Development of a glue-free bimorph mirror for use in vacuum chambers

PZT (lead zirconate titanate)-glued bimorph deformable mirrors are widely used in hard X-ray regimes; however, they have not yet been used in soft X-ray regimes because they are less compatible for usage under high vacuum. In this study, we developed a glue-free bimorph deformable mirror, in which silver nano-particles were employed to bond PZT actuators to mirror substrates. Under an appropriate bonding condition, the bonding layer was confirmed to be uniform and the mirror's bending characteristics were demonstrated to be sufficiently stable; its gas emission rate was also shown to be acceptable. Piezo responses before and after additional heating at 200 °C showed the thermal stability of its bonding and bending properties.Yoshio Ichii, Hiromi Okada, Hiroki Nakamori, Akihiko Ueda, Hiroyuki Yamaguchi, Satoshi Matsuyama, and Kazuto Yamauchi, "Development of a glue-free bimorph mirror for use in vacuum chambers", Review of Scientific Instruments 90, 021702 (2019), https://doi.org/10.1063/1.5066105

Hard X-ray nanofocusing using adaptive focusing optics based on piezoelectric deformable mirrors

An adaptive Kirkpatrick-Baez mirror focusing optics based on piezoelectric deformable mirrors was constructed at SPring-8 and its focusing performance characteristics were demonstrated. By adjusting the voltages applied to the deformable mirrors, the shape errors (compared to a target elliptical shape) were finely corrected on the basis of the mirror shape determined using the pencil-beam method, which is a type of at-wavelength figure metrology in the X-ray region. The mirror shapes were controlled with a peak-to-valley height accuracy of 2.5 nm. A focused beam with an intensity profile having a full width at half maximum of 110 × 65 nm (V × H) was achieved at an X-ray energy of 10 keV.Takumi Goto, Hiroki Nakamori, Takashi Kimura, Yasuhisa Sano, Yoshiki Kohmura, Kenji Tamasaku, Makina Yabashi, Tetsuya Ishikawa, Kazuto Yamauchi, and Satoshi Matsuyama, "Hard X-ray nanofocusing using adaptive focusing optics based on piezoelectric deformable mirrors", Review of Scientific Instruments 86, 043102 (2015) https://doi.org/10.1063/1.4916617

Experimental and simulation study of undesirable short-period deformation in piezoelectric deformable x-ray mirrors

To construct adaptive x-ray focusing optics whose optical parameters can be varied while performing wavefront correction, ultraprecise piezoelectric deformable mirrors have been developed. We computationally and experimentally investigated undesirable short-period deformation caused by piezoelectric actuators adhered to the substrate during mirror deformation. Based on the results of finite element method analysis, shape measurements, and the observation of x-ray reflection images, a guideline is developed for designing deformable mirrors that do not have short-period deformation errors. © 2012 American Institute of Physics.Hiroki Nakamori, Satoshi Matsuyama, Shota Imai, Takashi Kimura, Yasuhisa Sano, Yoshiki Kohmura, Kenji Tamasaku, Makina Yabashi, Tetsuya Ishikawa, and Kazuto Yamauchi, "Experimental and simulation study of undesirable short-period deformation in piezoelectric deformable x-ray mirrors", Review of Scientific Instruments 83(5), 053701 (2012) https://doi.org/10.1063/1.4709499

噛ミング30学習による小学生の咀嚼の習慣と口腔内状態に関する介入研究

The aim of this study was to investigate the relationship between chewing behavior and oral conditions in elementary school children based on an intervention study. The subjects were allocated into an intervention group (5th grade students, n=81) and a control group (5th grade students, n=39) in 2 elementary schools in Tokushima Prefecture, Japan. Eating habits were self-reported using a questionnaire in both groups. The PMA index (Schour-Massler index) of each subject in the intervention group was assessed. The school lunch program “Chewing 30” was performed 5 times per year using a chewing counter. After the completion of the program, a significant difference in behavior change regarding “sufficient chewing” was observed between the intervention and control groups (p<0.01). The participants in the intervention group were sub-divided into 2 groups based on the change of “sufficient chewing”. The PMA index of the non-improved group significantly increased (p<0.05), while that of the improved group showed no significant difference. These results suggest an association between insufficient chewing behavior and gingival inflammation in elementary school children. The program “Chewing 30” might be effective to prevent gingival inflammation in addition to promoting sufficient chewing.　本研究では，小学生の咀嚼習慣と口腔内状態との関連性を介入研究にて調査することを目的とした． 　徳島県内にある2つの小学校のうち，1校の5年生（81名）を介入群とし，他校の5年生（39名）をコントロール群として，食習慣に関する保健調査を実施した．介入群では，児童それぞれのPMA index（Schour-Massler index）を評価した．さらに，1年間を通して計5回学校給食時に咀嚼計を用いた「噛ミング30学習」を実施した． 　介入終了後，“よく嚙む” 項目においてコントロール群と介入群では有意な差が認められた（p<0.01）．“よく嚙む” 項目の変化の有無により，介入群を2つのグループに分類した．“よく嚙む” 項目の非改善群ではPMA index中央値が有意に増加していた（p<0.05）が，改善群ではPMA index中央値の増加は認められなかった． 　これらの結果は，小学生において，不十分な咀嚼習慣と歯肉の炎症に関連性があることを示している．「噛ミング30学習」は，よく嚙むことを促すだけでなく，歯肉炎の予防にも効果がある可能性が示唆された

Development of precision Wolter mirrors for future solar x-ray observations

Taro Sakao, Satoshi Matsuyama, Ayumi Kime, Takumi Goto, Akihiko Nishihara, Hiroki Nakamori, Kazuto Yamauchi, Yoshiki Kohmura, Akira Miyake, Hirokazu Hashizume, Tadakazu Maezawa, Yoshinori Suematsu, and Noriyuki Narukage "Development of precision Wolter mirrors for future solar x-ray observations", Proc. SPIE 9603, Optics for EUV, X-Ray, and Gamma-Ray Astronomy VII, 96030U (4 September 2015); https://doi.org/10.1117/12.2188905

Minimum Clinically Important Differences in Oswestry Disability Index Domains and Their Impact on Adult Spinal Deformity Surgery

Study Design Retrospective study. Purpose To calculate the minimum clinically important difference (MCID) for total and individual domains of the Oswestry Disability Index (ODI) and assess score distribution and changes over time in surgically treated adult spinal deformity (ASD) patients. Overview of Literature Despite the common use of ODI for assessing ASD, there are no robust studies defining MCID values for this index. Methods This study included 240 consecutive ASD patients with a minimum of 2 years of follow-up. We calculated MCID values for total and individual ODI domains using all or part of the Scoliosis Research Society-22R questionnaire as anchors. Using current MCID values, we measured the acquisition rates in patients who acquired MCID at follow-up in both total and individual ODI domains. Differences in pathology, age, and locations of the upper and lower instrumented vertebrae were analyzed. Results MCID of the total ODI score was 11%, with an area under the curve of 0.737. Each domain ranged from 0 to 2, with 1 being the most common value. In the pain and standing domains, >60% of the patients acquired MCID, although acquisition rates of the personal care, lifting, sleep, and sexual activity domains were relatively low (20%–35%). Patients with MCID had more radiographic improvement in lumbar lordosis, sagittal vertical axis, and T1 pelvic angle than those without MCID (p<0.05). Conclusions To our knowledge, this is the first study to describe MCID of ODI (11%) after ASD surgery. In the pain and standing domains, most patients acquired MCID although the rates of acquisition of MCID in the personal care, lifting, sleep, and sexual activity domains were low. Spine surgeons should counsel their patients regarding the benefits and setbacks of ASD surgery

Transcranial Motor Evoked Potential Monitoring for the Detection of Nerve Root Injury during Adult Spinal Deformity Surgery

Study Design Retrospective study. Purpose We aimed to determine the utility of transcranial motor evoked potential (TcMEP) monitoring for the detection of intraoperative nerve root injury. Overview of Literature Intraoperative neuromonitoring is important for the prediction of neurological injuries or postoperative paralysis. Nerve root injury can develop as a complication of adult spinal deformity (ASD) surgery. Methods We analyzed 295 patients who underwent ASD surgery using multi-channel TcMEP monitoring between 2010 and 2016 (58 men, 237 women; median age, 68 years; follow-up period ≥1 year). We defined the alarm point as a TcMEP amplitude 17.5° in PT (odds ratio, 17.5; 95% confidence interval, 1.994–153.560; p =0.010) was independently associated with intraoperative nerve root injury. Conclusions Multi-channel TcMEP monitoring may be useful for detecting nerve root injuries. A change in PT of >17.5° may be a significant risk factor for neurological events related to intraoperative nerve root injury