427 research outputs found
Monte Carlo Study of Relaxor Systems: A Minimum Model for Pb(InNb)O}
We examine a simple model for Pb(InNb)O (PIN), which
includes both long-range dipole-dipole interaction and random local anisotropy.
A improved algorithm optimized for long-range interaction has been applied for
efficient large-scale Monte Carlo simulation. We demonstrate that the phase
diagram of PIN is qualitatively reproduced by this minimum model. Some
properties characteristic of relaxors such as nano-scale domain formation, slow
dynamics and dispersive dielectric responses are also examined.Comment: 5 pages, 4 figure
Dual structures in PZN-xPT ferroelectric relaxors
We performed x-ray diffraction studies on a series of
(1-)Pb(ZnNb)O-PbTiO (PZN-PT) single crystals
with different incident photon energies, and therefore different penetration
depths. Our results show that outer-layers of to 50 m thick are
present in all samples. The structure of those outer-layers is different from
that of the inside of the crystals, by having much greater (rhombohedral)
distortions. With increasing , rhombohedral-type lattice distortions
develop, both in the outer-layer and the inside.Comment: submitted to Appl. Phys. Let
Serum Levels of Testosterone in Patients with Poly-cythemia Vera
Abstract Despite its association with vascular events such as myocardial and cerebral infarction, polycythemia vera (PV) is characterized by low serum total cholesterol levels. Because several sex hormones are derived from cholesterol, statins may induce hypogodanism in male patients. Therefore, we assessed the relationship between serum total cholesterol and sex hormone levels according to gender. Medical records of 41 patients with erythrocytosis (hemoglobin concentrations: men >18.5 g/dL; women >16.5 g/dL) collected between August 2005 and December 2014 were reviewed for patient age, and gender, as well as clinical hematology, biochemistry, and endocrinology laboratory findings. Serum levels of testosterone were lower in men with PV than in patients with reactive erythrocytosis (RE) (PV: 385 ± 78 ng/mL versus RE: 529 ± 46 ng/mL). However, serum levels of testosterone in women with PV were comparable to those in patients in the nonerythrocytic group (PV: 20.5 ± 3.5 ng/mL versus non-erythrocytic group: 21.0 ± 4.3 ng/mL). Serum levels of testosterone were not related to serum levels of cholesterol. Therefore, we speculated that lower testosterone levels were not due to lower serum levels of cholesterol, a known adverse effect of statin. In conclusion, we report for the first time that serum levels of testosterone were lower in male PV patients than in those with RE; however, serum levels of testosterone in female patients with PV were not lower
Resonant inelastic x-ray scattering study of hole-doped manganites La1-xSrxMnO3 (x=0.2 and 0.4)
Electronic excitations near the Fermi energy in the hole doped manganese
oxides (La1-xSrxMnO3, x=0.2 and 0.4) have been elucidated by using the resonant
inelastic x-ray scattering (RIXS) method. A doping effect in the strongly
correlated electron systems has been observed for the first time. The
scattering spectra show that a salient peak appears in low energies indicating
the persistence of the Mott gap. At the same time, the energy gap is partly
filled by doping holes and the energy of the spectral weight shifts toward
lower energies. The excitation spectra show little change in the momentum space
as is in undoped LaMnO3, but the scattering intensities in the low energy
excitations of x=0.2 are anisotropic as well as temperature dependent, which
indicates a reminiscence of the orbital nature
NâSubstituted Nipecotic Acids as (S )âSNAPâ5114 Analogues with Modified Lipophilic Domains
Potential mGAT4 inhibitors derived from the lead substance (S )âSNAPâ5114 have been synthesized and characterized for their inhibitory potency. Variations from the parent compound included the substitution of one of its aromatic 4âmethoxy and 4âmethoxyphenyl groups, respectively, with a more polar moiety, including a carboxylic acid, alcohol, nitrile, carboxamide, sulfonamide, aldehyde or ketone function, or amino acid partial structures. Furthermore, it was investigated how the substitution of more than one of the aromatic 4âmethoxy groups affects the potency and selectivity of the resulting compounds. Among the synthesized test substances (S )â1â{2â[(4âformylphenyl)bis(4âmethoxyphenyl)âmethoxy]ethyl}piperidineâ3âcarboxylic acid, that features a carbaldehyde function in place of one of the aromatic 4âmethoxy moieties of (S )âSNAPâ5114, was found to have a pIC50 value of 5.89±0.07, hence constituting a slightly more potent mGAT4 inhibitor than the parent substance while showing comparable subtype selectivity
An epidemiological study on anemia among institutionalized people with intellectual and/or motor disability with special reference to its frequency, severity and predictors
BACKGROUND: To examine the type, frequency, severity, and predictors of anemia and its relationship with co-morbid conditions among institutionalized people with intellectual and/or motor disability. METHODS: We conducted a cross-sectional study at a public facility for people with intellectual and/or motor disability in Ibaraki prefecture, Japan. Health checkup data obtained in 2001 from 477 people with intellectual disability (male: 286, average age 40.6 ± 12.3; female: 191, average age 45.1 ± 11.6) were retrospectively reviewed. RESULTS: The prevalence of anemia among male participants was higher than in female participants for each disability category (intellectual disability, 41.1%, 4.2%; cerebral palsy, 37.5%, 4.8%; Down's syndrome, 15.0%, 0%; severe motor and intellectual disabilities, 61.9%, 16.7%). Most participants with anemia (93.8 â 100%) showed a normocytic normochromic anemia pattern. Multivariate analysis revealed that factors related to an increase in frequency included sex (male), low body mass index (BMI), use of anticonvulsants or major tranquilizers, and a high zinc sulfate turbidity test (ZTT) value. No clinically diagnosed co-morbid condition was found to be related to the presence of anemia. CONCLUSION: A high frequency of mild normocytic normochromic anemia in institutionalized people with intellectual and/or motor disability was observed, particularly among males. Medications and chronic inflammation may increase the risk of anemia
Orthorhombic versus monoclinic symmetry of the charge-ordered state of NaV2O5
High-resolution X-ray diffraction data show that the low-temperature
superstructure of alpha-NaV2O5 has an F-centered orthorhombic 2a x 2b x 4c
superlattice. A structure model is proposed, that is characterized by layers
with zigzag charge order on all ladders and stacking disorder, such that the
averaged structure has space group Fmm2. This model is in accordance with both
X-ray scattering and NMR data. Variations in the stacking order and disorder
offer an explanation for the recently observed devils staircase of the
superlattice period along c.Comment: REVTEX, 4 pages including 2 figures, shortened, submitted to PR
X-ray anomalous scattering investigations on the charge order in -NaVO
Anomalous x-ray diffraction studies show that the charge ordering in
-NaVO is of zig-zag type in all vanadium ladders. We
have found that there are two models of the stacking of layers along
\emph{c-}direction, each of them consisting of 2 degenerated patterns, and that
the experimental data is well reproduced if the 2 patterns appears
simultaneously. We believe that the low temperature structure contains stacking
faults separating regions corresponding to the four possible patterns.Comment: Submitted to Phys. Rev. Lett., 4 pages, 4 eps figures inserted in the
tex
Zone-selection effect of photoelectron intensity distributions in a nonsymmorphic system RAlSi (R : Ce and Nd)
We investigate the electronic structures of noncentrosymmetric Weyl
semimetals RAlSi (R: Ce and Nd) using soft x-ray angle-resolved photoemission
spectroscopy. We find that the photoelectron intensity distribution observed in
the momentum-resolved electronic bands is highly sensitive to the covered
Brillouin zone (BZ) due to the zone-selection effect arising from the
nonsymmorphic crystal structure of RAlSi. Our data reconstruct the
photoelectron distributions varied according to the zone-selection effect, and
reveal comprehensive information about the electronic band structures
reproduced by band calculations. This detailed information enables us to
experimentally trace the Weyl-cone dispersion throughout three-dimensional
momentum space, providing valuable insights into the unique properties of
RAlSi
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