286 research outputs found
Emergent One-Dimensional Helical Channel in Higher-Order Topological Insulators with Step Edges
We study theoretically the electronic structure of three-dimensional (3D)
higher-order topological insulators in the presence of step edges. We
numerically find that a 1D conducting state with a helical spin structure,
which also has a linear dispersion near the zero energy, emerges at a step edge
and on the opposite surface of the step edge. Such a 1D helical conducting
state can exist when the Fermi level is in the bulk bandgap, as well as the
ordinary 1D topological hinge states. We also find that the 1D helical
conducting state on the opposite surface of a step edge emerges when the
electron hopping strength in the direction perpendicular to the step is weak.
In other words, the existence of the emergent 1D helical conducting state on
the opposite surface of a step edge can be understood by considering an
addition of different-sized independent blocks of 3D higher-order topological
insulators. Our finding paves the way for on-demand creation of 1D helical
conducting states from 3D higher-order topological insulators employing
experimental processes commonly used in thin-film devices, which could lead to,
e.g., a realization of high-density Majorana qubits.Comment: 11 pages, 10 figure
Reducing nonideal to ideal coupling in random matrix description of chaotic scattering: Application to the time-delay problem
We write explicitly a transformation of the scattering phases reducing the
problem of quantum chaotic scattering for systems with M statistically
equivalent channels at nonideal coupling to that for ideal coupling. Unfolding
the phases by their local density leads to universality of their local
fluctuations for large M. A relation between the partial time delays and
diagonal matrix elements of the Wigner-Smith matrix is revealed for ideal
coupling. This helped us in deriving the joint probability distribution of
partial time delays and the distribution of the Wigner time delay.Comment: 4 pages, revtex, no figures; published versio
AC resistivity of d-wave ceramic superconductors
We model d-wave ceramic superconductors with a three-dimensional lattice of
randomly distributed Josephson junctions with finite self-inductance. The
linear and nonlinear ac resistivity of the d-wave ceramic superconductors is
obtained as function of temperature by solving the corresponding Langevin
dynamical equations. We find that the linear ac resistivity remains finite at
the temperature where the third harmonics of resistivity has a peak. The
current amplitude dependence of the nonlinear resistivity at the peak position
is found to be a power law. These results agree qualitatively with experiments.
We also show that the peak of the nonlinear resistivity is related to the onset
of the paramagnetic Meissner effect which occurs at the crossover temperature
, which is above the chiral glass transition temperature .Comment: 7 eps figures, Phys. Rev. B (in press
Alterations of circulating endothelial cell and endothelial progenitor cell counts around the ovulation.
Context:Circulating endothelial cells (CECs) and progenitor cells (CEPs) have been intensively studied as a promising tool for treating ischemic diseases and monitoring cancer treatments, but how the menstrual cycle affects the variation in their counts remains unclear. Objective:The aims of the study were to determine the influence of the menstrual cycle on the number of CECs and CEPs and to investigate the association of their counts with circulating hormones and angiogenesis-associated factors. Design:CEP and CEC counts by flow cytometry and the CellSearch system and circulating factor levels were measured eight times during the menstrual cycle in 18 volunteers. The menstrual cycle was divided into six phases based on hormone concentrations. Results:CEP counts peaked in the periovulatory and middle luteal phases with a drop in the early luteal phase. CEC counts showed no significant variation. There were significant correlations between the CEP counts and the serum concentrations of estradiol (E2), LH, and granulocyte colony-stimulating factor (G-CSF) (P < 0.0001, P < 0.0001, and P = 0.01, respectively). The difference in CEP counts between two adjacent phases was significantly correlated with that in E2, LH, G-CSF, and serum vascular endothelial growth factor (P < 0.0001, P < 0.0001, P = 0.02, and P = 0.006, respectively). Conclusion:CEP counts peaked in the periovulatory and middle luteal phases, with a drop in the early luteal phase, and were correlated with serum E2, LH, and G-CSF concentrations. Consideration of the variation in CEP counts would be important for the clinical application of CEPs
ジドウ ソウサホウ ニヨル ガン チリョウヨウ 125 I シード ホウシャセン キョウド ケンテイ システム ノ カイハツ
A new scanning system using a NaI(Tl) scintillation survey meter, copper slit and drive-unit has been
developed for quality control of radioactive seeds. Radioactive seed implants, also called brachytherapy, are
widely used modality in the treatment of early stage prostate cancers. Seeds containing the iodine-125 are most
commonly used for permanent implant prostate brachytherapy. These seeds are commercially available and
delivered in a sterile environment in the form of packaged cartridge. It is impractical to re-sterilize and re-load
seeds after calibration. This paper describes a new method to calibrate all seeds in the seed cartridge in a sterile
package
Which Side-Bending X-ray Position is Better to Evaluate the Preoperative Curve Flexibility in Adolescent Idiopathic Scoliosis Patients, Supine or Prone?
Study Design Prospective cohort study. Purpose The present study aimed to evaluate the difference in the preoperative curve flexibility between the supine and prone positions in patients with adolescent idiopathic scoliosis (AIS). Overview of Literature In AIS, a side-bending view is necessary to differentiate a structural curve from a nonstructural curve using the Lenke classification system. However, there are no published studies about which position, supine or prone, is more effective when evaluating preoperative curve flexibility using side-bending X-ray images in AIS patients. Methods Radiographs were analyzed for 32 AIS patients (26 females, six males) who underwent posterior correction and fusion of their main thoracic (MT) curves. Cobb angles of MT, proximal thoracic (PT), and thoracolumbar/lumbar (TL/L) curves were measured preoperatively using upright, supine (anteroposterior and side-bending), and prone (posteroanterior and side-bending) X-rays. Results The average Cobb angles of PT, MT, and TL/L curves on preoperative upright/supine/prone X-rays were 29.1°/26.7°/26.6°, 60.7°/48.5°/48.2°, and 41.0°/32.6°/33.1°, respectively. The average Cobb angles of PT, MT, and TL/L curves on supine/prone sidebending X-rays were 19.2°/20.3°, 36.3°/36.4°, and 13.9°/15.7°, respectively. The flexibility rates of PT, MT, and TL/L curves in supine/prone positions were 35.3%/32.5%, 40.6%/40.2%, and 71.7%/68.2%, respectively. Comparing flexibility rates in the prone position with those in the supine position in each case, the average ratios of PT, MT, and TL/L curves were found to be 1.0, 1.0, and 0.9, respectively. There were no statistically significant differences between supine and prone side-bending X-ray measurements. However, the Lenke classification in six of 32 patients (18.8%) differed between supine and prone positions because the TL/L curve in the supine position was slightly more flexible than in the prone position. Conclusions Supine side-bending films may be suitable for the evaluation of preoperative curve flexibility in AIS, especially for lumbar modifier C
Association of Clinical Features with Human Leukocyte Antigen in Japanese Patients with Ulcerative Colitis
【Background】 The human leukocyte antigen (HLA) region has been found to be involved in the pathogenesis of inflammatory bowel disease (IBD), which is classified into ulcerative colitis (UC) and Crohn’s disease (CD), by genome-wide association studies. The aim of this study was to confirm whether HLA-alleles confer susceptibility to UC and to determine whether HLA-allel1es are associated with the clinical phenotypes in Japanese patients with UC. 【Methods】 In this study, HLA typing was performed by PCR-sequence-specific oligonucleotides (PCR-SSO) to confirm the correlation between UC and HLA alleles (for HLA-A, B, DRB1) in 45 Japanese UC patients. In addition, whether the HLA alleles are related to patient and clinical background characteristics was examined. 【Results】 Overall, 62.2%, and 66.7% of the 45 UC patients had HLA-B*52 and HLA-DRB1*15, respectively. These allele frequencies were significantly higher than in previously reported Japanese control persons (P < 0.0001). The frequencies of extraintestinal manifestations [odds ratio (OR) = 0.12, P = 0.039] and a history of colectomy (OR = 0.18, P = 0.046) were lower in HLA-B*52-positive UC patients than in HLA-B*52 negative UC patients. The white blood cell (WBC) count was significantly higher in HLA-DRB1*15-positive patients (9430 ± 4592/μL) than in HLA-DRB1*15-negative patients (6729 ± 2160/μL). Thus, HLA-B*52 and DRB1*15 appear to be associated with disease features and severity in Japanese UC patients. 【Conclusion】 These results indicate that HLA-B*52 and DRB1*15 are not only associated with overall UC susceptibility, but also with the clinical phenotypes in Japanese patients
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