Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 24 )

2018 ( 182 )

2017 ( 173 )

2016 ( 185 )

Custom range...

Search Results: 1 - 10 of 14246 matches for " Zuorui Shen "
All listed articles are free for downloading (OA Articles)
Page 1 /14246
Display every page Item
用Peason Ⅲ型曲线拟合菜蚜种群空间分布型的初步研究

Shen Zuorui,

生态学报 , 1985,
Abstract: 为寻求某些研究r-对策昆虫种群在其生境空间的概率分布的方法,我们用Pesson Ⅲ型曲线(简称P-Ⅲ分布)拟合了菜蚜种群的9批抽样数据,它们是1981年在菜蚜种群发生期的不同日期抽取于北京郊区的秋白菜田间。 我们可以通过MTLK方案将P-Ⅲ分布用于拟含9批样本中经过初步判断具有可拟性的3批数据: M——初值估计采用矩法,即以矩法估计P-Ⅲ分布的三个基本参数:平均数Ex,离势系数Cv和偏差系数Cs,做为下面将要进行的适线法之初始值。 T——P-Ⅲ分布的累积概率值p是由数表给出,具体做法是由给定的Cs值和抽样数据x的标准化变量φ值在数表中查得p值。 L——以适线法实现良好的拟合,该法是在计算机上通过一项最优化技术,即在Cv-Cs直角坐标系中产生一组正三角形(简称GRT法),以自动得到拟合的良好结果。 K——对拟合优度采用柯尔莫哥洛夫检验。 拟合结果,3批样本中有两批可理论地拟合。该P-Ⅲ分布的概率密度函数为f(x)=βα/г(α)(x-b)~(α-1)*exp(-β*(x-b)),(b≤x<∞)其中b=Ex*(1-2*Cv/Cs),α=4/Cs~2,β=2/(Ex*Cv*Cs),经过拟合后,b、α和β的取值便更加适合了。 本文得出的结论是: 1.连续型概率分布可以被用来拟合某些r-对策昆虫种群的田间抽样数据,这是与传统的方法不同的。这里所谓传统的方法是指用于拟合k-对策昆
Identification and expression profiling of putative odorant-binding proteins in the malaria mosquitoes, Anopheles gambiae and A. arabiensis
Zhengxi Li,Jing-Jiang Zhou,Zuorui Shen,Field Lin
Science China Life Sciences , 2004, DOI: 10.1360/03yc0232
Abstract: Olfaction plays a major role in host-seeking behaviour of mosquitoes. An informatics-based genome-wide analysis of odorant-binding protein (OBP) homologues is undertaken, and 32 putative OBP genes in total in the whole genome sequences of Anopheles gambiae are identified. Tissue-specific expression patterns of all A. gambiae OBP candidates are determined by semi-quantitative Reverse Transcription (RT)-PCR using mosquito actin gene as internal expression control standard. The results showed that 20 OBP candidates had strong expression in mosquito olfactory tissues (female antennae), which indicate that OBPs may play an important role in regulating mosquito olfactory behaviours. Species-specific expression patterns of all putative anopheline OBPs are also studied in two of the most important malaria vectors in A. gambiae complex, i.e. A. gambiae and A. arabiensis, which found 12 of the putative OBP genes examined displayed species-differential expression patterns. The cumulative relative expression intensity of the OBPs in A. arabiensis antennae was higher than that in A. gambiae (the ratio is 1441.45:1314.12), which might be due to their different host preference behaviour. While A. gambiae is a highly anthropophilic mosquito, A. arabiensis is more opportunistic (varying from anthropophilic to zoophilic). So the latter should need more OBPs to support its host selection preference. Identification of mosquito OBPs and verification of their tissue- and species-specific expression patterns represent the first step towards further molecular analysis of mosquito olfactory mechanism, such as recombinant expression and ligand identification.
Effect of elevated CO_2 concentration and imidacloprid on culturable bacteria and microbial biomass carbon in cabbage(Brassica oleracea L. var. capitata)soil

YAO Yanhong,GE Feng,SHEN Zuorui,

生态学报 , 2010,
Abstract: Responses of bacteria in the presence rhizosphere soil and soil microbial biomass carbon in non-rhizosphere cabbage to elevated CO2 and three concentrations of imidacloprid were examined in the open-top chambers(OTC).Numbers of bacteria in rhizosphere soil increased significantly(P<0.01) with elevated CO2 but imidacloprid had no effect on bacteria.Microbial biomass carbon was lower in non-rhizosphere of cabbage under elevated CO2 than ambient CO2 concentrations when imidacloprid was not applied.Regardless o...
Influence of host plant species on the development and reproduction of hawthorn spider mite Tetranychus viennensis Zacher

LI Dingxu,HOU Yueli,SHEN Zuorui,

生态学报 , 2005,
Abstract: Hawthorn spider mite (HSM), Tetranychus viennensis Zacher, is an important and damaging pest in apple orchards worldwide and has become the most serious pest on apple in north China. The hosts of this pest are mainly fruit trees of the family Rosaceae. To assess host suitability of deciduous fruit trees in family Rosaceae, a leaf disc bioassay was employed to investigate the influence of five species of deciduous fruit trees, which included apple, peach, plum, cherry, and apricot, on the development and rep...
Effects of Sublethal Doses of Insecticides on Predation of Multicolored Asian Ladybird Harmonia axyridis (Pallas) (Cole- optera: Coccinelliodae)

WANG Xiaoyi,SHEN Zuorui,

生态学报 , 2002,
Abstract: Insecticides and natural enemies are the two main means to control insect pests at present. A problem is coming that after spraying of insecticides in the field, some natural enemies were inevitably influenced at lethal or sublethal degree. In order to seek better techniques for coordinating the chemical and biological control measures, and improve the level of integrated pest management, effects of sublethal doses of four insecticides, i.e., imidacloprid, rotenone, fenvalerate and abamectin, on the functio...

Wan YongJi,Shen ZuoRui,

菌物学报 , 2005,
Abstract: 微孢子虫是一类专营寄生生活、无线粒体的单细胞真核生物,在分类学上一直归类于原生生物界,原生动物亚界。但最近对微孢子虫分子进化和系统发育的研究认为微孢子虫与真菌具有很近的亲缘关系,美国生物技术信息中心(NCBI)2002年将微孢子虫归类于真菌。本文予以综述和评论。
Effect of pollen of conventional cotton and transgenic Cry1Ac+CpTI cotton on reproduction and survival of the parasitoid wasp Trichogramma confusum Viggiani(Hymenoptera: Trichogrammatidae)

GENG Jinhu,SHEN Zuorui,LI Zhengxi,ZHENG Li,

生态学报 , 2005,
Abstract: The cotton bollworm, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), is the most important pest of cotton in China, causing both quantitative and qualitative losses. Trichogramma confusum Viggiani (Hymenoptera: Trichogrammatidae) is an endemic egg parasitoid of cotton bollworm H. armigera in China and is a potential biological control agent. The availability and quality of food played an important role in determing the effectiveness of parasitoids as control agents. Adult Trichogramma spp. are known...
Sublethal effects of insecticides on fecundity of multicolored Asian ladybird Harmonia axyridis

WANG Xiaoyi,SHEN Zuorui,XU Wenbing,LU Jian,

应用生态学报 , 2003,
Abstract: The effects of sublethal doses of 6 insecticides (imidacloprid, rotenone, fenvalerate, abamectin, pirimicarb and azadirachtin) on the fecundity of multicolored Asian ladybird Harmonia axyridis were determined respectively. The results showed that in all treatments, the daily average number of eggs per female ladybird was about 40-55. Ladybirds pretreated with imidacloprid by contact and feeding methods, and with rotenone by feeding method produced significantly fewer eggs, compared with control. But the accumulative oviposition of ladybirds pretreated with 6 insecticides at sublethal level was no significant differences, compared with untreated ladybirds. The hatching rates of the eggs laid by ladybirds pretreated with 6 insecticides by two methods were all lower than that of control. The accumulative survivals from egg to pupal stage of all treatments decreased significantly. The developmental duration from egg to pupa of those treated with imidacloprid by two methods and with fenvalerate by contact method prolonged significantly, while that of those treated with rotenone by two methods and with fenvalerate, abamectin, pirimicarb, and azadirachtin by feeding method shortened obviously, but that of those treated with rotenone and abamectin by contact method had no differences with control. After the eggs were immersed with sublethal concentrations of imidacloprid, rotenone, fenvalerate and abamectin, the successful hatching rates were all lower than that of control, and the development periods prolonged clearly. The 1st instar larval survival rates of those treated with fenvalerate decreased significantly, and the survivals from 2nd instar larval to pupal stage also reduced to some extent. The total developmental duration of those treated with rotenone and fenvalerate prolonged significantly. These findings suggested that the effects of insecticides at low doses on the fecundity of ladybird were very complicated. The class, action mode, toxicity and exposure route of insecticides could affect the results of experiments.
ARIMA Model in the Application of Shanghai and Shenzhen Stock Index  [PDF]
Shichang Shen, Yue Shen
Applied Mathematics (AM) , 2016, DOI: 10.4236/am.2016.73016
Abstract: In the paper, based on the data of Shanghai and Shenzhen 300 stock index in 2011, the ARIMA model was established by using Eviews 6, and the historical trend of stock price was found out. The model was used to provide a reference for the investors.
Understanding the Determinants of Consumers’ Willingness to Pay for Eco-Labeled Products: An Empirical Analysis of the China Environmental Label  [PDF]
Junyi Shen
Journal of Service Science and Management (JSSM) , 2012, DOI: 10.4236/jssm.2012.51011
Abstract: This study applies data from a web-based survey conducted in mainland China to examine the determinants of consumers’ willingness to pay (WTP) for seven different product categories awarded with China Environmental Label and com- pare the mean WTP estimates among these categories. The Interval Regression method is used for estimation. The results indicate that Chinese consumers who regard environmental conservation as being more important than life convenience, who believe purchasing the eco-labeled products is good for the environment, and who have the experience in purchasing eco-labeled products are willing to pay more for those products with environmental label or eco-label. In addition, socio-demographic characteristics such as gender, age, education and household income are found to be important factors to affect Chinese consumers’ WTP amounts. Finally, the results of pair-wise comparison among the mean WTP estimates of various eco-labeled products indicate that most of them are different, which implies that the degrees of Chinese consumers’ willingness to pay extra money for China Environmental Label are different based on the types of products.
Page 1 /14246
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.