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21.
Mikiyasu Shirai Matthew Beard James T. Pearson Takashi Sonobe Hirotsugu Tsuchimochi Yutaka Fujii Emily Gray Keiji Umetani Daryl O. Schwenke 《Journal of synchrotron radiation》2013,20(3):441-448
Synchrotron radiation microangiography is a powerful tool for assessing adverse changes in pulmonary vessel density associated with primary pulmonary hypertension (PH). Congestive heart failure (CHF) leads to a `secondary' onset of PH, yet it is unknown whether secondary PH is also associated with reduced vessel density. This study utilized synchrotron radiation to assess both pulmonary vessel density and endothelial function in a Dahl rat model of CHF with secondary PH. High salt‐fed Dahl salt‐sensitive (Dahl‐S) and salt‐resistant (Dahl‐R) rats were anesthetized and microangiography was performed to assess the pulmonary vessel density and vascular responses to (i) sodium nitroprusside (5.0 µg kg?1 min?1), (ii) acetylcholine (3.0 µg kg?1 min?1) and (iii) ET‐1A receptor blockade, BQ‐123 (1 mg kg?1). Dahl‐S rats developed CHF and secondary PH as evident by endothelial dysfunction, impaired vasodilatory responses to acetylcholine, enhanced vasodilatory responses to BQ‐123 and extensive pulmonary vascular remodeling. Consequently, the pulmonary vessel density was adversely reduced. Interestingly, the etiology of secondary PH manifests with structural and functional changes that are comparable with that previously reported for primary PH. One important discrepancy, however, is that ET‐1 modulation of pulmonary vessels is most striking in vessels with a diameter range of 100–200 µm in secondary PH, in contrast to a range of 200–300 µm in primary PH. Such discrepancies should be considered in future studies investigating primary and secondary forms of PH. 相似文献
22.
Tago Teruoki Tashiro Shizuka Hashimoto Yukiko Wakabayashi Katsuhiko Kishida Masahiro 《Journal of nanoparticle research》2003,5(1-2):55-60
Silica (SiO2)-coated ceria (CeO2) nanoparticles were prepared using water-in-oil microemulsion. Polyoxyethylene (15) cetylether and cyclohexane were used as a surfactant and organic solvent. SiO2-coated CeO2 nanoparticles were obtained by hydrolysis of metal alkoxide (tetraethylorthosilicate, TEOS) in the solution containing CeO2 precursor nanoparticles. The effects of CeO2 sources (Ce metal salt) and CeO2 particle-forming agents on the morphology of SiO2–CeO2 particles were investigated. Observation via transmission electron microscopy revealed that the type of particle-forming agent affected the nanoparticles' morphology and that CeO2 nanoparticles were spherically coated with SiO2 when using oxalic acid ((COOH)2) as a particle-forming agent of CeO2. Furthermore, the transmittance of the particles was high in the visible region (above 400 nm) and decreased in the ultraviolet region. 相似文献
23.
The monotone asymmetric travelling salesman polytope P?nT is defined to be the convex hull of the incidence vectors of all hamiltonian circuits and all subsets of these in a complete diagraph of order n. We prove that certain hypohamiltonian diagraphs G=(V,E), i.e. diagraphs which are not hamiltonian but such that G–υ is hamiltonian for all υ?V, induce facets x(E)?n–1 of P?nT. This result indicates that P?nT has very complicated facets and that it is very unlikely that an explicit complete characterization of P?nT can ever be given. 相似文献
24.
We report the first experimental demonstration of an optical quantum controlled-NOT gate without any path interference, where the two interacting path interferometers of the original proposals have been replaced by three partially polarizing beam splitters with suitable polarization dependent transmittance and reflectance. The performance of the device is evaluated using a recently proposed method, by which the quantum process fidelity and the entanglement capability can be estimated from the 32 measurement results of two classical truth tables, significantly less than the 256 measurement results required for full quantum tomography. 相似文献
25.
Hiroaki Yamamoto Youji Kanie Masakazu Arakawa Keiji Taniguchi 《Applied Physics A: Materials Science & Processing》1990,50(6):577-581
The transmission coefficient and the resonance condition in the one-dimensional rectangular double-, triple-, quadruple-, and quintuple-barrier structures are derived theoretically under the assumption of the constant tunneling effective mass. It is found that the resonance energies are different from the eigenvalues in the quantum well due to coupling between wells in the multiple-barrier (much more than triple-barrier) structures. It is confirmed that the transmission spectrum is a Lorentzian near to energies of resonance. 相似文献
26.
M. Fujita T. Endo A. Yamazaki T. Sonada T. Miyake E. Tanaka T. Shinozuka T. Suzuki A. Goto Y. Miyashita N. Sato Y. Wakabayashi N. Hokoiwa M. Kibe Y. Gono T. Fukuchi A. Odahara 《Hyperfine Interactions》2004,159(1-4):245-249
The g-factor of the 27− isomer state of 152Dy has been measured using the Time-Integral Perturbed Angular Distribution (TIPAD) method. The high-spin states of 152Dy have been populated by 141Pr(16O,p4n)152Dy reaction at E = 115 MeV from the AVF cyclotron at CYRIC. The paramagnetic correction factor of Dy ions in Pr has been determined to be
4.2(5) by the Time-Differential Perturbed Angular Distribution (TDPAD) measurement of the 21− state of 152Dy. As a result, the g-factor of the 27− isomer state of 152Dy has been obtained to be +0.09(5). This shows the smaller value than the expected one of +0.39 deduced from a fully aligned
configuration of π(h
11/2
2) ⊗ ν(f
7/2
2
h
9/2
i
13/2). 相似文献
27.
Keiji Kataoka 《Optical Review》2008,15(4):196-203
In the slant scanning method of multiple beams a misalignment of the slant angle causes a beam spacing error and pitch irregularities
of scan lines called “banding”. This paper evaluates the pitch irregularities and tries to clarify the allowable beam spacing
error. The following results are obtained: (1) The maximum spacing error of print lines is proportional to m/(dpi), where m is the number of multiple beams and dpi print dot density. (2) The noticeable limit of periodic variations of print density
at low spatial frequency was presumed to be a visibility between 1 and 2% in experiments. (3) The allowable beam spacing error
was calculated introducing the human eye spatial frequency response. (4) The banding simulation experiments by laser recording
on the photographic paper on the XY stage showed good coincidence with the theoretical evaluations. 相似文献
28.
29.
Magnetite nanoparticles were coated with silica through the hydrolysis and condensation of tetraethyl orthosilicate (TEOS) under ultrasonic irradiation. The ultrasonic irradiation was used to prevent the agglomeration of the magnetite particles and accelerate the hydrolysis and condensation of TEOS. TEM, DLS, XRF, VSM, TG and sedimentation test were used to characterize the silica-coated magnetite particles. The dispersibility of silica-coated magnetite particles in aqueous solution was improved significantly and the agglomerate particle size was decreased to 110 nm. It was found that the agglomerate particle size of silica-coated magnetite particles was mainly decided by the coating temperature and the pH value in the silica-coating process. The weight ratio of silica in silica-coated magnetite particles was mainly decided by the pH value in the silica-coating process. The dispersibility of silica-coated magnetite particles was mainly decided by the agglomerate particle size of the suspension. The oxidation of magnetite particles in air was limited through the coated silica. The magnetism of silica-coated magnetite particles decreased slightly after silica-coating. 相似文献
30.
Kenji Hara Keiji Iwahashi Satoru Takakusagi Kohei Uosaki Masaya Sawamura 《Surface science》2007,601(22):5127-5132
Functionalization of self-assembled monolayer (SAM) of alkanethiolate with metal containing unit is one of the versatile methods to obtain functional surfaces such as heterogeneous catalysts. However, organic molecules that strongly bind to transition metals at SAM terminal are limited. Recently N-heterocyclic carbenes (NHCs) such as cyclic diaminocarbenes have emerged as strongly σ-donating ligands forming a robust bond with broad spectrum of transition metals. In the present study, for the purpose of establishment of a new robust basement for heterogeneous metal catalysts, a SAM of the alkanethiolate terminated with NHC-rhodium(I) complex moiety was prepared by utilizing a newly designed disulfide molecule bearing NHC-metal complex terminals. X-ray photoelectron spectroscopy (XPS) analysis and angle resolved XPS measurement revealed successful formation of the Rh-complex-terminated SAM on a gold substrate. Infrared reflection absorption spectroscopy (IRRAS) analysis suggested that the linker methylene chains connecting the rhodium complex moiety and the gold surface are in a loosely packed structure. This unique chemical species, NHC, would be a promising candidate as a basement for the construction of functional surface. 相似文献