375 research outputs found
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
Neutron Diffraction Study of Field Cooling Effects on Relaxor Ferroelectrics Pb[(Zn_{1/3} Nb_{2/3})_{0.92} Ti_{0.08}] O_{3}
High-temperature (T) and high-electric-field (E) effects on Pb[(Zn_{1/3}
Nb_{2/3})_{0.92} Ti_{0.08}]O_3 (PZN-8%PT) were studied comprehensively by
neutron diffraction in the ranges 300 <= T <= 550 K and 0 <= E <= 15 kV/cm. We
have focused on how phase transitions depend on preceding thermal and
electrical sequences. In the field cooling process (FC, E parallel [001] >= 0.5
kV/cm), a successive cubic (C) --> tetragonal (T) --> monoclinic (M_C)
transition was observed. In the zero field cooling process (ZFC), however, we
have found that the system does not transform to the rhombohedral (R) phase as
widely believed, but to a new, unidentified phase, which we call X. X gives a
Bragg peak profile similar to that expected for R, but the c-axis is always
slightly shorter than the a-axis. As for field effects on the X phase, we found
an irreversible X --> M_C transition via another monoclinic phase (M_A) as
expected from a previous report [Noheda et al. Phys. Rev. Lett. 86, 3891
(2001)]. At a higher electric field, we confirmed a c-axis jump associated with
the field-induced M_C --> T transition, which was observed by strain and x-ray
diffraction measurements.Comment: 8 pages, 9 figures, revise
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
P-12. An established murine intestinal epitheliocyte (MIE) cell line(Abstracts of the International Symposium on Recent Advances in Animal Science(IS-RAAS),Joint meeting of 2^<nd> IS-AS and 3^<rd> IS-IFS)
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 – 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
Symmetry of high-piezoelectric Pb-based complex perovskites at the morphotropic phase boundary I. Neutron diffraction study on Pb(Zn1/3Nb2/3)O3 -9%PbTiO3
The symmetry was examined using neutron diffraction method on
Pb(Zn1/3Nb2/3)O3 -9%PbTiO3 (PZN/9PT) which has a composition at the
morphotropic phase boundary (MPB) between Pb(Zn1/3Nb2/3)O3 and PbTiO3. The
results were compared with those of other specimens with same composition but
with different prehistory. The equilibrium state of all examined specimens is
not the mixture of rhombohedral and tetragonal phases of the end members but
exists in a new polarization rotation line Mc# (orthorhombic-monoclinic line).
Among examined specimens, one exhibited tetragonal symmetry at room temperature
but recovered monoclinic phase after a cooling and heating cycle
Low-Temperature Structure of the Quarter-Filled Ladder Compound alpha'-NaV2O5
The low-temperature (LT) superstructure of -NaVO was
determined by synchrotron radiation x-ray diffraction. Below the phase
transition temperature associated with atomic displacement and charge ordering
at 34K, we observed the Bragg peak splittings, which evidence that the LT
structure is monoclinic. It was determined that the LT structure is
with the space group where and
represent the high temperature orthorhombic unit cell. The valence estimation
of V ions according to the bond valence sum method shows that the V sites are
clearly separated into two groups of V and V with a
charge ordering pattern. This LT structure is consistent with resonant x-ray
and NMR measurements, and strikingly contrasts to the LT structure previously
reported, which includes V sites.Comment: 4 pages, 3 figures, 1 tabl
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