检索结果-南通市图书馆

On-chip 3D rotation of oocyte based on a vibration-induced local whirling flow

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Microsystems & Nanoengineering 2015年第1期1卷 150-158页

作者： Takeshi Hayakawa Shinya sakuma Fumihito Arai Department of Micro-Nano Systems Engineering Nagoya UniversityNagoya-CityAichi-Pref.JAPAN

We propose a novel on-chip 3D cell rotation method based on a vibration-induced *** circular vibration is applied to a microchip with micropillar patterns,a highly localized whirling flow is induced around the *** direction and velocity of this flow can be controlled by changing the direction and amplitude of the applied ***,this flow can be induced on an open chip *** this study,we adopted a microchip with three micropillars arranged in a triangular configuration and an xyz piezoelectric actuator to apply the circular *** the centre of the micropillars,the interference of the vibration-induced flows originating from the individual micropillars induces rotational ***,a biological cell placed at this centre rotates under the influence of the *** three-plane circular vibrations in the xy,xz or yz plane,the cell can rotate in both the focal and vertical planes of the *** this 3D cell rotation method,we measured the rotational speeds of mouse oocytes in the focal and vertical planes as 63.7±4.0°s^(−1) and 3.5±2.1°s^(−1),***,we demonstrated the transportation and rotation of the mouse oocytes and re-positioned their nuclei into a position observable by microscope.

关键词： lab on a chip cell manipulation vibration-induced flow acoustic streaming

Role of atomic-scale thermal fluctuations in the coercivity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2020年第1期6卷 1084-1090页

作者： Yuta Toga Seiji Miyashita Akimasa sakuma Takashi Miyake National Institute for Materials Science(NIMS) Tsukuba 305-0047Japan Elements Strategy Initiative Center for Magnetic Materials(ESICMM) TsukubaJapan Institute for Solid State Physics University of TokyoKashiwa 277-8581Japan The Physical Society of Japan Tokyo 113-0033Japan Department of Applied Physics Tohoku UniversitySendai 980-8579Japan National Institute of Advanced Industrial Science and Technology(AIST) Tsukuba 305-8568Japan

The microscopic mechanism of coercivity at finite temperature is a crucial issue for permanent *** we present the temperature dependence of the coercivity of an atomistic spin model for the highest-performance magnet Nd_(2)Fe_(14)*** quantitative analysis of the magnetization reversal with thermal fluctuations,we focus on the free energy landscape as a function of the *** free energy is calculated by the replica-exchange Wang–Landau *** approach allows us to address a slow nucleation problem,i.e.,thermal activation effects,in the magnetization *** concretely observed that the thermal fluctuations lead to a downward convexity in the coercivity concerning the ***,through analyzing the microscopic process of the thermal activation(nucleation),we discover the activation volume is insensitive to a magnetic field around the *** insensitivity explains the linear reduction of the free energy barrier by the magnetic field in the nucleation process.

关键词： thermal activation magnetization

Optimal Total Sleep Duration per Day to Maintain Health-Related Quality of Life in Male Collegiate Athletes:A Cross-Sectional Study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Science in Sport and Exercise 2023年第4期5卷 360-368页

作者： Yuko Morita Taeko Sasai-sakuma Institute of Arts and Sciences Tokyo University of Science6-3-1NiijukuKatsushika-kuTokyo 125-8585Japan Department of Clinical Laboratory Science Faculty of Medical TechnologyTeikyo University2-11-1KagaItabashi-kuTokyo 173-8605Japan

Purpose This study investigated the optimal total sleep duration per day required by collegiate athletes to maintain the physical and mental health-related quality of life(HRQOL),compared with non-athlete *** In this cross-sectional study,a questionnaire survey was conducted to assess demographic variables,lifestyle and sleep habits,and HRQOL in 392 collegiate students(non-athletes,n=174;athletes,n=218).Physical component summary(PCS)and mental component summary(MCS)were assessed using the short-form-8 health *** with both good PCS and MCS were defined as having a good *** confirm an association between the total sleep duration per day and good HRQOL,logistic regression analyses were conducted in non-athlete students and collegiate athletes ***,receiver-operating curve(ROC)analyses were performed for the detection of the cut-off point of total sleep duration per day sufficient to maintain a good *** The average total sleep duration per day was 7 h 19 min for collegiate athletes,and 78.9%of them had a worse *** cut-off point of total sleep duration per day to maintain good HRQOL for collegiate athletes was 7.92 h(area under ROC,0.64;P=0.038;sensitivity,75.4%;specificity,57.9%),which was longer than 6.79 h for non-athlete *** Collegiate athletes required longer nocturnal sleep than non-athlete ***,their habitual nocturnal sleep duration was shorter compared to their optimal duration;around 70%of them faced chronic insufficient *** sleep habits and sleep education is important in maintaining their good health-related quality of life.

关键词： Athlete Sleep duration Health-related quality of life Insufficient sleep

Exploitation of shape memory alloy actuator using resistance feedback control and its development

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2010年第1期20卷 97-103页

作者： Hiroki CHO Takaei YAMAMOTO Yuji TAKEDA Akihiko SUZUKI Toshio sakuma Faculty of Engineering Oita University700 DannoharuOita 870-1192Japan TAKE R&D 2-7-27UmedaKasukabeJapan

The relationship between phase transformation and electric resistivity of Ti-42.6Ni-7Cu SMA was *** the isothermal tensile tests,stress-strain curve shows large hysteresis and nonlinearity,whereas the resistivity-strain curve can be fitted by *** resistivity of SMAs can be determined from the volume fractions of the martensitic and austenitic *** characteristics leads to that the resistance of the SMAs is used as a parameter of strain of SMAs.A SMA actuator using resistance feedback control system was proposed,which can control and retain positioning at any positions without using sensor devices,and the deviation of position of this system was less than 3 μm.

关键词： Ti-Ni-Cu alloy shape memory alloy resistivity shape memory characteristics phase transformation

Dietary Control of Lactase Expression in the Weaning Rat

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 1996年第2期9卷 181-184页

作者： K．sakuma Y．WATANBE 等 DepartmentofMolecularNutrition KagawaNutritionUriversitySakadoSaitama350－02Japan DepartmentofMolec

The decline in lactase activity during weaning has been well established. However, its molecuIar mechanism remains to be explored. We studied changes in the expression of lactase in terms of the transcription and translation processes in rat microvillus membrane by Northern blot and Western blot analysis, respectively. To examine the effect of dietary change from a milk to a non-milk diet on the developmental pattern of lactase expression, weaning was prevented by keeping the rats under suckling conditions for 27 days after birth. This treatment only suppressed the extent of decline: while the weanlings showed 17 percent activity compared to that of 4-day-old rats, the prolonged suckling rats showed only 42 percent. The changes in the expression of lactase mRNA and protein were parallel with the change of lactase activity. In other words, the fundamental pattern of significant depression of lactase expression occurred relatively independent of dietary *** observation indicates that the regulation of lactase expression is firmly determined at the transcriptional level, and that dietary factor such as the termination of lactose ingestion has only a relatively minor effect

关键词： Dietary Control of Lactase Expression in the Weaning Rat

Design of Electrohydrodynamic Devices with Consideration of Electrostatic Energy

在线全文

学校读者我要写书评

暂无评论

Cyborg and Bionic Systems 2021年第1期2021卷 32-39页

作者： Tasuku Sato Shinya sakuma Masato Hijikuro Shingo Maeda Masayuki Anyoji Yoko Yamanishi Kyushu University 744 MotookaNishi-kuFukuoka 819-0395Japan Kyushu University 6-1 Kasuga KoenKasuga-shiFukuoka 816-8580Japan Shibaura Institute of Technology 3-7-5 ToyosuKoto-kuTokyo 135-8548Japan

The importance of actuators that can be integrated with flexible robot structures and mechanisms has increased in recent years with the advance of soft *** particular,electrohydrodynamic(EHD)actuators,which have expandable integrability to adapt to the flexible motion of soft robots,have received much attention in the field of soft *** have deepened the understanding of steady states of EHD phenomena but nonsteady states are not well *** herein observe the development process of fluid in a microchannel adopting a Schlieren technique with the aid of a high-speed *** addition,we analyze the behavior of fluid flow in a microchannel that is designed to have pairs of parallel plate electrodes adopting a computational fluid dynamics *** indicate the importance of considering flow generated by electrostatic energy,which tends to be ignored in constructing and evaluating EHD devices,and by the body force generated by the ion-drag *** considering these effects,we estimate the development process of EHD flow and confirm the importance of considering the generation of vortices and their interactions inside the microchannel during the development of EHD devices.

关键词： EHD flow electrostatic

Microstructural evolution in Al-Zn eutectoid alloy by hot-rolling

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2014年第7期24卷 2107-2111页

作者： Toshiaki MANAKA Goroh ITOH Yoshinobu MOTOHASHI Takaaki sakuma School of Science and Engineering Ibaraki University College of Engineering Ibaraki University

The Al-Zn eutectoid alloy has been widely known as a typical superplastic metallic material, where fine-grained microstructure is usually obtained by heat treatment. Recently, thermo-mechanical controlled process has also been reported to provide a fine-grained microstructure. In the present study, Al-Zn alloy ingots of 20 mm in thickness were homogenized and hot-rolled to a thickness of 2 mm under three processes： 1） the specimen was air-cooled after homogenization and hot-rolled; 2） the specimen was water-quenched after homogenization and hot-rolled; 3） the specimen was immediately hot-rolled after homogenization. Microstructural observation showed that, in processes l and 3, lamellar microstructure was formed after homogenization, and became fragmented to fine-grained microstructure as the hot roiling process proceeded. In process 2, fine-grained microstructure without lamellar microstructure was attained throughout the hot-rolling process. A minimum grain size of 1.6 μm was obtained in process 3. Tensile tests at room temperature showed that the elongation to failure was the largest in process 3.

关键词： aluminum-zinc alloy eutectoid microstructure control hot-rolling superplastic material

Role of the STRIPAK complex and the Hippo pathway in synaptic terminal formation

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2017年第4期12卷 578-579页

作者： Chisako sakuma Takahiro Chihara Department of Tropical Medicine Center for Medical EntomologyThe Jikei University School of Medicine Department of Biological Science Graduate School of ScienceHiroshima University

To transmit neural information from pre to postsynaptic neu- rons, the number, morphology, and function of the synapse have to be strictly regulated. Failures in synaptic formations are linked to neural disorders. For example, it is suggested that localization of N-methyl-D-aspartate （NMDA） receptors plays important roles in NMDA receptor-induced excitotoxicity, which is in turn thought to contribute to cell death associated with certain neurodegenerative diseases （Parsons and Ray-mond, 2014）. Furthermore, synaptic overgrowth is observed in Drosophila dfmrl （homolog of mammalian FMRI） gene mu- tant, which causes the Fragile X syndrome （Zhang et al., 2001）.

关键词： Hippo synaptic formations transmit localization NMDA aspartate homolog excitatory dynamically

Ion Beam Surface Modification of Y-TZP and Effects of Subsequent Annealing

在线全文

学校读者我要写书评

暂无评论

材料热处理学报 2004年第05B期25卷 1032-1036页

作者： Y.Motohashi T.Shibata S.Harjo T.sakuma M.Ishihara S.Baba K.Sawa Research Center for Superplasticity Ibaraki University Nakanarusawa 4-12-1 Hitachi Ibaraki 316-8511 Japan Oarai Research Establishment JAERI Oarai Higashiibaraki-gun Ibaraki 311-1394 Japan

Tetragonal zirconia polycrystals containing 3 mol% yttria (3Y-TZP), which show Superplasticity at high temperatures, were irradiated using 130 MeV Zr+" ions in the TANDEM accelerator facility at Tokai Research Establishment, JAERI. The irradiation induced atomic displacement damage was analyzed by TRIM code. Changes in the mechanical properties and fracture behavior caused by the ion irradiation and the effects of subsequent annealing were studied. The distribution of micro-indentation depth as a function of the indentation position from the irradiated surface to the specimen interior was also examined. The occurrence of compressive residual stresses and increases in hardness and fracture toughness were found in the as-irradiated surface region of the specimen. The subsequent annealing revealed that these quantities were decreased gradually with raising the annealing temperature. Probable causes of the generation of the residual stress and the changes in mechanical properties and fracture mode due to the irradiation are discussed.

关键词： ion beam surface modification annealing 3Y-TZP residual stress mechanical properties micro-indentation Superplasticity