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31.
Yasuhiro Maeda Masaki Yumoto Norihito Saito Takayo Ogawa Kazuo Kurokawa Akihiko Nakano Masafumi Yamashita Satoshi Wada 《Optical Review》2010,17(3):305-308
We have achieved a rapid and random wavelength tuned picosecond pulsed laser and a widely tunable UV-blue picosecond pulsed
laser by using the intracavity second harmonic generation of the laser. The tuning range was from 384 to 434 nm with picosecond
pulse oscillation. In addition, we demonstrated biological imaging using a fluorescent protein excited by the widely tunable
UV-blue picosecond pulsed laser. We found that the laser is suitable for biological imaging using the fluorescent protein
as an excitation light source without damages. 相似文献
32.
33.
Optically driven actuators have a feature of a non-contact method supplied by light energy. A new method is proposed with
three poly(vinylidene difluoride) (PVDF) cantilevers as the legs and a polymer film as the body. The PVDF cantilevers are
coated with silver on one surface. When one side of the cantilever is irradiated by a laser beam, an electric field is produced
along a cross-section of the cantilever by the pyroelectric effect and a mechanical displacement occurs by the piezoelectric
effect. Its response time and its generated force are measured experimentally. Two types of optically driven actuators using
PVDF film are proposed to move using different characteristics. 相似文献
34.
A multiresolution analysis is adopted to improve an image reconstruction with a phase-diversity technique. The phase distribution at low resolution is first estimated and then is used as an initial estimate for phase reconstruction at a higher resolution level. Computer simulations are conducted to confirm the proposed method. The method is applied for image reconstruction of solar granulation. 相似文献
35.
Hideaki Fujiwara Atsuomi Kimura Yasuhiro Yanagawa Takashi Kamiya Mineyuki Hattori Takashi Hiraga 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2001,150(2):156
Size dependency of the relaxation time T1 was measured for laser-polarized 129Xe gas encapsulated in different sized cavities made by glass bulbs or gelatin capsules. The use of laser-polarized gas enhances the sensitivity a great deal, making it possible to measure the longer 129Xe relaxation time in quite a short time. The size dependency is analyzed on the basis of the kinetic theory of gases and a relationship is derived in which the relaxation rate is connected with the square inverse of the diameter of the cavity. Such an analysis provides a novel parameter which denotes the wall effect on the relaxation rate when a gas molecule collides with the surface once in a second. The relaxation time of 129Xe gas is also dependent on the material which forms the cavity. This dependency is large and the relaxation study using polarized 129Xe gas is expected to offer important information about the state of the matter of the cavity wall. 相似文献
36.
Itaru Hibino Minoru Okita Takayuki Inoue Yasuhiro Banno Masahiro Hoso 《Physical Therapy Research》2008,11(1):1-6
Immobilization is often associated with decreased muscle elasticity. This condition is known as muscle contracture; however, the mechanism remains unclear. The purpose of this study was to clarify the mechanism governing muscle contracture in rat soleus muscle by identifying changes in ankle joint mobility, insoluble collagen concentration and type I and type III collagen isoforms following 1- and 3-week immobilizations. Following a 1-week immobilization, range of motion (ROM) of dorsiflexion declined to 90% of the control value; additionally, ROM dropped to 67.5% of the control value after a 3-week immobilization. This finding suggested that ankle joint mobility decreases in conjunction with extended periods of immobilization. Insoluble collagen concentration in soleus muscles, which was unchanged after 1 week of immobilization, increased 3 weeks after immobilization. These results may be indicative of collagen fibers with strong intermolecular cross-links contained in the muscle was made increased relatively by 3 weeks of immobilization. Therefore, the change in intermolecular cross-links may be significant in terms of progress of muscle contracture with longer periods of immobilization. On the other hand, the ratio of type III to type I collagen isoforms in muscular tissue increased following a 1-week immobilization; moreover, this ratio remained constant after 3 weeks of immobilization. These data suggested that muscle immobilization may induce type III collagen isoform expression. The increase in the ratio of type III to type I collagen isoforms do not change in parallel with the increase in the limitation in ROM; however, this phenomenon probably is not closely related to the progress of muscle contracture. The change of collagen isoform in immobilized muscle may be involved in the mechanism governing the progression of muscle fibrosis. 相似文献
37.
38.
Yoshimitsu K Nishihara Y Okamoto D Ushijima Y Nishie A Yamaguchi K Taketomi A Honda H 《Magnetic resonance imaging》2012,30(6):854-859
Purpose
The aim of this study is to investigate whether subserosal enhancement on the delayed-phase dynamic magnetic resonance (MR) study (SED) can differentiate T2 from T1 gallbladder carcinoma (GBC).Methods
The institutional research board approved this retrospective study. Between 1997 and 2006, there were surgically proven 11 T1 and 21 T2 GBC in 30 patients, all of whom had undergone preoperative contrast enhanced dynamic MR study, either with a 2D sequence (n=17) or 3D sequences (n=15). All images were reviewed by two radiologists for the presence of SED, and receiver operating characteristic (ROC) curve analysis was performed. Sensitivity, specificity, positive and negative predictive values were calculated by consensus.Results
The areas under the ROC curves of the two readers were 0.91 and 0.86, and the kappa value was 0.78. Of the 21 T2 GBC, 18 and 3 showed positive and negative SED, respectively. Of the 11 T1 GBC, 1 and 10 showed positive and negative SED, respectively. The sensitivity, specificity, positive and negative predictive values of SED for diagnosing T2 lesions were 86%, 88%, 91% and 77%, respectively.Conclusions
In conclusion, SED may be a useful sign to differentiate T2 from T1 GBC, which would affect the preoperative surgical planning of the patients. 相似文献39.
Masahiro Aoyama Tomokatsu Hayakawa Sawao Honda Yuji Iwamoto 《Journal of luminescence》2012,132(10):2603-2607
In this research, zeolite-derived aluminosilicate phosphors were synthesized through the ion exchange route. Red light-emitting property of Eu3+-doped aluminosilicate phosphors were discussed from a view point of the Eu content, heat-treatment condition and the oxidation state of Eu ions. The crystalline phase of the host aluminosilicates could be successfully controlled as designed based on the published NaAlO2–SiO2 binary phase diagram. Orange-red emission peaks derived from the 5D0→7Fj (j=0, 1, 2, 3, 4) transition of Eu3+ were observed around 590–700 nm, and 4f65d→4f7 transition of Eu2+ was observed at around 400–500 nm. The relative intensity I(5D0→7F2) of the dominant emission peak at 612 nm increased consistently with the Eu content. The results of the XANES spectroscopy analysis revealed that Eu2+ ion in the 1400 °C as heat-treated host aluminosilicate were successfully converted to Eu3+ by the additional annealing at 1100 °C. The Eu contents and heat-treatment conditions were determined to exhibit the best performance as a red phosphor, which were 10 wt% and 1500 °C, respectively 相似文献
40.
Pulsed laser deposition of iron atoms on graphite substrates was performed to produce iron carbide films. Mössbauer spectra of the sample revealed that iron carbide was produced on the substrate surface and that an α-Fe layer was produced above the iron carbide layer. When the substrate temperature was maintained at 300 K, the iron carbide layer had a hyperfine magnetic distribution because it contained high density of defects. Laser deposition of Fe at 570 K produced cementite Fe3C with fewer defects due to enhancement of thermal reactions or annealing of the films. The orientation of hyperfine field of the Fe3C film was parallel to the substrate surface. 相似文献