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1.
Herein, we report antibacterial and antifungal evaluation of a series of previously prepared (+)-tanikolide analogues. One analogue, (4S,6S)-4-methyltanikolide, displayed promising anti-methicillin-resistant Staphylococcus aureus activity with a MIC of 12.5 µg/mL. Based on the antimicrobial properties of the structurally related (−)-malyngolide, two further analogues (4S,6S)-4-methylmalyngolide and (4R,6S)-4-methylmalyngolide bearing a shortened n-nonyl alkyl side chain were prepared in the present study using a ZrCl4-catalysed deprotection/cyclisation as the key step in their asymmetric synthesis. When these were tested for activity against anti-methicillin-resistant Staphylococcus aureus, the MIC increased to 50 µg/mL.  相似文献   
2.
Sorghum flour was heat treated for producing an instant dispersion ingredient. The precooked sorghum flour was added with ACE-I and DPP-IV inhibitory sorghum peptides (3.0 g peptide 100 g−1). The product was reconstituted in water, and peptide bioaccessibility was evaluated by equilibrium dialysis method after simulated gastrointestinal digestion. Total peptide dialysability of precooked sorghum flour added with sorghum peptides was higher than those obtained for precooked sorghum flour (315.9 ± 14.8 vs. 45.2 ± 5.6 µmol, respectively) (P < 0.05). The ACE-I and DPP-IV-IC50 values of the bioaccessible peptides from the bioactive product were lower than those obtained for precooked sorghum flour ingredient (1.04 ± 0.12 vs. 1.82 ± 0.09 and 0.86 ± 0.02 vs. 2.12 ± 0.08 mg protein mL−1, for ACE-I and DPP-IV, respectively) indicating a higher activity. Precooked sorghum flour was a good vehicle since it did not affect the bioaccessibility of ACE-I and DPP-IV inhibitory peptides provided by sorghum protein hydrolysate.  相似文献   
3.
The effect of pH on colour and iron content (Fe) of peptide fractions obtained from bovine haemoglobin concentrate (BHC) hydrolysates was studied. Four hydrolysates were obtained using three enzymes: Protex‐6‐L (P), Fungal–Protease–Concetrate (FC) and Flavourzyme (F). BHC and its hydrolysates (P, FC, P + F, FC + F) were fractioned at pH 4.5, 7.0 and 9.5. Solubility and Fe from different fractions were measured. Correlations between CIELAB colour parameters and Fe from different fractions were analysed. The colour from different fractions varied from red to yellow (a* and b* positives). Lightness values (L*) ranged from twenty‐four to seventy. FC4.5 and FC + F4.5 fractions were the clearest and yellow (higher L*, b*, h), while BHC9.5 and P + F9.5 fractions had the lowest values of L*, b* and h. There was an inverse linear relationship between b* and L* parameters and Fe from fractions. This relationship could be associated with the pH of extraction. As pH increases Fe significantly increases and lower b* and L* values were obtained.  相似文献   
4.
Laser sources offer a possible solution to the problem of low light throughput in direct-view microscopes (DVMs). However, coherent source DVMs have been shown to suffer from problems such as increased sidelobes in the depth response because of coherent cross talk between neighboring apertures. We explore theoretically how source coherence affects the depth responses of DVMs by employing various aperture spacings and number of apertures. We show that, contrary to expectation, closely spaced apertures can result in decreased full width at half-maximum of the depth response curve. We explain this as an effect of destructive interference when cross talk between neighboring apertures occurs. Using apertures arranged in a square grid as an example, we move on to show that the use of aperture arrays that consist of regularly arranged apertures can accentuate the problematic sidelobes of the depth response. We show that arranging pinholes in a rectangular grid rather than a square grid can improve the optical sectioning strength significantly. Finally, by examination of the depth responses corresponding to the infinite-pinhole-array limit, we make some general statements about source coherence and the characteristics of arrays that are likely to perform well.  相似文献   
5.
根据三峡工程永久船闸边坡块体分布,利用块体理论并结合支护情况探讨了三峡工程永久船闸边坡的稳定性,这对相关问题的研究将提供有益的借鉴作用。  相似文献   
6.
Yang L  Taylor CM  Rakovich Y  McCabe EM 《Applied optics》2003,42(28):5693-5700
We experimentally studied the three-dimensional imaging of the microspheres by using confocal and conventional scanning polarization microscopes. Because of the field amplitude averaging effect of the confocal system, the polarization of the detected signals is mainly parallel to the initial polarization. As a result, the signal intensity from the microspheres in the confocal polarization microscope with a crossed analyzer was found to be weaker than that in the conventional system. Based on a vector approach that takes the polarization into account and on the image formations of the two systems, theoretical expressions are given that agree well with the experimental results.  相似文献   
7.
针对高能耗企业生产能耗耦合建模的问题和能源流、物料流、控制流和排放流,四流合一的模型设计理念,设计开发了企业生产与能耗耦合建模软件.依据工厂实际调研需求和面向对象的分层模块化设计方法,首先给出了软件的总体设计框架,然后详细介绍企业生产与能耗耦合建模软件的各个功能模块开发关键技术.  相似文献   
8.
A novel displaying method, two-field driving scheme, was proposed for field sequential color LCDs without color filter. A spatially modulated color backlight provided multi-primary low-resolution optical stimuli, which were then compensated by an LC panel to display detailed colorful images. That is, the manipulation on three (or more) spatial and two temporal degrees of freedom was sufficient to convey full color information. The simulation results showed that the proposed method achieved acceptable color reproduction accuracy, average CIEDE2000 color difference (DeltaE00) < 3. The least number of fields particularly alleviated the demand for fast-response LC modes in sequential-type LCDs. Furthermore, color break-up suppression was observed due to less chrominance difference between the two fields.  相似文献   
9.
Phase equilibria in ZrO2-YO1.5-SiO2 (ZYS) and ZrO2-GdO1.5-SiO2 (ZGS) were experimentally assessed at 1400?°C and 1600?°C as they can offer insight on reactions between thermal barrier coatings (TBCs) based on ZrO2-YO1.5/GdO1.5 and molten silicate deposits in gas turbine engines. Features shared in both systems include the absence of ternary compounds and no ternary solubility in the binary phases. In ZYS however, a quaternary invariant reaction was observed that eliminates the zircon-disilicate equilibrium at higher temperatures. The results suggest no appreciable difference in the reactions between silica and thermal barrier oxides based on ZrO2-YO1.5 or ZrO2-GdO1.5, or environmental barrier coatings based on the corresponding Y/Gd silicates. The phase diagrams derived from these experiments are part of a broader effort to develop thermodynamic databases that can help guide the design of next-generation TBCs.  相似文献   
10.
工作流模型作为工作流技术的基础,近来得到广泛的研究.本文先简要介绍建模工具RRFloDef的三维工作流模型,针对该模型对商务逻辑处理支持不强,提出在流程调用外部应用程序时增进Web Service支持,并给出了详细的设计方案,最后介绍了根据该方案对RRFloDef所作的改进.  相似文献   
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