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1.
The adsorption isotherm data of R- and S-1-indanol and of their racemic mixture on cellulose tribenzoate were measured by frontal analysis. These experimental data were fitted to the single-component and the modified competitive Bilangmuir isotherms. The overloaded elution profiles of bands of the pure enantiomers and of the racemic mixture were calculated for different sample sizes, using the best competitive isotherm model and the General Rate Model of chromatography coupled with the generalized Maxwell-Stefan equation that describes the surface diffusion flux. The calculated and the experimental profiles were found to be in excellent agreement in all cases. The parameters of the model of the mass transfer kinetics were derived from the band profiles obtained for the pure enantiomers. The same values of these parameters give an excellent prediction of the profiles of multicomponent bands. The new model described here allows a satisfactory interpretation of the competitive mass transfer kinetics.  相似文献   
2.
目的评估免疫细胞素Hu14.18-IL-2对黑色素瘤病人体内免疫作用。方法33位黑色素瘤病人用一种人源化抗神经节苷脂GD-2的单抗与IL-2融合的免疫细胞素进行治疗,按每天0.8、1.6、3.2、4.8、6.0、7.5 mg/m2静脉滴注,连续3 d为一疗程,病情稳定或缓解后,在第5周接受第2疗程治疗。观察病人外周血单核淋巴细胞抗体依赖的细胞毒性、自然杀伤细胞活性、IL-2的体外增殖以及IL-2可溶性受体的变化。结果Hu14.18-IL-2能诱导病人淋巴细胞的吞噬作用,增强外周血中自然杀伤细胞的杀伤能力和数目,使血清中IL-2受体复合体的可溶性受体α链水平上升。结论免疫细胞素Hu14.18-IL-2对黑色素瘤病人具有免疫激活作用。  相似文献   
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4.
Reconstructing boundaries along material interfaces from volume fractions is a difficult problem, especially because the under‐resolved nature of the input data allows for many correct interpretations. Worse, algorithms widely accepted as appropriate for simulation are inappropriate for visualization. In this paper, we describe a new algorithm that is specifically intended for reconstructing material interfaces for visualization and analysis requirements. The algorithm performs well with respect to memory footprint and execution time, has desirable properties in various accuracy metrics, and also produces smooth surfaces with few artifacts, even when faced with more than two materials per cell.  相似文献   
5.
The objectives of an organization in combination with the formal policy together underpin the strategic direction that any organization will take. We all know that security begins with policy – in other words the rules of play. If policy is sound then the appropriate security measures can be implemented to protect the activities required to achieve the stated objectives as well as maintain the information assurance requirements – availability, integrity, authentication, confidentiality and non-repudiation.  相似文献   
6.
Light use efficiency (LUE) is an important variable characterizing plant eco-physiological functions and refers to the efficiency at which absorbed solar radiation is converted into photosynthates. The estimation of LUE at regional to global scales would be a significant advantage for global carbon cycle research. Traditional methods for canopy level LUE determination require meteorological inputs which cannot be easily obtained by remote sensing. Here we propose a new algorithm that incorporates the enhanced vegetation index (EVI) and a modified form of land surface temperature (Tm) for the estimation of monthly forest LUE based on Moderate Resolution Imaging Spectroradiometer (MODIS) imagery. Results demonstrate that a model based on EVI × Tm parameterized from ten forest sites can provide reasonable estimates of monthly LUE for temperate and boreal forest ecosystems in North America with an R2 of 0.51 (p < 0.001) for the overall dataset. The regression coefficients (a, b) of the LUE–EVI × Tm correlation for these ten sites have been found to be closely correlated with the average EVI (EVI_ave, R2 = 0.68, p = 0.003) and the minimum land surface temperature (LST_min, R2 = 0.81, p = 0.009), providing a possible approach for model calibration. The calibrated model shows comparably good estimates of LUE for another ten independent forest ecosystems with an overall root mean square error (RMSE) of 0.055 g C per mol photosynthetically active radiation. These results are especially important for the evergreen species due to their limited variability in canopy greenness. The usefulness of this new LUE algorithm is further validated for the estimation of gross primary production (GPP) at these sites with an RMSE of 37.6 g C m? 2 month? 1 for all observations, which reflects a 28% improvement over the standard MODIS GPP products. These analyses should be helpful in the further development of ecosystem remote sensing methods and improving our understanding of the responses of various ecosystems to climate change.  相似文献   
7.
The frequency of erythrocyturia in children with diagnosed food allergy was evaluated. The analysed clinical and immunological allergic process indicators and one year's observation confirm the allergic background of erythrocyturia in 2.6% of the examined group. There are indications for an elimination diet and the application of anti-allergic treatment in the above cases.  相似文献   
8.
The intraparticle diffusion coefficient was measured using a method based on the fitting of a set of experimental chromatographic profiles to the lumped pore diffusion model. For this purpose, both the analytical solution of the model in the Laplace domain and a numerical method were used. There was an excellent agreement between the results given by the two methods. These results are compared to those obtained by moment analysis of the same set of chromatographic profiles and by the determination of the intraparticle diffusion coefficient from the second central moment of these bands. Nearly identical results were obtained with these two independent methods. The values of the intraparticle diffusion coefficient, De, for rubrene in pure methanol was found to be by the modeling method and by the moment analysis method. These values increase with increasing water concentration, to 1.10×10−6 and , respectively, in a methanol/water solution and to 1.63×10−6 and , respectively, in a solution.These results confirm the validity and the consistency of the lumped pore model and the moment analysis theory. They show that both approaches describe correctly the mass transfer kinetics in the particles of packing material during the chromatographic process. Systematic determinations of the intraparticle diffusion coefficient can now be undertaken and the influence of various experimental parameters on this important property of packing materials can be investigated.  相似文献   
9.
Compared the effects of signaled and unsignaled shock on the pituitary-adrenal response of 68 male Long-Evans hooded rats. In Exp I, exposure to the 2 procedures yielded no difference in plasma corticosterone levels. In Exp II, the addition of a food-reinforced leverpressing baseline produced conditioned suppression in the signaled condition but no group difference in steroid values. To guard against steroid elevations produced by exposure to shock, blood samples in Exp III were obtained during brief test sessions prior to the occurrence of shock. The procedure resulted in a significant elevation in the steroid levels of the signaled shock group. In Exp IV, a within-Ss sampling procedure revealed that disparate group steroid values obtained earlier in the session had converged by the end of the test session. The final experiment produced the original failure to obtain a steroid difference due to predictability in the absence of a behavioral baseline. Results suggest that (a) the effects of predictability are largely seen in the temporal pattern of steroid elevations and not in their terminal values, (b) the effects of predictability on steroids are modulated by the availability of control, and (c) control is not confined to the stimulus that is being predicted. (36 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Texture mapping is a method commonly used to increase the visual complexity of computer generated images while maintaining simplicity in the underlying geometric models. Texture maps are generally defined in two dimensional space; thus, a primary problem when applying textures to objects is determining a mapping transformation from the three dimensional space of the object to the two dimensional space of the map. A method for mapping complex polygonal geometries is presented. The algorithmunfolds the object polygon by polygon and projects the texture map onto the resulting two dimensional geometry. Enhancements to the basic unfolding algorithm either (1) control the location of map distorition introduced at areas of severe curvature or (2) average distortions over a larger area.  相似文献   
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