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Defensive antibacterial coating in orthopaedic surgery: Current evidence and future direction
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作者 Richard Henry Randall Roberts Charles Gamble Ibrahim Malek 《World Journal of Orthopedics》 2025年第7期29-36,共8页
Periprosthetic joint infections contribute significantly to patient morbidity,prolonged hospital stays,and escalating healthcare costs.Defensive antibacterial coating(DAC®)hydrogel has emerged as a promising stra... Periprosthetic joint infections contribute significantly to patient morbidity,prolonged hospital stays,and escalating healthcare costs.Defensive antibacterial coating(DAC®)hydrogel has emerged as a promising strategy to combat these infections.It forms a biodegradable barrier that reduces bacterial adhesion and can deliver local antibiotics,thereby addressing a key mechanism in biofilm formation.Early clinical evidence suggests that DAC®effectively lowers infection recurrence in revision hip and knee arthroplasties,with additional benefits in trauma procedures and soft tissue repairs.Moreover,it has demonstrated compat-ibility with existing implants and surgical techniques,while potentially reducing overall antibiotic use and hospital stays.Despite these encouraging findings,data for its use in primary arthroplasty remains limited,underscoring the need for large-scale,high-quality studies.Future research is poised to refine DAC®’s antimicrobial efficacy through novel antibiotic combinations,personalised delivery systems,and broader applications beyond lower limb procedures.As the prevalence of comorbidities continues to rise,DAC®represents a valuable addi-tion to multifaceted infection control protocols,potentially transforming ortho-paedic care by enhancing patient outcomes and mitigating the economic and clinical burden of implant-related infections. 展开更多
关键词 Hospital-acquired infections Surgical site infections Periprosthetic joint infections Implant-related infections Orthopaedic surgery Antibiotic prophylaxis defensive antibacterial coating Biofilm prevention Revision arthroplasty Patient outcomes
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A Non-canonical Excitatory PV RGC–PV SC Visual Pathway for Mediating the Looming-evoked Innate Defensive Response 被引量:1
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作者 Man Yuan Sen Jin +4 位作者 Gao Tan Siyuan Song Yizong Liu Huadong Wang Yin Shen 《Neuroscience Bulletin》 SCIE CAS CSCD 2024年第3期310-324,共15页
Parvalbumin-positive retinal ganglion cells(PV+RGCs)are an essential subset of RGCs found in various species.However,their role in transmitting visual information remains unclear.Here,we characterized PV+RGCs in the r... Parvalbumin-positive retinal ganglion cells(PV+RGCs)are an essential subset of RGCs found in various species.However,their role in transmitting visual information remains unclear.Here,we characterized PV+RGCs in the retina and explored the functions of the PV+RGC-mediated visual pathway.By applying multiple viral tracing strategies,we investigated the downstream of PV+RGCs across the whole brain.Interestingly,we found that the PV+RGCs provided direct monosynaptic input to PV+excitatory neurons in the superficial layers of the superior colliculus(SC).Ablation or suppression of SC-projecting PV+RGCs abolished or severely impaired the flight response to looming visual stimuli in mice without affecting visual acuity.Furthermore,using transcriptome expression profiling of individual cells and immunofluorescence colocalization for RGCs,we found that PV+RGCs are predominant glutamatergic neurons.Thus,our findings indicate the critical role of PV+RGCs in an innate defensive response and suggest a non-canonical subcortical visual pathway from excitatory PV+RGCs to PV+SC neurons that regulates looming visual stimuli.These results provide a potential target for intervening and treating diseases related to this circuit,such as schizophrenia and autism. 展开更多
关键词 Parvalbumin-positive retinal ganglion cell Innate fear Superior colliculus Excitatory-excitatory neuronal connection Looming-evoked defensive response Subcortical pathway
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Analysis of Meteorological Conditions of Freeze Damage to Citrus in Southern Shaanxi in the Winter of 2010 and Defensive Countermeasures 被引量:4
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作者 柏秦凤 王景红 +3 位作者 霍治国 梁轶 张维敏 郭民主 《Agricultural Science & Technology》 CAS 2013年第3期444-449,共6页
In order to take advantage of the climate resources more effectively ac- cording to the local circumstances and to plan and develop the citrus industry in Southern Shaanxi more reasonably. On the basis of the investig... In order to take advantage of the climate resources more effectively ac- cording to the local circumstances and to plan and develop the citrus industry in Southern Shaanxi more reasonably. On the basis of the investigation of freeze dam- age to citrus occurring in Southern Shaanxi in the winter of 2010, the climatic back- ground for the formation of this freeze damage was analyzed. In combination with the freeze damage indicators during the overwintering period and the harmful accu- mulated cold during the cold wave, indexes for grading the freeze damage in southern Shaanxi were analyzed and verified, and the perspective of grading the freeze damage using the harmful accumulated cold during the cold wave was also presented. Through analyzing the extremely lowest temperature and the harmful ac- cumulated cold in the winter of 2010 and in history at 12 citrus growing counties (districts) in Ankang area and Hanzhong area, the reasons why the freeze damage to citrus during the overwintering period was severer in the west than in the east of Southern Shaanxi were discussed, and the results obtained were basically consistent with the actual situation observed from investigation. Finally, defensive countermea- sures against the freeze damage to citrus during the overwintering period were put forward from several aspects. 展开更多
关键词 CITRUS Southern Shaanxi Freeze damage during the overwintering peri- od Meteorological conditions defensive countermeasures
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Effects of Spores and Crude Toxins of Helminthosporium gramineum Rabenh f.sp.echinochloae on the Activity of Defensive Enzymes in Barnyardgrass 被引量:1
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作者 耿锐梅 余柳青 +3 位作者 罗成刚 李彦东 曹长代 《Agricultural Science & Technology》 CAS 2012年第12期2589-2593,共5页
[Objective] This study aimed to explore the effects of spores and crude toxins of Helminthosporium gramineum Rabenh f. sp. echinochloae(HGE) on the ac- tivity of defensive enzymes of barnyardgrass [Echinochloa crus-... [Objective] This study aimed to explore the effects of spores and crude toxins of Helminthosporium gramineum Rabenh f. sp. echinochloae(HGE) on the ac- tivity of defensive enzymes of barnyardgrass [Echinochloa crus-galli (L.) Beauv.]. [Method] The effects of spores and crude toxins of HGE, as well as the mixture of spores and crude toxins on the activity of defensive enzymes in barnyardgrass were determined under laboratory conditions. [Result] Spores and crude toxins of HGE had varying degrees of effects on PAL and POD activity, and no obvious effect on SOD activity in barnyardgrass. In addition, spores and toxins had some similar im- pacts on the defensive enzymes in barnyardgrass. [Conclusion] Since toxins have similar effects on the hosts as spores of fungal pathogen do, they can be a substi- tute for the fungal pathogen in studying the partial pathogenic mechanism of this pathogen due to its complexity in pathogenic process. 展开更多
关键词 Helminthosporium gramineum Rabenh f. sp. echinochloae (HGE) barn- yardgrass[Echinochloa crus-galli(L.) Beauv.] defensive enzymes Activity
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Defensive medicine practices among gastroenterologists in Japan 被引量:9
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作者 Toru Hiyama Masaharu Yoshihara +4 位作者 Shinji Tanaka Yuji Urabe Yoshihiko Ikegami Tatsuma Fukuhara Kazuaki Chayama 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第47期7671-7675,共5页
AIM: To clarify the prevalence of defensive medicine and the specific defensive medicine practices among gastroenterologists in Japan. METHODS: A survey of gastroenterologists in Hiroshima, Japan, was conducted by m... AIM: To clarify the prevalence of defensive medicine and the specific defensive medicine practices among gastroenterologists in Japan. METHODS: A survey of gastroenterologists in Hiroshima, Japan, was conducted by mail in March 2006. The number of gastroenterologists reporting defensive medicine behaviors or changes in their scope of practice and the reported defensive medicine practices, i.e., assurance and avoidance behaviors, were examined. RESULTS: A total of 131 (77%) out of 171 gastroenterologists completed the survey. Three (2%) respondents were sued, and most respondents (96%) had liability insurance. Nearly all respondents (98%) reported practicing defensive medicine. Avoidance behaviors, such as avoiding certain procedures or interventions and avoiding caring for high-risk patients, were very common (96%). Seventy-five percent of respondents reported often avoiding certain procedures or interventions. However, seasoned gastroenterologists (those in practice for more than 20 years) adopted avoidance behaviors significantly less often than those in practice for less than 10 years. Assurance behaviors, i.e., supplying additional services of marginal or no medical value, were also widespread (91%). Sixty-eight percent of respondents reported that they sometimes or often referred patients to other specialists unnecessarily. CONCLUSION: Defensive medicine may be highly prevalent among gastroenterologists throughout 3apan, with potentially serious implications regarding costs, access, and both technical and interpersonal quality of care. 展开更多
关键词 defensive medicine GASTROENTEROLOGIST JAPAN SURVEY Clinical practice
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Resistance genes mediate differential resistance to pine defensive substances α-Pinene and H_(2)O_(2) in Bursaphelenchus xylophilus with different levels of virulence 被引量:3
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作者 Lin Rui Hongbin Liu +1 位作者 Rui Liang Xiaoqin Wu 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第4期1753-1762,共10页
The pine wood nematode(PWN),Bursaphelenchus xylophilus(Steiner & Buhrer) Nickle,is the pathogen of pine wilt disease(PWD) which can devastate forests.PWN can be of hi gh or low severity and the mechanisms underlyi... The pine wood nematode(PWN),Bursaphelenchus xylophilus(Steiner & Buhrer) Nickle,is the pathogen of pine wilt disease(PWD) which can devastate forests.PWN can be of hi gh or low severity and the mechanisms underlying the differences in virulence are unclear.Therefore,it is necessary to study the relationship between differentiation of PWN severity and its resistance to the main defensive substances of pine species(i.e.,α-pinene and H_(2)O_(2)).The feeding rate and fecundity of PWN was examined at different levels of virulence under conditions of a-pinene and H_(2)O_(2) stress.Moreover,the expression patterns of the main resistance genes of PWN with different virulence were determined under conditions of α-pinene and H_(2)O_(2) stress.The feeding rate and fecundity of the high virulence strain AMA3 were higher than those of the low virulence strain YW4.The expression levels of the autophagy gene BxATG5,cytochrome P450 gene BxCYP33 D3,and glutathione S-transferase genes BxGST1 and BxGST3 in AMA3 increased significantly upon exposure to α-pinene for 2 h,while these genes showed smaller degrees of upregulation in YW4.Under conditions of H_(2)O_(2) stress,the expression levels of BxATG5,catalase genes Bxy-ctl-1 and Bxy-ctl-2,and the 2-cysteine peroxiredoxin gene BxPrx in AMA3 were higher than those in YW4.These findings suggest that high virulence PWN has greater resistance to pine defensive substances α-pinene and H_(2)O_(2) than low virulence PWN,and resistance genes mediate the differential resistance of PWN strains.This study will contribute to the clarification of the mechanism underlying virulence differentiation of PWN and will advance understanding of the pathogenic mechanism of PWD. 展开更多
关键词 Pine wood nematode VIRULENCE defensive substances Autophagy gene Detoxification gene Antioxidant gene
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Somatostatin-Positive Neurons in the Rostral Zona Incerta Modulate Innate Fear-Induced Defensive Response in Mice 被引量:3
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作者 Shan Lin Meng-Yue Zhu +7 位作者 Meng-Yu Tang Mi Wang Xiao-Dan Yu Yi Zhu Shi-Ze Xie Dan Yang Jiadong Chen Xiao-Ming Li 《Neuroscience Bulletin》 SCIE CAS CSCD 2023年第2期245-260,共16页
Defensive behaviors induced by innate fear or Pavlovian fear conditioning are crucial for animals to avoid threats and ensure survival.The zona incerta(ZI)has been demonstrated to play important roles in fear learning... Defensive behaviors induced by innate fear or Pavlovian fear conditioning are crucial for animals to avoid threats and ensure survival.The zona incerta(ZI)has been demonstrated to play important roles in fear learning and fear memory,as well as modulating auditory-induced innate defensive behavior.However,whether the neuronal subtypes in the ZI and specific circuits can mediate the innate fear response is largely unknown.Here,we found that somatostatin(SST)-positive neurons in the rostral ZI of mice were activated by a visual innate fear stimulus.Optogenetic inhibition of SST-positive neurons in the rostral ZI resulted in reduced flight responses to an overhead looming stimulus.Optogenetic activation of SST-positive neurons in the rostral ZI induced fear-like defensive behavior including increased immobility and bradycardia.In addition,we demonstrated that manipulation of the GABAergic projections from SST-positive neurons in the rostral ZI to the downstream nucleus reuniens(Re)mediated fear-like defensive behavior.Retrograde trans-synaptic tracing also revealed looming stimulus-activated neurons in the superior colliculus(SC)that projected to the Re-projecting SST-positive neurons in the rostral ZI(SC-ZIrSST-Re pathway).Together,our study elucidates the function of SST-positive neurons in the rostral ZI and the SC-ZIrSST-Re tri-synaptic circuit in mediating the innate fear response. 展开更多
关键词 Innate fear Zona incerta Somatostatinpositive neurons Looming stimulus defensive behavior
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More than mimicry? Evaluating scope for flicker-fusion as a defensive strategy in coral snake mimics 被引量:1
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作者 Georgia C. TITCOMB David W. KIKUCHI David W. PFENNIG 《Current Zoology》 SCIE CAS CSCD 2014年第1期123-130,共8页
Coral snakes and their mimics often have brightly colored banded patterns, generally associated with warning colora- tion or mimicry. However, such color patterns have also been hypothesized to aid snakes in escaping ... Coral snakes and their mimics often have brightly colored banded patterns, generally associated with warning colora- tion or mimicry. However, such color patterns have also been hypothesized to aid snakes in escaping predators through a "flicker-fusion" effect. According to this hypothesis, banded color patterns confuse potential predators when a snake transitions from resting to moving because its bands blur together to form a different color. To produce this motion blur, a moving snake's bands must transition faster than the critical flicker-fusion rate at which a predator's photoreceptors can refresh. It is unknown if coral snakes or their mimics meet this requirement. We tested this hypothesis by measuring the movement speed and color pat- terns of two coral snake mimics, Lampropeltis triangulum campbelli and L. elapsoides, and comparing the frequency of color transitions to the photoreceptor activity of the avian eye. We found that snakes often produced a motion blur, but moving snakes created a blurring effect more often in darker conditions, such as sunrise, sunset, and nighttime when these snakes are often active. Thus, at least two species of coral snake mimics are capable of achieving flicker-fusion, indicating that their color patterns may confer an additional defense aside from mimicry 展开更多
关键词 Coral snake mimicry Flicker-fusion effect CFF Kingsnake defensive strategy
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Defensive medicine:It is time to finally slow down an epidemic 被引量:1
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作者 Sandro Vento Francesca Cainelli Alfredo Vallone 《World Journal of Clinical Cases》 SCIE 2018年第11期406-409,共4页
Defensive medicine is widespread and practiced the world over, with serious consequences for patients, doctors, and healthcare costs. Even students and resi-dents are exposed to defensive medicine practices and taught... Defensive medicine is widespread and practiced the world over, with serious consequences for patients, doctors, and healthcare costs. Even students and resi-dents are exposed to defensive medicine practices and taught to take malpractice liability into consideration when making clinical decisions. Defensive medicine is generally thought to stem from physicians' perception that they can easily be sued by patients or their relatives who seek compensation for presumed medical errors. However, in our view the growth of defensive medicine should be seen in the context of larger changes in the conception of medicine that have taken place in the last few decades, undermining the patient–physician trust, which has traditionally been the main source of professional satisfaction for physicians. These changes include the following: time directly spent with patients has been overtaken by time devoted to electronic health records and desk work; family doctors have played a progressively less central role; clinical reasoning is being replaced by guidelines and algorithms; the public at large and a number of young physicians tend to believe that medicine is a perfect science rather than an imperfect art, as it continues to be; and modern societies do not tolerate the inevitable morbidity and mortality. To finally reduce the increasing defensive behavior of doctors around the world, the decriminalization of medical errors and the assurance that they can be dealt with in civil courts or by medical organizations in all countries could help but it would not suffice. Physicians and surgeons should be allowed to spend the time they need with their patients and should give clinical reasoning the importance it deserves. The institutions should support the doctors who have experienced adverse patient events, and the media should stop reporting with excessive evidence presumed medical errors and subject physicians to "public trials" before they are eventually judged in court. 展开更多
关键词 ADVERSE event Clinical reasoning defensive medicine DOCTOR-PATIENT relationship Healthcare cost MEDICAL education MEDICAL error
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Localization of a defensive volatile 4-hydroxy-4-methylpentan-2-one in the capitate glandular trichomes of Oenothera glazioviana 被引量:1
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作者 Yanyun Tan Desen Li +3 位作者 Juan Hua Shihong Luo Yan Liu Shenghong Li 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第3期154-159,共6页
Glandular trichomes of plants produce a wide variety of secondary metabolites which are considered as major defensive chemicals. The capitate glandular trichomes of Oenothera glazioviana(Onagraceae) were collected wit... Glandular trichomes of plants produce a wide variety of secondary metabolites which are considered as major defensive chemicals. The capitate glandular trichomes of Oenothera glazioviana(Onagraceae) were collected with laser microdissection and analyzed by gas chromatography-mass spectrometry. The volatile compound 4-hydroxy-4-methylpentan-2-one(1) was identified. We found that compound 1 displays antimicrobial, insecticidal, and phytotoxic activities. These results suggest that compound 1 might function as a defensive compound in the capitate glandular trichomes of O. glazioviana against pathogens, insect herbivores, and presumably competitive plants as well. 展开更多
关键词 Oenothera glazioviana Capitate glandular trichomes Laser microdissection 4-Hydroxy-4-methylpentan-2-one defensive functions
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Analysis of a Lightning Strike Accident of a Rural House and Defensive Measures 被引量:1
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作者 Bin WU Xiangping ZHOU 《Meteorological and Environmental Research》 CAS 2020年第3期48-50,共3页
A lightning strike accident of a residential house in the rural areas of Neijiang is analyzed through on-site investigation,and the causes are discussed. Defensive measures of lightning disasters are proposed to provi... A lightning strike accident of a residential house in the rural areas of Neijiang is analyzed through on-site investigation,and the causes are discussed. Defensive measures of lightning disasters are proposed to provide reference for the prevention of lightning disasters in the construction of new countryside. 展开更多
关键词 Lightning strike accident Cause analysis defensive measures
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Cross-Site Scripting Attacks and Defensive Techniques: A Comprehensive Survey* 被引量:1
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作者 Sonkarlay J. Y. Weamie 《International Journal of Communications, Network and System Sciences》 2022年第8期126-148,共23页
The advancement of technology and the digitization of organizational functions and services have propelled the world into a new era of computing capability and sophistication. The proliferation and usability of such c... The advancement of technology and the digitization of organizational functions and services have propelled the world into a new era of computing capability and sophistication. The proliferation and usability of such complex technological services raise several security concerns. One of the most critical concerns is cross-site scripting (XSS) attacks. This paper has concentrated on revealing and comprehensively analyzing XSS injection attacks, detection, and prevention concisely and accurately. I have done a thorough study and reviewed several research papers and publications with a specific focus on the researchers’ defensive techniques for preventing XSS attacks and subdivided them into five categories: machine learning techniques, server-side techniques, client-side techniques, proxy-based techniques, and combined approaches. The majority of existing cutting-edge XSS defensive approaches carefully analyzed in this paper offer protection against the traditional XSS attacks, such as stored and reflected XSS. There is currently no reliable solution to provide adequate protection against the newly discovered XSS attack known as DOM-based and mutation-based XSS attacks. After reading all of the proposed models and identifying their drawbacks, I recommend a combination of static, dynamic, and code auditing in conjunction with secure coding and continuous user awareness campaigns about XSS emerging attacks. 展开更多
关键词 XSS Attacks defensive Techniques VULNERABILITIES Web Application Security
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Formation of the Looming-evoked Innate Defensive Response during Postnatal Development in Mice
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作者 Shanping Chen Huiying Tan +3 位作者 Zhijie Wang Yu-ting Tseng Xiaotao Li Liping Wang 《Neuroscience Bulletin》 SCIE CAS CSCD 2022年第7期741-752,共12页
Environmental threats often trigger innate defensive responses in mammals.However,the gradual development of functional properties of these responses during the postnatal development stage remains unclear.Here,we repo... Environmental threats often trigger innate defensive responses in mammals.However,the gradual development of functional properties of these responses during the postnatal development stage remains unclear.Here,we report that looming stimulation in mice evoked fight behavior commencing at P14-16 and had fully developed by P20-24.The visual-evoked innate defensive response was not significantly altered by sensory deprivation at an early postnatal stage.Furthermore,the percentages of wide-field and horizontal cells in the superior colliculus were notably elevated at P20-24.Our findings define a developmental time window for the formation of the visual innate defense response during the early postnatal period and_provide important insight into the underlying mechanism. 展开更多
关键词 Innate defensive response Postnatal stage Superiorcolliculus
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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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Model Predictive Control Based Defensive Guidance Law in Three-Body Engagement
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作者 Jinglei Ren Zhenya Wang Feng Fang 《Journal of Beijing Institute of Technology》 EI CAS 2022年第6期559-569,共11页
Model predictive control(MPC)has been widely used in process industry,but its appli-cations to missile guidance law are relatively rare.In this paper,MPC is introduced to design defen-sive guidance law in a three-body... Model predictive control(MPC)has been widely used in process industry,but its appli-cations to missile guidance law are relatively rare.In this paper,MPC is introduced to design defen-sive guidance law in a three-body engagement,where a defending missile(i.e.,defender)is employed to protect a target aircraft from an attacking missile.Based on nonlinear kinematic equa-tions,an explicit linear discrete-time model is derived as the predictive model.Then the defensive guidance problem is formulated as a quadratic programming problem,and a fast algorithm for the MPC guidance law is developed.The advantages of the MPC guidance law include the applicabil-ity to scenarios with unknown guidance strategy of attacking missile,nonlinear kinematics and mul-tiple constraints.Another key feature is that the proposed approach does not require alteration in the target maneuver.Simulation results show that the MPC guidance law works well and can meet real-time requirements. 展开更多
关键词 defensive guidance law model predictive control three-body engagement
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Systemic Activation of Defensive Enzymes and Protection in Tobacco Plantlets against <i>Phytophthora nicotianae</i>Induced by Oligosaccharins
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作者 Alejandro Bernardo Falcón-Rodríguez Daimy Costales +2 位作者 Juan Carlos Cabrera Ruddy Wattiez Miguel ángel Martínez-Téllez 《American Journal of Plant Sciences》 2014年第21期3354-3363,共10页
Oligosaccharins are potent biomolecules which activate defense responses and resistance in tobacco plants. However, it is not known the systemic behavior of defensive enzymes activated by these elicitors. In this work... Oligosaccharins are potent biomolecules which activate defense responses and resistance in tobacco plants. However, it is not known the systemic behavior of defensive enzymes activated by these elicitors. In this work, the dynamic behavior of key defensive enzymes was evaluated in tobacco plant leaves previously treated through the roots with chitosan polymer (CH), chitosan (COS) and pectic (OGAS) oligosaccharides and Spermine (Sp). All macromolecules tested activated protein levels and defense enzymatic activity in tobacco leaves but with different response dynamics among them and depending on the biochemical variable evaluated. Defense response above control levels were detected since 12 hours after treatments and it consisted in a biphasic behavior with two peaks for PAL (EC 4.3.1.5) and β 1 - 3 glucanase (EC 3.2.1.6) enzymatic activities. The highest enzymatic levels for these enzymes were achieved at 48 hours in plantlets elicited with COS and at 72 hours for those plants treated with chitosan polymer, while the highest POD (EC 1.11.1.6) activity was detected with CH between 48 and 72 hours. These results demonstrated systemic defense activation by oligosaccharins in tobacco whose dynamic of defense response is affected by the kind of oligosaccharins tested. When applying OGAS by foliar spray on tobacco, systemic resistance against Phytoththora nicotianae was induced and plantlets were protected with the low concentration tested by 46% under the bioassays conditions performed. Moreover, enzymatic determinations on roots and leaves previous to plant-pathogen interaction showed increments above 30% of control levels for PAL and POD activities. It means that oligosaccharins activate local and systemic defense responses in plants in the absent of pathogen infection. 展开更多
关键词 SYSTEMIC INDUCED Resistance Oligosaccharins TOBACCO defensive Enzymes
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Defensive Village Houses in South China
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作者 GUO ZHIDONG 《China Today》 2019年第6期78-80,共3页
Kaiping Diaolou is a special and unique architectural style of Chinese countryside dwellings. It is famous for the rare and complex fusion of Chinese and Western architectural styles. The Diaolou is also an important ... Kaiping Diaolou is a special and unique architectural style of Chinese countryside dwellings. It is famous for the rare and complex fusion of Chinese and Western architectural styles. The Diaolou is also an important historic and cultural site as it shows China’s embrace of foreign culture in a transitional period. On June 28, 2007, Kaiping Diaolou was inscribed into the world cultural heritage list. 展开更多
关键词 defensive VILLAGE Houses SOUTH China
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AB010.A retinoraphe projection regulates looming-induced defensive behavior
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作者 Chaoran Ren 《Annals of Eye Science》 2017年第1期364-364,共1页
Animals promote their survival by avoiding rapidly approaching objects that indicate threats.It is believed that looming cues are detected by retinal ganglion cells(RGCs)that project to the superior colliculus(SC).How... Animals promote their survival by avoiding rapidly approaching objects that indicate threats.It is believed that looming cues are detected by retinal ganglion cells(RGCs)that project to the superior colliculus(SC).However,the exact type of RGC that transmits looming-related signals remains unclear.Here we identify a specific transient type of RGCs that controls mouse looming-evoked defensive response by sending axonal collaterals to the dorsal raphe nucleus(DRN)and SC.Looming signals transmitted by DRN-projecting RGCs activate DRN GABA neurons and in turn inhibit serotonin neurons.Moreover,optogenetically stimulating serotonin neurons reduces looming-evoked defensive behaviors.Thus,a dedicated population of RGCs detects rapidly approaching visual threats and their input to the DRN controls a serotonergic self-gating mechanism that regulates innate defensive responses.Our study provides new insights into how DRN and SC work in concert to extract and translate visual threats into defensive behavioral responses. 展开更多
关键词 defensive responses dorsal raphe retinal ganglion cells(RGCs)
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Defensive Responses of Rice Genotypes for Resistance Against Rice Leaffolder Cnaphalocrocis medinalis 被引量:2
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作者 M. PUNITHAVALLI N. M. MUTHUKRISHNAN M. BALAJI RAJKUMA 《Rice science》 SCIE 2013年第5期363-370,共8页
The experiment was carried out to assess the reaction of different categories of rice genotypes viz., resistant, susceptible, hybrid, scented, popular and wild in response to the infestation by rice leaffolder (RLF)... The experiment was carried out to assess the reaction of different categories of rice genotypes viz., resistant, susceptible, hybrid, scented, popular and wild in response to the infestation by rice leaffolder (RLF), Cnaphalocrocis medinalis (Guenee) and to explore the possible use of these genotypes in developing RLF-resistant rice varieties. The changes of various biochemical constituents such as leaf soluble protein, phenol, ortho-dihydroxy phenol, tannin and enzymes viz., peroxidase, phenyl alanine ammonia lyase (PAL) were assessed spectrophotometrically in all the rice genotypes before and after RLF infestation. The protein profile was analyzed using sodium dodecyl sulphate-poly acrylamide gel electrophoresis (SDS-PAGE) method. A significant constituent of biochemical content such as tannin, phenol and ortho-dihydroxy phenol has been increased along with enzyme activities of peroxidase and PAL in the infested resistant (Ptb 33, TKM6 and LFR831311) and wild rice genotypes (Oryza minuta and O. rhizomatis). A decrease in leaf protein content was evident invariably in all the infested rice genotypes. It is also evident that the contents of biochemicals such as phenol, ortho- dihydroxy phenol and tannin were negatively correlated with leaffolder damage. However, leaf protein content was positively correlated with the damage by rice leaffolder. SDS-PAGE analysis for total protein profiling of healthy and C. medinalis-infested genotypes revealed the enhanced expression of a high molecular weight (〉 97 kDa) protein in all the genotypes. Besides, there was also an increased induction of a 38 kDa protein in C. medinalis infested resistant genotypes, which was absent in uninfested plants. The present investigation proved that the elevated levels of biochemicals and enzymes may play a vital role in rice plants resistance to RLF. 展开更多
关键词 rice genotype BIOCHEMICAL defense enzyme rice leaffolder RESISTANCE
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