14 research outputs found
Quantitative trait loci for sensitivity to ethanol intoxication in a C57BL/6JÂ ĂÂ 129S1/SvImJ inbred mouse cross
Individual variation in sensitivity to acute ethanol (EtOH) challenge is associated with alcohol drinking and is a predictor of alcohol abuse. Previous studies have shown that the C57BL/6J (B6) and 129S1/SvImJ (S1) inbred mouse strains differ in responses on certain measures of acute EtOH intoxication. To gain insight into genetic factors contributing to these differences, we performed quantitative trait locus (QTL) analysis of measures of EtOH-induced ataxia (accelerating rotarod), hypothermia, and loss of righting reflex (LORR) duration in a B6Â ĂÂ S1 F2 population. We confirmed that S1 showed greater EtOH-induced hypothermia (specifically at a high dose) and longer LORR compared to B6. QTL analysis revealed several additive and interacting loci for various phenotypes, as well as examples of genotype interactions with sex. QTLs for different EtOH phenotypes were largely non-overlapping, suggesting separable genetic influences on these behaviors. The most compelling main-effect QTLs were for hypothermia on chromosome 16 and for LORR on chromosomes 4 and 6. Several QTLs overlapped with loci repeatedly linked to EtOH drinking in previous mouse studies. The architecture of the traits we examined was complex but clearly amenable to dissection in future studies. Using integrative genomics strategies, plausible functional and positional candidates may be found. Uncovering candidate genes associated with variation in these phenotypes in this population could ultimately shed light on genetic factors underlying sensitivity to EtOH intoxication and risk for alcoholism in humans
STRENGTH DISTRIBUTIONS IN NEODYMIUM ISOTOPES - A TEST OF COLLECTIVE NUCLEAR-MODELS
Excite states n even N isotopes, up to excitation energies of 3-4 MeV, were investigate in proton- and deuteron-scattering experiments performed with high-energy resolution. More than 300 transitions were studied. For several new excited states spin and parity assignments have been suggested. Reduced transition probabilities were extracted for natural-parity states from 0+ up to 6+. The experimental strength distributions have been compared with the predictions of the interacting boson model (IBM) and of the quasi-particle-phonon model (QPM). The octupole transition probabilities are well described in both models as produced by the fragmentation of the f-boson or of E3 phonons. IBM-sdf calculations seem to account also for the transitions to the low-lying 1- states. Quadrupole and hexadecapole distributions are well described in the QPM. The leading configurations are due to 6-8 low-lying one-phonon states. The two- and three-phonon states play an important role especially in Nd-146. The failure of IBM quadrupole and hexadecapole calculations clearly points out the need of introducing additional bosons lying at high excitation energies. QPM evaluations account also for other features of the experimental data, as the E5 and E6 strength distributions and the isovector components. The limits of the two models are discussed