344 research outputs found
Development of Supreme Super High-Density Realtime Disaster Mitigation System for Gas Supply System
With the 3,700 New SI sensors installed throughout its service area (3,100 km2), Tokyo Gas has started to develop its super high-density real-time disaster mitigation system SUPREME for gas supply systems. Immediately after an earthquake, seismic data from the New SI sensors is relayed to the main system where extremely precise estimates of the damage are made on the spot. Damage estimation consists of making an estimate of the surface distribution of seismic motion that takes account of the site amplification factor, and making an estimate of damage to the pipeline network that takes account of factors such as the types of the pipes, the topography of the area, and the liquefaction conditions
Analysis of IGZO crystalline structure and its stability by first-principles calculations
In-Ga-Zn oxide (IGZO), an oxide semiconductor, has been actively researched as a semiconductor material having features different from those of silicon in recent years [1]. IGZO is used as a transistor material in backplanes of commercially available displays. Transistors including crystalline IGZO have high stability and thus are suitable for mass production [2].
Our previous studies revealed that the selected area diffraction pattern of an IGZO film formed at room temperature by sputtering is a halo pattern, whereas diffraction spots are observed in the diffraction pattern obtained by nanobeam electron diffraction with a probe diameter of 1 nm [3,4]. These results suggest that the IGZO film has rather nanometer-sized crystalline structures than a completely amorphous structure. We named this film “nano-crystalline IGZO (nc-IGZO) film.” Other researchers have reported that the nc-IGZO film has a crystalline-cluster composite structure, according to the analysis results obtained by grazing-incidence X-ray diffraction, anomalous X-ray scattering, and reverse-Monte-Carlo simulation [5].
In this study, an IGZO structure having a minute crystalline region, which was considered to exist in nc-IGZO as a local structure, was created by first-principles calculations and its stability was analyzed. The IGZO model having a crystalline region used in this study was obtained by a melt-quench method in the following manner. Note that the initial structure had a hexagonal-prism crystalline region at the center and an amorphous region (random atomic arrangement) around the crystalline region. The composition ratio was In:Ga:Zn:O = 1:1:1:4 and the density was 6.1 g/cm3. First, for structural relaxation with the crystalline region maintained, the amorphous region was fused in quantum molecular dynamics simulation (3500 K, 6 ps) while the atomic arrangement of the crystalline region was fixed, and the structure was cooled to 500 K at a rate of 500 K/ps and held at 300 K for 5 ps. Finally, the entire structure including the crystalline region was optimized towards the target structure (Fig. 1). An amorphous model was also created for reference. The amorphous model was obtained by quantum molecular dynamics simulation of the entire structure under similar temperature conditions without fixing the atomic arrangement of the crystalline region, followed by structural optimization. The comparison between the two models showed that the total energy of the IGZO model having a crystalline region was lower than that of the amorphous model (not having a crystalline region). This suggests that the crystalline region contributes to structure stabilization.
Please click Additional Files below to see the full abstract
Rashba-Dresselhaus spin-orbit coupling and polarization-coupled luminescence in an organic single crystal microcavity
Spin-orbit coupling (SOC) of light plays a fundamental photophysics that is
important for various fields such as materials science, optics, and quantum
technology, contributing to the elucidation of new physical phenomena and the
development of innovative applications. In this study, we investigate the
impact of SOC in a microcavity system using the highly oriented molecular
crystal. The unique molecular alignment of our crystal creates substantial
optical anisotropy, enabling the observation of significant SOC effects within
a microcavity form. Through angle-resolved photoluminescence measurements and
theoretical calculations, the presence of Rashba-Dresselhaus (RD) SOC in the
lower branch of polariton modes is revealed. We have observed for the first
time polarization-coupled emission from polariton modes due to the RD-SOC
effect in a microcavity with a medium having both strong light-matter coupling
and strong optical anisotropy. Theoretical investigations further elucidate the
intricate interplay between the RD-SOC effect and anisotropic light-matter
coupling, leading to the emergence of both circularly and diagonally polarized
mode splittings. This study not only advances our understanding of optical SOC
in microcavities but also highlights the potential of highly oriented molecular
crystals in manipulating SOC effects without external electric or magnetic
fields. These findings offer greatly promising platforms for developing
topological photonics and quantum technologies
A Case of Lobulated and Pedunculated Duodenal Hyperplastic Polyp Treated with Snare Polypectomy
We report herein the case of a lobulated and pedunculated hyperplastic polyp in the third portion of the duodenum causing anemia and occult blood in stools, which was detected by capsule endoscopy (CE) and treated with snare polypectomy. A 71-year-old man was referred to our hospital because of anemia and occult blood in stools. Three months earlier, he had been admitted to another hospital because of hemorrhage from gastric antral vascular ectasia (GAVE). Despite being treated for GAVE, hemoglobin decreased gradually. Esophagogastroduodenoscopy (EGD) and colonoscopy revealed no source of bleeding. However, CE revealed a polyp at the distal duodenum. Barium meal and EGD revealed a lobulated and pedunculated polyp in the third portion of the duodenum. The polyp was treated with snare polypectomy. Histopathological examination of the polyp revealed hyperplasia. After treatment of the polyp, the anemia improved gradually. To our knowledge, there are only 6 reported cases of a duodenal hyperplastic polyp, including our case. The polyp was pedunculated in only 2 cases and lobulated only in our case. Moreover, our case was diagnosed by CE. When a patient presents with anemia or obscure gastrointestinal bleeding undiagnosed by EGD and colonoscopy, CE is useful for detecting the bleeding lesion
Cutting error prediction by multilayer neural networks for machine tools with thermal expansion and compression
In training neural networks, it is important to reduce input variables for saving memory, reducing network size, and achieving fast training. This paper proposes two kinds of selecting methods for useful input variables. One of them is to use information of connection weights after training. If a sum of absolute value of the connection weights related to the input node is large, then this input variable is selected. In some case, only positive connection weights are taken into account. The other method is based on correlation coefficients among the input variables. If a time series of the input variable can be obtained by amplifying and shifting that of another input variable, then the former can be absorbed in the latter. These analysis methods are applied to predicting cutting error caused by thermal expansion and compression in machine tools. The input variables are reduced from 32 points to 16 points, while maintaining good prediction within 6 ホシm, which can be applicable to real machine tools
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
Late gadolinium enhancement on cardiac magnetic resonance predicts coronary vasomotor abnormality and myocardial lactate production in patients with chronic heart failure
Terpinen-4-ol inhibits colorectal cancer growth via reactive oxygen species
Terpinen-4-ol (TP4O) is the main component of the essential oil extracted from Melaleuca alternifolia, known as the tea tree, of the botanical family Myrtaceae. The anticancer effects of TP4O have been reported in several cancer cell lines. Previous reports have demonstrated that TP4O exerts anticancer effects by inducing apoptotic cell death in several cell lines; however, the underlying molecular mechanisms of these effects remain unclear. In the present study, the anticancer effects of TP4O against the colorectal cancer (CRC) cell lines HCT116 and RKO were evaluated using WST‑8 and bromodeoxyuridine assays. The mechanism of cell death was investigated by the measurement of caspase‑3/7, Annexin V and lactate dehydrogenase release. Reactive oxygen species (ROS) levels induced by TP4O were evaluated by electron spin resonance and quantitative measurement of dihydroethidium. Localization of the ROS derived from mitochondria was observed by confocal inverted microscopy. Protein levels of ROS scavengers were assessed by western blotting analysis. To confirm the role of ROS, cell viability was measured in the presence of antioxidant reagents. In an in vivo xenograft model of ICR‑SCID mice implanted with HCT116 cells, 200 mg/kg TP4O was injected locally, and tumor growth was compared with that of the control. TP4O induced apoptotic cell death in HCT116 and RKO cells in a dose‑dependent manner, and TP4O also increased the levels of ROS generated by mitochondria. TP4O‑induced cell death was rescued by administration of antioxidant regents. In vivo, TP4O inhibited the proliferation of HCT116 xenografts compared with that of the control group. The results of the present study suggest that TP4O induces apoptosis in CRC cells through ROS generation. Furthermore, TP4O is potentially useful for the development of novel therapies against CRC
- …