980 research outputs found
[3]He melting curves in high magnetic fields
Thesis (Ph. D. in Science)--University of Tsukuba, (B), no. 1752, 2001.6.30Includes bibliographical references"[3]" is superscrip
Roles for HLA and KIR polymorphisms in natural killer cell repertoire selection and modulation of effector function
Interactions between killer cell immunoglobulin-like receptors (KIRs) and human leukocyte antigen (HLA) class I ligands regulate the development and response of human natural killer (NK) cells. Natural selection drove an allele-level group A KIR haplotype and the HLA-C1 ligand to unusually high frequency in the Japanese, who provide a particularly informative population for investigating the mechanisms by which KIR and HLA polymorphism influence NK cell repertoire and function. HLA class I ligands increase the frequencies of NK cells expressing cognate KIR, an effect modified by gene dose, KIR polymorphism, and the presence of other cognate ligand–receptor pairs. The five common Japanese KIR3DLI allotypes have distinguishable inhibitory capacity, frequency of cellular expression, and level of cell surface expression as measured by antibody binding. Although KIR haplotypes encoding 3DL1*001 or 3DL1*005, the strongest inhibitors, have no activating KIR, the dominant haplotype encodes a moderate inhibitor, 3DL1*01502, plus functional forms of the activating receptors 2DL4 and 2DS4. In the population, certain combinations of KIR and HLA class I ligand are overrepresented or underrepresented in women, but not men, and thus influence female fitness and survival. These findings show how KIR–HLA interactions shape the genetic and phenotypic KIR repertoires for both individual humans and the population
Specific Heat of Disordered Superfluid He
The specific heat of superfluid He, disordered by a silica aerogel, is
found to have a sharp discontinuity marking the thermodynamic transition to
superfluidity at a temperature reduced from that of bulk He. The
magnitude of the discontinuity is also suppressed. This disorder effect can be
understood from the Ginzburg-Landau theory which takes into account elastic
quasiparticle scattering suppressing both the transition temperature and the
amplitude of the order parameter. We infer that the limiting temperature
dependence of the specific heat is linear at low temperatures in the disordered
superfluid state, consistent with predictions of gapless excitations everywhere
on the Fermi surface.Comment: accpeted for publication in Physical Review Letter
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