Publications by authors named "Masahiro Iwahashi"

There are three primary objectives of this work; first: to establish a gas concentration map; second: to estimate the point of emission of the gas; and third: to generate a path from any location to the point of emission for UAVs or UGVs. A mountable array of MOX sensors was developed so that the angles and distances among the sensors, alongside sensors data, were utilized to identify the influx of gas plumes. Gas dispersion experiments under indoor conditions were conducted to train machine learning algorithms to collect data at numerous locations and angles.

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Background: Monitoring jar fermenter-cultured microorganisms in real time is important for controlling productivity of bioproducts in large-scale cultivation settings. Morphological data is used to understand the growth and fermentation states of these microorganisms during monitoring. Oleaginous yeasts are used for their high productivity of single-cell oils but the relationship between lipid productivity and morphology has not been elucidated in these organisms.

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This article presents a method for trend clustering from tweets about coronavirus disease (COVID-19) to help us objectively review the past and make decisions about future countermeasures. We aim to avoid detecting usual trends based on seasonal events while detecting essential trends caused by the influence of COVID-19. To this aim, we regard daily changes in the frequencies of each word in tweets as time series signals and define time series signals with single peaks as target trends.

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This article presents a method that detects tweet communities with similar topics and ranks the communities by . By identifying the tweet communities that have high importance measures, it is possible for users to easily find important information about the coronavirus disease (COVID-19). Specifically, we first construct a community network, whose nodes are tweet communities obtained by applying a community detection method to a tweet network.

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This paper proposes a method for classifying the river state (a flood risk exists or not) from river surveillance camera images by combining patch-based processing and a convolutional neural network (CNN). Although CNN needs much training data, the number of river surveillance camera images is limited because flood does not frequently occur. Also, river surveillance camera images include objects that are irrelevant to the flood risk.

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The aim of this study was to elucidate the long-term results of crossover bypass (CB) for iliac atherosclerotic lesions in the era of endovascular treatment (EVT). A retrospective multicenter cohort study was performed. CB was performed in 242 patients between 2003 and 2014 by vascular surgeons at multiple medical centers in Japan.

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Various somatic stem cells divide asymmetrically; however, it is not known whether embryonic stem cells (ESCs) divide symmetrically or asymmetrically, not only while maintaining an undifferentiated state but also at the onset of differentiation. In this study, we observed single ESCs using time-lapse imaging and compared sister cell pairs derived from the same mother cell in either the maintenance or differentiation medium. Mouse ESCs were cultured on E-cadherin-coated glass-based dishes, which allowed us to trace single cells.

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Brain electrical activity recordings by electroencephalography (EEG) are often contaminated with signal artifacts. Procedures for automated removal of EEG artifacts are frequently sought for clinical diagnostics and brain-computer interface applications. In recent years, a combination of independent component analysis (ICA) and discrete wavelet transform has been introduced as standard technique for EEG artifact removal.

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This study proposes a method to evaluate the electric field induced in the brain by transcranial magnetic stimulation (TMS) to realize focal stimulation in the target area considering the inter-subject difference of the brain anatomy. The TMS is a non-invasive technique used for treatment/diagnosis, and it works by inducing an electric field in a specific area of the brain via a coil-induced magnetic field. Recent studies that report on the electric field distribution in the brain induced by TMS coils have been limited to simplified human brain models or a small number of detailed human brain models.

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We performed a retrospective analysis of patients with diffuse large B cell lymphoma treated with rituximab plus CHOP (cyclophosphamide, adriamycin, vincristine and prednisone) as a first-line therapy at 22 hospitals of the Kyushu Lymphoma Study Group. During the period 1996-2005, 1,057 patients (aged 22-90 years) were analyzed. Of these, 678 were treated with CHOP, and 379 were treated with rituximab plus CHOP (R-CHOP).

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We evaluated the usefulness of prognostic markers in patients with diffuse large B-cell lymphoma (DLBCL) treated with cyclophosphamide, vincristine, doxorubicin, and prednisolone (CHOP) +/- rituximab (R-CHOP) in Japan. We studied 730 patients with DLBCL; 451 received CHOP and 279 R-CHOP. We analyzed biopsy samples immunohistochemically for markers of germinal center B cells (CD10, Bcl-6), postgerminal center B cells (Multiple myeloma-1), and apoptosis (Bcl-2).

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We report a case of aortic stenosis with porcelain aorta using an apicoaortic valved conduit after 'aortic no touch' off-pump coronary artery bypass grafting. Apicoaortic valved conduit is a good surgical option for this patient to avoid re-entry through the sternum, injury to patent graft and manipulation of the porcelain ascending aorta.

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Mycotic thoracic aortic aneurysm is a fatal disease. We report a case of a 67-year-old man presenting with contained rupture of a mycotic thoracic aortic aneurysm. Urgent in situ graft replacement was successfully performed with omental wrapping to prevent postoperative graft infection.

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The combination of a change in lifestyle toward Western habits and an aging society, has led to a steady increase in the incidence of atherosclerotic diseases in the Japanese population. Coronary artery disease (CAD), carotid stenosis (CS), and peripheral artery disease (PAD) are major manifestations of generalized atherosclerosis and increase the risk of cardiovascular events. However, the incidence of CS and PAD in Japanese patients with CAD is not well known, so the present study investigated this in 380 consecutive patients with CAD undergoing elective coronary aorta bypass grafting (CABG) at Kishiwada Tokushukai Hospital between October 1999 and October 2001.

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