507 research outputs found

    The research of typical microbial functional group reveals a new oceanic carbon sequestration mechanism——A case of innovative method promoting scientific discovery

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    海洋微型生物是海洋生物地球化学循环的主要驱动者,也是海洋能量代谢的主要参与者,在海洋生态系统中发挥着举足轻重的作用.好氧不产氧光合异养细菌(AAPB)是海洋中一类重要的功能类群,在海洋中广泛分布,它们可以利用光能补充自身的能量代谢,在海洋碳循环中发挥着重要而特殊的作用.在21世纪初,由于微型生物显微荧光定量方法的弊端,人们对于AAPB分布规律的认识存在着一定的偏差."时间序列红外荧光显微数字化方法"(TIREM)的建立,修正了AAPB定量偏差,揭示了海洋中AAPB分布的真正规律.之后,对AAPB生态分布调控因素的进一步研究表明:相对于光照,溶解有机碳(DOC)对AAPB绝对丰度和相对丰度的影响更重要.此认识推翻了"AAPB通过利用光能就可以赢得与普通异养细菌竞争"这一"想当然"的理论推测.而对AAPB碳源利用特点的研究表明,此功能类群具有重要的碳分馏作用,即AAPB在碳代谢过程中,部分碳源并非简单的沿着传统生物泵方向传递.在此基础上的海洋微型生物与DOC相互作用关系研究,最终导致海洋储碳新机制—微型生物碳泵(MCP)的提出,它解释了海洋中巨大溶解有机碳库存在的原因和机制,实现了海洋储碳机制理论上的新突破.科技部创新方法工作专项项目(编号:2011IM010700);; 国家自然科学基金项目(编号:41422603,41176095,91428308);; 国家海洋局专项项目(编号:GASI-03-01-02-03)资

    遥感-岩石力学(III)——交汇断层粘滑的热红外辐射与声发射规律及其构造地震前兆意义

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    以构造地震孕震机制之三即交汇断层粘滑发震为模拟对象,利用双轴加载实验系统和红外热像仪对自然界经常出现的断层组合模式——不同交汇角度的组合断层的物理模型进行了室内加载实验,利用红外热像仪和声发射仪分别测定了加载过程中试样表面的红外辐射及断层活动的声发射时间序列。结果表明:(1) 声发射及红外辐射的时间序列特征受加载过程中试样的力学行为所控制,并表现出阶段性变化特点;(2) 声发射与红外辐射特征与断层几何结构有密切关系,当主应力与主断层成45°角时,红外辐射异常区主要沿主断层发育;(3) 垂直交汇的断层与斜交断层的声发射及红外辐射特征有明显差异,交汇角度(1°~90°)越大,交汇点处的红外辐射异常越明显

    独活寄生汤水提物对退变大鼠椎间盘软骨细胞功能的影响

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    目的探究独活寄生汤水提物对经IL-1β诱导退变的大鼠椎间盘软骨细胞中Wnt4、GSK-3β、β-catenin、DKK-1的影响。方法采用机械-酶消化法分离大鼠椎间盘软骨组织,进行软骨细胞体外培养、镜下观察与鉴定,分为正常组、模型组(经10 ng/m L浓度IL-1β造模)、实验1组(独活寄生汤水提物组200μg/m L干预24 h)、实验2组(独活寄生汤水提物组200μg/m L干预48 h)。观察4组大鼠椎间盘软骨细胞中Wnt4、GSK-3β、β-catenin、DKK-1 m RNA与蛋白的表达及上清液中Sox 9表达。结果 (1)第2代大鼠椎间盘软骨细胞增殖速度快,呈现多边形,胞核清晰,且含有1~2个核仁,融合后出现\"铺路石\"状,经Ⅱ型胶原法染色后,阳性对照组胞浆区域浸染为棕黄色;(2)与正常组比较,模型组中软骨细胞Wnt 4、GSK-3β、β-catenin m RNA与蛋白表达及上清液Sox 9含量明显提高(P<0.05),DKK-1 m RNA与蛋白表达明显降低(P<0.05);与模型组比较,实验1组、实验2组中软骨细胞Wnt 4、GSK-3β、β-catenin m RNA与蛋白表达及上清液Sox 9含量明显降低(P<0.05),DKK-1m RNA与蛋白表达明显提高(P<0.05),以实验2组变化最为显著(P<0.05)。结论独活寄生汤水提物组可调控退变椎间盘软骨细胞的功能,下调Wnt 4、GSK-3β、β-catenin和上调DKK-1 m RNA与蛋白表达,进而延缓大鼠椎间盘软骨细胞的退变。福建省自然科学基金项目(2017J01224);;福建中医药大学校管课题资助(X2015034

    Classification method of diabetes based on integration of characteristic classifier

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    目的:结合医用电子鼻技术,探讨糖尿病患者及其口腔呼气的气味图谱特征。方法:选择180例糖尿病患者和100例健康者,用医用电子鼻采集280例口腔呼气的气味图谱,采用基于数据特征划分的方法,用支持向量机和随机森林集成模型对糖尿病患者进行分类预测。结果:1线性核函数的支持向量机(SVM1)分类结果不是很理想,低于多项式核(SVM2)、径向基函数核(SVM3)和随机森林(RF)3种分类器,说明分类超平面显然是非线性的;2集成分类器对糖尿病患者和健康者的气味图谱特征的识别准确率可达88.04%。结论:基于特征划分的分类器集成方法预测性能明显好于单一分类器,为使用医用电子鼻进行糖尿病诊断分析提供了一种有效手段。Objective: To discuss the proi le features of oral odor of diabetic patients based on medical electronic nose technology. Methods: 180 patients of diabetes and 100 healthy people were selected, and the proi le features of oral odor of 280 volunteers were collected by using medical electronic nose. The classii cation forecasting was carried out on diabetic patients by using support vector machine(SVM) and random forest integration model based on partitioning method of data characteristics. Results: 1The classii cation result of SVM1 was not very good, which was lower than that of SVM2, SVM3 and RF, and the result showed that the classii cation hyperplane is nonlinear. 2The accurate rate of recognition of integrated classii er on diabetic patients and healthy people is 88.04%. Conclusion: The forecasting performance of classii er integration method based on feature division is superior to that of single classii er signii cantly, which provided an ef ective means for the diagnostic analysis of diabetes based on medical electronic nose.国家自然科学基金项目(No.81373552);; 福建省教育厅A类项目(No.JA14212);; 福建工程学院科研启动项目(No.GY-Z12079)~

    The spatial and temporal distribution of virioplankton and heterotrophic bacteria in the coastal waters of Zhejiang

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    为了解浙江近海海域浮游病毒和异养细菌的时空生态分布,于2014年11月(秋)、2015年1月(冬)、2015年5月(春)和2015年7月(夏)连; 续4个季节采集了浙江近海海域表层海水样品,采用流式细胞仪技术对样品浮游病毒和异养细菌丰度进行了检测,对其时空分布特征及与环境因子的相关性做了分析; 。从水平分布来看,在4个季节中浮游病毒、异养细菌丰度均为宁波、沈家门、岱山等沿岸海域站位的丰度低,远陆海域东极和枸杞站位的丰度高。从季节变化来看; ,浮游病毒、异养细菌丰度的季节分布特征同为夏>春>秋>冬,相关性分析结果表明,春、夏、秋、冬4个季节,浮游病毒丰度与异养细菌丰度均为显著正相关。; 浮游病毒丰度在春、秋、冬季节均与病毒/细菌比值(VBR)显著正相关;夏、秋季节均与盐度显著正相关;春、夏季节均与总磷显著负相关;春季分别于与溶解; 氧、pH、化学耗氧量(COD)显著正相关。异养细菌在春、秋、冬季节均与VBR显著正相关;春、夏季节与溶解氧显著正相关,冬季与溶解氧显著负相关;春; 、夏季节与总磷显著负相关;秋、冬季节均与温度、盐度显著正相关;春、冬季节均与COD显著正相关。In order to investigate the spatial and temporal distribution of; virioplankton and heterotrophic bacteria in the coastal waters of; Zhejiang,the representative samples of sea water were collected in the; coastal waters of Zhejiang for 4 consecutive seasons in November; 2014(Autumn),January 2015(winter),May 2015(spring) and July; 2015(summer). The distribution of virioplankton and heterotrophic; bacteria was studied by flow cytometry,and the correlations between the; abundances of virioplankton,heterotrophic bacteria and environmental; factors were also analyzed. From the horizontal distribution,in the four; seasons low abundance of virioplankton and heterotrophic bacteria was in; the stations of Ningbo,Shenjiamen,Daishan immediate offshore; area;high-abundance was in the stations of Dongji and Gouqi offshore; area. From the seasonal distribution,the abundance of the virioplankton; and heterotrophic bacteria was the same as that of; summer>spring>autumn>winter. The abundance of virioplankton and; heterotrophic bacteria was significantly and positively correlated in; the 4 seasons. The abundance of virioplankton was significantly and; positively correlated with VBR in spring,autumn and winter. The; abundance of virioplankton was significantly and positively correlated; with salinity in summer and autumn. The abundance of virioplankton was; significantly and negatively correlated with TP in spring and summer.; The abundance of virioplankton was significantly and positively; correlated with dissolved oxygen,pH,COD in spring. The heterotrophic; bacteria were significantly and positively correlated with VBR in; spring,autumn and winter. The heterotrophic bacteria were significantly; and positively correlated with dissolved oxygen in spring and summer but; were significantly and negatively correlated with dissolved oxygen in; winter. The heterotrophic bacteria were significantly and negatively; correlated with TP in spring and summer. The heterotrophic bacteria were; significantly and positively correlated with temperature and salinity in; autumn and winter. The heterotrophic bacteria were significantly and; positively correlated with COD in spring and winter.国家海洋局公益性行业科研专

    独活寄生汤调控对大鼠椎间盘软骨细胞Wnt/β-catenin信号通路的影响

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    目的:从Wnt/β-catenin信号通路探讨独活寄生汤水提物对大鼠椎间盘退变软骨细胞功能的影响。方法:(1)用水提加热回流法制备独活寄生汤水提物成分;(2)选取4周龄健康雄性SD大鼠30只,采用机械-酶消化法分离大鼠椎间盘软骨组织,建立软骨细胞体外培养体系并进行鉴定;(3)RT-PCR、We stern blot法分别检测经DKK-1抑制剂干预及(或)经白细胞介素-1β诱导的椎间盘软骨细胞Wnt4、GSK-3β、β-catenin mRNA与蛋白含量的表达。结果:(1)椎间盘软骨细胞经Ⅱ型胶原法染色后,阳性对照组胞浆区域浸染为棕黄色;(2)RT-PCR、Western blot检测结果示,与正常组比较,模型组Wnt4、GSK-3β、β-catenin mRNA与蛋白含量表达显著升高(P<0.01);与模型组比较,独活寄生汤水提物组(100,200,400μg·mL-1)的Wnt4、GSK-3β、β-catenin mRNA与蛋白含量表达显著降低(P<0.01或P<0.05),其中以200μg·mL-1组的表达量最低(P<0.01)。结论:独活寄生汤水提物组可通过调控Wnt/β-catenin信号通路,下调大鼠椎间盘退变关节软骨中Wnt4、GSK-3β、β-catenin mRNA与蛋白含量表达,从而延缓椎间盘软骨细胞退变。福建省自然科学基金(2017J01224);;福建中医药大学校管课题(X2015034

    Spatial and Temporal Distribution of Picophytoplankton in Coastal Waters of Zhejiang

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    【目的】为了解浙江近海海域超微型光合自养浮游生物原绿球藻(Prochlorococcus,; Pro)、聚球藻(Synechococcus,Syn)和超微型真核浮游植物(Picoeukaryotes,Euk)的时空生态分布,【方法】于20; 14年11月(秋)、2015年1月(冬)、2015年5月(春)和2015年7月(夏)连续4个季节采集了浙江近海海域表层海水样品,采用流式细胞仪技; 术对样品超微型光合自养浮游生物丰度进行了检测,并对其时空分布特征及与环境因子的相关性进行了研究。【结果】从水平分布来看,在4个季节中超微型光合自; 养浮游生物丰度均为宁波、沈家门、岱山等沿岸海域站位的丰度低,远陆海域东极和枸杞站位的丰度高。从季节分布来看,原绿球藻的季节分布特征为夏季>秋季; >冬季>春季,聚球藻的季节分布特征为秋季 >冬季 >春季>夏季,超微型真核浮游植物的季节分布特征为夏季>秋季; >春季>冬季。相关性分析表明,春季,原绿球藻、聚球藻、超微型真核浮游植物均与pH显著正相关;秋季,原绿球藻、聚球藻、超微型真核浮游植物均与温度显; 著正相关;冬季,聚球藻、超微型真核浮游植物均与盐度显著正相关。【结论】本文超微型光合自养浮游生物丰度近岸海域明显低于远陆海域,这与近岸海域泥沙含; 量大,水色和透明度低有很大关系。浮游病毒对宿主的裂解也会影响超微型光合自养浮游生物的丰度变化。【Objective】 The preseat paper aims to investigate the spatial and; temporal distribution of picophytoplankton: Prochlorococcus,; Syn-echococcus and Picoeukaryotes in the coastal waters of; Zhejiang.【Method】 The representative samples of sea water in the coastal; waters of Zhejiang were collected for 4 consecutive seasons in November; 2014 (Autumn), January 2015 (winter),May 2015 (spring) and July 2015; (summer). The distributions of picophytoplankton by flow cytometry were; analyzed, and the correlation between the abundances of; picophytoplankton and environmental factors were studied.【Result】 From; the horizontal distribution, in the four seasons, the abundance of; picophytoplankton were low-abundance areas in the stations of; Ningbo,Shenjiamen, Daishan immediate offshore area, high-abundance areas; in the stations of Dongji and Gouqi offshore area. From seasonal; distribution, the abundance of Prochlorococcus was in order of summer >; autumn > winter > spring, the abundance of Synechococcus autumn > winter; > spring > summer; and the abundance of Picoeukaryotes summer > autumn >; spring > winter. Prochlorococcus,Synechococcus and Picoeukaryotes were; significantly positively correlated with pH in the spring.; Prochlorococcus,Synechococcus and Picoeukaryotes were significantly; positively correlated with temperature in autumn. Synechococcus and; Picoeukaryotes were positively correlated with salinity in; winter.【Conclusion】In this study, the abundance of picophytoplankton in; immediate offshore area was significantly lower than that of far; offshore area. The reason was that the sediment content was large,the; water color and transparency was low in immediate offshore area. The; cracking effect of the virioplankton on the host would affect the; abundance of picophytoplankton.国家海洋局公益性行业科研专

    微重力下板式贮箱内推进剂流动的研究

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    在卫星平台中,经常用液体推进剂贮箱为其提供能源保障,与其它类型的液体推进剂贮箱相比,第二代表面张力型推进剂贮箱,即板式贮箱,以其显著的性能优势和高可靠的特点成为了很多大型卫星推进剂贮箱的主流。板式贮箱的关键和核心部分是安装和布置在贮箱壳体内部的推进剂管理装置(PMD)。PMD功能的可靠实现,对保证卫星推进系统在空间正常工作具有直接的,决定性的作用和影响。为此,本文将对其进行研究,用三维气液平衡界面计算程序surface evolver对无重力下的板式贮箱中的液体形态进行模拟分析,为以后板式贮箱的设计提供参考

    Distribution Features and Speciation of Heavy Metals in Surface Sediments of Main Mangrove of China

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    利用ICP-MS分析了我国红树林主要分布区表层沉积物的As含量和形态,阐明As的分布及其形态特征.结果表明,表层沉积物中w(As)为3.14~19.16mg/g,平均值为8.14mg/g.表层沉积物中w(As)与w(Fe),w(Mn),pH,w(有机质),粉粒和黏粒所占比例呈显著或极显著正相关.表层沉积物中的As主要以残渣态存在,其次为有机质-硫化物结合态.在整个研究区域,As的5种形态在总量中的所占比例:可交换离子态为14.40%,碳酸盐结合态为1.41%,铁锰氧化物结合态为2.16%,有机质-硫化物结合态为30.40%,残渣态为50.65%.可交换离子态所占比例与w(有机质)和pH呈极显著正相关.有机质-硫化物结合态所占比例与盐度、黏粒和粉粒所占比例呈显著或极显著正相关.残渣态所占比例与盐度、粉粒和黏粒所占比例呈极显著正相关.Arsenic contents in surface sediments collected from mangrove were analyzed with a PE DRC-e ICP-MS,and the distribution and species of As were identified.The results showed that As content ranged from 3.14~19.16 mg/g,with an average content of 8.14 mg/g.As content correlated well and positively with the contents of Fe and Mn,pH,organic content,silt and clay.Residual As was the primary species,and organic and sulfide As were the secondary species in the surface sediments.Among five As species,the exchangeable As accounted for 14.40%,carbonate As accounted for 1.41%,Fe-Mn oxides As accounted for 2.16%,organic-sulphide As accounted for 30.40%,and residual As accounted for 50.65%.Exchangeable As positively correlated with organic content and pH significantly.Organic-sulfide As and residual As positively correlated with salinity,silt and clay significantly.国家自然科学基金项目(40676064,30530150
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