103 research outputs found
Public Policy, Employment, and Welfare in an Efficiency Wage Model
This paper develops an efficiency wage model to highlight public policy for relieving unemployment. For the purposes of relief, we present unemployment benefits, public employment programs and wage subsidies. The results show that unemployment benefits have a negative effect on the employment rate, while public employment and wage subsidies have a positive effect. The impact of these policies on social welfare is also considered.
The Effect of Mortality Salience and Collaborative Experience on Aggression of "Third-Party Victims"
NMR Study of Carrier Doping Effects on Spin Gaps in the Spin Ladder Sr14-xAxCu24O41 (A = Ca, Y, and La)
Rapid and simple determination of histamine-N-methyl transferase activity by high-performance liquid chromatography with UV detection
Molecular phylogeny of the higher and lower taxonomy of the Fusarium genus and differences in the evolutionary histories of multiple genes
<p>Abstract</p> <p>Background</p> <p>Species of the <it>Fusarium </it>genus are important fungi which is associated with health hazards in human and animals. The taxonomy of this genus has been a subject of controversy for many years. Although many researchers have applied molecular phylogenetic analysis to examine the taxonomy of <it>Fusarium </it>species, their phylogenetic relationships remain unclear only few comprehensive phylogenetic analyses of the <it>Fusarium </it>genus and a lack of suitable nucleotides and amino acid substitution rates. A previous stugy with whole genome comparison among <it>Fusairum </it>species revealed the possibility that each gene in <it>Fusarium </it>genomes has a unique evolutionary history, and such gene may bring difficulty to the reconstruction of phylogenetic tree of <it>Fusarium</it>. There is a need not only to check substitution rates of genes but also to perform the exact evaluation of each gene-evolution.</p> <p>Results</p> <p>We performed phylogenetic analyses based on the nucleotide sequences of the rDNA cluster region (rDNA cluster), and the β-tubulin gene (<it>β-tub</it>), the elongation factor 1α gene (<it>EF-1α</it>), and the aminoadipate reductase gene (<it>lys2</it>). Although incongruence of the tree topologies between <it>lys2 </it>and the other genes was detected, all genes supported the classification of <it>Fusarium </it>species into 7 major clades, I to VII. To obtain a reliable phylogeny for <it>Fusarium </it>species, we excluded the <it>lys2 </it>sequences from our dataset, and re-constructed a maximum likelihood (ML) tree based on the combined data of the rDNA cluster, <it>β-tub</it>, and <it>EF-1α</it>. Our ML tree indicated some interesting relationships in the higher and lower taxa of <it>Fusarium </it>species and related genera. Moreover, we observed a novel evolutionary history of <it>lys2</it>. We suggest that the unique tree topologies of <it>lys2 </it>are not due to an analytical artefact, but due to differences in the evolutionary history of genomes caused by positive selection of particular lineages.</p> <p>Conclusion</p> <p>This study showed the reliable species tree of the higher and lower taxonomy in the lineage of the <it>Fusarium </it>genus. Our ML tree clearly indicated 7 major clades within the <it>Fusarium </it>genus. Furthermore, this study reported differences in the evolutionary histories among multiple genes within this genus for the first time.</p
Proinflammatory role of amphiregulin, an epidermal growth factor family member whose expression is augmented in rheumatoid arthritis patients
Quasiparticle excitation in and around the vortex core of underdoped YBa_2Cu_4O_8 studied by site-selective NMR
We report a site-selective ^{17}O spin-lattice relaxation rate T_1^{-1} in
the vortex state of underdoped YBa_2Cu_4O_8. We found that T_1^{-1} at the
planar sites exhibits an unusual nonmonotonic NMR frequency dependence. In the
region well outside the vortex core, T_1^{-1} cannot be simply explained by the
density of states of the Doppler-shifted quasiparticles in the d-wave
superconductor. Based on T_1^{-1} in the vortex core region, we establish
strong evidence that the local density of states within the vortex core is
strongly reduced.Comment: 5 pages, 3 figure
Charged Vortices in High Temperature Superconductors Probed by NMR
We report a first experimental evidence that a vortex in the high temperature
superconductors (HTSC) traps a finite electric charge from the high resolution
measurements of the nuclear quadrupole frequencies. In slightly overdoped
YBa_2Cu_3O_7 the vortex is negatively charged by trapping electrons, while in
underdoped YBa_2Cu_4O_8 it is positively charged by expelling electrons. The
sign of the trapped charge is opposite to the sign predicted by the
conventional BCS theory. Moreover, in both materials, the deviation of the
magnitude of the charge from the theory is also significant. These unexpected
features can be attributed to the novel electronic structure of the vortex in
HTSC.Comment: 6 pages, 7 figures, to be published in Phys Rev.
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