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21.
We propose a new fringe analysis method that uses only one speckle interferogram of a deformed object to obtain phase change distribution by deformation. This method uses cos-1 operations to extract absolute, not signed, values of new phase after deformation. Considering the phase changes in a small local area, true phase changes retain almost the same value by assuming a continuous deformation in the area. This retention determines the sign of the new phase. From the new phase and the initial phase, the phase change distribution by the deformation can be obtained. Experimental results show the usefulness of this method.  相似文献   
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23.
The extracellular matrix protein Pl-nectin, a 210-kDa homodimer originally purified from sea urchin eggs, plays a crucial role in cell adhesion and embryonic morphogenesis. The compiled cDNA sequence, obtained by RT-PCR primer walking and 3′ RACE, identified a 984aa product containing a 23aa signal peptide and including all six internal peptides identified by protein microsequencing. The protein is a new member of the galactose-binding protein superfamily as it consists of six 151–156aa-long tandemly repeated domains (D1–D6), homologous to the discoidin-like domains, also known as F5/8-type C domains. Based on homology modelling, we present a three-dimensional structure (3D) for D5, identified as the prototype domain. The molecular modelling of the assembled Pl-nectin homodimer accounts for a Pl-nectin quaternary structure composed of two 105-kDa C-shaped monomers linked by a S–S bridge. The presence of an LDT motif between the first and the second exposed loops of the D2 domain suggests the binding of Pl-nectin to an integrin receptor. Altogether, the in silico analysis described here is consistent with previous biochemical reports and offers a basis for predictions to be experimentally tested.  相似文献   
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25.
A topological superconductor (TSC) is characterized by the topologically protected gapless surface state that is essentially an Andreev bound state consisting of Majorana fermions. While a TSC has not yet been discovered, the doped topological insulator Cu(x)Bi(2)Se(3), which superconducts below ~3 K, has been predicted to possess a topological superconducting state. We report that the point-contact spectra on the cleaved surface of superconducting Cu(x)Bi(2)Se(3) present a zero-bias conductance peak (ZBCP) which signifies unconventional superconductivity. Theoretical considerations of all possible superconducting states help us conclude that this ZBCP is due to Majorana fermions and gives evidence for a topological superconductivity in Cu(x)Bi(2)Se(3). In addition, we found an unusual pseudogap that develops below ~20 K and coexists with the topological superconducting state.  相似文献   
26.
It was shown that ubiquinone (CoQ10) and ubiquinol (CoQ10H2) produce fluorescence products under alkaline conditions when reacted with 2-cyanoacetamide. The reaction mixture from CoQ10 gave fluorescence with excitation and emission maximum wavelengths at 442 nm and 549 nm, respectively. This reaction was considered to proceed via Craven’s reaction. Moreover, 2-cyanoacetamide was shown to be a useful reagent for high-performance liquid chromatography (HPLC) with post-column fluorescence derivatization of CoQ10 and CoQ10H2 in blood. CoQ10 showed a linear response in the range of 0.32–1276 ng, and the detection limit (S/N = 3) was 0.16 ng. Moreover, the sample pretreatment by deproteinization and extraction of CoQ10 and CoQ10H2 from plasma using 1-propanol with potassium formate was effective for excellent separation of CoQ10 and CoQ10H2 from other fluorescent substances in the blood. This simple and rapid pretreatment was considered to minimize the oxidation of CoQ10H2. On the other hand, CoQ10 and CoQ10H2 in plasma samples obtained by finger prick were detected, as in venous blood obtained by venipuncture. Our method involving the simple and rapid collection of plasma by finger prick and sample pretreatment is thought to be applicable for the determination of CoQ10H2/total CoQ10 ratio as a biomarker of oxidative stress.  相似文献   
27.
In order to clarify the tunneling spectroscopy in high-Tc cuprates, we study electronic state of the surface in the strongly correlated electron systems. First, we obtain Green's function of strongly correlated normal bulk system using the fluctuation exchange (FLEX) approximation. Next, we insert infinite potential into the bulk system and obtain Green's function of surface. We find that the density of states (DOS) in strongly correlated bulk systems are different from that on the surface, and the difference decreases as the magnitude of Coulomb interaction (U) increases.  相似文献   
28.
The Capitanian (Late Guadalupian) Maokou Formation at Chaotian in northern Sichuan, South China, is composed mainly of shallow marine shelf carbonates deposited on the Tethyan side of South China. By detailed field mapping and scientific drilling, we newly found out unique fossil assemblages and a sharp lithologic change in the upper part of the Maokou Formation. The main part of the Maokou Formation (over 130 m thick) is composed of algal packstone with Wordian-Capitanian large-tested fusulines, rugose corals and other sessile benthos, whereas the Uppermost Member (13 m thick) is composed of black limy mudstone/chert with Capitanian offshore biota (ammonoids, radiolarians, and conodonts). The topmost Capitanian conodont zones are missing; however, the Maokou Formation is disconformably overlain by 260+/-4 Ma volcanic ash (Wangpo bed) and the Early Lopingian Wujiaping Formation with plant-bearing coaly mudstone and shallow marine carbonates (packstone). The newly identified facies change indicates that northern Sichuan has experienced rapid sea-level changes in the late Guadalupian, i.e., first a transgression in the mid-Capitanian and then a regression across the Guadalupian-Lopingian boundary. As the end-Guadalupian is characterized by a global regression, such a volatile sea-level fluctuation, in particular the sea-level rise, is unique to the Tethyan side of South China. The newly recognized relatively deep-water late Guadalupian sequence adds new paleo-environmental information and further provides a paleotectonic interpretation of the low-latitude eastern Tethyan margin immediately before the end-Guadalupian mass extinction.  相似文献   
29.
We study the local density of states at the surface of a chiral p-wave superconductor in the presence of a weak magnetic field. As a result, the formation of low-energy Andreev bound states is either suppressed or enhanced by an applied magnetic field, depending on its orientation with respect to the chirality of the p-wave superconductor. Similarly, an Abrikosov vortex, which is situated not too far from the surface, leads to a zero-energy peak of the density of states, if its chirality is the same as that of the superconductor, and to a gap structure for the opposite case. We explain the underlying principle of this effect and propose a chirality sensitive test on unconventional superconductors.  相似文献   
30.
Angular correlation of two-photon annihilation radiation (ACAR) measurements have been performed to study the effect of interstitial impurities (O, C and D) on positronium (Ps) formation in irradiation-induced voids of vanadium. It has been observed that Ps formation is sensitively affected by doping with the interstitial impurities, irradiation dose, irradiation temperature, and also by post-irradiation annealing. The Ps component intensity is found to be related to segregation of the interstitial impurities and provides a new experimental method to study void surfaces.  相似文献   
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