22 research outputs found
Resonances in an external field: the 1+1 dimensional case
Using non-relativistic effective field theory in 1+1 dimensions, we
generalize Luescher's approach for resonances in the presence of an external
field. This generalized approach provides a framework to study the
infinite-volume limit of the form factor of a resonance determined in lattice
simulations.Comment: 13 pages, 2 postscript figure
Matrix elements of unstable states
Using the language of non-relativistic effective Lagrangians, we formulate a
systematic framework for the calculation of resonance matrix elements in
lattice QCD. The generalization of the L\"uscher-Lellouch formula for these
matrix elements is derived. We further discuss in detail the procedure of the
analytic continuation of the resonance matrix elements into the complex energy
plane and investigate the infinite-volume limit
Resonances in a finite volume
International audienceWe review applications of effective field theory methods in a finite volume for the extraction of the characteristics of unstable particles from lattice QCD calculations. In particular, the scalar mesons f0(980),a0(980) are considered. We formulate criteria that distinguish between hadronic molecules and tightly bound quark states, as well as between the ordinary qq̄ and the tetraquark states. Using these criteria will enable one to study the nature of scalar mesons on the lattice. Further, we also formulate a procedure to calculate resonance matrix elements on the lattice by using the background field method
Pseudoexfoliation syndrome-associated genetic variants affect transcription factor binding and alternative splicing of <em>LOXL1</em>.
Although lysyl oxidase-like 1 (LOXL1) is known as the principal genetic risk factor for pseudoexfoliation (PEX) syndrome, a major cause of glaucoma and cardiovascular complications, no functional variants have been identified to date. Here, we conduct a genome-wide association scan on 771 German PEX patients and 1,350 controls, followed by independent testing of associated variants in Italian and Japanese data sets. We focus on a 3.5-kb four-component polymorphic locus positioned spanning introns 1 and 2 of LOXL1 with enhancer-like chromatin features. We find that the rs11638944:C>G transversion exerts a cis-acting effect on the expression levels of LOXL1, mediated by differential binding of the transcription factor RXRα (retinoid X receptor alpha) and by modulating alternative splicing of LOXL1, eventually leading to reduced levels of LOXL1 mRNA in cells and tissues of risk allele carriers. These findings uncover a functional mechanism by which common noncoding variants influence LOXL1 expression