31 research outputs found
Novel Analytical Calculation Method for the Non-Linear Ψ -i- Characteristic of Switched-Reluctance-Machines in Arbitrary Rotor Positions
Abstract The non-linear Ψ -i-characteristic is crucial for the design of switched reluctance machines. Known analytical calculations are based on complex models of the magnetic circuit or on functions needing a fitting procedure (using measured or FEM-calculated data). In this paper, a method is presented that requires only very few input data, which can be deduced easily from the geometry of the machine. Comparisons with measured data show an acceptable correlation for arbitrary rotor positions, qualifying this method to be used in the design stage of new drives
Natural killer cell-mediated cytotoxicity shapes the clonal evolution of B-cell leukemia
The term cancer immunoediting describes the dual role by which the immune system can suppress and promote tumor growth and is divided into three phases: elimination, equilibrium, and escape. The role of NK cells has mainly been attributed to the elimination phase. Here, we show that NK cells play a role in all three phases of cancer immunoediting. Extended co-culturing of DNA-barcoded mouse BCR/ABLp185+ B-cell acute lymphoblastic leukemia (B-ALL) cells with NK cells allowed for a quantitative measure of NK cell–mediated immunoediting. Although most tumor cell clones were efficiently eliminated by NK cells, a certain fraction of tumor cells harbored an intrinsic primary resistance. Furthermore, DNA barcoding revealed tumor cell clones with secondary resistance, which stochastically acquired resistance to NK cells. NK cell–mediated cytotoxicity put a selective pressure on B-ALL cells, which led to an outgrowth of primary and secondary resistant tumor cell clones, which were characterized by an IFNγ signature. Besides well-known regulators of immune evasion, our analysis of NK cell–resistant tumor cells revealed the upregulation of genes, including lymphocyte antigen 6 complex, locus A (Ly6a), which we found to promote leukemic cell resistance to NK cells. Translation of our findings to the human system showed that high expression of LY6E on tumor cells impaired their physical interaction with NK cells and led to worse prognosis in patients with leukemia. Our results demonstrate that tumor cells are actively edited by NK cells during the equilibrium phase and use different avenues to escape NK cell–mediated eradication.Immunobiology of allogeneic stem cell transplantation, transfusion medicine and immunotherapy of hematological disease
Novel Analytical Calculation Method for the Non-Linear ψ-i-Characteristic of Switched-Reluctance-Machines in the Aligned Rotor Position
A survey of different analytical methods to calculate the non-linear Ψ-i-characteristic of switched-reluctance-machines
Novel analytical calculation method for the non-linear Ѱ -і- characteristic of switched-reluctance-machines in arbitrary rotor positions
Die elektrische Antriebstechnologie der BMW Group./The Electrical Powertrain Technology of BMW Group.
Causal simplicity and (maximal) null pseudoconvexity
We consider pseudoconvexity properties in Lorentzian and Riemannian manifolds and their relationship in static spacetimes. We provide an example of a causally continuous and maximal null pseudoconvex spacetime that fails to be causally simple. Its Riemannian factor provides an analogous example of a manifold that is minimally pseudoconvex, but fails to be convex
