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31.
The Leishmania P2 proteins have been analyzed as potential tools for the immunodiagnosis of human mucocutaneous and visceral leishmaniasis. Two recombinant Leishmania infantum proteins, rLIP2a and rLip2b, were used. The analysis indicated that the rLiP2a and rLiP2b proteins are recognized by 76% (16 of 21) and 42% (9 of 21), respectively, of sera from patients with mucocutaneous leishmaniasis and by 50% (5 of 10) and 40% (4 of 10), respectively, of sera from patients with visceral leishmaniasis. The Leishmania P2 proteins were engineered to have deletions of particular amino acids from the carboxyl-terminal region in order to avoid cross-reactivity with sera from patients with systemic lupus erythematosus and Chagas' disease, since it is known that this region is the main target of the autoantibodies present in sera from these patients. The results show that while the modified recombinant proteins rLiP2a-Q and rLiP2b-Q, in which the five carboxyl-terminal amino acids had been deleted, maintain the leishmaniasis-specific epitopes, they do not react with sera from patients with autoimmune disease and Chagas' disease. For this reason, and also because the sera from patients with tuberculosis and leprosy, diseases that have to be considered in a differential clinical diagnosis of infectious diseases, do not react with the rLiP2a-Q or rLiP2b-Q protein, we think that the engineered proteins may be considered specific tools for the immunodiagnosis of mucocutaneous and visceral leishmaniasis. 相似文献
32.
33.
Antonio Soto Meca Francisco Alhama López Carlos González Fernández 《Computer Physics Communications》2007,177(9):720-728
The network simulation method, based on the formal equivalence between physical systems and electrical networks, solves numerical problems of relatively mathematical complexity in a versatile, efficient and computationally fast way. In this paper, the method is applied for the first time to the design of a general purpose model for simulating two-dimensional transient density-driven flow and solute transport through porous media, a mathematical model made up by coupled, nonlinear differential equations. Using the Boussinesq approximation and the stream function formulation, the model is used to solve two typical problems related with groundwater flows. Isochlor concentration and stream function curves are presented and successfully compared with those of other authors. Simulation is carried out using the digital computer program Pspice with relatively low computing times. 相似文献
34.
35.
Mélanie Lé‐Magda Eric Dargent Jorge Arturo Soto Puente Alain Guillet Emmanuelle Font Jean‐Marc Saiter 《应用聚合物科学杂志》2013,130(2):786-792
Very long aging times, up to 15,100 h (629 days) at 110°C, were achieved on flame‐retardant printed circuit board laminates commonly used in automotive design. This composite was fabricated from glass fibers embedded in an epoxy resin. Aging was performed in an oven under an air atmosphere at a temperature lower than the glass‐transition temperature. Temperature‐modulated differential scanning calorimetric analysis was used to investigate the influence of such aging on the glass‐transition phenomena. A new amorphous phase appeared during aging. By extending the analysis to samples collected at different thicknesses, we demonstrated the existence of a time‐dependent gradient of the properties. A skin–core structure was evidenced, and this slowed down oxidation and allowed physical aging to occur in the bulk sample. An exponential law described the variations of the glass‐transition of the new external compound. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 786‐792, 2013 相似文献
36.
An efficient finite element (FE) scheme to deal with a class of coupled fluid-solid problems is presented. The main ingredients of such methodology are: an accurate Q1/P0 solid element (trilinear in velocities and constant piecewise-discontinuous pressures); a large deformation plasticity model; an algorithm to deal with material failure, cracking propagation and fragment formation; and a fragment rigidization methodology to avoid the possible numerical instabilities that may produce pieces of material flying away from the main solid body. All the mentioned schemes have been fully parallelized and coupled using a loose-embedded procedure with a well-established and validated computational fluid dynamics (CFD) code (FEFLO). A CSD and a CFD/CSD coupled case are presented and analyzed. 相似文献
37.
A. Ortiz S. Lopez C. Falcony M. Farias L. Cota-Araiza G. Soto 《Journal of Electronic Materials》1990,19(12):1411-1415
Silicon dioxide films have been deposited by Plasma-Enhanced Chemical Vapor Deposition (PECVD) technique using SiCl4 and O2 as reactive materials. Infra-red transmittance, Auger electron spectroscopy analysis, ellipsometry, electrical, and chemical
etch measurements have been used to characterize these films. It is possible to obtain good quality oxides at a substrate
temperature of 200° C using a low flow of reactant gases. High flow of reactant gases results in highly non-homogeneous porous
films. The best oxide films obtained show destructive breakdown at electrical fields above 4 MV/cm and a fixed charge density
of the order of 2.6 × 1011 charges/cm2. 相似文献
38.
Influence of training system on chromatic characteristics and phenolic composition in red wines 总被引:1,自引:0,他引:1
S. Río Segade E. Soto Vázquez E. I. Vázquez Rodríguez J. F. Rego Martínez 《European Food Research and Technology》2009,229(5):763-770
Chromatic characteristics and phenolic composition of red wines elaborated from Sousón and Brancellao grapes (Vitis vinifera L.), whose vines were trained in cordon and Guyot systems, were determined. This comparison was possible because there were
no significant differences between yields for each one. Hue was the only significantly different chromatic parameter for both
training systems and cultivars. In Sousón cultivar, saturation, colour intensity and red percentage were greater for Guyot
system. Sousón cultivar trained in Guyot system and Brancellao cultivar trained in cordon system were characterized by higher
total anthocyanin concentration. However, greater ionization index and flavanols reagent with dimethyl aminocinemaldehyde
were associated with Guyot and cordon systems, respectively, independently on cultivar. Furthermore, gentisic acid, as well
as malvidin-3-glucoside, petunidin-3-acetylglucoside and malvidin-3-caffeoylglucoside in less extension, permitted to differentiate
training systems in both Sousón and Brancellao cultivars. Principal component analysis was also performed for a better understanding
of the differences found. 相似文献
39.
Soto H. Diaz C.A. Topomondzo J. Erasme D. Schares L. Guekos G. 《Photonics Technology Letters, IEEE》2002,14(4):498-500
We demonstrate experimentally a new design for an all-optical AND gate operating in the gigahertz regime. The efficiency of this effect was estimated by measuring the conversion coefficients CTETM/ and CTMTE/ indicating the TE to TM mode conversion and vice versa when the amplifier is perturbed with a wavelength tunable control beam. The all-optical gate here described differ from others developed before using semiconductor optical amplifiers in its ability to operate on nondegenerate input signals and to produce an output signal with an independent wavelength from the wavelengths of the input signals 相似文献
40.
The polarization sensitivity of semiconductor optical amplifiers can be assessed in terms of gain or in terms of induced phase shift. Although the former aspect has received a lot of attention, the latter is rarely mentioned in the literature. Nevertheless, this birefringence leading to a rotation of the lightwave polarization at the output of the device may give rise to some interesting or unwanted effects. An optical control of the birefringence can be applied to wavelength conversion, signal regeneration, all-optical switching or gating. In this letter, the variation of the birefringence with input polarization and input power is measured 相似文献