荧光偏振免疫分析检测粮食及其制品中的真菌毒素研究进展

及时、快速和准确地检测粮食中真菌毒素的污染,从而对其进行严格、科学的控制和处理是保障中国粮食安全和人民身体健康的重要途径。基于特异性分子识别的均相荧光偏振免疫分析技术（Fluorescence Polarization Immunoassay,FPIA）兼具高通量、高速度、高灵敏和易于实现自动化等优点,特别适用于大批量粮食样本的快速筛选。文章综述了近10年来荧光偏振免疫分析检测粮食中真菌毒素的研究进展,并着重讨论了荧光偏振免疫分析的发展方向。     

林木种子介电分选机理的探讨

该文分析了林木种子的介电分选机理,提出了种子理想介质模型,讨论了种子在电场中的极化过程和运动状态,并建立了种子介电分选的数学模型．分析了极化力的形成机制并进行了计算,讨论了影响极化力大小的主要因素．在所建数学模型的基础上,对分选参数作了细致讨论,最终指明这些参数在种子介电分选中的影响     

Nicotine aggravates experimental choroidal neovascularization by modulating macrophage polarization

AIM: To investigate the role of macrophages in the process of nicotine aggravating choroidal neovascularization (CNV). METHODS: After administration of nicotine (100 mg/L in drinking water) for 4 weeks, the mice were used to induce CNV by laser photocoagulation. Seven days after laser injury, the mice were perfused with fluorescein isothiocyanate-labeled dextran through the left ventricle, and areas of CNV were measured. At the 1st, 3rd, 7th and 14th days after laser injury, the spatial and temporal distribution of macrophages was detected by immunofluorescence staining. The mRNA expression of macrophage-related markers were detected by RT-qPCR. Moreover, vascular endothelial growth factor (VEGF) and inflammation-related molecules including intercellular adhesion molecule (ICAM)-1, tumor necrosis factor (TNF)-α and interleukin (IL)-6 in the retinal pigment epithelium-choroid-sclera complexes were detected at the 1st and 3rd days after laser photocoagulation. RESULTS: The degree of leakage and areas of CNV were significantly increased by nicotine exposure compared with control group. Heavy leakage rate and areas of CNV of in nicotine group were 56.25% and (17 569.96±1 444.00) μm², while those in control group were 31.25% and (10 158.63±711.00) μm² (P < 0.05). Nicotine promoted the infiltration of M2 macrophages and increased the ratio of M2/M1 macrophages (P < 0.05). In addition, nicotine accelerated the mRNA expression of M2 macrophage-related markers and up-regulated protein expression of VEGF, ICAM-1, TNF-α and IL-6 (P < 0.05). CONCLUSION: Nicotine promotes the polarization of M2 macrophages, increases the ratio of M2/M1 macrophages, and ultimately accelerates the development of CNV.     

Aberrant SYK expression in cholangiocarcinoma and its effect on M2 macrophage polarization in tumor microenvironment

AIM To investigate the expression of spleen tyrosine kinase (SYK) in 2 murine cholangiocarcinoma (CCA) progressive models and human CCA tissues, and to explore the effects of SYK expression on the polarization of M2 macrophages. METHODS SD rats were given drinking water containing thioacetamide (TAA) daily. BALB/c mice were treated with left median bile duct ligation combined with diethylnitrosamine (DEN) administration. The expression of SYK and M2 macrophage infiltration (CD163) in the animals and human CCA tissues were detected by immunohistochem?istry, and their correlation was analyzed. Ten SD rats, which were given drinking water containing TAA daily for 24 weeks, were randomly divided into control group (n=5) and SYK inhibitor group (n=5). After the rats received SYK inhibitor through gavage for 4 weeks, the effects of SYK inhibitor on tumor growth and macrophage polarization were analyzed. RESULTS The hepatic bile duct hyperplasia, dysplasia (or cholangioma), and CCA occurred at different time points in the rats and mice. During the development of CCA, SYK expression was gradually increased (P<0.01), accompanied by enhanced infiltration of M2 macrophages, while the M1 macrophages were decreased in the hepatic bile duct tissues (P<0.01). SYK and CD163 expression levels were significantly up-regulated (P<0.01), and a positive correlation (r=0.57, P<0.01) in human CCA tissues was observed. In the rat CCA model, the number of tumor nodules and infiltration of M2 macrophages in SYK inhibitor group were decreased compared with its control group (P<0.01). CONCLUSION In the murine CCA models, SYK expression was progressively increased during the evolution of CCA, which may promote tumor progression via the polarization of M2 macrophages, and SYK inhibitor effectively inhibits the tumor growth and M2 macrophage polarization in the rat CCA model.     

猪舍细颗粒物促进猪原代肺泡巨噬细胞向M1极化

旨在研究猪舍细颗粒物（PM_2.5）对猪原代肺泡巨噬细胞（PAMs）精氨酸代谢、炎症因子表达和极化标志物表达的影响。利用支气管肺泡灌洗方法,体外分离PAMs,细胞纯化后,利用Diff-quik染色和F4/80标记鉴定PAMs,并测定细胞活力。将纯化培养的PAMs分为对照组和PM_2.5处理组（50 μg·mL^-1）,继续培养4、8和12 h,测定细胞活力,收集细胞上清测定一氧化氮（NO）的含量,裂解PAMs测定精氨酸酶的活性,并采用RT-PCR检测PAMs炎症因子IL-1β、TNF-α和IL-10以及M1、M2型巨噬细胞标志物CD80和CD206的表达水平。结果显示,通过支气管肺泡灌洗方法成功分离培养了PAMs,并发现PAMs的细胞活力随着培养时间的延长逐渐降低（P<0.05）。PM_2.5处理PAMs,显著提高了细胞上清中NO含量（P<0.05）,显著降低了细胞精氨酸酶的活性（P<0.01）,并显著提高了细胞炎症因子IL-1β和TNF-α mRNA表达水平（P<0.01）,降低了IL-10 mRNA表达水平（P<0.05）。另外,PM_2.5处理PAMs早期,显著提高了CD80 mRNA表达水平（P<0.01）,在后期显著降低CD206 mRNA表达水平（P<0.01）。综上表明,猪舍PM_2.5促进了PAMs向M1表型极化,促进了炎症的发展。     

基于SPAN与NDVI的全极化SAR数据喀斯特地区土地类型划分

地貌复杂性、地物多样性等特征使得全极化SAR（Synthetic Aperture Radar，SAR）数据的散射机制和散射强度相互交织，从而导致基于传统Wishart-H/α的全极化SAR数据难以实现喀斯特地区土地类型的有效划分。针对此问题，本文先用复Wishart距离测度对研究区土地类型样本进行聚类，同时利用H/α平面对研究区进行超盒聚类，然后根据超盒聚类结果平均相干矩阵与样本聚类结果平均相干矩阵间的复Wishart距离进行半监督分类，获得研究区土地类型划分的初步结果。在此基础上利用对建筑物与裸岩地敏感的极化总功率（Polarimetric-Total-Power，SPAN）和对林地、草地与耕地敏感的归一化植被指数（Normalized Differential Vegetation Index，NDVI）对初步结果继续进行划分，最终将研究区土地类型划分为水体、林地、草地、耕地、建筑地和裸岩地，总体分类精度为81.45%；采用另一地势相对平缓、地形相对单一的典型喀斯特地区全极化SAR数据进行验证，在实现该地区土地类型划分的同时总体分类精度为85.66%。说明gai该研究方法能够实现喀斯特地区土地类型的准确划分。     

水分子对无机离子位移极化作用研究

本文讨论了水分子对离子的位移极化作用，计算了极化率大而极化能力小的离子（Ｋ＋，Ｒｂ＋，Ｃｓ＋，Ｆ－，Ｃｌ－，Ｂｒ－，Ｉ－Ｃａ２＋，Ｓｒ２＋，Ｂａ２＋）极化能及其水化热。结果表明，理论计算值与文献值非常相符，最大误差８．７％，表明所得模型与实际情况一致，处理方法可靠     

Spectroscopic Characterization of Fulvic Acid Under Different Cover Crop Systems

Abstract

Fulvic acids (FAs) are an important dynamic component of soils that may be affected by soil management. Carbon‐13 cross‐polarization total sideband suppression nuclear magnetic resonance (CP‐TOSS ¹³C NMR) was used to examine the effect of cover crop systems on the characteristics of fulvic acid fractions. FA was isolated from soils with the following treatments: 1) vetch/rye, 2) rye alone, and 3) check (no cover crops) with varying nitrogen fertilizers. Preliminary NMR results indicate that FA from the rye alone system both with and without nitrogen fertilizers contains less aliphatic carbon (0–108 ppm) than that from the other two treatments. Based on the elemental composition analysis result, C∶N ratio of FA from rye alone cover with or without nitrogen fertilizer is lower than FA from vetch/rye cover system. These data suggest that farming systems affect the FA compositions.     

油田掺水集油系统的高频防垢

对于大庆油田生产的高含蜡、高粘度、高凝固点的石蜡基原油，采用双管掺水集油。为解决掺水造成的水质污染与结垢，从８０年代开始采用化学投药进行阻垢，虽阻垢效率达９０％以上，但因费用高、在９０℃热水中有降解作用、腐蚀管道、污染环境、加药工艺复杂，且只能防垢不能清垢，所以也不是理想的方法。基于以上原因，提出一种新的高频防垢技术，其防垢机理是当掺水介质进入高频电场后，与高频电磁波发生极化作用和空化作用，极化作