分子运动性预测顽拗性种子麻栎离体胚轴适宜贮藏条件初探

顽拗性种子在分类上分布广泛。由于顽拗性种子贮藏特性极为特殊，对脱水和低温均十分敏感，易受损伤，所以种子寿命很短，因此在植物种质资源保存领域，顽拗性种子的保存一直被列为重点研究课题，至今仍难以找到顽拗性种子的适宜贮藏条件，或该类种子保存通行的方法，仅推测长期保存顽拗性种子种质资源最有前途的方式是超低温保存，顽拗性种子资源保存是一个世界性难题。 本文试图使用分子运动性预测顽拗性种子离体胚轴的适宜贮藏条件。选用壳斗科植物麻栎种子为实验材料。应用电子顺磁共振波谱仪和自旋标记技术，以硝基氧探针CP为标记物，检测到室温下麻栎种子离体胚轴脱水过程中分子运动性的变化。含水量0.7 g H2O/g DW至0.64 g H2O/g DW范围是细胞质粘度的转折区域，低于这个含水量区域，细胞质粘度骤然上升，推测这个区域是室温下保存离体胚轴的适宜含水量下限。 通过变温电子顺磁测定，找到离体胚轴含水量在0.43 g H2O/g DW至1.02 g H2O/g DW范围内，分子运动性的临界温度和玻璃态相变温度所在区间。根据分子运动性随温度变化规律，预测含水量为0.69 g H2O/g DW的麻栎种子离体胚轴适宜贮藏温度约为-50 ℃。 根据EPR实验结果，将胚轴脱水，并根据实验条件选择不同温度进行低温贮藏验证实验，应用颜色观测法和TTC存活力鉴定法，初步验证分子运动性理论可以应用在顽拗性种子离体胚轴的低温贮藏研究中。 本研究说明顽拗性种子资源的保存有可能通过离体胚轴的低温贮藏实现，用分子运动性预测低温贮藏的适宜条件，很可能为上述问题的解决提供了有效的技术参数。

Feeding metabolism in an Indian major carp (Catla catla Lin.) fed on different protein diets

Feeding metabolism in an Indian major carp, Catla catla fingerlings of 10.8+0.56g was investigated in a flow-through water recirculating system. The metabolic energy loss in resting metabolism and feeding metabolism were determined by the indirect method of oxygen consumption followed by multiplication by suitable oxycalorific coefficient. This was done in four metabolic chambers of a respirometer system. Ten fish fingerlings of mean total weight of 109.5, 110.4 and 112.8g/chambers respectively each in two experimental runs of three treatments a, b and c were used. The mean resting metabolic rate during unfed condition showed no significant variation in different treatments. The fish in three treatments a, b and c fed on diets containing 28, 33 and 38% crude protein had significantly different (p<0.05) post-fed SDA magnitude of 497.7, 638.7 and 735.5 mgO2/chamber/day having an equivalent energy loss of 12.68, 14.68 and 15.86 KJ respectively. The SDA co-efficient in three treatments a, b and c were 14.95, 19.00 and 22.36% respectively whereas, respiratory energy - 'R' as % of mean total ingested energy in three treatments were 26.93, 31.17 and 34.74% respectively showing a significant increase (p<0.05) with increase of protein. Feeding metabolism in an Indian major carp (Catla catla Lin.) fed on different protein diets.

磷脂酰甘油对光系统I的调控作用

磷脂酰甘油(PG)是光系统I(PSI)中唯一的磷脂，也是PSI重要的组成部分。在本工作中，我们通过改变PSI中PG的含量(体外重组至PG脂质体或专一性磷脂酶降解)，研究了PG对PSI的调控作用。主要结果如下： 1. 外加PG导致PSI色素的结合状态和激子相互作用发生改变。吸收光谱中，Chl a特征峰蓝移且吸收降低。低温荧光光谱中，680nm处的峰逐渐明显，F730-735 /F680的比值下降，LHCI-730激发峰蓝移。可视CD光谱中Chl a、Chl b蓝移，它们的相互作用增强;类胡萝卜素分子发生红移。 2. PSI的重组引起了PSI蛋白质结构的改变，即蛋白的α-螺旋结构增加而无序结构含量减少。同时，PSI蛋白质内部的色氨酸残基处于更极性的环境。 3. PG对PSI的电子传递的影响具有浓度效应。低浓度时可以促进PSI的电子传递活性，而在相对较高浓度时抑制PSI的电子传递。 4. PLA2的处理导致PSI中PG的缺失，抑制了PSI反应中心P700的暗还原反应，即延长了其还原所用的时间。P700的暗还原反应存在快相和慢相两相反应。PG的缺失降低了这两相反应的反应速率，抑制了电子从质体蓝素(PC)到P700+的传递。

Enhanced flexoelectric switching behaviour in the chiral nematic phase

In order to develop materials that exhibit enhanced flexoelectric switching in the chiral nematic phase we have identified mesogenic units that display inherently strong flexoelectric coupling capabilities. Here we examine the oxycyanobiphenyl (OCB) moiety: homologues from the nOCB series exhibit significant electro-optic switching effects when doped with a highly chiral additive. Here we have examined lower dielectric anisotropy materials, since they allow the flexoelectric response to be extended to high field amplitudes. We show that dielectric coupling strength can be low in symmetric bimesogenic molecules. The flexoelectric response of such a molecular structure is tested by doping a homologue from the series CBOnOCB with a chiral additive: very significantly we find that the optic axis is rotated through 2φ=45° in <50 μs on reversing the polarity of the field (amplitude E=±6 V μm-1). Subsequently we have synthesized room temperature chiral nematic materials that exhibit 2φ≥90° at E≈10 V μm-1. © 2001 OPA (Overseas Publishers Association) N.V. Published by license under the Gordon and Breach Science Publishers imprint, a member of the Taylor & Francis Group.

一种天然海藻内生真菌二萜生物碱类化合物及其制备和应用

本发明涉及细菌抑制剂领域，具体地说是一种天然的海藻内生真菌二萜生物碱类化合物及其制备和应用。具体结构式如（I）所示，其制备方法为将米曲霉（Aspergillus oryzae）cf-2接种于培养基中静止发酵，发酵液经乙酸乙酯萃取浓缩，菌丝体先用有机溶剂提取，再经乙酸乙酯萃取浓缩，合并浓缩物，得到粗提物；粗提物进行硅胶柱层析，用有机溶剂进行梯度洗脱，收集洗脱液，洗脱液经薄层层析检测；将以洗脱液体积比0-10：100梯度，洗脱下的组分进行凝胶柱层析、硅胶柱层析和薄层层析分离纯化得目标化合物。本发明所得二萜生物碱类化合物具有显著的抑菌活性。

黄河口滨岸潮滩湿地系统氮生物循环特征与循环模式研究

潮滩湿地处于海陆相互作用地带，是响应全球变化和人类活动较为敏感的生态系统 之一。潮滩湿地是海岸带一个非常重要的生态类型，作为陆地和海洋过渡区的重要组成 部分，承接来自陆地人类活动带来的大量含氮物质。潮滩湿地氮的生物循环特征不但影 响湿地系统自身的调节机制，而且其在环境介质中的特殊动力学过程也与一系列全球环 境问题息息相关。为了更深入的理解潮滩湿地氮的生物循环特征及其关键机制，论文以 黄河口滨岸潮滩翅碱蓬湿地为研究对象，通过野外样品采集、原位实验、微区试验，研 究了湿地土壤氮的时空分布与化学转化特征，探讨了湿地植物生物量与氮累积季节变化 特征以及湿地植物残体分解及分解过程氮动态特征，建立了湿地植物-土壤系统氮循环 分室模式，主要结论如下：（1）潮滩湿地土壤氮含量具有明显的水平变异和空间结构， TN、NO3 --N 和C/N 具有明显空间分布格局，其空间变异性均以向低潮滩延伸且受潮汐 涨落影响较大的方向最大；微地貌特征和潮汐微域物理扰动是导致空间异质性的两个重 要随机因素，水盐条件、土壤类型和潮汐物理扰动是三个重要结构因素；（2）潮滩湿地 土壤氮含量在不同时期的垂直分布均存在较高变异性，主要与有机质分布、潮汐影响、 水分条件以及陆源影响程度有关；潮滩湿地土壤的氮含量具有明显季节变化特征，主要 与水分状况及受潮汐影响的程度有关；（3）潮滩湿地土壤氮的净矿化/硝化速率均呈波动 变化，并受生物固持、反硝化、温度、水分、C/N 和pH 等因素影响；潮滩湿地0~15cm 土壤的净矿化量和净硝化量分别介于0.33~27.81kg·hm-2 和1.19~15.99kg·hm-2，高潮滩湿 地维持无机氮的能力明显强于中潮滩和低潮滩湿地；（4）两种表现型翅碱蓬的生物量 均具有明显季节变化和空间结构分形特征，二者的地上生物量具有自相似性，分别遵从 D=2.012 和2.366 的分形生长过程；（5）沉积强度显著影响翅碱蓬种子的出苗和幼苗存 活，适度沉积可刺激幼苗生长，重度沉积对幼苗生长则具有抑制作用；沉积可促使幼苗 被埋部分发育为根系，反映了其对潮滩较强沉积环境的特殊适应对策；（6）两种表现 型翅碱蓬根、茎和枯落物的TN 含量均呈递减变化，符合指数衰减模型，叶是二者重要 氮储库，分配比高达46.91±16.97%和55.21±9.79%；中潮滩植被的N/P 为9.87±3.47＜14， 其生长受N 限制，低潮滩植被的N/P 为15.73±5.00＜16，其生长同时受N、P 限制，但 更受P 限制；（7）潮滩湿地植物残体在水盐含量较高或沉积较强条件下的失重率和分解 速率一般较高，反之则较低；温度、水分、盐分和pH 是影响残体相对分解速率的重要 摘 要 II 因素；（8）当分解环境的养分状况不发生较大改变时，残体相对分解速率在很大程度上 取决于基质质量，当养分状况因潮汐养分交换、潮汐物理扰动、沉积物矿化等发生较大 改变时，残体相对分解速率在很大程度上取决于分解环境养分供给状况；（9）潮滩湿地 植物残体在不同水盐梯度和沉积强度下的氮含量、C/N 的变化模式整体较为一致，水盐 条件和沉积强度对残体氮绝对量的变化具有重要影响，C/N 对分解过程中氮养分的调控 作用更为重要；（

Study on the critical submergence of surface vortices and the design of anti-vortex intakes

Surface vortex behavior in front of the tunnel intake was investigated in this paper. The critical submergence of vortex was discussed based on the concept of 'critical spherical sink surface' (CSSS). The vortex formation and evolution at the tunnel intake were analyzed based on the theory of CSSS considering the effect of circulation. A theory was proposed to explain the surface vortex. The theoretical development was verified by the physical model experiments of Xiluodu hydropower station. The radial velocity and vortex circulation were considered as the main factors that influence the formation and evolution of surface vortex. Finally, an anti-vortex intake configuration was proposed to weaken the air-core vortex in front of the tunnel intakes of the hydraulic structures. © 2011 Science China Press and Springer-Verlag Berlin Heidelberg.

Modelling the long-term sustainability of indigenous hunting in Manu National Park, Peru: landscape-scale management implications for Amazonia

P> Widespread hunting throughout Amazonia threatens the persistence of large primates and other vertebrates. Most studies have used models of limited validity and restricted spatial and temporal scales to assess the sustainability. We use human-demographi

Wavelength-tuneable liquid crystal lasers from the visible to the near-infrared

The study of band-edge lasing from dye-doped chiral nematic liquid crystals has thus far been largely restricted to visible wavelengths. In this paper, a wide range of commercially available laser dyes are examined for their suitability as infrared emitters within a chiral nematic host. Problems such as poor solubility and reduced quantum efficiencies are overcome, and successful band-edge lasing is demonstrated within the range of 735-850 nm, using the dyes LD800, HITC-P and DOTC-P. This paper also reports on progress towards widely tuneable liquid crystal lasers, capable of emission in the region 460- 850 nm. Key to this is the use of common pump source, capable of simultaneously exciting all of the dyes (both infrared and visible) that are present within the system. Towards this aim, we successfully demonstrate near-infrared lasing (800 nm) facilitated by Förster energy transfer between the visible dye DCM, and the infra-red dye LD800, enabling pump wavelengths anywhere between 420 and 532 nm to be used. These results demonstrate that small and low-cost tuneable visible to near-infrared laser sources are achievable, using a single common pump source. Such devices are envisaged to have wide-ranging applications including medical imaging (including optical coherence tomography), point-of-care optical medical diagnostics (such as flow cytometry), telecommunications, and optical signatures for security coatings. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

鹿属动物线粒体DNA序列测定的研究

对9种鹿属动物的线粒体DNA进行引物扩增和序列测定,并与牛科、马科的DNA序列进行比较。找到了鹿属动物特异的DNA序列。利用该序列可对鹿类药材进行真伪区分。

Mitochondrial diversity and phylogeographic structure of Chinese domestic goats

China has numerous native domestic goat breeds, but so far there has been no extensive study on genetic diversity, population demographic history, and origin of Chinese goats. Here, we examined the genetic diversity and phylogeographic structure of Chinese domestic goats by determining a 481-bp fragment of the first hypervariable region of mitochondrial DNA (mtDNA) control region from 368 individuals representing 18 indigenous breeds. Phylogenetic analyses revealed that there were four mtDNA lineages (A-D) identified in Chinese goats, in which lineage A was predominant, lineage B was moderate, and lineages C and D were at low frequency. These results further support the multiple maternal origins of domestic goats. The pattern of genetic variation in goat mtDNA sequences indicated that the two larger lineages A and B had undergone population expansion events. In a combined analysis of previously reported sequences and our sequences belonging to lineage B, we detected two subclades, in which one was unique to eastern Asia and another was shared between eastern and southern Asia. A larger genetic variation in eastern Asia than southern Asia and the pattern of phylogeographic variation in lineage B suggest that at least one subclade of lineage B originated from eastern Asia. There was no significant geographical structuring in Chinese goat populations, which suggested that there existed strong gene flow among goat populations caused by extensive transportation of goats in history. (c) 2005 Elsevier Inc. All rights reserved.

Polymerase chain reaction based C4AQ0 and C4BQ0 genotyping: association with systemic lupus erythematosus in southwest Han Chinese

Objective: To investigate the association of complement C4 null genes (C4QO, including C4AQO and C4BQO) and C2 gene with systemic lupus erythematosus (SLE) in southwest Han Chinese; 136 patients with SLE and 174 matched controls were genotyped. Methods: C4 null genes were determined by a polymerase chain reaction (PCR) procedure with sequence specific primers (PCR-SSP). The 2 bp insertion in exon 29, which was previously identified in non-Chinese populations and caused defective C4A genes, was directly typed by sequencing the whole exon 29 using exon specific primers. The exon 6 of complement C2 was also sequenced in both the patients and controls. Results: The frequency of homozygous C4AQO allele was 12.5% (17/136) in patients with SLE compared with 1.1% (2/174) in controls (p<0.001, odds ratio (OR)=12.286, 95% confidence interval (95% CI) 2.786 to 54.170). There was no significant difference for homozygous C4BQO allele between patients with SLE and controls (p=0.699). Patients with the C4AQO gene had an increased risk of acquiring renal disorder, serositis, and anti-dsDNA antibodies compared with those without C4AQO (for renal disorder, p=0.018, OR=8.951, 95% Cl 1.132 to 70.804; for serositis, p=0.011, OR 4.891, 95% CI 1.574 to 15.198; for anti-dsDNA, p=0.004, OR 7.630, 95%Cl 1.636 to 35.584). None of the patients or controls had the 2 bp insertion in exon 29 of the C4 gene. The type I C2 deficiency was not detected in the 3 10 samples. Conclusion: It is suggested that deficiency of C4A (not due to a 2 bp insertion in exon 29), but not C4B or C2, may be a risk factor for acquiring SLE in south west Han Chinese; this results in increased risk of renal disorder, serositis, and anti-dsDNA antibodies in patients with SLE. Racial differences seem to be relevant in susceptibility to SLE.