Impurity effect on Bogoliubov Fermi surfaces: Analysis based on iron-based superconductors

The effect of impurities on a superconductor with Bogoliubov Fermi surfaces (BFSs) is studied using a realistic tight-binding model. Based on the band structure composed of $d$-orbitals in tetragonal FeSe, whose S-doped sample is a potential material for BFS, we construct the superconducting state by introducing a time-reversal broken pair potential in terms of the band index. We further consider the effect of impurities on the BFS, where the impurity potential is defined as a local potential for the original $d$-orbitals. The self-energy is calculated using the (self-consistent) Born approximation, which shows an enhancement of the single-particle spectral weight on the Fermi surface. This is consistent with the previous phenomenological theory and is justified by the present more detailed calculation based on the FeSe-based material.Comment: 14 pages, 6 figure

Optical switching of nematic liquid crystal by means of photoresponsive polyimides as an alignment layer

Photosensitive polyimides (PIs) as an alignment layer induced optical switching of nematic liquid crystal (NLC) on photoirradiation at 366 nm. The orientation of NLC molecule was changed from homogeneous to homeotropic alignment on photoirradiation with a dc electric field as a bias. The optical switching behavior of NLC was largely affected by the chemical structures of PIs. (C) 1999 American Institute of Physics. [S0003-6951(99)02748-5]open91

メタヒューリスティクスおよび機械学習を用いた建物・地域エネルギーシステムの最適化に関する研究

学位の種別: 課程博士審査委員会委員 : （主査）東京大学教授 大岡 龍三, 東京大学教授 加藤 信介, 東京大学教授 赤司 泰義, 東京大学教授 合原 一幸, 東京大学講師 菊本 英紀University of Tokyo(東京大学

Necessity for Reassessment of Patients with Serogroup 2 Hepatitis C Virus (HCV) and Undetectable Serum HCV RNA

We encountered a patient positive for anti-hepatitis C virus (HCV) whose serum HCV RNA was undetectable with the Roche AmpliPrep/Cobas TaqMan HCV assay (CAP/CTM) version 1 but showed a high viral load with the Abbott RealTime HCV assay (ART). Discrepancies in the detectability of serum HCV RNA were investigated among 891 consecutive patients who were positive for anti-HCV. Specific nucleotide variations causing the undetectability of HCV RNA were determined and confirmed by synthesizing RNA coding those variations. Serum samples with the discrepancies were also reassessed by CAP/CTM version 2. Among the 891 anti-HCV-positive patients, 4 patients had serum HCV RNA levels that were undetectable by CAP/CTM version 1 despite having levels of > 5 log IU/ml that were detected by ART. All four patients had HCV genotype 2a and high titers of anti-HCV. Sequencing of the HCV 5' noncoding regions revealed 2 common variations, A at nucleotide (nt) 145 and T at nt 151. Synthesized RNAs of the HCV 5' noncoding region with standard (NCR145G151C) and variant nucleotides at nt 145 and nt 151 were quantified with CAP/CTM. RNAs of NCR145G151C and NCR145G151T were quantifiable with CAP/CTM version 1, while those of NCR145A151T and NCR145A151C went undetected. The substitution from G to A at nt 145 specifically conferred this undetectability, while this undetectability was reverted in synthesized HCV RNA with correction of this variation. Reassessment of these samples by CAP/CTM version 2 resulted in similar levels of HCV RNA being detected by ART. We conclude that HCV patients with undetectable HCV RNA by CAP/CTM version 1 should be reassessed for viral quantification

Low-power display system enabled by combining oxide semiconductor and neural network technologies

An oxide semiconductor (OS)-based field effect transistor (OSFET) exhibits the advantage of having an extremely low off-state current; moreover, the OSFET displays an off-state current that is ten orders of magnitude lower than that of a CMOS-FET [1]. Recently, numerous applications that harness this feature have been reported [2]. For instance, charge leakage from a data retention node of a pixel significantly decreases when the display incorporates OSFETs in its pixel circuit (OS display) [3, 4]. This minimizes degradation in the image quality when the displayed image is static despite using lower refresh rates. Consequently, the consumed power of the display driver circuit can be reduced by a large margin. This driving method is termed idling stop (IDS) driving. The OSFET’s low-leakage can also effectively enable a type of ULSICs that we term OS-large-scale integrated circuits (OSLSI) [5, 6]. Please click Additional Files below to see the full abstract

Astrocytic Tau Pathologies in Argyrophilic Grain Disease and Related Four-repeat Tauopathies

Neurodegenerative diseases in which tau accumulation plays a cardinal role in the pathogenic process are called tauopathies, and when tau isoforms having four repeats of the microtubule binding sites, four-repeat tau, are selectively accumulated as pathological hallmarks, the term four-repeat tauopathy is used. The major four-repeat tauopathies are progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), and argyrophilic grain disease (AGD). Historically, neuronal cytopathologies, e.g., neurofibrillary tangles and ballooned neurons, were emphasized as characteristic lesions in PSP and CBD. Now, however, astrocytic tau pathologies, i.e., tufted astrocytes (TAs) and astrocytic plaques (APs), are considered to be highly disease-specific lesions. Although granular/fuzzy astrocytes (GFAs) frequently develop in the limbic system in AGD cases, the specificity is not conclusive yet. Some AGD cases have a few TAs, and to a lesser frequency, a few APs in the frontal cortex and subcortical nuclei. The number of astrocytic tau pathologies including TAs and GFAs increases with the progression of AGD. In this paper, histopathological features of astrocytic tau pathologies in PSP, CBD, and AGD are first reviewed. Then, recent findings regarding the coexistence of these tauopathies are summarized from a viewpoint of astrocytic tau pathologies. Further biochemical and pathological studies focusing tau-positive astrocytic lesions may be useful to increase understanding of the pathological process in four-repeat tauopathies and to develop novel therapeutic strategies for patients with these diseases

Aberrant Expression of Keratin 7 in Hepatocytes as a Predictive Marker of Rapid Progression to Hepatic Failure in Asymptomatic Primary Biliary Cirrhosis

A predictive marker of the rapid progression to hepatic failure is desired for patients with asymptomatic primary biliary cirrhosis (aPBC). We performed a systematic cohort analysis of 101 patients diagnosed as having aPBC and the rapid progression to liver failure in some, by focusing on cholestasis. Cholestasis was assessed by aberrant keratin7 (K-7) expressions in the patientsʼ hepatocytes. Intralobular expressions of K-7 were found in 9 of the 101 patients. The grades of K-7 expression were significantly associated with the levels of alanine aminotransferase, alkaline phosphatase, and total bilirubin at the time of diagnosis, but not with bile duct loss or cholestasis. Stepwise logistic regression analysis revealed that high grades of K-7 expression correlated positively with high levels of total bilirubin. During the follow-up period, 8 patients developed jaundice, and the mean period until the development of jaundice was 5.2 years. The proportional hazards models for the risk of developing jaundice identified a high grade of aberrant K-7 expression in hepatocytes as the only significant risk factor. Aberrant K-7 expression in hepatocytes can be used as an additional marker to predict rapid progression to liver failure in patients with aPBC at the time of diagnosis