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Enhanced Security with Improved Defensive Routing Mechanism in Wireless Sensor Networks
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作者 R.Sabitha C.Gokul Prasad S.Karthik 《Computer Systems Science & Engineering》 SCIE EI 2023年第6期2795-2810,共16页
In recent scenario of Wireless Sensor Networks(WSNs),there are many application developed for handling sensitive and private data such as military information,surveillance data,tracking,etc.Hence,the sensor nodes of W... In recent scenario of Wireless Sensor Networks(WSNs),there are many application developed for handling sensitive and private data such as military information,surveillance data,tracking,etc.Hence,the sensor nodes of WSNs are distributed in an intimidating region,which is non-rigid to attacks.The recent research domains of WSN deal with models to handle the WSN communications against malicious attacks and threats.In traditional models,the solution has been made for defending the networks,only to specific attacks.However,in real-time applications,the kind of attack that is launched by the adversary is not known.Additionally,on developing a security mechanism for WSN,the resource constraints of sensor nodes are also to be considered.With that note,this paper presents an Enhanced Security Model with Improved Defensive Routing Mechanism(IDRM)for defending the sensor network from various attacks.Moreover,for efficient model design,the work includes the part of feature evaluation of some general attacks of WSNs.The IDRM also includes determination of optimal secure paths and Node security for secure routing operations.The performance of the proposed model is evaluated with respect to several factors;it is found that the model has achieved better security levels and is efficient than other existing models in WSN communications.It is proven that the proposed IDRM produces 74%of PDR in average and a minimized packet drop of 38%when comparing with the existing works. 展开更多
关键词 Enhanced security model wireless sensor networks improved defensive routing mechanism secure paths node security
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Pneumonia with parapneumonic eff usion due to Fusobacterium necrophorum: a case report
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作者 Xiaojun Dong Qian Li +2 位作者 Anquan Zhu Xiaocui Wu Xuejie Wu 《World Journal of Emergency Medicine》 2025年第5期516-518,共3页
Fusobacterium is a genus of obligate anaerobic gram-negative bacilli that usually colonize the oropharynx,gastrointestinal tract,upper respiratory tract,and vaginal mucosa of humans as a part of the normal flora.[1,2]... Fusobacterium is a genus of obligate anaerobic gram-negative bacilli that usually colonize the oropharynx,gastrointestinal tract,upper respiratory tract,and vaginal mucosa of humans as a part of the normal flora.[1,2]Infections may occur once host defense mechanisms are altered and mucosal barriers are disrupted.[3]The clinical spectrum is wide and includes pharyngitis,sinusitis,abscess formation,puerperal infections,bacteremia,and septic shock.Within this genus,two species are most commonly isolated:Fusobacterium nucleatum and Fusobacterium necrophorum(F.necrophorum).F.necrophorum is usually associated with Lemierre’s syndrome,[4,5]a type of septic thrombophlebitis of the internal jugular vein. 展开更多
关键词 lemierre s syndrome host defense mechanisms PNEUMONIA fusobacterium necrophorum parapneumonic effusion mucosal barriers disrupted vaginal mucosa
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A Mini Review on Plant Immune System Dynamics:Modern Insights into Biotic and Abiotic Stress
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作者 Malini Ray Sanchari Burman Shweta Meshram 《Phyton-International Journal of Experimental Botany》 2025年第8期2285-2312,共28页
Plants are under constant exposure to varied biotic and abiotic stresses,which significantly affect their growth,productivity,and survival.Biotic stress,caused by pathogens,and abiotic stress,including drought,salinit... Plants are under constant exposure to varied biotic and abiotic stresses,which significantly affect their growth,productivity,and survival.Biotic stress,caused by pathogens,and abiotic stress,including drought,salinity,extreme temperatures,and heavy metals,activate overlapping yet distinct immune pathways.These are comprised of morphological barriers,hormonal signaling,and the induction of stress-responsive genes through complex pathways mediated by reactive oxygen species(ROS),phytohormones,and secondary metabolites.Abiotic stress triggers organelle-mediated retrograde signaling from organelles like chloroplasts and mitochondria,which causes unfolded protein responses and the regulation of cellular homeostasis.Simultaneously,biotic stress activates both PAMP-triggered immunity(PTI)and effector-triggered immunity(ETI),mediated by salicylic acid(SA),jasmonic acid(JA),and ethylene(ET).This review aims to provide an integrated overview of plant immune responses tomultiple stressors,with emphasis on molecular crosstalk and recent technological interventions.A systematic literature search was conducted using the Scopus database,covering studies published between 2010 and 2025.Advances in CRISPR-Cas genome editing,RNA interference,omics technologies,nanotechnology,and artificial intelligence have improved our knowledge of plant stress physiology and facilitated the design of resilient crop varieties.Despite these advances,the integration of immune signals under simultaneous biotic and abiotic stress remains poorly understood,particularly at tissue-specific and cellular levels.Additionally,practical challenges persist in delivery methods,regulatory hurdles,and long-term field validation.With the escalation of climate change,understanding the complex crosstalk between stress signalling pathways is essential formaintaining sustainable agriculture and global food security.Future directions point toward real-time monitoring tools,such as single-cell omics and spatial transcriptomics,to fine-tune immune responses and support precision crop improvement. 展开更多
关键词 Plant stress responses defense mechanisms signaling pathways biotic stress abiotic stress sustainable agriculture
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DEFENSE MECHANISMS OF URINARY BLADDER:STUDIES ON ANTIMICROBIAL POLYPEPTIDES FROM BLADDER MUCOSA 被引量:1
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作者 吴琦 王伯瑶 《Chinese Medical Sciences Journal》 CAS CSCD 1999年第1期17-22,共6页
The acid soluble extract of the bladder mucosal surface was obtained by washing out the bladder with dilute acetic acid in the presence of protease inhibitors. The wash out materials from... The acid soluble extract of the bladder mucosal surface was obtained by washing out the bladder with dilute acetic acid in the presence of protease inhibitors. The wash out materials from rats, rabbits, pigs, and humans manifested strong bactericidal activity against E.coli in vitro. The ultrafiltrate of the human material, which contained two major peptides with apparent molecular masses of 6 7 kD and 8 5 kD, respectively, showed potent bactericidal activity against E. coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus sanguis.Three antibacterial polypeptides (PiBPs) were purified from the porcine material. The molecular masses of PiBP 5, PiBP 11 and PiBP 25 were 5773.3 Da, 11127.8 Da and 25073 Da, respectively. PiBP 5 was unusually rich in glycine, serine and threonine residues(20 0, 16 3 and 10 4 mo1%, respectively), and N terminal amino acid sequencing revealed that PiBP 5 was homologous (83 3% identity in an 18 residue overlay) to the “tail” of human cytokeratin 7. Although the amino acid compositions of PiBP 11 and PiBP 25 were established, both had blocked N termini and primary sequence data were not obtained. These results provided evidence indicating that the presence of peptides in the bladder mucosa could enable it to kill adherent bacteria. 展开更多
关键词 urinary bladder defense mechanisms antimicrobial polypeptides
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Amino Acid and Fatty Acid Profile in Epidermal Mucus of Bluestreak Cleaner Wrasse (Labroides dimidiatus): Possible Role as Defense Mechanism against Pathogens
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作者 Maziidah Ab Rahman Roslan Arshad +1 位作者 Faizah Shaharom Nur Asma Ariffin 《Journal of Life Sciences》 2012年第12期1371-1377,共7页
Labroides dimidiatus has been proven to remove ectoparasites and monogeneans from client fishes and studies showed that they were not infected with the parasite. Due to this, there is a possibility that a defense mech... Labroides dimidiatus has been proven to remove ectoparasites and monogeneans from client fishes and studies showed that they were not infected with the parasite. Due to this, there is a possibility that a defense mechanism against pathogen and parasitic invasion exist in the epidermal mucus which serves as a mechanical as well as biochemical barrier. The study was performed to identify the amino acid and fatty acid components using GC (gas chromatography) and HPLC (high performance liquid chromatography) in epidermal mucus ofL. dimidiatus. The present study revealed 16 components of amino acid and 22 types of fatty acid in epidermal mucus ofL. dimidiatzts. Linoleic acid (C18:2n6c) was the most prominent PUFA (polyunsaturated fatty acid) which contributed approximately 11.69% of total fatty acids. The other major fatty acids are palmitic acid (C 16:0), oleic acid (C 18: l n9c), linoledaidic acid (C18:2n6t), arachidic acid (C20:0), Gamma-Linoleic acid (C18:3n6) and gadoleic acid (C20:1) which contained reasonable amounts of 9.52%, 8.06%, 6.26%, 8.33%, 6.21% and 9.05% of total fatty acids, respectively. This present study also demonstrated the presence of various amino acids in skin extract. Glycine, glutamine, arginine, asparagin and alanine were found at high concentration of 8.09%, 6.95%, 5.73%, 4.74%, 4.58% respectively. The most abundance percentage of linoleic acid (C18:2n6c) was found to be the metabolic precursor of arachidonic acid (AA) which inducing platelet aggregation, facilitate the blood clotting process and adhesion in endothelial cells during wound healing and might be responsible for rapid tissue growth in L. dimidiatus. It can be concluded that the amino acid and fatty acid profile from the epidermal mucus ofL. dimidiatus contains most of the essential components required to play a possible role in its defense mechanism. Understanding the biochemical properties of L. dimidiatus epidermal mucus in defense mechanism would enable to determine how this fish protect itself from parasitic infection. 展开更多
关键词 Labroides dimidiatus defense mechanism amino acid fatty acid epidermal mucus.
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The Study on Multinational Operation Risk-Defense System Based on Corporate Governance Mechanism
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作者 Hui Xu Yao Wang 《Chinese Business Review》 2003年第4期67-75,共9页
:With the unceasing globalization development of MNCs' business and connnuous intensify in international competition, the managers of MNCs find that the strategy decisions they are faced on are becoming more compli... :With the unceasing globalization development of MNCs' business and connnuous intensify in international competition, the managers of MNCs find that the strategy decisions they are faced on are becoming more complicated, and they have deeply realized that the perception and defense of the international risk has the impact on their strategy decisions. The thesis, proceeding with analyzing and evaluating risk types in the course of enterprises developing in the international markets, based on the integration international risk perception model, utilizing relative theories and study thoughts of the corporate governance mechanisms, especially the relative studies on overseas enterprises' governance mechanisms, explores how to use the corporate governance mechanisms to build the defense system against international risks. Meanwhile, the thesis further discusses the risks our native enterprises have suffered from during the multinational operation in detail, explores its reasons and offers the defense measures of all sorts of risk. 展开更多
关键词 multinational operation international risk perception corporate governance mechanisms risk defense
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Research on the Influence of Different Psychological Defense Mechanisms on the Psychology of Students
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作者 Qingfeng Tang Jinlin Peng 《Journal of Contemporary Educational Research》 2022年第5期14-20,共7页
The contradiction between id and ego is the root cause of various problems in the growth process of students.On the basis of understanding the functions of different psychological defense mechanisms,teachers can assis... The contradiction between id and ego is the root cause of various problems in the growth process of students.On the basis of understanding the functions of different psychological defense mechanisms,teachers can assist students in dealing with all areas of inner conflict and thus achieve a balanced state.Psychological defense mechanism is one of the means for individuals to deal with setbacks and anxiety.It plays an important role in preserving an individual's mental health.This paper mainly analyzes the impact of different types of psychological defense mechanisms in the growth process of students and discusses its importance as well as its significance.Finally,by analyzing its influencing factors,this paper also proposes strategies for adjusting the psychological defense mechanism,so as to provide reference for teachers in the practical education process. 展开更多
关键词 Psychological defense mechanism Id and ego Psychological balance Conflict and contradiction
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Double Prevention Mechanism of Chemical Safety Management Innovation
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作者 QIN Chenghu CHENG Yong 《外文科技期刊数据库(文摘版)工程技术》 2021年第3期242-247,共6页
In order to ensure the safe and reliable development of chemical production, it is necessary to strengthen safety control, establish a special scientific double prevention mechanism, reduce the probability of all kind... In order to ensure the safe and reliable development of chemical production, it is necessary to strengthen safety control, establish a special scientific double prevention mechanism, reduce the probability of all kinds of safety accidents, so that the comprehensive benefits of chemical enterprises in the process of production, operation and construction can be fundamentally improved. In view of this, this paper analyzes the significance of chemical safety management, designs the construction scheme of dual defense mechanism of chemical safety management, and finally puts forward the key points of dual defense mechanism of chemical safety management, in order to provide theoretical help for related staff. 展开更多
关键词 dual defense mechanism chemical safety management INNOVATION
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Dual Instinct and Structural Theories: DSM-5-TR
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作者 Lawrence Greenman 《Open Journal of Psychiatry》 2024年第4期374-379,共6页
The genetic based Dual Instinct Theory is determined by evolutionary history. Aggression is required for survival and sex for propagation of species. Aggressive and sexual drive derivatives with their corresponding de... The genetic based Dual Instinct Theory is determined by evolutionary history. Aggression is required for survival and sex for propagation of species. Aggressive and sexual drive derivatives with their corresponding defence mechanisms are combined with biologically based stages of infant/child development and the functional entity of Structural Theory. This model of human nature is the applied to the diagnostic categories of DSM-5-TR. Objectives: To follow the innate Dual Instinct Theory from life to death and through Artificial Intelligence;connect it with biological stages of development of the Structural Theory and illustrate its manifestations in DSM-5-TR classifications. Method: Review of selected published literature. Applying the principle of focus and cognition of informed clinical observation of innate drive derivatives in conjunction with The Structural Theory. Both theories are functional entities with no structures involved. Sigmund Freud’s biologically based stages of development;oral, anal, genital pubic, adult, and geriatric along with a variety of unconscious, automatic, and persistent defense mechanisms are selectively folded into diagnosis listed in the manual. 展开更多
关键词 Dual Instincts Structural Theory Stages of Development Drive Derivatives mechanisms of Defense
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Activation and suppression mechanisms of theNRG1 helper NLRs
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作者 Yu‐Ru Wang Ruize Zhang +2 位作者 Daowen Wang Yong Wang Zheng Qing Fu 《Journal of Integrative Plant Biology》 2025年第8期1985-1987,共3页
Plants developed a sophisticated defense mechanism to safeguard themselves from a diverse range of pathogens,including fungi,oomycetes,bacteria,viruses,and nematodes.They utilize specific receptors to recognize these ... Plants developed a sophisticated defense mechanism to safeguard themselves from a diverse range of pathogens,including fungi,oomycetes,bacteria,viruses,and nematodes.They utilize specific receptors to recognize these threats.Initially,plants rely on pattern recognition receptors located on their cell surfaces to identify conserved molecules referred to as pathogen-associated molecular patterns(PAMPs),which triggers PAMPs-triggered immunity(PTI).However,adapted pathogens evolve to deliver effector proteins into host cells to counteract PTI,leading to effector-triggered susceptibility.In response,plants have acquired intracellular nucleotide-binding leucine-rich repeat(NLR)receptors to detect these effector proteins and activate effector-triggered immunity(ETI)against avirulent pathogens. 展开更多
关键词 pattern recognition receptors effector proteins SUPPRESSION defense mechanism NRG plant defense ACTIVATION cell surfaces
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Adaptive Multi-Layer Defense Mechanism for Trusted Federated Learning in Network Security Assessment
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作者 Lincong Zhao Liandong Chen +3 位作者 Peipei Shen Zizhou Liu Chengzhu Li Fanqin Zhou 《Computers, Materials & Continua》 2025年第12期5057-5071,共15页
The rapid growth of Internet of things devices and the emergence of rapidly evolving network threats have made traditional security assessment methods inadequate.Federated learning offers a promising solution to exped... The rapid growth of Internet of things devices and the emergence of rapidly evolving network threats have made traditional security assessment methods inadequate.Federated learning offers a promising solution to expedite the training of security assessment models.However,ensuring the trustworthiness and robustness of federated learning under multi-party collaboration scenarios remains a challenge.To address these issues,this study proposes a shard aggregation network structure and a malicious node detection mechanism,along with improvements to the federated learning training process.First,we extract the data features of the participants by using spectral clustering methods combined with a Gaussian kernel function.Then,we introduce a multi-objective decision-making approach that combines data distribution consistency,consensus communication overhead,and consensus result reliability in order to determine the final network sharing scheme.Finally,by integrating the federated learning aggregation process with the malicious node detection mechanism,we improve the traditional decentralized learning process.Our proposed ShardFed algorithm outperforms conventional classification algorithms and state-of-the-art machine learning methods like FedProx and FedCurv in convergence speed,robustness against data interference,and adaptability across multiple scenarios.Experimental results demonstrate that the proposed approach improves model accuracy by up to 2.33%under non-independent and identically distributed data conditions,maintains higher performance with malicious nodes containing poisoned data ratios of 20%–50%,and significantly enhances model resistance to low-quality data. 展开更多
关键词 Trusted federated learning adaptive defense mechanism network security assessment participant trustworthiness scoring hybrid anomaly detection
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A Novel Distributed LDoS Attack Scheme against Internet Routing 被引量:3
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作者 ZHU Hongliangt XIN Yang +1 位作者 WU Qiuxin YOU Fucheng 《China Communications》 SCIE CSCD 2014年第A01期101-107,共7页
LDoS (Low-rate Denial of Service) attack, exploiting the flaws in the congestion avoidance mechanism of TCP protocol,is periodic, stealthy, and with high efficiency. Since BGP uses TCP as a transport protocol, it is... LDoS (Low-rate Denial of Service) attack, exploiting the flaws in the congestion avoidance mechanism of TCP protocol,is periodic, stealthy, and with high efficiency. Since BGP uses TCP as a transport protocol, it is subject to LDoS attacks as well. LDoS attacks can cause table reset, route flapping of BGP protocol. A deliberately constructed distributed low-rate DOS attacks can even generate surge of updates throughout the Internet. In this paper, we investigate the promotion of attack efficiency of this novel attack, and then propose an attack model to simulate the LDoS attack. Experiments prove that this attack model can exponentially lower the attack costs and improve the attack effect. 展开更多
关键词 distributed low-rate DoS attacks attack efficiency BGP route flapping defense mechanisms
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Ozone disrupts the communication between plants and insects in urban and suburban areas:an updated insight on plant volatiles 被引量:2
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作者 Noboru Masui Evgenios Agathokleous +3 位作者 Tomoki Mochizuki Akira Tani Hideyuki Matsuura Takayoshi Koike 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第4期1337-1349,共13页
Plant-insect interactions are basic components of biodiversity conservation.To attain the international Sustainable Development Goals(SDGs),the interactions in urban and in suburban systems should be better understood... Plant-insect interactions are basic components of biodiversity conservation.To attain the international Sustainable Development Goals(SDGs),the interactions in urban and in suburban systems should be better understood to maintain the health of green infrastructure.The role of ground-level ozone(0_(3)) as an environmental stress disrupting interaction webs is presented.Ozone mixing ratios in suburbs are usually higher than in the center of cities and may reduce photosynthetic productivity at a relatively higher degree.Consequently,carbon-based defense capacities of plants may be suppressed by elevated 0_(3) more in the suburbs.However,contrary to this expectation,grazing damages by leaf beetles have been severe in some urban centers in comparison with the suburbs.To explain differences in grazing damages between urban areas and suburbs,the disruption of atmospheric communication signals by elevated 0_(3) via changes in plant-regulated biogenic volatile organic compounds and long-chain fatty acids are considered.The ecological roles of plant volatiles and the effects of 0_(3) from both a chemical and a biological perspective are presented.Ozone-disrupted plant volatiles should be considered to explain herbivory phenomena in urban and suburban systems. 展开更多
关键词 Biological interactions Elevated O_3 Insect grazing POLLINATION Plant defense mechanisms
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Differences in pectoral fin spine morphology between vocal and silent clades of catfishes (Order Siluriformes): Ecomorphological implications 被引量:1
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作者 Ingrid M.KAATZ Donald J.STEWART +1 位作者 Aaron N.RJCE Phillip S.LOBEL 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第1期73-89,共17页
Stridulatory sound-producing behavior is widespread across catfish families, but some are silent. To understand why, we compared spine morphology and ecotype of silent and vocal clades. We determined vocal ability of ... Stridulatory sound-producing behavior is widespread across catfish families, but some are silent. To understand why, we compared spine morphology and ecotype of silent and vocal clades. We determined vocal ability of laboratory specimens during disturbance behavior. Vocal families had bony (not flexible or segmented) spines, well-developed anterior and/or posterior serrations, and statistically significantly longer spines. We compared morphology of the proximal end of the pectoral spine between vocal and silent species. For vocal taxa, microscopic rounded or bladed ridges or knobs were present on the dorsal process. Most silent species had reduced processes with exclusively smooth, convoluted, or honeycombed surfaces very similar to spine-locking surfaces, or they had novel surfaces (beaded, vacuolated, cobwebbed). Most callichthyids had ridges but many were silent during disturbance. All doradid, most auchenipterid and most mochokid species were vocal and had ridges or knobs. Within the Auchenipteridae, vocal species had spines with greater weight and serration development but not length. Silent auchenipterids had thin, brittle, distally segmented spines with few microscopic serrations on only one margin and a highly reduced dorsal process lacking any known vocal morphology. Silent auchenipterids are derived and pelagic, while all vocal genera are basal and benthopelagic. This is the first phylogenetic evidence for stridulation mechanism loss within catfishes. Phylogenetic mapping of vocal ability, spine condition, and ecotype revealed the repeated presence of silence and vocal taxa, short and long spines, and ecotype shifts within clades. The appearance and loss of vocal behavior and supporting morphologies may have facilitated diversification among catfishes [Current Zoology 56 (1): 73 89 2010]. 展开更多
关键词 Bioacoustic Defense mechanisms Historical biology STRIDULATION
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DDoS Attack in Software Defined Networks: A Survey 被引量:1
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作者 XU Xiaoqiong YU Hongfang YANG Kun 《ZTE Communications》 2017年第3期13-19,共7页
Distributed Denial of Service(DDoS) attacks have been one of the most destructive threats to Internet security. By decoupling the network control and data plane, software defined networking(SDN) offers a flexible netw... Distributed Denial of Service(DDoS) attacks have been one of the most destructive threats to Internet security. By decoupling the network control and data plane, software defined networking(SDN) offers a flexible network management paradigm to solve DDoS attack in traditional networks. However, the centralized nature of SDN is also a potential vulnerability for DDo S attack. In this paper, we first provide some SDN-supported mechanisms against DDoS attack in traditional networks. A systematic review of various SDN-self DDo S threats are then presented as well as the existing literatures on quickly DDoS detection and defense in SDN. Finally, some promising research directions in this field are introduced. 展开更多
关键词 software defined networks SDN security DDOS detection method defense mechanism
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Application of ferrous sulfate alleviates negative impact of cadmium in rice(Oryza sativa L.)
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作者 JAVARIA AFZAL XIUKANG WANG +11 位作者 MUHAMMAD HAMZAH SALEEM XUECHENG SUN SHAHID HUSSAIN IMRAN KHAN MUHAMMAD SHOAIB RANA SHAKEEL AHMED SAMRAH AFZAL AWAN SAJID FIAZ OMAR AZIZ KASHIF ALI KUBAR SHAFAQAT ALI CHENGXIAO HU 《BIOCELL》 SCIE 2021年第6期1631-1649,共19页
Soil contamination with toxic heavy metals[such as cadmium(Cd)]is becoming a serious global problem due to rapid development of social economy.Iron(Fe),being an important element,has been found effective in enhancing ... Soil contamination with toxic heavy metals[such as cadmium(Cd)]is becoming a serious global problem due to rapid development of social economy.Iron(Fe),being an important element,has been found effective in enhancing plant tolerance against biotic and abiotic stresses.The present study investigated the extent to which different levels of Ferrous sulphate(FeSO_(4))modulated the Cd tolerance of rice(Oryza sativa L.),when maintained in artificially Cd spiked regimes.A pot experiment was conducted under controlled conditions for 146 days,by using natural soil,mixed with different levels of CdCl_(2)[0(no Cd),0.5 and 1 mg/kg]together with the exogenous application of FeSO_(4) at[0(no Fe),1.5 and 3 mg/kg]levels to monitor different growth,gaseous exchange characteristics,oxidative stress,antioxidative responses,minerals accumulation,organic acid exudation patterns of O.sativa.Our results depicted that addition of Cd to the soil significantly(P<0.05)decreased plant growth and biomass,gaseous exchange parameters,mineral uptake by the plants,sugars(soluble,reducing,and non-reducing sugar)and altered the ultrastructure of chloroplasts,plastoglobuli,mitochondria,and many other cellular organelles in Cd-stressed O.sativa compared to those plants which were grown without the addition of Cd in the soil.However,Cd toxicity boosted the production of reactive oxygen species(ROS)by increasing the contents of malondialdehyde(MDA),which is the indication of oxidative stress in O.sativa and was also manifested by hydrogen peroxide(H_(2)O_(2))contents and electrolyte leakage to the membrane bounded organelles.Although,activities of various antioxidative enzymes like superoxidase dismutase(SOD),peroxidase(POD),catalase(CAT)and ascorbate peroxidase(APX)and non-enzymatic antioxidants like phenolics,flavonoid,ascorbic acid,anthocyanin and proline contents increased up to a Cd level of 0.5 mg/kg in the soil but were significantly diminished at the highest Cd level of 1 mg/kg in the soil compared to those plants which were grown without the addition of Cd in the soil.The negative impacts of Cd injury were reduced by the application of FeSO_(4) which increased plant growth and biomass,improved photosynthetic apparatus,antioxidant enzymes,minerals uptake together with diminished exudation of organic acids as well as oxidative stress indicators in roots and shoots of O.sativa by decreasing Cd retention in different plant parts.These results shed light on the effectiveness of FeSO_(4) in improving the growth and upregulation of antioxidant enzyme activities of O.sativa in response to Cd stress.However,further studies at field levels are required to explore the mechanisms of FeSO_(4)-mediated reduction of the toxicity of not only Cd,but possibly also other heavy metals in plants. 展开更多
关键词 ANTIOXIDANTS Defense mechanism Heavy metals Iron Organic acids exudation
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Effects of Plant Extracts and Beauveria bassiana on the Activity of Defense-Related Enzymes in Solanum lycopersicum L.during Interaction with Fusarium oxysporum f.sp.lycopersici
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作者 JoséAdrian Perez-Robles Carlos Alberto Lecona-Guzmán +1 位作者 Víctor Manuel Ruíz-Valdiviezo Joaquín Adolfo Montes-Molina 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第9期2503-2518,共16页
The objective to this work was to evaluate the enzymatic activity in the culture of Solanum lycopersicum L.infected with Fusarium oxysporum after the combined application of Beauveria bassiana and plant extracts.Solan... The objective to this work was to evaluate the enzymatic activity in the culture of Solanum lycopersicum L.infected with Fusarium oxysporum after the combined application of Beauveria bassiana and plant extracts.Solanum lycopersicum plantlets were transplanted 15 days after the emergency.Five days after transplanting,Beauveria bassiana spores were applied at a concentration of 1×10^(7)spores mL^(−1)onto soil(along with A.indica(N)and P.auritum(H)leaf extracts)where S.lycopersicum plants were planted.Eight days after transplanting,spores of F.oxysporum strain were applied at a concentration of 1×10^(6)spores mL^(−1)to soil where S.lycopersicum plants were growing.The development of S.lycopersicum plants was monitored for 114 days,whereby a randomized complete block treatment design was used,the roots of the plants were crushed with liquid nitrogen,after which UV/VIS spectrophotometry was used to determine protein concentration,as well as the activity ofβ-1,3-glucanases,peroxidases(POX,EC1.11.1.7),catalase and chitinases.The treatments combining B.bassiana and A.indica and P.auritum extracts,had a significant difference in enzymatic activity levels,thus contributing to better defense mechanisms and a greater protection to S.lycopersicum plants in the presence of F.oxysporum.The application of B.bassiana and plant extracts to the ground mitigated damage caused by F.oxysporum on S.lycopersicum plants. 展开更多
关键词 Glucanases CHITINASES PEROXIDASES CATALASE defense mechanisms
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Changes in Phyto-Chemical Status upon Viral Infections in Plant:A Critical Review
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作者 Tehmina Bahar Adeeba Mahboob Qureshi +3 位作者 Fasiha Qurashi Muniba Abid Misbah Batool Zahra Muhammad Saleem Haider 《Phyton-International Journal of Experimental Botany》 SCIE 2021年第1期75-86,共12页
Most damaging plant diseases have been caused by viruses in the entire world.In tropical and subtropical areas,the damage caused by plant virus leads to great economic and agricultural losses.Single stranded DNA virus... Most damaging plant diseases have been caused by viruses in the entire world.In tropical and subtropical areas,the damage caused by plant virus leads to great economic and agricultural losses.Single stranded DNA viruses(geminiviruses)are the most perilous pathogens which are responsible for major diseases in agronomic and horticultural crops.Significantly begomoviruses and mastreviruses are the biggest genus of plant infecting viruses,transmitted though Bemisia tabaci and members of Cicadellidae respectively.Plants possesses some naturally existing chemicals term as phyto-chemicals which perform important functions in the plant.Some antioxidant enzymes are used by plants for selfdefense upon foreign invasion of infection.This review explains the present perceptive of influence of viral infections on phyto-chemicals,oxidative enzymes and biochemical changes occurring in the plant.Viral infection mediated phytochemical changes in plants mainly includes:up and down regulation of photosynthetic pigment,increase in the concentration of phenolic compounds,elevation of starch content in the leaf and up&down regulation of anti-oxidative enzymes including(GPX)guaiacol peroxidase,(PPO)polyphenol oxidase,(APX)ascorbate peroxidase,(SOD)superoxide dismutase and(CTA)catalase.These changes lead to initiation of hypersensitive response,by thicken of the leaf lamina,lignification under the leaf surface,blocking to stomatal openings,systematic cell death,generation of reactive oxidative species(ROS),activation of pathogen mediated resistance pathways i.e.,production of salicylic acid and jasmonic acid.Collectively all the physiological changes in the plant due to viral infection supports the activation of defense mechanism of the plant to combat against viral infection by limiting virus in specific area,followed with the production of barriers for pathogen,accumulation of starch in the leaf and excess production of(ROS).These strategies used by the plant to prevent the spread of virus in whole plant and to minimize the risk of severe yield loss. 展开更多
关键词 Anti-oxidative enzymes defense mechanism phyto-chemicals viral infection
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Continual Process of Self-Making: Hester Prynne's Life Is an Instance of Sublimation
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作者 U. H. Ruhina Jesmin 《Journal of Literature and Art Studies》 2012年第4期471-475,共5页
This paper attempts to demonstrate Hester Prynne's, in Nathaniel Hawthorne's romantic work of fiction The Scarlet Letter (1994), sublimation of her sexual impulses into identifying with the socially acceptable hum... This paper attempts to demonstrate Hester Prynne's, in Nathaniel Hawthorne's romantic work of fiction The Scarlet Letter (1994), sublimation of her sexual impulses into identifying with the socially acceptable humanitarian actions, and societal demands in order to avoid the confrontation with the scorn of the people of Boston, her sexual urge, and with her weakness. Hester's libidinal energy was channeled into socially approved activities in her self-devoted years that made up her identity and reality. The scarlet letter ceased to be a stigma which once attracted the world's scorn and bitterness, later looked upon with reverence, and transformed into a thing to be sorrowed over. She had not ignored a large part of reality of her life (the past and present). If she ignored her past she would entirely detach it from the present. She integrated her stigma into her life in the continual process of self-making, and thereby projecting herself into the future 展开更多
关键词 ADULTERY REALITY defense mechanism SUBLIMATION MEANING
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High-Resolution Disease Phenotyping Reveals Distinct Resistance Mechanisms of Tomato Crop Wild Relatives against Sclerotinia sclerotiorum
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作者 Severin Einspanier Christopher Tominello-Ramirez +3 位作者 Mario Hasler Adelin Barbacci Sylvain Raffaele Remco Stam 《Plant Phenomics》 CSCD 2024年第4期869-883,共15页
Besides the well-understood qualitative disease resistance,plants possess a more complex quantitative form of resistance:quantitative disease resistance(QDR).QDR is commonly defined as a partial but more durable form ... Besides the well-understood qualitative disease resistance,plants possess a more complex quantitative form of resistance:quantitative disease resistance(QDR).QDR is commonly defined as a partial but more durable form of resistance and,therefore,might display a valuable target for resistance breeding.The characterization of QDR phenotypes,especially of wild crop relatives,displays a bottleneck in deciphering QDR's genomic and regulatory background.Moreover,the relationship between QDR parameters,such as infection frequency,lag-phase duration,and lesion growth rate,remains elusive.High hurdles for applying modern phenotyping technology,such as the low availability of phenotyping facilities or complex data analysis,further dampen progress in understanding QDR.Here,we applied a low-cost(<1.000 €)phenotyping system to measure lesion growth dynamics of wild tomato species(e.g.,Solanum pennellii or Solanum pimpinellifolium).We provide insight into QDR diversity of wild populations and derive specific QDR mechanisms and their cross-talk.We show how temporally continuous observations are required to dissect end-point severity into functional resistance mechanisms.The results of our study show how QDR can be maintained by facilitating different defense mechanisms during host-parasite interaction and that the capacity of the QDR toolbox highly depends on the host's genetic context.We anticipate that the present findings display a valuable resource for more targeted functional characterization of the processes involved in QDR.Moreover,we show how modest phenotyping technology can be leveraged to help answer highly relevant biological questions. 展开更多
关键词 disease resistance qdr qdr high resolution phenotyping defense mechanisms quantitative disease resistance tomato crop wild relatives Sclerotinia sclerotiorum phenotyping technology lesion growth dynamics
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