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Research Advances in the Control of Spider Mites Using Bioactive Substances of Biological Origin
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作者 Tongshu DAI Kaicheng LIU Yanjie LUO 《Asian Agricultural Research》 2025年第11期51-53,共3页
Spider mites are significant pests in agricultural production.The increasing resistance of spider mites,along with environmental pollution and ecological imbalance caused by their control,is primarily attributed to th... Spider mites are significant pests in agricultural production.The increasing resistance of spider mites,along with environmental pollution and ecological imbalance caused by their control,is primarily attributed to the long-term use of chemical acaricides in agriculture.In contrast,bioactive substances of biological origin offer advantages such as wide availability,environmental friendliness,and low tendency to induce resistance,making them a research hotspot for spider mite control.This review summarizes recent advances in the use of plant-derived active compounds(exemplified by extracts from Veratrum rhizomes),RNA interference(RNAi)technology,and microorganism-derived active substances for controlling spider mites.These bioactive agents exert acaricidal effects by disrupting the nervous system,interfering with metabolic processes,or silencing key genes in mites,demonstrating favorable efficacy and considerable potential for development.However,challenges remain,including poor environmental stability,slow action,high production costs,and insufficient understanding of their effects on non-target organisms.Therefore,future research should focus on the screening and development of novel bioactive substances of biological origin,elucidation of their mechanisms of action,optimization of formulation technologies,and assessment of their ecological safety.These efforts will provide valuable insights for promoting the advancement of bioactive substances and supporting sustainable agricultural development. 展开更多
关键词 Bioactive substances of BIOLOGICAL ORIGIN spider MITE CONTROL RNA interference Plant-derived ACTIVE substances Microorganism-derived ACTIVE substances
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Characterization of Spider Plant (Cleome gynandra L.) under Samanko Conditions
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作者 John R. Nzungize Ouindyam C. Ouedraogo +4 位作者 Keriba Kante Fatogoma Tanou Boubaca Goro Mariam Sogoba Roland Schafleitner 《Agricultural Sciences》 2024年第12期1429-1445,共17页
This study aimed to evaluate spider plant (Cleome gynandra L.) accessions for agronomic and morphological characteristics. Sixty-four accessions, characterized under Samanko conditions, were assessed using a phenotypi... This study aimed to evaluate spider plant (Cleome gynandra L.) accessions for agronomic and morphological characteristics. Sixty-four accessions, characterized under Samanko conditions, were assessed using a phenotypic evaluation system. Observations and biometric measurements covered 34 variables, revealing considerable agro-morphological variability among the accessions, particularly in qualitative traits. Significant differences were observed at the 5% threshold between accessions for variables such as plant height, plant diameter, pod width, and 50% flowering date. Several positive correlations were also noted between the traits. The study identified three distinct groups of accessions based on diversity structuring. The first group mainly comprised accessions with a short growth cycle and average yield. The second group was characterized by accessions with superior agronomic performance, featuring a long cycle and high yields. In contrast, class III exhibited lower agronomic performance compared to the other two classes. The variability identified in this study offers potential for use in Cleome gynandra L. improvement programs in Mali, with class II accessions distinguished by their dark green, hairy stems and superior agronomic performance being the most promising candidates for improvement. 展开更多
关键词 MALI spider Plant Cleome gynandra (L.) DIVERSITY Agromorphological
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完美音浪——法拉利12CILINDRI SPIDER
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作者 王迪 《世界汽车》 2024年第7期16-23,共8页
近日,法拉利12Cilindri Spider在迈阿密海滩上的一场独家活动上亮相。作为一款设计理念承袭自20世纪50与60年代法拉利Gran Turismo敞篷车的新款车型,该车将公路赛车无与伦比的性能、12缸发动机声浪以及长途驾驶舒适性结合在一起,并在设... 近日,法拉利12Cilindri Spider在迈阿密海滩上的一场独家活动上亮相。作为一款设计理念承袭自20世纪50与60年代法拉利Gran Turismo敞篷车的新款车型,该车将公路赛车无与伦比的性能、12缸发动机声浪以及长途驾驶舒适性结合在一起,并在设计上打破了法拉利双座berlinetta Spider跑车一贯的肌肉感,采用了一种更加未来主义、建立在纯粹形式基础上的设计语言。 展开更多
关键词 法拉利 驾驶舒适性 公路赛车 新款车型 纯粹形式 spider 敞篷车 未来主义
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Spider系统中LRU算法的使用和实现 被引量:1
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作者 洪伟铭 《程序员》 2007年第1期116-117,共2页
Spider系统中URL排重操作决定了抓取互联网上内容的速度,用传统的LRU算法来实现Spider系统的URL排重问题过于浪费资源,本文给出了用面向对象的方法设计和实现对象缓存算法,用于处理Spider系统中大量的URL排重操作。
关键词 spider系统 LRU算法 spider系统 URL 面向对象 互联网 操作 抓取
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抢先式多线程Spider在智能搜索引擎中的实现 被引量:3
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作者 董瑞洪 张秋余 +1 位作者 唐静兵 张涛 《计算机工程》 EI CAS CSCD 北大核心 2005年第18期90-92,共3页
互联网的迅速发展,导致了网上信息的爆炸性增长。智能搜索引擎技术已经成为计算机工业界和学术界争相研究、开发的对象。文章在分析网络蜘蛛的工作原理的基础上,结合多线程、类的设计等技术,设计了一种抢先式多线程的Spider程序,并给出... 互联网的迅速发展,导致了网上信息的爆炸性增长。智能搜索引擎技术已经成为计算机工业界和学术界争相研究、开发的对象。文章在分析网络蜘蛛的工作原理的基础上,结合多线程、类的设计等技术,设计了一种抢先式多线程的Spider程序,并给出了该系统运行的结果。 展开更多
关键词 搜索引擎 抢先式 spider 多线程 类的设计
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Composition and Distribution of Soil Spider Assemblages in Three Natural Secondary Forests in Ziwuling, Gansu 被引量:5
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作者 姜双林 李博萍 《Zoological Research》 CAS CSCD 北大核心 2006年第6期569-574,共6页
Soil spiders were pitfall-trapped once every month in three forest vegetation types of Ziwuling natural secondary forest region, Gansu Province from April to October, 2004. A total of 2 164 spiders were collected, bel... Soil spiders were pitfall-trapped once every month in three forest vegetation types of Ziwuling natural secondary forest region, Gansu Province from April to October, 2004. A total of 2 164 spiders were collected, belonging to 43 species in 19 families, captured in 630 pitfall trap collections. Linyphiidae, Gnaphosidae and Lycosodae were found to be the dominant families in all habitat types, and the composition of soil spider assemblages was different between the three habitats. Ecological indices of diversity, richness and evenness were significantly different between the three habitats ( P 〈 0.05). The relative abundance of guilds (based on numbers of individuals) varied greatly (P 〈 0.01), which may releet resource availability within habitat types. The existence of different patterns within the assemblages reflects the importance of maintaining habitat heterogeneity and vegetation types in order to preserve soil spider biodiversity. 展开更多
关键词 Soil spider Pitfall trap Community structure Secondary forest
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Isolation and characterization of Hainantoxin-II, a new neurotoxic peptide from the Chinese bird spider (Haplopelma hainanum) 被引量:4
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作者 潘建义 喻志强 《Zoological Research》 CAS CSCD 北大核心 2010年第6期570-574,共5页
Hainantoxin-II (HnTx-II), a novel neurotoxin, was isolated from the venom of the Chinese bird spider (Haplopelma hainanum) by cation exchange chromatography and reverse-phase HPLC. The toxin was a single chain pol... Hainantoxin-II (HnTx-II), a novel neurotoxin, was isolated from the venom of the Chinese bird spider (Haplopelma hainanum) by cation exchange chromatography and reverse-phase HPLC. The toxin was a single chain polypeptide with calculated molecular weight of 4 253.135 obtained by mass spectrometry. The complete amino acid sequence of HnTx-II was determined by Edman degradation and found to contain 37 residues with three disulfide bonds. Results showed HnTx-II can reversibly paralyze cockroaches for several hours after intra-abdominal injection with ED50 of 16 μg/g and kill the insects immediately at a dose of 60 μg/g. It was also shown to kill mice at a LD50 value of 1.41μg/g after intracerebroventricular injection. Hainantoxin-II shares 91% sequence homology with Huwentoxin-II (HwTx-II), an insecticidal peptide from another bird spider (Haplopelma schmidti) with a unique scaffold. While HnTx-II and HwTx-II both exhibit toxic activities in insects and mammals, HnTx-II shows higher insecticidal activity and lower lethiferous activity of mammals than HwTx-II. These results help clarify structural-functional relationships of the polypeptide toxin. 展开更多
关键词 HnTx-II NEUROTOXIN Insecticidal peptide spider venom Haplopelma hainanum
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Study on Bio-Ecology of the Spider Clubiona corrugate
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作者 李秦晋 王娟 +2 位作者 严真真 赵丽 王智 《Agricultural Science & Technology》 CAS 2015年第6期1243-1246,共4页
Objective] Field and laboratory observation was conducted to investigate Clubiona corrugate. [Method] The trials investigated the bio-ecology and behavior of the spider C. corrugate. [Result] The spider overwintered w... Objective] Field and laboratory observation was conducted to investigate Clubiona corrugate. [Method] The trials investigated the bio-ecology and behavior of the spider C. corrugate. [Result] The spider overwintered with spiderlings, adults and instars turn into adults after 6-8 molts. It had 2-3 generations each year in Hunan, and it owned the character of overlapping of generation in paddies. The average duration of generations of C. corrugate was 158.2 days, and the survival days av-eraged 223.2 days. The female and male mated several times without cannibalistic behavior, average number of eggs female laid throughout its adult life was 371.5, and hatchability can get 85.4%. The sex ratio was 1∶1. Its capability of resistance to starvation and drought was strong. Through indoor observation, the spider can sur-vive 25-61 days under the condition of no water and food. [Conclusion] The behav-ior of C. corrugate was also recorded in detail, and female usual y has a strong a-bility to protect their egg-sacs and spiderlings. At present, the bio-ecology and be-havior of the spider C. corrugate had not been reported. 展开更多
关键词 Clubiona corrugate BIOLOGY ECOLOGY spider
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基于ProActive的分布式并行WebSpider设计
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作者 张林才 梁正友 《计算机工程》 CAS CSCD 北大核心 2008年第19期47-48,52,共3页
单机Web Spider的数据采集速度较慢,采用MPI技术或直接用Java开发分布式Web Spider代价较高。该文利用ProActive中间件提供的主动对象技术、网络并行计算技术、自动部署机制设计实现了P-Spider分布式并行Web Spider。实验结果表明,该P-S... 单机Web Spider的数据采集速度较慢,采用MPI技术或直接用Java开发分布式Web Spider代价较高。该文利用ProActive中间件提供的主动对象技术、网络并行计算技术、自动部署机制设计实现了P-Spider分布式并行Web Spider。实验结果表明,该P-Spider采集速率是单机多线程Web Spider的2.2倍。 展开更多
关键词 WEB spider程序 ProActive中间件 并行 分布式
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可扩展负载均衡Spider的设计
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作者 黎才茂 陈少凡 《微计算机信息》 北大核心 2008年第30期116-118,共3页
随着Web信息的快速增长,如何对Web信息进行检索,获取有价值的信息,已经成为Web信息检索的重点研究内容。本文设计一种可扩展的蜘蛛程序Spider,运用负载均衡策略调度分布Spider的协同工作,实现Web站点页面的分布式下载,在获取页面信息的... 随着Web信息的快速增长,如何对Web信息进行检索,获取有价值的信息,已经成为Web信息检索的重点研究内容。本文设计一种可扩展的蜘蛛程序Spider,运用负载均衡策略调度分布Spider的协同工作,实现Web站点页面的分布式下载,在获取页面信息的同时,获取站点的拓扑结构。 展开更多
关键词 spider 蜘蛛程序 负载均衡 分布式
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可扩展Spider负载均衡策略的研究与实现
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作者 黎才茂 陈少凡 梁保恩 《计算机与数字工程》 2009年第2期38-41,75,共5页
可扩展Spider采用分布式处理技术,是搜索引擎实现信息搜索的不可缺少的代理。在传统负载均衡策略基础上,对Spider的研究提出可扩展Spider的负载均衡策略,该策略能够有效的对Spider的资源进行均衡调度处理,使得Spider具有良好的可扩展性... 可扩展Spider采用分布式处理技术,是搜索引擎实现信息搜索的不可缺少的代理。在传统负载均衡策略基础上,对Spider的研究提出可扩展Spider的负载均衡策略,该策略能够有效的对Spider的资源进行均衡调度处理,使得Spider具有良好的可扩展性和高效性。 展开更多
关键词 负载均衡 spider 网络蜘蛛 分布式
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基于JAVA的多线程SPIDER的设计与实现 被引量:1
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作者 吴小竹 《福建电脑》 2004年第6期62-63,共2页
本文介绍如何利用JAVA语言实现一个多线程的SPIDER程序,该程序作为搜索引擎的数据采集器,能够高效地在网络上搜索并下载网页,以供搜索引擎使用。
关键词 JAVA 多线程 spider程序 搜索引擎 数据采集器
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基于Spider卷积的三维点云分类与分割网络 被引量:11
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作者 王本杰 农丽萍 +2 位作者 张文辉 林基明 王俊义 《计算机应用》 CSCD 北大核心 2020年第6期1607-1612,共6页
针对传统的卷积神经网络(CNN)不能直接处理点云数据,需先将点云数据转换为多视图或者体素化网格,导致过程复杂且点云识别精度低的问题,提出一种新型的点云分类与分割网络Linked-Spider CNN。首先,在Spider CNN基础上通过增加Spider卷积... 针对传统的卷积神经网络(CNN)不能直接处理点云数据,需先将点云数据转换为多视图或者体素化网格,导致过程复杂且点云识别精度低的问题,提出一种新型的点云分类与分割网络Linked-Spider CNN。首先,在Spider CNN基础上通过增加Spider卷积层数以获取点云深层次特征;其次,引入残差网络的思想在每层Spider卷积增加短连接构成残差块;然后,将每层残差块的输出特征进行拼接融合形成点云特征;最后,使用三层全连接层对点云特征进行分类或者利用多层卷积层对点云特征进行分割。在ModelNet40和ShapeNet Parts数据集上将所提网络与PointNet、PointNet++和Spider CNN等网络进行对比实验,实验结果表明,所提网络可以提高点云的分类精度和分割效果,说明该网络具有更快的收敛速度和更强的鲁棒性。 展开更多
关键词 卷积神经网络 spider卷积 点云分类与分割 残差块 鲁棒性
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Economic analysis of spider web airline networks
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作者 Wen-dong Yang, Jin-fu Zhu, Qiang Gao,Wen-fang Wang College of Civil Aviation, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China. 《Journal of Pharmaceutical Analysis》 SCIE CAS 2009年第1期49-53,共5页
The distinct network organization, management, service and operating characteristics of US Southwest Airlines are key elements of its success compared with other airlines. As a network organization type, the spider we... The distinct network organization, management, service and operating characteristics of US Southwest Airlines are key elements of its success compared with other airlines. As a network organization type, the spider web airline network has received more attention. In this paper, we analyzed the relation between the spider web airline network and spider web, and the structure of spider web airline network, built the assignment model of the spider web airline network,and investigated the economics concerned. 展开更多
关键词 spider web spider web airline network economic analysis
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A new species of the trapdoor spider genus Conothele Thorell,1878(Araneae:Halonoproctidae)from Western Ghats,Kerala,India
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作者 Sunil Jose K 《Zoological Systematics》 CSCD 2021年第3期258-263,共6页
A new species of Halonoproctid spider Conothele chinnarensis sp.nov.is described from Chinnar Wildlife Sanctuary in Western Ghats of Kerala,India based on morphological characters.The new species C.chinnarensis sp.nov... A new species of Halonoproctid spider Conothele chinnarensis sp.nov.is described from Chinnar Wildlife Sanctuary in Western Ghats of Kerala,India based on morphological characters.The new species C.chinnarensis sp.nov.resembles C.varvarti,C.birmanica and C.vali but can be distinguished from C.varvarti by the long stalk of the apical lobe which is not distally twisted,whereas in C.varvarti,the stalk is twisted distally and the burrow in C.chinnarensis sp.nov.is straight without any other chamber,while in C.varvarti,on the inner end of the burrow a second D-shaped hinged trapdoor exists,which opens into another chamber(Siliwal et al.,2009);it differs from C.birmanica by the presence of curved spines on tibiaeⅢwhich are absent in C.birmanica. 展开更多
关键词 Conothele mygalomorph spiders trapdoor spiders tarantulas Western Ghats
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分布式多线程Spider的设计与实现
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作者 陈静 《现代计算机》 2009年第10期171-173,共3页
搜索引擎已经是当今从浩瀚的网上资源获取信息的最快最方便的工具,因此也已成为计算机工业界和学术界争相研究、开发的对象。Spider是搜索引擎的核心模块,通过设计一个分布式多线程Spider系统,在实验中得到较好的测试结果。
关键词 分布式 JAVA多线程 spider
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速派得:Spider搭建终端智能配送网——专访速派得CEO江镇
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作者 刘光琦 《中国储运》 2015年第7期70-71,共2页
将城市内的闲散运力整合,将拼车模式运用到物流领域,最终达到成本与效率的最优化,速派得探索的是移动互联网环境下的城市物流模式。江镇坦言,是2010年开始逐渐火热的易到用车模式给了他一个可行的落地配解决思路,他开始尝试把这一模式... 将城市内的闲散运力整合,将拼车模式运用到物流领域,最终达到成本与效率的最优化,速派得探索的是移动互联网环境下的城市物流模式。江镇坦言,是2010年开始逐渐火热的易到用车模式给了他一个可行的落地配解决思路,他开始尝试把这一模式应用到干线终端上。经过调试,一个整合社会闲散运力,通过智能路由实现多点取送的物流模式逐渐清晰。 展开更多
关键词 派得 CEO spider 物流模式 江镇 最优化 上游企业 创新源 模式应用 平台服务
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SPIDER:机床行业电永磁吸盘的新强者——访瑞霆贸易(上海)有限公司SPIDER技术顾问安虎述
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作者 樊有海 《金属加工(冷加工)》 2013年第12期11-11,共1页
韩国SPIDER公司成立于2009年,专注于机床行业快速工装以及金属加工工艺的优化、注塑机和冲压机的模具与刀具的快速负载和卸载技术。
关键词 spider 机床行业 电永磁吸盘 技术 上海 贸易 金属加工工艺 快速工装
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基于Hi-Spider Router系统的校园VPN实现
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作者 刘艳霞 《电脑学习》 2010年第6期46-47,共2页
本文通过介绍VPN的概念和技术,提出了一种架设基于Hi-Spider Router路由系统SSL VPN服务器的方案,从而构建出高性价比的校园专用网。
关键词 VPN 校园 Hi-spiderRouter
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一种改进的T-Spider分布式爬虫 被引量:3
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作者 金凡 顾进广 《微电子学与计算机》 CSCD 北大核心 2011年第8期102-104,共3页
为了提高互联网网页的抓取速度,提出了一个改进的T-Spider分布式爬虫模型.该爬虫在解析URL阶段将页面进行切割以并行解析,在页面调度阶段使用改进的链接优先权计算方法,提高爬虫的抓取速度和稳定性.通过实验结果分析,验证了该方法的有效性.
关键词 网络爬虫 T-spider 页面切割 链接优先权计算
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