135 results on '"Yohei, Suzuki"'
Search Results
2. Massive nitrogen supersaturation to CoCrMo alloys for surface microstructure control
- Author
-
Tatsuhiko Aizawa, Tatsuya Funazuka, Tomomi Shiratori, and Yohei Suzuki
- Subjects
Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
CoCrMo alloys were plasma nitrided at 673 K for 14.4 ks to form a homogeneous nitrided layer with a thickness of 12 μm. This nitrogen-supersaturated layer had an expanded γ-phase with fine CrN precipitates. The nitrogen solute distributed homogeneously with its average content of 5 mass% toward the nitriding front end. This nitrided CoCrMo alloy matrix with its average grain size of 20 μm was plastically strained by the nitrogen supersaturation to significantly modify its original crystallographic microstructure. This nitrided layer consists of intensely textured grains with the orientation of (111) in the normal direction. The nitrided and textured layer had higher hardness 1,620 HV1N than the original polycrystalline CoCrMo matrix, 400 HV1N. Its average friction coefficient against the SUJ2 ball in dry was 0.4–0.5 under the applied load of 5 N and the sliding speed of 0.1 m/s.
- Published
- 2023
- Full Text
- View/download PDF
3. Aqueous column changes in the episcleral veins after the instillation of ripasudil versus latanoprost: a randomized, double-blind, crossover clinical trial
- Author
-
Marie Suzuki, Yohei Suzuki, Ryohei Komori, Yusuke Orii, Shogo Arimura, Kentaro Iwasaki, Yoshihiro Takamura, and Masaru Inatani
- Subjects
Medicine ,Science - Abstract
Abstract To investigate whether the topical administration of ripasudil ophthalmic solution enhances aqueous outflow in the episcleral vein of the human eye. Two-sequence, prospective, randomized, double-blind, crossover trial. Sixteen eyes of 16 healthy participants were recruited in this study. Participants were randomized into one of the two crossover sequences to the instillation of ripasudil or the control drug, latanoprost, followed by a washout period of more than 2 days, and crossed over to the alternative instillation. The aqueous columns in the episcleral veins were recorded using a video capture system connected to a slit-light microscope (hemoglobin video imaging) before and 2 and 8 h after the instillation. Comparisons between ripasudil and latanoprost for the changes of the aqueous column width after the instillation. Two hours after the instillation, the ripasudil group had significantly greater dilation of the aqueous column width than the latanoprost group. Eight hours after the instillation, the ripasudil group had significantly greater dilation of the aqueous column width than the latanoprost group. Hemoglobin video imaging revealed that the topical administration of ripasudil ophthalmic solution enhanced aqueous outflow in the episcleral vein of the human eye.
- Published
- 2022
- Full Text
- View/download PDF
4. Propylene glycol, a component of electronic cigarette liquid, damages epithelial cells in human small airways
- Author
-
Moegi Komura, Tadashi Sato, Hitomi Yoshikawa, Naoko Arano Nitta, Yohei Suzuki, Kengo Koike, Yuzo Kodama, Kuniaki Seyama, and Kazuhisa Takahashi
- Subjects
Airway epithelial cell ,Apoptosis ,Cell cycle ,Chronic obstructive pulmonary disease ,E-cigarette ,E-liquid ,Diseases of the respiratory system ,RC705-779 - Abstract
Abstract Background Electronic cigarettes (e-cigarettes) are used worldwide as a substitute for conventional cigarettes. Although they are primarily intended to support smoking cessation, e-cigarettes have been identified as a gateway to smoking habits for young people. Multiple recent reports have described the health effects of inhaling e-cigarettes. E-cigarette liquid (e-liquid) is mainly composed of propylene glycol (PG) and glycerol (Gly), and the aerosol generated by these devices primarily contains these two components. Thus, this study aimed to evaluate the effects of PG and Gly on human small airway epithelial cells (SAECs). Methods SAECs were exposed to PG or Gly, and cell proliferation, cell viability, lactate dehydrogenase (LDH) release, DNA damage, cell cycle, and apoptosis were evaluated. Additionally, SAECs derived from chronic obstructive pulmonary disease (COPD) patients (COPD-SAECs) were investigated. Results Exposure of SAECs to PG significantly inhibited proliferation (1%, PG, p = 0.021; 2–4% PG, p
- Published
- 2022
- Full Text
- View/download PDF
5. Blood Eosinophil Count as a Predictive Biomarker of Chronic Obstructive Pulmonary Disease Exacerbation in a Real-World Setting
- Author
-
Moegi Komura, Tadashi Sato, Yohei Suzuki, Hitomi Yoshikawa, Naoko Arano Nitta, Mika Hayashi, Eriko Kuwasaki, Kimiko Horikoshi, Toshihiko Nishioki, Mikiko Mori, Yuzo Kodama, Shinichi Sasaki, and Kazuhisa Takahashi
- Subjects
Diseases of the respiratory system ,RC705-779 - Abstract
Introduction. Chronic obstructive pulmonary disease (COPD) is the third leading cause of death, and COPD exacerbation worsens the prognosis. Eosinophilic airway inflammation is a COPD phenotype that causes COPD exacerbation and is correlated with peripheral blood eosinophil count. We analyzed real-world data of COPD patients to assess the risk factors of COPD exacerbation focusing on blood eosinophils. Materials and Methods. Patients with COPD who visited our hospital between January 1, 2018, and December 31, 2018, were recruited, and their background information, spirometry data, laboratory test results, and moderate-to-severe exacerbation events during the one-year follow-up period were collected from the electronic medical records and analyzed. The COPD exacerbation risk factors were assessed using univariate and multivariate logistic regression analyses. Results. Twenty-two of 271 (8.1%) patients experienced moderate-to-severe exacerbation. Patients with exacerbation showed worse pulmonary function, and we found that a high blood eosinophil count (≥350 cells/μL; p=0.014), low % FEV1 (
- Published
- 2023
- Full Text
- View/download PDF
6. The Redox Potential Measurements for Heme Moieties in Variants of D-Fructose Dehydrogenase Based on Mediator-assisted Potentiometric Titration
- Author
-
Yohei SUZUKI, Keisei SOWA, Yuki KITAZUMI, and Osamu SHIRAI
- Subjects
d-fructose dehydrogenase ,potentiometric titration ,heme moieties ,mutations ,Technology ,Physical and theoretical chemistry ,QD450-801 - Abstract
The effect of mutation on the redox potentials (E°′) of the heme moieties in the variants of d-fructose dehydrogenase (FDH) was investigated by mediated spectroelectrochemical titrations. The replacement of the axial ligand of heme from methionine to glutamine changes the E°′ value more negatively than that of the corresponding heme moiety in the recombinant (native) FDH (rFDH). The determined E°′ values of non-targeted heme moieties in the variants were also shifted in a negative direction from that in rFDH. Thus, enzyme modification changes E°′ of the heme moieties in unmodified protein regions.
- Published
- 2021
- Full Text
- View/download PDF
7. A Novel Method for Urinary Tract Reconstruction in Transplanted Embryonic Kidneys Using the Hybrid Stent: A Pig Study
- Author
-
Kenji Matsui, MD, Satomi Iwai, DVM, PhD, Hiroshi Sasaki, MD, PhD, Tsuyoshi Takamura, MD, Yoshitaka Kinoshita, MD, Yatsumu Saito, MD, Toshinari Fujimoto, MD, PhD, Yasuhide Nakayama, PhD, Yohei Suzuki, BE, Hitomi Matsunari, PhD, Hiroshi Nagashima, PhD, Eiji Kobayashi, MD, PhD, and Takashi Yokoo, MD, PhD
- Subjects
Surgery ,RD1-811 - Published
- 2022
- Full Text
- View/download PDF
8. Comparing the Effectiveness of Afatinib and Osimertinib for Patients With PD-L1-positive EGFR-mutant Non-small Cell Carcinoma.
- Author
-
MINEHIKO INOMATA, YOSUKE KAWASHIMA, RYOTA SAITO, DAISUKE MORINAGA, HITOMI NOGAWA, MASAMICHI SATO, YOHEI SUZUKI, SATORU YANAGISAWA, TAKASHI KIKUCHI, DAISUKE JINGU, NARUO YOSHIMURA, TOSHIYUKI HARADA, and EISAKU MIYAUCHI
- Subjects
OSIMERTINIB ,AFATINIB ,EPIDERMAL growth factor ,NON-small-cell lung carcinoma ,KINASE inhibitors - Abstract
Background/Aim: Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are effective for treating non-small cell lung cancer (NSCLC) harboring EGFR mutations. However, higher tumor programmed death ligand-1 (PD-L1) expression is associated with a poor response to EGFR-TKIs, and information on the comparison between afatinib and osimertinib in PD-L1-positive EGFR-mutant NSCLC is scarce. Patients and Methods: We retrospectively analyzed data of patients with PD-L1-positive EGFR-mutant NSCLC to compare the effectiveness of afatinib and osimertinib. Results: A total of 177 patients were included in the study. The Cox proportion hazard model was adjusted for age, sex, performance status, EGFR mutation status, PD-L1 expression level, and brain metastasis, revealing that there was no significant difference in risk for progression [hazard ratio (HR)=0.99, 95% confidence interval (CI)=0.64-1.53] or death (HR=0.96, 95% CI=0.54-1.73) between afatinib and osimertinib. Conclusion: In conclusion, the EGFR-TKI treatment duration and overall survival after the treatment with afatinib or osimertinib were similar in patients with PD-L1- positive EGFR-mutant NSCLC in the present study. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
9. Fabrication of Punch and Die Using Plasma-Assisted 3D Printing Technology for Piercing Sheet Metals
- Author
-
Tatsuhiko Aizawa, Yohei Suzuki, Tomoaki Yoshino, and Tomomi Shiratori
- Subjects
plasma-assisted 3D-printing ,machining-free process ,AISI316L punch and die ,fine piercing ,electrical steel sheets ,clearance control ,Production capacity. Manufacturing capacity ,T58.7-58.8 - Abstract
A pair of punch and die was often fabricated using subtractive manufacturing processes such as milling and other machining processes. However, additive manufacturing could be used to perform the same processes. This study explored this possibility. In particular, this study fabricated a pair of T-shaped punch and die made of AISI316L austenitic stainless steel using an additive manufacturing process called plasma-assisted 3D printing. Accordingly, T-shaped negative and positive 2D patterns were screen-printed onto the mirror-polished surfaces of the substrates made of AISI316L austenitic stainless steel. The printed film worked like a mask to prevent the printed substrate surfaces from nitriding. In order to form a thick nitrided layer, the unprinted substrate surfaces were selectively nitrided at 673 K for 14.4 ks. The un-nitrided segments of the substrates were uniformly removed by sand-blasting that involved shooting silica particles on the substrate’s surfaces. As a result, the substrates printed with negative and positive T-shaped patterns were transformed into the punch head and die cavity. In order to see the efficacy of the fabricated punch and die pair, this pair was used for piercing the electrical steel sheets under a controlled clearance. Scanning Electron Microscopy with Energy Dispersive X-ray (SEM-EDX) was used to measure surface topography after piercing. In addition, SEM and a 3D profilometer were used to measure the punch and die profiles after piercing. The abovementioned measurement results showed that the fabricated punch and die exhibited highly accurate piercing behavior. Thus, the plasma-assisted 3D printing was useful for punch and die fabrication.
- Published
- 2022
- Full Text
- View/download PDF
10. Regional heterogeneity in response of airway epithelial cells to cigarette smoke
- Author
-
Hario Baskoro, Tadashi Sato, Keiko Karasutani, Yohei Suzuki, Aki Mitsui, Naoko Arano, Fariz Nurwidya, Motoyasu Kato, Fumiyuki Takahashi, Yuzo Kodama, Kuniaki Seyama, and Kazuhisa Takahashi
- Subjects
Cigarette smoke ,Airway epithelial cells ,Small airway ,Inflammation ,Cyclooxygenase-2 ,Chronic obstructive pulmonary disease ,Diseases of the respiratory system ,RC705-779 - Abstract
Abstract Background Cigarette smoke (CS) exposure causes an abnormal inflammatory response, which can result in chronic obstructive pulmonary disease (COPD). Previous studies show that this disorder predominantly occurs in peripheral or small-airway areas, whereas the same condition has not been identified in the larger airways during the course of COPD. However, the different biochemical and genetic alterations occurring in response to CS exposure among airway epithelial cells from different sites in the lungs have not been fully investigated. Methods Human small airway epithelial cells (SAECs) and normal human bronchial epithelial cells (NHBEs) were exposed to CS extract (CSE), and microarray analysis was used to determine gene- and protein-expression profiles and identify alterations following CSE exposure in both cell types. An in vivo smoking experiment was also performed to confirm differential responses to CS between sites in the lung. Results Microarray analysis of SAECs and NHBEs following 24 h of CSE exposure showed that inflammatory related pathways and terms, including the tumor necrosis factor-signaling pathway, were overrepresented, especially in SAECs. Clustering analysis highlighted prostaglandin-endoperoxide synthase-2 [also known as cyclooxygenase (COX)-2] as a gene specifically upregulated in SAECs, with COX-2 mRNA and protein expression significantly elevated by CSE exposure in SAECs (3.1- and 3.1-fold, respectively), but not in NHBEs. Furthermore, time-course analysis of COX-2 expression revealed earlier increases in SAECs compared with NHBEs following CS exposure. Short-term exposure of mouse lungs to CS was found to predominantly induce COX-2 expression in the small airway. Conclusions The small airway is more susceptible to CSE than the large airway and could be the initial site of development of CS-related respiratory diseases, such as COPD.
- Published
- 2018
- Full Text
- View/download PDF
11. Effects of Resin Coating on Punching of Amorphous Electrical Steel Sheet Stack
- Author
-
Yukiya KOMORI, Tomoaki YOSHINO, Yohei SUZUKI, Tatsuhiko AIZAWA, and Tomomi SHIRATORI
- Subjects
Mechanics of Materials ,Mechanical Engineering ,General Materials Science - Published
- 2023
- Full Text
- View/download PDF
12. Quantitative Characterization of the Affected Zones in a Single Crystal Fe-6Si Steel Sheet by Fine Piercing
- Author
-
Tatsuhiko Aizawa, Tomomi Shiratori, Tomoaki Yoshino, Yohei Suzuki, and Kuniaki Dohda
- Subjects
motor core ,electrical steel sheet ,single crystal ,plastically affected zone by piercing ,plastic straining ,spinning ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
An iron loss in the motor core was often enhanced by formation of plastically affected zones in piercing the electrical steel sheets. A platform methodology to carry out quantitative evaluation of these affected zones in the pierced electrical steel sheets was proposed to search for the way to minimize the affected zone widths. A coarse-grained electrical steel sheet was employed as a work material for a fine piercing experiment under the narrowed clearance between the plasma-nitrided SKD11 punch and core-die. The shearing behavior by the applied loading for piercing was described by in situ measurement of the load-stroke relationship. The plastic straining in the single-crystal electrical steel sheet was characterized by SEM (scanning electron microscopy) and EBSD (electron back-scattering diffraction) to define the affected zone size and to analyze the rotation of crystallographic orientations by the induced plastic distortion during piercing. Integral and differentiation of spin rotation measured the affected zones. The effect of punch edge sharpness on these spin-rotation measures was also discussed using the nitrided and ion-milled SKD11 punch and core-die.
- Published
- 2022
- Full Text
- View/download PDF
13. Micro-/Nano-Texturing onto Plasma-Nitrided Tool Surface by Laser Printing for CNC Imprinting and Piercing
- Author
-
Tatsuhiko Aizawa, Tomoaki Yoshino, Yohei Suzuki, and Tadahiko Inohara
- Subjects
surface decoration ,laser printing ,micro-nano texturing ,imprinting ,piercing ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
A new data transformation method for micro-manufacturing using a topological model for a micro-/nano-texture was proposed for a surface-decorated product. Femtosecond laser printing was utilized to form the micro-/nano-textures into the hardened thick layer of dies by plasma nitriding. At first, the plasma-nitrided AISI316L flat substrate was laser-printed as a punch to imprint the tailored nano-textures onto the AA1060 aluminum plate for its surface decoration with topological emblems. Second, the plasma-nitrided SKD11 cylindrical punch was laser-trimmed to form the nanostructures on its side surface. This nano-texture was imprinted onto the hole surface concurrently with piercing a circular hole into electrical steel sheet. The fully burnished surface had a shiny, metallic quality due to the nano-texturing. The plasma nitriding, the laser printing and the CNC (computer numerical control) imprinting provided a way of transforming the tailored textures on the metallic product.
- Published
- 2022
- Full Text
- View/download PDF
14. Surgical removal of hearing aid ear mold impression material from the middle ear: a report of two cases
- Author
-
Satoshi Yoshioka, Emiko Inuzuka, Hisayuki Kato, Kensei Naito, Yohei Suzuki, and Tadao Hattori
- Subjects
hearing aid ,ear mold ,impression material ,chronic otitis media ,middle ear foreign body ,Medicine (General) ,R5-920 - Abstract
A hearing aid effectively improves the quality of life of hard-of-hearing people, but complications after obtaining an ear mold to facilitate fitting the hearing aid have been reported. We treated two patients in whom we surgically removed ear mold impression material from the middle ear. The first patient was a 78-year-old man with persistent right otorrhea. He was initially diagnosed with chronic otitis media and was treated conservatively. The otorrhea did not resolve. Further examination revealed a foreign body in the tympanic cavity, which was identified as impression material based on material analysis. The patient then remembered that a mold for a hearing aid ear had been prepared for him about 15 years ago. Tympanoplasty was performed successfully. The second patient (case 2) was an 84-year-old woman who had undergone canal wall down tympanoplasty. Impression material was introduced into her left ear but could not be removed. Foreign body extraction was performed through an incision behind the ear, with the impression material found embedded in the mastoid cavity. It was successfully removed. In both cases, we considered it crucial to obtain the patient’s medical history, thoroughly examine the tympanic membrane, be aware of the risk associated with hearing aid fitting in a postoperative ear, and avoid injecting impression material to aid hearing aid fitting without careful consideration.
- Published
- 2017
- Full Text
- View/download PDF
15. Femtosecond Laser Trimming with Simultaneous Nanostructuring to Fine Piercing Punch to Electrical Amorphous Steel Sheets
- Author
-
Tatsuhiko Aizawa, Tomomi Shiratori, Yoshihiro Kira, Tomoaki Yoshino, and Yohei Suzuki
- Subjects
fine piercing ,electrical amorphous steel sheets ,induced damages by piercing ,diamond coated punch ,edge width ,edge profile ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
A CVD (Chemical Vapor Deposition) diamond coated tungsten carbide (WC) and cobalt (Co) sintered alloy punch was trimmed by the femtosecond laser machining to sharpen its edge with about 2 μm and to simultaneously make nanostructuring to its side surface. In addition to the sharpened edge, its edge profile was formed to be homogeneous enough to reduce the damage layer width by piercing the electrical amorphous steel sheet stack. Each brittle sheet in the stacked work was damaged to have three kinds of defects by piercing; e.g., the droop-like cracking in the thickness and at the vicinity of hole, the wrinkling in peak-to-valley with partial cracking on the peaks, and the circumferential cracking. When using the WC (Co) punch with the inhomogeneous edge profile in the sharpened edge width, these three damages were induced into each sheet and the maximum damage width exceeded 80 μm. When using the punch with the sharpened edge and homogeneous edge profile, the wrinkling mode was saved and the total affected layer width was significantly reduced to less than 20 μm. Through the precise embossing experiments, this effect of punch edge profile condition to the induced damages was discussed with a statement on the nanostructuring effect on the reduction of damaged width in electrical amorphous steel sheets. The developed tool with the sharpened edge and homogenous edge condition contributes to the realization of a low iron loss motor with a reduced affected layer width.
- Published
- 2021
- Full Text
- View/download PDF
16. Anti-Galling Cold, Dry Forging of Pure Titanium by Plasma-Carburized AISI420J2 Dies
- Author
-
Tatsuhiko Aizawa, Tomoaki Yoshino, Yohei Suzuki, and Tomomi Shiratori
- Subjects
low-temperature plasma carburizing ,high surface hardness ,carbon supersaturation ,dry, cold forging ,high reduction in thickness ,free carbon isolation ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
A bare AISI420J2 punch often suffers from severe adhesion of metallic titanium as well as titanium oxide debris particles in dry, cold forging of biomedical titanium alloys. This punch was plasma-carburized at 673 K for 14.4 ks to harden it up to 1200 HV on average and to achieve carbon supersaturation in the carburized layer. This plasma-carburized punch was employed in the cold, dry forging of a pure titanium wire into a flat plate while reducing the thickness by 70%. The contact interface width approached the forged workpiece width with increasing the reduction ratio. This smaller bulging deformation reveals that the workpiece is upset by homogeneous plastic flow with a lower friction coefficient. This low-friction and anti-galling forging process was sustained by an in situ solid lubrication mechanism. Unbound free carbon was isolated from the carbon-supersaturated AISI420J2 matrix and deposited as a thin tribofilm to protect the contact interface from mass transfer of metallic titanium.
- Published
- 2021
- Full Text
- View/download PDF
17. Multiple electron transfer pathways of tungsten-containing formate dehydrogenase in direct electron transfer-type bioelectrocatalysis
- Author
-
Tatsushi Yoshikawa, Fumiaki Makino, Tomoko Miyata, Yohei Suzuki, Hideaki Tanaka, Keiichi Namba, Kenji Kano, Keisei Sowa, Yuki Kitazumi, and Osamu Shirai
- Subjects
Electron Transport ,Materials Chemistry ,Metals and Alloys ,Ceramics and Composites ,Electrons ,General Chemistry ,Electrodes ,Formate Dehydrogenases ,Tungsten ,Catalysis ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials - Abstract
Tungsten-containing formate dehydrogenase from Methylorubrum extroquens AM1 (FoDH1) was investigated from structural biology and bioelectrochemistry. The electron transfer (ET) pathways were investigated by structural information, electrostatic interactions between the electrode and the enzyme, and the differences in the substrates. Two electrode-active sites and multiple ET pathways in FoDH1 were discovered.
- Published
- 2022
- Full Text
- View/download PDF
18. Consideration of Phase Transformation due to High Stress Amplitude of Ultrafine Grain SUS304 Steel
- Author
-
Noriyasu OGUMA, Shota OIKAWA, Masaki OKANE, Yohei SUZUKI, Satoru HIRABAYASI, and Takafumi KOMATSU
- Subjects
General Medicine - Published
- 2022
- Full Text
- View/download PDF
19. Adaptive Parameter Adjustment of a Real-Time SPH Simulation for Interactive Virtual Environments: Application to Parallel Processing.
- Author
-
Masayuki Kawai and Yohei Suzuki
- Published
- 2012
- Full Text
- View/download PDF
20. Sampling Rate Selection Path Diversity for a RAKE Receiver in DS/SS.
- Author
-
Yohei Suzuki, Anas Muhamad Bostamam, Mamiko Inamori, and Yukitoshi Sanada
- Published
- 2008
- Full Text
- View/download PDF
21. Experimental Investigation of Channel Estimation for IEEE802.11b WLAN System.
- Author
-
Yu Imaoka, Hiroshi Obata, Yohei Suzuki, and Yukitoshi Sanada
- Published
- 2007
- Full Text
- View/download PDF
22. Plasma Nitriding-Assisted 3D Printing for Die Technology in Digital Micro-Manufacturing
- Author
-
Tatsuhiko Aizawa, Tomomi Shiratori, and Yohei Suzuki
- Abstract
A plasma nitriding-assisted 3D printing method was developed to build up the micro-punch and micro-die systems. Two dimensional punch head and core-die cavity geometries were ink-jet printed or screen-printed onto the AISI316 and SKD11 tool substrate surfaces in following their two-dimensional computer-aided design (CAD) data. The low-temperature plasma nitriding process was utilized to make nitrogen supersaturation only into the unprinted substrates. The sand-blasting and chemical etching were utilized to mechanically or chemically remove the printed parts from punch and die substrate. As sand-blasted and chemically etched AISI316 and SKD11 punches and core-dies were simply finished and used as a die set for micro-embossing, micro-piercing and micro-punching processes. In particular, a micro-pump was selected as a miniature mechanical element. Its 3D CAD geometry was sliced to 2D CAD data for each functional AISI304 stainless steel sheet. A pair of punch and die for each 2D CAD geometry for constituent sheet was prepared by the plasma nitriding-assisted 3D printing. Each sheet was punched out by using this set of punch and die to functionalize each sheet unit in correspondence to the sliced CAD data. These constituent sheets were assembled and joined to a structural unit of micro-pump.
- Published
- 2022
23. p19Arf Exacerbates Cigarette Smoke-Induced Pulmonary Dysfunction
- Author
-
Ryuta Mikawa, Tadashi Sato, Yohei Suzuki, Hario Baskoro, Koichiro Kawaguchi, and Masataka Sugimoto
- Subjects
p19arf ,senescence ,senolysis ,emphysema ,copd ,Microbiology ,QR1-502 - Abstract
Senescent cells accumulate in tissues during aging or pathological settings. The semi-genetic or pharmacological targeting of senescent cells revealed that cellular senescence underlies many aspects of the aging-associated phenotype and diseases. We previously reported that cellular senescence contributes to aging- and disease-associated pulmonary dysfunction. We herein report that the elimination of Arf-expressing cells ameliorates cigarette smoke-induced lung pathologies in mice. Cigarette smoke induced the expression of Ink4a and Arf in lung tissue with concomitant increases in lung tissue compliance and alveolar airspace. The elimination of Arf-expressing cells prior to cigarette smoke exposure protected against these changes. Furthermore, the administration of cigarette smoke extract lead to pulmonary dysfunction, which was ameliorated by subsequent senescent cell elimination. Collectively, these results suggest that senescent cells are a potential therapeutic target for cigarette smoking-associated lung disease.
- Published
- 2020
- Full Text
- View/download PDF
24. Impaired psychomotor vigilance associated with sleep-disordered breathing in women working in the care of older adults in Japan
- Author
-
Ai Ikeda, Ronald Filomeno, Yasunari Koyama, Yohei Suzuki, Satomi Ikeda, Yuka Suzuki, Yumi Hashimoto, Takeshi Tanigawa, Hiroo Wada, Narihisa Miyachi, and Koutatsu Maruyama
- Subjects
Psychomotor learning ,medicine.medical_specialty ,Neurology ,business.industry ,media_common.quotation_subject ,Psychomotor vigilance task ,03 medical and health sciences ,0302 clinical medicine ,030228 respiratory system ,Otorhinolaryngology ,mental disorders ,Ambulatory ,Respiratory disturbance index ,Physical therapy ,Breathing ,Medicine ,Neurology (clinical) ,business ,Body mass index ,030217 neurology & neurosurgery ,Vigilance (psychology) ,media_common - Abstract
With a rapidly aging society, there is increasing interest in the health of female workers in the field of care services for older adults due to increasing demands to maintain 24-h care and to support older adults without errors or accidents. Therefore, the purpose of this cross-sectional study was to examine the association between sleep-disordered breathing (SDB) and sustained attention in women caring for older adults in Japan. The study was conducted in women aged 18–67 years old working in care service facilities for older adults in Japan. The sustained attention of participants was measured by the 10-min psychomotor vigilance task (PVT). SDB was assessed based on the respiratory disturbance index (RDI), which was measured using an ambulatory airflow monitor with a polyvinylidene fluoride (PVDF) film sensor to monitor the respiratory airflow of nasal and oral breathing. The participants wore the monitor to record the breathing status while asleep at home. The severity of SDB was categorized as follows: normal, RDI
- Published
- 2021
- Full Text
- View/download PDF
25. Nitrogen Supersaturation of AISI316 Base Stainless Steels at 673 K and 623 K for Hardening and Microstructure Control
- Author
-
Tatsuhiko, Aizawa, Tomomi, Shiratori, Tomoaki, Yoshino, Yohei, Suzuki, and Takafumi, Komatsu
- Abstract
The high-density plasma nitriding at 673 K and 623 K was employed to make 10% of nitrogen supersaturation on AISI316 base austenitic stainless steels. The processing parameters and nitrogen-hydrogen gas flow ratio were optimized to increase the yield of N2+ ion and NH-radical for efficient nitriding. The nitrided AISI316 specimens were prepared for multidimensional analysis to describe the fundamental features of low-temperature plasma nitriding. First, macroscopic evaluation revealed that nitrogen supersaturation induced the γ-lattice expansion and the higher nitrogen content than 4% of mass in depth. The mesoscopic analysis describes the holding temperature and initial grain-size effects on the microstructure changes. Plastic straining, grain-size refinement, and nitrogen zone-boundary diffusion processes advance with nitrogen supersaturation to drive the inner nitriding behavior. The microscopic analysis explains the microstructure refinement, the two-phase structuring, and the microstructure modification. Through this multi-dimensional analysis, the essential characteristics of the low-temperature plasma nitriding of 316 austenitic stainless steels were precisely understood to extend the engineering treatise on the bulk nitrogen stainless steels for surface modification and treatment of stainless steels by nitriding. This plasma nitriding was applied to strengthen and harden the AISI316 wire surfaces toward its application on surgery wires.
- Published
- 2022
- Full Text
- View/download PDF
26. Femtosecond Laser Micro-/Nano-Texturing to Die Substrates for Fine Imprinting to Products
- Author
-
Tatsuhiko Aizawa, Tadahiko Inohara, Yohei Suzuki, and Tomomi Shiratori
- Abstract
A femtosecond laser micro−/nano-texturing was proposed to fabricate the coated and surface treated dies with the tailored textures for surface decoration and surface property control of metal, polymer and glass products. The polygonal model for microtextures with nanotextures by the LIPSS-effect was utilized to fabricate a DLC-coated SKD11 die with a star-shaped emblem. This die was set up into the cassette die set for directly imprinting this emblem into aluminum alloy and PET sheets. The periodic surface structure was synthesized as a surface geometry model to build up the super-hydrophobic surface on the nitrogen supersaturated AISI316 die. This die was also set up into a hot stamping system to directly imprint the hydrophobic surface onto the phosphorous glass products. Through the femtosecond laser micro−/nano-texturing and CNC-imprinting, the metal, polymer and glass product surfaces were optically decorated to have color grating and plasmonic brilliance and functionally controlled to be hydrophobic.
- Published
- 2022
27. Walking through Apertures in Individuals with Stroke.
- Author
-
Daisuke Muroi, Yasuhiro Hiroi, Teruaki Koshiba, Yohei Suzuki, Masahiro Kawaki, and Takahiro Higuchi
- Subjects
Medicine ,Science - Abstract
Walking through a narrow aperture requires unique postural configurations, i.e., body rotation in the yaw dimension. Stroke individuals may have difficulty performing the body rotations due to motor paralysis on one side of their body. The present study was therefore designed to investigate how successfully such individuals walk through apertures and how they perform body rotation behavior.Stroke fallers (n = 10), stroke non-fallers (n = 13), and healthy controls (n = 23) participated. In the main task, participants walked for 4 m and passed through apertures of various widths (0.9-1.3 times the participant's shoulder width). Accidental contact with the frame of an aperture and kinematic characteristics at the moment of aperture crossing were measured. Participants also performed a perceptual judgment task to measure the accuracy of their perceived aperture passability.Stroke fallers made frequent contacts on their paretic side; however, the contacts were not frequent when they penetrated apertures from their paretic side. Stroke fallers and non-fallers rotated their body with multiple steps, rather than a single step, to deal with their motor paralysis. Although the minimum passable width was greater for stroke fallers, the body rotation angle was comparable among groups. This suggests that frequent contact in stroke fallers was due to insufficient body rotation. The fact that there was no significant group difference in the perceived aperture passability suggested that contact occurred mainly due to locomotor factors rather than perceptual factors. Two possible explanations (availability of vision and/or attention) were provided as to why accidental contact on the paretic side did not occur frequently when stroke fallers penetrated the apertures from their paretic side.
- Published
- 2017
- Full Text
- View/download PDF
28. Feasibility of Mass Production Verified by Cut Surface Quality and Tool Load in Negative Clearance Blanking
- Author
-
Yohei Suzuki, Masao Murakawa, and Ming Yang
- Subjects
Quality (physics) ,Mechanics of Materials ,business.industry ,Mechanical Engineering ,Environmental science ,Production (economics) ,General Materials Science ,Process engineering ,business ,Blanking - Published
- 2021
- Full Text
- View/download PDF
29. Influence of Stainless Steel Grain Size on Adhesion of Microorganism
- Author
-
Ryosuke MIZUNO, Yohei SUZUKI, Yasuaki OSAWA, Takafumi KOMATSU, and Fumie YUSA
- Subjects
Mechanics of Materials ,Mechanical Engineering ,General Materials Science - Published
- 2021
- Full Text
- View/download PDF
30. Next-Generation Quality Control with the Latest Finnish Measuring Equipment
- Author
-
Yohei Suzuki
- Subjects
Mechanical Engineering ,Media Technology ,General Materials Science ,General Chemistry - Published
- 2021
- Full Text
- View/download PDF
31. Channel Estimation Scheme for a RAKE Receiver with Fractional Sampling in IEEE802.11b WLAN System.
- Author
-
Yu Imaoka, Hiroshi Obata, Yohei Suzuki, and Yukitoshi Sanada
- Published
- 2009
- Full Text
- View/download PDF
32. Aqueous column changes in the episcleral veins after the instillation of ripasudil versus latanoprost: A randomized, double-blind, crossover clinical trial
- Author
-
Marie, Suzuki, Yohei, Suzuki, Ryohei, Komori, Yusuke, Orii, Shogo, Arimura, Kentaro, Iwasaki, Yoshihiro, Takamura, and Masaru, Inatani
- Subjects
Hemoglobins ,Sulfonamides ,Cross-Over Studies ,Multidisciplinary ,Humans ,Latanoprost ,Prospective Studies ,Ophthalmic Solutions ,Isoquinolines - Abstract
Purpose: To investigate whether the topical administration of ripasudil ophthalmic solution enhances aqueous outflow in the episcleral vein of the human eye.Design: Two-sequence, prospective, randomized, double-blind, crossover trial.Participants: Sixteen eyes of 16 healthy participants were recruited in this study.Methods: Participants were randomized into one of the two crossover sequences to the instillation of ripasudil or the control drug, latanoprost, followed by a washout period of more than 2 days, and crossed over to the alternative instillation. The aqueous columns in the episcleral veins were recorded using a video capture system connected to a slit-light microscope (hemoglobin video imaging) before and 2 and 8 h after the instillation.Primary Outcome Measure: Comparisons between ripasudil and latanoprost for the changes of the aqueous column width after the instillation.Results: Two hours after the instillation, the ripasudil group had significantly greater dilation of the aqueous column width than the latanoprost group. Eight hours after the instillation, the ripasudil group had significantly greater dilation of the aqueous column width than the latanoprost group.Conclusions: Hemoglobin video imaging revealed the dilation of the aqueous column width in the episcleral veins of the human eye after the instillation of ripasudil ophthalmic solution.
- Published
- 2022
- Full Text
- View/download PDF
33. Multiple Types of Taste Disorders among Patients with COVID-19
- Author
-
Yuta Nanjo, Tomoko Okuma, Yumi Kuroda, Eri Hayakawa, Kohei Shibayama, Takashi Akimoto, Ryoko Murashima, Koichiro Kanamori, Takeo Tsutsumi, Yohei Suzuki, Yukiko Namba, Fumihiko Makino, Osamu Nagashima, Shinichi Sasaki, and Kazuhisa Takahashi
- Subjects
Taste Disorders ,SARS-CoV-2 ,Taste ,Internal Medicine ,COVID-19 ,Humans ,General Medicine ,Ageusia ,Dysgeusia ,Retrospective Studies - Abstract
Objective Based on the increasing incidence of smell and taste dysfunction among coronavirus disease 2019 (COVID-19) patients, such issues have been considered an early symptom of infection. However, few studies have investigated the type of taste components that are most frequently affected in COVID-19 patients. This study investigated the difference in frequencies of the types of taste component disorders among hospitalized COVID-19 patients. Methods In this retrospective, single-center, observational study, patients' background characteristics, clinical course, laboratory and radiological findings, and details on taste and/or smell disorders were collected and analyzed from medical records. Patients A total of 227 COVID-19 patients were enrolled, among whom 92 (40.5%) complained of taste disorders. Results Multiple types of taste disorders (hypogeusia/ageusia and hypersensitivity, or hypersensitivity and changing tastes) were reported in 10 patients. In particular, 23 patients reported hypersensitivity to at least 1 type of taste, and 2 patients complained of a bitter taste on consuming sweet foods. Impairment of all taste components was found in 48 patients (52.2%). The most frequent taste disorder was salty taste disorder (81 patients, 89.0%). Hypersensitivity to salty taste was most frequently observed (19 patients, 20.9%). Conclusion Patients with COVID-19 develop multiple types of taste disorders, among which salty taste disorder was the most frequent, with many patients developing hypersensitivity to salty taste. As smell and taste are subjective senses, further studies with the combined use of objective examinations will be required to confirm the findings.
- Published
- 2022
34. Exposure to the heated tobacco product IQOS generates apoptosis-mediated pulmonary emphysema in murine lungs
- Author
-
Naoko Arano Nitta, Tadashi Sato, Moegi Komura, Hitomi Yoshikawa, Yohei Suzuki, Aki Mitsui, Eriko Kuwasaki, Fumiyuki Takahashi, Yuzo Kodama, Kuniaki Seyama, and Kazuhisa Takahashi
- Subjects
Pulmonary and Respiratory Medicine ,Aerosols ,Male ,Mice ,Pulmonary Emphysema ,Physiology ,Physiology (medical) ,Tobacco ,Animals ,Apoptosis ,Cell Biology ,Tobacco Products ,Lung - Abstract
Pulmonary emphysema is predominantly caused by chronic exposure to cigarette smoke (CS). Novel tobacco substitutes, such as heated tobacco products (HTPs), have emerged as healthier alternatives to cigarettes. IQOS, the most popular HTP in Japan, is advertised as harmless compared with conventional cigarettes. Although some studies have reported its toxicity, few in vivo studies have been conducted. Here, 12-wk-old C57BL6/J male mice were divided into three groups and exposed to air (as control), IQOS aerosol, or CS for 6 mo. After exposure, the weight gain was significantly suppressed in the IQOS and CS groups compared with the control (−4.93 g; IQOS vs. air and −5.504 g; CS vs. air). The serum cotinine level was significantly higher in the IQOS group than in the control group. The neutrophils and lymphocyte count increased in the bronchoalveolar lavage fluid of the IQOS and CS groups compared with those in the control group. Chronic IQOS exposure induced pulmonary emphysema similar to that observed in the CS group. Furthermore, expression levels of the genes involved in the apoptosis-related pathways were significantly upregulated in the lungs of the IQOS-exposed mice. Cytochrome c, cleaved caspase-3, and cleaved poly (ADP-ribose) polymerase-1 were overexpressed in the IQOS group compared with the control. Single-stranded DNA and TdT-mediated dUTP nick-end labeling-positive alveolar septal cell count significantly increased in the IQOS group compared with the control. In conclusion, chronic exposure to IQOS aerosol induces pulmonary emphysema predominantly via apoptosis-related pathways. This suggests that HTPs are not completely safe tobacco products.
- Published
- 2022
35. Direct-Sequence/Spread-Spectrum Communication System with Sampling Rate Selection Diversity.
- Author
-
Yohei Suzuki, Anas Muhamad Bostamam, Mamiko Inamori, and Yukitoshi Sanada
- Published
- 2008
- Full Text
- View/download PDF
36. Structural and Bioelectrochemical Elucidation of Direct Electron Transfer-type Membrane-bound Fructose Dehydrogenase
- Author
-
Yohei Suzuki, Fumiaki Makino, Tomoko Miyata, Hideaki Tanaka, Keiichi Namba, Kenji Kano, Keisei Sowa, Yuki Kitazumi, and Osamu Shirai
- Abstract
Flavin adenine dinucleotide (FAD)-dependent fructose dehydrogenase (FDH) from Gluconobacter japonicus NBRC3260, a membrane-bound flavohemoprotein capable of direct electron transfer (DET)-type bioelectrocatalysis, was investigated from the viewpoints of structural biology and bioelectrochemistry. As FDH provides a strong DET-type catalytic signal, extensive research has been conducted. Structural analysis using cryo-electron microscopy (cryo-EM) and single-particle analysis revealed the entire FDH structure. The electron transfer (ET) pathway during the catalytic oxidation of D-fructose was investigated using thermodynamic and kinetic approaches in bioelectrochemistry, as well as structural information. Key amino acid residues that play important roles in substrate specificity and ET acceleration have also been proposed.
- Published
- 2022
- Full Text
- View/download PDF
37. Effects of N-linked glycans of bilirubin oxidase on direct electron transfer-type bioelectrocatalysis
- Author
-
Yohei Suzuki, Akira Itoh, Kunishige Kataoka, Satoshi Yamashita, Kenji Kano, Keisei Sowa, Yuki Kitazumi, and Osamu Shirai
- Subjects
Kinetics ,Oxidoreductases Acting on CH-CH Group Donors ,Polysaccharides ,Electrochemistry ,Biophysics ,DEET ,Electrons ,General Medicine ,Physical and Theoretical Chemistry ,Electrodes - Abstract
Bilirubin oxidase from Myrothecium verrucaria (mBOD) is a promising enzyme for catalyzing the four-electron reduction of dioxygen into water and realizes direct electron transfer (DET)-type bioelectrocatalysis. It has two N-linked glycans (N-glycans), and N472 and N482 are known as binding sites. Both binding sites located on opposite side of the type I (T1) Cu, which is the electrode-active site of BOD. We investigated the effect of N-glycans on DET-type bioelectrocatalysis by performing electrochemical measurements using electrodes with controlled surface charges. Two types of BODs with different N-glycans, mBOD and recombinant BOD overexpressed in Pichia pastoris (pBOD), and their deglycosylated forms (dg-mBOD and dg-pBOD) were used in this study. Kinetic analysis of the steady-state catalytic waves revealed that both size and composition of N-glycans affected the orientation of adsorbed BODs on the electrodes. Interestingly, the most favorable orientation was achieved with pBOD, which has the largest N-glycans. Furthermore, the effect of the orientation control by the N-glycans is cooperative with electrostatic interaction.
- Published
- 2022
38. Influence of Strain-Induced Martensitic Transformation of Austenitic Stainless Steel Sheet in Precision Blanking on Cut-Surface Quality
- Author
-
Tomomi Shiratori, Ming Yang, Masao Murakawa, and Yohei Suzuki
- Subjects
Surface (mathematics) ,Materials science ,Strain (chemistry) ,Mechanical Engineering ,Metallurgy ,engineering.material ,Condensed Matter Physics ,Quality (physics) ,Mechanics of Materials ,Diffusionless transformation ,engineering ,General Materials Science ,Austenitic stainless steel ,Blanking - Published
- 2020
- Full Text
- View/download PDF
39. Effects of Nanometric Control in Tool Cutting Edge Sharpness on Micropunching of Austenitic Stainless Steel SUS304
- Author
-
Ming Yang, Yohei Suzuki, Tomomi Shiratori, Takuya Aihara, Tomoaki Yoshino, and Shizuka Nakano
- Subjects
Materials science ,Mechanics of Materials ,Mechanical Engineering ,Metallurgy ,engineering ,General Materials Science ,Austenitic stainless steel ,engineering.material ,Edge (geometry) - Published
- 2020
- Full Text
- View/download PDF
40. The association between obesity and hyperactivity/anxiety among elementary school students in Japan
- Author
-
Naoko Sakamoto, Koutatsu Maruyama, Yohei Suzuki, Takeshi Tanigawa, Ai Ikeda, and Hiroo Wada
- Subjects
Male ,Pediatric Obesity ,Anxiety ,Childhood obesity ,03 medical and health sciences ,symbols.namesake ,0302 clinical medicine ,Japan ,Surveys and Questionnaires ,Prevalence ,medicine ,Humans ,030212 general & internal medicine ,Poisson regression ,Child ,Students ,Applied Psychology ,Schools ,030505 public health ,Body Weight ,Absolute risk reduction ,Strengths and Difficulties Questionnaire ,medicine.disease ,Obesity ,Health psychology ,Cross-Sectional Studies ,Relative risk ,symbols ,Female ,medicine.symptom ,0305 other medical science ,Psychology ,Clinical psychology - Abstract
We aimed to evaluate the association between hyperactivity/anxiety and obesity among elementary school students in Matsuyama City, Japan. We conducted a cross-sectional study of all 46 elementary school students (24, 296 students) in Matsuyama City. The questionnaire included question items from the Strengths and Difficulties Questionnaire (SDQ), as well as questions about height and weight. The students were classified into two groups according to Rohrer index. After separating the data by gender, we examined the association between (1) obesity and hyperactivity, (2) obesity and anxiety, and (3) obesity and combination of hyperactivity and anxiety, by estimating relative risk using Poisson regression model. We also conducted stratified analyses to examine the effect modification by age groups and unbalance of diet on those associations. Moreover, we calculated relative excess risk due to the interaction (RERI) to examine whether there was an additive interaction between hyperactivity and anxiety. Sixteen thousand forty-eight students were included in the present analysis. The prevalence ratio (PR) of being obese in girls who had both hyperactivity and anxiety was higher compared to girls without those symptoms (PR = 1.80; 95% CI 1.04–3.13). There was no significant difference in the prevalence ratio for obesity in boys, whether they were hyperactive, anxious, or neither. RERI was 0.00 for boys and 0.18 for girls. We found a significant association between obesity and co-existence of hyperactivity and anxiety among elementary school girls. Our findings strengthen the need to further explore the association between childhood obesity, hyperactivity, and anxiety.
- Published
- 2019
- Full Text
- View/download PDF
41. Application of Fluid Simulation in High-Speed Copper Sulfate Plating Using a Jet Flow Device
- Author
-
Hideo Honma, Yasushi Umeda, Christpher E. J. Cordonier, Osamu Takai, Joo-Hyong Noh, Toshinosuke Akutsu, and Yohei Suzuki
- Subjects
Fluid simulation ,Materials science ,Jet flow ,Plating ,General Engineering ,Copper sulfate ,Composite material - Published
- 2019
- Full Text
- View/download PDF
42. Research in Biocompatible Electroless Gold Plating
- Author
-
Hideo Honma, Junji Fukuda, Yohei Suzuki, Shoji Maruo, and Christopher E. J. Cordonier
- Subjects
Materials science ,Gold plating ,General Engineering ,Nanotechnology ,Biocompatible material - Published
- 2019
- Full Text
- View/download PDF
43. Exposure to the Heated Tobacco Product IQOS Generates Apoptosis-Mediated Pulmonary Emphysema in Mice Lungs
- Author
-
Kuniaki Seyama, Yuzo Kodama, Moegi Komura, Aki Mitsui, Fumiyuki Takahashi, Yohei Suzuki, Eriko Kuwasaki, Kazuhisa Takahashi, N. Nitta, Teruhiko Sato, and Hitomi Yoshikawa
- Subjects
Pathology ,medicine.medical_specialty ,Apoptosis ,business.industry ,Pulmonary emphysema ,medicine ,business ,Tobacco product - Published
- 2021
- Full Text
- View/download PDF
44. Femtosecond Laser Trimming with Simultaneous Nanostructuring to Fine Piercing Punch to Electrical Amorphous Steel Sheets
- Author
-
Tomomi Shiratori, Tomoaki Yoshino, Yohei Suzuki, Yoshihiro Kira, and Tatsuhiko Aizawa
- Subjects
Materials science ,nanostructure ,02 engineering and technology ,Chemical vapor deposition ,Edge (geometry) ,engineering.material ,Article ,chemistry.chemical_compound ,0203 mechanical engineering ,Tungsten carbide ,edge width ,TJ1-1570 ,electrical amorphous steel sheets ,Mechanical engineering and machinery ,Electrical and Electronic Engineering ,Composite material ,iron loss ,fine piercing ,Mechanical Engineering ,Diamond ,021001 nanoscience & nanotechnology ,induced damages by piercing ,diamond coated punch ,Amorphous solid ,edge profile ,020303 mechanical engineering & transports ,chemistry ,Control and Systems Engineering ,Femtosecond ,engineering ,0210 nano-technology ,Layer (electronics) ,Embossing - Abstract
A CVD (Chemical Vapor Deposition) diamond coated tungsten carbide (WC) and cobalt (Co) sintered alloy punch was trimmed by the femtosecond laser machining to sharpen its edge with about 2 μm and to simultaneously make nanostructuring to its side surface. In addition to the sharpened edge, its edge profile was formed to be homogeneous enough to reduce the damage layer width by piercing the electrical amorphous steel sheet stack. Each brittle sheet in the stacked work was damaged to have three kinds of defects by piercing, e.g., the droop-like cracking in the thickness and at the vicinity of hole, the wrinkling in peak-to-valley with partial cracking on the peaks, and the circumferential cracking. When using the WC (Co) punch with the inhomogeneous edge profile in the sharpened edge width, these three damages were induced into each sheet and the maximum damage width exceeded 80 μm. When using the punch with the sharpened edge and homogeneous edge profile, the wrinkling mode was saved and the total affected layer width was significantly reduced to less than 20 μm. Through the precise embossing experiments, this effect of punch edge profile condition to the induced damages was discussed with a statement on the nanostructuring effect on the reduction of damaged width in electrical amorphous steel sheets. The developed tool with the sharpened edge and homogenous edge condition contributes to the realization of a low iron loss motor with a reduced affected layer width.
- Published
- 2021
45. Laser Treatment CVD Diamond Coated Punch for Ultra-Fine Piercing of Metallic Sheets
- Author
-
Yohei Suzuki, Tatsuhiko Aizawa, Tomoaki Yoshino, Tadahiko Inonara, and Tomomi Shiratori
- Subjects
Materials science ,business.industry ,Laser treatment ,InformationSystems_INFORMATIONSTORAGEANDRETRIEVAL ,02 engineering and technology ,Chemical vapor deposition ,021001 nanoscience & nanotechnology ,Metal ,020303 mechanical engineering & transports ,0203 mechanical engineering ,visual_art ,visual_art.visual_art_medium ,Optoelectronics ,Ultra fine ,0210 nano-technology ,business ,GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries) - Abstract
CVD-diamond coated special tools have been widely utilized to prolong their tool life in practical production lines. WC (Co) punch for fine piercing of metallic sheets required for high wear-toughness to be free from chipping and damages and for high product quality to punch out the holes with sufficient dimensional accuracy. The laser trimming process was developed to reduce the surface roughness of diamond coating down to submicron level and to adjust its diamond layer dimensions with a sharp punch edge for accurate piercing. The pulsed laser irradiation was employed to demonstrate that micro-groove was accurately formed into the diamond coating. Less deterioration in the worked diamond film by this laser treatment was proved by the Raman spectroscopy. The femtosecond laser trimming was proposed to sharpen the punch edge down to 2 μm and to form the nano-textured punch side surfaces with the LIPSS (Laser Induced Periodic Surface Structuring)-period of 300 nm. Fine piercing experiments were performed to demonstrate that punch life was significantly extended to continuous punching in more than 10,000 shots and that mirror-shining hole surfaces were attained in every shot by regularly coining the nanotextures. The sharp punch edge with homogeneous edge profile was responsible for reduction of the induced damages into work sheet by piercing. The punch life was extended by the ejection mechanism of debris particles through the nanotextures on the punch side surface. The present laser treatment was useful in trimming and nanostructuring the complex-shaped punch edge for industrial application.
- Published
- 2021
46. Impaired psychomotor vigilance associated with sleep-disordered breathing in women working in the care of older adults in Japan
- Author
-
Narihisa, Miyachi, Ai, Ikeda, Ronald, Filomeno, Hiroo, Wada, Koutatsu, Maruyama, Yuka, Suzuki, Yohei, Suzuki, Satomi, Ikeda, Yumi, Hashimoto, Yasunari, Koyama, and Takeshi, Tanigawa
- Subjects
Adult ,Adolescent ,Middle Aged ,Occupational Diseases ,Young Adult ,Cross-Sectional Studies ,Sleep Apnea Syndromes ,Caregivers ,Japan ,Humans ,Female ,Wakefulness ,Psychomotor Performance ,Aged - Abstract
With a rapidly aging society, there is increasing interest in the health of female workers in the field of care services for older adults due to increasing demands to maintain 24-h care and to support older adults without errors or accidents. Therefore, the purpose of this cross-sectional study was to examine the association between sleep-disordered breathing (SDB) and sustained attention in women caring for older adults in Japan.The study was conducted in women aged 18-67 years old working in care service facilities for older adults in Japan. The sustained attention of participants was measured by the 10-min psychomotor vigilance task (PVT). SDB was assessed based on the respiratory disturbance index (RDI), which was measured using an ambulatory airflow monitor with a polyvinylidene fluoride (PVDF) film sensor to monitor the respiratory airflow of nasal and oral breathing. The participants wore the monitor to record the breathing status while asleep at home. The severity of SDB was categorized as follows: normal, RDI 5 events/h; mild SDB, RDI 5-10 events/h; and moderate-to-severe SDB, RDI ≥ 10 events/h.Of 688 women enrolled, medians of age, body mass index (BMI), sleep duration, and prevalence of hypertension tended to be higher with increasing RDI. No significant association was found between RDI and PVT parameters. However, when we limited the analysis to women with BMI ≥ 22 kg/mOur findings suggest that SDB is associated with reduced sustained attention in participants with BMI ≥ 22 kg/m
- Published
- 2020
47. Prognostic Impact of No-Flow Time on 30-Day Neurological Outcomes in Patients With Out-of-Hospital Cardiac Arrest Who Received Extracorporeal Cardiopulmonary Resuscitation
- Author
-
Kazufumi Tsuchihashi, Nobuaki Kokubu, Junichi Nishida, Naoto Murakami, Jun Nakata, Nobutaka Nagano, Tetsuji Miura, Ryo Nishikawa, Eichi Narimatsu, and Yohei Suzuki
- Subjects
Adult ,Male ,Time Factors ,medicine.medical_treatment ,Pupil diameter ,030204 cardiovascular system & hematology ,No flow time ,Extracorporeal ,Out of hospital cardiac arrest ,Time-to-Treatment ,03 medical and health sciences ,Disability Evaluation ,0302 clinical medicine ,Extracorporeal Membrane Oxygenation ,medicine ,Humans ,Extracorporeal cardiopulmonary resuscitation ,In patient ,Cardiopulmonary resuscitation ,Aged ,Retrospective Studies ,Neurologic Examination ,business.industry ,Extracorporeal circulation ,030208 emergency & critical care medicine ,General Medicine ,Recovery of Function ,Middle Aged ,Cardiopulmonary Resuscitation ,Treatment Outcome ,Anesthesia ,Female ,Cardiology and Cardiovascular Medicine ,business ,Out-of-Hospital Cardiac Arrest - Abstract
BACKGROUND How the time sequence of cardiopulmonary resuscitation (CPR) procedures is related to clinical outcomes in patients with out-of-hospital cardiac arrest (OHCA) remains unclear. This study examined the impact of the time interval from collapse to start of CPR (no-flow time, NF time) and the time interval from start of CPR to implementation of extracorporeal CPR (ECPR) (low-flow time, LF time) on neurological outcomes.Methods and Results:During the period from 2010 to 2015, we enrolled 85 patients who received ECPR. Fourteen patients (16.5%) showed favorable 30-day neurological recovery. NF time was shorter in the favorable neurological recovery group than in the unfavorable recovery group (1.4±3.0 vs. 5.2±5.8 min, P
- Published
- 2020
48. Comparison of Carbon Dynamics among Three Cool-Temperate Forests (Quercus serrata, Larix kaempferi and Pinus densiflora) under the Same Climate Conditions in Japan
- Author
-
Yuki Kato, H. Koizumi, Yoshiaki Sakamaki, Mitsutoshi Tomotsune, Nobuhiko Suminokura, Yohei Suzuki, Rina Masuda, and Yuta Koyama
- Subjects
Biomass (ecology) ,010504 meteorology & atmospheric sciences ,biology ,Primary production ,Forestry ,010501 environmental sciences ,biology.organism_classification ,Quercus serrata ,01 natural sciences ,Pinus densiflora ,Larix kaempferi ,Forest ecology ,Litter ,Environmental science ,Temperate rainforest ,0105 earth and related environmental sciences - Abstract
To understand the role of forest ecosystems in the global carbon cycle, it is important to clarify the factors affecting the carbon balance of forest ecosystems. However, little is known about the direct effect of forest types, especially dominant species, on their different carbon dynamics. To clarify the effect of difference in forest types, an experiment was conducted in three forests, which were located in the same place and exposed to the same climate conditions. These forests were middle-aged (40 - 45 years) and dominated by Quercus serrata (Q forest), Larix kaempferi (L forest) and Pinus densiflora (P forest). Net primary production (NPP), heterotrophic respiration (HR) and net ecosystem production (NEP) were estimated in each forest, using a biometric method over one year. For NPP estimated from the annual growth of tree biomass (ΔB) and amount of litter (LF), P forest NPP (5.3 MgC·ha-1·yr-1) was higher than Q and L forest NPP (4.6 and 3.2 MgC·ha-1·yr-1). The difference was affected by a significant difference in ΔB (p = 0.032) and LF (p -1·yr-1) was higher than L and P forest (2.3 and 2.1 MgC·ha-1·yr-1). This difference could result from the amount of litter (respiration substrate) and chemical properties of litter (lability of decomposition). The NEP, which was calculated from the difference between NPP and HR, varied widely among the forest types (0.5, 0.9 and 3.2 MgC·ha-1·yr-1 in Q, L and P forests, respectively). The range of values among the forest types was comparable to those among age sequences and climate zones in previous studies. These results suggest that the difference in forest types (especially dominant species) can potentially lead to a large variation in carbon dynamics, in ecosystems located in the same place.
- Published
- 2019
- Full Text
- View/download PDF
49. Effects of Ion Processing of Cutting Edge of Tools on Tool Wear and Punching Characteristics in Micropunching Process
- Author
-
Yohei Suzuki, Tomomi Shiratori, Tomoaki Yoshino, Ming Yang, and Shizuka Nakano
- Subjects
Materials science ,Mechanics of Materials ,Mechanical Engineering ,Process (computing) ,Mechanical engineering ,General Materials Science ,Edge (geometry) ,Tool wear ,Punching ,Ion - Published
- 2019
- Full Text
- View/download PDF
50. Processing of Metal Microgear Tooth Profile by Finish Blanking and Extrusion Blanking and Evaluation of Cut-surface Shape
- Author
-
Yohei Suzuki, Ming Yang, Tomomi Shiratori, and Masao Murakawa
- Subjects
Materials science ,Mechanics of Materials ,Mechanical Engineering ,General Materials Science ,Extrusion ,Composite material ,Surface shape ,Blanking - Published
- 2019
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.