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81.
Fluorescent imaging of endothelial glycocalyx layer with wheat germ agglutinin using intravital microscopy 下载免费PDF全文
Hanae Kataoka Akira Ushiyama Hayato Kawakami Yoshihiro Akimoto Sachie Matsubara Takehiko Iijima 《Microscopy research and technique》2016,79(1):31-37
Endothelial glycocalyx (GCX) is located on the apical surface of vascular endothelial cells and is composed of a negatively‐charged network of proteoglycans and glycoproteins. The GCX plays an important role in maintaining the integrity of vascular walls and preventing leakage of plasma. Therefore, degradation of the GCX is believed to lead to pathological leakage of plasma. Because the GCX is a very thin layer, its ultrastructural image has been demonstrated on electron microscope. To explore the function of the GCX, it should be visualized by a microscope in vivo. Thus, we developed in vivo visualization technique of the GCX under fluorescence microscopy using a mouse dorsal skinfold chamber (DSC) model. To label and visualize the GCX, we used fluorescein isothiocyanate (FITC)‐labeled lectin, which has a high specificity for sugar moieties. We examined the affinity of the different lectins to epivascular regions under an intravital fluorescent microscope. Among seven different lectins we examined, FITC labeled Triticum vulgaris (wheat germ) agglutinin (WGA) delineated the GCX most clearly. Binding of WGA to the GCX was inhibited by chitin hydrolysate, which contained WGA‐binding polysaccharide chains. Furthermore, the septic condition attenuated this structure, suggesting structural degradation of endothelial GCX layer. In conclusion, FITC‐labeled WGA lectin enabled visualization of endothelial GCX under in vivo fluorescence microscopy. Microsc. Res. Tech. 79:31–37, 2016. © 2015 Wiley Periodicals, Inc. 相似文献
82.
An approach to mobile software robots for the WWW 总被引:1,自引:0,他引:1
Kato K. Someya Y. Matsubara K. Toumura K. Abe H. 《Knowledge and Data Engineering, IEEE Transactions on》1999,11(4):526-548
This paper describes a framework for developing mobile software robots by using the PLANET mobile object system, which is characterized by a language-neutral layered architecture, the native code execution of mobile objects, and asynchronous object passing. We propose an approach to implementing mobile Web search robots that takes full advantage of these characteristics, and we base our discussion of its effectiveness on experiments conducted in the Internet environment. The results show that the PLANET approach to mobile Web search robots significantly reduces the amount of data transferred via the Internet and that it enables the robots to work more efficiently than the robots in the conventional stationary scheme whenever nontrivial amounts of HTML files are processed 相似文献
83.
Kiyofumi Takabatake Masakazu Matsubara Eiki Yamachika Yuki Fujita Yuki Arimura Kazuki Nakatsuji Keisuke Nakano Histoshi Nagatsuka Seiji Iida 《International journal of molecular sciences》2021,22(22)
Background: We investigated and compared the osteogenic potential and bone regeneration capacities of dedifferentiated fat cells (DFAT cells) and adipose-derived stem cells (ASCs). Method: We isolated DFAT cells and ASCs from GFP mice. DFAT cells were established by a new culture method using a mesh culture instead of a ceiling culture. The isolated DFAT cells and ASCs were incubated in osteogenic medium, then alizarin red staining, alkaline phosphatase (ALP) assays, and RT-PCR (for RUNX2, osteopontin, DLX5, osterix, and osteocalcin) were performed to evaluate the osteoblastic differentiation ability of both cell types in vitro. In vivo, the DFAT cells and ASCs were incubated in osteogenic medium for four weeks and seeded on collagen composite scaffolds, then implanted subcutaneously into the backs of mice. We then performed hematoxylin and eosin staining and immunostaining for GFP and osteocalcin. Results: The alizarin red-stained areas in DFAT cells showed weak calcification ability at two weeks, but high calcification ability at three weeks, similar to ASCs. The ALP levels of ASCs increased earlier than in DFAT cells and showed a significant difference (p < 0.05) at 6 and 9 days. The ALP levels of DFATs were higher than those of ASCs after 12 days. The expression levels of osteoblast marker genes (osterix and osteocalcin) of DFAT cells and ASCs were higher after osteogenic differentiation culture. Conclusion: DFAT cells are easily isolated from a small amount of adipose tissue and are readily expanded with high purity; thus, DFAT cells are applicable to many tissue-engineering strategies and cell-based therapies. 相似文献
84.
M. Jeong M. Song T. Ueno T. Mizusaki A. Matsubara S. Lee 《Journal of Low Temperature Physics》2010,158(3-4):659-665
We report NMR measurements of transverse relaxation rate 1/T 2 of the 31P nuclear spins in metallic Si:P (concentration of dopant P, n=18×1018 and 56×1018 cm?3) at temperatures between 45 mK and 5 K in a magnetic field of 7 T. Above 1.4 K, 1/T 2 is constant independent of temperature as well as concentration and is determined by magnetic dipolar interaction between the 31P and 29Si nuclear spins. As temperature decreases below 1.4 K, 1/T 2 increases over the dipolar-determined value by an order of magnitude and levels off around 0.6 K. The concentration dependence of 1/T 2 at low temperatures suggests that 1/T 2 below 1.4 K is determined by the coupling between the 31P nuclear spins. We understand 1/T 2 at low temperatures originates from the RKKY interaction. We explain the temperature dependence of 1/T 2 between 0.6 K and 1.4 K by the motional-narrowing expression of 1/T 2 with a temperature-dependent correlation time of the fluctuating local field due to the RKKY interaction. 相似文献
85.
Yasushi Abe Kunio Matsubara Kiyoaki Sasagawa Kouki Matsuse 《IEEJ Transactions on Electrical and Electronic Engineering》2008,3(1):113-119
This paper presents a medium‐voltage inverter applying series connected general‐purpose 1.2 kV insulated gate bipolar transistors (IGBTs) as a switching device to achieve low switching losses compared to inverters applying high‐voltage IGBTs with over 3 kV rating. Gate signal synchronization, which is essential to keep the balance of collector‐emitter voltages across the IGBTs, is achieved by magnetically coupling all gate lines using a simple two‐windings transformer. In order to obtain better voltage balancing, influence of stray capacitance distribution associated with an insulating substrate in a two‐in‐one IGBT module on the voltage sharing is investigated, and an optimized layout of heat sinks for the IGBT modules is proposed. To validate some performances concerning the device losses and the voltage sharing, a 170 kVA inverter based on three 1.2 kV IGBTs connected in series is built and evaluated. The experimental results are shown. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
86.
J. Saida T. Osuna M. Ohnuma E. Matsubara A. Inoue 《Science and Technology of Advanced Materials》2013,14(4):311-318
The structure and primary devitrification process of the melt-spun Cu60(Zr or Hf)30Ti10 alloys were investigated. It was confirmed that the compositional segregation in the diameter range of 5–10 nm exists in the as-quenched state. The nanocrystalline particles with cubic structure are observed in the glassy matrix in thehigh-resolution transmission electron microscopy images, of which size is corresponding to the scale of compositional segregation. Small-angle X-ray scattering measurement also indicates the development of nanoscale inhomogeneity with the same size as that of nanocrystalline particles. The nanocrystalline region has high Cu content. In contrast, Zr or Hf and Ti elements are enriched in the glassy region. These results are recognized as the formation of novel structure consisting of the glassy and nanocrystalline phases. It is suggested that the precipitation of bcc CuZr phase as a primary crystallization phase proceeds in the glassy phase remaining the nanocrystalline phase in the Cu–Zr–Ti alloy. Meanwhile, the glassy and nanocrystalline phases are transformed to an orthorhombic Cu8Hf3 phase at the initial crystallization stage in the Cu–Hf–Ti alloy. These differences of crystallization process are consistent with the results of thermodynamic and kinetic analyses of the transformation mode. 相似文献
87.
Koji Matsubara Takahiro Miura Atsushi Sakurai Kenya Yamazaki Makoto Takeda 《Numerical Heat Transfer, Part A: Applications》2013,63(3):234-253
Direct numerical simulation was performed for the spatially advancing turbulent flow and heat transfer in a two-dimensional curved channel equating the radius ratio to 0.92 or 0.8. The frictional Reynolds number was fixed at 150, whereas the Prandtl number was set at 0.71. According to the numerical result, the remarkable enhancement of heat transfer occurred on the outer wall, suggesting the organized vortex activated the heat transfer. The budgets of Reynolds stresses clarified that the onset and growth of the organized flow was assisted by the direct energy transfer from the mean flow. 相似文献
88.
Atsushi Sakurai Shigenao Maruyama Koji Matsubara 《Numerical Heat Transfer, Part A: Applications》2013,63(8):625-640
The purpose of this study is to develop the radiation element method by ray emission method (REM2) code appropriate for coupling with the bioheat transfer equation, and to clarify the photothermal effect of various parameters inside biological tissues. First, the REM2, which involves the air-tissue interface effect, is validated with the existing literature. In order to clarify the effects of optical and thermophysical properties of biological tissues, a one-dimensional tissue model of CW light transport and bioheat transfer is employed. The present study provides nondimensional results, which are obtained by varying refractive index, extinction coefficient, scattering albedo, blood perfusion parameter, and conduction-radiation parameter, show valuable guidance for understanding the coupled light and bioheat transport in tissues. 相似文献
89.
M. Shibata T. Arai A. Fukuda H. Funahashi T. Haseyama S. Ikeda K. Imai Y. Isozumi T. Kato Y. Kido A. Matsubara S. Matsuki T. Mizusaki R. Nakanishi T. Nishimura D. Ohsawa A. Sawada Y. Takahashi M. Tosaki S. Yamada K. Yamamoto 《Journal of Low Temperature Physics》2008,151(3-4):1043-1048
A microwave single-photon detector was developed with highly-excited alkaline Rydberg-atoms in a cooled resonant cavity to
search for dark matter axions. This detector belongs to a microwave single-photon counter, thus being free from the standard
quantum limit (SQL). High sensitivity of the present detector system was demonstrated by measuring the thermal blackbody radiations
in the cavity at temperatures as low as 70 mK where the sensitivity is below the SQL.
The detection sensitivity of the present system is mainly limited by stray electric fields present in the detection region.
Practical design of a new experimental scheme with a guiding electric field through the atomic-beam trajectory is here presented
and discussed to avoid the effect of stray electric field and thus to improve the detection sensitivity.
相似文献
90.
Koya Arai Masanori Matsubara Yukie Sawada Tatsuya Sakamoto Tohru Kineri Yasuo Kogo Tsutomu Iida Keishi Nishio 《Journal of Electronic Materials》2012,41(6):1771-1777
A single ??-structure thermoelectric (TE) module based on p-type NaCo2O4, n-type Mg2Si, and Ni electrode was fabricated by the spark plasma sintering (SPS) method. The NaCo2O4 powder was synthesized by using a metal?Ccitric acid complex decomposition method. Bulk Mg2Si prepared by melt quenching was ground into a powder and sieved to particle size of 75???m or less. To obtain a sintered body of NaCo2O4 or Mg2Si, the powder was sintered using SPS. Pressed Ni powder or mixed powder consisting of Ni and SrRuO3 powder was inserted between these materials and the Ni electrode in order to connect them, and electrical power was passed through the electrodes from the SPS equipment. The open-circuit voltage (V OC) values of a single module in which TE materials were connected to the Ni electrodes by using pressed Ni powder was 82.7?mV, and the maximum output current (I max) and maximum output power (P max) were 212.4?mA and 6.65?mW at ??T?=?470?K, respectively. On the other hand, V OC of a single module in which TE materials and an Ni electrode were connected with a mixed powder (Ni:SrRuO3?=?6:4 volume fraction) was 109?mV, and I max and P max were 4034?mA and 109?mW at ??T?=?500?K, respectively. These results indicate that the resistance at the interface between the TE materials and the Ni electrode can be decreased and the output power can be increased by application of a buffer layer consisting of Ni and SrRuO3. 相似文献