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31.
Soyasaponins and isoflavones are main secondary metabolites in soybeans. In this report we compared the content of secondary metabolites between genetically modified (GM) and non-GM soybeans. Six cultivars/lines of GM and six cultivars/lines of non-GM soybeans were extracted with methanol. Each extract was partitioned with aqueous methanol and hexane and the aqueous methanol fraction was partially purified by HP-20 and LH-20 column chromatography to afford crude soyasaponin and isoflavone fractions. The main A-type soyasaponin, acetylsoyasaponin A1 (AcA1), and the main B-type soyasaponins, soyasaponins I and II (I and II), in the crude fractions were identified by LC/MS analyses with authentic samples. The main isoflavones, daidzin, genistin, daidzein and genistein (DI, GI, DE and GE), in the crude fractions were identified by LC photo-diode array analyses with authentic samples. The contents of AcA1, I and II in the crude soyasaponin fractions and those of DI, GI, DE and GE in the crude isoflavone fractions were analyzed by reversed-phase HPLC. The average contents (mg/100 g) of AcA1, I, II and total of B-type soyasaponins in GM soybeans were 36.4 +/- 24.2, 51.2 +/- 11.8, 26.4 +/- 7.6 and 77.7 +/- 18.5, respectively, and those in non-GM ones were 22.3 +/- 14.7, 46.3 +/- 17.8, 19.8 +/- 9.1 and 65.9 +/- 26.9, respectively. The average contents (mg/100 g) of DI, GI, DE, GE and total isoflavones in GM soybeans were 93.1 +/- 15.5, 121.8 +/- 19.4, 0.073 +/- 0.178, 0.320 +/- 0.082 and 215.3 +/- 33.3, respectively, and those in non-GM ones were 78.8 +/- 34.6, 106.7 +/- 28.3, 2.206 +/- 4.468, 0.822 +/- 0.754 and 188.5 +/- 26.7, respectively. There were no statistically significant differences in soyasaponin and isoflavone contents between GM and non-GM soybeans. Therefore, it was estimated that the GM soybeans are equivalent to the non-GM ones in terms of the composition of the main secondary metabolites.  相似文献   
32.
A new wavelength interval selection procedure, moving window partial least-squares regression (MWPLSR), is proposed for multicomponent spectral analysis. This procedure builds a series of PLS models in a window that moves over the whole spectral region and then locates useful spectral intervals in terms of the least complexity of PLS models reaching a desired error level. Based on a proposed theory demonstrating the necessity of wavelength selection, it is shown that MWPLSR provides a viable approach to eliminate the extra variability generated by non-composition-related factors such as the perturbations in experimental conditions and physical properties of samples. A salient advantage of MWPLSR is that the calibration model is very stable against the interference from non-composition-related factors. Moreover, the selection of spectral intervals in terms of the least model complexity enables the reduction of the size of a calibration sample set in calibration modeling. Two strategies are suggested for coupling the MWPLSR procedure with PLS for multicomponent spectral analysis: One is the inclusion of all selected intervals to develop a PLS calibration model, and the other is the combination of the PLS models built separately in each interval. The combination of multiple PLS models offers a novel potential tool for improving the performance of individual models. The proposed procedures are evaluated using two open-path Fourier transform infrared data sets and one near-infrared data set, each having different noise characteristics. The results reveal that the proposed procedures are very promising for vibrational spectroscopy-based multicomponent analyses and give much better prediction than the full-spectrum PLS modeling.  相似文献   
33.
Abstract— A full‐color AMOLED display with an RGBW color filter pattern has been fabricated. Displays with this format require about one‐half the power of analogous RGB displays. RGBW and RGB 2.16‐in.‐diagonal displays with average power consumptions of 180 and 340 mW, respectively, were characterized for a set of standard digital still camera images at a luminance of 100 cd/m2. In both cases, a white‐emitting AMOLED was used as the light source, and standard LCD filters were used to provide the R, G, and B emission. The color gamuts of these displays were identical and the higher overall efficiency of the RGBW format results from two factors. First, a large fraction of a typical image is near neutral in color and can be reproduced using the white sub‐pixel. Second, the white sub‐pixel in an RGBW AMOLED display is highly efficient because of the absence of any color filter. The efficiency of these displays can be further enhanced by choosing a white emitter optimized to the target display white point (in this case D65). A two‐emission layer configuration based upon separate yellow and blue‐emitting regions is shown to be well suited for both the RGBW and RGB formats.  相似文献   
34.
The influence of the Fermi surface anisotropy on the specific heat jump is studied for the p-wave superconductor with a gap function d = z^(k x ± ik y ) in connection with Sr2RuO4. It is shown that the normalized specific heat jump, C/T c , is reduced from its universal value, 1.43, in accordance with experimental findings. We show that this behavior fits well into our present understanding of the quasiparticle spectrum and the impurity effects.  相似文献   
35.
Periplasmic binding proteins (PBPs) serve as receptors for various water-soluble ligands in ATP-binding cassette (ABC) transport systems, and form one of the largest protein families in eubacterial and archaebacterial genomes. They are considered to be derived from a common ancestor, judging from their similarities of three-dimensional structure, their mechanism of ligand binding and the operon structure of their genes. Nevertheless, there are two types of topological arrangements of the central beta-sheets in their core structures. It follows that there must have been differentiation in the core structure, which we call "domain dislocation", in the course of evolution of the PBP family. To find a clue as to when the domain dislocation occurred, we constructed phylogenetic trees for PBPs based on their amino acid sequences and three-dimensional structures, respectively. The trees show that the proteins of each type clearly cluster together, strongly indicating that the change in the core structure occurred only once in the evolution of PBPs. We also constructed a phylogenetic tree for the ABC proteins that are encoded by the same operon of their partner PBP, and obtained the same result. Based on the phylogenetic relationship and comparison of the topological arrangements of PBPs, we obtained a reasonable genealogical chart of structural changes in the PBP family. The present analysis shows that the unidirectional change of protein evolution is clearly deduced at the level of protein three-dimensional structure rather than the level of amino acid sequence.  相似文献   
36.
Most populations and some species of ticks of the genera Boophilus (5 spp.) and Rhipicephalus (ca. 75 spp.) cannot be distinguished phenotypically. Moreover, there is doubt about the validity of species in these genera. I studied the entire second internal transcribed spacer (ITS 2) rRNA of 16 populations of rhipicephaline ticks to address these problems: Boophilus microplus from Australia, Kenya, South Africa and Brazil (4 populations); Boophilus decoloratus from Kenya; Rhipicephalus appendiculatus from Kenya, Zimbabwe and Zambia (7 populations); Rhipicephalus zambesiensis from Zimbabwe (3 populations); and Rhipicephalus evertsi from Kenya. Each of the 16 populations had a unique ITS 2, but most of the nucleotide variation occurred among species and genera. ITS 2 rRNA can be used to distinguish the populations and species of Boophilus and Rhipicephalus studied here. Little support was found for the hypothesis that B. microplus from Australia and South Africa are different species. ITS 2 appears useful for phylogenetic inference in the Rhipicephalinae because in genetic distance, maximum likelihood, and maximum parsimony analyses, most branches leading to species had >95% bootstrap support. Rhipicephalus appendiculatus and R. zambeziensis are closely related, yet their ITS 2 sequences could be distinguished unambiguously. This lends weight to a previous proposal that Rhipicephcalus sanguineus and Rhipicephalus turanicus, and Rhipicephalus pumilio and Rhipicephalus camicasi, respectively, are conspecific, because each of these pairs of species had identical sequences for ca. 250 bp of ITS 2 rRNA.  相似文献   
37.
In the present study, we attempted to determine the extent to which an anterior capsulorrhexis carried out during cataract surgery contracts postoperatively. The size of the continuous curvilinear capsulorrhexis (CCC) was measured at the end of surgery and at the final follow-up examination in 52 eyes of 40 patients who underwent phacoemulsification/aspiration and implantation of an intraocular lens (IOL) with 6-mm optics. Images obtained by video during surgery and by slit-lamp microscopy were used to determine the CCC size with reference to the optics of the IOL. The average CCC size was 5.0 mm at the end of surgery; it contracted to 4.4 mm by the final postoperative examination. The contraction of the anterior capsule progressed rapidly in the first 50 days following surgery and then gradually thereafter. The extent of contraction was greater in older patients. The smaller the CCC size immediately after surgery, the more rapidly it contracted. The size of the capsulorrhexis contracted an average of 22% following cataract surgery. The contraction rate tended to be higher in older patients. The results suggest that the capsulorrhexis carried out in cataract surgery for elderly patients should be sufficiently large, but not larger than the optics size of the IOL.  相似文献   
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Simple and comprehensive two-dimensional (2D)-HPLC was studied in a reversed-phase mode using monolithic silica columns for second-dimension (2nd-D) separation. Every fraction from the first column, 15 cm long (4.6-mm i.d.), packed with fluoroalkylsilyl-bonded (FR) silica particles, was subjected to the separation in the 2nd-D using one or two octadecylsilylated (C(18)) monolithic silica columns (4.6-mm i.d., 3 cm). Monolithic silica columns in the 2nd-D were eluted at a flow rate of up to 10 mL/min with separation time of 30 s that meets the fractionation every 15-30 s at the first dimension (1st-D) operated at a flow rate of 0.4-0.8 mL/min. Three cases were studied. (1) In the simplest scheme of 2D-HPLC, effluent of the 1st-D was directly loaded into an injector loop of 2nd-D HPLC for 28 s, and 2 s was allowed for injection. (2) Two six-port valves each having a sample loop were used to hold the effluent of the 1st-D alternately for 30 s for one 2nd-D column to effect comprehensive 2D-HPLC without the loss of 1st-D effluent. (3) Two monolithic silica columns were used for 2nd-D by using a switching valve and two sets of 2nd-D chromatographs separating each fraction of the 1st-D effluent with the two 2nd-D columns alternately. In this case, two columns of the same stationary phase (C(18)) or different phases, C(18) and (pentabromobenzyloxy)propylsilyl-bonded (PBB), could be employed at the 2nd-D, although the latter needed two complementary runs. The systems produced peak capacity of approximately 1000 in approximately 60 min in cases 1 and 2 and in approximately 30 min in case 3. The three stationary phases, FR, C(18), and PBB, showed widely different selectivity from each other, making 2D separations possible. The simple and comprehensive 2D-HPLC utilizes the stability and high efficiency at high linear velocities of monolithic silica columns.  相似文献   
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