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Plankton- Based Assessment of the Trophic state of Three Tropical Lakes

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Journal of Environmental Protection 2011年第3期2卷 304-315页

作者： Benedict Obeten Offem Ezekiel Olatunji Ayotunde Gabriel Ujong Ikpi F. B. Ada s. N. Ochang 不详

In developing countries, lakes being important sources of water.s.pply and fishing are vulnerable to anthropogenic impact, yet knowledge of their trophic state in relation to changes in species composition, and environmental variables, are limited. This study is aimed at assessing the trophic status of lakes by monthly sampling of three lakes located along the floodplain of Cr.s. river, Nigeria between January 2008 and December 2009. samples were analyzed for water quality parameters, zooplankton and phytoplankton composition and distribution. r.s.lts were subjected to community structure analysis using trophic state index, species richness and diversity indexes. Essential primary productivity nutrients, nitrates, sulphates and phosphates were highest in Ejagham Lake, and lowest in Ikot Okpora Lake. Dominant phytoplankton species Oscillatoria lacustria (Cyanophyceae), Cyclotella operculata (Bacilliarophyceae) and zooplankton Keratella tropica, Keratella quadrata, Filinia longiseta, Branchionus anguillar.s.and Trichocerca pusilla (rotifers) all typical of eutrophic communities were recorded in high densities in Ejagham Lake in both dry and wet seasons while Cladocerans, Bosmina longir.s.r.s.and Moina micrura and copepods considered indicators of oligotrophy and mesotrophy were recorded in large numbers in Ikot Okpora and Obubra Lakes r.s.ectively. Higher values of species richness, Evenness and shannon-wiener diversity index for both phytoplankton and zooplankton, were recorded in Ejagham Lake during the dry season than wet. Also values of the Trophic state index were generally highest at the Ejagham Lake in the savanna region of the floodplain and lowest at Ikot Okpora in the for.s. region of the floodplain. For.s. region is therefore a limiting factor in the productivity of lakes in the tropics.

关键词： Zooplankton Phytoplankton Trophic state Index Diversity Indices species richness

Photoprotective Effect of the Hydroalcoholic Extract from red and Black Peruvian Varieties of <i>Phaseolus vulgar.s.lt;/i>L.

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Journal of Biosciences and Medicines 2020年第11期8卷 46-59页

作者： L. Papuico-sánchez M. santa-Cruz-Ermitanio Juana E. Chávez-Flor.s.richard A. solórzano-Acosta Facultad de Farmacia y Bioquímica Universidad Norbert Wiener Lima Perú Departamento de Fitotecnia Universidad Nacional Agraria La Molina Lima Perú

Introduction: Ultraviolet radiation can be harmful to the skin and can create serious problems when a protective substance or equipment is not used regularly, for this reason the pr.s.nt study set out to evaluate the ... 详细信息

strong>Introduction:strong> Ultraviolet radiation can be harmful to the skin and can create serious problems when a protective substance or equipment is not used regularly, for this reason the pr.s.nt study set out to evaluate the photoprotective effect of the hydroalcoholic extracts of the integument of the red and black varieties of pop beans (Phaseolus vulgar.s./em>). strong>Materials and Method: strong>The extracts were obtained by macerating the tegument of the two varieties of pop beans, black and red, in an ethanol/water (80:20) solution. The thin-layer chromatographic method was used to observe anti-tyr.s.nase activity, using the 0.05% kojic acid standard as a positive control. The photoprotective effect was evaluated in female mice of seven-week-old, Mus musculus Balb/c, with shaved back and exposed to UV-C radiation for 30 minutes once a day for thirty days to induce photo-damage in the skin. The treatments consisted in the application of extracts at 2% and 5% W/V in gel on the shaved area. Only the gel formulation, sunscreen or no treatment at all was used for the control group. Acute photodamage was quantified using the Draize scale, measuring the degree of erythema and edema;and the degree of photoaging using the Glogau scale at 7 days and 30 days. strong>r.s.lts:strong> It was found that the ethanolic extracts of the integument of both varieties of Phaseolus vulgar.s./em>, red and black, are practically non-toxic in mice by oral and dermal routes at a limit dose of 5000 mg/kg. The anti-tyr.s.nase effect at a qualitative level, evaluated by thin layer chromatography, showed the black variety were more active than the red one and both can be compared to the activity of the kojic acid. The two extracts of the two varieties showed photoprotective effect, however the extracts in 5% gel to a greater degree.strong> Conclusions: strong>It was concluded that the hydroalcoholic extract of the pop black beans tegument at 5% in gel has

关键词： Anti-Tyr.s.nase Effect Photoprotective Effect Phaseolus vulgaris

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自适应横向滤波器长度的选择

声学技术 1980年第2期 26-31页

作者： W.s.Hod■kiss 方之炳

就均方误差含义下的最佳角度来说,能从已知输入统计特性导得的 wiener 滤波器是最佳线性滤波器。当这些统计特性是未知的时候,则采用最小均方误差(LMs)自适应滤波器就能使过滤问题获得极好的结果。梯度下降算法引入了一个正比于自适应... 详细信息

就均方误差含义下的最佳角度来说,能从已知输入统计特性导得的 wiener 滤波器是最佳线性滤波器。当这些统计特性是未知的时候,则采用最小均方误差(LMs)自适应滤波器就能使过滤问题获得极好的结果。梯度下降算法引入了一个正比于自适应滤波器长度的超量均方误差。在自适应基阵处理器中,LMs滤波器能构成一个从指定的接收波束中部分地去除旁瓣干扰源的噪声抵消器。本文推导自适应横向滤波器的最佳长度,从而使残余干扰信号能量加上由 LMs 算法引入的超量均方误差为最小。本文对窄带和宽带两种干扰信号均将进行探讨。

关键词：超量均方误差个数自适应滤波器自适应波束形成器自适应横向滤波器长度

robust Control for a Class of Markov switched Linear.s.stems with Linear Fractional Uncertainties

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Robust Control for a Class of Markov Switched Linear Systems...

基于通用赤池信息量准则改进维纳-格兰杰因果索引算法的颅内脑电效应连通性研究

第三十届中国控制会议

作者： HUANG Hongmei~(1,3),LONG Fei~(1,2),FU Pengwei~(1,2) 1.Institute of Intelligent Information Processing,Guizhou University,Huaxi,Guiyang Guizhou 550025,P.r.China 2.College of Computer.s.ience and Information,Guizhou University,Huaxi,Guiyang Guizhou 550025,P.r.China 3.Department of Mathematics College of science,Guizhou University,Huaxi,Guiyang Guizhou 550025,P.r.China

＜正＞The robust control problem for a class of continuous-time Markov switched linear.s.stems with wiener process disturbance with linear fractional uncertainties via switched state feedback and switched dynamic output feedback is investigated,*** attention is focused on the design of state feedback controllers and dynamic output feedback controllers so that the whole close-loop system is robust stochastic stabilization based on multiple Lyapunov function and LMI ***,two numerical examples are pr.s.nted to illustrate the effectiveness of the obtained theoretical r.s.lts.

关键词： Markov switched linear.s.stems robust stochastic stabilization Linear fractional uncertainties state feedback Dynamic output feedback LMIs

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生物医学工程学杂志 2018年第5期35卷 665-671页

作者：杨淳沨向文涛伍家松孔佑勇姜龙玉 Le Bouquin Jèannes régine 舒华忠东南大学计算机科学与工程学院计算机网络和信息集成教育部重点实验室南京210096 东南大学教育部信息显示与可视化国际合作联合实验室南京210096 法国国家医学与健康研究院U1099、雷恩第一大学信号与图像处理实验室法国雷恩35000 中法生物医学信息研究中心南京210096 中法生物医学信息研究中心法国雷恩35000

本文的目标是处理并分析使用深度电极在难治性癫痫患者癫痫发作期间其大脑皮层中记录到的癫痫脑电信号间的大脑效应连通性。维纳-格兰杰因果索引算法是一种众所周知的检测脑电信号间大脑效应连通性的有效方法。它是一种基于线性自回归... 详细信息

本文的目标是处理并分析使用深度电极在难治性癫痫患者癫痫发作期间其大脑皮层中记录到的癫痫脑电信号间的大脑效应连通性。维纳-格兰杰因果索引算法是一种众所周知的检测脑电信号间大脑效应连通性的有效方法。它是一种基于线性自回归模型的方法,而模型参数估计问题在其用于脑电因果效应连通性研究中的计算准确性与鲁棒性方面起着至关重要的作用。本文针对这一问题,使用了我们提出的改进的赤池信息量准则来估计算法中自回归模型的模型阶数,以提高维纳-格兰杰因果索引算法检测大脑效应连通性的性能。实验仿真结果表明:不管是在线性随机系统中还是在能生成模拟癫痫信号的生理模型中,该改进的维纳-格兰杰因果索引算法在检测脑效应连通性上都表现出良好的鲁棒性。

关键词：因果索引赤池信息量准则基于生理学的模型癫痫大脑连通性

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肺动脉高压患者中室间隔延迟对比增强的发生率及其相关因素

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世界核心医学期刊文摘（心脏病学分册） 2007年第12期3卷 28-29页

作者： sanz J. Dellegrottaglie s. Kariisa M. 刘少伟 The Zena and Michael A. wiener Cardiovascular Institute and Marie- Josee Henry R. Kravis Center for Cardiovascular Health Mount Sinai School of Medicine New York NY United States.Dr

已有观察描述了在心脏磁共振成像检查中,肺动脉高压(PH)患者室间隔的右室附着部位出现心肌延迟对比增强(DCE)。本研究的目的是观察该结果的发生率、程度和相关因素。在55例已确诊或疑似不同原因PH的患者中评估室间隔DCE。采用直观观察... 详细信息

已有观察描述了在心脏磁共振成像检查中,肺动脉高压(PH)患者室间隔的右室附着部位出现心肌延迟对比增强(DCE)。本研究的目的是观察该结果的发生率、程度和相关因素。在55例已确诊或疑似不同原因PH的患者中评估室间隔DCE。采用直观观察附着部位增强评分(0～4分)和DCE质量定量方法确定DCE程度。

关键词：室间隔右室室中隔肺动脉压力对比增强发生率患者相关因素

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自适应模糊文件图像的二值化

图象识别与自动化 2006年第1期 1-11页

作者： B．Gatos I．Pratikakis s．J．Perantonis 章晟译（译）

本文提出了一种新的自适应二值化方法，使模糊文件得到增强。这种方法不需要调整任何参数，它通过使用者及其对阴影、非均匀图像、低反差、大量的信号噪声、污点和变形等涉及的模糊情况，采用以下几个不同的步骤：低通wiener滤波器的预... 详细信息

本文提出了一种新的自适应二值化方法，使模糊文件得到增强。这种方法不需要调整任何参数，它通过使用者及其对阴影、非均匀图像、低反差、大量的信号噪声、污点和变形等涉及的模糊情况，采用以下几个不同的步骤：低通wiener滤波器的预处理，前景区域、背景表面的大致估算，背景表面与原始组合图像样本的组合计算以及最后的预处理过程，以改善文件的质量并保持笔划的连接。实验证明，本文的方法针对许多模糊图像具有优良的特性。

关键词：模糊文件图像局部自适应二值化

Identification of wiener Models with Binary-Valued Output Observations

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Identification of Wiener Models with Binary-Valued Output Ob...

Output-Feedback robust Adaptive Control for.s.rict-feedback stochastic Nonlinear.s.stems under Inverse Optimality Costs

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作者： Zhao Yanlong ,Wang Leyi, Yin Gang, Zhang Jifeng Academy of Mathematics and systems science,Chinese Academy of sciences,Beijing 100080 Department of Electrical and Computer Engineering,Wayne state University,Detroit,Michigan 48202,U. s. A. Department of Mathematics,Wayne state University,Detroit,Michigan 48202,U. s. A.

＜正＞This work focuses on system identification forwiener models,whose outputs are measured by binary sensors. It begins with the development of joint identifiability. Then, using periodic inputs, empirical distributions are used to construct identification algorithms. Convergence of the algorithms is established,and associated recursive algorithms are also developed.

关键词： Identification binary-valued observations wiener model joint identifiability.

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Output-Feedback Robust Adaptive Control for Strict-feedback ...