增长曲线模型回归系数的线性MINIMAX估计

在矩阵损失函数下 ,研究增长曲线模型中回归系数的线性估计在给定估计类中的minimax性 ,并得到惟一的线性 minimax估计 .

自适应H-minima的改进分水岭堆叠细胞分割方法

针对传统分水岭方法初始分割结果存在过分割问题,提出自适应H-minima的改进堆叠细胞分割方法。该方法利用不同h值H-minima变换抑制种子噪声,并以对应候选种子为中心,分别采用改进K-均值算法合并初始分割区域,产生候选分割结果;然后,基于形状先验定义圆度指标FuzzyR,并将堆叠细胞平均圆度作为评价函数,自适应提取各堆叠区域最优h值,实现正确分割。实验结果证明,针对于人工合成和真实堆叠细胞图像,算法均能有效抑制过分割、减少欠分割,分割性能显著提高。

豇豆属近缘野生种Vigna minima资源收集与表型性状初步研究

Vigna minima是豇豆属中的野生种,国内研究报道较少。本研究对搜集到的V.minima野生资源的地理分布、原生境主要性状、遗传多样性及其与野生小豆、栽培小豆性状间的差异进行了分析。结果表明:(1)搜集到的45份V.minima野生资源来源于辽宁、天津、河北、山东和北京等省、直辖市,资源在粒色、子粒大小、植株形态等方面变异丰富。(2)与栽培小豆相比,V.minima株型大,上胚轴短,叶片小,荚果细短,炸荚性强,荚色深,子粒小,粒色多样。植株和子粒性状与野生小豆相近,但种脐突出明显,且种脐长。(3)V.minima与栽培小豆间亲缘关系较远,而与野生小豆间亲缘关系较近。(4)不同地域间V.minima遗传多样性丰富,同一地域内不同材料间也存在遗传差异。

Effect of ethanolic extract of Physalis minima on lowering blood pressure in DOCA-salts hypertensive rat models

OBJECTIVE To explore the effect of ethanolic extract of Physalis minima on lowering blood pressure in the DOCA-salts hypertensive rats.METHODS To produce hypertension,male rats were induced DOCA at dose of 10mg·kg-1 ip.twice weekly and 0.9% NaCl in drinking water ad libitum for six weeks.The ethanolic extract of Physalis minima were given at dose of 500,1500 and 2500mg·kg-1,respectively for 4weeks.After completion of treatment schedule,systolic blood pressure was evaluated using animal blood pressure analyzer.The serum nitric oxide levels was measured using the ELISA methods.SOD activity and MDA level were determined spectrophotometrically.Endothelial dysfunction was determined by acetylcholine-induced vasorelaxation studies on isolated rat aortas.RESULTS The extract decreased systolic blood pressure significantly(P<0.001)in hypertensive rats.In addition,the extract also suppressed the production of MDA and restored SOD activity to normal level.There was a reduced relaxation response to acetylcholine in isolated aortic rings and serum NO level from hypertensive rats that were reversed by extract.CONCLUSION Physalis minima can lower blood pressure in hypertensive rats and its mechanism may be through the improvement of endothelial function due to the decrease of stress oxidative.

Methanolic extract of ceplukan leaf(Physalis minima L.)attenuates ventricular fibrosis through inhibition of TNF-α in ovariectomized rats

OBJECTIVE To investigate the effects of ceplukan leaf(Physalis minima L),which contain phytoestrogen physalin and withanolides,toward ventricular TNF-αlevel and fibrosis in ovariectomized rats.METHODS Wistar rats divided into six groups(K1:normal;K2:5 weeks ovariectomy(OVX);K3:9weeks ovariectomy(OVX),K4,K5,and K5:9weeks OVX+4 weeks ceplukan leaf's methanolic extract dose 500,1500,and 2500 mg·kg-1,respectively.TNF-αlevel measured with ELISA method.Fibrosis measured as blue color percentage in Masson′s Trichrome staining.RESULTS This study showed that prolonged hypoestrogen increase ventricular fibrosis(P<0.05).Ceplukan leaf treatment also resulted in a decreased ventricular fibrosis and TNF-αlevel in dose dependent manner compared with those of without treatment group(P<0.05).Furthermore,the TNF-αlevel normalized in rat treated with 2500mg·kg-1 Physalis minima L(P<0.05).Reduction of fibrosis positively correlated with TNF-αlevel(P<0.05,r= 0.873).CONCLUSION Methanolic extract of ceplukan leaf decrease ventricular fibrosis through inhibition of ventricular TNF-αin ovariectomized rats.Duration of hypoestrogen increase ventricular fibrosis.

The Amplification and Application of Ribosomal RNA (rDNA) Gene Sequences of <i>Blidingia minima</i>(Chlorophyta, Blidingia)

The sequence of the ribosomal RNA gene (rDNA) plays an important role in species identification and phylogenetic analysis. However, the only published full-length sequence of a ribosomal gene of green algae is that of Ulva mutabilis. In this study, we amplified the full-length sequence of each ribosomal gene unit of the ribosomal gene of Blidingia minima. The full-length sequence of the ribosomal gene in Blidingia minima is 8676 bp, including the 1759 bp 18S rDNA, 576 bp internal transcribed spacer (ITS) + 5.8S rDNA, 3282 bp 28S rDNA, and 3059 bp intergenic spacer (IGS) region. We then carried out a series of genetic analyses based on the ITS and IGS sequences, to verify whether IGS sequences are useful for studying the genetic diversity of green algae from different locations. We amplified the IGS sequences of Blidingia minima from 10 different locations in the Yellow Sea. Multiple alignments of the IGS sequences of samples from these 10 different sites revealed varying degrees of base differences, and comparative analysis of the ITS sequences revealed that our amplified species was classified as Blidingia minima and distinct from other green algae. In conclusion, our full-length amplified ribosomal gene provides useful information to enrich the data on green algae ribosomal genes and provides an effective molecular marker for the analysis of the interspecies and intraspecies relationships of Blidingia minima.

Non-Parametric Local Maxima and Minima Finder with Filtering Techniques for Bioprocess

Typically extrema filtration techniques are based on non-parametric properties such as magnitude of prominences and the widths at half prominence, which cannot be used with data that possess a dynamic nature. In this work, an extrema identification that is totally independent of derivative-based approaches and independent of quantitative attributes is introduced. For three consecutive positive terms arranged in a line, the ratio (R) of the sum of the maximum and minimum to the sum of the three terms is always 2/n, where n is the number of terms and 2/3 ≤ R ≤ 1 when n = 3. R > 2/3 implies that one term is away from the other two terms. Applying suitable modifications for the above stated hypothesis, the method was developed and the method is capable of identifying peaks and valleys in any signal. Furthermore, three techniques were developed for filtering non-dominating, sharp, gradual, low and high extrema. Especially, all the developed methods are non-parametric and suitable for analyzing processes that have dynamic nature such as biogas data. The methods were evaluated using automatically collected biogas data. Results showed that the extrema identification method was capable of identifying local extrema with 0% error. Furthermore, the non-parametric filtering techniques were able to distinguish dominating, flat, sharp, high, and low extrema in the biogas data with high robustness.

New Thymol Derivate from Centipeda minima

1 Introduction Centipeda minima(Compositae) is an annual herbaceous plant found in moist places throughout the plains mainly in the southern regions of the People’s Republic of China, Eastern tropical Asia,

Local minima-free design of artificial coordinating fields

In order to overcome the drawbacks of conventional artificial potential fields (APF) based methods for the motion planning problems of mobile robots in dynamic uncertain environments,an artificial coordinating fields (ACF) based method has been proposed recently.This paper deals with the reachability problem of the ACF,that is,how to design and choose the parameters of the ACF and how the environment should be such that the robot can reach its goal without being trapped in local minima.Some sufficient conditions for these purposes are developed theoretically.Theoretical analyses show that,the ACF can effectively remove local minima in dynamic uncertain environments with V-shape or U-shape obstacles,and guide the mobile robot to reach its goal with some necessary environment constraints and based on the methods provided in this paper to properly choose the parameters of the ACF.Comparisons between the ACF and APF,and simulations are provided to illustrate the advantages of the ACF.

THE REGULARITY OF QUASI-MINIMA AND ω-MINIMA OF INTEGRAL FUNCTIONALS

In this article, we have two parts. In the first part, we are concerned with the locally Hlder continuity of quasi-minima of the following integral functional ∫Ωf(x, u, Du)dx, (1) where Ω is an open subset of Euclidean N-space (N ≥ 3), u:Ω→ R,the Carath′eodory function f satisfies the critical Sobolev exponent growth condition |Du|p* |u|p*-a(x) ≤ f(x,u,Du) ≤ L(|Du|p+|u|p* + a(x)), (2) where L≥1, 1<p<N,p* = Np/N-p , and a(x) is a nonnegative function that lies in a suitable Lp space. In the second part, we study the locally Hlder continuity of ω-minima of (1). Our method is to compare the ω-minima of (1) with the minima of corresponding function determined by its critical Sobolev exponent growth condition. Finally, we obtain the regularity by Ekeland’s variational principal.

Influence of the initial electronic state on minima of high-order harmonic spectrum radiated from hydrogen molecular ion

We theoretically investigate the high-order harmonic generation of the one-dimensional hydrogen molecular ion at fixed intermediate internuclear distance, driven by a multicycle laser field. Our results show that the initial electronic state of the hydrogen molecular ion affects the modulation of the high-order harmonic spectrum, especially the positions of the minima. Based on the two-state model, the underlying physical mechanism of the minimum is analyzed and discussed.Further analysis shows that the different positions of the minima in the different initial electronic states can be understood via the different interferences of the two phase-adiabatic states at the ionization times.

GLOBAL WEAK SHARP MINIMA AND COMPLETENESS OF METRIC SPACE

A sufficient condition on the existence of a global weak sharp minima for general function in metric space is established. A characterization for convex function to have global weak sharp minima is also presented, which generalized Burke and Ferris'result[1] to infinite dimensional space. A characterization of the completeness of a metric space is given by the existence of global weak sharp minima.

The myth of “minima” and “maxima”,the species of Physalis in the Indian Subcontinent

The status of the names, Physalis minima L. and P. maxima Mill. (Solanaceae), and their alleged presence on the Indian subcontinent are discussed. The issues of nativity and identity of Linnaean Physalis minima are long-debated while the use of the name P. maxima Mill. and its report from India are recent. The available evidence indicates that the name "P. minima L." is misapplied to two different elements, viz., P. angulata L. and P. lagascae Roem. & Schult. The name Physalis minima L. may be rejected as nomen confusum, for which the paper provides the primary information. As on today, it is submerged under the synonymy of P. angulata L. The correct name for the widely known P. minima is P. lagascae. The name "P. maxima Mill." applied to the escape and naturalized weed in the Indian subcontinent and elsewhere is to be substituted by P. pruinosa L., a name misapplied to P. grisea (Waterf.) M. Martínez.

Collision risk assessment of reduced aircraft separation minima in procedural airspace using advanced communication and navigation

With the advancement of Communication,Navigation and Surveillance(CNS)technolo-gies such as space-based Automatic Dependent Surveillance-Broadcast/Contract(ADS-B/C),large separation minima may be reduced in procedural airspaces.It is of great significance to know the upper limit of the Reduced Separation Minima(RSM)for a procedural airspace and the corre-sponding consequences on collision risk with specifics of the advanced ADS-B and control interven-tion model.In this work,an interactive software is first developed for collision risk estimation.This software integrates the International Civil Aviation Organization(ICAO)collision risk models for lateral and longitudinal collision risk calculation for the Singapore procedural airspace.Results demonstrate that the lateral and longitudinal collision risk of Singapore procedural airspace with respect to current control procedures meets the ICAO Target Level of Safety(TLS)standard.Moreover,the feasibility of reducing the horizontal separations implemented in the Singapore pro-cedural airspace with respect to advanced CNS techniques is investigated.It is found that if advanced CNS technologies are applied,then the current 50-NM lateral and longitudinal separa-tion standards can be reduced to 22 NM(1 NM=1.825 km)and 20 NM,respectively,to meet the TLS standards based on current demand.A method is then devised to expand the traffic demand by p for p∈[10%,200%].It is found that the minimum lateral and longitudinal separa-tions can be reduced from 50 NM to be within the range of[23,31]NM,and 20 NM,respectively,for p∈[10%,200%],while the collision risk still meets the TLS standards.

基于改进人工势场法的通用航空路径规划

通用航空飞机在飞行过程除了要面对障碍物和天气系统的威胁,同时也受到飞行空域的限制,往往飞机只能在一块固定的空域或狭小的飞行走廊内飞行,一旦飞出限制空域,则有可能引发飞行冲突,甚至发生严重的安全事故。针对这些问题,在人工势场法斥力势场函数中添加航空器和目标点之间的相对距离函数,首先解决传统人工势场法存在的目标不可达问题和局部极小点问题,然后在算法中加入航路边界斥力影响因子,使飞机避障后在边界斥力的作用下重回航路中心。经过MATLAB仿真验证,试验结果表明,改进后的人工势场法能够实现主动避障和飞机航迹的规划。

基于迭代H-minima改进分水岭算法的高分辨率遥感影像单木树冠提取

从高分辨率遥感影像中提取单木树冠信息能够有效提高森林资源的调查与管理水平;针对现有单木树冠提取方法对郁闭度较高的阔叶林提取精度低的问题,提出一种基于迭代H-minima改进分水岭算法的高分辨率遥感影像单木树冠提取方法;首先利用形态学开操作对图像进行平滑处理,采用Sobel算子提取梯度图像,并利用均值滤波进行去噪处理;然后利用一组h值在梯度图像上迭代识别树冠标记,利用虚假标记检测方法过滤无效标记;最后引入对称原则来限制分水岭算法的淹没过程,避免树冠标记过生长与无标记树冠合并;以高分辨率遥感影像作为数据源,同时采用传统的标记控制分水岭算法和所算法提取单木树冠,从单木位置和树冠轮廓两个方面,以及样地和单木两个尺度上对单木树冠提取的精度进行评价。结果表明:所提算法提取树冠的F测度为92.71%,比标记控制分水岭算法提高了31.99%;所提算法能够有效抑制过分割、减少欠分割,从而提高单木树冠的提取精度。

NEW GUAIANOLIDES FROM Centipeda minima

Ⅰ. NEW GUAIANOLIDES FROM CENTIPEDA MINIMA The Chinese medical herb Centipeda minima (L.) A. Br. et Ascher (Compositae) has been used for treatment of rhinitis, sinusitis and nasopharynger tumor. Previous chemical investigations only gave steroids and triterpenes and cis-chrysanthenyl acetate. A reinvestigation of the dried drug (whole plant) afforded in addition to the triterpenes and steroids 10-isobutyryloxy-8, 9-epoxithymol-isobutyrate 6, the derivatives 1 and 2, three pseudoguaianolides, arnicolide 7, brevilin8 and helenalin 9, as well as three guaianolides, the 2-O-esters of florilenalin 3—5.

鹅不食草的化学成分及药理作用研究进展

鹅不食草是我国传统中药,具有发散风寒、止咳、通鼻窍的功效,在临床上主要应用于鼻炎、鼻窦炎、鼻咽癌的治疗。鹅不食草的主要化学成分包括萜类、黄酮类、挥发油、甾醇类及酚类等。本文较为全面地总结其164个化学成分及结构特征,并进行分类整理。鹅不食草及其成分具有抗肿瘤、抗氧化、抗炎、抗菌、抗过敏、肝脏保护、抗病毒等多种药理活性。本文对鹅不食草的化学成分、药理作用研究进展作一综述,以期为鹅不食草的进一步研究提供思路,为鹅不食草的开发及应用提供参考。

HOMOGENIZATION PROBLEMS OF PARABOLIC MINIMA

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等离子体环境中相对论效应对类氢离子光电离过程的影响

本文在偶极近似下计算了Debye等离子体环境中C^(5+),Al^(12+)和W^(73+)离子的光电离截面,重点研究了相对论效应对势形共振、Cooper极小和虚态效应的影响.研究结果表明,相对论效应随核电荷数的增大而增大,使得精细结构劈裂越来越显著,在光电离截面中出现了双共振结构的现象,并且共振峰的大小、宽度和位置的差异都随着核电荷数的增加而越来越大;分截面出现Cooper极小位置的差异也越来越大,在总截面中叠加的极小值越来越浅;出现虚态效应的等离子体屏蔽长度以及低能区光电离截面虚态增强的截面值也存在明显差异.