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Analyzing a generalized pest-natural enemy model with nonlinear impulsive control

Changtong Li, Sanyi Tang
2018 Open Mathematics  
Due to resource limitation, nonlinear impulsive control tactics related to integrated pest management have been proposed in a generalized pest-natural enemy model, which allows us to address the effects of nonlinear pulse control on the dynamics and successful pest control. The threshold conditions for the existence and global stability of pest-free periodic solution are provided by Floquet theorem and analytic methods. The existence of a nontrivial periodic solution is confirmed by showing the
more » ... existence of nontrivial fixed point of the stroboscopic mapping determined by time snapshot, which equals to the common impulsive period. In order to address the applications of generalized results and to reveal how the nonlinear impulses affect the successful pest control, as an example the model with Holling II functional response function is investigated carefully. The main results reveal that the pest free periodic solution and a stable interior positive periodic solution can coexist for a wide range of parameters, which indicates that the local stability does not imply the global stability of the pest free periodic solution when nonlinear impulsive control is considered, and consequently the resource limitation (i.e. nonlinear control) may result in difficulties for successful pest control.
doi:10.1515/math-2018-0114 fatcat:yvbr3clkhvb6bfwxvftjyraoqe

Preparation and Properties of Cyanobacteria-Based Carbon Quantum Dots/Polyvinyl Alcohol/ Nanocellulose Composite

Li Xu, Ying Li, Shiyu Gao, Yue Niu, Huaxuan Liu, Changtong Mei, Jiabin Cai, Changyan Xu
2020 Polymers  
Blue luminescent carbon quantum dots (CQDs) were prepared from cyanobacteria by a hydrothermal method. The PL quantum yields of the obtained CQDs was 5.30%. Cyanobacteria-based carbon quantum dots/polyvinyl alcohol/nanocellulose composite films were prepared, which could emit bright blue under UV light. FTIR characterization showed that the composite films had hydroxyl groups on the surface and no new groups were formed after combining the three materials. The photoluminescence (PL) spectra
more » ... aled that the emission of the prepared CQDs was excitation dependent. Studies on the water resistance performance and light barrier properties of the composite films showed that they possessed higher water resistance properties and better UV/infrared light barrier properties. Therefore, we report the cyanobacteria-based carbon quantum dots/polyvinyl alcohol/nanocellulose composite films have the potential to be applied in flexible packaging materials, anti-fake materials, UV/infrared light barrier materials and so on.
doi:10.3390/polym12051143 pmid:32429528 fatcat:ors6edrvyrbezo7id3p5ejo5x4

Evolution of cellular structures on oblique detonation surfaces

Honghui Teng, Hoi Dick Ng, Kang Li, Changtong Luo, Zonglin Jiang
2015 Combustion and Flame  
Using numerical simulation Li et al.  ... 
doi:10.1016/j.combustflame.2014.07.021 fatcat:wwlatrkg55efdfqngz5ftgbo34

Complex Dynamics of Beddington–DeAngelis-Type Predator-Prey Model with Nonlinear Impulsive Control

Changtong Li, Xiaozhou Feng, Yuzhen Wang, Xiaomin Wang, Xinzhu Meng
2020 Complexity  
According to resource limitation, a more realistic pest management is that the impulsive control actions should be adjusted according to the densities of both pest and natural enemy in the field, which result in nonlinear impulsive control. Therefore, we have proposed a Beddington–DeAngelis interference predator-prey model concerning integrated pest management with both density-dependent pest and natural enemy population. We find that the pest-eradication periodic solution is globally stable if
more » ... the impulsive period is less than the critical value by Floquet theorem. The condition of permanent is established, and a stable positive periodic solution appears via a supercritical bifurcation by bifurcation theorem. Finally, in order to investigate the effects of those nonlinear control strategies on the successful pest control, the bifurcation diagrams showed that the model exists with very complex dynamics. Consequently, the resource limitation may result in pest outbreak in complex ways, which means that the pest control strategies should be carefully designed.
doi:10.1155/2020/8829235 fatcat:z3ci25yne5fvjndckq6lfyllqy

The Research Progress of Machining Mechanisms in Milling Wood-based Materials

Weihua Wei, Yuantong Li, Tongming Xue, Shiyuan Tao, Changtong Mei, Wandong Zhou, Jian Wang, Tongyue Wang
2017 BioResources  
Li et al. (2003) took the coating treatment on the surface of P30 carbide tools through Capacitive Voltage Divider (CVD) and Physical Vapor Deposition (PVD), used them to cut high-density fiberboard,  ... 
doi:10.15376/biores.13.1.wei fatcat:oxdo3ktm4jc2veqaya2kmkdhku

Analysis of Key Elements of Truss Structures Based on the Tangent Stiffness Method

Jian Feng, Changtong Li, Yixiang Xu, Qian Zhang, Fang Wang, and Jianguo Cai
2020 Symmetry  
Li et al. [20] proposed a new method to quantify robustness and considered the dynamic effects and the internal force redistribution within a frame structure.  ... 
doi:10.3390/sym12061008 fatcat:4e3k4wqodbf7pls4km6hnitdkq

Rapid microwave activation of waste palm into hierarchical porous carbons for supercapacitors using biochars from different carbonization temperatures as catalysts

Chaozheng Liu, Weimin Chen, Meichun Li, Shu Hong, Wanzhao Li, Mingzhu Pan, Qinglin Wu, Changtong Mei
2019 RSC Advances  
A rapid, simple and cost-effective approach to prepare hierarchical porous carbons (PCs) for supercapacitors is reported by microwave activation of abundant and low-cost waste palm, biochar (BC) and KOH.
doi:10.1039/c9ra03031j pmid:35519395 pmcid:PMC9065327 fatcat:ifrgm2euffhnpbovfcpbtt4mgy

Global Bifurcation Structure of a Predator-Prey System with a Spatial Degeneracy and B-D Functional Response

Xiaozhou Feng, Changtong Li, Hao Sun, Yuzhen Wang, Abdel-Haleem Abdel-Aty
2021 Complexity  
In a paper [21] , López-Gómez and Sabina de Lis have proved that du a /da converges uniformly to ∞ with a ⟶ λ Ω 0 1 on any compact subset of Ω 0 .  ... 
doi:10.1155/2021/9970255 fatcat:44i3v4xvrjgl3ktisztms7xuo4

Electrospun Poly(Ethylene Oxide) Fibers Reinforced with Poly (Vinylpyrrolidone) Polymer and Cellulose Nanocrystals [chapter]

Qinglin Wu, Changtong Mei, Xiuqiang Zhang, Tingzhou Lei, Zhen Zhang, Meichun Li
2018 Electrospinning Method Used to Create Functional Nanocomposites Films  
Mei 2 , Xiuqiang Zhang 3 , Tingzhou Lei 3 , Zhen Zhang 1 and Meichun Li 1 *Address all correspondence to: 1 School of Renewable Natural Resources, Louisiana State University, Baton Rouge  ...  … Electrospun Poly(Ethylene Oxide) Fibers Reinforced with Poly (Vinylpyrrolidone) Polymer… Qinglin Wu 1 *, Changtong  ... 
doi:10.5772/intechopen.76392 fatcat:ltx3rcxv25dfrlsrvdorgkq5iq

Different Eye Movement Behaviors Related to Artificial Visual Field Defects–A Pilot Study of Video-Based Perimetry

Changtong Mao, Kentaro Go, Yuichiro Kinoshita, Kenji Kashiwagi, Masahiro Toyoura, Issei Fujishiro, Jianjun Li, Xiaoyang Mao
2021 IEEE Access  
doi:10.1109/access.2021.3080687 fatcat:gcf4c3i7p5fvrnoafc7bsibepe

Fatsia Japonica-Derived Hierarchical Porous Carbon for Supercapacitors With High Energy Density and Long Cycle Life

Huiling Li, Lihua Cao, Feng Wang, Gaigai Duan, Wenhui Xu, Changtong Mei, Guoying Zhang, Kunming Liu, Meng Yang, Shaohua Jiang
2020 Frontiers in Chemistry  
However, the key to the electrochemical performance of SCs lies in the choice and design of electrode materials.  ...  increasing energy demand for power, a new generation of energy devices with advanced, low cost, and sustainable sources have attracted great attention from industry, including supercapacitors (SCs), Li-ion  ... 
doi:10.3389/fchem.2020.00089 pmid:32154215 pmcid:PMC7044675 fatcat:354zhyknjvdmfginegttlliipu

Complex dynamics and coexistence of period-doubling and period-halving bifurcations in an integrated pest management model with nonlinear impulsive control

Changtong Li, Sanyi Tang, Robert A. Cheke
2020 Advances in Difference Equations  
An expectation for optimal integrated pest management is that the instantaneous numbers of natural enemies released should depend on the densities of both pest and natural enemy in the field. For this, a generalised predator–prey model with nonlinear impulsive control tactics is proposed and its dynamics is investigated. The threshold conditions for the global stability of the pest-free periodic solution are obtained based on the Floquet theorem and analytic methods. Also, the sufficient
more » ... ons for permanence are given. Additionally, the problem of finding a nontrivial periodic solution is confirmed by showing the existence of a nontrivial fixed point of the model's stroboscopic map determined by a time snapshot equal to the common impulsive period. In order to address the effects of nonlinear pulse control on the dynamics and success of pest control, a predator–prey model incorporating the Holling type II functional response function as an example is investigated. Finally, numerical simulations show that the proposed model has very complex dynamical behaviour, including period-doubling bifurcation, chaotic solutions, chaos crisis, period-halving bifurcations and periodic windows. Moreover, there exists an interesting phenomenon whereby period-doubling bifurcation and period-halving bifurcation always coexist when nonlinear impulsive controls are adopted, which makes the dynamical behaviour of the model more complicated, resulting in difficulties when designing successful pest control strategies.
doi:10.1186/s13662-020-02971-9 doaj:32854bd133204637820ed01f39ea75ee fatcat:wffikeolcbe3piufuqkqiqm7hy

COP9 Signalosome Subunit 3 Restricts Neuroinflammatory Responses During Cerebral Ischemia/Reperfusion Injury Through Stabilizing Suppressor of Cytokine Signaling 3 Protein

En Liang, Xiaojun Li, Wenjun Fu, Changtong Zhao, Baoying Yang, Zhonghua Yang
2021 Neuropsychiatric Disease and Treatment  
The suppressor of cytokine signaling 3 (SOCS3) is a specific negative regulator of signal transducer and activator of transcription 3 (STAT3) signaling, which is predominantly activated to induce neuroinflammatory response in microglia and functions essential roles during cerebral ischemia-reperfusion (I/R) injury. Constitutive photomorphogenesis 9 (COP9) signalosome (CSN) is a signaling platform controlling protein stability by remodeling of cullin-RING ubiquitin ligases, which is recently
more » ... rted to specifically recognize proteins with SOCS-box domains. However, whether SOCS3 is related to COP9 signalosome in neuroinflammation during cerebral I/R injury is completely unclear. Mice subjected to transient middle cerebral artery occlusion (MCAO) and reperfusion, and BV2 microglia cells treated with oxygen-glucose deprivation and reoxygenation (OGD/R) were used to mimic cerebral I/R injury. Western blot, qRTPCR, immunofluorescence, and co-Immunoprecipitation assays were performed to explore the regulatory mechanism of SOCS3 on neuroinflammation and the relationship of SOCS3 and COP9 signalosome during cerebral I/R injury. SOCS3 expression is significantly upregulated in microglia during OGD/R treatment, and overexpression of SOCS3 suppresses OGD/R-induced STAT3 activation and inflammatory factor expression. Furthermore, we find that COP9 signalosome subunit 3 (CSN3) interacts with SOCS3 protein to enhance its stability, thereby resulting in restricting OGD/R-induced STAT3 activation and inflammatory response. Moreover, we find that knockdown of CSN3 evidently accelerates STAT3 activation, and aggravates cerebral I/R injury in vivo. CSN3 restricts neuroinflammatory responses during cerebral I/R injury through stabilizing SOCS3 protein and indicates that CSN3 a potential therapeutic target for cerebral I/R injury.
doi:10.2147/ndt.s298966 pmid:33911869 pmcid:PMC8075360 fatcat:ptvhbnaxyrhybfg5konnkiylym

Percutaneous Endoscopic Interlaminar Discectomy with Modified Sensation-Motion Separation Anesthesia for Beginning Surgeons in the Treatment of L5-S1 Disc Herniation

Meng Kong, Changtong Gao, Wenbin Cong, Guanghui Li, Chuanli Zhou, Xuexiao Ma
2021 Journal of Pain Research  
To compare the clinical effects of local anesthesia (LA), general anesthesia (GA) and modified sensation-motion separation anesthesia (MA) in percutaneous endoscopic interlaminar discectomy (PEID) in the treatment of L5/S1 lumbar disc herniation (LDH) for the purpose of guiding junior surgeons. Eighty-four patients with L5/S1 LDH underwent PEID using three anesthesia methods. Patients in the LA (26), GA (29) and MA (29) groups received a follow-up examination retrospectively. The general
more » ... ers, preparation and anesthesia duration, operative duration, recovery time, incidence of complications, ambulation time, length of hospital stay, incidence of severe complications, and reoperation rate were compared, and clinical outcomes were analyzed using a visual analog scale (VAS), the Oswestry Disability Index (ODI), and the Short-Form Health Survey 36 (SF-36). MA demonstrated obvious advantages over the other two methods with respect to operative duration and resulted in a better intraoperative experience than LA. The patients in the MA group required less time in bed postoperatively and shorter hospital stays than those in the GA group. The mean postoperative VAS, ODI and SF-36 scores were significantly better than the preoperative scores in all groups (P<0.05), but no significant differences in these scores were found among the three groups (P>0.05). Three cases (3/29) of nervous disorder occurred in the GA group. Two patients (one in the GA group (1/29) and one in the LA (1/26) group) underwent revision surgery, with a total recurrence rate of 2.4% (2/84). Due to its high safety and good tolerance by patients, MA is a suitable method for spinal surgeons who are inexperienced with PEID in the treatment of L5/S1 disc herniation.
doi:10.2147/jpr.s306319 pmid:34267548 pmcid:PMC8275187 fatcat:qo7glbwpjfhvje5yhsid4zcdmq

A Novel Double Perovskite Oxide Semiconductor Sr 2 CoWO 6 as Bifunctional Photocatalyst for Photocatalytic Oxygen and Hydrogen Evolution Reactions from Water under Visible Light Irradiation

Ahmed Mahmoud Idris, Taifeng Liu, Jafar Hussain Shah, Xianwen Zhang, Changtong Ma, Anum Shahid Malik, Ailing Jin, Saadia Rasheed, Yimeng Sun, Can Li, Hongxian Han
2021 Solar RRL  
In the original version of the published article, the scanning electron microscopy images of Sr 2 CoWO 6 (Co/W = 3: 2 and 1: 4 samples in Figure 1D ,E appear to be the same image of one sample from different magnifications and MottÀSchottky plots in Figure 3A -C were not plotted and calculated based on the Y-axis at 0. The corrected MottÀSchottky plots of Figure 3 (A-C) based on the Y-axis at 0 and following band structure analysis are provided herein. These corrections are minor and do not
more » ... r the conclusion of the paper. The authors apologize for any inconvenience or misunderstanding that this error may have caused. After correction, the values of the valence band (VB) and conduction band (CB) of the samples were slightly changed as can be seen in Figure 3D below. Accordingly, the paragraph describing the MottÀSchottky results are corrected as follows: "The flat band potentials (E fb ) of the Sr 2 CoWO 6 (Co/W ¼ 1: 1, 3: 2, and 1: 4) samples were calculated to be ca. 1.1 V, 0.86 V, and 0.63 V vs. NHE at pH ¼ 7, respectively. Generally, it is known that the flat-band potentials of p-type semiconductors are ca. 0.3 V more positive than the VB. With this assumption, the VB positions of the samples with Co/W ¼ 1: 1, 3: 2, and 1: 4 could be estimated to be ca. 1.4 V, 1.16 V, and 0.93 V vs. NHE at pH ¼ 7, respectively. Since the (E g ) of the samples with Co/W of 1: 1, 3: 2, 1: 4 are ca. 1.7 eV, 1.45 eV, and 1.77 eV, and the definition of eV is a unit of energy gained by the charge of a single electron moved across an electric potential difference of one volt (1 eV ¼ 1e 1V, 1e %1.602 10 À19 C), the CB positions of them can be estimated to be ca. À0.3 V, À0.29 V, and À0.84 V vs NHE at pH ¼ 7, respectively." Accordingly, the abstract is corrected as follows: "The sample synthesized with precursor Co/W ratio of 1:4 has CB and VB located at ca. À0.84 and 0.93 eV versus the normal hydrogen electrode (NHE) at pH ¼ 7, respectively." Figure 1. D and E) SEM images of Sr 2 CoWO 6 (Co/W = 3:2 and 1:4, respectively).
doi:10.1002/solr.202000702 fatcat:jqzidxvyanbb7ksiadvkrlyh7u
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