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Paper Scintillator Incorporated with Scintillator–Silica Fine Powders : Photophysical Characterization and Proof of Concept Demonstration of Tritium Detection
Get PDFIn order to decrease the generation of radioactive waste, it is of interest to develop a scintillator capable of absorbing tritiated solutions for efficient detection of low-energy β-particles from tritium. In this work, paper scintillator incorporated with scintillator–silica fine powders (FPs), which is composed of scintillator–silica nanoparticles (NPs) attached to silica FP, was fabricated and evaluated. The scintillator–silica NPs contained liquid scintillators benzoic acid, 2,5-diphenyloxazole (PPO), and 1,4-bis(5-phenyloxazol-2-yl) benzene (POPOP). Photophysical characterization was executed by means of photoluminescence, fluorescence lifetime, quantum efficiency, and radioluminescence under X-ray excitation. POPOP emission was confirmed by absorbing the emissions from benzoic acid and PPO. Radioluminescence results confirmed POPOP emission. Fluorescence lifetime analysis yielded a 1.29 ± 0.01 ns main fast decay (64.2%) combined with a 4.00 ± 0.04 ns slower decay (35.8%). The combined luminescence results suggested that most POPOP in the paper scintillator was solvated. At 301 nm, the average quantum efficiency from both faces of the paper scintillator was about 4%, and at 370 nm, it was about 11%. The paper scintillator detected 3H β-particles by dipping the paper scintillator into tritiated water without a liquid scintillator. The counting efficiency depended on water content in the paper scintillator, and it increased to above 10% for tritium activity less than 200 dpm since it was preferentially adsorbed by vapor pressure isotopic effect and isotopic exchanged tritium on the surface of the scintillator–silica FP in the paper scintillator.journal articl
社会福祉施設におけるBCP策定に向けた群衆シミュレーションの応用可能性に関する検討
Get PDF社会福祉施設における事業継続計画（BCP）の策定に際し，職員参集の基準を明確に定めることは，利用者および職員の安全を確保する上で重要である．しかし，従来のハザードマップを使用して，災害時の具体的なシナリオを時系列的に想像し，計画を策定することは困難である．本研究では，河川の氾濫による浸水を想定し，BCP策定のための群衆シミュレーションを実施した．本シミュレーションにより，各地域に居住する職員が，安全に施設へ移動できる時間帯や経路を把握することが可能となった．これにより，BCP策定，特に職員参集の最適なタイミングや方法をより具体的に計画するための新たなアプローチとしての可能性が示唆された．今後，社会福祉施設において，本研究成果を活用したBCP 策定に関するワークショップを実施し，その有用性を評価する．In the development of Business Continuity Plans (BCPs) for social welfare facilities, establishing clear criteria for emergency staff gathering is crucial in ensuring the safety of both users and staff members. However, it is difficult to utilize traditional hazard maps for imagining specific disaster scenarios on a timeseries basis and formulating corresponding plans. In this study, crowd simulations were conducted for BCP formulation, assuming flooding due to river overflow. These simulations enabled us to understand the times and routes that allow staff residing in each area to safely access the facility. This suggests the possibility of a new approach to BCP formulation, especially for more concrete planning of the optimal timing and methods for the emergency staff gathering. In the future, we will conduct workshops on BCP formulation at social welfare facilities using the results of this study and evaluate their usefulness.journal articl
Depth estimation of pipe wall thinning using multifrequency reflection coefficients of T(0,1) mode-guided waves with supervised multilayer perceptron
Get PDFThis study entailed the development of a novel method for estimating the depth of wall thinning of pipes using multifrequency (30–65 kHz) reflection coefficients (MRCs) of the T(0,1) mode guided waves and a multilayer perceptron (MLP). First, this study established why MRCs are a critical feature of the input layer of the MLP for the defect depth estimation of wall thinning. Further, a mathematical model that can quickly collect large amounts of training data was used to calculate the reflection waveforms. The depths of artificial and actual wall thinning were estimated using the MLP based on the MRCs and the mathematical model. Experiments were conducted using the T(0,1) mode guided waves to obtain the MRCs for 21 artificial and 6 actual wall thinnings to estimate the defect depths. A maximum of 8347 training data points were prepared using the mathematical model. Because the optimization of the MLP strongly depended on the initial weights and biases, 100 random initial values were prepared to evaluate the average estimations and their standard deviations. The classification scheme of the MLP was used, with classification step widths of 0.5 and 0.25 mm. The correct answer rates for the 21 artificial defects were 93% with a tolerance of ±0.5 mm for the 0.5 mm classification scheme; those for the 0.25 mm classification scheme were 89%. For the six actual defects, the correct answer rates were 100% with a tolerance of ±0.5 mm for both the 0.5- and 0.25 mm classification schemes. Sufficiently high correct answer rates were obtained in all the cases.journal articl
医用画像AI開発支援ソフトウェアを用いた歯科用CBCT画像における下顎管のセグメンテーション
Get PDFThe primary barrier to the development of artificial intelligence （AI） in medical imaging is data collection. Medical professionals generate training data for the development of medical imaging AI; however, this process is time-consuming and labor-intensive. Consequently, insufficient data collection frequently results in the premature discontinuation of AI model development. To address this challenge, we developed a software tool named ‘Aidia’ to support the research and development of medical imaging AI. Aidia offers functionalities such as a medical image viewer, data annotation, model training for various tasks, model evaluation, and automated annotation using trained models. For data annotation, Aidia allows users to annotate images by generating polygons, rectangles, polylines, lines, and points. Aidia supports Digital Imaging and Communications in Medicine images as well as general image formats, and we optimized it for annotating medical images. Moreover, Aidia utilizes open-source Python and PyQt5 libraries to build a cross-platform graphical user interface. Thus, Aidia provides a platform where medical professionals can develop, evaluate, and create training data for AI models at no cost. In this study, we developed a segmentation model based on U-Net to predict mandibular canals in cross-sectional jawbone images using Aidia. We collected 8,287 images annotated by a radiologist and trained the segmentation model using these data. The trained model achieved a precision of 0.805, recall of 0.752, F1 score of 0.777, and average precision of 0.869 on test data, accurately generating training data for the test images. Aidia is a promising solution for AI development and image annotation in the medical field.journal articl
Pneumolysin contributes to dysfunction of nasal epithelial barrier for promotion of pneumococcal dissemination into brain tissue
Get PDFStreptococcus pneumoniae is one of the major pathogens responsible for bacterial meningitis and neurological sequelae. The present study was conducted to identify a non-hematogenous route used by S. pneumoniae to gain access to brain tissue without causing bacteremia or pneumonia, as well as bacterial and host factors involved in this process. To investigate the molecular mechanisms and dissemination pathways of pneumococcal infection in brain tissue, mice were intranasally inoculated with S. pneumoniae strain EF3030, a clinical isolate from a patient with otitis media. Pneumococci were isolated from the frontal olfactory bulb, caudal cerebrum, and cerebellum, with neither bacteremia nor pneumonia observed in the present model. Immunostaining imaging revealed the presence of S. pneumoniae organisms in olfactory nerve fibers. Knockout of the ply gene encoding pneumolysin (PLY) markedly compromised the ability of the bacterial organisms to disseminate into brain tissue, whereas the dissemination efficiency of the complemented strain was restored to nearly the same level as the wild type. Notably, distinct upregulation of Gli1 and Snail1, which are involved in the transcriptional repression of junctional proteins, along with downregulation of E-cadherin, was detected in nasal lavage samples from mice infected with the wild-type or complemented strain, but not in those from mice infected with the ply mutant. Taken together, the present findings indicate that PLY induces Gli1-Snail1-dependent dysfunction of the nasal epithelial barrier, thus allowing pneumococcal dissemination to brain tissue that occurs in a non-hematogenous manner.journal articl
ひきこもり状態となった社員は上司・同僚からどのような印象や態度を抱かれやすいか : 一般企業の管理職・非管理職を対象としたビネット調査から
No full textHikikomori is a Japanese term meaning “pulling inward.” It refers to social withdrawal and has become an urgent social issue in Japan that must be addressed. Support from people around the affected individuals is crucial for accelerating their return to social participation and a more meaningful life; however, prejudice and an incorrect understanding of hikikomori still exists. When those who suffer from social withdrawal try to find employment, or return to work, understanding and cooperation from supervisors and colleagues are essential. However, most work environments are not prepared to accept employees with mental-health problems. Therefore, individuals’ impressions of Hikikomori in an office environment must be examined. This study used a vignette case study and presented participants with a vignette describing an employee who suffered from social withdrawal. The results showed that both supervisors and colleagues generally tended to have positive impressions and attitudes toward individuals with Hikikomori.departmental bulletin pape
A 2-year longitudinal study examining the change in psychosocial factors under the COVID-19 pandemic in Japan
No full textTo examine changes in individuals’ psychosocial variables (e.g., psychological distress, social isolation, and alcohol use) during the prolonged COVID-19 pandemic, a two-year longitudinal survey was conducted at approximately one-year intervals between May 2020 and May 2022, after the first COVID-19-related state of emergency was announced in Japan. The online survey was conducted on May 11-12, 2020 (Phase 1), June 14–20, 2021 (Phase 2), and May 13–30, 2022 (Phase 3). The survey in Phase 1 was conducted during the first emergency declaration period, the survey in Phase 2 was conducted during the third emergency declaration period, and the survey in Phase 3 was conducted at a time when there was no state of emergency but many COVID-19 positive cases. Notably, 3,892 participants responded to all three surveys. In addition to psychosocial inventories often used worldwide, survey items included lifestyle and stress management indicators related to COVID-19 and various sociodemographic items including occupation (e.g., healthcare workers) or income, history of medical treatment for mental problems, severe physical illnesses, and COVID-19.journal articl
Japanese clinical practice guidelines for oral cancer, 2023
No full textThe Japanese Society of Oral Oncology and Japanese Society of Oral and Maxillofacial Surgeons have jointly developed clinical practice guidelines for oral cancer (oral squamous cell carcinoma) to improve and standardize the quality of oral cancer treatment in Japan. The first, second, and third editions were published in 2009, 2013, and 2019, respectively, and the 2023 edition was recently developed. In the development of the 2023 edition, 60 clinical questions (CQs) were listed. Systematic reviews following the GRADE approach were performed for 11 of these CQs. This article outlines the 2023 edition and describes the most relevant guidelines and CQs for the diagnosis, treatment, follow-up, and supportive care of oral cancer patients in Japan.journal articl
Adaptive gene expression of alternative splicing variants of PGC-1α regulates whole-body energy metabolism
No full textThe transcriptional coactivator PGC-1α has been implicated in the regulation of multiple metabolic processes. However, the previously reported metabolic phenotypes of mice deficient in PGC-1α have been inconsistent. PGC-1α exists as multiple isoforms, including variants transcribed from an alternative first exon. We show here that alternative PGC-1α variants are the main entity that increases PGC-1α during exercise. These variants, unlike the canonical isoform of PGC-1α, are robustly upregulated in human skeletal muscle after exercise. Furthermore, the extent of this upregulation correlates with oxygen consumption. Mice lacking these variants manifest impaired energy expenditure during exercise, leading to the development of obesity and hyperinsulinemia. The alternative variants are also upregulated in brown adipose tissue in response to cold exposure, and mice lacking these variants are intolerant of a cold environment. Our findings thus indicate that an increase in PGC-1α expression, attributable mostly to upregulation of alternative variants, is pivotal for adaptive enhancement of energy expenditure and heat production and thereby essential for the regulation of whole-body energy metabolism.journal articl