基于遥感和GIS的川西绿被时空变化研究

探索出了利用多时相MODIS数据分析绿被时空变化的技术方法,揭示出了川西2002—2008年间绿被的变化特征。建立了绿被提取模型。用其从2002—2008年的多期MODIS影像中提取出川西多期绿被数据。其次,利用GIS技术对2002—2008年间绿被变化,及其与温度、降雨的关系等进行了分析。研究表明:2002年绿被天数在195 d以上的区域有43.3%。终年无绿被的区域有4.3%。西北部植被生长日数短,而东南部生长日数长。2002—2008年间,春季绿被面积变幅最大,秋季最小。最大绿被面积出现在2006年的夏季,最小绿被面积出现在2005年的冬季。平均夏冬绿被面积差占区域面积46.7%。在季节上,绿被面积与温度和降雨量均在0.01的水平上呈显著正相关关系,其相关系数分别为0.82和0.84。该研究成果对植被生长潜力挖掘、农牧生产和生态建设决策等均有重要意义。     

Protein kinase C delta null mice exhibit structural alterations in articular surface,intra-articular and subchondral compartments

IntroductionStructural alterations in intra-articular and subchondral compartments are hallmarks of osteoarthritis, a degenerative disease that causes pain and disability in the aging population. Protein kinase C delta (PKC-δ) plays versatile functions in cell growth and differentiation, but its role in the articular cartilage and subchondral bone is not known.MethodsHistological analysis including alcian blue, safranin O staining and fluorochrome labeling were used to reveal structural alterations at the articular cartilage surface and bone–cartilage interface in PKC-δ knockout (KO) mice. The morphology and organization of chondrocytes were studied using confocal microscopy. Glycosaminoglycan content was studied by micromass culture of chondrocytes of PKC-δ KO mice.ResultsWe uncovered atypical structural demarcation between articular cartilage and subchondral bone of PKC-δ KO mice. Histology analyses revealed a thickening of the articular cartilage and calcified bone–cartilage interface, and decreased safranin O staining accompanied by an increase in the number of hypertrophic chondrocytes in the articular cartilage of PKC-δ KO mice. Interestingly, loss of demarcation between articular cartilage and bone was concomitant with irregular chondrocyte morphology and arrangement. Consistently, in vivo calcein labeling assay showed an increased intensity of calcein labeling in the interface of the growth plate and metaphysis in PKC-δ KO mice. Furthermore, in vitro culture of chondrocyte micromass showed a decreased alcian blue staining of chondrocyte micromass in the PKC-δ KO mice, indicative of a reduced level of glycosaminoglycan production.ConclusionsOur data imply a role for PKC-δ in the osteochondral plasticity of the interface between articular cartilage and the osteochondral junction.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0720-4) contains supplementary material, which is available to authorized users.     

Kosteletzkya virginica, a halophytic species with potential for agroecotechnology in Jiangsu Province, China

Kosteletzkya virginica (L.) Presl. is a perennial dicot halophytic species, that grows in brackish portions of coastal tidal marshes of the mid-Atlantic and southeastern United States. New saline mudflats have been increasing every year in Northern Jiangsu, China. In 1993, we introduced K. virginica (L.) into China from the Halophyte Biotechnology Center (University of Delaware, USA) as a potential species to improve the soil and develop ecologically sound saline agriculture. Our nearly 10 years of experimental research, both in a test garden and in the field, indicated that K. virginica adapts excellently to the heavy saline soils of Jiangsu Province, China. The average seed yield of K. virginica in 2001 at Yancheng was 638 kg/ha from 1-year old seedlings. There were significant variations among individuals from the unselected population of K. virginica on growth, quality, and seed yield traits. There is great potential to increase the seed yield if superior clones are selected. The seed yield of 35 selected individuals was six times greater than that of the average. Four growth traits of K. virginica were found to have a significant correlation with seed yield. However, there was no strong positive or negative correlation among seed quality traits. The mean seed weight and the germination ratio of the 35 selected individuals of K. virginica were 16.36±0.32 g and 76.11±1.82%, respectively. The percentage content of oil and crude protein in the seeds was 11.28±0.67 and 8.17±0.19%, respectively. The percentage of seed vigor of the selected individuals was 99%, as determined by soft X-ray radiography.     

滞育和非滞育棉铃虫前胸腺的形态解剖学比较研究

该文用解剖镜和电子显微镜对滞育和非滞育棉铃虫Helicoverpa armigera前胸腺的形态解剖结构进行了比较研究。结果发现滞育棉铃虫的前胸腺细胞及其细胞间隙相对较小,不易着色,细胞核规则,较小,细胞质中几乎见不到光滑内质网和粗面内质网,线粒体极少,这些观察到的现象充分说明滞育棉铃虫的前胸腺活性较低。     

有机酸在植物解铝毒中的作用及生理机制

酸性土壤上铝毒是限制作物产量的一个重要障碍因子,具有螯合能力的有机酸在植物铝的外部排斥机制和内部耐受机制均具有重要作用,在铝的外部排斥解毒过程中,植物通过根系分泌有机酸进入根际,如柠檬酸,草酸,苹果酸等与铝形成稳定的复合体,阻止铝进入共质体,从而达到植物体外解除铝毒害效应的目的,且分泌的有机酸对铝的胁迫诱导表现出高度的专一性,分泌的关键点位于根尖,不同的物种间分泌的有机酸种类,分泌的模式及生理机理存在差异,在铝积累型植物的内部解毒过程中,有机酸与铝形成稳定的化合物,降低植物体内铝离子的生理活性,从而降低细胞内铝离子的毒害效应,如绣球花中铝与柠檬酸形成1：1的复合体,荞麦内铝与草酸形成1：3的复合体,本文就有机酸在植物忍耐和积累铝中的作用及生理机制作一简要综述。     

草鱼呼肠孤病毒在CIK细胞中复制及形态发生的研究

以草鱼呼肠孤病毒（ＧＣＲＶ）感染的草鱼肾细胞系（ＣＩＫ）为模型,进行了草鱼呼肠孤病毒在细胞内的形态发生的研究。当病毒以感染复数为５￣１０ＰＦＵ／ＣＥＬＬ感染ＣＩＫ细胞时,在病毒感染细胞４ｈ以内的切片中,可观察到脱去部分外层衣壳的不完整病毒颗粒。感染细胞８ｈ,可观察到浆胞内病毒发生基质,其内含有大量的直径约５０ｎｍ的亚病毒颗粒,无外层蛋白结构。感染１２￣１６ｈ后,这些亚病毒颗粒装配上外层蛋白结构,形     

新城疫病毒非编码序列的遗传演化趋势

【目的】探讨新城疫病毒全基因序列中非编码序列的分子演化规律。【方法】结合本研究室2012年自产蛋下降鸭群中分离测序的一株鸭源新城疫病毒全序列,从GenBank下载35株不同基因型新城疫病毒全长cDNA序列,获取非编码序列,分别绘制引导序列、尾随序列、F-HN及HN-L基因间隔序列(IGS)的遗传进化树,比较编码基因内5’及3’UTR序列核苷酸序列替代特点。【结果】非编码序列的长度及位置高度保守,而其核苷酸基因序列在不断发生变异,且变异趋势与编码基因序列相一致。【结论】新城疫病毒在整个基因组上编码和非编码序列同步发生变异。     

有机配体对稀土元素在小麦体内积累和分异的影响

采用营养液培养和添加外源混合稀土等方法,研究了有机配体柠檬酸、EDTA和DTPA对稀土元素在小麦的根和叶中积累与分异的影响。结果表明,低浓度有机配体对小麦根和叶中的稀土元素,尤其是轻稀土元素的积累有轻微的促进作用,随浓度的升高则表现出显著的降低作用。有机配体对重稀土的作用比轻稀土强,使根和叶中稀土元素的分布曲线向重稀土相对亏缺的方向发展。3种配体对轻、重稀土分异的作用强度为:EDTA>DTPA>柠檬酸。通过VM INTEQ计算表明,在EDTA和DTPA作用下小麦叶中稀土元素的积累与轻、重稀土的分异主要由溶液中呈自由离子态稀土元素的含量和组成控制;柠檬酸作用下小麦叶中稀土元素的变化与自由离子态稀土的含量和组成关系较弱,推测REE-柠檬酸络合物可被小麦直接吸收并运转到小麦的叶中。     

鲫鱼PKZ Zα结构域与d(GC)、d(TA)重组质粒的结合

Zα是能够特异性识别并结合左旋DNA(Z-DNA)的蛋白结构域,首先在人ADAR1中鉴定,随后又在ZBP-1(DLM-1)和E3L等蛋白质中发现了该结构域．鲫鱼PKZ是首次报道的具有Zα结构域的鱼类eIF2α激酶．为深入了解鲫鱼PKZ Zα的功能,原核表达并亲和层析纯化了3种多肽,即野生型PZα(Zα1Zα2)、替换型P(Zα1)2(Zα1Zα1)和点突变型（PZαK34A、PZαS35A、PZαR39A、PZαP57A）．同时,构建了含有d(GC)6、d(GC)13、d(TA)13特殊插入序列的3种重组质粒,用于体外模拟Z-DNA．凝胶阻滞实验分析了3种多肽分别与重组质粒的亲和性结果表明,PZα和P(Zα1)2能够与d(GC)重组质粒结合,并且随着多肽含量的增加,阻滞效应越明显．与野生型PZα相比,替换型P(Zα1)2结合d(GC)重组质粒的能力更强PZα和P(Zα1)2还能微弱地与d(TA)13重组质粒结合．点突变型多肽都不能与重组质粒结合,暗示鲫鱼PKZ Zα结构域中这4个氨基酸残基在结合核酸分子的过程中非常关键．该文结果有利于进一步揭示鱼类PKZ Zα结构域与Z-DNA结合的分子机理．     

利用土壤宏基因组技术定向筛选抗生素产生菌的方法学建立

为了快速从土壤中定向筛选抗生素产生菌, 本研究利用宏基因组技术进行了土壤中抗生素产生菌快速筛选方法的探索。对6 种不同土质的土壤利用液氮冷冻法提取土壤基因组DNA 并用PVPP柱层析法进行纯化, 每克湿土可得到32.25?61.25 μg DNA, 片段大小为23 kb左右, 说明宏基因组DNA样品完整, 16S rDNA的 PCR结果证明了该基因组DNA纯度可用于后期的分子操作。利用Herbimycin产生菌掺入法进行了抗生素产生菌筛选方法学的验证。结果证明, 每克湿土掺入103个Herbimycin产生菌时, 利用Herbimycin合成基因簇的特定引物即可从所提取的土壤基因组DNA中扩增出目标条带, 并且可以利用传统菌种分离方法从土壤中重新分离出来被掺入到土壤的Herbimycin产生菌。这些结果证明本研究建立的定向抗生素产生菌筛选方法, 具有快捷、灵敏的特点, 大大减少传统筛选方法的工作强度和时间, 为微生物新药的研发建立一种全新的研究方法。