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1.
YAN Mingyan LI Bafang ZHAO Xue College of Food Science Engineering Ocean University of China Qingdao P. R. China 《中国海洋大学学报(英文版)》2009,(2)
Collagen of squid(Ommastrephes bartrami) skin was examined in the present study. Histology showed that collagen fiber in the skin was partially cross-linked with muscle fiber. Acid-solubilized collagen(ASC) and pepsin-solubilized collagen(PSC) were extracted from the skin and characterized. The results of amino acid composition and electrophoretic patterns revealed that ASC and PSC were both type Ⅰ collagen,containing α1 and α2 chains. FTIR(fourier transform infrared spectroscopy) investigations confirmed t... 相似文献
2.
N.BRATCHELL 《地理学报(英文版)》1989,(3)
Analysis of multivariate response data by modelling the principal components of the response has beenapplied to two sets of data. In both cases principal components analysis revealed the relationships amongthe response variables and exploited them to simplify the problem of modelling and optimizing themultivariate response. The models and optima obtained from the principal components comparedfavourably with the individual models and simultaneous optima. 相似文献
3.
In this study,we evaluated the anti-proliferative activity of phlorotannins derived from brown algae Laminaria japonica Aresch extracts on the human hepatocellular carcinoma cell (BEL-7402) and on murine leukemic cells (P388) by MTT assay.Cells were incubated with 100 μg/mL of the phlorotannin extract (PE) for 48 h.The inhibitory rate of PE on BEL-7402 and P388 cells was 30.20±1.16% and 43.44±1.86%,respectively,and the half-inhibitory concentration of PE (IC50) on P388 and BEL-7402 cells was 120 μg/mL and >... 相似文献
4.
A ROBUST PLS PROCEDURE 总被引：1，自引：0，他引：1
A robust partial least squares(PLS)regression algorithm is developed.This is achieved by substitutionof the univariate regression steps in the iterative PLS2 algorithm by a robust alternative.The anglebetween loading vectors from both perturbed and unperturbed solutions is used as a measure ofrobustness.By means of a perturbation study on a structure-activity data set,it is demonstrated thatthe stability of the robust method is superior to standard PLS. 相似文献
5.
When the number of variables exceeds the number of samples, one method of multivariate discriminationis to use principal components analysis to reduce the dimensionality and then to perform canonicalvariates analysis (PC-CVA). This paper proposes an alternative approach in which discriminant analysisis carried out by a weighted principal component analysis of the group means (DPCA). This method doesnot require prior data reduction and produces discriminant factors that are orthogonal in the original dataspace. The theory and performance of the two methods are compared. Although the individual factors ofDPCA are found to be less discriminating than PC-CVA, the overall discrimination, calculated bymultivariate analysis of variance, and the predictive value, estimated by the leaving-one-out error rate,are broadly comparable. 相似文献
6.
For the investigation of anti-infection immune response of Pseudosciaena crocea, 160 healthy fish samples were categorized into infected and control groups. Each individual fish in the infected group was injected intraperitoneally (i.p.) with 0.2 ml bacterial suspension of Vibrio alginolyticus in density of 2×107 CFU/ml, while each individual in the control group was injected i.p. with 0.2 ml sterile saline solution (0.85%). It was observed that the artificial injection of V. alginolyticus significantly inc... 相似文献
7.
A TEST OF SIGNIFICANCE FOR PARTIAL LEAST SQUARES REGRESSION 总被引：1，自引：0，他引：1
IAN N. WAKELING JEFF J. MORRIS AFRC Institute of Food Research Earley Gate Whiteknights Ro Reading RG EF U.K.Zeneca Pharmaceuticals Mereside Alderley Park Macclesfiel Cheshire SK TG U.K. 《地理学报(英文版)》1993,(4)
Partial least squares (PLS) regression is a commonly used statistical technique for performingmultivariate calibration, especially in situations where there are more variables than samples. Choosingthe number of factors to include in a model is a decision that all users of PLS must make, but iscomplicated by the large number of empirical tests available. In most instances predictive ability is themost desired property of a PLS model and so interest has centred on making this choice based on aninternal validation process. A popular approach is the calculation of a cross-validated r~2 to gauge howmuch variance in the dependent variable can be explained from leave-one-out predictions. Using MonteCarlo simulations for different sizes of data set, the influence of chance effects on the cross-validationprocess is investigated. The results are presented as tables of critical values which are compared againstthe values of cross-validated r~2 obtained from the user's own data set. This gives a formal test forpredictive ability of a PLS model with a given number of dimensions. 相似文献
8.
Coccolithophorid is unicellular marine microalgae with a global distribution in temperate and sub-temperate oceanic regions and has the ability to produce ‘the coccoliths'. It is considered to be the second most productive calcifying organism on earth and becoming an important factor in the global carbonate cycle. Emiliania huxleyi is one of the only two bloom-forming coccolithophores and becomes a species crucial to the study of global biogeochemical cycles and climate modeling. Coccolithoviruse is a recently discovered group of viruses infecting the marine coccolithophorid E. huxleyi. They are a major cause of coccolithophore bloom termination, and DMSP concentration is increasing in the process of viral lysis. Phylogenetic evidences support that some genes are functional both in E. huxleyi and its virus(Eh V). Horizontal gene transfer(HGT) of multiple functionally coupled enzymes occurs in E. huxleyi and its DNA virus Eh V has been confirmed, which contributes to the diversification and adaptation of plankton in the oceans and also critically regulates virus-host infection by allowing viruses to control host metabolic pathways for their replication. Therefore, it is of particular interest to understand this host-virus interaction. On this issue, we have made a minireview of coccolithoviruses focusing on the basic characteristics, phylogenesis, horizontal gene transfer and the interaction between the host and its viruses, as well as its important role in global biogeochemical cycling. 相似文献
9.
采用改良微孔板法建立哈维氏弧菌Vibrio harveyi TS-628菌株生物被膜体外模型,并进一步研究环境因子对哈维氏弧菌体外形成生物被膜的影响。结果发现,哈维氏弧菌TS-628菌株可以在聚苯乙烯板中形成生物被膜,并且该菌生物被膜的形成受起始菌液浓度、温度、pH等理化因子的显著影响。温度为30℃、NaCl质量分数为3%—6%、pH为7、孵育时间为36h是哈维氏弧菌形成生物被膜的最佳条件。此外哈维氏弧菌在分别经表皮黏液、鳃黏液、肠道黏液、肝脏提取液、脾脏提取液、肌肉提取液包被的基质上成膜效果显著,其中在经肝脏提取液包被的基质上形成的生物被膜量显著高于在其他生物基质上形成的生物被膜量(p<0.01)。 相似文献
10.
The theory of experimental error in analysis of mixture experiments by abstract factor analysis or targettransformation factor analysis is considered. The theoretical implications of using signal-to-noise ratios(as weights) or canonical variates analysis to reduce the level of imbedded error in the factor model areexamined. The approach is illustrated by application to ~(13)C NMR spectra of lubricant basestockmixtures. 相似文献