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X‐ray diffraction in a perfect crystal with distorted surface layer is considered on the basis of the recurrence relations for amplitude reflection and transmission coefficients of X‐rays in a multilayer crystal. It is shown that such parameters of a distorted layer as its thickness and change in the interplanar spacing can be determined directly from diffraction curves of different orders.

It is shown that introducing quantum effects using de Broglie-Bohm theory in the canonical formulation of gravity changes the constraint algebra. The new algebra is a clear projection of general coordinate transformations to the spatial and temporal diffeomorphisms. The quantum Einstein equations are manifestly covariant under the above diffeomorphisms.

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A comprehensive simulation capability to describe RTP related issues has been developed. The simulator describes: 1) The radiative heat transfer in 3D with cylindric symmetry by combined zonal-Monte-Carlo method for arbitrary geometry and for various boundary conditions. The spectrum of tungstenhalogen lamp is modeled realistically and the software allows for analysis of multivariable independent lamp control; 2) Conductive heat transfer in the patterned wafer as a function of patterns (3D representation -crucial for stress analysis) and in the chamber walls (important for temperature uniformity from run to run); 3) 3D wafer warpage and thermal stress analysis of the wafer treated as a laminated plate; 4) Electromagnetic wave interaction with the object of a size comparable to the wave length of radiation for multi-layered nonplanar structures including steps and trenches.; 5 ) Evaluation of emissivity of the wafer with deposited films for optical pyrometry. The software has been applied to various situations of which selected subsequent examples demonstrate its capability.A. Radiative Heat Transfer 3D radiative heat transfer in an RTP chamber with arbitrary shape of the chamber geometry, wafer (edge shape), reflecting shields, etc. (Fig.1) has been implemented. A hybrid zonal-MC numerical method is used; specular multiple reflections exchange factors and diffusive reflections view factors are employed. The exchange factors are updated at each time step to account for changing optical properties as a function of wave length, temperature and substrate doping. The model takes into account realistic spectral and temperature dependences of the optical properties of the wafer and chamber walls which may be opaque or semitransparent. In Fig.2 temperature nonuniformity as a function of radial position on the wafer for different time steps for two lamp powerings is shown. Chamber geometry and lamps configuration shown in Fig.1 were used. In both cases steady temperature of the center was 1023 K. During ramp-up, when thermal radiation from the wafer is considerably smaller than from the lamps, the center is colder than the edge due to more intense radiative heating of the edge. As the wafer is heated radiative losses from the wafer edge make the edge cooler than the center (steady state). The temperature has been studied for various lamp, shield ( Fig. 1) and wafer coating configurations. Diffusive reflections are more effective for wafer heating than specular reflections. This fact can be used in designing the chamber surfaces. However, correct data for the angular dependence of the diffusively reflective surfaces are needed. 0 0 Lamparrays 0 0 Qartz window Wafer Fig.1. Schematic sketch of cylindric RTP chamber.

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Missense mutations in the VHL gene during sporadic clear cell renal cell carcinoma were studied to evaluate their localization in relation to functionally important motifs of the VHL protein. Somatic mutations were identified in 124 of 307 samples. All missense mutations in the α-domain were localized in the binding site for elongin C. Substitutions in the β-domain (77%) were found in the HIF-binding site. Five missense mutations were absent in these sites, which illustrates their role in VHL protein formation or suppressor function of other protein cofactors. Mutation c.392A→T (p.N131I) was identified for the first time. Our results hold much promise to estimate the boundaries of functionally important sites in the VHL suppressor gene and contribute to the interpretation of a pathogenic role of mutations in direct DNA diagnostics.