The analytic and numerical simulations agree with experimental results and predict the propagation of fast electrons in the mirror direction with respect to the incident laser beam and of ions perpendicular to the target. The theoretical calculations are compared with the experimental output and spectra of fast electrons and ions. 相似文献
89.
90.
A generalization of the Goryachev-Chaplygin top, which admits the application of the quantum method of the inverse scattering problem, is constructed. The additional parameter introduced plays the same role as the spin of a node in spin chains.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 164, pp. 134–141 (1987).The authors thank E. K. Skylanin for helpful discussions of the quantum method of the inverse problem. 相似文献