Bioinspired Healable Mechanochromic Function from Fluorescent Polyurethane Composite Film

Camouflage and wound healing are two vital functions for cephalopods to survive from dangerous ocean risks. Inspired by these dual functions, herein, we report a new type of healable mechanochromic (HMC) material. The bifunctional HMC material consists of two tightly bonded layers. One layer is composed of polyvinyl alcohol (PVA) and titanium dioxide (TiO₂) for shielding. Another layer contains supramolecular hydrogen bonding polymers and fluorochromes for healing. The as-synthesized HMC material exhibits a tunable and reversible mechanochromic function due to the strain-induced surface structure of composite film. The mechanochromic function can be further restored after damage because of the incorporated healable polyurethane. The healing efficiency of the damaged HMC materials can even reach 98 % at 60 °C for 6 h. The bioinspired HMC material is expected to have potential applications in the information encryption and flexible displays.     

利用反射太赫兹时域强度分布定量检测沙粒中的微量原油

原油污染是海洋生物和环境安全的主要威胁之一,检测近海沙粒中的微量原油对于环境保护和原油勘探有着重要意义.本文采用反射式太赫兹时域波形对近海沙粒中的原油进行定量检测,详细地分析了延迟时间与沙粒中的原油浓度的关系.结果表明,原油浓度与延迟时间呈线性递减关系,反射式太赫兹时域波形是一种具有潜力的污染定量检测方法.     

The metabolites and biotransformation pathways in vivo after oral administration of ocotillol,RT5, and PF11

Ocotillol, pseudo-ginsenoside RT5 (RT₅), and pseudo-ginsenoside F₁₁ (PF₁₁) are ocotillol-type saponins that have the same aglycone structure but with different numbers of glucose at the C-6 position. In this study, the metabolites of ocotillol, RT₅, and PF₁₁ in rat plasma, stomach, intestine, urine, and feces after oral administration were investigated by ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry. The results showed that RT₅ was easily biotransformed into metabolites in vivo, whereas PF₁₁ and RT₅ were difficult to be biotransformed. Hydrogenation, dehydrogenation, dehydration, deglycosylation, deoxygenation, hydration, phosphorylation, deoxidation, glucuronidation, and reactions combining amino acid were speculated to be involved in the biotransformation of ocotillol, RT₅, and PF₁₁. Based on the structural analysis of metabolites, it was deduced that hydrogenation, dehydration, deoxidation, and reactions combining amino acid occurred on the aglycone structure, whereas deglycosylation, hydration, and phosphorylation occurred on the glycosyl chain. Further, metabolites in plasma, urine, feces, and tissues were different: First, glucuronidation products were found in urine, stomach, intestine, and feces, but not in plasma. Second, the ocotillol prototype was not identified in urine samples. Third, the RT₅ prototype was found in stomach, intestine, feces, and urine, but not in plasma.     

Spleen and thymus metabolomics strategy to explore the immunoregulatory mechanism of total withanolides from the leaves of Datura metel L. on imiquimod-induced psoriatic skin dermatitis in mice

Our previous work demonstrated that total withanolides of Datura metel L. leaves (TWD) exhibited excellent therapeutic effects on psoriasis. However, current knowledge of its mechanisms is incomplete. In this study, integrated spleen and thymus untargeted metabolomics were used to analyze the changes in endogenous metabolites underlying the immunosuppressive activity of TWD on psoriasis animal models induced by imiquimod. The results suggested that TWD treatment markedly attenuated imiquimod-induced psoriasis and showed significant immunosuppressive activity as evidenced by decreased elevation index of spleen and thymus. Meanwhile, TWD significantly reversed the elevation of immunoregulatory factors, including IL-10, IL-17, IL-22 and IL-23. Multivariate trajectory analysis revealed that TWD treatment could restore the psoriasis-disturbed spleen and thymus metabolite profiles towards the normal metabolic status. A total of 25 and 27 metabolites associated with the immunomodulatory effects for which levels changed markedly upon treatment have been identified in spleen and thymus, respectively. These differential metabolites were mainly involved in amino acid metabolism, nucleotide metabolism, fatty acid metabolism and lipid metabolism. Our investigation provided a holistic view of TWD for intervention in psoriasis through immunoregulation and provided further scientific information in vivo about a clinical value of TWD for psoriasis.     

新型共价交联纳米胶囊的构筑、调控与功能

利用共价自组装的方法，将刚性组装基元与柔性链在一定条件下进行横向交联，可以方便地制备出单层高分子纳米胶囊.相比于传统的非共价超分子囊泡，这种新型的共价纳米胶囊具有结构稳定、尺度可控且分散性优异等诸多优点.因此，如何利用化学合成的手段来制备新型的纳米胶囊，并进一步实现对其结构调控和性能的探究具有十分重要的意义.针对这些问题，分别发展了功能化的柱[5]芳烃、四苯乙烯、卟啉、三嗪、苯硼酸酐等不同类型构筑基元，并使之与两端具有活性位点的柔性烷基链在适当的溶剂中进行聚合反应，最终获得了一系列的共价纳米胶囊.通过对其结构的修饰和调控，发现这些功能化的高分子纳米胶囊在光捕获、人工酶、抗菌材料以及药物载体等领域具有诸多潜在应用价值.未来，新型共价高分子纳米胶囊的开发、功能化以及应用有望得到进一步的拓展.     

基于微腔效应增强单层二硫化钨光吸收

提出基于金属薄膜-分布式布拉格反射器微腔效应增强单层二硫化钨光吸收的多层薄膜结构.运用光学传输矩阵理论研究了其输运特性,发现由于金属薄膜-分布式布拉格反射器的微腔效应,在间隔层和覆盖层之间形成电场强度极大值,有效促进入射光与单层二硫化钨的相互作用.综合优化金属层、间隔层和覆盖层厚度,单层二硫化钨在612 nm处的光吸收提高了38倍,达到78.42;.进一步探讨了光入射角、分布式布拉格反射器周期、间隔层折射率与单层二硫化钨光吸收的关系.研究结果表明,上述结构参数的变化可有效调控单层二硫化钨的吸收峰值.研究结果为制备高性能单层二硫化钨光电探测器等新型光电子器件提供了新思路.     

平板几何迁移算子的特征值问题

研究L^p(1相似文献   

The antidepressant effect of 4-hydroxybenzyl alcohol 2-naphthoate through monoaminergic,GABAergic system and BDNF signaling pathway

Abstract

Gastrodigenin, also known as 4-hydroxybenzyl alcohol (HBA), is one of the main components of Gastrodia elata, which is a perfect lead compound of natural products. In order to get new active compounds, we modified the structure of HBA through esterification with carboxylic acid, and got a series of derivatives in which 4-hydroxybenzyl alcohol 2-naphthoate (NHBA) showed stronger antidepressant activity than HBA. In this paper, we firstly evaluated the antidepressant activity of NHBA by tail suspension test (TST) and forced swimming test (FST). Then, we carried out the biochemical assay and western blot to determine its mechanism. The results displayed that NHBA could increase the content of serotonin, dopamine, norepinephrine, γ-aminobutyric acid, brain-derived neurotrophic factor (BDNF) and tropomyosin receptor kinase B (TrkB) in mice brain. It suggested that NHBA exhibited an antidepressant-like effect through monoaminergic system, GABAergic system and BDNF/TrkB signaling pathways.