重庆地区柑桔大实蝇系统监测研究

柑桔大实蝇Bactrocera minax是柑桔类植物果实的重要害虫,以往对该虫的发生监测仅局限于通过果园诱集和室内外养蛹监测成虫的发生期。本研究综合应用室外养蛹、桔园系统调查、成虫诱集和蛆果解剖等技术手段,以期了解柑桔大实蝇的产卵进度、幼虫发育进度、蛆果落地进度、幼虫化蛹进度以及蛹的羽化进度。研究结果表明,重庆地区柑桔大实蝇产卵盛期为6月下旬-7月上旬,高峰期为6月下旬末-7月初;一龄、二龄和三龄幼虫的发生盛期分别为9月中旬-10月初、10月上旬-下旬和10月中旬-11月初;受害蛆果落地盛期为10月上旬-下旬,与二龄和三龄幼虫的发生盛期吻合;室外养蛹的成虫羽化盛期为5月上旬-中旬末,但果园成虫诱集的盛期为6月中旬-下旬,较室外养蛹的成虫发生盛期推迟30 d左右,对出现此种情况的原因作者做了初步分析。研究结果还表明,各虫态的累计发生进度均可用逻辑斯缔方程拟合,从而可计算出各虫态发生进度为16%、50%和84%的始盛期、高峰期和盛末期。研究结果对于柑桔大实蝇的发生期预测和防治具有重要指导意义。     

硒-铁蛋白电化学反应器储存含磷化合物的研究

由透析袋、硒－铁蛋白、恒流泵、电导仪、磁力搅拌器及电化学系统等构成成硒－铁蛋白电化学反应器。该反应器可储存流动水体中微量含磷化合物于铁蛋白的蛋白壳内,其储存量高低与流动水体中的含磷化合物含量成正比关系。经硒改造后的硒－铁蛋白能提高有机磷农药的储存量,其储存能力与铁蛋白种类无关,可能与铁蛋白自身构象有关。     

双侧颈总动脉结扎对大鼠学习记忆相关脑区血流量的影响

目的为建立双侧颈总动脉结扎致大鼠血管性痴呆模型,观察了大鼠双侧颈总动脉结扎后不同脑区脑血流量的影响。方法采用激光多普勒血流仪,测定麻醉大鼠双侧颈总动脉结扎后１０ｍｉｎ内不同脑区脑血流量变化。结果大鼠双侧颈总动脉结扎后,平均脑血流量减少额区６７８３％、顶区５６８２％、枕区１６１６％、Ｍｙｎｅｒｔ基底核５１２１％、尾壳核４１１８％,海马ＣＡ１５１８３和海马ＣＡ２４１２１。结论大鼠双侧颈总动脉结扎后与学习记忆有关的脑区脑血流量均显著下降     

Behaviour of late-instar gypsy moth larvae in high and low density populations

ABSTRACT. 1. Using scaffolding and night-vision equipment, we observed fifth and sixth instars of the gypsy moth, Lymantria dispar (L.), on Quercus velutina Lam. in the field.
2. In low-density populations, larvae fed at night and spent the day resting in sheltered sites away from the canopy. In high-density populations, larvae remained in the canopy throughout the day and night, and the amount of feeding during daylight hours increased with population density.
3. Larvae at all population densities used a similar sequence of behaviours and sampled a number of leaves when selecting feeding sites, but larvae in high-density populations switched feeding sites more frequently and fed continuously for shorter periods.
4. Larvae seldom interfered with each other's feeding in any of the populations.
5. When fifth instars were collected from the field and held for 24 h in an electronic feeding monitor, they maintained feeding rhythms that were characteristic of their source populations. Larvae spent more time crawling and less time feeding when offered foliage from high-density rather than low-density populations.     

实时定量PCR技术及应用

实时定量PCR(Real-tim e Quantitative Polym erase Chain Reaction,RQ-PCR),是20世纪90年代中期发展起来的基于PCR技术的利用不同的荧光检测来给核酸定量的技术。克服了传统PCR的许多不足,能准确敏感地检测模板浓度,DNA拷贝数和检测基因变异。综述了RQ-PCR技术的原理,RQ-PCR实时定量检测系统及应用。     

Monitor lizards: a pan-African check-list of their zoogeography (Sauria: Varanidae: Polydaedalus)

Aim This goal of this paper is to present an up‐to‐date, accurate check‐list and distribution of the monitor lizards on the African continent. No such list of their distribution has been attempted since Robert F. Mertens' (1942) treatise (Abhandlungen Senckenbergischen Naturforschenden Gesellschaft, 462 , 465 , 466 ). Location The localities included herein are all countries on the African continent, and adjacent islands, with a list of Varanus known to Yemen and Saudi Arabian Republics included for clarity. One fossil Varanus rusingensis is included, as it is the first, and only described, fossil African Varanus known. Methods Locality records were reviewed from literature sources, museum voucher specimens, personal comments, field observations and photographic records. Results A summation of 3,268 locality records are included herein from the methods listed, with maps depicting these records. Main conclusions From the locality records listed herein, it is evident that the Nile monitor (V. niloticus) has the widest distribution, and that the Yemen monitor (V. yemenensis) has the most restricted distribution; paradoxically, both features may be indicative of their relic habitation on the African continent.     

一种利用分泌型荧光素酶基因表达变化监测活细胞中miRNA活性的新方法

建立了一种以分泌型的荧光素酶Gluc为报告基因的miRNA传感器质粒(命名为Gsensor)监测活细胞中miRNA(microRNA)活性的方法。首先构建了pAAV2neo-Gluc-MCS-polyA质粒作为Gsensor的空载体,同时其中的MCS位点可供插入miRNA的靶序列。以miR142-3p为检测对象,将1个和3个拷贝的与miR142-3p完全互补靶序列分别插入pAAV2neo-Gluc-MCS-polyA中,构建成miR142-3p Gsensor和miR142-3p Gsensor-3。将它们分别转染至U937细胞中,检测培养上清中Gluc的表达水平。结果显示二者均可有效反映U937细胞中miR142-3p的抑制活性(分别与Gsensor空载体相比),提示Gsensor中采用一个拷贝的miRNA靶序列即可满足检测要求。并且miR142-3p Gsensor也能有效地反映出Anti-miR142对miR142-3p活性的抑制作用。随后,分析了时间、转染剂量对Gsensor检测结果的影响。结果表明,在U937细胞中miR142-3p Gsensor表现的miR142-3p活性在48h后趋于稳定;Gsensor转染剂量在0.001~0.05pg/cell范围内不影响其功能。最后,利用miR142-3p Gsensor检测了HEK293、U937、K562、SP2/0和P815细胞内miR142-3p活性,结果发现miR142-3p活性在U937、K562、SP2/0和P815细胞中均较高,而在HEK293中几乎没有活性。用QRT-PCR方法检测miR142-3p的相对拷贝数。结果表明,在HEK293、U937和K562细胞中,miR142-3p活性与其相对拷贝数呈正相关。本研究表明Gsensor可作为一种有效的miRNA活性检测工具,为体外实时动态监测miRNA活性提供了一种新方法。     

氟磺酰胺复配毒饵对红火蚁的田间防治效果

在深圳市龙岗区和宝安区对氟磺酰胺复配毒饵进行药效评价,试验结果表明,施药后3～15d,龙岗实验区蚁巢周围均有死亡工蚁陆续出现。第7d时,0.75%氟磺酰胺复配毒饵防治效果为16.99%,第28d时防治效果达47.43%,在试验结束的第140d时防治效果达97.93%;对照药剂0.5%氟磺酰胺毒饵对红火蚁Solenopsis invicta Buren的防除效果迅速,在第7d防治效果达50%以上。在宝安实验区,蚁巢的防治效果也随施药后时间的延长而增加,第28d的防治效果为51.65%,试验结束时防治效果达到94.72%;对照药剂0.5%氟磺酰胺毒饵42d防治效果达最大值为92.88%。上述结果显示,0.75%氟磺酰胺复配毒饵具有较快压低红火蚁种群密度,持效控制实验区红火蚁种群的特点。     

用显示器测量办公亮度环境下的人眼对比度敏感视觉特性

对比度敏感是描述人眼视觉系统空间特性的主要指标之一,对比度敏感函数是反映不同条件下的对比度敏感与空间频率之间的关系。人眼对比度敏感数据的测量受到环境亮度较大的影响,为了研究常用办公环境条件下的人眼对比度敏感情况,对6位青年在环境亮度分别为153,312,470 cd/m2和暗室条件下,在距离为2米处观测11种空间频率的矩形光栅进行测量,光栅用显示器进行显示,其平均亮度分别为60和90 cd/m2。实验结果表明,对于相同频率的光栅,人眼对比度敏感程度随着环境亮度的增加而减小,而且人眼在暗室环境下比在办公环境条件下对亮度光栅更敏感;但是在观测平均亮度为60cd/m2的光栅时,人眼特殊地对在环境亮度为312 cd/m2的条件下更敏感。     

Learning-aided predictor integration for system performance prediction

The integration of multiple predictors promises higher prediction accuracy than the accuracy that can be obtained with a single predictor. The challenge is how to select the best predictor at any given moment. Traditionally, multiple predictors are run in parallel and the one that generates the best result is selected for prediction. In this paper, we propose a novel approach for predictor integration based on the learning of historical predictions. Compared with the traditional approach, it does not require running all the predictors simultaneously. Instead, it uses classification algorithms such as k-Nearest Neighbor (k-NN) and Bayesian classification and dimension reduction technique such as Principal Component Analysis (PCA) to forecast the best predictor for the workload under study based on the learning of historical predictions. Then only the forecasted best predictor is run for prediction. Our experimental results show that it achieved 20.18% higher best predictor forecasting accuracy than the cumulative MSE based predictor selection approach used in the popular Network Weather Service system. In addition, it outperformed the observed most accurate single predictor in the pool for 44.23% of the performance traces.