高压离子交换柱柱效初探及镧系元素的快速制备分离

本文探讨了操作条件与高压离子交换柱柱效的关系,研究了洗脱液梯度以及交换柱直径与树脂床高度比例对镧系元素分离的影响。在选定的最佳分离条件下,用自制高压离子交换色谱仪和国产阳离子交换树脂实现了除钷以外的所有镧系元素的快速分离,相邻元素之间皆达到了基线分离。

First molluscan TNFR homologue in Zhikong scallop: Molecular characterization and expression analysis

Tumor necrosis factor receptors (TNFRs) are a superfamily of proteins characterized by the unique cysteine-rich domain (CRD) and their important roles in diverse physiological and pathological events such as inflammation, apoptosis, autoimmunity and organogenesis. The first member of the molluscan TNFR family, designated as CfTNFR, was identified from Zhikong scallop Chlamys farreri by expressed sequence tag (EST) and rapid amplification of cDNA ends (RACE) approaches. The full-length cDNA of CfTNFR was of 1334 bp, consisting of a 5' UTR of 17 bp, a 3'UTR of 69 by with a poly (A) tail, and an open reading frame (ORE) of 1248 by encoding a polypeptide of 415 amino acids with a theoretical isoelectric point of 8.33 and predicted molecular weight of 47.07 kDa. There were a signal peptide, a CRD, a transmembrane region and a death domain in the deduced amino acid sequence of CfTNFR, suggesting that it was a typical type 1 membrane protein. The high identities (22-40%) of CfTNFR with other TNFR superfamily members indicated that CfTNFR should be a member of TNFR superfamily, and moreover, it should be the first death domain-containing TNFR found in invertebrates. Phylogenetic analysis revealed that CfTNFR was closely related to TNFR-like proteins from Strongylocentrotus purpuratus, Drosophila melanogaster and Ciona intestinalis, and they formed a separate branch apart from vertebrate TNFRs. The spatial expression of CfTNFR transcripts in healthy and bacteria challenged scallops was examined by quantitative real-time PCR. CfTNFR transcripts could be detected in all tested tissues, including haemocytes, gonad, gill, mantle and hepatopancreas, and significantly up-regulated in the tissues of gonad, gill, mantle and hepatopancreas after Listonella anguillarum challenge, indicating that CfTNFR was constitutive and inducible acute-phase protein involved in immune defence. The present results suggested the existence of the TNFR-like molecules and TNF-TNFR system in low invertebrates, and provided new insights into the role of CfTNFR in scallop innate immune responses to invading microorganisms. (C) 2009 Elsevier Ltd. All rights reserved.

Identification and analysis of a Sciaenops ocellatus ISG15 homologue that is involved in host immune defense against bacterial infection

ISG15 is an interferon-stimulated gene that encodes a ubiquitin-like protein. ISG15 homologues have been identified in a number of fish species, some of which are known to be regulated at expression level by virus infection and lipopolysacchande (LPS) treatment However, the relationship between ISG15 and live bacterial infection has not been investigated in piscine models. In this study, an ISG15 homologue, SoISG15, was identified from red drum Scraeriops ocellaws and analyzed at expression and functional levels The open reading frame ofSolSG15 is 477 base pairs (bp) and mtronless, with a 5'-untranslated region (UTR) of 91 bp and a 3'-UTR of 415 bp The deduced amino acid sequence of S0ISG15 shares 60-67% overall identities with the ISG15 of several fish species. S0ISG15 possesses two conserved ubiquinn-like domains and the canonical ubiquitin conjugation motif, LRGG, at the C-terminus. Expressional analysis showed that constitutive expression of SolSG15 was highest in blood and lowest in kidney Experimental challenges with LPS and bacterial pathogens induced significant S0ISG15 expression in the kidney but not in the liver Similar differential induction was also observed at cellular level with primary hepatocytes and head kidney (HK) lymphocytes. Poly(' C), however, effected drastic induction of S0ISG15 expression in kidney and liver at both tissue and cellular levels. Immunoblot analysis showed that S0ISG15 was secreted by cultured HK lymphocytes into the extracellular milieu. Recombinant S0ISG15 expressed in and purified from Eschenclua colt was able to enhance the respiratory burst activity, acid phosphatase activity, and bactericidal activity of HK macrophages. Taken together, the results of this study indicated that SoISG 15 possesses apparent immunological property and is likely to be involved in host immune defense against bacterial infection. (C)2010 Elsevier Ltd All rights reserved.

Characteristics of shallow gas hydrate in Okhotsk Sea

Multidisciplinary field investigations were carried out in Okhotsk Sea by R/V Akademik M.A. Lavrentyev (LV) of the Russian Academy of Sciences (RAS) in May 2006, supported by funding agencies from Korea, Russia, Japan and China. Geophysical data including echo-sounder, bottom profile, side-scan-sonar, and gravity core sample were obtained aimed to understand the characteristics and formation mechanism of shallow gas hydrates. Based on the geophysical data, we found that the methane flare detected by echo-sounder was the evidence of free gas in the sediment, while the dome structure detected by side-scan sonar and bottom profile was the root of gas venting. Gas hydrate retrieved from core on top of the dome structure which was interbedded as thin lamination or lenses with thickness varying from a few millimeters to 3 cm. Gas hydrate content in hydrate-bearing intervals visually amounted to 5%-30% of the sediment volume. This paper argued that gases in the sediment core were not all from gas hydrate decomposition during the gravity core lifting process, free gases must existed in the gas hydrate stability zone, and tectonic structure like dome structure in this paper was free gas central, gas hydrate formed only when gases over-saturated in this gas central, away from these structures, gas hydrate could not form due to low gas concentration.

Chromosome inheritance in triploid Pacific oyster Crassostrea gigas thunberg

Reproduction and chromosome inheritance in triploid Pacific oyster (Crassostrea gigas Thunberg) were studied in diploid female x triploid male (DT) and reciprocal (TD) crosses. Relative fecundity of triploid females was 13.4% of normal diploids. Cumulative survival from fertilized eggs to spat stage was 0.007% for DT crosses and 0.314% for TD crosses. Chromosome number analysis was conducted on surviving progeny from DT and TD crosses at 1 and 4 years of age. At Year 1, oysters from DT crosses consisted of 15% diploids (2n = 20) and 85% aneuploids. In contrast, oysters from TD crosses consisted of 57.2% diploids, 30.9% triploids (3n = 30) and only 11.9% aneuploids, suggesting that triploid females produced more euploid gametes and viable progeny than triploid males. Viable aneuploid chromosome numbers included 2n + 1, 2n + 2, 2n + 3, 3n - 2 and 3n - 1. There was little change over time in the overall frequency of diploids, triploids and aneuploids. Among aneuploids, oysters with 2n + 3 and 3n-2 chromosomes were observed at Year 1, but absent at Year 4. Triploid progeny were significantly larger than diploids by 79% in whole body weight and 98% in meat weight at 4 years of age. Aneuploids were significantly smaller than normal diploids. This study suggests that triploid Pacific oyster is not completely sterile and cannot offer complete containment of cultured populations.

Steroids from green alga Chaetomorpha basiretorsa Setchell

Six steroids have been isolated from ethanolic extract of green alga Chaetomorpha basiretorsa Setchell by a combination of repeated normal phase silica gel and Sephadex LH-20 gel column chromatography as well as recrystallization. Using spectroscopic methods including MS and NMR, their structures were determined as beta-lawsaritol (1), saringosterol (2), 24-hydroperoxy-24-vinyl-cholesterol (3), beta-stigmasterol (4), stigmast-4-en-3 alpha, 6 beta-diol (5), 29-hydroxystigmasta-5, 24 (28)-dien-3 beta-ol (6). All these compounds were obtained from this genus for the first time and they were inactive (IC50 > 10 mu g /ml) against KB, Bel-7402, PC-3M, Ketr 3 and MCF-7 cell lines.

青海湖布哈河下游地区植物群落多样性研究

根据野外样方调查资料，对青海湖西部布哈河下游地区8种植物群落进行了研究。结果表明：群落的多样性随丰富度的降低而呈下降趋势，均匀度的变化受物种丰富度的影响不大，群落的物种多样性指数与丰富度指数和均匀度指数均表现出极显著的正相关性（P〈0．01），相关系数分别为0．912和0．684；群落的均匀度与丰富度相关性不显著，说明物种多样性主要为物种丰富度所推动。

中药鸦胆子化学成分及药理学研究进展

鸦胆子系苦术科鸦胆子属植物（Brncea Javaniea L．Merr）的种子，始载干《本草纲目拾遗》Kupchan等报道了由B．antidysenter Mill．中分得对多种动物菌株有显著活性且毒性较低的鸦胆丁（Bruceantin）后，有关活性成分的报道引起了人们极大的关注，进一步研究发现了许多新的具有抗肿瘤活性的苦木内酯类化合物。我国于1978开始研制鸦胆子油静脉乳剂，并用于治疗各种恶性肿瘤。鉴于该植物的多种生物活性，为了更好地开发其药用价值，本文就其化学成分和药理作用的研究进展做一综述。

禾本科叶片表皮结构细胞的组合式样及其分类学意义

利用光学显微镜，对禾本科204属373种植物的叶片表皮进行了观察。发现禾本科叶片表皮细胸细胞在下表面上的分布式样可以划分为5个基本类型，即竹型、稻型、黍型、虎尾草型和早熟禾型，而5个基本类型所附属的植物类群分别是禾本科中的竹亚科、稻亚科、虎尾草亚科早熟禾亚科。同时分析了这5个类型的演化水平，并同类群的外部形态、地理分布相印证，表明竹亚科最原始、稻亚科次之、黍亚科演化居中、虎尾草亚科较高级、早熟禾亚科最高级；禾本科可能起源于世界的热带区域。

The effect of land management on carbon and nitrogen status in plants and soils of alpine meadows on the Tibetan plateau

Large-scale grassland rehabilitation has been carried out on the severely degraded lands of the Tibetan plateau. The grasslands created provide a useful model for evaluating the recovery of ecosystem properties. The purposes of this research were: (1) to examine the relative influence of various rehabilitation practices on carbon and nitrogen in plants and soils in early secondary succession; and (2) to evaluate the degree to which severely degraded grassland altered plant and soil properties relative to the non-disturbed native community. The results showed: (1) The aboveground tissue C and N content in the control were 105-97 g m(-2) and 3.356gm(-2), respectively. The aboveground tissue C content in the mixed seed treatment, the single seed treatment, the natural recovery treatment and the severely degraded treatment was 137 per cent, 98 per cent, 49 per cent and 38 per cent, respectively, of that in the control. The corresponding aboveground tissue N content was 109 per cent, 84 per cent, 60 per cent and 47 per cent, respectively, of that in the control. (2) Root C and N content in 0-20 cm depths of the control had an 2 2 average 1606 gm(-2) and 30-36 gm(-2) respectively. Root C and N content in the rehabilitation treatments were in the range of 26-36 per cent and 35-53 per cent, while those in the severely degraded treatment were only 17 per cent and 26 per cent of that in the control. (3) In the control the average soil C and N content at 0-20 cm was 11307 gm(-2) and 846 gm(-2), respectively. Soil C content in the uppermost 20 cm in the seeded treatments, the natural recovery treatment and the severely degraded treatment was 67 per cent, 73 per cent and 57 per cent, respectively, while soil N content in the uppermost 20cm was 72 per cent, 82 per cent and 79 per cent, respectively, of that in the control. The severely degraded land was a major C source. Restoring the severely degraded lands to perennial vegetation was an alternative approach to sequestering C in former degraded systems. N was a limiting factor in seeding grassland. It is necessary for sustainable utilization of seeding grassland to supply extra N fertilizer to the soil or to add legume species into the seed mix. Copyright (c) 2005 John Wiley & Sons, Ltd.

变形机器人倾翻稳定性仿真分析

凹凸不平的非结构环境中,移动机器人由于系统的倾翻将导致系统损害、作业失败等一系列问题。变形机器人可以通过构形的变化来提高系统的稳定性和抗倾翻能力。理论分析了移动机器人的倾翻问题,提出稳定锥方法和倾翻性能指数对移动机器人的静、动态稳定性进行综合判定,讨论了三模块履带机器人变形过程中的倾翻稳定性变化,同时仿真比较了机器人的五种能动构形在仰俯、偏转、倾斜等干扰组合作用下的倾翻性能。理论与仿真研究为变形机器人投入到实际应用提供了参考。

图像降噪复原算法及其应用

在图像成像、复制、扫描、传输、显示等过程中，不可避免地要造成图像的降质，如图像模糊、噪声干扰等。而在许多应用领域中，又需要清晰的、高质量的图像，因此，图像复原(如去噪、去模糊等)具有重要的意义。图像复原的目的是对降质图像进行处理，使其恢复成原始图像。它是图像处理、模式识别、机器视觉的基础，因而受到广泛的研究，并在天文学、遥感成像、医学影像等领域获得广泛的应用。图像复原的传统方法主要是进行图像滤波。由于图像的大部分信息存在于图像边缘部分，因此要求图像滤波既能去除图像的模糊和噪声，同时又能保持图像的细节。由于图像细节和噪声在频带上混叠，导致图像的平滑和边缘细节的保持成为一对矛盾。传统的滤波方法难以处理这类问题。近年来发展起来的偏微分方程图像处理技术，为解决图像复原中的这一矛盾提供了新途径。本论文共分五个部分。第一部分给出了图像复原的数学模型并讨论了其发展现状，综述了图像复原问题的规整化理论及方法，阐述了图像复原的基本过程和影响因素。第二部分研究了基于奇异值分解和能量最小原则的图像自适应降噪算法。基于有界变差的能量降噪模型的代数形式，提出了一种自适应图像降噪算法。该算法通过在矩阵范数意义下求能量最小，自适应确定去噪图像重构的奇异值个数。这一算法的特点是将能量最小原则和奇异值分解结合起来，在代数空间中建立了一种自适应的图像降噪算法。与基于压缩比和奇异值分解的降噪方法相比，该算法避免了图像压缩比函数及其拐点的计算。因此求解更加简单。第三部分研究了基于各向异性扩散的图像降噪和抖动消除算法。提出了两种算法，一、提出了一个由各向异性扩散方程定义的非线性图像滤波算子。与Perona，Malik提出的算子类似，该算子能够去除噪声，而且性能稳定，处理后的自然图像看上去清晰而且对比度也得到增强。对于图像抖动产生偏移，二、提出了一种基于各向异性非线性扩散以及抖动估计的抖动消除算法。这种各向异性非线性扩散的模型由两项组成，即扩散项以及强制项。基本思想就是对于边缘点以及光滑区域的点分别进行处理，利用Newton-Raphson算法计算最小化抖动误差，估计出抖动偏移量，从而得到抖动消除之后的图像。第四部分研究了基于四阶偏微分方程和基于高斯曲率的图像降噪算法。针对低阶的非线性偏微分方程进行图像去噪，如总变差、平均曲率流等去噪模型，会产生阶梯效应这一缺陷，即易得到分段常量结果的缺陷，提出了一种基于四阶偏微分方程的图像降噪算法，并给出了实验结果。提出了一种改进的基于高斯曲率和偏微分方程的图像降噪算法。该算法能够得到一个稳态的非平凡解，从而能够避免中止时间的选取。第五部分研究了基于C-V降噪模型的图像半盲复原算法。基于C-V降噪模型，提出了一种图像半盲的复原算法，即假定图像退化的模型已知，如高斯模糊，但是高斯核的方差未知，通过构造能量函数，将能量函数的极小问题转化为一个变分极小问题，由变分原理得到相应的欧拉-拉格朗日方程。这里设计的算法将未知数的个数由Leah Bar模型的三个减少为两个，最后估计出来高斯核的方差比Leah Bar 算法更加接近于真值。

硼及其同位素对水体污染物的示踪研究

硼的易溶性和硼化合物的广泛使用，以及污水处理过程中除硼的困难，最终导致地表地下水 体富集硼及有关污染物。海滨地下水受到海水入侵，硼含量及p(B)／p(C1)比值发生明显变化。混 合、吸附、水一岩等作用使得硼同位素发生分馏，显著区别于区域背景值。因此，结合其它同位素、水化 学等信息，硼及其同位素作为良好示踪剂为研究水圈中物质的地球化学循环过程提供了新的手段。 文中总结了部分天然水体的硼含量和硼同位素组成特征，综述了近年来用硼同位素示踪水体的污染 物来源、程度和范围等方面新的研究成果。

^137Cs在滇西与黔中地区散落的差异—青藏隆起对滇西地区全球性扩散大气污染物散落屏蔽效应的推断

云贵高原是青藏隆起在南亚大陆形成的一个海拔梯度大、地势格局复杂的特异环境单元。该地域兼受东南季风与西南季风的交汇影响，是全球变化的敏感区之一。青藏隆起对云贵高原现代环境影响主要表现在：1）全球性大气扩散污染物的屏蔽效应和局地性大气扩散污染物的滞留效应；2）区域化学风化的增强效应和物理侵蚀的梯级效应；3）地表环境地球化学过程的低纬度－高海拔效应。核素示踪模式分析表明：滇西与黔中地区之间^137Cs自大气散落差异明显[1986年以前，洱海和红枫湖沉积物中^137Cs散落的累计值分别为（0．11±0．01）Bq/cm^2及（0．37±0．01）Bq/cm^2],而^7Be的散落相近。这说明青藏隆起对滇西地区存在全球性扩散大气污染物散落的屏敝效应。