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81.
S Kose N Imamoto T Tachibana M Yoshida Y Yoneda 《Canadian Metallurgical Quarterly》1999,274(7):3946-3952
The nuclear export of importin-alpha is mediated by CAS, which is related to importin-beta, whereas the mechanism for the export of importin-beta remains unclear. In this study, we demonstrate that the nuclear export of importin-beta is mediated by the nuclear pore complex-binding domain of this molecule. Insensitivity to leptomycin B indicates that its export is not mediated by a leucine-rich nuclear export signal-specific receptor, CRM1. Furthermore, the nuclear export of importin-beta was not inhibited by co-injection with a GTPase-deficient Ran mutant (G19V). The cell line tsBN2 contains a temperature-sensitive point mutation in the RCC1 gene, which encodes a guanine nucleotide exchange factor of Ran. At the nonpermissive temperature, importin-beta was exported from the nucleus of these cells, even when RanGAP1, a GTPase-activating protein for Ran, was co-injected. These results not only provide support for the view that Ran-dependent GTP hydrolysis is not required for the nuclear export of importin-beta but also indicate that nuclear RanGTP is not essential for its export. As a result, we propose that importin-beta can be recycled from the nucleus alone in a Ran-independent manner. 相似文献
82.
Recently, there has been a lot of work on the production and investigation of the physical properties of Transparent Conducting Oxide (TCO) materials which have common application area in photovoltaic solar cells and some optoelectronic devices. In this work, CdO film which is a material belongs to TCO family has been produced by Ultrasonic Spray Pyrolysis technique on microscope glass substrates at the substrate temperature of 250 ± 5 °C. Electrical, optical, structural and surface properties of undoped and In doped (at 1.3 and 5%) CdO films and the effect of In doping percentage on the physical properties of CdO films have been investigated. It has been determined that electrical conductivity of CdO film is high and this value has been decreased by In doping. After the optical investigations, it has been observed that the transmittances of the films are about 30% and decreased dramatically by In doping. XRD investigations showed that, films have polycrystalline structure and good crystallinity levels. It has been found that In element hasn't got an important effect on the morphology of the films after the examination of surface micrographs. It has been determined that Cd and O elements are present in the solid film by using EDS. After all investigations, it has been concluded that In doping has an important effect on the electrical, optical, structural and surface properties of CdO films. 相似文献
83.
The Shannon capacity of a fading channel under an average-power constraint with channel side information at the transmitter and receiver is only negligibly larger than the capacity of the same channel when constant-power transmission is employed. However, power adaptation has been shown to be quite useful in practical systems, where it has been conjectured that it allows for compensation of the effect of rate quantization. Here, an average bit-error probability constraint is employed instead of the conventional instantaneous bit-error probability constraint. When the set of rates available to the transmitter is unrestricted in practical systems, necessary conditions for jointly optimal power and rate allocation are derived and used to demonstrate that power adaptation is of limited utility. However, when the rates available to the transmitter are restricted to the nonnegative integers for the example of uncoded quadrature amplitude modulation over frequency-nonselective Rayleigh fading channels, a 0.5-0.75 dB loss in power efficiency is incurred when employing only a single power level for each constellation, and a 0.5-bits/symbol loss in rate is incurred when constant power transmission is employed. 相似文献
84.
The objective of this study was to determine certain quality characteristics of the raw and cooked doner kebabs made from beef and sucuk dough which is a traditional fermented sausage. The doners were divided into two groups; traditional beef doners and sucuk dough groups, and all the samples were frozen and stored at (−30 ±1 °C) for 60 days to monitor their quality characteristics. All of the raw and cooked doner samples were subjected to chemical and microbiological analysis while only the cooked doners were evaluated organoleptically at 0th, 30th and 60th days of storage. In the chemical analysis; proximate composition (% moisture, % protein, % fat, and % ash), pH and TBA values were determined. The samples were examined for total aerobic plate count (APC), total anaerobes, psychrotrophic bacteria, total coliforms, total staphylococcus/micrococcus count, mould and yeast to observe the hygienic quality of the doner samples. The results of chemical analysis, in general, showed that sucuk doners had higher ash content, pH and TBA values, and all of the doners had higher APC, psychrotrophic bacteria and coliform counts at the beginning compared to 30th and 60th days of storage not only in the raw condition but also in cooked counterparts. The sensory evaluation results indicated that sucuk doners received favorable preferences, therefore, traditional sausage (sucuk) dough application in doner production could be possible without posing any acceptability problems in terms of quality factors compared to traditional beef doners. 相似文献
85.
Effect of non-aqueous phase liquid on biodegradation of PAHs in spilled oil on tidal flat 总被引:2,自引:0,他引:2
Biodegradation rates of polycyclic aromatic hydrocarbons (PAHs) in spilled oil stranded on tidal flats were evaluated using model reactors to clarify the effects of non-aqueous phase liquid (NAPL) on the biodegradation of PAHs in stranded oil on tidal flat with special emphasis on the relationship between dissolution rates of PAHs into water and viscosity of NAPL. Biodegradation of PAHs in NAPL was limited by the dissolution rates of PAHs into water. Biodegradation rate of chrysene was smaller than that of acenaphtene and phenanthrene due to the smaller dissolution rates. Dissolution rates of PAHs in fuel oil C were smaller than those in crude oil due to high viscosity of fuel oil C. Hence, biodegradation rates of PAHs in fuel oil C were smaller than those in crude oil. Biodegradation rates of PAHs in NAPL with slow rate of decrease like fuel oil C was slower than those in NAPL with rapid rate of decrease like crude oil. The smaller rate of decrease of fuel oil C than crude oil was due to the higher viscosity of fuel oil C. Therefore, not only the dissolution rate of PAHs but also the rates of decrease of NAPL were important factors for the biodegradation of PAHs. 相似文献
86.
87.
Photographs give the impression that they capture reality more truly than other pictorial forms such as drawings and paintings. This study, conducted with 100 operational children ( 5 yrs 10 mo to 7 yrs 3 mo old) and 100 pre-operational children (5 yrs 10 mo to 7 yrs 2 mo old), was concerned with the child's belief as to whether a series of photographs and a parallel series of drawings that depicted illogical or logical outcomes to a conservation of liquid procedure more truly represented reality than directly perceived logical and illogical referent events. Results show the significant influence of the representational medium on fidelity judgments. Six-year-olds treated photographs as having greater fidelity to the reality they depicted than drawings had, but both forms of representation were in general less compelling than real materials themselves. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
BACKGROUND: This study investigated changes in peroxidase (POX) and polyphenol oxidase (PPO) activities through adventitious rooting in hardwood cuttings of grapevine rootstocks. Three grapevine rootstocks with different propensity to produce adventitious roots were selected: recalcitrant (Ramsey), non‐recalcitrant (Rupestris du Lot) and intermediate (99R) cultivars. RESULTS: The averages of root number at 65 days were 96 in Lot, 76 in 99R and 30 in Ramsey. Both enzyme activities characteristically increased before adventitious rooting, regardless of rooting ability of the rootstocks, and then decreased. POX activity increased in Ramsey cuttings at 22 days, in Lot and 99R cuttings at 14 days after planting, and then decreased gradually until 51 days. The highest POX activity was determined in Ramsey rootstock with the highest rooting ability and the lowest activity was determined in the rootstocks with the lowest rooting ability. PPO activity gradually increased in Ramsey rootstock cuttings from 10 days to 22 days, in Lot and 99R cuttings at 14 days, and then decreased until 51 days. A significant correlation was identified between high POX activity and adventitious rooting capability in rootstocks, but the same result was not determined with PPO activity. CONCLUSION: A recalcitrant rooting variety cannot increase POX activity sufficiently before rooting. Therefore applications that could increase POX activity in stem cuttings during rooting may facilitate increased rooting in such rootstocks. Copyright © 2011 Society of Chemical Industry 相似文献