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Phenolic compounds affect production of pyocyanin, swarming motility and biofilm formation of Pseudomonas aeruginosa

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Asian Pacific Journal of Tropical Biomedicine 2016年第8期6卷 698-701页

作者： Aylin Ugurlu Aysegul Karahasan Yagci Seyhan Ulusoy Burak Aksu Gulgun Bosgelmez-Tinaz Department of Microbiology School of Medicine Marmara University Department of Biology Faculty of Arts and Sciences Süleyman Demirel University Department of Basic Pharmaceutical Sciences Faculty of Pharmacy Marmara University

Objective: To investigate the effects of plant-derived phenolic compounds(i.e. caffeic acid, cinnamic acid, ferulic acid and vanillic acid) on the production of quorum sensing regulated virulence factors such as pyocyanin, biofilm formation and swarming motility of Pseudomonas aeruginosa(P. aeruginosa) isolates.Methods: Fourteen clinical P. aeruginosa isolates obtained from urine samples and P. aeruginosa PA01 strain were included in the study. The antibacterial effects of phenolic compounds were screened by well diffusion assay. Pyocyanin and biofilm activity were measured from culture supernatants and the absorbance values were measured using a spectrophotometer. swarming plates supplemented with phenolic acids were point inoculated with P. aeruginosa strains and the ability to swarm was determined by measuring the distance of swarming from the central inoculation site.Results: Tested phenolic compounds reduced the production of pyocyanin and biofilm formation without affecting growth compared to untreated cultures. Moreover, these compounds blocked about 50% of biofilm production and swarming motility in P. aeruginosa isolates.Conclusions: We may suggest that if swarming and consecutive biofilm formation could be inhibited by the natural products as shown in our study, the bacteria could not attach to the surfaces and produce chronic infections. Antimicrobials and natural products could be combined and the dosage of antimicrobials could be reduced to overcome antimicrobial resistance and drug side effects.

关键词： Quorum sensing Phenolic compounds Pseudomonas aeruginosa Biofilm swarming

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Loader and Tester swarming Drones for Cellular PhoneNetwork Loading and Field Test: Non-stochasticParticle Swarm Optimization

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Journal of Autonomous Intelligence 2019年第2期2卷 14-24页

作者： Amir Mirzaeinia Mostafa Hassanalian Mohammad Shekaramiz Mehdi Mirzaeinia Department of Computer Science and Engineering New Mexico Inst.of Mining and Tech.SocorroNMUSA Department of Mechanical and Aerospace Engineering New Mexico Inst.of Mining and Tech.SocorroNMUSA Department of Electrical and Computer Engineering Utah State UniversityLoganUTUSA Department of Electrical Engineering Amirkabir University of TechnologyTehranIran

Cellular network operators have problems to test their network without affecting their user experience. Testingnetwork performance in a loaded situation is a challenge for the network operator because network performance differswhen it has more load on the radio access part. Therefore, in this paper, deploying swarming drones is proposed to loadthe cellular network and scan/test the network performance more realistically. Besides, manual swarming dronenavigation is not efficient enough to detect problematic regions. Hence, particle swarm optimization is proposed to bedeployed on swarming drone to find the regions where there are performance issues. swarming drone communicationshelps to deploy the particle swarm optimization (PSO) method on them. Loading and testing swarm separation help tohave almost non-stochastic received signal level as an objective function. Moreover, there are some situations that morethan one network parameter should be used to find a problematic region in the cellular network. It is also proposed toapply multi-objective PSO to find more multi-parameter network optimization at the same time.

关键词： Particle Swarm Optimization swarming Drone Cellular Network Radio Optimization Loaded Network Test

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基于流函数的多移动机器人swarming控制模型

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机器人 2006年第3期28卷 264-268,274页

作者：卢骏关治洪王华华中科技大学非线性与复杂系统研究中心湖北武汉430074

利用流函数解决单个移动机器人的避障问题,并提出了基于流函数和单一连接规则的、采用虚拟lead-er和二叉树结构的多移动机器人swarm ing控制模型.基于单一连接规则的二叉树结构使得整个机器人群的控制更简单,更灵活;而虚拟leader的引入... 详细信息

利用流函数解决单个移动机器人的避障问题,并提出了基于流函数和单一连接规则的、采用虚拟lead-er和二叉树结构的多移动机器人swarm ing控制模型.基于单一连接规则的二叉树结构使得整个机器人群的控制更简单,更灵活;而虚拟leader的引入,使机器人群在避障过程中不会发生分离,并能够很好地解决类似于机器人掉队的问题,提高了系统的稳定性,增强了系统的应变能力.仿真结果验证了该模型的有效性.

关键词：流函数多移动机器人 swarming 单一连接虚拟leader 二叉树

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Optimization Scheme Based on Differential Equation Model for Animal swarming

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Open Journal of Optimization 2013年第2期2卷 45-51页

作者： Takeshi Uchitane Atsushi Yagi Department of Information and Physical Sciences Osaka University Osaka Japan

This paper is devoted to introducing an optimization algorithm which is devised on a basis of ordinary differential equation model describing the process of animal swarming. By several numerical simulations, the nature of the optimization algorithm is clarified. Especially, if parameters included in the algorithm are suitably set, our scheme can show very good performance even in higher dimensional problems.

关键词： Optimization Scheme Differential Equation Model Animal swarming

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Natural Hybridization between Rhododendron delavayi and R.cyanocarpum(Ericaceae),from Morphological,Molecular and Reproductive Evidence

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Journal of Integrative Plant Biology 2010年第9期52卷 844-851页

作者： Yong-Peng Ma Chang-Qin Zhang Jing-Li Zhang Jun-Bo Yang Kunming Botanic Garden Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China Key Laboratory of Resource Plants and Biotechnology Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China Graduate University of Chinese Academy of Sciences Chinese Academy of Sciences Beijing 100049 China Tunnan Agricultural University Kunming 650201 China Key Laboratory of Biodiversity and Biogeography Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China

The natural hybridization that occurs between two sympatric species of Rhododendron subgenus Hymenanthes in Yunnan, China, was investigated. In field observations, it was noted that the putative hybrids between R. delavayi Franch. and R. cyanocarpum （Franch.） Franch. ex W.W. Sm. had intermediate morphologies. On the basis of morphology, chloroplast DNA （trnL-rp132） and nuclear DNA （waxy）, hybrids and parental species were identified. Hybridization occurred in both directions, but was asymmetrical, with R. delavayi as the major maternal parent. Reciprocal hand pollination treatments showed that either species, as pollen donor or pollen receiver, could produce fruits. It was noted that fruit set varied among treatments. The same pollinators （bumblebees） were shared in both parental species. From these results, we conclude that individuals with intermediate morphologies are indeed of hybrid origin from natural hybridization between R. cyanocarpum and R. delavayi. Furthermore, we presume the hybridization at the study site could have been initiated by habitat disturbance in the 1950s, and we may hence witness the early stages of hybrid swarm formation.

关键词： Natural hybridization Hybridization Hybrids Species Fruits DNA Fruit swarming Pollen Pollinators

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多移动机器人swarming协调控制研究

多移动机器人Swarming协调控制研究

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作者：卢骏华中科技大学

学位级别：硕士

近年来,多移动机器人协调控制问题逐渐成为机器人学中的研究热点。其中,多移动机器人swarming控制更是受到极大关注。这源于自然界中存在着大量的swarm,如昆虫、鸟群、鱼群等。可以预见多移动机器人swarming控制模型的研究成果在军事及... 详细信息

近年来,多移动机器人协调控制问题逐渐成为机器人学中的研究热点。其中,多移动机器人swarming控制更是受到极大关注。这源于自然界中存在着大量的swarm,如昆虫、鸟群、鱼群等。可以预见多移动机器人swarming控制模型的研究成果在军事及民用领域拥有巨大的市场潜力和应用前景。本论文就多移动机器人的swarming控制问题从单移动机器人的控制和移动机器人的群行为两个层次展开研究。首先在单移动机器人层次上,利用流函数解决单个移动机器人的避障问题,避免了人工势场法局部最小的问题。并给出了流线仿真图形,分析讨论了流函数法的一般拓展。其次,在群的层次上,首先讨论了swarm的一种特殊情况:flock。介绍了flock的基本理论,提出了引入虚拟leader的flock的模型并推导出了控制规律,虚拟leader的引入能保证flock群的有序性,并提高了系统的容错能力。然后研究了基于动态连接规则的swarming控制模型。在采用流函数解决单移动机器人避障的基础上,通过借鉴基于动态连接规则的多移动机器人swarming控制,提出了基于单一连接规则的有虚拟leader和二叉树结构的控制模型。基于单一连接规则的二叉树结构使得整个机器人群的控制更简单,更灵活;而虚拟leader的引入,使在避障过程中机器人群不会发生分离,并能够很好的解决类似于机器人掉队的问题,提高了系统的稳定性,增强了系统的应变能力。最后,对上述多移动机器人swarming控制模型进行了仿真实验,并对仿真结果进行了分析,提出了相应的问题。实验结果表明了本论文提出的flock的模型控制规律的正确性和swarm的模型的可行性和有效性。

关键词：多移动机器人流函数 swarming flocking 虚拟leader 单一连接

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Las-like quorum-sensing system negatively regulates both pyoluteorin and phenazine-1-carboxylic acid production in Pseudomonas sp. M18

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Science China(Life Sciences) 2008年第2期51卷 174-181页

作者： CHEN Yun, WANG XiaoLei, HUANG XianQing, ZHANG XueHong & XU YuQuan Key Laboratory of Microbial Metabolism of Ministry of Education, College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China Key Laboratory of Microbial Metabolism of Ministry of Education College of Life Sciences and Biotechnology Shanghai Jiao Tong University Shanghai China

A las-like quorum-sensing system in Pseudomonas sp. M18 was identified, which consisted of lasI and lasR genes encoding LuxI-LuxR type regulator. Several functions of the las system from strain M18 were investigated in this study. The chromosomal inactivation of either lasI or lasR by recombination increased the production of both pyoluteorin (Plt) and phenazine-1-carboxylic acid (PCA) by 4-5 fold and 2-3 fold over that of the wild type strain of M18, respectively. Production of both antibiotics was restored to wild-type levels after in trans complementation with the wild-type lasI or lasR gene. Expression of the translational fusions pltA'-'lacZ and phzA'-'lacZ further confirmed the negative effect of lasI or lasR on both biosynthetic operons, and it was also demonstrated that the las system was related to the ability of swarming motility and the inhibition of cell growth.

关键词： las system phenazine-1-carboxylic acid pyoluteorin swarming Pseudomonas sp. M18

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A review of jellyfish aggregations, focusing on India’s coastal waters

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Ecological Processes 2020年第1期9卷 689-697页

作者： Sanjiba Kumar Baliarsingh Aneesh Anandrao Lotliker Suchismita Srichandan Alakes Samanta Nimit Kumar T.M.Balakrishnan Nair Indian National Centre for Ocean Information Services Ministry of Earth SciencesGovt.of IndiaHyderabad 500090India

A review of jellyfish aggregations focused on India’s coastal waters was conducted,with the aim to enhance understanding of conducive conditions and subsequent ecological impacts.Jellyfish swarming,as well as their beach strandings,have been reported from many areas of the world—including India’s coastal waters.A variety of natural(winds,tidal fronts,surface currents,water temperature,salinity,turbidity,dissolved oxygen)and anthropogenic(water quality deterioration,overfishing,translocation,habitat modification)factors play pivotal roles in triggering jellyfish aggregations.Jellyfish aggregation events in the forms of their swarming in coastal waters and beach strandings have resulted in ephemeral nuisances such as water quality deterioration,food chain alterations,hindrance in seawater uptake by power plants,clogging of nets during fishing operations,and tourism declines.Several well-known Indian tourist beaches(e.g.,Puri,Chennai,Goa,and Mumbai)have experienced beach strandings.Despite recurrence of such events,jellyfishes are relatively less scientifically investigated and monitored in Indian coastal waters.Therefore,it is important to determine the environmental conditions that trigger jellyfish swarming,in order to develop effective monitoring and prediction strategies.This study additionally proposes a conceptual framework towards development of a jellyfish monitoring system for Indian waters using satellite and model data.

关键词： Jellyfish swarming Coast Water quality Bay of Bengal Arabian Sea

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高效内容分布网络设计与实现

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计算机工程 2006年第4期32卷 106-108页

作者：王峰钱华林中科院计算机网络信息中心

结合CDN和P2P两种不同网络结构的优点,改善传统内容分布网络拓扑结构,使用基于无比率限制纠错码技术改进swarming传输协议,给出了一种高效内容分布网络设计。介绍了该内容分布网络的系统结构及相关关键技术等方面内容,以及这种新内容分... 详细信息

结合CDN和P2P两种不同网络结构的优点,改善传统内容分布网络拓扑结构,使用基于无比率限制纠错码技术改进swarming传输协议,给出了一种高效内容分布网络设计。介绍了该内容分布网络的系统结构及相关关键技术等方面内容,以及这种新内容分布网络的特性。

关键词： P2P CDN swarming FEC 无比率限制纠错码

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Into the life and death: RecA a WISE factor working to integrate survival and evolution in <i>Escherichia coli</i>

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Advances in Bioscience and Biotechnology 2013年第3期4卷 442-449页

作者： José María Gómez Gómez Museo de la Naturaleza de Cantabria Plaza Don Pedro Ygareda Cantabria Spain

Escherichia coli RecA has been considered traditionally a cellular protein with multiple vital functions working to ensure the maintenance of integrity of genome in each individual bacterial cell as well as promoting swarming migration in collectivity. On the contrary, recently it has been described that RecA promotes cellular apoptotic-like death (ALD), a pathway of programmed cellular death (PCD). In fact, RecA has been dubbed as the major apoptotic executor in E. coli. From these studies, RecA emerges as a prototypical Gin/Gan protein that despite of their intrinsic vital and lethal anfi-funcionality becomes in a WISE factor: a Worker to Integrate Survival and Evolution in E. coli evolving populations living in community. Here, I provide a review of recent experimental and conceptual advances trying to understand these RecA’s antagonistic roles in appearance contradictory under a unified biological vision.

关键词： Life & Death E. coli RecA RecA Nucleofilament RecA RecA Anfi-Funcionality SOS Response Apoptosis-Like Death swarming Motility Multicellularity Sociability Cheaters Cooperation WISE Factor

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