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1.
Surface properties of fibrous and ground cotton and linen were investigated by inverse gas chromatography (IGC) and the contact angle with different liquids was also measured on fabrics composed of both fibers. Results proved that dispersion component of surface tension (γ s d ) determined by IGC depends not only on the surface energy, but also on several factors influencing the adsorbability of probe molecules on the cellulosic substrates. For cotton samples, the trapping of n-alkanes among waxy molecules in the outer layer of fibers can be presumed. This effect results in larger γ s d for cotton fibers than for linen in spite of the higher wettability of the linen fabrics. Besides the surface energy and trapping effects, the grinding also influences the γ s d values. Specific enthalpy of adsorption (ΔH A ab ) of polar probes could be determined on all linen samples, but only on the ground cotton sample. Lewis acid-base character calculated for linen and ground cotton samples depends on the same effects as the γ s d does. The similar ΔH A ab values of chloroform (acidic) and THF (basic) measured on each of the samples support the conclusion that the surface character is amphoteric, which is also proved by the high ΔH A ab values of the amphoteric ethyl acetate and acetone probes. 相似文献
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Dr. Erika von Winning 《Journal of pest science》1948,21(9):141-142
Ohne Zusammenfassung 相似文献
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Protocol: a highly sensitive RT-PCR method for detection and quantification of microRNAs 总被引:5,自引:0,他引:5
Erika Varkonyi-Gasic Rongmei Wu Marion Wood Eric F Walton Roger P Hellens 《Plant methods》2007,3(1):12
MicroRNAs (miRNAs) are a class of small non-coding RNAs with a critical role in development and environmental responses. Efficient
and reliable detection of miRNAs is an essential step towards understanding their roles in specific cells and tissues. However,
gel-based assays currently used to detect miRNAs are very limited in terms of throughput, sensitivity and specificity. Here
we provide protocols for detection and quantification of miRNAs by RT-PCR. We describe an end-point and real-time looped RT-PCR
procedure and demonstrate detection of miRNAs from as little as 20 pg of plant tissue total RNA and from total RNA isolated
from as little as 0.1 μl of phloem sap. In addition, we have developed an alternative real-time PCR assay that can further
improve specificity when detecting low abundant miRNAs. Using this assay, we have demonstrated that miRNAs are differentially
expressed in the phloem sap and the surrounding vascular tissue. This method enables fast, sensitive and specific miRNA expression
profiling and is suitable for facilitation of high-throughput detection and quantification of miRNA expression. 相似文献
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Ota Erika do Carmo Cardoso Claudia Andrea Lima Inoue Luis Antonio Kioshi Aoki Zanon Ricardo Basso Silva Tarcila Souza de Castro 《Fish physiology and biochemistry》2022,48(3):735-748
Fish Physiology and Biochemistry - The present study was carried out to evaluate the genotoxic potential of nutritional quality of feed, using erythrocytic nuclear abnormalities assay in Nile... 相似文献
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Erika Moutinho Costa Tatiana Xavier de CastroFernanda de Oliveira Bottino Rita de Cássia Nasser Cubel Garcia 《Veterinary microbiology》2014
To characterize canine coronavirus (CCoV) circulating in diarrheic puppies in Brazil, 250 fecal samples collected between 2006 and 2012 were tested. By using RT-PCR to partially amplify the M gene, CCoV RNA was detected in 30 samples. Sequence analysis of the M protein grouped eight strains with CCoV-I and another 19 with CCoV-II prototypes. To genotype/subtype the CCoV strains and assess the occurrence of single or multiple CCoV infections, RT-PCR of the S gene was performed, and 25/30 CCoV-positive strains amplified with one or two primer pairs. For 17/25 samples, single infections were detected as follows: six CCoV-I, nine CCoV-IIa and two CCoV-IIb. Eight samples were positive for more than one genotype/subtype as follows: seven CCoV-I/IIa and one CCoV-I/IIb. Sequence analysis revealed that the CCoV-I and IIa strains shared high genetic similarity to each other and to the prototypes. The Brazilian strains of CCoV-IIb displayed an aminoacid insertion that was also described in CCoV-IIb-UCD-1 and TGEV strains. Among the 25 CCoV-positive puppies, five had a fatal outcome, all but one of which were cases of mixed infection. The current study is the first reported molecular characterization of CCoV-I, IIa and IIb strains in Brazil. 相似文献
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Reactions of anthocyanins and tannins in model solutions 总被引:1,自引:0,他引:1
Salas E Fulcrand H Meudec E Cheynier V 《Journal of agricultural and food chemistry》2003,51(27):7951-7961
The reaction between procyanidin dimer Ec-EcG (B2 3'-O-gallate) and malvidin 3-O-glucoside (Mv3glc) was studied in a model solution system at two different pH values, 2.0 and 3.8. Disappearance of both species was much faster at pH 3.8 than at pH 2.0. That of Mv3glc was increased in the presence of Ec-EcG, whereas that of Ec-EcG was the same in the presence or absence of the anthocyanin. Values of absorbance at 520 nm measured at pH 2.0 were correlated with the amount of residual Mv3glc. Those measured at pH 3.8 hardly changed during the incubation, but absorbance values at 420 and 620 nm as well as resistance to sulfite bleaching were much increased, confirming that Mv3glc was converted to other pigments. Anthocyanin-flavanol adducts were observed at both pH values, but their structures were different. At pH 2.0, cleavage of the procyanidin linkage followed by nucleophilic addition of flavanol or anthocyanin moieties led to (Ec)(n)-EcG and (Ec)(n)-Mv3glc, respectively. At pH 3.8, nucleophilic addition of Ec-EcG onto the anthocyanin yielded Mv3glc-(Ec-EcG). 相似文献