Heat stress hinders the growth and productivity of sweetpotato plants,predominantly through oxidative damage to cellular membranes.Therefore,the development of efficient approaches for mitigating heat-related impairme...Heat stress hinders the growth and productivity of sweetpotato plants,predominantly through oxidative damage to cellular membranes.Therefore,the development of efficient approaches for mitigating heat-related impairments is essential for the long-term production of sweetpotatoes.Melatonin has been recognised for its capacity to assist plants in dealing with abiotic stress conditions.This research aimed to investigate how different doses of exogenous melatonin influence heat damage in sweetpotato plants.Heat stress drastically affected shoot and root fresh weight by 31.8 and 44.5%,respectively.This reduction resulted in oxidative stress characterised by increased formation of hydrogen peroxide(H_(2)O_(2))by 804.4%,superoxide ion(O_(2)^(·-))by 211.5%and malondialdehyde(MDA)by 234.2%.Heat stress also reduced chlorophyll concentration,photosystemⅡefficiency(F_v/F_m)by 15.3%and gaseous exchange.However,pre-treatment with 100μmol L^(-1)melatonin increased growth and reduced oxidative damage to sweetpotato plants under heat stress.In particular,melatonin decreased H_(2)O_(2),O_(2)^(·-)and MDA by 64.8%,42.7%and 38.2%,respectively.Melatonin also mitigated the decline in chlorophyll levels and improved stomatal traits,gaseous exchange and F_(v)/F_(m)(13%).Results suggested that the favorable outcomes of melatonin treatment can be associated with elevated antioxidant enzyme activity and an increase in non-enzymatic antioxidants and osmo-protectants.Overall,these findings indicate that exogenous melatonin can improve heat stress tolerance in sweetpotatoes.This stu dy will assist re searchers in further investigating how melatonin makes sweetpotatoes more resistant to heat stress.展开更多
In order to solve the problem that the ripple-effect analy- sis for the operational architecture of air defense systems (OAADS) is hardly described in quantity with previous modeling approaches, a supernetwork model...In order to solve the problem that the ripple-effect analy- sis for the operational architecture of air defense systems (OAADS) is hardly described in quantity with previous modeling approaches, a supernetwork modeling approach for the OAADS is put for- ward by extending granular computing. Based on that operational units and links are equal to different information granularities, the supernetwork framework of the OAADS is constructed as a “four- network within two-layer” structure by forming dynamic operating coalitions, and measuring indexes of the ripple-effect analysis for the OAADS are given combining with Laplace spectral radius. In this framework, via analyzing multidimensional attributes which inherit relations between operational units in different granular scales, an extended granular computing is put forward integrating with a topological structure. Then the operation process within the supernetwork framework, including transformation relations be- tween two layers in the vertical view and mapping relations among functional networks in the horizontal view, is studied in quantity. As the application case shows, comparing with previous modeling approaches, the supernetwork model can validate and analyze the operation mechanism in the air defense architecture, and the ripple-effect analysis can be used to confirm the key operational unit with micro and macro viewpoints.展开更多
Under the indoor simulant conditions, toxic effects of crude-oil-contaminated soil which was put into aquatic environment on the young fishes Carassius auratus and their hepatic antioxidant system after a 20-d exposur...Under the indoor simulant conditions, toxic effects of crude-oil-contaminated soil which was put into aquatic environment on the young fishes Carassius auratus and their hepatic antioxidant system after a 20-d exposure were investigated. Results showed that the relationship between the mortality of C. auratus and the exposed doses could be divided into 3 phases: fishes exposed to the low dose groups (0.5-5.0 g/L) were dead due to the ingestion of crude-oil-contaminated soils in aquatic environment; at the medium dose groups (5.0-25.0 g/L) fishes were dead due to the penetration of toxic substances; at the high dose groups (25.0-50.0 g/L) fishes were dead due to environmental stress. The highest mortality and death speed were found in the 1.0 g/L dose group, and the death speed was sharply increased in the 50.0 g/L dose group in the late phase of exposure. The activities of superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) and the content of malaondialdehyde (MDA) in the hepatic tissues of C. auratus were induced significantly. The activity of SOD was increased and then decreased. It was significantly inhibited in the 50.0 g/L dose group. The activity of CAT was highly induced, and restored to a level which is little more than the control when the exposed doses exceeded 10.0 g/L. The activity of GST was the most sensitive, it was significantly induced in all dose groups, and the highest elevation was up to 6 times in the 0.5 g/L dose group comparing with the control. The MDA content was significantly elevated in the 50.0 g/L dose group, and the changes of the MDA content were opposite with the changes of GST activity.展开更多
The fire distribution can be divided into weapon assignment and firing time scheduling. The criterion of weapon allocation is that a target with greater threat has higher priority. And the criterion of firing time sch...The fire distribution can be divided into weapon assignment and firing time scheduling. The criterion of weapon allocation is that a target with greater threat has higher priority. And the criterion of firing time scheduling is that a target can be damaged with the expected probability before a specific time. A fire distribution scheme and a program for the integrated missile-gun air defense system based on a criterion of earlier damage were presented. An example was taken to illustrate its effectiveness.展开更多
Various application domains require the integration of distributed real-time or near-real-time systems with non-real-time systems.Smart cities,smart homes,ambient intelligent systems,or network-centric defense systems...Various application domains require the integration of distributed real-time or near-real-time systems with non-real-time systems.Smart cities,smart homes,ambient intelligent systems,or network-centric defense systems are among these application domains.Data Distribution Service(DDS)is a communication mechanism based on Data-Centric Publish-Subscribe(DCPS)model.It is used for distributed systems with real-time operational constraints.Java Message Service(JMS)is a messaging standard for enterprise systems using Service Oriented Architecture(SOA)for non-real-time operations.JMS allows Java programs to exchange messages in a loosely coupled fashion.JMS also supports sending and receiving messages using a messaging queue and a publish-subscribe interface.In this article,we propose an architecture enabling the automated integration of distributed real-time and non-real-time systems.We test our proposed architecture using a distributed Command,Control,Communications,Computers,and Intelligence(C4I)system.The system has DDS-based real-time Combat Management System components deployed to naval warships,and SOA-based non-real-time Command and Control components used at headquarters.The proposed solution enables the exchange of data between these two systems efficiently.We compare the proposed solution with a similar study.Our solution is superior in terms of automation support,ease of implementation,scalability,and performance.展开更多
Arsenic(As)contaminated food chains have emerged as a serious public concern for humans and animals and are known to affect the cultivation of edible crops throughout the world.Therefore,the present study was designed...Arsenic(As)contaminated food chains have emerged as a serious public concern for humans and animals and are known to affect the cultivation of edible crops throughout the world.Therefore,the present study was designed to investigate the individual as well as the combined effects of exogenous silicon(Si)and sodium nitroprusside(SNP),a nitric oxide(NO)donor,on plant growth,metabolites,and antioxidant defense systems of radish(Raphanus sativus L.)plants under three different concentrations of As stress,i.e.,0.3,0.5,and 0.7 mM in a pot experiment.The results showed that As stress reduced the growth parameters of radish plants by increasing the level of oxidative stress markers,i.e.,malondialdehyde and hydrogen peroxide.However,foliar application of Si(2 mM)and pretreatment with SNP(100μM)alone as well as in combination with Si improved the plant growth parameters,i.e.,root length,fresh and dry weight of plants under As stress.Furthermore,As stress also reduced protein,and metabolites contents(flavonoids,phenolic and anthocyanin).Activities of antioxidative enzymes such as catalase(CAT),ascorbate peroxidase(APX),guaiacol peroxidase(POD),and polyphenol oxidase(PPO),as well as the content of non-enzymatic antioxidants(glutathione and ascorbic acid)decreased under As stress.In most of the parameters in radish,As III concentration showed maximum reduction,as compared to As I and II concentrations.However,the individual and combined application of Si and NO significantly alleviated the As-mediated oxidative stress in radish plants by increasing the protein,and metabolites content.Enhancement in the activities of CAT,APX,POD and PPO enzymes were recorded.Contents of glutathione and ascorbic acid were also enhanced in response to co-application of Si and NO under As stress.Results obtained were more pronounced when Si and NO were applied in combination under As stress,as compared to their individual application.In short,the current study highlights that Si and NO synergistically regulate plant growth through lowering the As-mediated oxidative stress by upregulating the metabolites content,activity of antioxidative enzymes and non-enzymatic antioxidants in radish plants.展开更多
The concept of smart power requires to combine soft and hard power. Thus, smart power is a new approach for the US politics towards the Middle East. As a consequence of smart power politics of the US, some newly membe...The concept of smart power requires to combine soft and hard power. Thus, smart power is a new approach for the US politics towards the Middle East. As a consequence of smart power politics of the US, some newly members of the EU and Turkey has become a part of missile defense system. This is a significant indicator of usage of smart power for the EU members and Turkey. The security policies and practices of the US disclose a necessity for straight allies. For this reason, the relationship between the US, the EU and Turkey may be conceptualize with reference to the concept of smart power. In the case of Missile Defense System, Turkey has agreed to be a participant of this system after signing an agreement with the US. After that, Turkish government has confronted with some interior and exterior political difficulties. One of the most important difficulties is the interior resistance of missile defense system's Kiirecik Radar Station and its usage in Turkey. Another important point is the question of control of Turkish National Security and Defense strategy. In that respect, the US government's smart power applications may be included in the establishment of the radar station. The EU has also been included in that strategy. This paper will argue smart power practices of the US, the EU and Turkey with reference to comparative practices of power politics and the case of Missile Defense System. In this way, a comprehensive and system-type assessment of possible responses and the change in relations between stakeholder states not only in the issue of a set-up of a Turkish radar station, but on a broader range of international "hard" security balance will be demonstrated.展开更多
Marine zooplankton responds sensitively to elevated seawater CO_2 concentration. However, the underlying physiological mechanisms have not been studied well. We therefore investigated the effects of elevated CO_2conce...Marine zooplankton responds sensitively to elevated seawater CO_2 concentration. However, the underlying physiological mechanisms have not been studied well. We therefore investigated the effects of elevated CO_2concentration(0.08%, 0.20%, 0.50% and 1.00%) on antioxidant defense components, as well as two detoxification enzymes of Calanus sinicus(copepod). The results showed that glutathione peroxidase(GPx) activity exposed to CO_2-acidified seawater was significantly stimulated while other antioxidant components, including glutathione-Stransferase(GST) activity, superoxide dismutase(SOD) activity decreased significantly with reduced glutathione(GSH) level and GSH/oxidized glutathione(GSSG) value. CO_2-acidified seawater exhibited stimulatory effects on adenosine triphosphatase(ATPase) activity and acetylcholinesterase(Ach E) activity was inhibited. Moreover, the results of principal component analysis indicated that 75.93% of the overall variance was explained by the first two principal components. The elevated CO_2 concentration may affect the metabolism and survivals of copepods through impacts these enzymes activities. Further studies are needed to focus on the synergistic effects of elevated CO_2 concentration and other environmental factors on copepods.展开更多
In this paper,the security problem for the multi-access edge computing(MEC)network is researched,and an intelligent immunity-based security defense system is proposed to identify the unauthorized mobile users and to p...In this paper,the security problem for the multi-access edge computing(MEC)network is researched,and an intelligent immunity-based security defense system is proposed to identify the unauthorized mobile users and to protect the security of whole system.In the proposed security defense system,the security is protected by the intelligent immunity through three functions,identification function,learning function,and regulation function,respectively.Meanwhile,a three process-based intelligent algorithm is proposed for the intelligent immunity system.Numerical simulations are given to prove the effeteness of the proposed approach.展开更多
The response of enzyme and non-enzymatic antioxidants of Mn hyperaccumuator, Polygonum hydropiper (P. hydropiper), to Mn stress was studied using hydroponics culture experiments to explore the mechanism of Mn tolera...The response of enzyme and non-enzymatic antioxidants of Mn hyperaccumuator, Polygonum hydropiper (P. hydropiper), to Mn stress was studied using hydroponics culture experiments to explore the mechanism of Mn tolerance in this species. Results showed that both chlorophyll and carotenoid contents significantly (p〈0.05) decreased with increasing Mn treatment levels (0, 0.5, 1, 2, 4, and 8 mg/L) in hydroponics. The concentrations of malondialdehyde (MDA) and hydrogen peroxide (H202) in the root and shoot of P hydropiper were accumulated under Mn stress. Meanwhile, the anti-oxidative functions of several important enzymes, including superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and peroxidase (POD) in plants were stimulated by Mn spike in leaves and roots, especially at low Mn stress; while sulfhydryl group (--SH) and glutathion (GSH) were likely involved in Mn detoxification ofP. hydropiper under high Mn stress.展开更多
In order to cope with the increasing threat of the ballistic missile(BM)in a shorter reaction time,the shooting policy of the layered defense system needs to be optimized.The main decisionmaking problem of shooting op...In order to cope with the increasing threat of the ballistic missile(BM)in a shorter reaction time,the shooting policy of the layered defense system needs to be optimized.The main decisionmaking problem of shooting optimization is how to choose the next BM which needs to be shot according to the previous engagements and results,thus maximizing the expected return of BMs killed or minimizing the cost of BMs penetration.Motivated by this,this study aims to determine an optimal shooting policy for a two-layer missile defense(TLMD)system.This paper considers a scenario in which the TLMD system wishes to shoot at a collection of BMs one at a time,and to maximize the return obtained from BMs killed before the system demise.To provide a policy analysis tool,this paper develops a general model for shooting decision-making,the shooting engagements can be described as a discounted reward Markov decision process.The index shooting policy is a strategy that can effectively balance the shooting returns and the risk that the defense mission fails,and the goal is to maximize the return obtained from BMs killed before the system demise.The numerical results show that the index policy is better than a range of competitors,especially the mean returns and the mean killing BM number.展开更多
Salinity is one of the most severe abiotic stresses for crop production.The present study investigates the salinityinduced modulation in growth indicators,morphology and movement of stomata,photosynthetic pigments,act...Salinity is one of the most severe abiotic stresses for crop production.The present study investigates the salinityinduced modulation in growth indicators,morphology and movement of stomata,photosynthetic pigments,activity of carbonic anhydrase as well as nitrate reductase,and antioxidant systems in two varieties of chickpea(Pusa-BG5023,and Pusa-BGD72).On 20^(th) day of sowing,plants were treated with varying levels of NaCl(0,50,100,150 and 200 mM)followed by sampling on 45 days of sowing.Recorded observations on both the varieties reveal that salt stress leads to a significant decline in growth,dry biomass,leaf area,photosynthetic pigments,protein content,stomatal behavior,cell viability,activity of nitrate reductase and carbonic anhydrase with the rise in the concentration of salt.However,quantitatively these changes were less in Pusa-BG5023 as compared to Pusa-BGD72.Furthermore,salinity-induced oxidative stress enhanced malondialdehyde content,superoxide radicals,foliar proline content,and the enzymatic activities of superoxide dismutase,catalase,and peroxidase.The variety Pusa-BGD72 was found more sensitive than Pusa-BG5023 to salt stress.Out of different graded concentrations(50,100,150 and 200 mM)of sodium chloride,50 mM was least toxic,and 200 mM was most damaging.The differential behavior of these two varieties measured in terms of stomatal behavior,cell viability,photosynthetic pigments,and antioxidant defense system can be used as prospective indicators for selection of chickpea plants for salt tolerance and sensitivity.展开更多
As a large amount of data needs to be processed and speed needs to be improved,edge computing with ultra-low latency and ultra-connectivity is emerging as a new paradigm.These changes can lead to new cyber risks,and s...As a large amount of data needs to be processed and speed needs to be improved,edge computing with ultra-low latency and ultra-connectivity is emerging as a new paradigm.These changes can lead to new cyber risks,and should therefore be considered for a security threat model.To this end,we constructed an edge system to study security in two directions,hardware and software.First,on the hardware side,we want to autonomically defend against hardware attacks such as side channel attacks by configuring field programmable gate array(FPGA)which is suitable for edge computing and identifying communication status to control the communication method according to priority.In addition,on the software side,data collected on the server performs end-to-end encryption via symmetric encryption keys.Also,we modeled autonomous defense systems on the server by using machine learning which targets to incoming and outgoing logs.Server log utilizes existing intrusion detection datasets that should be used in real-world environments.Server log was used to detect intrusion early by modeling an intrusion prevention system to identify behaviors that violate security policy,and to utilize the existing intrusion detection data set that should be used in a real environment.Through this,we designed an efficient autonomous defense system that can provide a stable system by detecting abnormal signals from the device and converting them to an effective method to control edge computing,and to detect and control abnormal intrusions on the server side.展开更多
: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
Marine ecosystems are facing escalating environmental fluctuations owing to climate change and human activities,imposing pressures on marine species.To withstand recurring environmental challenges,marine organisms,esp...Marine ecosystems are facing escalating environmental fluctuations owing to climate change and human activities,imposing pressures on marine species.To withstand recurring environmental challenges,marine organisms,especially benthic species lacking behavioral choices to select optimal habitats,have to utilize well-established strategies such as the antioxidant defense system(ADS)to ensure their survival.Therefore,understanding of the mechanisms governing the ADS-based response is essential for gaining insights into adaptive strategies for managing environmental challenges.Here we conducted a com-parative analysis of the physiological and transcriptional responses based on the ADS during two rounds of'hypersalinity-recovery'challenges in two model congeneric invasive ascidians,Ciona robusta and C.savignyi.Our results demonstrated that C.savignyi exhibited higher tolerance and resistance to salinity stresses at the physiological level,while C.robusta demonstrated heightened responses at the transcriptional level.We observed distinct transcriptional responses,particularly in the utilization of two superoxide dismutase(SOD)isoforms.Both Ciona species developed physiological stress memory with elevated total SOD(T-SOD)and glutathione(GSH)responses,while only C.robusta demonstrated transcriptional stress memory.The regulatory distinctions within the Nrf2-Keap1 signalling pathway likely explain the formation disparity of transcriptional stress memory between both Ciona species.These findings support the'context-dependent stress memory hypothesis',emphasizing the emergence of species-specific stress memory at diverse regulatory levels in response to recurrent environmental challenges.Our results enhance our understanding of the mechanisms of environmental challenge manage-ment in marine species,particularly those related to the ADS.展开更多
The development of Intelligent Railway Transportation Systems necessitates incorporating privacy-preserving mechanisms into AI models to protect sensitive information and enhance system efficiency.Federated learning o...The development of Intelligent Railway Transportation Systems necessitates incorporating privacy-preserving mechanisms into AI models to protect sensitive information and enhance system efficiency.Federated learning offers a promising solution by allowing multiple clients to train models collaboratively without sharing private data.However,despite its privacy benefits,federated learning systems are vulnerable to poisoning attacks,where adversaries alter local model parameters on compromised clients and send malicious updates to the server,potentially compromising the global model’s accuracy.In this study,we introduce PMM(Perturbation coefficient Multiplied by Maximum value),a new poisoning attack method that perturbs model updates layer by layer,demonstrating the threat of poisoning attacks faced by federated learning.Extensive experiments across three distinct datasets have demonstrated PMM’s ability to significantly reduce the global model’s accuracy.Additionally,we propose an effective defense method,namely CLBL(Cluster Layer By Layer).Experiment results on three datasets have confirmed CLBL’s effectiveness.展开更多
Unlike most plants, members of the genus Solanum produce cholesterol and use this as a precursor for steroidal glycoalkaloids. The production of the compounds begins as a branch from brassinosteroid biosynthesis, whic...Unlike most plants, members of the genus Solanum produce cholesterol and use this as a precursor for steroidal glycoalkaloids. The production of the compounds begins as a branch from brassinosteroid biosynthesis, which produces cholesterol that is further modified to produce steroidal glycoalkaloids. During the cholesterol biosynthesis pathway, genetic engineering could alter the formation of cholesterol from provitamin D3(7-dehydrocholesterol) and produce vitamin D3. Cholesterol is a precursor for many steroidal glycoalkaloids, including a-tomatine and esculeoside A. Alpha-tomatine is consumed by mammals and it can reduce cholesterol content and improve LDL:HDL ratio. When there is a high a-tomatine content, the fruit will have a bitter flavor, which together with other steroidal glycoalkaloids serving as protective and defensive compounds for tomato against insect, fungal, and bacterial pests. These compounds also affect the rhizosphere bacteria by recruiting beneficial bacteria. One of the steroidal glycoalkaloids, esculeoside A increases while fruit ripening. This review focuses on recent studies that uncovered key reactions of the production of cholesterol and steroidal glycoalkaloids in tomato connecting to human health, fruit flavor, and plant defense and the potential application for tomato crop improvement.展开更多
At evaluating the combat effectiveness of the defense system, target′s probability to penetrate the defended area is a primary care taking index. In this paper, stochastic model to compete the probability that targe...At evaluating the combat effectiveness of the defense system, target′s probability to penetrate the defended area is a primary care taking index. In this paper, stochastic model to compete the probability that target penetrates the defended area along any flight path is established by the state analysis and statistical equilibrium analysis of stochastic service system theory. The simulated annealing algorithm is an enlightening random search method based on Monte Carlo recursion, and it can find global optimal solution by simulating annealing process. Combining stochastic model to compete the probability and simulated annealing algorithm, this paper establishes the method to solve problem quantitatively about combat configuration optimization of weapon systems. The calculated result shows that the perfect configuration for fire cells of the weapon is fast found by using this method, and this quantificational method for combat configuration is faster and more scientific than previous one based on principle via map fire field.展开更多
Ballistic missile defense system (BMDS) is important for its special role in ensuring national security and maintaining strategic balance. Research on modeling and simulation of the BMDS beforehand is essential as dev...Ballistic missile defense system (BMDS) is important for its special role in ensuring national security and maintaining strategic balance. Research on modeling and simulation of the BMDS beforehand is essential as developing a real one requires lots of manpower and resources. BMDS is a typical complex system for its nonlinear, adaptive and uncertainty characteristics. The agent-based modeling method is well suited for the complex system whose overall behaviors are determined by interactions among individual elements. A multi-agent decision support system (DSS), which includes missile agent, radar agent and command center agent, is established based on the studies of structure and function of BMDS. Considering the constraints brought by radar, intercept missile, offensive missile and commander, the objective function of DSS is established. In order to dynamically generate the optimal interception plan, the variable neighborhood negative selection particle swarm optimization (VNNSPSO) algorithm is proposed to support the decision making of DSS. The proposed algorithm is compared with the standard PSO, constriction factor PSO (CFPSO), inertia weight linear decrease PSO (LDPSO), variable neighborhood PSO (VNPSO) algorithm from the aspects of convergence rate, iteration number, average fitness value and standard deviation. The simulation results verify the efficiency of the proposed algorithm. The multi-agent DSS is developed through the Repast simulation platform and the constructed DSS can generate intercept plans automatically and support three-dimensional dynamic display of missile defense process.展开更多
Escherichia coli strain K-12 MG1655 has been proposed as an appropriate host strain for industrial production.However,the direct application of this strain suffers from the transformation inefficiency and plasmid inst...Escherichia coli strain K-12 MG1655 has been proposed as an appropriate host strain for industrial production.However,the direct application of this strain suffers from the transformation inefficiency and plasmid instability.Herein,we conducted genetic modifications at a serial of loci of MG1655 genome,generating a robust and universal host strain JW128 with higher transformation efficiency and plasmid stability that can be used to efficiently produce desired chemicals after introducing the corresponding synthetic pathways.Using JW128 as the host,the titer of isobutanol reached 5.76 g/L in shake-flask fermentation,and the titer of lycopene reached 1.91 g/L in test-tube fermentation,40-fold and 5-fold higher than that of original MG1655,respectively.These results demonstrated JW128 is a promising chassis for high-level production of value-added chemicals.展开更多
基金supported jointly by the earmarked fund for CARS-10-GW2the key research and development program of Hainan Province(Grant No.ZDYF2020226)+1 种基金Collaborative innovation center of Nanfan and high-efficiency tropical agriculture,Hainan University(Grant No.XTCX2022NYC21)funding of Hainan University[Grant No.KYQD(ZR)22123]。
文摘Heat stress hinders the growth and productivity of sweetpotato plants,predominantly through oxidative damage to cellular membranes.Therefore,the development of efficient approaches for mitigating heat-related impairments is essential for the long-term production of sweetpotatoes.Melatonin has been recognised for its capacity to assist plants in dealing with abiotic stress conditions.This research aimed to investigate how different doses of exogenous melatonin influence heat damage in sweetpotato plants.Heat stress drastically affected shoot and root fresh weight by 31.8 and 44.5%,respectively.This reduction resulted in oxidative stress characterised by increased formation of hydrogen peroxide(H_(2)O_(2))by 804.4%,superoxide ion(O_(2)^(·-))by 211.5%and malondialdehyde(MDA)by 234.2%.Heat stress also reduced chlorophyll concentration,photosystemⅡefficiency(F_v/F_m)by 15.3%and gaseous exchange.However,pre-treatment with 100μmol L^(-1)melatonin increased growth and reduced oxidative damage to sweetpotato plants under heat stress.In particular,melatonin decreased H_(2)O_(2),O_(2)^(·-)and MDA by 64.8%,42.7%and 38.2%,respectively.Melatonin also mitigated the decline in chlorophyll levels and improved stomatal traits,gaseous exchange and F_(v)/F_(m)(13%).Results suggested that the favorable outcomes of melatonin treatment can be associated with elevated antioxidant enzyme activity and an increase in non-enzymatic antioxidants and osmo-protectants.Overall,these findings indicate that exogenous melatonin can improve heat stress tolerance in sweetpotatoes.This stu dy will assist re searchers in further investigating how melatonin makes sweetpotatoes more resistant to heat stress.
基金supported by the National Natural Science Foundation of China(61272011)
文摘In order to solve the problem that the ripple-effect analy- sis for the operational architecture of air defense systems (OAADS) is hardly described in quantity with previous modeling approaches, a supernetwork modeling approach for the OAADS is put for- ward by extending granular computing. Based on that operational units and links are equal to different information granularities, the supernetwork framework of the OAADS is constructed as a “four- network within two-layer” structure by forming dynamic operating coalitions, and measuring indexes of the ripple-effect analysis for the OAADS are given combining with Laplace spectral radius. In this framework, via analyzing multidimensional attributes which inherit relations between operational units in different granular scales, an extended granular computing is put forward integrating with a topological structure. Then the operation process within the supernetwork framework, including transformation relations be- tween two layers in the vertical view and mapping relations among functional networks in the horizontal view, is studied in quantity. As the application case shows, comparing with previous modeling approaches, the supernetwork model can validate and analyze the operation mechanism in the air defense architecture, and the ripple-effect analysis can be used to confirm the key operational unit with micro and macro viewpoints.
基金supported by the National Natural Science Foundation of China (No. 20777040)the Hi-TechResearch and Development Program (863) of China (No.2007AA061201).
文摘Under the indoor simulant conditions, toxic effects of crude-oil-contaminated soil which was put into aquatic environment on the young fishes Carassius auratus and their hepatic antioxidant system after a 20-d exposure were investigated. Results showed that the relationship between the mortality of C. auratus and the exposed doses could be divided into 3 phases: fishes exposed to the low dose groups (0.5-5.0 g/L) were dead due to the ingestion of crude-oil-contaminated soils in aquatic environment; at the medium dose groups (5.0-25.0 g/L) fishes were dead due to the penetration of toxic substances; at the high dose groups (25.0-50.0 g/L) fishes were dead due to environmental stress. The highest mortality and death speed were found in the 1.0 g/L dose group, and the death speed was sharply increased in the 50.0 g/L dose group in the late phase of exposure. The activities of superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) and the content of malaondialdehyde (MDA) in the hepatic tissues of C. auratus were induced significantly. The activity of SOD was increased and then decreased. It was significantly inhibited in the 50.0 g/L dose group. The activity of CAT was highly induced, and restored to a level which is little more than the control when the exposed doses exceeded 10.0 g/L. The activity of GST was the most sensitive, it was significantly induced in all dose groups, and the highest elevation was up to 6 times in the 0.5 g/L dose group comparing with the control. The MDA content was significantly elevated in the 50.0 g/L dose group, and the changes of the MDA content were opposite with the changes of GST activity.
基金Sponsored by Jiangsu Planned Project for Postdoctoral (0901014B)
文摘The fire distribution can be divided into weapon assignment and firing time scheduling. The criterion of weapon allocation is that a target with greater threat has higher priority. And the criterion of firing time scheduling is that a target can be damaged with the expected probability before a specific time. A fire distribution scheme and a program for the integrated missile-gun air defense system based on a criterion of earlier damage were presented. An example was taken to illustrate its effectiveness.
文摘Various application domains require the integration of distributed real-time or near-real-time systems with non-real-time systems.Smart cities,smart homes,ambient intelligent systems,or network-centric defense systems are among these application domains.Data Distribution Service(DDS)is a communication mechanism based on Data-Centric Publish-Subscribe(DCPS)model.It is used for distributed systems with real-time operational constraints.Java Message Service(JMS)is a messaging standard for enterprise systems using Service Oriented Architecture(SOA)for non-real-time operations.JMS allows Java programs to exchange messages in a loosely coupled fashion.JMS also supports sending and receiving messages using a messaging queue and a publish-subscribe interface.In this article,we propose an architecture enabling the automated integration of distributed real-time and non-real-time systems.We test our proposed architecture using a distributed Command,Control,Communications,Computers,and Intelligence(C4I)system.The system has DDS-based real-time Combat Management System components deployed to naval warships,and SOA-based non-real-time Command and Control components used at headquarters.The proposed solution enables the exchange of data between these two systems efficiently.We compare the proposed solution with a similar study.Our solution is superior in terms of automation support,ease of implementation,scalability,and performance.
文摘Arsenic(As)contaminated food chains have emerged as a serious public concern for humans and animals and are known to affect the cultivation of edible crops throughout the world.Therefore,the present study was designed to investigate the individual as well as the combined effects of exogenous silicon(Si)and sodium nitroprusside(SNP),a nitric oxide(NO)donor,on plant growth,metabolites,and antioxidant defense systems of radish(Raphanus sativus L.)plants under three different concentrations of As stress,i.e.,0.3,0.5,and 0.7 mM in a pot experiment.The results showed that As stress reduced the growth parameters of radish plants by increasing the level of oxidative stress markers,i.e.,malondialdehyde and hydrogen peroxide.However,foliar application of Si(2 mM)and pretreatment with SNP(100μM)alone as well as in combination with Si improved the plant growth parameters,i.e.,root length,fresh and dry weight of plants under As stress.Furthermore,As stress also reduced protein,and metabolites contents(flavonoids,phenolic and anthocyanin).Activities of antioxidative enzymes such as catalase(CAT),ascorbate peroxidase(APX),guaiacol peroxidase(POD),and polyphenol oxidase(PPO),as well as the content of non-enzymatic antioxidants(glutathione and ascorbic acid)decreased under As stress.In most of the parameters in radish,As III concentration showed maximum reduction,as compared to As I and II concentrations.However,the individual and combined application of Si and NO significantly alleviated the As-mediated oxidative stress in radish plants by increasing the protein,and metabolites content.Enhancement in the activities of CAT,APX,POD and PPO enzymes were recorded.Contents of glutathione and ascorbic acid were also enhanced in response to co-application of Si and NO under As stress.Results obtained were more pronounced when Si and NO were applied in combination under As stress,as compared to their individual application.In short,the current study highlights that Si and NO synergistically regulate plant growth through lowering the As-mediated oxidative stress by upregulating the metabolites content,activity of antioxidative enzymes and non-enzymatic antioxidants in radish plants.
文摘The concept of smart power requires to combine soft and hard power. Thus, smart power is a new approach for the US politics towards the Middle East. As a consequence of smart power politics of the US, some newly members of the EU and Turkey has become a part of missile defense system. This is a significant indicator of usage of smart power for the EU members and Turkey. The security policies and practices of the US disclose a necessity for straight allies. For this reason, the relationship between the US, the EU and Turkey may be conceptualize with reference to the concept of smart power. In the case of Missile Defense System, Turkey has agreed to be a participant of this system after signing an agreement with the US. After that, Turkish government has confronted with some interior and exterior political difficulties. One of the most important difficulties is the interior resistance of missile defense system's Kiirecik Radar Station and its usage in Turkey. Another important point is the question of control of Turkish National Security and Defense strategy. In that respect, the US government's smart power applications may be included in the establishment of the radar station. The EU has also been included in that strategy. This paper will argue smart power practices of the US, the EU and Turkey with reference to comparative practices of power politics and the case of Missile Defense System. In this way, a comprehensive and system-type assessment of possible responses and the change in relations between stakeholder states not only in the issue of a set-up of a Turkish radar station, but on a broader range of international "hard" security balance will be demonstrated.
文摘Marine zooplankton responds sensitively to elevated seawater CO_2 concentration. However, the underlying physiological mechanisms have not been studied well. We therefore investigated the effects of elevated CO_2concentration(0.08%, 0.20%, 0.50% and 1.00%) on antioxidant defense components, as well as two detoxification enzymes of Calanus sinicus(copepod). The results showed that glutathione peroxidase(GPx) activity exposed to CO_2-acidified seawater was significantly stimulated while other antioxidant components, including glutathione-Stransferase(GST) activity, superoxide dismutase(SOD) activity decreased significantly with reduced glutathione(GSH) level and GSH/oxidized glutathione(GSSG) value. CO_2-acidified seawater exhibited stimulatory effects on adenosine triphosphatase(ATPase) activity and acetylcholinesterase(Ach E) activity was inhibited. Moreover, the results of principal component analysis indicated that 75.93% of the overall variance was explained by the first two principal components. The elevated CO_2 concentration may affect the metabolism and survivals of copepods through impacts these enzymes activities. Further studies are needed to focus on the synergistic effects of elevated CO_2 concentration and other environmental factors on copepods.
基金This work was supported by National Natural Science Foundation of China(No.61971026)the Fundamental Research Funds for the Central Universities(No.FRF-TP-18-008A3).
文摘In this paper,the security problem for the multi-access edge computing(MEC)network is researched,and an intelligent immunity-based security defense system is proposed to identify the unauthorized mobile users and to protect the security of whole system.In the proposed security defense system,the security is protected by the intelligent immunity through three functions,identification function,learning function,and regulation function,respectively.Meanwhile,a three process-based intelligent algorithm is proposed for the intelligent immunity system.Numerical simulations are given to prove the effeteness of the proposed approach.
基金Project(41161057)supported by the National Natural Science Foundation of ChinaProject(Guikezhuan 14122008-2)supported by Guangxi Provincial Science and Technology Development,China+2 种基金Project(2014GXNSFAA118303)supported by the Natural Science Foundation of Guangxi Province,ChinaProjects(YRHJ15K002,YRHJ15Z026)supported by Key Laboratory of Karst Ecology and Environment Change of Guangxi Normal University,ChinaProject(2016JJ6135)supported by the Natural Science Foundation of Hunan Province,China
文摘The response of enzyme and non-enzymatic antioxidants of Mn hyperaccumuator, Polygonum hydropiper (P. hydropiper), to Mn stress was studied using hydroponics culture experiments to explore the mechanism of Mn tolerance in this species. Results showed that both chlorophyll and carotenoid contents significantly (p〈0.05) decreased with increasing Mn treatment levels (0, 0.5, 1, 2, 4, and 8 mg/L) in hydroponics. The concentrations of malondialdehyde (MDA) and hydrogen peroxide (H202) in the root and shoot of P hydropiper were accumulated under Mn stress. Meanwhile, the anti-oxidative functions of several important enzymes, including superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and peroxidase (POD) in plants were stimulated by Mn spike in leaves and roots, especially at low Mn stress; while sulfhydryl group (--SH) and glutathion (GSH) were likely involved in Mn detoxification ofP. hydropiper under high Mn stress.
基金supported by the National Natural Science Foundation of China(7170120971771216)+1 种基金Shaanxi Natural Science Foundation(2019JQ-250)China Post-doctoral Fund(2019M653962)
文摘In order to cope with the increasing threat of the ballistic missile(BM)in a shorter reaction time,the shooting policy of the layered defense system needs to be optimized.The main decisionmaking problem of shooting optimization is how to choose the next BM which needs to be shot according to the previous engagements and results,thus maximizing the expected return of BMs killed or minimizing the cost of BMs penetration.Motivated by this,this study aims to determine an optimal shooting policy for a two-layer missile defense(TLMD)system.This paper considers a scenario in which the TLMD system wishes to shoot at a collection of BMs one at a time,and to maximize the return obtained from BMs killed before the system demise.To provide a policy analysis tool,this paper develops a general model for shooting decision-making,the shooting engagements can be described as a discounted reward Markov decision process.The index shooting policy is a strategy that can effectively balance the shooting returns and the risk that the defense mission fails,and the goal is to maximize the return obtained from BMs killed before the system demise.The numerical results show that the index policy is better than a range of competitors,especially the mean returns and the mean killing BM number.
文摘Salinity is one of the most severe abiotic stresses for crop production.The present study investigates the salinityinduced modulation in growth indicators,morphology and movement of stomata,photosynthetic pigments,activity of carbonic anhydrase as well as nitrate reductase,and antioxidant systems in two varieties of chickpea(Pusa-BG5023,and Pusa-BGD72).On 20^(th) day of sowing,plants were treated with varying levels of NaCl(0,50,100,150 and 200 mM)followed by sampling on 45 days of sowing.Recorded observations on both the varieties reveal that salt stress leads to a significant decline in growth,dry biomass,leaf area,photosynthetic pigments,protein content,stomatal behavior,cell viability,activity of nitrate reductase and carbonic anhydrase with the rise in the concentration of salt.However,quantitatively these changes were less in Pusa-BG5023 as compared to Pusa-BGD72.Furthermore,salinity-induced oxidative stress enhanced malondialdehyde content,superoxide radicals,foliar proline content,and the enzymatic activities of superoxide dismutase,catalase,and peroxidase.The variety Pusa-BGD72 was found more sensitive than Pusa-BG5023 to salt stress.Out of different graded concentrations(50,100,150 and 200 mM)of sodium chloride,50 mM was least toxic,and 200 mM was most damaging.The differential behavior of these two varieties measured in terms of stomatal behavior,cell viability,photosynthetic pigments,and antioxidant defense system can be used as prospective indicators for selection of chickpea plants for salt tolerance and sensitivity.
基金This research was funded by Korea Environmental Industry&Technology Institute(KEITI),Grant Number RE202101551and The APC was funded by Ministry of Environment(ME).
文摘As a large amount of data needs to be processed and speed needs to be improved,edge computing with ultra-low latency and ultra-connectivity is emerging as a new paradigm.These changes can lead to new cyber risks,and should therefore be considered for a security threat model.To this end,we constructed an edge system to study security in two directions,hardware and software.First,on the hardware side,we want to autonomically defend against hardware attacks such as side channel attacks by configuring field programmable gate array(FPGA)which is suitable for edge computing and identifying communication status to control the communication method according to priority.In addition,on the software side,data collected on the server performs end-to-end encryption via symmetric encryption keys.Also,we modeled autonomous defense systems on the server by using machine learning which targets to incoming and outgoing logs.Server log utilizes existing intrusion detection datasets that should be used in real-world environments.Server log was used to detect intrusion early by modeling an intrusion prevention system to identify behaviors that violate security policy,and to utilize the existing intrusion detection data set that should be used in a real environment.Through this,we designed an efficient autonomous defense system that can provide a stable system by detecting abnormal signals from the device and converting them to an effective method to control edge computing,and to detect and control abnormal intrusions on the server side.
基金This research was supported by the National Social Science Foundation of China, and its approval number is 03CJY011
文摘: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.
基金supported by the National Natural Science Foundation of China(Grant No.32061143012 to A.Z.,32101352 to X.H.).
文摘Marine ecosystems are facing escalating environmental fluctuations owing to climate change and human activities,imposing pressures on marine species.To withstand recurring environmental challenges,marine organisms,especially benthic species lacking behavioral choices to select optimal habitats,have to utilize well-established strategies such as the antioxidant defense system(ADS)to ensure their survival.Therefore,understanding of the mechanisms governing the ADS-based response is essential for gaining insights into adaptive strategies for managing environmental challenges.Here we conducted a com-parative analysis of the physiological and transcriptional responses based on the ADS during two rounds of'hypersalinity-recovery'challenges in two model congeneric invasive ascidians,Ciona robusta and C.savignyi.Our results demonstrated that C.savignyi exhibited higher tolerance and resistance to salinity stresses at the physiological level,while C.robusta demonstrated heightened responses at the transcriptional level.We observed distinct transcriptional responses,particularly in the utilization of two superoxide dismutase(SOD)isoforms.Both Ciona species developed physiological stress memory with elevated total SOD(T-SOD)and glutathione(GSH)responses,while only C.robusta demonstrated transcriptional stress memory.The regulatory distinctions within the Nrf2-Keap1 signalling pathway likely explain the formation disparity of transcriptional stress memory between both Ciona species.These findings support the'context-dependent stress memory hypothesis',emphasizing the emergence of species-specific stress memory at diverse regulatory levels in response to recurrent environmental challenges.Our results enhance our understanding of the mechanisms of environmental challenge manage-ment in marine species,particularly those related to the ADS.
基金supported by Systematic Major Project of China State Railway Group Corporation Limited(Grant Number:P2023W002).
文摘The development of Intelligent Railway Transportation Systems necessitates incorporating privacy-preserving mechanisms into AI models to protect sensitive information and enhance system efficiency.Federated learning offers a promising solution by allowing multiple clients to train models collaboratively without sharing private data.However,despite its privacy benefits,federated learning systems are vulnerable to poisoning attacks,where adversaries alter local model parameters on compromised clients and send malicious updates to the server,potentially compromising the global model’s accuracy.In this study,we introduce PMM(Perturbation coefficient Multiplied by Maximum value),a new poisoning attack method that perturbs model updates layer by layer,demonstrating the threat of poisoning attacks faced by federated learning.Extensive experiments across three distinct datasets have demonstrated PMM’s ability to significantly reduce the global model’s accuracy.Additionally,we propose an effective defense method,namely CLBL(Cluster Layer By Layer).Experiment results on three datasets have confirmed CLBL’s effectiveness.
文摘Unlike most plants, members of the genus Solanum produce cholesterol and use this as a precursor for steroidal glycoalkaloids. The production of the compounds begins as a branch from brassinosteroid biosynthesis, which produces cholesterol that is further modified to produce steroidal glycoalkaloids. During the cholesterol biosynthesis pathway, genetic engineering could alter the formation of cholesterol from provitamin D3(7-dehydrocholesterol) and produce vitamin D3. Cholesterol is a precursor for many steroidal glycoalkaloids, including a-tomatine and esculeoside A. Alpha-tomatine is consumed by mammals and it can reduce cholesterol content and improve LDL:HDL ratio. When there is a high a-tomatine content, the fruit will have a bitter flavor, which together with other steroidal glycoalkaloids serving as protective and defensive compounds for tomato against insect, fungal, and bacterial pests. These compounds also affect the rhizosphere bacteria by recruiting beneficial bacteria. One of the steroidal glycoalkaloids, esculeoside A increases while fruit ripening. This review focuses on recent studies that uncovered key reactions of the production of cholesterol and steroidal glycoalkaloids in tomato connecting to human health, fruit flavor, and plant defense and the potential application for tomato crop improvement.
文摘At evaluating the combat effectiveness of the defense system, target′s probability to penetrate the defended area is a primary care taking index. In this paper, stochastic model to compete the probability that target penetrates the defended area along any flight path is established by the state analysis and statistical equilibrium analysis of stochastic service system theory. The simulated annealing algorithm is an enlightening random search method based on Monte Carlo recursion, and it can find global optimal solution by simulating annealing process. Combining stochastic model to compete the probability and simulated annealing algorithm, this paper establishes the method to solve problem quantitatively about combat configuration optimization of weapon systems. The calculated result shows that the perfect configuration for fire cells of the weapon is fast found by using this method, and this quantificational method for combat configuration is faster and more scientific than previous one based on principle via map fire field.
文摘Ballistic missile defense system (BMDS) is important for its special role in ensuring national security and maintaining strategic balance. Research on modeling and simulation of the BMDS beforehand is essential as developing a real one requires lots of manpower and resources. BMDS is a typical complex system for its nonlinear, adaptive and uncertainty characteristics. The agent-based modeling method is well suited for the complex system whose overall behaviors are determined by interactions among individual elements. A multi-agent decision support system (DSS), which includes missile agent, radar agent and command center agent, is established based on the studies of structure and function of BMDS. Considering the constraints brought by radar, intercept missile, offensive missile and commander, the objective function of DSS is established. In order to dynamically generate the optimal interception plan, the variable neighborhood negative selection particle swarm optimization (VNNSPSO) algorithm is proposed to support the decision making of DSS. The proposed algorithm is compared with the standard PSO, constriction factor PSO (CFPSO), inertia weight linear decrease PSO (LDPSO), variable neighborhood PSO (VNPSO) algorithm from the aspects of convergence rate, iteration number, average fitness value and standard deviation. The simulation results verify the efficiency of the proposed algorithm. The multi-agent DSS is developed through the Repast simulation platform and the constructed DSS can generate intercept plans automatically and support three-dimensional dynamic display of missile defense process.
基金The work finished in Beijing Institute of Technology was supported by the National Key R&D Program of China(grant No.2019YFA0904104)the National Natural Science Foundation of China(Grant No.21676026)the Fundamental Research Funds for the Central Universities.
文摘Escherichia coli strain K-12 MG1655 has been proposed as an appropriate host strain for industrial production.However,the direct application of this strain suffers from the transformation inefficiency and plasmid instability.Herein,we conducted genetic modifications at a serial of loci of MG1655 genome,generating a robust and universal host strain JW128 with higher transformation efficiency and plasmid stability that can be used to efficiently produce desired chemicals after introducing the corresponding synthetic pathways.Using JW128 as the host,the titer of isobutanol reached 5.76 g/L in shake-flask fermentation,and the titer of lycopene reached 1.91 g/L in test-tube fermentation,40-fold and 5-fold higher than that of original MG1655,respectively.These results demonstrated JW128 is a promising chassis for high-level production of value-added chemicals.