Publications by authors named "Hirotaka Nakamura"

The motion of line defects (dislocations) has been studied for more than 60 years, but the maximum speed at which they can move is unresolved. Recent models and atomistic simulations predict the existence of a limiting velocity of dislocation motion between the transonic and subsonic ranges at which the self-energy of dislocation diverges, though they do not deny the possibility of the transonic dislocations. We used femtosecond x-ray radiography to track ultrafast dislocation motion in shock-compressed single-crystal diamond.

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Objective: The present trial aimed to prove the non-inferiority of the analgesic efficacy of continuous wound infiltration (CWI) to that of continuous intravenous fentanyl (IV) and to compare the safety of the two methods.

Methods: This trial was a prospective, single-centre, two-arm, non-inferiority, randomised controlled trial. Patients participating in the trial were randomised to a CWI group or an IV group.

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Laser-induced periodic surface structure (LIPSS), which has a period smaller than the laser wavelength, is expected to become a potential technique for fine surface processing. We report the microscopic and macroscopic observations of the crystallinity of LIPSSs, where the characteristics such as defects generation and residual strain were analyzed, respectively. The LIPSSs were formed on a Si substrate using two different femtosecond pulses from Ti:Sapphire laser with near-infrared wavelength (0.

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We fabricated an optical transmitter with high frequency and integrated design based on the flip-chip interconnection technique (Hi-FIT) and assisted extended reach electroadsorption modulator integrated distributed feedback (EADFB) laser (AXEL) for 200-Gbit/s/λ application. The Hi-FIT makes it possible to increase modulation bandwidth thanks to wire-free interconnection and peaking control techniques while the AXEL can increase the optical modulation output power thanks to an integrated semiconductor optical amplifier (SOA). The fabricated Hi-FIT AXEL transmitter has a 3-dB bandwidth of more than 66 GHz.

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The European LeukemiaNet (ELN) criteria define the adverse genetic factors of acute myeloid leukemia (AML). AML with adverse genetic factors uniformly shows resistance to standard chemotherapy and is associated with poor prognosis. Here, we focus on the biological background and real-world etiology of these adverse genetic factors and then describe a strategy to overcome the clinical disadvantages in terms of targeting pivotal molecular mechanisms.

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Article Synopsis
  • The study focuses on how social participation affects happiness among older adults in the context of building age-friendly cities (AFCs) in Japan, using data from a large-scale study over several years.
  • It analyzes data from 442,079 older individuals across 289 municipalities, using advanced statistical models to account for various influencing factors.
  • The findings indicate that greater social participation generally leads to increased happiness, highlighting the importance of community engagement in the development and assessment of AFC initiatives.
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Adult T-cell leukemia/lymphoma (ATLL) with extranodal lesions in the head and neck region is rare, with only a few cases reported so far. To our knowledge, this the first case reported involving the hypopharynx. The patient in this case was a 49-year-old woman who presented to an otolaryngology clinic complaining of an abnormal sensation in the throat and difficulty in swallowing.

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Background: Contingent vibratory feedback stimuli applied by a specially designed oral appliance (OA) have been reported to be effective in reducing sleep bruxism (SB). However, the inhibitory effects of the OA, which occur immediately after OA delivery, may have confounded this finding.

Objective: This study sought to shed light on the effects of vibratory stimuli on SB after the OA adaptation period, when its inhibitory effects are diminished.

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An 80 year old male who had received immunosuppressive therapy for myelodysplastic syndrome presented with fever, fatigue, and elevated serum Aspergillus antigen. Computed tomography revealed infiltrative shadows in the left lower lung and subcutaneous nodules. A polymerase chain reaction assay from lung and subcutaneous nodule samples identified the presence Aspergillus udagawae.

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A 72-year-old man with leukocytosis, anemia, and lymphadenopathy was diagnosed with chronic lymphocytic leukemia (CLL) in August 2017 and was carefully monitored in a "watch-and-wait" manner until it became an "active disease." Ibrutinib (IBR) was initiated orally in July 2018 at a dose of 420 mg/day after disease progression due to chromosome 17p deletion (del 17p). The patient showed partial response after transient lymphocytosis while on IBR treatment.

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Staging laser wake-field acceleration is considered to be a necessary technique for developing full-optical jitter-free high energy electron accelerators. Splitting of the acceleration length into several technical parts and with independent laser drivers allows not only the generation of stable, reproducible acceleration fields but also overcoming the dephasing length while maintaining an overall high acceleration gradient and a compact footprint. Temporal and spatial coupling of pre-accelerated electron bunches for their injection in the acceleration phase of a successive laser pulse wake field is the key part of the staging laser-driven acceleration.

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To meet the 5G mobile traffic demands, many small cells will be installed in the field. A promising candidate for reducing a large number of optical fibers connecting the central and distribution units is a tunable wavelength division multiplexing passive optical network. However, for systems in which multiple wavelengths are transmitted densely such as 100 GHz channel spacing, wavelength setting error and wavelength drift are major issues.

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Background/purpose: The onset and progression of periodontitis involve bacterial infection and the immune response. T cells function in the immune response and reportedly induce bone resorption in inflammatory bone loss. However, the exact role of T cells in periodontal destruction remains unclear.

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Purpose: Although sleep bruxism (SB) is one of the most important clinical problems in dental practice, there is no definitive method for controlling it. This pilot study evaluated the effects of contingent vibratory feedback stimuli using an occlusal splint for inhibition of sleep bruxism.

Methods: Thirteen subjects with clinically diagnosed SB participated after providing an informed consent.

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This paper proposes an eye-movement independent brain computer interface based on the modulations of auditory steady-state response (ASSR-BCI) to amplitude-modulated (AM) tones elicited by paying selective attention to one of the two AM tones. Moreover, the proposed ASSR-BCI exploits a stochastic resonance effect to improve the signal separation and attained the mean classification accuracy of 77 % across nine normal subjects under a noise-added condition with sound pressures 60 dB for the two tones and 30 dB for the noise added to the two AM tones. Results from information transfer rate and its inter-individual difference suggest that it may be adequate to set an inter-trial interval at 2∽3 s for a trial time length.

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Interaction of relativistically intense axisymmetrically polarized (radially or azimuthally polarized) laser pulses (RIAPLP) with underdense plasma is shown experimentally and theoretically to be essentially different from the interaction of conventional Gaussian pulses. The difference is clearly observed in distinct spectra of the side-scattered laser light for the RIAPLP and Gaussian pulses, as well as in the appearance of a spatially localized strong side emission of second harmonic of the laser pulse in the case of RIAPLP. According to our analysis based on three-dimensional particle-in-cell simulations, this is a result of instability in the propagation of RIAPLP in uniform underdense plasma.

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The aim of this study was to investigate the association between patterns of jaw motor activity during sleep and clinical signs and symptoms of sleep bruxism. A total of 35 university students and staff members participated in this study after providing informed consent. All participants were divided into either a sleep bruxism group (n = 21) or a control group (n = 14), based on the following clinical diagnostic criteria: (1) reports of tooth-grinding sounds for at least two nights a week during the preceding 6 months by their sleep partner; (2) presence of tooth attrition with exposed dentin; (3) reports of morning masticatory muscle fatigue or tenderness; and (4) presence of masseter muscle hypertrophy.

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Background And Objective: There are a few experimental models that clearly describe the pathological differences in tissue destruction between periodontitis and peri-implantitis. We recently reported that the formation of immune complexes accelerates site-specific loss of attachment and alveolar bone resorption when an antigen is topically applied in the gingival sulcus of an immunized rat. We applied this model to the peri-implant tissues and compared peri-implant destruction to periodontitis without using a ligature.

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Background: Osteoclasts differentiated from bone marrow macrophages (BMMs) induced by TNF-α alone do not have resorbing activity. When BMMs are stimulated with receptor activator of NF-κB ligand (RANKL) before TNF-α stimulation, pit-forming osteoclasts are differentiated. However, the details of the effect of RANKL pretreatment on the pit-forming osteoclast differentiation by TNF-α have not been established.

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This paper describes the demonstration of an energy efficient orthogonal frequency division multiplexing passive optical network using the dynamic signal to noise ratio (SNR) management and adaptive modulation. Controlling the calculation precision and modulation format minimizes the energy consumption of digital signal processor while satisfying the requirements of bit error ratio. We show that the calculation precision and modulation format can be optimized according to the optical received power, and realize a 58.

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