双层量子点阵列浮栅结构纳米存储器

设计了一种新型的存储器结构单元——锗／硅双层量子点阵列浮栅结构纳米存储器．对存储器样品的C—V测量结果显示了这种结构的P沟道器件有着更加优异的存储性能．数值模拟表明了该器件的编程速度在微秒量级，而保留时间长达10年（约10^8S）．这种新型的存储器结构单元有效地解决了目前硅基纳米存储器存在的工作电压和长久存储之间的矛盾，为硅基纳米存储器的实用化拓宽了道路．     

Application of imidacloprid controlled-release granules to enhance the utilization rate and control wheat aphid on winter wheat

During winter wheat production, aphids need to be controlled with pesticides for the entire growth period. Controlled-release technology has been regarded as an alternative method for the improvement of pesticide efficiency. This study investigated two types of imidacloprid controlled-release granule (CR-GR): 2% imidacloprid CR-GR and 0.2% imidacloprid pesticide-fertilizer controlled-release granule (PF-CR-GR) when wheat was sown in winter. The release performance, utilization rate, terminal residues in edible parts, control effect on aphids, and achieved winter wheat yield were evaluated for both laboratory experiments and field application. Imidacloprid PF-CR-GR released more quickly in aqueous medium than CR-GR because of its good water solubility. After CR-GR treatments, the concentrations in wheat roots and soil were similar throughout the entire sampling period, and the concentrations in shoots were about 10–20% of those in roots. Imidacloprid was better absorbed when CR-GR was used as root treatment, compared with foliar treatment. Field application showed that imidacloprid CR-GR and PF-CR-GR controlled aphids throughout the entire growth period of winter wheat and improved the wheat yield. These findings identified application of imidacloprid CR-GR and PF-CR-GR on winter wheat as an effective way to enhance the pesticide utilization rate and ensure adequate yield. This paper provides a theoretical basis for the scientific use of pesticides and guides scientific pesticide application.     

基于转录组测序的半滑舌鳎长链非编码RNA的初步鉴定与分析

以抗病家系与易感家系半滑舌鳎为材料,进行哈维弧菌感染实验,并对易感家系感染前(CsSU)、易感家系感染后(CsSC)、抗病家系感染前(CsRU)、抗病家系感染后(CsRC)4组进行转录组测序,根据RNA-seq数据挖掘半滑舌鳎长链非编码RNA信息;通过生物信息学分析,筛选出与抗哈维弧菌病相关的差异长链非编码RNA(long non-coding RNA, lncRNA)。结果显示,共识别出4 584个lncRNA座位,包含5 714个转录本;其基本特征与编码基因的比较分析,lncRNA的GC含量低于编码基因,单外显子基因数多于编码基因,转录本的平均长度长于编码基因,基因表达量低于编码基因。对4组样品进行两两比较(CsRU vs CsSU、CsRC vs CsSC、CsRC vs CsRU、CsSC vs CsSU)分别筛选出818、813、261、140个差异表达lncRNA,其中CsRU与CsSU之间、CsRC与CsSC之间lncRNA数目差异最多,通过聚类分析确定了各实验组的表达模式之间的联系,CsRU与CsSU之间的表达模式最为相近。通过共表达分析,预测出lncRNA和274个编码基因可能存在14 539种相互关系,并进行了功能注释,进而筛选出7个关键lncRNA。qRT-PCR结果显示,差异表达lncRNAs的表达模式和转录组数据得到的基本一致。研究结果为揭示lncRNA在半滑舌鳎抗哈维弧菌免疫调控反应中的作用提供重要的参考数据。     

俄罗斯城市森林采风

踏着四月的春光,我们走进俄罗斯,来到向往已久的十月革命的故乡。从莫斯科到圣彼得堡,从喧嚣的闹市到寂静的校园,20天紧张而愉快的培训生活,使我们不仅亲身感受到中俄两国人民的深厚友谊,而且领略了俄罗斯城市森林迷人的风采,至今难以忘怀。       

吉林市城市森林建设的主要成就及做法

吉林市地处吉林省中东部,属长白山向松嫩平原的过渡地带,是吉林省的第二大城市,总面积2.7万平方公里,人口450万人。       

根部施药防治青桐木虱

采用根部施药防治青桐木虱,是一种行之有效的施药方法,具有操作简便、防治效果高、对环境污染小的特点。树干直径10 cm左右的青桐树,用10%吡虫啉可湿性粉剂4-8 g.株^-1,根际施药或根冠施药,对青桐木虱的防治效果良好,药后5 d相对防效均达90%以上,且持效期较长。     

Honey Bees (Hymenoptera: Apidae) Decrease Foraging But Not Recruitment After Neonicotinoid Exposure

Honey bees (Linnaeus, Hymenoptera: Apidae) are widely used as commercial pollinators and commonly forage in agricultural and urban landscapes containing neonicotinoid-treated plants. Previous research has demonstrated that honey bees display adverse behavioral and cognitive effects after treatment with sublethal doses of neonicotinoids. In laboratory studies, honey bees simultaneously increase their proportional intake of neonicotinoid-treated solutions and decrease their total solution consumption to some concentrations of certain neonicotinoids. These findings suggest that neonicotinoids might elicit a suboptimal response in honey bees, in which they forage preferentially on foods containing pesticides, effectively increasing their exposure, while also decreasing their total food intake; however, behavioral responses in semifield and field conditions are less understood. Here we conducted a feeder experiment with freely flying bees to determine the effects of a sublethal, field-realistic concentration of imidacloprid (IMD) on the foraging and recruitment behaviors of honey bees visiting either a control feeder containing a sucrose solution or a treatment feeder containing the same sucrose solution with IMD. We report that IMD-treated honey bees foraged less frequently (–28%) and persistently (–66%) than control foragers. Recruitment behaviors (dance frequency and dance propensity) also decreased with IMD, but nonsignificantly. Our results suggest that neonicotinoids inhibit honey bee foraging, which could potentially decrease food intake and adversely affect colony health.     

植物体内磷转运子的研究进展

近年来，人们对植物营养的遗传背景有了不断深入的了解，特别是磷营养。这一领域的研究工作开展得较早，而且随着分子生物学的快速发展已深入到分子水平，其中关于植物磷转运子的报道特别多。笔者对其结构、功能及表达调控方面的研究进展作一综述。     

氮、磷、钾对油研10号油菜产量和品质的影响

采用三元二次通用正交旋转组合设计,研究了直播栽培方式下氮、磷、钾与油研10号油菜品种产量、产油量、含油率、芥酸、硫甙、饼粕蛋白质含量之间的关系.结果表明,在试验设计水平范围内,随着施氮量的增加,产量、产油量、芥酸呈逐渐降低趋势,含油率和饼粕蛋白质含量呈逐渐增加趋势.芥酸、含油率、饼粕蛋白质含量与施磷量间呈开口向上的抛物线关系,呈现出高-低-高的变化趋势.同时获得产量200kg·667m-2和产油量85kg·667m-2的优化农艺措施方案分别为纯氮6.46～7.59kg·667m-2、P2O5(磷肥)6.58～8.42kg·667m-2、K2O(钾肥)10.37～13.63kg·667m-2和纯氮9.06kg·667m-2、P2O5(磷肥)6.20～8.80kg·667m-2、K2O(钾肥)9.69～14.31kg·667m-2.     

美国城市生态廊道建设及其对我国的启示—以丹佛为例

美国等西方国家比较重视城市生态廊道建设,作者根据实地观察和体验,介绍了美国西部科罗拉多州丹佛市的城市生态廊道建设,文中提出我国在城市森林系统建设中存在过分人工化倾向,建议借鉴国外经验,结合国内实际改进一些作法,还对北京市绿化提出若干建议。