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571.
572.
We describe a method for in situ sizing individual huge DNA molecules by laser trapping. Single DNA molecules are reversibly transformed, without mechanical fragmentation of fragile huge-sized DNA, from their random coil state into their globular state induced by condensing agents poly(ethylene glycol) and Mg(2+). With the use of a globular DNA molecule folded by condensation, the critical velocity of the circularly accelerated single globular DNA molecule by laser trapping was found to be proportional to the size of the DNA. Yeast, Saccharomyces cerevisiae, chromosome III (285 kbp) was successfully sized (281 +/- 40 kbp) from a calibration curve scaled using lambda, T4, and yeast chromosome VI (48.5, 166, and 385 kbp, respectively). The use of critical velocity as a sizing parameter makes it possible to size single DNA molecules without prior conformational information, i.e., the radius of a single globular huge DNA molecule as a nanoparticle. A sized single globular DNA molecule could be trapped again for subsequent manipulation, such as transportation of it anywhere. We also investigated a possibility of reusing the globular DNA molecules condensed by PEG and Mg(2+) for PCR and found that PCR efficiency was not deteriorated in the presence of the condensation agents. 相似文献
573.
Mitsuru Kihara Masaru Okada Makoto Hosoda Tomoyuki Iwata Yuichi Yajima Masanobu Toyonaga 《Optical Fiber Technology》2012,18(6):470-479
We investigated and analyzed faults in field installable connection due to incorrectly cleaved fiber ends and manufactured physical contact (PC)-type connectors with contaminated end surfaces in optical access fiber networks. The insertion and return losses of fiber connections using incorrectly cleaved fiber ends might be at worst more than 40 dB and less than 30 dB, respectively. With PC-type connectors whose end surfaces are contaminated, the insertion and return losses might be at worst 8.7 and 27 dB, respectively. We developed an inspection tool for cleaved fiber ends and connector end surfaces as a countermeasure. The proposed tool has a simple structure and does not require focal adjustment. It can be used to inspect and clearly determine whether a fiber has been cleaved correctly and whether there is contamination or scratches on the connector end surfaces. The tool requires a slight increase of 11% in operation time compared to conventional fiber end preparation and assembly procedures. The proposed tool provides a simple and cost-effective way to inspect cleaved fiber ends and connector end surfaces and is suitable for field use. 相似文献
574.
To elucidate a functional transformation of gastric parietal cells, we have newly developed an isolated rat gastric mucosa model whose parietal cells exhibited a reverting process from the active to the resting state of acid secretion. Briefly, the parietal cells were treated with cimetidine following prior stimulation of acid secretion in the model, and cryofixed by plunge freezing for light microscopy or high-pressure freezing for electron microscopy. As a result, immunohistochemistry of H(+)/K(+)-ATPase demonstrated a progressive translocation of H(+)/K(+)-ATPase from the apical to the cytoplasmic region. The ultrastructure of parietal cells at 5 min in the reverting phase was quite similar to that of maximally stimulated one. However, the apical microvilli of intracellular canaliculi (IC) changed bulbous by degrees, resulted in complete occlusion of IC at 60 min in the reverting phase. The apical membranes were subsequently internalized into the cytoplasm forming unique penta-laminar membranes. Interestingly, at 90 min in the reverting phase, the penta-laminar membranes formed a number of multilamellar autophagosomes that were intensely labeled for H(+)/K(+)-ATPase. Then, the parietal cells exhibited well-developed Golgi apparatus and lysosomal compartments involving the multilamellar membranes at 105 min, and mostly reverted to their resting conformation at 120 min in the reverting phase. Corresponding to the ultrastructural changes of microvilli, the immunohistochemistry of ezrin showed a dissociation of ezrin from the apical region at 30 min in the reverting phase. The present findings provide new insights into the functional transformation in gastric parietal cells reverting to their resting conformation. 相似文献
575.
Alena Neviarouskaya Helmut Prendinger Mitsuru Ishizuka 《International journal of human-computer studies》2010,68(7):432-450
Social interaction among people is an essential part of every society, and a strong foundation for the development and self-actualization of a person. Even in virtual environments we tend to interact in a social way. Our research addresses the tasks of recognition, interpretation, and visualization of affect communicated through text messaging. In order to facilitate sensitive and expressive interaction in computer-mediated communication, we previously introduced a novel syntactical rule-based approach to affect recognition from text. The evaluation of the developed Affect Analysis Model showed promising results regarding its capability to accurately recognize affective information in text from an existing corpus of informal online conversations. To enrich the user's experience in online communication, to make it enjoyable, exciting, and fun, we implemented a web-based Instant Messaging (IM) application, AffectIM, and endowed it with emotional intelligence by integrating the developed Affect Analysis Model. This paper describes the findings of a twenty-person study conducted with our AffectIM system. The results of the study indicate that our IM system with automatic emotion recognition function can achieve a level of affective intelligence (system is successful at conveying the user's feelings, avatar expression is appropriate) that is comparable to “gold standard”, where users select the label of the conveyed emotion manually. 相似文献
576.
We consider the problem of selecting the populations associated with the (1≤s<k) largest location parameters out of k(≥2) independent populations with a common scale parameter, while satisfying the preassigned probability requirement exactly and enjoying second-order properties simultaneously. Two distributional cases are considered: i Normal distribution; and ii negative exponential distribution. A twostage procedure is proposed to give such a selection rule for each case of (i)-(ii) under Mukhopadhyay and Duggan's (1999) assumption. The design constant in the proposed procedure is tabulated compared with rhe corresponding approximate value which is computed by using an asymptotic expansion formula 相似文献
577.
Shin-ichi Sawada Mitsuaki Goto Hiroshi Koshikawa Akane Kitamura Mitsuru Higa Tetsuya Yamaki 《分离科学与技术》2020,55(12):2211-2216
ABSTRACT For high-performance electrodialysis of saline water, cation exchange membranes (CEMs) that actively transport Na+ and restrict water permeation are required. In this study, we prepared novel CEMs by a heavy-ion-track grafting technique and measured their membrane resistance and water permeation flux as transport properties. The prepared nanostructured CEMs exhibited lower resistance and lower water flux than the commercial CEM. Na+ ions were efficiently transported through their unique one-dimensional ion channels (low resistance), while water transport was suppressed due to the very low water uptake of the CEMs. These results demonstrated the high potential of these nanostructured CEMs for use in practical saline water electrodialysis. 相似文献
578.
We investigated by Transmission Electron Microscopy (TEM) the morphologies of crosslinked copolymers from methacrylate monomers from methylmethacrylate (MMA) and trifluoroethylmethacrylate (TFEMA), polydimethylsiloxane (PDMS) macromers with molecular weight (Mn) of 1,700 and 4,700 g/mol, and crosslinker. Depending on the PDMS content, we observed, spherical PMMA islands in which small PDMS domains were dispersed, PMMA continuous phase, closely packed PTFEMA islands, and homogeneously dispersed PDMS domains were observed with low or middle magnification. Fine observation at 100,000‐fold magnification revealed the “fundamental” common size domain, which was determined by the Mn value of the PDMS macromer. Thus we found two microstructure types: (1) a “fundamental domain” due to the Mn of the PDMS macromer, and (2) an aggregated domain. The former was constant under all conditions, but the latter was affected by the comonomer and its ratio. The present results are essential in understanding the chemical and physical characteristics of crosslinked copolymers from PDMS macromers. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
579.
Akio Kishida Takashi Kanda Tsutomu Furuzono Ikuro Maruyama Mitsuru Akashi 《应用聚合物科学杂志》2000,78(12):2198-2205
A blending technique was studied in order to widen the applications of aramid–silicone multiblock copolymer (PAS). A PAS/aramid blend film was prepared and the characterization of the surfaces was investigated. The two‐phase nature of poly(dimethylsiloxane) (PDMS) and the aromatic polyamide (aramid) multiblock copolymer (PAS) were clarified in part by evaluating the surface enrichment in PAS/aramid blend films. There were no significant differences among the PASs as additives; however, the PASs were able to alter the aramid surface to that of silicone, even though they were used at low concentration. The atomic force microscopy observation suggested that the mobility of the silicone segment that existed on the surface was restricted by the associated aramid segments. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 2198–2205, 2000 相似文献
580.
Three crude glucoamylase preparations from Rhizopus sp., Chalara paradoxa and Aspergillus sp. K-27 were used to determine the digestibility of raw starches from eight sweet potato varieties. Granule sizes and amylose contents were also measured. The average granule sizes ranged between 10.5 and 14.2 μm. The amylose contents varied between 18.2 and 21.8%. The hydrolysis rates for the raw starches by any of the three glucoamylases were similar. However, starch of the variety Hi-starch had a slightly lower hydrolysis rate than other starches when Rhizopus sp, enzyme was used. 相似文献