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1.
Osteoporos Int ; 33(6): 1275-1284, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35091788

ABSTRACT

The baseline sagittal vertical axis (SVA) and pelvic tilt (PT) are independent risk factors of osteoporosis-related fractures in women with osteoporosis. We clarified the SVA and PT to predict the incidence of osteoporosis-related fractures. PURPOSE: Sagittal alignment with osteoporosis women deteriorates with advancing age and sagittal alignment may indicate osteoporosis-related fractures in the future. However, whether the sagittal alignment predicts future osteoporosis-related fracture in patients with osteoporosis has not been clarified. We aimed to investigate the association between sagittal alignment and future osteoporosis-related fractures. METHODS: This was a retrospective cohort study. Of the 313 participants (mean follow-up period, 2.9 years), 236 were included in the analysis. At baseline, we measured bone mineral density (BMD) of the lumbar spine and the femoral neck, sagittal vertical axis (SVA), thoracic kyphosis, pelvic incidence minus lumbar lordosis, sacral slope, pelvic tilt (PT), geriatric locomotive function scale (GLFS), two-step value, and stand-up test. The information on medications and the duration of treatment were reviewed from the medical records. Additionally, participants reported their history of falls at baseline. Multiple logistic regression analysis was used to determine the association of future osteoporosis-related fracture, and adjusted Odds ratios (OR) and 95% confidence interval (CI) were calculated with all predictors as covariates. All continuous variables were calculated using standardized OR (sOR). RESULTS: Osteoporosis-related fractures occurred in 33 of 313 participants (10.5%). Multiple logistic regression analysis showed that a history of falls (OR =4.092, 95% CI: 1.029-16.265, p =0.045), SVA (sOR =4.228, 95% CI: 2.118-8.439, p <0.001), and PT (sOR =2.497, 95% CI: 1.087-5.733, p =0.031) were independent risk factors for future osteoporosis-related fractures. CONCLUSIONS: This study revealed the SVA and PT to predict osteoporosis-related fractures. TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION: UMIN000036516 (April 1, 2019).


Subject(s)
Kyphosis , Lordosis , Osteoporosis , Osteoporotic Fractures , Aged , Female , Humans , Kyphosis/etiology , Lumbar Vertebrae/diagnostic imaging , Osteoporosis/complications , Osteoporosis/epidemiology , Osteoporotic Fractures/complications , Osteoporotic Fractures/etiology , Outpatients , Retrospective Studies
2.
J Phys Chem B ; 119(24): 7186-97, 2015 Jun 18.
Article in English | MEDLINE | ID: mdl-25495843

ABSTRACT

We present a computational study of the dynamical and electronic structure origins of the impact of anchoring groups, PO3H2, COOH, and OH, on the efficiency of photochemical CO2 reduction in Ru(di-X-bpy)(CO)2Cl2/Ta2O5 systems. Recent experimental studies indicate that the efficiency may not directly correlate with the driving force for electron transfer (ET) in these systems, prompting the need for further investigation of the role of anchor groups. Our analysis shows that there are at least two key roles of the anchor in determining the efficiency of CO2 reduction by the Ru complex. First, depending on local steric interactions, different tilting angles and their fluctuations may emerge for different anchors, affecting the magnitude of the donor-acceptor coupling. Second, depending on localization of acceptor states on the anchor, determined by the anchor's tendency to form conjugate subsystems, the yields of ET to the catalytic center may vary, directly affecting the photocatalytic efficiency. Finally, our calculations indicate that surface modeling with N-doping and many-body effects are needed to describe the ET process in the systems properly. N-doping imparts the Ta2O5 surface with a dipole moment, while Coulomb and exchange contributions to the electron-hole interaction can produce excitons that should be taken into account.

3.
Chem Commun (Camb) ; 50(33): 4315-8, 2014 Apr 28.
Article in English | MEDLINE | ID: mdl-24637925

ABSTRACT

We have developed a novel synthetic route for the production of fine Mg2Si particles (<1 µm) using NaSi, MgCl2, and Na. Mg2Si was suggested to be formed by a solid-state metathesis reaction, in which MgCl2 reacts with Na to form Mg and NaCl, and then Mg reacts with NaSi.

4.
J Phys Condens Matter ; 23(40): 404203, 2011 Oct 12.
Article in English | MEDLINE | ID: mdl-21931185

ABSTRACT

First-principles calculations of the band offsets between Cu(2)ZnSnS(4) (CZTS) and XS (X = Cd, Zn) are performed. While the interface dipole contribution for the band offsets is calculated using the Perdew-Burke-Ernzerhof functional, the Heyd-Scuseria-Ernzerhof hybrid functional is employed to introduce the quasiparticle corrections to the band offsets. The calculated conduction band offset between CZTS and CdS is 0.2 eV, validating CdS for the buffer layer of the CZTS solar cell. The small conduction band offset stems from the band gap narrowing of CdS under the interface strain caused by the lattice misfit with CZTS. A large valence band offset over 0.9 eV between CZTS and ZnS indicates that precipitated ZnS is regarded as an inactive insulator phase in CZTS absorbers.

5.
J Phys Condens Matter ; 20(27): 275228, 2008 Jul 09.
Article in English | MEDLINE | ID: mdl-21694389

ABSTRACT

The first-principles FLAPW (full potential linearized augmented plane wave) electronic structure calculations were performed for the Ag(5)Li(8) gamma-brass, which contains 52 atoms in a unit cell and has been known for many years as one of the most structurally complex alloy phases. The calculations were also made for its neighboring phase AgLi B2 compound. The main objective in the present work is to examine if the Ag(5)Li(8) gamma-brass is stabilized at the particular electrons per atom ratio e/a = 21/13 in the same way as some other gamma-brasses like Cu(5)Zn(8) and Cu(9)Al(4), obeying the Hume-Rothery electron concentration rule. For this purpose, the e/a value for the Ag(5)Li(8) gamma-brass as well as the AgLi B2 compound was first determined by means of the FLAPW-Fourier method we have developed. It proved that both the gamma-brass and the B2 compound possess an e/a value equal to unity instead of 21/13. Moreover, we could demonstrate why the Hume-Rothery stabilization mechanism fails for the Ag(5)Li(8) gamma-brass and proposed a new stability mechanism, in which the unique gamma-brass structure can effectively lower the band-structure energy by forming heavily populated bonding states near the bottom of the Ag-4d band.

6.
Phys Rev Lett ; 89(19): 197601, 2002 Nov 04.
Article in English | MEDLINE | ID: mdl-12443147

ABSTRACT

The technologically important prediction of Auger recombination lifetimes in semiconductors is addressed by means of a fully first-principles formalism, based on precise energy bands and wave functions provided by the full-potential linearized augmented plane wave code. The minority carrier Auger lifetime is determined by two related approaches: (i) a direct evaluation within Fermi's golden rule, and (ii) an indirect evaluation, based on a detailed balance formulation combining Auger recombination and its inverse process, impact ionization, in a unified framework. Lifetimes determined with the direct and indirect methods show excellent consistency between them (i) for n-doped GaAs and (ii) with measured values for GaAs and InGaAs. This indicates the computational formalism as a new sensitive tool for use in materials performance optimization.

7.
Science ; 293(5528): 269-71, 2001 Jul 13.
Article in English | MEDLINE | ID: mdl-11452117

ABSTRACT

To use solar irradiation or interior lighting efficiently, we sought a photocatalyst with high reactivity under visible light. Films and powders of TiO(2-x)N(x) have revealed an improvement over titanium dioxide (TiO2) under visible light (wavelength < 500 nanometers) in optical absorption and photocatalytic activity such as photodegradations of methylene blue and gaseous acetaldehyde and hydrophilicity of the film surface. Nitrogen doped into substitutional sites of TiO2 has proven to be indispensable for band-gap narrowing and photocatalytic activity, as assessed by first-principles calculations and x-ray photoemission spectroscopy.

8.
Proc Natl Acad Sci U S A ; 98(13): 7113-6, 2001 Jun 19.
Article in English | MEDLINE | ID: mdl-11416196

ABSTRACT

Materials with high electrical conductivity and optical transparency are needed for future flat panel display, solar energy, and other opto-electronic technologies. In(x)Cd(1-x)O films having a simple cubic microstructure have been grown on amorphous glass substrates by a straightforward chemical vapor deposition process. The x = 0.05 film conductivity of 17,000 S/cm, carrier mobility of 70 cm2/Vs, and visible region optical transparency window considerably exceed the corresponding parameters for commercial indium-tin oxide. Ab initio electronic structure calculations reveal small conduction electron effective masses, a dramatic shift of the CdO band gap with doping, and a conduction band hybridization gap caused by extensive Cd 5s + In 5s mixing.

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