Discriminant Analysis of the Nutritional Components between Organic Eggs and Conventional Eggs: A 1H NMR-Based Metabolomics Study

The difference of nutrient composition between organic eggs and conventional eggs has always been a concern of people. In this study, ¹H nuclear magnetic resonance (NMR) technique combined with multivariate statistical analyses was conducted to identify the metabolite different in egg yolk and egg white in order to reveal the nutritional components information between organic and conventional eggs. The results showed that the nutrient content and composition characteristics were different between organic and conventional eggs, among which the content of glucose, putrescine, amino acids and their derivatives were found higher in the organic eggs yolk, while phospholipids were demonstrated higher in conventional eggs yolk. Organic acid, alcohol, amine, choline and amino acids were higher in conventional eggs white, but glucose and lactate in organic egg were higher. Our study demonstrated that there are more nutritive components and higher nutritional value in organic eggs than conventional eggs, especially for the growth and development of infants and young children, and conventional eggs have more advantages in promoting lipid metabolism, preventing fatty liver, and reducing serum cholesterol. Eggs have important nutritional value to human body, and these two kinds of eggs can be selected according to the actual nutrient needs.     

Antiinflammation Derived Suzuki-Coupled Fenbufens as COX-2 Inhibitors: Minilibrary Construction and Bioassay

A small fenbufen library comprising 18 compounds was prepared via Suzuki Miyara coupling. The five-step preparations deliver 9–17% biphenyl compounds in total yield. These fenbufen analogs exert insignificant activity against the IL-1 release as well as inhibiting cyclooxygenase 2 considerably. Both the para-amino and para-hydroxy mono substituents display the most substantial COX-2 inhibition, particularly the latter one showing a comparable activity as celecoxib. The most COX-2 selective and bioactive disubstituted compound encompasses one electron-withdrawing methyl and one electron-donating fluoro groups in one arene. COX-2 is selective but not COX-2 to bioactive compounds that contain both two electron-withdrawing groups; disubstituted analogs with both resonance-formable electron-donating dihydroxy groups display high COX-2 activity but inferior COX-2 selectivity. In silico simulation and modeling for three COX-2 active—p-fluoro, p-hydroxy and p-amino—fenbufens show a preferable docking to COX-2 than COX-1. The most stabilization by the p-hydroxy fenbufen with COX-2 predicted by theoretical simulation is consistent with its prominent COX-2 inhibition resulting from experiments.     

基于逐步回归法的近红外光谱信息提取及模型的研究

基于多元线性回归的逐步分析算法 ,依据小麦粉的近红外吸收特性机理 ,对小麦粉的近红外光谱(10 0 0～ 2 5 0 0nm)划分三波段 (Ⅰ :10 0 0～ 14 0 0nm ;Ⅱ :14 0 0～ 186 0nm ;Ⅲ :186 0～ 2 5 0 0nm) ,并进行了各波段的光谱信息提取 ,确定了回归特征波长 ,对不同波段建立的回归模型进行了比较 ,给出了各段回归的最佳数学模型。通过对小麦粉近红外谱的信息提取及蛋白质成分的定量分析 ,比较和讨论了不同波段所建模型对小麦粉蛋白质含量的近红外分析结果 ,在应用中有一定的参考价值。     

Mn（Ⅱ）,Co（Ⅱ）与HSA相互作用的荧光光谱研究

用荧光光谱法研究了生理ｐＨ和等离子点（ｐＨ＝５．３０）时Ｍｎ（Ⅱ）、Ｃｏ（Ⅱ）与ＨＳＡ的相互作用。根据Ｆｏｒｓｔｅ非辐射能量转移理论,得到了不同ｐＨ时Ｍｎ（Ⅱ）、Ｃｏ（Ⅱ）在ＨＳＡ中的第一强结合位置与Ｔｒｐ－２１４残基间的距离。这一结果远大于文献报道值,根据Ｍｎ（Ⅱ）、Ｃｏ（Ⅱ）在ＨＳＡ中的结合部位及ＨＳＡ的畴结构对这一显著差异进行了讨论。     

Versatile Graphene-Isolated AuAg-Nanocrystal for Multiphase Analysis and Multimodal Cellular Raman Imaging

Main observation and conclusion Surface-enhanced Raman spectroscopy(SERS)-based bioanalytical technique involves the interaction of SERS-active substrate with c...     

Semiparametric Bayesian inference for mean-covariance regression models

In this paper, we propose a Bayesian semiparametric mean-covariance regression model with known covariance structures. A mixture model is used to describe the potential non-normal distribution of the regression errors. Moreover, an empirical likelihood adjusted mixture of Dirichlet process model is constructed to produce distributions with given mean and variance constraints. We illustrate through simulation studies that the proposed method provides better estimations in some non-normal cases. We also demonstrate the implementation of our method by analyzing the data set from a sleep deprivation study.     

压力膨化处理对正极性聚丙烯蜂窝膜的驻极体性质的影响

压力膨化处理工艺能够显著改善聚丙烯蜂窝薄膜（cellular polypropylene） 驻极体的压 电活性.通过热脉冲技术、表面电位衰减测量及TSD 电流谱分析等研究了经恒压正电晕充电 的聚丙烯蜂窝膜的陷阱能级分布特征，讨论了压力膨化处理工艺对这类蜂窝膜驻极体电荷稳 定性及电荷输运特性的影响.结果说明，PP 蜂窝膜内存在着位于中能级区的能值各异的三种 分立陷阱，深能值陷阱和浅能值陷阱的大多数位于孔洞膜近表面的体层或体内，而中等能值 陷阱则主要位于自由面附近.压力膨化处理改变了PP 蜂窝膜的能阱状态并在一定程度上降低 了这类孔洞膜驻极体的电荷储存稳定性，但没有明显影响其由慢再俘获效应占主导地位的脱 阱电荷输运特性. 关键词： 压力膨化处理 聚丙烯蜂窝膜 驻极体 电荷储存与陷阱分布 电荷输运     

低温下Er3+/Yb3+共掺碲酸盐玻璃的发光特性研究

研究了在8—300K温度范围中, Er³⁺/Yb³⁺共掺碲酸盐玻璃的15μm荧光光谱、上转换光谱与温度的关系. Er³⁺:⁴I_13/2→⁴I_15/2跃迁发射光谱通过高斯拟合和简单的四能级系统估计了Er³⁺离子⁴I_13/2和⁴ 关键词： 碲酸盐玻璃 上转换发光 低温 荧光特性     

NⅡ离子2p4f—2p3d辐射跃迁概率的理论研究

在全相对论理论框架下，利用多组态Dirac-Fock(MCDF)方法，系统计算了NⅡ离子2p4f—2p3d的辐射跃迁概率，得到的结果与已有实验值符合很好.具体计算中，详细分析了相对论效应、电子关联、弛豫效应、Breit相互作用和量子电动力学(QED)效应对能级精细结构及辐射跃迁概率的影响.结果表明：相对论效应、电子关联和弛豫效应对NⅡ 2p4f-2p3d辐射跃迁概率有很重要的影响,考虑了这些效应后计算值得到明显改善.     

氧气氛低温退火Pt/Ba0.8Sr0.2TiO3Pt引起的低频介电弛豫效应

研究了在不同温度区间氧气氛和氮气氛退火后处理对PtBa0.8Sr0.2TiO3Pt介电特性的影响.经过高温550℃氮气退火处理后,再放入350℃的氧气中退火,发现样品的介电特性出现了非常明显的低频弛豫现象,并且这种低频弛豫现象在350℃的氮气中退火后将会消失.通过在出现低频弛豫现象的样品的上下电极加一偏压,可以发现低频弛豫现象更加明显,并且在撤消偏压后这种增强将会逐渐减弱,直至最终恢复到偏压前的弛豫状态 关键词： 脉冲激光沉积 介电弛豫 动态随机存储器