2,214 research outputs found
Magnetic phase transitions in SmCoAsO
Magnetization, x-ray diffraction and specific-heat measurements reveal that
SmCoAsO undergoes three magnetic phase transitions. A ferromagnetic transition
attributed to the Co ions, emerges at TC=57 K with a small saturation moment of
0.15muB/Co. Reorientation of the Co moment to an antiferromagnetic state is
obtained at TN2=45 K. The relative high paramagnetic effective moment Peff=1.57
MuB/Co indicates an itinerant ferromagnetic state of the Co sublattice. The
third magnetic transition at TN1=5 K is observed clearly in the specific-heat
study only. Both magnetic and 57Fe Mossbauer studies show that substitution of
small quantities of Fe for Co was unsuccessful.Comment: 10pages text+Figures: comments welcome ([email protected]
Spin melting and refreezing driven by uniaxial compression on a dipolar hexagonal plate
We investigate freezing characteristics of a finite dipolar hexagonal plate
by the Monte Carlo simulation. The hexagonal plate is cut out from a piled
triangular lattice of three layers with FCC-like (ABCABC) stacking structure.
In the present study an annealing simulation is performed for the dipolar plate
uniaxially compressed in the direction of layer-piling. We find spin melting
and refreezing driven by the uniaxial compression. Each of the melting and
refreezing corresponds one-to-one with a change of the ground states induced by
compression. The freezing temperatures of the ground-state orders differ
significantly from each other, which gives rise to the spin melting and
refreezing of the present interest. We argue that these phenomena are
originated by a finite size effect combined with peculiar anisotropic nature of
the dipole-dipole interaction.Comment: Proceedings of the Highly Frustrated Magnetism (HFM2006) conference.
To appear in a special issue of J. Phys. Condens. Matte
Differential gene expression profile in the small intestines of mice lacking pacemaker interstitial cells of Cajal
BACKGROUND: We previously identified eight known and novel genes differentially expressed in the small intestines of wild type and W/W(V )mice, which have greatly reduced populations of the interstitial cells of Cajal, that are responsible for the generation of electrical slow waves, by using a differential gene display method. METHODS: By using the same method we isolated additional candidate genes that were specifically down- or up-regulated in W/W(V )mice. Novel transcripts were designated as DDWMEST. RESULTS: We isolated seven candidates that were specifically down- or up-regulated in W/W(V )mice. Two novel transcripts, DDWMEST 1 and -91 were increased in both fed and fasted W/W(V )mice. Expression of another five genes was suppressed in W/W(V )mice: ARG2 (Arginase II), ONZIN (encoding leukemia inhibitory factor regulated protein), and three novel transcripts: DDWMEST62, -84, and -100. Together with the previous report, we identified fifteen differentially expressed genes in total in the small intestines of W/W(V )mice. Eight of these genes were reduced in the jejunums of W/W(V )mice compared to age matched wild type mice, whereas the other seven genes showed an increase in expression. Differential expression was the same in fasted and fed animals, suggesting that the differences were independent of the dietetic state of the animal. CONCLUSIONS: Several known and novel genes are differentially expressed in the small intestines of W/W(V )mice. Differential gene comparison might contribute to our understanding of motility disorders associated with the loss of the interstitial cells of Cajal
Bubbling Geometries for Half BPS Wilson lines
We consider the supergravity backgrounds that correspond to supersymmetric
Wilson line operators in the context of AdS/CFT correspondence. We study the
gravitino and dilatino conditions of the IIB supergravity under the appropriate
ansatz, and obtain some necessary conditions for a supergravity background that
preserves the same symmetry as the supersymmetric Wilson lines. The
supergravity solutions are characterized by continuous version of maya
diagrams. This diagram is related to the eigenvalue distribution of the
Gaussian matrix model. We also consider the similar backgrounds of the
11-dimensional supergravity.Comment: 25 pages, 9 figures. v2:typos corrected. v3:added the differential
conditions and comments at the end of section 2. typos correcte
Berry's phase in the multimode Peierls states
It is shown that Berry's phase associated with the adiabatic change of local
variables in the Hamiltonian can be used to characterize the multimode Peierls
state, which has been proposed as a new type of the ground state of the
two-dimensional(2D) systems with the electron-lattice interaction.Comment: 2 pages, 2 figure
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