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61.
Rangel TB Assreuy AM Pires Ade F Carvalho AU Benevides RG Simões Rda C Silva HC Bezerra MJ Nascimento AS Nascimento KS Nagano CS Sampaio AH Delatorre P Rocha BA Fernandes PM Cavada BS 《Molecules (Basel, Switzerland)》2011,16(6):5087-5103
DwL, a lectin extracted from the seeds of Dioclea wilsonii, is a metalloprotein with strong agglutinating activity against rabbit and ABO erythrocytes, inhibited by glucose and mannose. DwL was purified by affinity chromatography on a Sephadex G-50 column and ion exchange chromatography on a HiTrap SP XL column. SDS-PAGE revealed three electrophoretic bands corresponding to the α (25,634 ± 2 Da), β (12,873 ± 2 Da) and γ (12,779 ± 2 Da) chains. Protein sequencing was done by Tandem Mass Spectrometry. The primary sequence featured 237 amino acids and was highly homologous to other reported Diocleinae lectins. A complete X-ray dataset was collected at 2.0 ? for X-Man-complexed DWL crystals produced by the vapor diffusion method. The crystals were orthorhombic and belonged to the space group I222, with the unit-cell parameters a = 59.6, b = 67.9 and c = 109.0 ?. DWL differed in potency from other ConA-like lectins and was found to induce neutrophil migration in rats, making it particularly useful in structural/functional studies of this class of proteins. 相似文献
62.
J. Espinosa-Garc��a C. Rangel M. Monge-Palacios J. C. Corchado 《Theoretical chemistry accounts》2011,128(4-6):743-755
Based on a previous potential energy surface describing the H?+?CCl4 reaction, a new analytical surface named PES-2010 was developed modifying both the functional form to give it more flexibility, and the calibration process in which exclusively theoretical information was used. Thus, the surface is completely symmetric with respect to the permutation of the four methane chlorine atoms, and no experimental information is used in the process. For the kinetics, the thermal rate constants were calculated using variational transition-state theory with semiclassical transmission coefficients over a wide temperature range, 300?C2,500?K. The theoretical results reproduce the experimental variation with temperature. The influence of the tunneling factor is small, since the abstraction reaction involves the motion of a heavy particle (a chlorine atom) that cannot easily tunnel through the reaction barrier. The coupling between the reaction coordinate and the vibrational modes shows qualitatively that the HCl stretching mode in the products appears vibrationally excited. The dynamics study was performed using quasi-classical trajectory calculations, including corrections to avoid the zero-point energy problem. First, we found that the HCl(????, j??) product mostly appears with small rotational energy and vibrational population inversion. Second, the state-specific scattering distributions show backward scattering, which becomes more noticeable as the HCl(????) vibrational state increases. Unfortunately, no experimental dynamics data are available for the title reaction, but the comparison with the kinematically similar and well-studied H?+?Cl2 reaction shows good agreement, indicative of similar mechanisms. These kinetics and dynamics results seem to indicate that the potential energy surface is adequate to describe this reaction, and the reasonable agreement with experiment lends further confidence to this new surface. 相似文献
63.
64.
We show that holomorphic mappings of bounded type defined on Fréchet spaces extend to the bidual. The relationship between holomorphic mappings of bounded type and of uniformly bounded type is discussed and some algebraic and topological properties of the space of all entire mappings of (uniformly) bounded type are proved, for example a holomorphic version of Schauder's theorem. 相似文献
65.
A neutron personal dosemeter using CR-39 as a detector and hydrogenated materials as proton converters for fast neutron detection plus an air layer for thermal neutron detection is being developed in our laboratory. To increase the CR-39 response to thermal neutrons, the air converter was substituted with Nylon in some dosemeters. Several dosemeters with these two configurations were mounted on a water-filled phantom and exposed under different incidence angles (0, 30 and 60) to: (i) Three ISO neutron sources (241Am–Be, bare 252Cf and moderated 252Cf with Cd shielding), and (ii) two realistic neutron sources (SIGMA and moderated 252Cf) at the IRSN (Cadarache) facilities. The irradiated detectors were electrochemically etched and evaluated in order to determine their dose equivalent response in terms of Hp(10,α). The results obtained are compared to those obtained from Monte Carlo simulations using the MCNPX code. 相似文献
66.
R. H. Rangel 《Heat and Mass Transfer》1991,26(3):153-161
This paper describes an analytical model of heat transfer in a two-dimensional, steady, nonreacting particle-containing channel flow. An idealized gas flow of specified uniform velocity between insulated parallel plates is assumed and the nonvaporizing particles are conceptualized as contained within an thin sheet injected at the symmetry plane. Two dimensionless parameters that affect the solution are described. These are the effective gas diffusivityK and the dimensionless particle number densityP. The linear, coupled differential equations governing the energy exchange between the gas and liquid phases are solved by means of the Green's function technique. This procedure yields a Volterra integral-series equation as the solution of the gas-phase energy equation. A series solution of this integral equation is obtained by the method of successive substitutions and terms up to second order are calculated. 相似文献
67.
Some real moduli spaces can be presented as real hyperbolic space modulo a non-arithmetic group. The whole moduli space is
made from some incommensurable arithmetic pieces, in the spirit of the construction of Gromov and Piatetski-Shapiro. 相似文献
68.
Domingo Chinea 《Rendiconti del Circolo Matematico di Palermo》1985,34(1):89-104
In this paper we start with a brief survey on the theory of Riemannian submersions between almost contact metric manifolds. 相似文献
69.
70.
M. Ińes Mínguez Carlos Romero Joaquín Domingo 《The Journal of the Operational Research Society》1988,39(1):61-70
A goal programming model was used to analyse optimum fertilizer combinations. Under this approach, the fertilizer requirements, instead of being fixed values as in traditional linear programming, are considered targets which may or may not be achieved. A penalty system coupled to the goal programming model makes the specified lower and upper levels of nutrients more flexible and realistic. A simple example is used to expound the model, and then applied to real data to give optimum combinations of fertilizers for sugar beet in Western Andalusia (Spain). 相似文献