Non-fragile observer-based passive control for descriptor systems with time-delay

This paper investigates the problem of non-fragile observer-based passive control for descriptor systems with time-delay. The perturbations in both the control gain and observer gain of the observer-based controller are considered. For the cases of the additive perturbations and multiplicative perturbations, sufficient conditions are given such that the closed-loop systems are admissible and passive with dissipation η. The observer-based controller gains could be obtained from the solutions of linear matrix inequalities （LMIs）. Moreover, the maximum dissipation of the system is provided. Simulation examples are given to show the effectiveness of the deign methods.

Stability analysis and stabilization for discrete-time singular delay systems

Stability analysis and stabilization for discrete-time singular delay systems are addressed,respectively.Firstly,a sufficient condition for regularity,causality and stability for discrete-time singular delay systems is derived.Then,by applying the skill of matrix theory,the state feedback controller is designed to guarantee the closed-loop discrete-time singular delay systems to be regular,casual and stable.Finally,numerical examples are given to demonstrate the effectiveness of the proposed method.

Quantized dynamic output feedback control for networked control systems

The problem of the quantized dynamic output feedback controller design for networked control systems is mainly discussed. By using the quantized information of the system measurement output and the control input, a novel networked control system model is described. This model includes many networkinduced features, such as multi-rate sampled-data, quantized signal, time-varying delay and packet dropout. By constructing suitable Lyapunov-Krasovskii functional, a less conservative stabilization criterion is established in terms of linear matrix inequalities. The quantized control strategy involves the updating values of the quantizer parameters μi（i = 1, 2）（μi take on countable sets of values which dependent on the information of the system measurement outputs and the control inputs）. Furthermore, a numerical example is given to illustrate the effectiveness of the proposed method.

Non-fragile guaranteed cost control for uncertain neutral large-scale interconnected systems

This paper focuses on the problem of non-fragile decentralized guaranteed cost control for uncertain neutral large-scale interconnected systems with time-varying delays in state,control input and interconnections.A novel scheme,viewing the interconnections with time-varying delays as effective information but not disturbances,is developed.Based on Lyapunov stability theory,using various techniques of decomposing and magnifying matrices,a design method of the non-fragile decentralized guaranteed cost controller for unperturbed neutral large-scale interconnected systems is proposed and the guaranteed cost is presented.The further results are derived for the uncertain case from the criterion of unperturbed neutral large-scale interconnected systems.Finally,an illustrative example shows that the results are significantly better than the existing results in the literatures.

Purchase willingness of new energy vehicles: A case study in Jinan City of China

Speeding up the promotion of new energy vehicles is an important measure to optimize the energy structure,promote energy conservation and emission reduction,and develop the economy sustainability.The research uses a questionnaire survey to analyze the residents’willingness to purchase new energy vehicles in Jinan Gty of China,and utilizes the binomial logistic regression model and Global Moran's I to explain the impact of three factors(including responden ts'personal characteristics and subjective cognition,products,and social environment)on the purchase willingness of new energy vehicles.According to the survey,75.12%of the responden ts consider buying new energy vehicles in the future,but only 11.66%of the respondents know new energy vehicles well.It can be seen that the respondents in Jinan City generally have an insufficient understanding of new energy vehicles.It may lead to a decline in residents’trust in new energy vehicles,which will in turm affect their purchase willingness.Based on the survey,we find that women who live far from the city center enjoy high incomes and have a low-carbon awareness,generally exhibit a higher willingness to purchase new energy vehicles.Spatial distribution of the purchase willingness has certain aggregation characteristics,showing a positive spatial correlation pattern.Purchase willingness has a certain positive diffusion effect in space,and areas with a higher purchase willingness have a positive driving effect on their surrounding regions.Spatial distribution of the purchase willingness can be used as one of the breakthroughs in promoting new energy vehicles.In addition,safety,price,after-sales service,and infrastruicture of new energy vehicles are important determinants of people's purchase willingness.Among the types of subsidies,financial subsidy is most effective on the residents’purchase wilingness.Our research provides an impor tant information for the promotion of new energy vehicles in the region.

State feedback control of network-based systems with packet disordering

A new method that stabilizes network-based systems with both bounded delay and packet disordering is discussed under the state feedback controller. A novel model, fully describing the dynamic characteristic of network-based systems with packet disordering, is constructed. Different from the existing models of network-based systems, the number of delay items is time-varying in the model proposed. Further, this model is converted into a parameter-uncertain discrete-time system with time-varying delay item numbers in terms of matrix theory. Moreover, the less conservative stability condition is obtained by avoiding utilisation of Moon et al.’ inequality and bounding inequalities for quadratic functional terms. By solving a minization problem based on linear matrix inequalities, the state feedback controller is presented. A numerical example is given to illustrate the effectiveness of the proposed method.

High-quality assembled and annotated genomes of Nicotiana tabacum and Nicotiana benthamiana reveal chromosome evolution and changes in defense arsenals

Nicotiana tabacum and Nicotiana benthamiana are widely used models in plant biology research.However,genomic studies of these species have lagged.Here we report the chromosome-level reference genome assemblies for N.benthamiana and N.tabacum with an estimated 99.5%and 99.8%completeness,respec-tively.Sensitive transcription start and termination site sequencing methods were developed and used for accurate gene annotation in N.tabacum.Comparative analyses revealed evidence for the parental origins and chromosome structural changes,leading to hybrid genome formation of each species.Interestingly,theantiviral silencinggenesRDR1,RDR6,DCL2,DCL3,andAGO2were lost from one or both subgenomes in N.benthamiana,while both homeologs were kept in N.tabacum.Furthermore,the N.benthamiana genome encodes fewer immune receptors and signaling components than that of N.tabacum.These find-ings uncover possible reasons underlying the hypersusceptible nature of N.benthamiana.We developed the user-friendly Nicomics(http:/lifenglab.hzau.edu.cn/Nicomics/)web server to facilitate better use of Nicotiana genomic resources as well as gene structure and expression analyses.

Eligibility of C-BIOPRED severe asthma cohort for type-2 biologic therapies

To the Editor:Patients with severe persistent asthma experience greater morbidity with more impairment in quality of life despite higher use of health care resources and being treated with existing asthma treatments such as inhaled corticosteroids and b-agonists,and sometimes oral corticosteroid(OCS)therapy.Type-2(T2)high asthma has been identified as a phenotype that responds to targeted T2 biologic therapies such as anti-IgE,anti-interleukin(IL)5,or anti-IL5Ra and anti-IL4Ra monoclonal antibodies,which are currently available in Europe and North America,and are currently introduced in the rest of the world.[1]

Resveratrol activation of SIRT1/MFN2 can improve mitochondria function,alleviating doxorubicin-induced myocardial injury

Background Doxorubicin is a widely used cytotoxic chemotherapy agent for treating different malignancies.However,its use is associated with dose-dependent cardiotoxicity,causing irreversible myocardial damage and significantly reducing the patient's quality of life and survival.In this study,an animal model of doxorubicin-induced cardiomyopathy was used to investigate the pathogenesis of doxorubicin-induced myocardial injury.This study also investigated a possible treatment strategy for alleviating myocardial injury through resveratrol therapy in vitro.Methods Adult male C57BL/6J mice were randomly divided into a control group and a doxorubicin group.Body weight,echocardiography,surface electrocardiogram,and myocardial histomorphology were measured.The mechanisms of doxorubicin cardiotoxicity in H9c2 cell lines were explored by comparing three groups(phosphate-buffered saline,doxorubicin,and doxorubicin with resveratrol).Results Compared to the control group,the doxorubicin group showed a lower body weight and higher systolic arterial pressure,associated with reduced left ventricular ejection fraction and left ventricular fractional shortening,prolonged PR interval,and QT interval.These abnormalities were associated with vacuolation and increased disorder in the mitochondria of cardiomyocytes,increased protein expression levels of α-smooth muscle actin and caspase 3,and reduced protein expression levels of Mitofusin2(MFN2)and Sirtuin1(SIRT1).Compared to the doxorubicin group,doxorubicin+resveratrol treatment reduced caspase 3 and manganese superoxide dismutase,and increased MFN2 and SIRT1 expression levels.Conclusion Doxorubicin toxicity leads to abnormal mitochondrial morphology and dysfunction in cardiomyocytes and induces apoptosis by interfering with mitochondrial fusion.Resveratrol ameliorates doxorubicin-induced cardiotoxicity by activating SIRT1/MFN2 to improve mitochondria function.

RepDDNet:a fast and accurate deforestation detection model with high-resolution remote sensing image

Forest is the largest carbon reservoir and carbon absorber on earth.Thus,mapping forest cover change accurately is of great significance to achieving the global carbon neutrality goal.Accurate forest change information could be acquired by deep learning methods using high-resolution remote sensing images.However,deforestation detection based on deep learning on a large-scale region with high-resolution images required huge computational resources.Therefore,there was an urgent need for a fast and accurate deforestation detection model.In this study,we proposed an interesting but effective re-parameterization deforestation detection model,named RepDDNet.Unlike other existing models designed for deforestation detection,the main feature of RepDDNet was its decoupling feature,which means that it allowed the multi-branch structure in the training stages to be converted into a plain structure in the inference stage,thus the computation efficiency can be significantly improved in the inference stage while maintaining the accuracy unchanged.A large-scale experiment was carried out in Ankang city with 2-meter high-resolution remote sensing images(the total area of it was over 20,000 square kilometers),and the result indicated that the model computation efficiency could be improved by nearly 30%compared with the model without re-parameterization.Additionally,compared with other lightweight models,RepDDNet also displayed a trade-off between accuracy and computation efficiency.

1,4-吡啶硫内鎓盐在有机合成中的研究与应用

1,4-吡啶硫内鎓盐是一类重要的氮硫杂合成子,其中的吡啶片段既可以作为离去基团,也可以作为亲电反应位点参与反应,构建多种类型的氮硫杂骨架.因此,近年来1,4-吡啶硫内鎓盐在含氮、含硫杂环化合物的合成应用中受到了极大的关注.基于此,系统综述了1,4-吡啶硫内鎓盐在两种反应模式([3+m]和[5+m]环合反应)下构建氮硫杂环的研究进展,总结了其在环合反应及杂环化学中的应用,并对该领域的研究前景进行了展望.

Potential therapeutic effects of dipyridamole in the severely ill patients with COVID-19

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection can cause acute respiratory distress syndrome,hypercoagulability,hypertension,and multiorgan dysfunction.Effective antivirals with safe clinical profile are urgently needed to improve the overall prognosis.In an analysis of a randomly collected cohort of 124 patients with COVID-19,we found that hypercoagulability as indicated by elevated concentrations of D-dimers was associated with disease severity.By virtual screening of a U.S.FDA approved drug library,we identified an anticoagulation agent dipyridamole(DIP)in silico,which suppressed SARS-CoV-2 replication in vitro.In a proof-of-concept trial involving 31 patients with COVID-19,DIP supplementation was associated with significantly decreased concentrations of D-dimers(P<0.05),increased lymphocyte and platelet recovery in the circulation,and markedly improved clinical outcomes in comparison to the control patients.In particular,all 8 of the DIP-treated severely ill patients showed remarkable improvement:7 patients(87.5%)achieved clinical cure and were discharged from the hospitals while the remaining 1 patient(12.5%)was in clinical remission.

Variable structure control for three-variable autocatalytic reaction

In this paper, two irreversible exothermic autocatalytic reactions which carry out in continuous stirred tank reactor （CSTR） are considered. A differential-algebraic system is applied to model these chemical reactions. The stability and the dynamic behavior are studied for the differential-algebraic system. The Hopf bifurcation appears when the parameter exceeds a critical value. In order to eliminate this complex behavior, the differential-algebraic system is described by a single-input and single-output system with parameter varying within definite intervals, and then variable structure control with sliding mode based on a special power reaching law is designed to stabilize this chemical system. Numerical simulations are given to illustrate the effectiveness of the method.

Hopf analysis of a differential-algebraic predator-prey model with Allee effect and time delay

A differential-algebraic prey--predator model with time delay and Allee effect on the growth of the prey population is investigated. Using differential-algebraic system theory, we transform the prey predator model into its normal form and study its dynamics in terms of local analysis and Hopf bifurcation. By analyzing the associated characteristic equation, it is observed that the model undergoes a Hopf bifurcation at some critical value of time delay. In particular, we study the direction of Hopf bifurcation and the stability of bifurcated periodic solutions, and an explicit algorithm is given by applying the normal form theory and the center manifold reduction for functional differential equations. Finally, numerical simulations supporting the theoretical analysis are also included.

DYNAMICAL ANALYSIS AND CONTROL IN A DELAYED DIFFERENTIAL-ALGEBRAIC BIO-ECONOMIC MODEL WITH STAGE STRUCTURE AND DIFFUSION

Nowadays, biological resource in prey-predator ecosystem is commercially harvested and sold with aim of achieving economic interest. Furthermore, harvest effort is usually influ- enced by variation of economic interest of harvesting and spatial heterogeneous environ- ment. In this paper, a delayed differential-algebraic bio-economic model is proposed, which is utilized to investigate interaction and coexistence mechanism of biological pop- ulation in the harvested ecosystem due to the variation of economic interest of harvesting as well as the change of population spatial diffusion and gestation delay. Local stability analysis of the proposed model without gestation delay and diffusion reveals that there is a phenomenon of singularity induced bifurcation due to the variation of economic interest of harvesting, and state feedback controllers are designed to stabilize the pro- posed model at the interior equilibrium. Furthermore, local stability of the proposed model with gestation delay and diffusion is studied, which reveals that the interior equi- librium loses its stability at some critical values of gestation delay and corresponding cycle occurs. It is also shown that population spatial diffusion and harvesting have a stabilizing effect on population dynamics. Finally, numerical simulations are carried out to show consistency with theoretical analysis obtained in this paper.

Ionic iron(III) complex of aryloxo-linked bis(imidazolium)cations: efficient and recyclable catalyst for aryl Grignard cross-coupling of alkyl chlorides

A novel phenol-linked bis(imidazolium) salt,H3LCl2(L = O-4-C(CH3)3-C6H2-2,6-di[CH2{C(NCHCHNAr)}]2, Ar = 2,6-diisopropylphenyl, 1), was designed and used to prepare an ionic iron(III) complex [H2L][Fe Cl4](2).Complex 2 was a highly efficient catalyst for aryl Grignard cross-coupling of alkyl chlorides bearing b-hydrogens.Furthermore, complex 2 was reusable and could be reused in at least eight times without significant loss in catalytic activity.

A SINGULAR BIOECONOMIC MODEL WITH DIFFUSION AND TIME DELAY

This paper studies a prey-predator singular bioeconomic system with time delay and diffusion, which is described by differential-algebraic equations. For this system without diffusion, there exist three bifurcation phenomena： Transcritical bifurcation, singularity induced bifurcation, and Hopf bifurcation. Compared with other biological systems described by differential equations, singularity induced bifurcation only occurs in singular system and usually links with the expansion of population. When the diffusion is present, it is shown that the positive equilibrium point loses its stability at some critical values of diffusion rate and periodic oscillations occur due to the increase of time delay. Furthermore, numerical simulations illustrate the effectiveness of results and the related biological implications are discussed.

CHAOS ANALYSIS AND CONTROL FOR A CLASS OF SIR EPIDEMIC MODEL WITH SEASONAL FLUCTUATION

In this paper, the problems of chaos and chaos control for a class of susceptible-infected- removed （SIR） epidemic model with seasonal fluctuation are investigated. The season- ality in outbreak is natural among infectious diseases, as the common influenza, A type H1N1 influenza and so on. It is shown that there exist chaotic phenomena in the epidemic model. Furthermore, the tracking control method is used to control chaotic motions in the epidemic model. A feedback controller is designed to achieve tracking of an ideal out- put. Thus, the density of infected individuals can converge to zero, in other words, thedisease can be disappeared. Finally, numerical simulations illustrate that the controller is effective.

GENERALIZED PREDICTIVE CONTROL FOR DIFFERENCE-ALGEBRAIC BIOLOGICAL ECONOMIC SYSTEMS

In this paper, a nonlinear difference-algebraic system is used to model some populations with stage structure when the harvest behavior and the economic interest are considered. The stability analysis is studied at the equilibrium points. After the non- linear difference-algebraic system is changed into a linear system with the unmodeled dynamics, a generalized predictive controller with feedforward compensator is designed to stabilize the system. Adaptive-network-based fuzzy inference system （ANFIS） is used to make the unmodeled dynamic compensated. An example illustrates the effectiveness of the proposed control method.

PASSIVE CONTROL OF HUMAN BODY COMPLEX SINGULAR SYSTEMS

Due to the complexity of interaction among constituents inside the whole system, it is difficult to establish accurate mathematics models to describe and analyze the complex systems exactly. There are few attempts concerning on the moving process of endocrine disruptor in human bodies, which have been the polluted material worldwide related to the reproduction, existence and development of human being. Focusing on such two challenging issues, a multi-compartment model of endocrine disruptor Benzene moving in the human body complex system is established in this paper. Furthermore, passivity of this model is described systematically. A feedback controller for this descriptor biological complex system is used under the station of strict passivity, and an example of the controller is given for a particular instantiation of the model.