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971.
In this paper we define intuitionistic fuzzy quasi-ideals of ordered semigroups. The main result of the paper is a characterization
of quasi-ideals in terms of intuitionistic fuzzy quasi-ideals. We also characterize left simple, right simple, and completely
regular ordered semigroups in terms of intuitionistic fuzzy quasi-ideals. We study the decomposition of left and right simple
ordered semigroups using intuitionistic fuzzy quasi-ideals. 相似文献
972.
The effects of developing agents and activators in the reversal bleach upon the diffraction efficiencies of a Slavich PFG-01 plate to be used for recording transmission holograms were studied. The plates were developed using four different developers: MSC, AAC, PSC, and HSC. The four developers were derived from different developing agents of metol, l-ascorbic acid, phenidone, and hydroquinone, respectively. Sodium carbonate was added to the developer as an activator that accelerates the development by keeping the developer alkaline. A maximum diffraction efficiency of 89.0% was obtained when the AAC developer was used. 相似文献
973.
Young Beom Kim Ki Hyun Bae Seung-Schik Yoo Tae Gwan Park HyunWook Park 《Magnetic resonance imaging》2009
Objective
The objective of this study was to investigate a method to generate positive contrast, selective to superparamagnetic iron oxide (SPIO) labeled cells, using the susceptibility-weighted echo-time encoding technique (SWEET).Materials and Methods
SPIO-labeled human epidermal carcinoma (KB) cells were placed in a gel phantom. Positive contrast from the labeled cells was created by subtraction between conventional spin-echo images and echo-time shifted susceptibility-weighted images. SPIO-labeled cells were injected into the left dorsal flank and hind limb of nude mice, and unlabeled cells were placed on the right side as controls. Tumor growth was monitored using the proposed method, and a histological analysis was used to confirm the presence of the labeled cells.Results
Based on in vitro testing, we could detect 5000 labeled cells at minimum and the number of pixels with positive contrast increased proportionally to the number of labeled cells. Animal experiments also revealed the presence of tumor growth from SPIO-loaded cells.Conclusions
We demonstrated that the proposed method, based on the simple principle of echo-time shift, could be readily implemented in a clinical scanner to visualize the magnetic susceptibility effects of SPIO-loaded cells through a positive-contrast mechanism. 相似文献974.
975.
976.
Young-Woo Kim Bang Wool Eom Myeong-Cherl Kook Han-Seong Kim Mi-Kyung Kim Hai-Li Hwang Vishal Chandra Shiv Poojan Yura Song Jae-Soo Koh Chang-Dae Bae Jungsil Ro Kyeong-Man Hong 《Experimental & molecular medicine》2015,47(11):e193
Proliferation activity has already been established as a prognostic marker or as a marker for anticancer drug sensitivity. In gastric cancer, however, the prognostic significance of proliferation activity is still being debated. Several studies evaluating proliferation activity using Ki-67 have shown controversial results in terms of the relationship between proliferation activity and overall survival (OS) or drug sensitivity in gastric cancer patients. Because cytoskeleton-associated protein 2 (CKAP2) staining has recently been introduced as a marker of proliferation activity, we analyzed 437 gastric cancer tissues through CKAP2 immunohistochemistry, and we evaluated the chromatin CKAP2-positive cell count (CPCC) for proliferation activity. Although the CPCC did not show any significant correlation with OS in the male, female or total number of cases, it did show a significant correlation in the T1 or T2 male patient subgroup, according to log-rank tests (P=0.001) and univariate analysis (P=0.045). Additionally, multivariate analysis with the Cox proportional hazard regression model showed a significant correlation between the CPCC and OS (P=0.039) for the co-variables of age, gender, T stage, N stage, histology, tumor location, tumor size and adjuvant chemotherapy. In male gastric cancer cell lines, faster-growing cancer cells showed higher sensitivity to cisplatin than slow-growing cells. Thus our study indicates that CPCC-measured proliferation activity demonstrates a significantly worse prognosis in T1 or T2 male gastric cancer patients. The CPCC will help to more precisely classify gastric cancer patients and to select excellent candidates for adjuvant chemotherapy, which in turn will facilitate further clinical chemotherapeutic trials. 相似文献
977.
Jinju Ahn Hyejin Lee Tae‐Hyun Yang Chang‐Soo Kim Byungchan Bae 《Journal of polymer science. Part A, Polymer chemistry》2014,52(20):2947-2957
Multiblock sulfonated poly(arylene ether sulfone)s were synthesized to investigate the structural effects on their membrane properties. Three different types of sulfonated hydrophilic blocks were used; their structures possessed different acidity and local concentration of sulfonic acid groups. For the comparison between the block copolymers, a hydrophobic block with the same chemical structure and block length was used. The different acidities and local concentration were achieved using different sulfonation methods, such as postsulfonation and direct condensation with sulfonated monomers, and different monomers for preparing the hydrophilic block. The higher acidity and concentration of sulfonic acid groups resulted in higher proton conductivity under certain relative humidity conditions and phase separation as shown in the transmission electron microscopy analysis. The synthesized oligomers and polymers were well characterized, and the other physical properties were also investigated. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2947–2957 相似文献
978.
This study seeks to elucidate the interplay of interfirm rivalry and aspiration formation. Organizational aspiration serves as a categorical judgment over a desirable level of organizational performance. While aspiration as a driver of collective decision-making inside the firm is well recognized, our understanding is still limited as to the competitive consequence of aspiration-induced actions. From a computational model of aspiration-induced R&D, where competition is biased towards the status quo, this study suggests that although radical innovation calls for flexibility and diversity inside the firm, aspiration-induced action favors consensus such as a firm with machine bureaucracy either (1) in a market where a majority of consumers are unable to discern a small quality improvement, i.e., demand difficult to satisfy or (2) in a market where competitive advantage dissipates quickly, i.e., an unstable environment. In particular, this study shows that: (1) the level of organizational aspiration has little to do with the sustainability of competitive advantage; (2) aspiration strength—i.e., the extent of consensus among decision makers of the firm as to a legitimate level of organizational aspiration—interacts with the change in competitive advantage. The leading firm is likely to lose its competitive advantage when a follower has a stronger aspiration than the leader in a market whose demand is difficult to satisfy; and (3) the effect of aspiration strength on the sustainability of competitive advantage increases whenever organizational assets depreciate over time. 相似文献
979.
980.