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31.
Calmodulin (CaM) has been reported to have affinity for the estrogen receptor (ER). Observations reported here reveal a direct physical interaction between purified CaM and ER. This direct ER-CaM interaction may be an initial event preceding the assembly of ER plus auxiliary proteins into the active ER complex with its DNA motif, the estrogen response element. We demonstrate that CaM is an integral component of this complex by using a system reconstituted from purified ER and nuclear extract from ER-negative breast cancer cells and also with ER-depleted nuclear extract of an ER-positive breast cancer cell line. Although CaM is essential for formation of this complex, it is not sufficient, suggesting roles also of auxiliary proteins. CaM also is functionally required for activation of an ER-responsive promoter, in the 17beta-estradiol-ER pathway of hormone action and regulation of 17beta-estradiol-responsive gene expression that is associated with proliferation of mammary epithelial cells.  相似文献   
32.
33.
Water Resources Management - Reference evapotranspiration (ET0) is a crucial element for deriving irrigation scheduling of major crops. Thus, precise projection of ET0 is essential for better...  相似文献   
34.
It is shown that if the root-mean-square of the gradient of the phase fluctuation of either of the components exceeds the corresponding inverse of the coherence length or if the chemical potential exceeds 1 0 or 2 0 , where is the volume integrals of the interaction function between the components, and 1 0 , 2 0 are the densities of the two components, the mixture of two rotating superfluids has an instability.  相似文献   
35.
The Journal of Supercomputing - In this article, the authors suggested a rotation-invariant local binary pattern-based weighted generalized closest neighbor (RILBP-WGCN) method for HSI...  相似文献   
36.
Neural Computing and Applications - Preserving red-chili quality is of utmost importance in which the authorities demand quality techniques to detect, classify, and prevent it from impurities. For...  相似文献   
37.
Microsystem Technologies - Single-Walled Carbon Nanotubes (SWCNTs) are widely used as potential carriers in drug delivery systems. The objective of this work was to observe the effects of pristine,...  相似文献   
38.
A mathematical model for the transient heat flow analysis in arc-welding processes is proposed, based on a unique set of boundary conditions. The model attempts to make use of the relative advantages of analytical as well as numerical techniques in order to reduce the problem size for providing a quicker solution without sacrificing the accuracy of prediction. The variation of thermo-physical properties with temperature has been incorporated into the model to improve the thermal analysis in the weld and heat-affected zones. The model has been evaluated using a five-point explicit finite difference method for analysing the welding heat flow in thin plates of two different geometric configurations. The temperature distribution closer to the heat source, primarily in the weld zone and the heat-affected zones, are predicted by the numerical technique. The thermal characteristics beyond the heat-affected zone are amenable to standard analytical techniques. The behaviour of the boundary condition in the model has been investigated in detail.Nomenclature q Rate of heat per unit thickness (Wm–1) - d Plate thickness (m) - v Velocity of source (m s–1) - t Time (s) - T Temperature value at the desired point (K) - T 0 Initial temperature (K) - K Thermal conductivity (W m–1 K–1) - Density (kg m–3) - c p Specific heat (J kg–1 K–1) - Thermal diffusivity (m2 s–1) - n - Distance of point considered from the source (=x–vt) (m) - K 0 Modified Bessel function of second kind and zero order - r Radial distance from the source (r=(x 2+y 2)1/2) (m) - Model width (m) - a Plate width (m) - Distance from the source =(2+4 ×10–4)1/2 (m) - n   相似文献   
39.
Multiprocessor systems which afford a high degree of parallelism are used in a variety of applications. The extremely stringent reliability requirement has made the provision of fault-tolerance an important aspect in the design of such systems. This paper presents a review of the various approaches towards tolerating hardware faults in multiprocessor systems. It emphasizes the basic concepts of fault tolerant design and the various problems to be taken care of by the designer. An indepth survey of the various models, techniques and methods for fault diagnosis is given. Further, we consider the strategies for fault-tolerance in specialized multiprocessor architectures which have the ability of dynamic reconfiguration and are suited tovlsi implementation. An analysis of the state-of-the-art is given which points out the major aspects of fault-tolerance in such architectures.  相似文献   
40.
Silicon - In the present report, a photonic crystal based micro-ring resonator (MRR) structure is proposed which is very compact in size and has very fast response and is employed for temperature...  相似文献   
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