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The main advantages of the switched reluctance motor are high torque, wide speed range, simple structure and fault tolerance. Because a switched reluctance motor has inherently nonlinear magnetic characteristics and a doubly salient pole structure, a finite-element analysis approach (FEA) is often adopted to obtain accurate magnetic representation. However, the solution time can be large for a FEA simulation if the mesh is detailed and/or many simulations are required. We propose a rapid analytical solution for determining the aligned and unaligned flux linkage using a magnetic circuit model. We present a simple method for obtaining the air-gap permeance for unaligned linkage. The results of our method agree well with FEA solutions. © 2006 IEEE.

The main advantages of the switched reluctance motor are high torque, wide speed range, simple structure and fault tolerance. Because a switched reluctance motor has inherently nonlinear magnetic characteristics and a doubly salient pole structure, a finite-element analysis approach (FEA) is often adopted to obtain accurate magnetic representation. However, the solution time can be large for a FEA simulation if the mesh is detailed and/or many simulations are required. We propose a rapid analytical solution for determining the aligned and unaligned flux linkage using a magnetic circuit model. We present a simple method for obtaining the air-gap permeance for unaligned linkage. The results of our method agree well with FEA solutions. © 2006 IEEE.

The chemokine receptor CXCR4 is the major coreceptor used for cellular entry by T cell- tropic human immunodeficiency virus (HIV)-1 strains, whereas CCR5 is used by macrophage (M)-tropic strains. Here we show that a small-molecule inhibitor, ALX40-4C, inhibits HIV-1 envelope (Env)-mediated membrane fusion and viral entry directly at the level of coreceptor use. ALX40-4C inhibited HIV-1 use of the coreceptor CXCR4 by T- and dual-tropic HIV-1 strains, whereas use of CCR5 by M- and dual-tropic strains was not inhibited. Dual-tropic viruses capable of using both CXCR4 and CCR5 were inhibited by ALX40-4C only when cells expressed CXCR4 alone. ALX40-4C blocked stromal-derived factor (SDF)-1alpha-mediated activation of CXCR4 and binding of the monoclonal antibody 12G5 to cells expressing CXCR4. Overlap of the ALX40-4C binding site with that of 12G5 and SDF implicates direct blocking of Env interactions, rather than downregulation of receptor, as the mechanism of inhibition. Thus, ALX40-4C represents a small-molecule inhibitor of HIV-1 infection that acts directly against a chemokine receptor at the level of Env-mediated membrane fusion.

The chemokine receptor CXCR4 is the major coreceptor used for cellular entry by T cell- tropic human immunodeficiency virus (HIV)-1 strains, whereas CCR5 is used by macrophage (M)-tropic strains. Here we show that a small-molecule inhibitor, ALX40-4C, inhibits HIV-1 envelope (Env)-mediated membrane fusion and viral entry directly at the level of coreceptor use. ALX40-4C inhibited HIV-1 use of the coreceptor CXCR4 by T- and dual-tropic HIV-1 strains, whereas use of CCR5 by M- and dual-tropic strains was not inhibited. Dual-tropic viruses capable of using both CXCR4 and CCR5 were inhibited by ALX40-4C only when cells expressed CXCR4 alone. ALX40-4C blocked stromal-derived factor (SDF)-1alpha-mediated activation of CXCR4 and binding of the monoclonal antibody 12G5 to cells expressing CXCR4. Overlap of the ALX40-4C binding site with that of 12G5 and SDF implicates direct blocking of Env interactions, rather than downregulation of receptor, as the mechanism of inhibition. Thus, ALX40-4C represents a small-molecule inhibitor of HIV-1 infection that acts directly against a chemokine receptor at the level of Env-mediated membrane fusion.