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101.
Fast compressive tracking utilizes a very sparse measurement matrix to capture the appearance model of targets. Such model performs well when the tracked targets are well defined. However, when the targets are low-grain, low-resolution, or small, a single fixed size sparse measurement matrix is not sufficient enough to preserve the image structure of the target. In this work, we propose a multi-sparse measurement matrices scheme along with a weight map to select the best measurement matrix that preserves the image structure of the targets during tracking. The weight map combines a contrast weight and a feature weight to efficiently characterize the target appearance and location. Moreover, a dispersion function is used for the online update of the target template, allowing tracking both the location and scale of the target. Extensive experimental results have demonstrated that the proposed DWCM tracking algorithm outperforms several state-of-the-art tracking algorithms as well as compressive tracker. 相似文献
102.
Authentication of Polygonati Odorati Rhizoma and other two Chinese Materia Medica of the Liliaceae family by pharmacognosy technique with GC–MS analysis 下载免费PDF全文
Yingjiao Liu Canhuang Liu Yafei Yu Bei Xu Limin Gong Xiaoyan Zeng Lan Xiao Qilai Cheng Tasi Liu 《Microscopy research and technique》2015,78(2):119-127
Yuzhu (Polygonati Odorati Rhizoma), Kangdingyuzhu (Polygonati Prattii Rhizoma), and zhugenqiyuzhu (Disporopsis Fuscopictae Rhizoma) are of the same family, but of different genera. They have all often used in Chinese Materia Medica (CMM) as Polygonati Odorati Rhizoma in China market. Three species of CMM are confused. For better application, we need to identify these plants accurately. This study use pharmacognosy technique and GC‐MS analysis, three species of CMM were authenticated. In macroscopic characteristics, the fruit of Polygonati Odorati Rhizoma is blue‐black, while the other two are maroon and dark purple orderly. Nodes of Polygonati Odorati Rhizoma are upward and light uplift, about 1 cm spacing, while the other are not. As for microscopic characteristics, the cortex of Polygonati Odorati Rhizoma only occupies about 1/5 of the radius of the transverse section with inconspicuous endodermis, which is much smaller than others. The type of vascular bundles of Polygonati Odorati Rhizoma is closed collateral, but the other is amphivasal. Raphides of calcium oxalate are scattered, but Raphides of the other two are like brooms and neat rows. GC–MS analysis of essential oil could provide different characteristics to distinguish three species. Twenty‐three compounds were identified from essential oil of Polygonati Odorati Rhizoma and the main components were n‐hexadecanoic acid (49.45%), while n‐hexadecanoic acid of the other two are 23.92% and 9.45%. The content of n‐hexadecanoic is strongly different. This research was aimed to establish a method by pharmacognosy and GC–MS analysis to identify three CMM and for providing scientifical data to ensure accuracy of origin of three species. Microsc. Res. Tech. 78:119–127, 2015. © 2014 Wiley Periodicals, Inc. 相似文献
103.
Oxidative stress plays important roles in a wide range of diseases such as cancer, inflammatory disease, neurodegenerative disorders, etc. Tyrosine nitration in a protein is a chemically stable oxidative modification, and a marker of oxidative injuries. Mass spectrometry (MS) is a key technique to identify nitrotyrosine‐containing proteins and nitrotyrosine sites in endogenous and synthetic nitroproteins and nitropeptides. However, in vivo nitrotyrosine‐containing proteins occur with extreme low‐abundance to severely challenge the use of MS to identify in vivo nitroproteins and nitrotyrosine sites. A preferential enrichment of nitroproteins and/or nitropeptides is necessary before MS analysis. Current enrichment methods include immuno‐affinity techniques, chemical derivation of the nitro group plus target isolations, followed with tandem mass spectrometry analysis. This article reviews the MS techniques and pertinent before‐MS enrichment techniques for the identification of nitrotyrosine‐containing proteins. This article reviews future trends in the field of nitroproteomics, including quantitative nitroproteomics, systems biological networks of nitroproteins, and structural biology study of tyrosine nitration to completely clarify the biological functions of tyrosine nitration. © 2013 Wiley Periodicals, Inc. Mass Spec Rev 34: 423–448, 2015. 相似文献
104.
Three-dimensional(3 D) graphene oxide-tris(4-aminophenyl)amine(GO-TAPA_(x:y)) composites with different GO-to-TAPA mass ratios(x:y) were prepared by a facile one-step ultrasonic treatment.GOTAPA_(x:y) composites were characterized by scanning electron microscopy(SEM),nitrogen(N2)adsorption-desorption isotherms,Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS) and thermogravimetric analysis(TGA).Behavior and mechanism of GO-TAPA_(x:y)co mposites for the adsorption of rare earth elements(REEs) were investigated.The adso rption capacities of GO-TAPA_(1;2) composite for Yb~(3+),Er~(3+),Nd~(3+),La~(3+)and Y~(3+)are 30.88,26.52,20.60,11.24 and 10.52 mg/g,respectively.Effects of some important parameters including GO-to-TAPA mass ratios,contact time,reaction temperature and initial Yb3+concentration on the adsorption were evaluated in detail.FTIR spectral and XPS analyses show that the metal complexations and ion exchanges between nitrogen/oxygen-containing species of the adsorbents and REEs are involved in the adsorption procedure besides the conventional adsorption based on specific surface area,indicating the introduction of specific molecules onto GO is beneficial to its adsorption ability.The convenient reusability and applicability of GO-TAPA_(x:y) composites toward real samples also demonstrate their feasibility in the enrichment of REE ions. 相似文献
105.
目的:探讨夏枯草水提取物对血管紧张素II诱导的血管平滑肌细胞(vascular smooth muscle cells,VSMCs)增殖作用及对Daxx/PTEN/NF-κB信号通路的影响。方法:培养VSMCs,体外用血管紧张素II (angiotensin II,Ang-II)(1 μmol/L)诱导细胞增殖模型,MTT和BrdU法分别检测夏枯草水提取物不同浓度(10、20、40、80、160 μg/mL)作用24 h后对VSMCs活性和增殖的影响、划痕法观察细胞迁移力,Western blot检测细胞中Daxx、PTEN、NF-κB蛋白表达。结果:与对照组比较,模型组VSMCs活力及细胞迁移能力明显增强;同时细胞中Daxx、PTEN蛋白表达明显降低,NF-κB蛋白显著上调;与模型组比较,20、40、80 μg/mL夏枯草水提取物成浓度依赖性显著抑制VSMCs活力与细胞迁移能力,以80 μg/mL浓度最显著;同时,夏枯草水提取物处理组细胞Daxx、PTEN蛋白表达明显上调,NF-κB蛋白下调。结论:夏枯草水提取物能显著抑制Ang-II诱导的VSMCs增殖与迁移,其机制可能与Daxx/PTEN/NF-κB信号通路有关。 相似文献
106.
目的:研究黄精多糖对睡眠干扰(sleep interruption,SI)诱导小鼠认知功能损伤的防治作用,并探讨其作用机制。方法:雄性ICR小鼠72只随机分为空白组、模型组、阳性对照(银杏叶提取物)组,黄精多糖低、中、高(100、200、400 mg/kg)组。预防给药14 d后,除空白组外,其它各组开始为期14 d的睡眠干扰。造模结束后依次进行旷场实验、物体认知实验、避暗实验、Morris水迷宫等行为学检测,并测定血清和海马组织中促炎细胞因子白介素-1β、白介素-6(IL-1β、IL-6)水平;海马组织中神经递质γ-氨基丁酸(GABA)、乙酰胆碱(Ach)水平。结果:旷场实验结果表明各组小鼠运动能力处于同一水平(P>0.05);与模型组相比,黄精多糖(100、200、400 mg·kg-1)给药后可以显著改善模型组小鼠在物体认知实验中相对辨别指数(DI)(P<0.05),延长避暗实验中入暗潜伏期(P<0.05)、减少错误次数(P<0.05),缩短水迷宫定位航行阶段的寻台潜伏期(P<0.05);黄精多糖给药组血清和海马中IL-6、IL... 相似文献
107.
目的 探讨一种催乳中药组方的催乳效果,研究其作用机制.方法 取产仔时间前后相差不超过24 h的50只母鼠,按母鼠体重随机分为正常组、模型组、催乳药物高、低剂量组和阳性对照组,每组10只母鼠.自分娩第2日起每天上午腹腔注射左旋多巴2 mg/kg,连续注射7d.于造模当日开始,每日下午给药,正常组蒸馏水灌胃,每日1次,连续给药14d.从给药第2日开始,每日测定母鼠泌乳量,并于给药14d后,处死动物,酶联免疫吸附测定法(ELISA法)检测血清泌乳素(PRL)和下丘脑5-羟色胺(5-HT)水平,同时取乳腺福尔马林固定,并进行病理形态学观察.结果 造模后正常组单次泌乳量和总泌乳量均显著高于模型组,表明产后缺乳大鼠造模成功.催乳药高、低剂量组的单次泌乳量、总泌乳量和血清PRL含量均显著高于模型组.催乳药高剂量组下丘脑5-HT含量高于模型组.结论 该催乳中药组方具有促进哺乳大鼠泌乳的作用,催乳机制可能是通过提高产后缺乳模型大鼠的血清PRL及下丘脑5-HT水平,使乳腺组织呈高度泌乳状态,从而促进乳汁分泌. 相似文献
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In order to meet the requirements of highly integrated and miniaturized electronic components, there is an urgent need for low dielectric materials with high mechanical properties and optical transparency in the field of microelectronics. In this study, a series of novel polyimide films (FPI) containing fluorenyl were prepared, and the effects of the fluorenyl content on the thermal, mechanical, and dielectric properties of the copolymerized films were investigated and discussed. The results demonstrate a significant decrease in the dielectric constant of the FPI films following the introduction of fluorenyl into polyimide (PI) chain segment. The FPI films also exhibited high mechanical properties, including tensile strengths between 92 and 106 MPa and elongation at break in the range of 8.4%–13.0%. Additionally, the introduction of the noncoplanar fluorenyl considerably improved the optical transparency and solubility of the FPI film. It is noteworthy that the FPI-3 has the best dielectric properties, with a low dielectric constant of 2.61 at 10 MHz and shows low water absorption (0.49%). The results show that we have prepared a novel low dielectric PI material film with excellent mechanical properties and optical transparency by introducing fluorenyl into the PI chain segment. These FPI films with satisfactory properties may be good candidates for dielectric materials for electronic components. 相似文献