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1.
We present simulation results of the vortex dynamics in a trapped Bose-Einstein condensate in the presence of a rotating optical lattice. Changing the potential amplitude and the relative rotation frequency between the condensate and the optical lattice, we find a rich variety of dynamical phases of vortices. In particular, when the optical lattice rotates faster than the condensate, the competition between the pinning force and the interactions by nucleated interstitial vortices leads to the melting of vortex lattice, yielding a vortex liquid phase.  相似文献   
2.
Advanced sol–gel methods using a secondary solvent addition into (Pb, La)(Zr, Ti)O3 (PLZT) sol–gel solution and a methanol pre-treatment of sapphire substrates are demonstrated. For the secondary solvent addition, the additive affected the crystallinity and electro-optic (EO) property of PLZT films and only methanol addition can improve them. In addition, the methanol pre-treatment is also appeared to be effective to improve film characteristics.

Through these optimizations, epitaxially grown PLZT thin films on r-cut sapphire are obtained and a high Pockels coefficient which is comparable to those of bulk PLZTs is achieved. It is believed that these PLZT thin films are applicable for integrated EO devices and open the door for the future data communication systems.  相似文献   

3.
All animal DNA viruses except pox virus utilize the cell nucleus as the site for virus reproduction. Yet, a critical viral infection process, nuclear targeting of the viral genome, is poorly understood. The role of capsid proteins in nuclear targeting of simian virus 40 (SV40) DNA, which is assessed by the nuclear accumulation of large tumor (T) antigen, the initial sign of the infectious process, was tested by two independent approaches: antibody interception experiments and reconstitution experiments. When antibody against viral capsid protein Vp1 or Vp3 was introduced into the cytoplasm, the nuclear accumulation of T antigen was not observed in cells either infected or cytoplasmically injected with virion. Nuclearly introduced anti-Vp3 IgG also showed the inhibitory effect. In the reconstitution experiments, SV40 DNA was allowed to interact with protein components of the virus, either empty particles or histones, and the resulting complexes were tested for the capability of protein components to target the DNA to the nucleus from cytoplasm as effectively as the targeting of DNA in the mature virion. In cells injected with empty particle-DNA, but not in minichromosome-injected cells, T antigen was observed as effectively as in SV40-injected cells. These results demonstrate that SV40 capsid proteins can facilitate transport of SV40 DNA into the nucleus and indicate that Vp3, one of the capsid proteins, accompanies SV40 DNA as it enters the nucleus during virus infection.  相似文献   
4.
In this paper, we describe two kinds of characteristic nonlinear dynamics in two-component Bose–Einstein condensates. For two overlapping components, we analyzed the collective modes and a variety of nonlinear mode couplings, which were then confirmed by numerical simulation of the time-dependent Gross–Pitaevskii equations. Next, we consider the nonlinear dynamics of two condensates after abruptly turning on the intercomponent coupling strength. For strong intercomponent interactions the out-of-phase density wave of the condensates became unstable, leading to mugtiple domain formation.  相似文献   
5.
We identified the microRNA (miRNA) expression signature of head and neck squamous cell carcinoma (HNSCC) tissues by RNA sequencing, in which 168 miRNAs were significantly upregulated, including both strands of the miR-31 duplex (miR-31-5p and miR-31-3p). The aims of this study were to identify networks of tumor suppressor genes regulated by miR-31-5p and miR-31-3p in HNSCC cells. Our functional assays showed that inhibition of miR-31-5p and miR-31-3p attenuated cancer cell malignant phenotypes (cell proliferation, migration, and invasion), suggesting that they had oncogenic potential in HNSCC cells. Our in silico analysis revealed 146 genes regulated by miR-31 in HNSCC cells. Among these targets, the low expression of seven genes (miR-31-5p targets: CACNB2 and IL34; miR-31-3p targets: CGNL1, CNTN3, GAS7, HOPX, and PBX1) was closely associated with poor prognosis in HNSCC. According to multivariate Cox regression analyses, the expression levels of five of those genes (CACNB2: p = 0.0189; IL34: p = 0.0425; CGNL1: p = 0.0014; CNTN3: p = 0.0304; and GAS7: p = 0.0412) were independent prognostic factors in patients with HNSCC. Our miRNA signature and miRNA-based approach will provide new insights into the molecular pathogenesis of HNSCC.  相似文献   
6.
Goblet cells in the rabbit bulbar conjunctivum were not real "goblet," but were variable in shape. The diversity of the morphology became evident by means of computer-aided three-dimensional reconstruction. All of the cells reconstructed (N = 5) were in touch with the basal lamina, and were open to the epithelial surface. Their cytoplasm was filled with secretory granules (about 71% of the cellular volume, in average), while the nucleus occupied only 5.3%.  相似文献   
7.
A high-power CW TE CO2laser using a new graphite anode structure and a novel Mo wire cathode is described. A uniform discharge for laser excitation is obtained. The device produces a CW output of 6 kW.  相似文献   
8.
We study theoretically the generation of cyclic supercurrent among three superfluids coupled by the Josephson Junctions. Depending on the initial relative phases between superfluids, Josephson current flows cyclically through the superfluids to create a quantized vortex. Reducing the coupling strength changes the motion from periodic to chaotic, thus suppressing the cyclic current. Applying this result to the Kibble-Zurek mechanism, the probability of the vortex generation via this mechanism is modified from the simple estimate given by the geodesic rule. We compare our results with the Lancaster, Grenoble and Helsinki experiments.  相似文献   
9.
We show theoretically the existence of the metastable state and study the decay through the macroscopic quantum tunneling in two-component Bose-Einstein condensates. The numerical analysis of the coupled Gross-Pitaevskii equations clarifies the metastable states whose configuration preserves or breaks the symmetry of the trapping potential, depending on the interspecies interaction and the particle number. We calculate the tunneling decay rate of the metastable state by using the collective coordinate approximation and the bounce technique. It is found that the macroscopic quantum tunneling is observable in a wide range of the particle number.  相似文献   
10.
Ion-trap GC/MS/MS was evaluated for the multi-residue determination of pesticides in agricultural products. Matrices were extracted from samples (spinach, carrot, onion and brown rice) with acetone and submitted to gel permeation chromatography, followed by a clean-up step through a graphite carbon cartridge. Thirty-five pesticides were added to either matrix, and analyzed by GC/MS/MS. Detection limits of pesticides by GC/MS/MS was almost the same as those by GC/MS (SIM). Coefficients of variation of peak area in 5 measurements of each pesticide at 0.1 microgram/mL or 0.05 microgram/mL with or without matrices were mostly acceptable, though those of 20 pesticides out of 35 were higher than 10% at a concentration of 0.02 microgram/mL. It was indicated that matrix artifacts, which interfere with GC/MS-Scan analysis, could be eliminated in some cases by using GC/MS/MS.  相似文献   
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