Dirac equation in spacetimes with torsion and non-metricity

Dirac equation is written in a non-Riemannian spacetime with torsion and non-metricity by lifting the connection from the tangent bundle to the spinor bundle over spacetime. Foldy-Wouthuysen transformation of the Dirac equation in a Schwarzschild background spacetime is considered and it is shown that both the torsion and non-metricity couples to the momentum and spin of a massive, spinning particle. However, the effects are small to be observationally significant.Comment: 12 pages LATEX file, no figures, to appear in Int. J. Mod. Phys.

Negative thermal expansion in the Prussian Blue analog Zn3[Fe(CN)6]2: X-ray diffraction and neutron vibrational studies

The cubic Prussian Blue (PB) analog, Zn3 [Fe(CN)6]2, has been studied by X-ray powder diffraction and inelastic neutron scattering (INS). X-ray data collected at 300 and 84 K revealed negative thermal expansion (NTE) behaviour for this material. The NTE coefficient was found to be -31.1 x 10-6 K-1. The neutron vibrational spectrum for Zn3[Fe(CN)6]2.xH2O, was studied in detail. The INS spectrum showed well-defined, well-separated bands corresponding to the stretching of and deformation modes of the Fe and Zn octahedra, all below 800 cm-1.Comment: 4 pages, 3 figure

Poisson-sigma model for 2D gravity with non-metricity

We present a Poisson-sigma model describing general 2D dilaton gravity with non-metricity, torsion and curvature. It involves three arbitrary functions of the dilaton field, two of which are well-known from metric compatible theories, while the third one characterizes the local strength of non-metricity. As an example we show that alpha' corrections in 2D string theory can generate (target space) non-metricity.Comment: 9 page

Knockdown resistance (kdr)-like mutations in the voltage-gated sodium channel of a malaria vector Anopheles stephensi and PCR assays for their detection

<p>Abstract</p> <p>Background</p> <p>Knockdown resistance (<it>kdr</it>) in insects, resulting from mutation(s) in the voltage-gated sodium channel (vgsc) gene is one of the mechanisms of resistance against DDT and pyrethroid-group of insecticides. The most common mutation(s) associated with knockdown resistance in insects, including anophelines, has been reported to be present at residue Leu1014 in the IIS6 transmembrane segment of the vgsc gene. This study reports the presence of two alternative <it>kdr</it>-like mutations, L1014S and L1014F, at this residue in a major malaria vector <it>Anopheles stephensi </it>and describes new PCR assays for their detection.</p> <p>Methods</p> <p>Part of the vgsc (IIS4-S5 linker-to-IIS6 transmembrane segment) of <it>An. stephensi </it>collected from Alwar (Rajasthan, India) was PCR-amplified from genomic DNA, sequenced and analysed for the presence of deduced amino acid substitution(s).</p> <p>Results</p> <p>Analysis of DNA sequences revealed the presence of two alternative non-synonymous point mutations at L1014 residue in the IIS6 transmembrane segment of vgsc, i.e., T>C mutation on the second position and A>T mutation on the third position of the codon, leading to Leu (TTA)-to-Ser (TCA) and -Phe (TTT) amino acid substitutions, respectively. Polymerase chain reaction (PCR) assays were developed for identification of each of these two point mutations. Genotyping of <it>An. stephensi </it>mosquitoes from Alwar by PCR assays revealed the presence of both mutations, with a high frequency of L1014S. The PCR assays developed for detection of the <it>kdr </it>mutations were specific as confirmed by DNA sequencing of PCR-genotyped samples.</p> <p>Conclusions</p> <p>Two alternative <it>kdr-</it>like mutations, L1014S and L1014F, were detected in <it>An. stephensi </it>with a high allelic frequency of L1014S. The occurrence of L1014S is being reported for the first time in <it>An. stephensi</it>. Two specific PCR assays were developed for detection of two <it>kdr</it>-like mutations in <it>An. stephensi</it>.</p