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.     

Experimental and numerical study on instability structure of the supersonic mixing layer (Mc = 0.5)

The parameters of instability wave of supersonic mixing layer(Mc=0.5,M1=3.5/M2=1.4) are measured by flow visualization and calculated by means of two-dimensional direct numerical simulaitons of the compressible Navier-Stokes equations.In both cases of the mixing layer with harmonic disturbance or not,the comparative results indicate that the wavelength of the two-dimensional wave is equal to the vortex spacing in the streamwise direction because the difference between them is less than 1%.However,the measur...     

应用布儒斯特定律测定玻璃的折射率

介绍应用布儒斯特定律测定玻璃折射率的原理、方法和步骤。     

Preparation, thermo-optic property and simulation of optical switch based on azo benzothiazole polymer

An azo chromophore molecule 4-[(benzothiazole-2-yl)diazenyl]phenyl-1,3-diamine (BTPD) was prepared with 2-amino benzothiazole and m-phenylenediamine by diazo-coupling reaction. Then, the chromophore molecule BTPD was polymerized with NJ-210 and isophorone diisocyanate (IPDI) to obtain novel azo benzothiazole polymer (BTPU). The structures of BTPD and BTPU were characterized using the Fourier transform infrared, UV–visible spectroscopy, DSC and TGA. The physical properties of the obtained BTPU were investigated. The refractive index (n) of BTPU was demonstrated at different temperature and wavelength (532, 650 and 850 nm) using attenuated total reflection technique. The transmission loss and dispersion characteristic of BTPU film were investigated using the CCD digital imaging devices and Sellmeyer equation. A Y-branch and 2 × 2 Mach–Zehnder interferometer (MZI) polymeric thermo-optic switches based on the thermo-optic effect of prepared BTPU were proposed and the performance of switches was simulated. The results indicated that the power consumption of the Y-branch thermo-optic switch could be only 0.6 mW. The Y-branch and MZI switching rising and falling times obtained were 8.0 and 1.8 ms.     

Fault Diagnosis of Rolling Bearings Based on WPE by Wavelet Decomposition and ELM

The fault diagnosis classification method based on wavelet decomposition and weighted permutation entropy (WPE) by the extreme learning machine (ELM) is proposed to address the complexity and non-smoothness of rolling bearing vibration signals. The wavelet decomposition based on ‘db3’ is used to decompose the signal into four layers and extract the approximate and detailed components, respectively. Then, the WPE values of the approximate (CA) and detailed (CD) components of each layer are calculated and composed to be the feature vectors, which are finally fed into the extreme learning machine with optimal parameters for classification. The comparative study of the simulations based on WPE and permutation entropy (PE) shows that the classification method of seven kinds of signals of normal bearing signals and six types of fault states (7 mils and 14 mils) based on WPE (CA, CD) with the number of nodes in the hidden layers of ELM determined by the five-fold cross-validation has the best performances, the training accuracy can reach 100%, and the testing accuracy can reach 98.57% with 37 nodes of the hidden layer by ELM. The proposed method using WPE (CA, CD) by ELM provides guidance for the multi-classification of normal bearing signals.     

百kV级纳秒脉冲源的设计与实验研究

GW级Tesla型脉冲源在触发开关技术研究中作为触发脉冲源使用,抖动较大,触发开关工作不稳定,需要为其研制一台触发器以解决这一问题。结合其他使用需求,设计了一台百kV级纳秒脉冲源,该脉冲源采用Tesla变压器结合单筒脉冲形成线结构,进行了Tesla变压器结构、Tesla变压器初次级参数、Tesla开路磁芯与初级电路设计,调试结果为：最高输出电压100 kV,峰值功率250 MW,重复频率1~100 Hz,输出脉冲宽度约4 ns,前沿约1 ns。该脉冲源作为触发器使用,可以将GW级Tesla型纳秒脉冲源抖动由500 ns降低至150 ns,满足触发开关研究需求,还可用于产生超宽谱短脉冲进行辐射。     

第4代航天育种白芷的FTIR分析

针对植物航天育种变异大的特点,利用傅里叶变换红外光谱(FTIR)结合二阶导数谱对第4代航天育种白芷与地面组白芷从整体上对主要组分进行测定和对比分析。结果表明:太空白芷主要活性成分香豆素类组分(1 741cm-1)含量增加,蛋白质(1 459,1 419cm-1)和脂肪(930cm-1)组分含量略有增加;而淀粉、膳食纤维(1 152,1 105,1 080,1 050cm-1)的含量大幅度降低。二阶导数谱中峰强差异更明显,1 279cm-1处揭示出太空白芷含有胺类组分。航天育种有利于选育出变异幅度大的特异质白芷新品种。     

Mechanism of nickel extraction from sulfuric acid medium by synthesized α‐aminophosphonate derivative

A new compound, α‐aminophosphonate derivative containing pyridine ring (PPDE), was designed and synthesized as an extractant for the separation of nickel from metal impurities. Over 94.5% of Ni (II) extraction from sulfuric acid solution was achieved by using PPDE with an equilibrium pH of 4.02. Meanwhile, high separation coefficients of 23.8 for Ni to Co, 84.9 for Ni to Mn, 254.1 for Ni to Ca and 696.7 for Ni to Mg, respectively, were obtained. It was noted that PPDE exhibited an excellent regenerability, and the extraction of Ni with the recycled organic phase ranged from 92.5% to 93.9% during six circulations. The extracted nickel complex was determined as [Ni (PPDE)₂(DNNSA^?)₂(H₂O)₄], which was supported by the data obtained from Fourier transform‐infrared, UV–Vis and electrospray ionization‐mass spectrometry spectra.     

Development,validation and application of a UHPLC–MS/MS method for quantification of the adiponectin-derived active peptide ADP355 in rat plasma

A UHPLC–MS/MS method for the quantification of ADP355, an adiponectin-derived active peptide, was developed and validated. The extraction method employed simple protein precipitation using methanol and chromatographic separation was achieved on anAccucore™ RP-MS C₁₈ column (100 × 2.1 mm, 2.6 μm, 80 Å), using 0.1% formic acid in both water and acetonitrile with gradient elution at the flow rate of 400 μl/min within 4.0 min. Detections were performed under positive ion mode with multiple reaction monitoring ion transitions m/z 1109.2 → 309.8 and 871.4 → 310.1 for ADP355 and Jt003 respectively at unit resolution. The linearity range of the calibration curve was 2–1,000 ng/ml with a lower limit detection of 0.5 ng/ml. The selectivity, linearity, precision, accuracy, recovery, matrix effect and stability were validated, and all items met the requirement of US Food and Drug Administration guidance. This method was successfully applied to an intravenous pharmacokinetic study of ADP355 in rats and the in-vitro stability in rat serum, plasma and whole blood was also assessed.     

Preparation of novel antimicrobial-modified starch and its adsorption on cellulose fibers: Part I. Optimization of synthetic conditions and antimicrobial activities

Antimicrobial-modified starch was synthesized by covalently bonding guanidine polymer (PHGH) with potato starch via coupling reaction. Orthogonal tests were applied to optimize the reaction conditions. The coupling efficiency could reach 90.21% at the optimal conditions: temperature, 70 °C; time, 2 h; PHGH/starch, 120 wt.%; GDE/starch, 8 wt.%; pH, 11. PHGH modified starches exhibited high antimicrobial activities against both E. coli and S. aureus. Shaking flask method was more suitable for current non-released modified starches than diffusion method to evaluate the antimicrobial activities. In the presence of 1.0 wt.% PHGH in wood fibers, the growth inhibition reached almost 100%. The AFM results also demonstrated that the antimicrobial mechanism of PHGH was to destroy the membrane of the cells.