7 research outputs found
Pairing and continuum effects on low-frequency quadrupole vibrations in deformed Mg isotopes close to the neutron drip line
Low-frequency quadrupole vibrational modes in deformed Mg close
to the neutron drip line are studied by means of the quasiparticle-random-phase
approximation based on the coordinate-space Hartree-Fock-Bogoliubov formalism.
Strongly collective and excitation modes carrying 10-20
Weisskopf units in the intrinsic isoscalar quadrupole transition strengths are
obtained at about 3 MeV. There are two reasons for the enhancement of the
transition strengths. First, the quasiparticle wave functions generating these
modes possess spatially very extended structure. The asymptotic selection rules
characterizing the and vibrations in stable deformed nuclei
are thus strongly violated. Second, the dynamic pairing effects act strongly to
enhance the collectivity of these modes. It is suggested that the lowest
collective mode is a particularly sensitive indicator of the
nature of pairing correlations in deformed nuclei close to the neutron drip
line.Comment: 23 pages including 11 figures and 8 tables. Submitted to NP
Synthesis of both enantiomers of akolactone B and (+)-ancepsenolide
The syntheses of (+)- and (−)-akolactone B and (+)-ancepsenolide were accomplished using a Pd-catalyzed carbonylation. As to the absolute configuration of akolactone B, making a comparison of the specific rotation of both enantiomers of synthetic akolactone B and the natural compound suggests that the absolute configuration at the 4-position of akolactone B is (R).ArticleTETRAHEDRON-ASYMMETRY. 25(20-21):1367-1371 (2014)journal articl
Mutations Found in the Asc1 Gene That Confer Susceptibility to the AAL-Toxin in Ancestral Tomatoes from Peru and Mexico
Tomato susceptibility/resistance to stem canker disease caused by Alternaria alternata f. sp. lycopersici and its pathogenic factor AAL-toxin is determined by the presence of the Asc1 gene. Several cultivars of commercial tomato (Solanum lycopersicum var. lycopersicum, SLL) are reported to have a mutation in Asc1, resulting in their susceptibility to AAL-toxin. We evaluated 119 ancestral tomato accessions including S. pimpinellifolium (SP), S. lycopersicum var. cerasiforme (SLC) and S. lycopersicum var. lycopersicum “jitomate criollo” (SLJ) for AAL-toxin susceptibility. Three accessions, SP PER018805, SLC PER018894, and SLJ M5-3, were susceptible to AAL-toxin. SLC PER018894 and SLJ M5-3 had a two-nucleotide deletion (nt 854_855del) in Asc1 identical to that found in SLL cv. Aichi-first. Another mutation (nt 931_932insT) that may confer AAL-toxin susceptibility was identified in SP PER018805. In the phylogenetic tree based on the 18 COSII sequences, a clade (S3) is composed of SP, including the AAL-toxin susceptible PER018805, and SLC. AAL-toxin susceptible SLC PER018894 and SLJ M5-3 were in Clade S2 with SLL cultivars. As SLC is thought to be the ancestor of SLL, and SLJ is an intermediate tomato between SLC and SLL, Asc1s with/without the mutation seem to have been inherited throughout the history of tomato domestication and breeding