Serum free fatty acids levels not associated with normal tension glaucoma

Kenya Yuki, Itaru Kimura, Kazuo TsubotaDepartment of Ophthalmology, Keio University School of Medicine, Tokyo, JapanPurpose: To determine the free fatty acid levels in the sera of patients with normal-tension glaucoma and compare it with that of normal controls.Methods: Forty-four consecutive patients with newly diagnosed normal-tension glaucoma and forty-four age and gender matched controls were evaluated. The type and level of fatty acids in the sera were measured by gas chromatography (Model GC17A; Shimazu, Kyoto, Japan). Twenty-four fatty acids were identified from 12:0 to 24:1. The values were compared between the normal-tension glaucoma and control groups by Mann–Whitney U tests.Results: No statistically significant difference was found in the levels of any free fatty acids between the normal-tension glaucoma group and control group.Conclusion: No significant association was found in the serum free fatty acids levels including docosahexaenoic acid and eicosapentaenoic acid between normal-tension glaucoma patients and controls.Keywords: free fatty acid, docosahexaenoic acid, eicosapentaenoic acid, normal tension glaucom

Observation of a Highly Spin Polarized Topological Surface State in GeBi2_{2}Te4_{4}

Spin polarization of a topological surface state for GeBi$_2$Te$_4$, the newly discovered three-dimensional topological insulator, has been studied by means of the state of the art spin- and angle-resolved photoemission spectroscopy. It has been revealed that the disorder in the crystal has a minor effect on the surface state spin polarization and it exceeds 75% near the Dirac point in the bulk energy gap region ($\sim$180 meV). This new finding for GeBi$_{2}$Te$_{4}$ promises not only to realize a highly spin polarized surface isolated transport but to add new functionality to its thermoelectric and thermomagnetic properties.Comment: 5 pages, 4 figure

Dichotomy Between Orbital and Magnetic Nematic Instabilities in BaFe2S3

Nematic orders emerge nearly universally in iron-based superconductors, but elucidating their origins is challenging because of intimate couplings between orbital and magnetic fluctuations. The iron-based ladder material BaFe2S3, which superconducts under pressure, exhibits antiferromagnetic order below TN ~ 117K and a weak resistivity anomaly at T* ~ 180K, whose nature remains elusive. Here we report angle-resolved magnetoresistance (MR) and elastoresistance (ER) measurements in BaFe2S3, which reveal distinct changes at T*. We find that MR anisotropy and ER nematic response are both suppressed near T*, implying that an orbital order promoting isotropic electronic states is stabilized at T*. Such an isotropic state below T* competes with the antiferromagnetic order, which is evidenced by the nonmonotonic temperature dependence of nematic fluctuations. In contrast to the cooperative nematic orders in spin and orbital channels in iron pnictides, the present competing orders can provide a new platform to identify the separate roles of orbital and magnetic fluctuations.Comment: 7 pages 5 figures, to be published in Phys. Rev. Re

Observation of warping effects in the band and angular momentum structures of topological insulator Bi2Te3

We performed angle resolved photoemission (ARPES) experiments on Bi2Te3 with circularly polarized light. ARPES data show very strong circular dichroism, indicating existence of orbital angular momentum (OAM). Moreover, the alignment of OAM is found to have a strong binding energy dependence. Such energy dependence comes from a relatively strong band warping effect in Bi2Te3 compared to Bi2Se3. OAM close to Dirac point has an ideal chiral structure (sin ?) without out-of-plane component. Warping effect comes in as the binding energy decreases and circular dichroism along a constant energy contour can no longer be explained by a simple sin? function but requires a sin3? term. When the warping effect becomes even stronger near the Fermi energy, circular dichroism gains an additional sin6? term. Such behavior is found to be compatible with the theoretically predicted OAM structure

Massless or heavy due to two-fold symmetry : Surface-state electrons at W(110)

The C2v symmetry of the W(110) surface influences strongly the spin-polarized Dirac-cone-like surface state within a spin-orbit-induced symmetry gap. We present a detailed angle-resolved photoemission study with s- and p-polarized light along three different symmetry lines. The Dirac-cone-like feature appears along ΓH̅ and ΓS̅ while it is strongly deformed along ΓN̅ . A two-fold Σ3 symmetry of the d-type surface state is identified from photoemission experiments using linearly polarized light. Our results are well described by model calculations based on an effective Hamiltonian with C2v symmetry. The flattened Dirac cone of the surface state is caused by hybridization with bulk continuum states of Σ1 and Σ2 symmetry. The spin texture of this state obtained from the model calculations shows a quasi-one-dimensional behavior. This finding opens a new avenue in the study of d-electron-based persistent spin helix systems and/or weak topological insulators

Different Patterns of Vascular Response Between Patients With or Without Diabetes Mellitus After Drug-Eluting Stent Implantation Optical Coherence Tomographic Analysis

ObjectivesWe performed this study to investigate with optical coherence tomography (OCT) the vascular response after sirolimus-eluting stent (SES) implantation between patients with and those without diabetes mellitus (DM).BackgroundThe difference in vascular response after SES implantation between patients with and those without DM has not been fully evaluated with OCT.MethodsOptical coherence tomography was performed to examine 74 nonrestenotic SES implanted in 63 patients (32 with DM and 31 without DM) at 9 months after SES implantation. For struts showing neointimal coverage, the neointimal thickness on the luminal side of each strut section was measured, and neointimal characteristics were classified into high, low, and layered signal pattern.ResultsBaseline patient characteristics and lesion and procedural characteristics data were similar between the 2 groups. In total, 11,422 struts were analyzed. High signal neointima was observed in 90.2 ± 13.9%, low signal neointima in 7.3 ± 10.0%, and layered neointima in 2.7 ± 5.8%/stents. There was higher incidence of low signal neointima (10.5 ± 10.3% vs. 4.5 ± 5.6%, p = 0.003), neointimal thickness was larger (median: 106.8 μm, interquartile range: 79.3 to 130.4 μm vs. median: 83.5 μm, interquartile range: 62.3 to 89.3 μm; p < 0.0001), and neointimal coverage of stent struts was higher (92.1 ± 6.2% vs. 87.2 ± 11.9%; p = 0.03) in DM patients.ConclusionsHigh signal neointimal pattern was predominantly observed, and low or layered signal pattern was observed in some cases. In DM patients, low signal neointima was observed with high frequency. Neointimal coverage and neointimal thickness was also higher in DM patients as compared with non-DM patients

Persistence of the topological surface states in Bi2Se3 against Ag intercalation at room temperature

The electronic and atomic structures of topological insulator Bi2Se3, upon Ag atom deposition, have been investigated by combined experimental methods of scanning tunneling microscopy (STM), photoelectron spectroscopy, and first-principles calculations. We show from the results of STM that the deposited Ag atoms are stabilized beneath the surface instead of being adsorbed on the topmost surface. We further reveal from the angle-resolved photoemission spectroscopy that the Bi2Se3(0001) topological surface states stay uninterrupted after a large amount of absorption of Ag atoms. Our analysis of the photoelectron intensity of Ag core states excited by soft X-ray suggests that a large amount of deposited Ag atoms diffused into a deeper place, which is beyond the probing depth of X-ray photoelectron spectroscopy. The first-principles calculations identify the octahedral site in the van der Waals gaps between quintuple layers to be the most favorable locations of Ag atoms beneath the surface, which yields good agreement between the simulated and experimental STM images. These findings pave an efficient way to tailor the local lattice structures of topological insulators without disturbing the topologically nontrivial surface states