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51.
HPLC analysis revealed that eight subsidiary colors existed in commercial Food Green No. 3 (fast green FCF, FD & C Green No. 3). Among them, four subsidiary colors C, F, G, and H were isolated by using preparative HPLC and their structures were determined by MS and NMR. They were the disodium salt of 2-[[4-[N-ethyl-N-(3- sulfophenylmethyl)amino]phenyl][4-[N-ethyl-N-(4- sulfophenylmethyl)amino]phenyl]methylio]-4-hydroxybenzenesulfonic acid (abbreviated as m,p-G-3), the sodium salt of 2-[[(4-N-ethylamino)phenyl][4-[N-ethyl-N-(3- sulfophenylmethyl)amino]-phenyl]methylio]-4-hydroxybenzenesulfonic acid [abbreviated as HSBA-(EA) (m-EBASA)], the sodium salt of 2-[[(4-N-diethylamino)phenyl][4-[N-ethyl-N-(3- sulfophenylmethyl)amino]phenyl]-methylio]-4-hydroxybenzenesulfonic acid [abbreviated as HSBA-(di-EA) (m-EBASA)], and the sodium salt of 2-[[4-[N-ethyl-N-(phenylmethyl)amino]phenyl][4-[N-ethyl-N-(3- sulfophenylmethyl)-amino]phenyl]methylio]-4-hydroxybenzenesulfonic acid [abbreviated as HSBA-(EBA)(m-EBASA)], respectively. HSBA-(di-EA) (m-EBASA) was a subsidiary color newly found in commercial Food Green No. 3.  相似文献   
52.
The oil spill has caused significant attention on a global scale due to its damage to the environment and the economy. The development of economically and ecologically friendly oil sorbent materials has important meaning for the oil spill concern. In this work, we explored the non-solvent impacted thermally induced phase separation (NITIPS) method to prepare the cellulose triacetate aerogel (CA) with low density (6.4–40.5 mg/cm3), high porosity (96.9–99.5%), large water contact angle (>129°) and high specific surface area (193–573 m2/g) as the oil sorbent material. The oil absorption capacity of CA with vegetable oil and vacuum pump oil reached 80.8 g/g and 38.9 g/g, respectively, consistent with Fick's law of diffusion. Moreover, the NITIPS method provided simpler process and controlled the shape of CA compared with the traditional thermally induced phase separation method. This study proved that the CA prepared by NITIPS methods played an important role as a potential oil absorption solids in the field of oil spill and organic chemical leakage.  相似文献   
53.
Catenins are proteins associated with the cytoplasmic domain of cadherins, a family of transmembrane cell adhesion molecules. The cadherin-catenin adhesion system is involved in morphogenesis during development and in the maintenance of the integrity of different tissue types. Using a gene trap strategy, we have isolated a mouse mutation for the gene encoding the alpha-E-catenin. This form of the alpha-catenin appears frequently coexpressed with E-cadherin in epithelial cell types. The mutation obtained eliminates the carboxyl-terminal third of the protein but nevertheless provokes a complete loss-of-function phenotype. Homozygous mutants show disruption of the trophoblast epithelium (the first differentiated embryonic tissue), and development is consequently blocked at the blastocyst stage. This phenotype parallels the defects observed in E-cadherin mutant embryos. Our results show the requirement of the alpha-E-catenin carboxy terminus for its function and represent evidence of the role of the alpha-E-catenin in vivo, identifying this molecule as the natural partner of the E-cadherin in trophoblast epithelium.  相似文献   
54.
This study was designed to examine the scale quality of our newly developed short behavior scale and to identify its role in predicting the functional outcome of stroke patients. The short behavior scale consists of six items that assess cognitive function related to the daily behavioral status of a patient in activities of daily living and exercise. It can be scored quickly through observation of a patient's behavior. We assessed 190 stroke inpatients, who had a mean age of 61 years. The mean days and length of stay from onset were 47.3 and 138.2, respectively. We examined internal consistency with the Cronbach's alpha coefficient. Interrater reliability was tested by having two examiners evaluate 30 patients independently. We studied how the short behavior scale correlated with the admission Functional Independence Measure, Mini-Mental State Examination scores, and speech and visuospatial functions. We also studied how the short behavior scale contributed to the prediction of discharge Functional Independence Measure raw scores with stepwise multiple regression analysis. In another group of 116 patients, we cross-validated our predictive equation. The Cronbach's alpha coefficient was 0.88. The intraclass correlation coefficient was 0.84 for total score. The short behavior scale correlated significantly with cognitive Functional Independence Measure scores and Mini-Mental State Examination scores. We could explain 70.8% of the variance of discharge Functional Independence Measure scores from the Short Behavior Scale, days from onset to admission, age, speech scores, and admission Functional Independence Measure scores. Stability of the predictive equation was shown in cross-validation to a second sample of 116 patients. In conclusion, our newly developed short behavior scale proved reasonable and would be useful to enhance the precision of outcome prediction in stroke rehabilitation.  相似文献   
55.
利用反共振控制原理 ,提出了基于形状记忆合金 (Shape Memory Alloy— SMA)的转子系统振动的反共振控制策略 ,其主要思路是将 SMA弹簧并联形成转子轴承的支撑部分 ,并通过 SMA弹簧刚度变化改变转子轴承刚度 ,从而使转子处于反共振状态 ,达到振动控制的目的。最后通过数值仿真初步验证了方法的有效性  相似文献   
56.
In the yeast Saccharomyces cerevisiae, the yeast episomal plasmid (YEp), containing a partial sequence from a natural 2-μm plasmid, has been frequently used to induce high levels of gene expression. In this study, we used Japanese sake yeast natural cir0 strain as a host for constructing an entire 2-μm plasmid with an expression construct using the three-fragment gap-repair method without Escherichia coli manipulation. The 2-μm plasmid contains two long inverted repeats, which is problematic for the amplification by polymerase chain reaction. Therefore, we amplified it by dividing into two fragments, each containing a single repeat together with an overlapping sequence for homologous recombination. TDH3 promoter-driven yEmRFP (TDH3p-yEmRFP) and the URA3 were used as a reporter gene and a selection marker, respectively, and inserted at the 3′ end of the RAF1 gene on the 2-μm plasmid. The three fragments were combined and used for the transformation of sake yeast cir0 ura3- strain. The resulting transformant colonies showed a red or purple coloration, which was significantly stronger than that of the cells transformed with YEp-TDH3p-yEmRFP. The 2-μm transformants were cultured in YPD medium and observed by fluorescence microscopy. Almost all cells showed strong fluorescence, suggesting that the plasmid was preserved during nonselective culture conditions. The constructed plasmid maintained a high copy state similar to that of the natural 2-μm plasmid, and the red fluorescent protein expression was 54 fold compared with the chromosomal integrant. This vector is named YHp, the Yeast Hyper expression plasmid.  相似文献   
57.
Disulfide-rich peptides have found widespread use in the development of bioactive agents; however, low proteolytic stability and the difficulty of exerting synthetic control over chain topology present barriers to their application in some systems. Herein, we report a method that enables the creation of artificial backbone (“foldamer”) mimics of compact, disulfide-rich tertiary folds. Systematic replacement of a subset of natural α-residues with various artificial building blocks in the context of a computationally designed prototype sequence leads to “heterogeneous-backbone” variants that undergo clean oxidative folding, adopt tertiary structures indistinguishable from that of the prototype, and enjoy proteolytic protection beyond that inherent to the topologically constrained scaffold. Collectively, these results demonstrate systematic backbone substitution to be a viable method to engineer the properties of disulfide-rich sequences and expands the repertoire of protein mimicry by foldamers to an exciting new structural class.  相似文献   
58.
This ultrastructural study showed that nonisotopic methanolic hafnium chloride and aqueous lead solution was an excellent new electron stain for enhancing TEM contrasts of fungal and plant cell structures. The ultrastructural definition provided by the new stain was often superior to that provided by conventional staining with uranyl acetate and lead. Definition of fine ultrastructure was also supported by quantitative data on TEM contrast ratios of organelles and components in fungal and plant cells. In particular, polysaccharides, which were localized in cell walls, glycogen particles, starch grains, and plant Golgi vesicle components, were much more reactive to the new stain than to the conventional one. The new nonisotopic stain is useful for enhancing the contrast of ultrastructure in biological tissues and is a safer alternative to uranyl acetate. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
59.
Test sheets were prepared by incorporating softwood pulp with silica filler, PW‐5 (diameter 4.5 μm) or PW‐20 (15 μm). Length‐weighted averages of fibre were 2.5 (uncut fibre) and 1.25 mm (short‐cut fibre). Pore sizes less than 150 urn were measured by mercury porosimeter. Sheets of short‐cut fibres and mixed with uncut fibres at ratio of 3:1 or 1:3 had larger pore volumes than others tested. When filler content increased, the total pore volume increased for PW‐20 sheets, but it did not for PW‐5 sheets with short‐cut fibres. Tensile index and folding endurance were very much affected by fibre length. Contact number on a fibre was calculated by computer simulation, and it had a linear relation with tensile index of sheet.  相似文献   
60.
It has been reported that 2-ethyl-1-hexanol (2E1H) was emitted through hydrolysis between di-2-ethylhexyl phthalate used as plasticizer in flooring material and moisture generated from a strongly alkaline material such as concrete slab. The purpose of this study was to clarify the relationship between diffusion of 2E1H in flooring material and 2E1H emission rate from floor surface. In this study, we measured 2E1H emitted from floor paper, poly(vinyl chloride) (PVC) tile, cushion floor and carpet for 200,?days and effective diffusion coefficients for 2E1H in various flooring materials were measured. Effective diffusion coefficients of 2E1H for cushion floor and PVC tile were 115?×?10?9 and 7.8?×?10?9 m2/s, respectively. Emission rate of 2E1H emitted from flooring material significantly depends on the kind and shape of flooring materials and was influenced by the effective diffusion coefficient for 2E1H of flooring material. Emission rates of 2E1H from floor surface varied with the amount of 2E1H and resin present in the adhesive. When carpet was attached to the flooring material with high water content using adhesive, emission of 2E1H significantly increased. The results show that primary and secondary emissions of 2E1H from the adhesive influence the emission rate of 2E1H for flooring material.  相似文献   
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