DISTURBANCE ATTENUATION FOR A CLASS OF DISCRETE-TIME SWITCHED SYSTEMS WITH EXPONENTIAL UNCERTAINTY

Changlin Li,Fei Long,Guohui Ren 대한수학회 2011 대한수학회지 Vol.48 No.4

The disturbance attenuation problem for a class of discrete-time switched linear systems with exponential uncertainties via switched state feedback and switched dynamic output feedback is investigated, respectively. By using Taylor series approximation and convex polytope technique, exponentially uncertain discrete-time switched linear system is transformed into an equivalent switched polytopic model with additive norm bounded uncertainty. For such equivalent switched model, one designs its switching strategy and associated state feedback controllers and dynamic output feedback controllers so that whole switched model is asymptotical stabilization with H-infinity disturbance attenuation based on switched Lyapunov function and LMI approach. Finally, two numerical examples are presented to illustrate our results.

DISTURBANCE ATTENUATION FOR A CLASS OF DISCRETE-TIME SWITCHED SYSTEMS WITH EXPONENTIAL UNCERTAINTY

Li, Changlin,Long, Fei,Ren, Guohui Korean Mathematical Society 2011 대한수학회지 Vol.48 No.4

The disturbance attenuation problem for a class of discretetime switched linear systems with exponential uncertainties via switched state feedback and switched dynamic output feedback is investigated, respectively. By using Taylor series approximation and convex polytope technique, exponentially uncertain discrete-time switched linear system is transformed into an equivalent switched polytopic model with additive norm bounded uncertainty. For such equivalent switched model, one designs its switching strategy and associated state feedback controllers and dynamic output feedback controllers so that whole switched model is asymptotical stabilization with H-in nity disturbance attenuation base on switched Lyapunov function and LMI approach. Finally, two numerical examples are presented to illustrate our results.

Transcriptome analysis of gene expression patterns during embryonic development in golden cuttlefish (Sepia esculenta)

Li Bian,Changlin Liu,Siqing Chen,Fazhen Zhao,Jianlong Ge,Jie Tan 한국유전학회 2018 Genes & Genomics Vol.40 No.3

Golden cuttlefish (Sepia esculenta) is an important economic species in China. Because of the rapid decline of its natural resource, researchers are exploring breeding technique for this species. The major obstacle that hinders artificial breeding of S. esculenta is the low larvae survival rate. Mortality is especially high during the mouth-opening stage. Investigating the embryogenesis before the first feed could provide theoretical guidance for reproduction control and breeding of S. esculenta and other Sepia species. In this study, we analyzed the dynamics of the S. esculenta transcriptome along different stages of embryonic development by mRNA-sEq. Our bioinformatics protocol identified 1492 differentially expressed genes (DEGs) across the early developmental stages. Gene ontology enrichment analysis showed that the DEGs were significantly involved in developmental processes and molecular functions, including chitin metabolic process, peptidase activity, catalytic activity, and calcium ion binding. Our results indicated that genes related to cuttlebone development and gene regulation functions were active during the early life phase of S. esculenta. Hierarchical clustering of the DEGs reflected the successiveness of the developmental stages, revealing that gene expression patterns of neighboring stages were similar. The DEG analysis allowed us to identify specific genes and relevant biological pathways to better understand the molecular mechanisms during each developmental stage. This study provides novel insights into the processes underlying the early developmental stages of S. esculenta. The transcriptomic data and identified genes will serve as valuable references for the developmental biology of this species and will help promote its aquaculture research.

A Novel Approach to Synthesize Nitrogen-Deficient g-C3N4 for the Enhanced Photocatalytic Contaminant Degradation and Electrocatalytic Hydrogen Evolution

Xiaoxiao Li,Kailian Zhang,Man Zhou,Kai Yang,Shi Yang,Xiaoshuai Ma,Changlin Yu,Yu Xie,Weiya Huang,Qizhe Fan 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2020 NANO Vol.15 No.02

Graphitic carbon nitride with nitrogen vacancies was successfully synthesized by the three-step method for the calcination of melamine, following urea-assisted hydrothermal and jacjoin calcination approach. The structural, surface, optical and electric properties were characterized by XRD, FT-IR, SEM, TEM, UV–Vis DRS, PL, N2 physical adsorption/desorption and electrochemical methods, which proved that this strategy of modifying g-C3N4 by nitrogen vacancies not only increased the specific surface area, exposed more active sites, but also inhibited the recombination of photogenerated carriers on the surface of photocatalysts, resulting in the enhancement of photocatalytic and electrocatalytic performances. The photocatalytic activities were measured under visible light irradiation ( λ > 420 nm), and their degradation efficiencies could be achieved for 99.8%, 55%, 100% and 99.7% corresponding to that of rhodamine B, acid orange II, methyl orange and methylene blue, respectively. The trapping experiments demonstrated that ·O2- played an important role in the degradation process. In addition, being an active electrocatalyst, nitrogen-deficient g-C3N4 showed a lower Tafel slope, smaller overpotential and the more effective electrochemical surface area compared with that of bare g-C3N4 in neutral media. This work underlines the importance of defect engineering to promote catalytic performance, which can provide a simple and efficient way for modifying g-C3N4 and other N-based catalysts.

The antimicrobial activity of Cbf-K16 against MRSA was enhanced by β-lactamantibiotics through cell wall non-integrity

Bo Li,Wei Kang,Hanhan Liu,Yanrong Wang,Changzhong Yu,Xinyi Zhu,Jie Dou,Haibo Cai,Changlin Zhou 대한약학회 2016 Archives of Pharmacal Research Vol.39 No.7

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as one of the most important pathogens both in health care and in community-onset infections. Cbf-K16, a cathelicidin-like antimicrobial peptide, presented broad antimicrobial activity during our previous studies. We evaluated the potential for synergy of Cbf-K16 with ceftazidime/ampicilin against MRSA, which was resistant to these two antibiotics with the minimum inhibitory concentration more than 64 μg/ml. The combinations showed a synergistic effect by a checkerboard assay with a fractional inhibitory concentration index ≤0.5. The killing curves of the combination treatment against MRSA showed that CFU counts decreased rapidly within 4 h by almost five logs, while single medication groups and the control group exhibited little inhibitory effect. In addition, in a mice bacteremia model, studies indicated that the combination treatment significantly prolonged the survival time of mice infected with MRSA, with a death protection rate of 80 %. Flow cytometry analysis and transmission electron microscopy indicated that combination- treated MRSA was completely ruptured with the cellular contents leaked out. The synergistic effect showed that Cbf-K16 selectively killed cells with non-integrity induced by cell wall inhibition antibiotics, suggesting that Cbf-K16 is a potential therapeutic agent and adjuvant for antimicrobial chemotherapy.

BF-30 effectively inhibits ciprofloxacin-resistant bacteria in vitro and in a rat model of vaginosis

Wang, Jing,Li, Bing,Li, Yang,Dou, Jie,Hao, Qingru,Tian, Yuwei,Wang, Hui,Zhou, Changlin 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.7

Bacterial infections are becoming increasingly difficult to treat due to the increasing number of multidrug-resistant strains. Cathelicidin-BF (BF-30) is a cathelicidin-like antimicrobial peptide and exhibits broad antimicrobial activity against bacteria. In the present study, the antibacterial activity of BF-30 against ciprofloxacin-resistant Escherichia coli and Staphylococcus aureus was examined, and the protective effects of this peptide against these bacteria in rats with bacterial vaginosis were identified for the first time. The data showed that BF-30 had effective antimicrobial activities against ciprofloxacin-resistant E. coli and S. aureus. The minimal inhibitory concentrations for both bacterial strains were $16{\mu}g/ml$, and the minimal bactericidal concentrations were 64 and $128{\mu}g/ml$, respectively. A time course experiment showed that the CFU counts rapidly decreased after BF-30 treatment, and the bacteria were nearly eliminated within 4 h. BF-30 could reduce the fold change (CFU/ml) in local colonization by drug-resistant E. coli and S. aureus to 0.01 at a dose of 0.8 mg/kg/day in the rats' vaginal secretions. In addition, BF-30 induced membrane permeabilization and bound to the genomic DNA, interrupting protein synthesis. Taken together, our data demonstrate that BF-30 has potential therapeutic value for the prevention and treatment of bacterial vaginosis.

A Three-way Handshaking Access Mechanism for Point to Multipoint In-band Full-duplex Wireless Networks

( Haiwei Zuo ),( Yanjing Sun ),( Changlin Lin ),( Song Li ),( Hongli Xu ),( Zefu Tan ),( Yanfen Wang ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.7

In-band Full-duplex (IBFD) wireless communication allows improved throughput for wireless networks. The current Half-duplex (HD) medium access mechanism Request to Send/Clear to Send (RTS/CTS) has been directly applied to IBFD wireless networks. However, this is only able to support a symmetric dual link, and does not provide the full advantages of IBFD. To increase network throughput in a superior way to the HD mechanism, a novel three-way handshaking access mechanism RTS/SRTS (Second Request to Send)/CTS is proposed for point to multipoint (PMP) IBFD wireless networks, which can support both symmetric dual link and asymmetric dual link communication. In this approach, IBFD wireless communication only requires one channel access for two-way simultaneous packet transmissions. We first describe the RTS/SRTS/CTS mechanism and the symmetric/asymmetric dual link transmission procedure and then provide a theoretical analysis of network throughput and delay using a Markov model. Using simulations, we demonstrate that the RTS/SRTS/CTS access mechanism shows improved performance relative to that of the RTS/CTS HD access mechanism.

Characterization of the global transcriptome and microsatellite marker information for spotted halibut Verasper variegatus

Jianlong Ge,Siqing Chen,Changlin Liu,Li Bian,Huiling Sun,Jie Tan 한국유전학회 2017 Genes & Genomics Vol.39 No.3

The spotted halibut Verasper variegatus is an economically important flatfish species distributed in Japan, Korea and China. However, the genomic resources regarding this species were scarcity, which hindered our understanding of the genetics and biological mechanisms in spotted halibut. In this study, we examined the global transcriptome from six major tissues of spotted halibut. Approximately 40 million of high quality reads were generated using Illumina paired-end sequencing technology. More than 9 Gbp data were generated, and de novo assembled into 59,235 unigenes, with an N50 of 938 bp. Based on sequence similarity search with known protein database, 34,084 (57.5%) showed significant similarity to known proteins in Nr database, and 28,875 (48.7%) had BLAST hits in Swiss-Prot database. 19,562 and 23,037 unigenes were assigned into gene ontology categories and clusters of orthologous group, respectively. 9138 unigenes were mapped to 211 KEGG pathways. For functional marker development, 13,322 candidate simple sequence repeats were identified in the transcriptome and 7235 primer pairs were successfully designed. Among 72 primer pairs selected for validation, 67 (93.1%) were successful in PCR amplification and 14 (19.4%) exhibited obvious repeat length polymorphisms in a culture spotted halibut population. The transcriptomic data and microsatellite markers will provide valuable resources for future functional gene analyses, genetic map construction, and quantitative trait loci mapping in V. variegatus.

BF-30 effectively inhibits ciprofloxacin-resistant bacteria in vitro and in a rat model of vaginosis

Jing Wang,Bing Li,Yang Li,Jie Dou,Qingru Hao,Yuwei Tian,Hui Wang,Changlin Zhou 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.7

Bacterial infections are becoming increasinglydifficult to treat due to the increasing number of multidrugresistantstrains. Cathelicidin-BF (BF-30) is a cathelicidinlikeantimicrobial peptide and exhibits broad antimicrobialactivity against bacteria. In the present study, the antibacterialactivity of BF-30 against ciprofloxacin-resistantEscherichia coli and Staphylococcus aureus was examined,and the protective effects of this peptide against these bacteriain rats with bacterial vaginosis were identified for thefirst time. The data showed that BF-30 had effective antimicrobialactivities against ciprofloxacin-resistant E. coliand S. aureus. The minimal inhibitory concentrations forboth bacterial strains were 16 lg/ml, and the minimal bactericidalconcentrations were 64 and 128 lg/ml, respectively. A time course experiment showed that the CFUcounts rapidly decreased after BF-30 treatment, and thebacteria were nearly eliminated within 4 h. BF-30 couldreduce the fold change (CFU/ml) in local colonization bydrug-resistant E. coli and S. aureus to 0.01 at a dose of0.8 mg/kg/day in the rats’ vaginal secretions. In addition,BF-30 induced membrane permeabilization and bound to thegenomic DNA, interrupting protein synthesis. Taken together,our data demonstrate that BF-30 has potential therapeuticvalue for the prevention and treatment of bacterialvaginosis.

A Study on Construction and Simulation of Agricultural Machinery System Control Model

Wang Ying,Xu Shiyang,Liu Shiqiang,Li Xiaoxue,Ao Changlin 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.8

In order to study the state-changing and running rules of agricultural machinery system, this paper establishes the control model of agricultural machinery system under the discrete-state space based on control theory, from the perspective of the complex systems and with reference to the actual conditions of agricultural production; conducts the qualitative analysis on the system model, builds the relevant simulation model of agricultural machinery system accordingly, and verifies the running of the simulation model. This control model can provide effective basis and reference for further quantitative studies on state evolution of agricultural machinery system.