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71.
High resolution thermal expansion measurements on single crystals of κ-(BEDT-TTF)2Cu[N(CN)2]X, with X = Br, Cl, I were performed along the three principal directions in the temperature range from 2 to 300K. The temperature dependence of the linear thermal expansion of the two superconductors (X = Br, Cl) is found to be completely different from that of the non-superconducting I-salt. Cooling the I-crystal, we found an elongation of the c- axis, a larger contraction of the a-axis and a smaller contraction of the b-axis in comparison to the bromide- and the chloride- salt. Common to the three compounds are large anomalies in the linear thermal expansion coefficients i at a temperature Td = 84K, 80K, 73K for X = I, Br, Cl, respectively. The magnitude and the sign of these anomalies in i strongly depend on the anion composition. At Td the i's show steplike changes, which lead to a lattice distortion of opposite sign for the superconductors and for the I-salt. These anomalies indicate a second order phase transition at Td, which eventually may be related to a disorder-order transformation of the terminal ethylene groups of the donor molecules. 相似文献
72.
T Toda S Ikegawa K Okui E Kondo K Saito Y Fukuyama M Yoshioka T Kumagai K Suzumori I Kanazawa 《Canadian Metallurgical Quarterly》1994,55(5):946-950
Fukuyama-type congenital muscular dystrophy (FCMD), the second most common form of childhood muscular dystrophy in Japan, is an autosomal recessive severe muscular dystrophy associated with an anomaly of the brain. After our initial mapping of the FCMD locus to chromosome 9q31-33, we further defined the locus within a region of approximately 5 cM between loci D9S127 and CA246, by homozygosity mapping in patients born to consanguineous marriages and by recombination analyses in other families. We also found evidence for strong linkage disequilibrium between FCMD and a polymorphic microsatellite marker, mfd220, which showed no recombination and a lod score of (Z) 17.49. A "111-bp" allele for the mfd220 locus was observed in 22 (34%) of 64 FCMD chromosomes, but it was present in only 1 of 120 normal chromosomes. This allelic association with FCMD was highly significant (chi 2 = 50.7; P < .0001). Hence, we suspect that the FCMD gene could lie within a few hundred kilobases of the mfd220 locus. 相似文献
73.
Masatsune Kato Takaaki Aoki Takashi Noji Yasuhiro Ono Yoji Koike Tomoyuki Hikita Yoshitami Saito 《Journal of Superconductivity》1994,7(1):37-38
We have investigated the relation between the crystal structure and superconductivity in La1.9Bi0.1CuO4+
, in which the phase separation observed in La2CuO4+
is suppressed. A phase diagram in theT– plane is given for La1.9Bi0.1CuO4+
with excess oxygen. For very small values, the crystal structure is orthorhombic, and an orthorhombic-tetragonal phase transition occurs markedly at 0.03 in the measured temperature range between 13 and 293 K. Superconductivity is observed in the range of 0.04<<0.11. This is clear evidence thathigh-T
c
superconductivity also appears in the tetragonal phase. 相似文献
74.
B.D. Smith (ibid., vol.MI-4, p.15-25, 1985; Opt. Eng., vol.29, p.524-34, 1990) and P. Grangeat (These de doctorat, 1987; Lecture Notes in Mathematics 1497, p.66-97, 1991) derived a cone-beam inversion formula that can be applied when a nonplanar orbit satisfying the completeness condition is used. Although Grangeat's inversion formula is mathematically different from Smith's one, they have similar overall structures to each other. The contribution of the present paper is two-fold. First, based on the derivation of Smith, the authors point out that Grangeat's inversion formula and Smith's one can be conveniently described using a single formula (the Smith-Grangeat inversion formula) that is in the form of space-variant filtering followed by cone-beam back projection. Furthermore, the resulting formula is reformulated for data acquisition systems with a planar detector to obtain a new reconstruction algorithm. Second, the authors make two significant modifications to the new algorithm to reduce artifacts and numerical errors encountered in direct implementation of the new algorithm. As for exactness of the new algorithm, the following fact can be stated. The algorithm based on Grangeat's intermediate function is exact for any complete orbit, whereas that based on Smith's intermediate function should be considered as an approximate inverse excepting the special case where almost every plane in 3D space meets the orbit. The validity of the new algorithm is demonstrated by simulation studies. 相似文献
75.
Taiju Takahashi Yukihiro Kudoh Yuichi Saito Yoshihiro Aoyagi 《Journal of the Society for Information Display》2023,31(3):101-111
Recently, there has been considerable research on optical devices, such as liquid crystal (LC) lenses and special optical plates, using LCs. In such devices, relatively small LC cells are frequently used, or unique LC orientations are required. As an LC orientation process, we focused on the LC director's orientation induced by the magnetic force line distribution of a small neodymium magnet. We propose a simple method for obtaining radial orientation, which is rather difficult to obtain using the ordinary rubbing method. The initial orientation in the LC cell is a vertical orientation cell with almost zero azimuth anchoring. With the proposed method, the reorientation process is performed with an assisting electric field and a small permanent magnet, unlike the conventional magnetic field orientation process that requires a large electromagnet. Furthermore, a polymer stabilization treatment is used to fix the obtained radial orientation pattern in the LC cell. After the treatment, the applying voltage can control the tilt angle of the director in weak polymer treatment, and a completely fixed orientation pattern can be obtained that in strong. 相似文献
76.
Takeo Uchida Keita Abe Yuma Endo Shosei Ichiseki Satoru Akita Shiyun Liu Sho Aradachi Masataka Saito Akihiko Fukuchi Taiyo Kikkawa Theo Dammaretz Ibuki Kawamata Yuki Suzuki Shin‐ichiro M. Nomura Satoshi Murata 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(41)
A new kind of the Vernier mechanism that is able to control the size of linear assembly of DNA origami nanostructures is proposed. The mechanism is realized by mechanical design of DNA origami, which consists of a hollow cylinder and a rotatable shaft in it connected through the same scaffold. This nanostructure stacks with each other by the shape complementarity at its top and bottom surfaces of the cylinder, while the number of stacking is limited by twisting angle of the shaft. Experiments have shown that the size distribution of multimeric assembly of the origami depends on the twisting angle of the shaft; the average lengths of the multimer are decamer, hexamer, and tetramer for 0°, 10°, and 20° twist, respectively. In summary, it is possible to affect the number of polymerization by adjusting the precise shape and movability of a molecular structure. 相似文献
77.
Y Tanaka K Fujii S Hübscher M Aso A Takazawa K Saito T Ota S Eto 《Canadian Metallurgical Quarterly》1998,41(8):1365-1377
OBJECTIVE: To clarify the role of heparan sulfate proteoglycan (HSPG) and chemokines in integrin-mediated T cell adhesion to endothelial cells in the synovium of patients with rheumatoid arthritis (RA). METHODS: Endothelial cells were purified from RA synovium. Expression of heparan sulfate, chemokines, and adhesion molecules on the endothelium was assessed by immunohistochemical analysis or flow cytometry. The effects of chemokines and heparan sulfate on T cell adhesion to RA endothelium were estimated with relevant antibodies and signaling inhibitors. Production of chemokines from synovial T cells was detected by Northern blotting and enzyme-linked immunosorbent assay. RESULTS: The endothelium in RA synovium highly expressed HSPG. The soluble form of chemokines, macrophage inflammatory protein 1beta (MIP-1beta), induced T cell adhesion to the endothelial cells. When MIP-lalpha and MIP-1beta were immobilized on RA endothelial cells, a more efficient integrin-mediated adhesion of T cells was induced compared with their soluble form. The induced T cell adhesion was reduced by pretreatment with either heparitinase, anti-MIP-lalpha antibody, or anti-MIP-lbeta antibody, indicating that these chemokines were bound to heparan sulfate on the cells. T cell adhesion was also inhibited by pertussis toxin, wortmannin, and cytochalasin B. MIP-lalpha and MIP-1beta were found on vessels in RA synovium in vivo, which were spontaneously produced from T cells purified from RA synovium. CONCLUSION: Endothelial cells in RA synovium characteristically express HSPG, which is involved in T cell integrin triggering by "posting" chemokines, which are produced by synovial T cells, and by "relaying" them to their receptors on T cells, which activate G protein-dependent phosphoinositide 3-kinase and actin-dependent integrin triggering. 相似文献
78.
T Saito T Nakahara Y Abe T Sugiura M Ogata Y Sugiyama T Watanabe M Honma C Hida T Yamamoto 《Canadian Metallurgical Quarterly》1998,50(12):1133-1141
BACKGROUND: This article presents results of the acute treatment phase of a 2-site study comparing cognitive behavioral group therapy (CBGT) and treatment with the monoamine oxidase inhibitor phenelzine sulfate for social phobia. METHODS: One hundred thirty-three patients from 2 sites received 12 weeks of CBGT, phenelzine therapy, pill placebo administration, or educational-supportive group therapy (an attention-placebo treatment of equal credibility to CBGT). The "allegiance effect," ie, the tendency for treatments to seem most efficacious in settings of similar theoretical orientation and less efficacious in theoretically divergent settings, was also examined by comparing responses to the treatment conditions at both sites: 1 known for pharmacological treatment of anxiety disorders and the other for cognitive behavioral treatment. RESULTs: After 12 weeks, phenelzine therapy and CBGT led to superior response rates and greater change on dimensional measures than did either control condition. However, response to phenelzine therapy was more evident after 6 weeks, and phenelzine therapy was also superior to CBGT after 12 weeks on some measures. There were few differences between sites, suggesting that these treatments can be efficacious at facilities with differing theoretical allegiances. CONCLUSIONS: After 12 weeks, both phenelzine therapy and CBGT were associated with marked positive response. Although phenelzine therapy was superior to CBGT on some measures, both were more efficacious than the control conditions. More extended cognitive behavioral treatment and the combination of modalities may enhance treatment effect. 相似文献
79.
Takashi Noji Yoji Koike Hideo Iwasaki Masatsune Kato Norio Kobayashi Yoshitami Saito 《Journal of Superconductivity and Novel Magnetism》1996,9(1):65-71
Anisotropie properties of the single crystal Pb2Sr2Ho0.5Ca0.5Cu3O8 have been investigated by measuring the electrical resistivity in theab-planeρ ab (H, θ,T), which depends on the angleθ between theab-plane and the magnetic-field direction, in various constant fieldsH perpendicular to the current direction. All the angle-dependent values ofρ ab (H, θ,T) at a constant temperature are scaled to be on one curve as a function of reduced field. The anisotropic parameter γ≡(m c * /m ab * )1/2 is estimated as 12–13, which is larger than that of YBa2Cu3O7 and much smaller than that of Bi2Sr2CaCu2O8. It has been concluded that the anisotropy does not always depend on the thickness of the blocking layer but seems to depend on the overlap of the electronic wave functions along thec-axis. Anisotropy in the pinning potential has also been discussed from the resistive tail in the temperature dependence ofρ ab (H,θ,T). 相似文献
80.