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Viability Loss Pattern under Rapid Dehydration of Antiaris toxicaria Axes and its Relation to Oxidative Damage

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Journal of Integrative Plant Biology 2010年第5期52卷 434-441页

作者： xia Xin Xin-ming Jing Yong Liu song-Quan song Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Graduate Schoolof the Chinese Academy of Sciences Beijing 100049 China Xishuangbanna Tropical Botanical Garden the Chinese Academy of Sciences Yunnan 666303 China

The relation between oxidative damage and viability loss of excised embryonic axes of Antiaris toxicaria subjected to rapid drying with silica gel at 15℃ was studied. Changes of survival rate, accumulation of thiobarbituric acid-reactive substances （TBARs）, activities of superoxide dismutase （SOD）, catalase （CAT）, ascorbate peroxidase （APX）, glutathione reductase （GR） and the permeability of cell membrane that was determined as relative electrolyte leakage （REL） were measured. The half-life moisture content （MC,50） was 0.41 g H=O/g DW （dry weight basis）. During drying, the activities of SOD, CAT and APX increased until MCL50, and declined thereafter. The generation speed of ·O2-, and content of H2O2 and TBARs remained steadily or even decreased at MC levels higher than MC,s0, demonstrating a low oxidative level in these axes. There was no significant correlation between viability loss and accumulation of reactive oxygen species or lipid peroxidation within the dehydration process until MCLs0. Whereas the increase in REL from the beginning of the drying process indicated that the cell membrane was damaged. In conclusion, under rapid drying with silica gel the viability loss of excised recalcitrant A. toxicaria axes seemed to be triggered by mechanical or physical damage, rather than metabolic damage.

关键词： ANTIARIS CELL membranes GLUTATHIONE SILICA

含3-芳基吡唑的饶丹宁衍生物的合成及抗菌活性评价

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井冈山大学学报（自然科学版） 2017年第5期38卷 96-103页

作者：彭姣阳林梦婷谭雨琪李松慧宋明霞井冈山大学医学院江西吉安343009

目的设计合成一系列含芳基吡唑的饶丹宁衍生物,用于抗菌活性的筛选。方法以盐酸氨基脲和不同取代的苯乙酮为起始原料,经亲核取代消除反应、维尔斯迈尔—哈克反应和缩合反应,得到了12个的3-芳基吡唑缩饶丹宁衍生物。采用连续稀释法评价1... 详细信息

目的设计合成一系列含芳基吡唑的饶丹宁衍生物,用于抗菌活性的筛选。方法以盐酸氨基脲和不同取代的苯乙酮为起始原料,经亲核取代消除反应、维尔斯迈尔—哈克反应和缩合反应,得到了12个的3-芳基吡唑缩饶丹宁衍生物。采用连续稀释法评价12个化合物对革兰氏阳性菌和革兰氏阴性菌的抑制活性。结果所合成化合物对革兰氏阴性菌未见抑制活性,部分化合物对革兰氏阳性菌显示出一定的抗菌活性,其中化合物3j对金黄色葡萄球菌(CMCC(B)26003)的抑菌活性MIC值达到32μg/mL。结论本研究合成的3-芳基吡唑缩饶丹宁衍生物对革兰氏阳性菌具有较弱的抑制活性,虽然活性强度未能达到预期目的,但该研究进一步丰富了饶丹宁类衍生物的抗菌构效关系,为新的抗菌活性化合物乃至候选药物的发现奠定了基础。

关键词：饶丹宁 3-苯基吡唑合成抗菌活性

3种重金属对斑马鱼的联合毒性及迷迭香酸的保护作用研究

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烟台大学学报（自然科学与工程版） 2020年第1期33卷 43-48页

作者：宋明霞陈天荣钱豪文许波烟台大学生命科学学院线粒体健康与衰老研究中心烟台大学

对氯化镉、硝酸铅、硫酸铜3种重金属单一以及联合情况下对早期斑马鱼胚胎发育毒性的影响进行考察,并采用不同浓度的迷迭香酸进行干预,同时观察96hpf胚胎的死亡率和孵化率.Cd-Pb、Cd-Cu、Pb-Cu、Cd-Pb-Cu对斑马鱼胚胎的毒性作用类型分别... 详细信息

对氯化镉、硝酸铅、硫酸铜3种重金属单一以及联合情况下对早期斑马鱼胚胎发育毒性的影响进行考察,并采用不同浓度的迷迭香酸进行干预,同时观察96hpf胚胎的死亡率和孵化率.Cd-Pb、Cd-Cu、Pb-Cu、Cd-Pb-Cu对斑马鱼胚胎的毒性作用类型分别为协同作用、协同作用、拮抗作用、协同作用.60μmol/LRA对斑马鱼胚胎死亡、幼鱼畸形及胚胎孵化率无明显影响.Cd2+-Pb2+-Cu2+联合处理,胚胎死亡率明显上升,60μmol/LRA与Cd2+-Pb2+-Cu2+联合处理,胚胎死亡率降低约20%(P<001);胚胎凋亡细胞数目明显减少,Bcl-2/Bax的基因表达水平明显上调(P<0.01),Caspase3基因表达下调(P<005).表明RA对Cd2+-Pb2+-Cu2+的联合毒性具有保护作用,其机制可能与上调Bcl-2/Bax,降低Caspase3基因表达,减少胚胎细胞凋亡有关.

关键词：斑马鱼重金属联合毒性迷迭香酸凋亡

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陆英有效部位抗菌活性研究

井冈山大学学报（自然科学版） 2021年第4期42卷 28-31页

作者：邓先清朱明辉谢权尹双红朱洋女朱明明宋明霞井冈山大学医学部江西吉安343009 井冈山大学中药资源和功能分子研究中心江西吉安343009

本实验利用陆英全草为研究对象,采用甲醇超声法和乙醇回流法对陆英干燥全草的有效成分进行提取,并将提取物分别用石油醚、乙酸乙酯和水萃取得到不同极性的萃取物组分。通过比较粗提物和萃取相的抑菌活性初步确定陆英的抗菌有效部位。结... 详细信息

本实验利用陆英全草为研究对象,采用甲醇超声法和乙醇回流法对陆英干燥全草的有效成分进行提取,并将提取物分别用石油醚、乙酸乙酯和水萃取得到不同极性的萃取物组分。通过比较粗提物和萃取相的抑菌活性初步确定陆英的抗菌有效部位。结果显示乙醇回流法的提取率较高,但甲醇超声法提取物活性更好。其中甲醇超声法石油醚萃取物活性最优,对大多数G^(+)及其耐药菌的最低抑菌浓度值达0.625~5.0 mg/mL。本研究初步确定甲醇超声法提取物的石油醚萃取部位是陆英的抗菌作用有效部位,这为陆英的药用开发,尤其是其抗菌领域的深入研究奠定了基础。

关键词：陆英有效部位抗菌活性耐药菌

Suppressed concentration quenching and tunable photoluminescence in Eu^(2+)-activated Rb_(3)Y(PO_(4))_(2)phosphors for full-spectrum lighting

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Light(Science & Applications) 2024年第11期13卷 2688-2698页

作者： ming Zhao Yeping Ge Yurong Li xiaoyan song Zhiguo xia Xinping Zhang Institute of Information Photonics Technology School of Physics and Optoelectronic EngineeringBeijing University of TechnologyBeijing 10083China College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaBeijing University of TechnologyBeijing 10083China State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied TechniquesGuangdong Engineering Technology Research and Development Center of Special Optical Fiber Materials and DevicesSchool of Physics and OptoelectronicsSouth China University of TechnologyGuangzhou 510641China

Highly efficient inorganic phosphors are desirable for lighting-emitting diode light sources,and increasing the doping concentration of activators is a common approach for enhancing the photoluminescence quantum yield(PLQY).However,the constraint of concentration quenching poses a great challenge for improving the ***,we propose a fundamental design principle by separating activators and prolonging their distance in Eu^(2+)-activated Rb_(3)Y(PO_(4))_(2)phosphors to inhibit concentration quenching,in which different quenching rates are controlled by the Eu distribution at various crystallographic *** blue-violet-emitting Rb_(3)Y(PO_(4))2:xEu(x=0.1%–15%)phosphors,with the occupation of Rb1,Rb2 and Y sites by Eu^(2+),exhibit rapid luminescence quenching with optimum external PLQY of 10%due to multi-channel energy ***,as the Eu concentration increases above 20%,Eu^(2+)prefer to occupy the Rb1 and Y sites with separated polyhedra and large interionic distances,resulting in green emission with suppressed concentration quenching,achieving an improved external PLQY of 41%.Our study provides a unique design perspective for elevating the efficiency of Eu^(2+)-activated phosphors toward high-performance inorganic luminescent materials for full-spectrum lighting.

关键词： quenching lighting concentration

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植物AGO蛋白的结构预测分析

吉林师范大学学报（自然科学版） 2015年第4期36卷 135-137,156页

作者：周晓馥宋明霞王晶徐洪伟吉林师范大学植物资源科学与绿色生产吉林省重点实验室吉林四平136000

AGO蛋白家族(Argonaute protein family)是RNA诱导沉默复合物(RISC)的功能核心,参与小RNA介导的基因沉默.AGO蛋白由N末端、PAZ、MID和PIWI四个结构域组成.它和小RNA在植物中共同参与维持基因组的稳定、调控组织发育、DNA修复、对逆境的... 详细信息

AGO蛋白家族(Argonaute protein family)是RNA诱导沉默复合物(RISC)的功能核心,参与小RNA介导的基因沉默.AGO蛋白由N末端、PAZ、MID和PIWI四个结构域组成.它和小RNA在植物中共同参与维持基因组的稳定、调控组织发育、DNA修复、对逆境的适应性应答以及在RNA层面对入侵核酸(转基因和植物病毒)的免疫.植物AGO蛋白在胚胎发育,细胞分化和转座子的沉默中具有重要作用.本文运用生物信息学的方法,结合生物信息学两大门户网站,对植物AGO蛋白的分类、平均疏水性、净电荷、不稳定系数等进行预测.

关键词： AGO蛋白生物信息学分类预测

5,7-二取代-[1,2,4]三唑[1,5-a]嘧啶衍生物的合成及其抗癫痫活性

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井冈山大学学报（自然科学版） 2022年第2期43卷 28-34页

作者：宋明霞程沐春曾希文邓先清井冈山大学医学部江西吉安343009 井冈山大学中药资源和功能分子研究中心江西吉安343009

通过合成一系列5,7-二取代-[1,2,4]三唑[1,5-a]嘧啶衍生物,对其体内抗癫痫活性进行研究。各种查尔酮和3-氨基-1,2,4-三氮唑在二甲基甲酰胺中加热反应分别得到5,7-二取代-4,7-二氢-[1,2,4]三唑[1,5-a]嘧啶(2a-2e)和它们的脱氢产物5,7-二... 详细信息

通过合成一系列5,7-二取代-[1,2,4]三唑[1,5-a]嘧啶衍生物,对其体内抗癫痫活性进行研究。各种查尔酮和3-氨基-1,2,4-三氮唑在二甲基甲酰胺中加热反应分别得到5,7-二取代-4,7-二氢-[1,2,4]三唑[1,5-a]嘧啶(2a-2e)和它们的脱氢产物5,7-二取代-[1,2,4]三唑[1,5-a]嘧啶(3a-3e)。通过核磁共振氢谱、碳谱和质谱进行化合物结构确证;采用最大电休克发作(MES)模型和皮下戊四唑(Sc-PTZ)模型评价化合物的抗癫痫活性,旋转棒法评价目标化合物的神经毒性。我们合成了5个5,7-二取代-4,7-二氢-[1,2,4]三唑[1,5-a]嘧啶衍生物和其脱氢产物。在MES模型中,化合物2a-2e均没有显示出抗癫痫活性,而化合物3a-3e则显示出不同程度的保护作用,说明脱氢后的产物活性高于未脱氢产物。在Sc-PTZ模型中,所有化合物在100 mg/kg剂量下都对戊四唑诱导的小鼠惊厥显示出保护作用。因此本研究报道的三唑[1,5-a]嘧啶衍生物具有较好的抗癫痫活性,进一步丰富了三唑类化合物的抗癫痫构效关系,为研究大发作和失神发作类癫痫的治疗药物提供了一定的基础。

关键词：三氮唑嘧啶抗癫痫最大电休克发作皮下戊四唑

Retrieving Aerial Scene Images with Learned Deep Image-SketchFeatures

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Journal of Computer Science & Technology 2017年第4期32卷 726-737页

作者： Tian-Bi Jiang Gui-song xia Qi-Kai Lu Wei-ming Shen State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China School of Electronic Information Wuhan University Wuhan 430072 China

This paper investigates the problem of retrieving aerial scene images by using semantic sketches, since the state-of-the-art retrieval systems turn out to be invalid when there is no exemplar query aerial image available. However, due to the complex surface structures and huge variations of resolutions of aerial images, it is very challenging to retrieve aerial images with sketches and few studies have been devoted to this task. In this article, for the first time to our knowledge, we propose a framework to bridge the gap between sketches and aerial images. First, an aerial sketch-image database is collected, and the images and sketches it contains are augmented to various levels of details. We then train a multi-scale deep model by the new dataset. The fully-connected layers of the network in each scale are finally connected and used as cross-domain features, and the Euclidean distance is used to measure the cross-domain similarity between aerial images and sketches. Experiments on several commonly used aerial image datasets demonstrate the superiority of the proposed method compared with the traditional approaches.

关键词： sketch aerial image retrieval multi scale deep cross-domain model

Stable Central Limit Theorems for Super Ornstein–Uhlenbeck Processes,Ⅱ

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Acta Mathematica Sinica,English Series 2022年第3期38卷 487-498页

作者： Yan xia REN Ren ming song Zhen Yao SUN Jian Jie ZHAO LMAM School of Mathematical Sciences&Center for Statistical Science Peking UniversityBeijing100871P.R.China Department of Mathematics University of Illinois at Urbana-ChampaignUrbanaIL61801USA School of Mathematics and Statistics Wuhan UniversityWuhan430072P.R.China The Faculty of Industrial Engineering and Management TechnionHaifa3200003Israel School of Mathematical Sciences Peking UniversityBeijing100871P.R.China

This paper is a continuation of our recent paper(***.,24(141),(2019))and is devoted to the asymptotic behavior of a class of supercritical super Ornstein-Uhlenbeck processes(X_(t))t≥0 with branching mechanisms of infinite second *** the aforementioned paper,we proved stable central limit theorems for X_(t)(f)for some functions f of polynomial growth in three different ***,we were not able to prove central limit theorems for X_(t)(f)for all functions f of polynomial *** this note,we show that the limiting stable random variables in the three different regimes are independent,and as a consequence,we get stable central limit theorems for X_(t)(f)for all functions f of polynomial growth.

关键词： Superprocesses Ornstein–Uhlenbeck processes stable distribution central limit theorem law of large numbers branching rate regime