抚育间伐对人工林土壤肥力的影响

研究了杉木、马尾松、建柏、柳杉和木荷人工林的抚育间伐对林分土壤肥力的影响.结果表明,杉木、马尾松、建柏、柳杉、木荷间伐后降低了林分的郁闭度.改变了林内的生境条件,促进了林下乡土植被的生长和繁衍,林下植被覆盖度、植被生物量和物种丰富度有了较大幅度的增加,间伐的强度越大.增加的幅度也越大.与不间伐林分相比,各间伐林分两年后土壤微生物数量增加、酶活性增强、土壤容重降低、总孔隙度和速效养分提高,土壤肥力得到了改善和提高.间伐后林分土壤肥力得到提高的实质在于:间伐后林下植被生物多样性的提高诱发了土壤微生物多样性和数量的提高,并由此而增强了土壤的生物活性,加速了土壤养分的循环.     

我国蓝藻水华的发生机理、危害及防控利用研究进展

近些年蓝藻水华的大规模爆发不仅危害了水产养殖业,而且严重影响了人类日常生活、供水、旅游业等。主要介绍了蓝藻水华爆发的内在因素（假空泡、类胡萝卜素、厚壁孢子、细胞壁等）及外在因素（营养物质、温度、微量元素、滤食性鱼类等）。阐述了蓝藻水华对生产、生态和生活造成的危害,归纳总结了蓝藻水华防控的化学、物理、生物等方法。最后描述了蓝藻水华的有效利用并提出其研究中存在的问题。     

改良型抗菌肽的研究进展

长期滥用抗生素导致了耐药菌株“超级细菌”的出现,增加了动物、人类健康和环境污染风险．寻找抗生素替代品正成为全球研究热点,抗菌肽因其高效抗菌效果和不同于抗生素的独特作用机制引起了各国研究者的关注,并进行了相关研究．然而抗菌肽的安全性、稳定性、生产成本等问题限制了其生产与应用．为了克服这些不利因素,研究者们对抗菌肽进行了多种方式的改造,产生了模拟型、同源型、杂合型、轭合型、稳定型和固位型等改良型抗菌肽,并有望在畜牧业、食品业、医药业等领域得到广泛的应用．本文主要综述了这些改良型抗菌肽近年来的研究进展．     

主要农作物转基因研究现状和展望

近15年来,大豆、水稻、玉米、小麦等主要农作物转基因研究取得了较大进展,几乎各种遗传转化方法在这些作物上都取得了成功,尤其是农杆菌介导法,不仅在难转化的双子叶作物大豆上取得了成功,而且在单子叶作物水稻、玉米、小麦上先后取得了突破。同时,将一些与重要性状改良有关的外源基因转入了主要农作物,包括抗虫、抗病、抗除草剂、抗逆、品质改良、发育调控、营养吸收等。转基因大豆、玉米、棉花、油菜在生产上得到了大面积种植,产生了极大的经济效益,2004年全球转基因作物的种植面积达到了8100万公顷。本文对大豆、玉米、水稻和小麦等主要农作物转基因研究历史和产业化现状进行了综述,并对主要农作物转基因研究中存在的问题进行了分析。     

中科院水生所开发名优水产健康高效养殖技术

近日,由中国科学院水生生物研究所、华中农业大学、长江大学等单位承担的湖北省“十五”科技攻关计划重大项目“名优水产品健康高效养殖技术研究及产业化开发”通过了湖北省科技厅组织的专家组验收。科研人员系统地研究了黄鳝、长吻能、黄颡鱼、鳜鱼和青虾的繁殖、营养、养殖等关键技术;合理评估了鳜鱼、河蟹和青虾的养殖容量和生态效应,提出了鳜鱼的湖泊放养措施和管理模式;完成了中华鳖的快速培育技术和大水面的无公害养殖生产技术。建立了健康、     

景观可视化及其应用

介绍了景观可视化的概念,回顾了景观可视化的发展历程,然后介绍了景观要素,包括地形、植被、水、人工构件(建筑物、基础设施等)、动物(包括人)、大气和光的可视化表达方法,阐述了景观可视化在景观规划、景观变化、气候变化、城市景观、景观视觉影响评价和森林管理等方面的应用,最后提出了景观可视化的未来发展趋势.     

龙眼树形对生长结果及机理影响初探

为了解决龙眼园的郁闭问题,提高龙眼的产量和品质,该文以桂香龙眼品种为材料,研究了扁开心形、开心形、自然圆头形三种不同树体结构对树体光照强度、叶片、根系、果实的影响。结果表明:扁开心形显著改善了树冠和果园通风透光环境,提高了叶绿素含量,增大了叶面积,提高了PSⅡ系统活性和开放程度,调节了光合机构的自我保护机制,改善了荧光参数,从而提高了果实品质;扁开心形、开心形、对照的单株产量分别是19.90、17.00、15.60 kg,单果重分别是10.24、10.07、7.64 g;扁开心形和开心形可食率比对照分别提高了4.20%、4.40%,可溶性固形物含量分别提高了12.16%、12.55%;扁开心形比开心形以及对照的表层根有所上浮,促进了果树的生殖生长,显著扩大了根系的分布深度,扩大了根系对营养物质以及水分的吸收。扁开心形是一种高光效的树形,应在生产上加以推广。     

陕西省植物引种驯化的回顾与展望

回顾了陕西植物引种驯化的成就、经验,特别是对区域性的引进种类、成功事例进行了较详尽的叙述,并在此基础上讨论了引种驯化的理论、方法与技术措施、路线,展望了陕西植物引种驯化的趋向,提出了若干建议。     

加工工艺因素对黑蒜营养素与功效成分的影响

综述了黑蒜中的水分、蛋白质、氨基酸、糖类、5-羟甲基糠醛、酚类、黄酮类、生物碱、阿霍烯等营养成分和功效,介绍了时间、预处理、温度等工艺因素对上述成分的影响,为黑蒜的生产工艺优化与品质研究提供了参考。     

山西省干旱地区农作物种质资源普查与分析

本研究对山西省干旱地区右玉县、阳曲县、隰县、临县、石楼县、繁峙县、灵丘县、五台县、浑源县、武乡县、五寨县和兴县12个县的农作物种质资源进行了普查和数据分析。通过查阅文献和实地调查相结合的方法,完成了12个县农作物种质资源普查表的编制,分析了1981年到2010年30年来普查县气候及植被变化趋势,并阐述了普查县大宗农作物种植面积、产量和大面积种植品种的变化情况,在此基础上提出了农作物种质资源保护面临的问题及对策建议。研究结果为干旱地区农作物种质资源的保护、研究和利用提供了参考。     

环境变异对青稞热稳定蛋白质含量及蛋白质Z的影响

热稳定蛋白是衡量麦芽品质的重要指标,为探明青稞籽粒和麦芽热稳定蛋白的含量、蛋白质Z的组成特征以及影响条件。本研究以3份青稞和1份对照大麦品种Gairdner为试验材料,对青稞籽粒及其麦芽的热稳定蛋白进行分析与鉴定,研究了不同生态环境下青稞热稳定蛋白质含量和蛋白质Z的组成特征,同时筛选出了优异啤用品质青稞品种(品系)。结果表明,青稞发芽温度为20℃,发芽时间为72 h,培养溶液PH为5时,发芽及焙焦条件下最有利于青稞热稳定蛋白总含量及蛋白质Z的累积。利用该发芽条件筛选种植于西宁、湟源和海晏的青稞资源,发现种植于西宁的青稞种子和发芽后热稳定蛋白质总含量最低,但是焙焦后热稳定蛋白质和蛋白质Z含量最高;同时从150份青稞资源中筛选出热稳定蛋白质含量及蛋白质Z条带清晰、含量高的优异资源15份。本研究结果为酿造青稞品种选育、啤用青稞和麦芽质量评价指标提供理论依据。     

~(60)Co-γ射线诱发皖麦50 Glu-1A亚基等位基因突变体差异蛋白质组学研究

研究了皖麦50及~(60)Co-γ射线诱发的Glu-1A突变体的比较蛋白质组学,结果表明,突变体蛋白质含量增加,2-D电泳图上有11个蛋白质斑点表达差异显著,其中3个蛋白点上调,8个蛋白点下调。经MALDI-TOF/TOF质谱鉴定,差异蛋白点涉及44个蛋白质。通过GO分析,参与生物过程的差异蛋白中,18个蛋白质参与代谢过程,18个蛋白质参与细胞过程,8个蛋白质参与刺激响应。参与分子功能差异蛋白中,18个蛋白质参与催化活性,10个蛋白质参与链结,7个肽段为分子功能调解剂,9个肽段为未知蛋白。参与细胞成分的差异蛋白中,12个蛋白质为胞外区蛋白,12个蛋白质为细胞,9个蛋白质为细胞器,2个蛋白质为膜,9个蛋白质为未知蛋白。KEGG通路注解表明,差异蛋白质中,4个蛋白质参与淀粉和蔗糖代谢,3个蛋白质参与氨基糖和核苷酸糖代谢,1个参与丙酮循环,1个参与半胱氨酸和甲硫氨酸代谢,1个参与丙酮酸代谢,1个参与乙醛酸和二羧酸代谢,1个参与光合生物碳固定,1个参与碳代谢信息通路。     

链球菌蛋白G的构建、重组表达及鉴定

化学合成链球茵蛋白G的C3D基因片段,通过分子生物学的方法对蛋白G（proteinG）的C3片段进行PCR扩增,拼接形成含有两个和三个重复C3片段的重组链球茵蛋白G,C3片段间以链接区D连接,即形成C3DC3和C3DC3DC3的形式,进而克隆到质粒pET21中,在大肠杆菌BL21（DE3）中表达。重组表达的蛋白经过DEAE—Sepharose和IgG—Sepharose纯化,得到纯化的重组蛋白。采用非竞争性酶免疫法对重组蛋白与不同来源IgG的结合常数进行测定,实验结果显示两种重组链球茵蛋白G均可有效地与小鼠、兔及山羊等多种不同来源抗体特异性结合。这些实验结果为下一步研究奠定了基础。     

Reactivation of Partially Metallocluster-deficient MoFe Protein by Chromium-Containing Reconstituent Solution

By treating the reduced MoFe protein from Azotobacter vinelandii with o-phenanthroIi e and O2, partially deficient in both FeMoco and P-cluster and inactive protein could be o rained. After incubating the treated protein with a reconstituent solution containing K2CrO4, ferric homocitrate, Na2S and dithiothreitol, a reactivated protein could be obtained. The absorption spectrum, circular dichroism spectrum, and the C2H2 and proton reduction activities of the reactivated protein were remarkably recovered. However, the spectra were somewhat different from those of the reduced MoFe protein. The results showed that some of the reactivated protein might be Cr-containing protein (CrFe protein) which were similar in function, but somewhat different in structure from MoFe protein.     

The Effect of Manganese on the Reconstitution of Partial Metallocluster-deficient Nitrogenase Molybdenum-Iron Protein

By treating the reduced MoFe protein of nitrogenase from Azotobacter vinelandii with O-phenanthroline (O-phen) and O2, inactive MoFe protein which was partialy deficient in both P-cluster and FeMoco could be obtained. After incubating the inactive protein with a reconstituent solution containing KMnO4, ferric homocitrate, Na2S and dithiothreitol, a reconstituted protein could be obtained. The absorption spectrum and C2H2, H+ and N2 reduction activity of the reconstituted protein could be well restored to the state of the reduced MoFe protein. However, the α-helix and CD spectrum at 380—550 nm and at 620—670 nm of the reconstituted protein were somewhat different from those of the reduced MoFe protein. The results showed that: (1) the reconstituted protein was composed of the assembled protein which might be a MnFe protein due to the reconstitution of the metalloclusterdeficient MoFe protein with Mn-containing solution and MoFe protein in which metalloclusters were still intact after the treatment with O-phen and O2; (2) It might be possible that the MnFe protein and MoFe protein were similar in the ability of nitrogen fixation, but were somewhat different in the structure from each other.     

含铬重组液激活部分缺失金属原子簇的钼铁蛋白的研究

棕色固氮菌（Ａｚｏｔｏｂａｃｔｅｒ ｖｉｎｅｌａｎｄｉｉ）固氮酶钼铁蛋白经邻菲口罗啉和Ｏ２ 处理后,变为部分缺失ＦｅＭｏｃｏ 和Ｐ－ｃｌｕｓｔｅｒ的失活蛋白。与由Ｋ２ＣｒＯ４、高柠檬酸铁、Ｎａ２Ｓ和二硫苏糖醇组成的重组液保温后,处理蛋白对乙炔和质子还原的活性都得以显著恢复;然而,它的吸收光谱和圆二色谱虽有明显恢复,但仍与还原钼铁蛋白有所不同。这表明,激活蛋白中也许存在功能与钼铁蛋白相似,而结构则有所差异的含铬（ＣｒＦｅ）蛋白     

Hydrolysis of lipid and protein reserves in loblolly pine seeds in relation to protein electrophoretic patterns following imbibition

The correlation between changes in seed protein electrophoretic patterns and the hydrolysis of lipid and protein reserves of loblolly pine ( Pinus taeda L.) seed was studied. Seeds were incubated at 30°C for up to 12 days following stratification, then megagametophytes and embryos were assayed for lipid and protein content after each day of imbibition. The megagametophyte of mature seed was found to contain 20% lipid and 12% storage protein on a fresh weight basis. The embryo contained 26% lipid and 15% protein. Both lipid and protein reserves were depleted constantly following imbibition. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of soluble and insoluble protein fractions showed a 60 kDa protein that was representative of crystalloid-like proteins. These crystalloid-like proteins comprised 85% of the insoluble protein storage reserves. A small number of insoluble storage proteins, including a 47 kDa protein, were distinct in that they were unaffected by 2-mercaptoethanol treatment. The soluble fractions from both tissues were labelled with [³⁵S]-methionine, and incorporation was visualized by two-dimensional electrophoresis. Proteins were found to belong to one of three categories, those synthesized constitutively (comprising the bulk of newly synthesized proteins), those synthesized during germination or those synthesized after radicle emergence. Accompanying seed reserve hydrolysis were developmental shifts in protein pattern and synthesis, suggesting the possibility that control of hydrolysis is at the level of enzyme accumulation.     

Energy and protein requirements of Belgian Blue double-muscled bulls

Energy and protein requirements were determined for Belgian Blue double-muscled (BB dm) bulls based on the results of two feeding trials and a trial with serial slaughtering. The results of the serial slaughter experiment allowed calculation of chemical composition and energy content of the empty body, as well as protein and energy deposition at various live weights between 350 and 650 kg. Protein requirements were calculated based on the protein requirements for maintenance, the protein mass accreted and the efficiency of protein accretion. Efficiency of protein deposition (g protein accretion/g protein intake for accretion) was derived from the feeding experiments based on marginal protein levels; it decreased from 0.53 to 0.44 with increasing live weight. Energy requirements were also derived from the same database. Net energy for maintenance was estimated, with these animals that received an optimum energy/protein ratio, by subtracting the net energy retained from the net energy intake. Requirements were then determined by summation of the energy requirements for maintenance and the energy requirements for accretion. Conclusively, energy and protein requirements were determined for BB dm bulls for live weights from 350 to 650 kg and for different growth rates. As such, surpluses of energy and protein that BB dm animals require compared to other beef breeds, were quantified.     

基于序列特征网络的蛋白质结构类型研究

利用复杂网络的方法来探索序列特征因素对蛋白质结构的影响。由于蛋白质的序列对结构具有重要且复杂的影响,因此将蛋白质的结构以及序列特征之间的关系模拟成一个复杂系统,通过利用互相关系数、标准化互信息和传递熵等方法来建立以序列特征为节点的加权网络,进而利用网络中心性的方法来分析不同蛋白质结构类型对应加权网络的中心性分布的差异,探索不同结构类型蛋白质的序列特征差异。发现不同的蛋白质结构类型对应的序列特征网络既有共性又有差异,文章将针对每一种结构类型的网络中心性分布,以及不同结构类型之间的共性与差异进行详细地讨论。研究结果对蛋白质序列与结构之间关系的研究,特别是结构分类研究具有重要的意义。