Microbial Communities in Semi-consolidated Carbonate Sediments of the Southwest Indian Ridge

Jiwei Li,Xiaotong Peng,Huaiyang Zhou,Jiangtao Li,Zhilei Sun,Shun Chen 한국미생물학회 2014 The journal of microbiology Vol.52 No.2

White semi-consolidated carbonate sediments attached toblack ferromanganese oxide films were collected approximately50 km west of a newly discovered hydrothermal fieldnear the Southwest Indian Ridge (SWIR). The biodiversity ofthe prokaryotic communities within the field was examinedusing clone library-based culture-independent analysis ofthe exterior black oxides and the interior white carbonates. Subsequent 16S rRNA gene analysis suggested that Gammaproteobacteria,Acidobacteria, and Thaumarchaeota membersdominated the bacterial and archaeal clone libraries. To further characterize the metabolic processes within themicrobial community, analyses of the amoA (coding the alphasubunit of the ammonia monooxygenase for Archaea)and aprA (coding the alpha subunit of the dissimilatory adenosine-5 -phosphosulfate reductase for the sulfate-reducingand sulfur-oxidizing prokaryotes) functional genes wereconducted. The functional gene analysis results suggestedthat Thaumarchaeota and Alphaproteobacteria memberswere the potential players that participated in N and S cyclesin this marine carbonate sedimentary environment. Thispaper is the first to describe the microbial communities andtheir potential metabolic pathways within the semi-consolidatedcarbonate sediments of the SWIR.

Silencing of Long Non-Coding RNA MALAT1 Promotes Apoptosis of Glioma Cells

Jianping Xiang,Shifeng Guo,Shuling Jiang,Yuelong Xu,Jiwei Li,Li Li,Jinyu Xiang 대한의학회 2016 Journal of Korean medical science Vol.31 No.5

The metastasis-associated lung adenocarcinoma transcription 1 (MALAT1) is a highly conserved long non-coding RNA (lncRNA) gene. However, little is known about the pathological role of lncRNA MALAT1 in glioma. In the present study, we explored the expression level of lncRNA MALAT1 in primary glioma tissues as well as in U87 and U251 glioma cell lines. Using qRT-PCR, we found that the expression of lncRNA MALAT1 was significantly increased in glioma tissues compared with that of paracancerous tissues. Meanwhile, the expression of MALAT1 was highly expressed in U98 and U251 cells. In order to explore the function of MALAT1, the expression of MALAT1 was greatly reduced in U87 and U251 cells transfected with siRNA specifically targeting MALAT1. Consequently, cell viability of U87 and U251 cells were drastically decreased after the knockdown of MALAT1. Concomitantly, the apoptosis rate of the two cell lines was dramatically increased. Furthermore, the expression levels of some tumor markers were reduced after the knockdown of MALAT1, such as CCND1 and MYC. In summary, the current study indicated a promoting role of MALAT1 in the development of glioma cell.

Switching Predictive Control for Continuous-time Markovian Jump Delay Systems

Jiwei Wen,Li Peng 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.3

This paper is concerned with switching model predictive control (SMPC) for continuous-time Markovianjump delay systems (MJDSs). First, a piecewise constant switching predictive controller, which only depends onthe average dwell time (ADT) switching laws rather than the jumping modes, is obtained by employing the ADTapproach under the infinite-time predictive control design framework . Such a control strategy is proposed to make atrade-off between robustness and adaptivity when the design complexity of mode-independent and mode-dependentMPC is considered. It is revealed that the SMPC can deal with MJDSs with both time varying and time invariantjump rates and cover the mode-independent MPC as a special cease. Second, the feasibility of the SMPC schemeand the mean square stability of the closed-loop MJDS are discussed by using the stochastic invariance of theellipsoid set over each sampling period. A numerical example is given to illustrate the main results.

Segregation Ratio in Selfed and Crossed Progenies Demonstrates Single Dominant Gene Inheritance of Day-neutrality in Strawberry

Jiwei Ruan,용영록,Chunmei Yang,Guoxian Wang,Lifang Wu,Shenchong Li,Pang Tao,Chengfei Liao,Ji-Hua Wang 한국원예학회 2017 Horticulture, Environment, and Biotechnology Vol.58 No.6

Studies on the inheritance of day-neutrality, a highly desirable trait in strawberry (Fragaria×ananassa),have not been conclusive because flowering phenotypes were evaluated based on different materials and experimentalsites. In the present study, selfed and crossed progenies of Day-neutral (DN) ‘Albion’ and June-bearing (JB) ‘Akihime’cultivars, namely ‘Albion’ × ‘Albion’, ‘Akihime’ × ‘Akihime’, and ‘Akihime’ × ‘Albion’, were established in 2013and 2014. The flowering phenotype (DN or JB) of seedlings from each of the three progenies, as well as of parentalplants, was evaluated for two successive years (2015 and 2016) in Central Yunnan, China, and their segregationratios were used to elucidate day-neutrality inheritance. Single dominant gene inheritance was demonstrated forday-neutrality, although minor genes (from the JB parent ‘Akihime’) likely increase DN magnitude. During thejuvenile stage (i.e., long before the first inflorescence), the major gene controlling day-neutrality may not beexpressed. We provide basic information for DN gene mapping and cloning, as well as materials (progenies) fordomestic DN strawberry breeding.

Blast vibration of a large-span high-speed railway tunnel based on microseismic monitoring

Li, Ao,Fang, Qian,Zhang, Dingli,Luo, Jiwei,Hong, Xuefei Techno-Press 2018 Smart Structures and Systems, An International Jou Vol.21 No.5

Ground vibration is one of the most undesirable effects induced by blast operation in mountain tunnels, which could cause negative impacts on the residents living nearby and adjacent structures. The ground vibration effects can be well represented by peak particle velocity (PPV) and corner frequency ($f_c$) on the ground. In this research, the PPV and the corner frequency of the mountain surface above the large-span tunnel of the new Badaling tunnel are observed by using the microseismic monitoring technique. A total of 53 sets of monitoring results caused by the blast inside tunnel are recorded. It is found that the measured values of PPV are lower than the allowable value. The measured values of corner frequency are greater than the natural frequencies of the Great Wall, which will not produce resonant vibration of the Great Wall. The vibration effects of associated parameters on the PPV and corner frequency which include blast charge, rock mass condition, and distance from the blast point to mountain surface, are studied by regression analysis. Empirical formulas are proposed to predict the PPV and the corner frequency of the Great Wall and surface structures due to blast, which can be used to determine the suitable blast charge inside the tunnel.

Finite-time Control for Discrete-time Markovian Jump Systems with Deterministic Switching and Time-delay

Jiwei Wen,Li Peng,Sing Kiong Nguang 제어·로봇·시스템학회 2014 International Journal of Control, Automation, and Vol.12 No.3

In this paper, the finite-time control problem is investigated for a class of discrete-time Markovian jump systems (MJLSs) with deterministic switching and time-delay. The considered systems are subject to a piecewise-constant transition probability (TP) matrix, which leads to both the deterministic switches and stochastic jumps. First, the stochastic finite-time boundedness (SFTB) and l2 gain analysis for the systems are studied by employing the average dwell time (ADT) approach. Note that a finite-time weighted l2 gain is obtained to measure the disturbance attenuation level. Then, the mode-dependent and variation-dependent controller is designed such that the resulting closed-loop systems are stochastically finite-time bounded and have a guaranteed disturbance attenuation level. Finally, a numerical example is given to verify the potential of the developed results.

Dielectric and piezoelectric properties of the Ba0.92Ca0.08Ti0.95Zr0.05O3 thin films grown on different substrate

Wei Li,Jigong Hao,Huarong Zeng,Jiwei Zhai 한국물리학회 2013 Current Applied Physics Vol.13 No.7

Lead free Ba0.92Ca0.08Ti0.95Zr0.05O3 (BCZT) thin films were deposited on Pt/Ti/SiO2/Si and LaNiO3(LNO)/Pt/Ti/SiO2/Si substrates by a solegel processing technique, respectively. The effects of substrate on structure,dielectric and piezoelectric properties were investigated in detail. The BCZT thin films deposited on LNO/Pt/Ti/SiO2/Si substrates exhibit (100) orientation, larger grain size and higher dielectric tunability (64%). The BCZT thin films deposited on Pt/Ti/SiO2/Si exhibit (110) orientation, higher Curie temperature (75 ℃),better piezoelectric property (d33 of 50 pm/V) and lower dielectric loss (0.02). The differences in dielectric and piezoelectric properties in the two kinds of oriented BCZT films should be attributed to the difference of structure, in-plane stress and polarization rotation in orientation engineered BCZT films.

Study of temperature-induced structural evolution in (Na0.5Bi0.5)TiO3- (K0.5Bi0.5)TiO3-(K0.5Na0.5)NbO3 lead-free ceramics

Xing Liu,Jiwei Zhai,Bo Shen,Feng Li,Yang Zhang,Peng Li,Baihui Liu 한국물리학회 2017 Current Applied Physics Vol.17 No.5

In this work, the temperature-induced structural evolution in 0.79(Na0.5Bi0.5)TiO3-0.2(K0.5Bi0.5)TiO3- 0.01(K0.5Na0.5)NbO3 (NKBNT) lead-free ceramics was investigated by Raman microscopic spectroscopy combined with electrical macroscopic measurements. The NKBNT ceramics possess the local structure with the coexisted rhombohedral R3c and tetragonal P4bm polar-nano-regions (PNRs). The R3c and P4bm PNRs coexist in a wide temperature range, then the local structure transforms to the P4bm PNRs around the temperature of dielectric maximum (Tm) evidenced by the doublet splitting of Ti-O modes (peak B) and oxygen octahedral vibrational modes (peak C). The discontinuous changes of wavenumber and linewidth of peak B2 and peak C3 as well as the dielectric local maxima around the rhombohedral-tetragonal phase transition temperature (TRT) are considered to result from the thermal evolution of R3c and P4bm PNRs. The macroscopic changes of non-polar phase with electric field and temperature were investigated by the temperature-dependent polarization-electric field (P-E) loops, current-electric field (I-E) loops and bipolar strain (S-E) curves. The electric-field level necessary to form the long-range ferroelectric order from non-polar phase associated with the stability of the induced ferroelectric phase depends strongly on the temperature.

Robust H∞ Filtering for Average Dwell Time Switching Systems via a Nonmonotonic Function Approach

Yun Xie,Jiwei Wen,Li Peng 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.3

To improve the H∞ filtering performance, a non-monotonic Lyapunov function approach with N-stepahead predictive horizon is developed to design a robust H∞ filter for a discrete-time uncertain switched system. With increasing of the number N, filtering performance can be improved as well as the capability of disturbanceattenuation. However, the average dwell time (ADT) constraint of the switching law should be more critical as acost at the same time. To further relax the restriction on the switching law, the mode-dependent ADT switching isintroduced to reduce the ADT bound such that a trade-off between the switching frequency and filtering performancecan be achieved. Therefore, a co-design of the filter and switching law can be obtained by the developed approach.

Stochastic Bounded Consensus Tracking of Second-Order Multi-Agent Systems with Measurement Noises based on Sampled-Data with Small Sampling Delay

Zhihai Wu,Li Peng,Linbo Xie,Jiwei Wen 제어·로봇·시스템학회 2014 International Journal of Control, Automation, and Vol.12 No.1

This paper is devoted to the stochastic bounded consensus tracking problems of second-order multi-agent systems, where the control input of each agent can only use the information measured at the sampling instants from its neighbors or the virtual leader with a time-varying reference state, the measurements are corrupted by random noises, and the signal sampling process induces the small sampling delay. The augmented matrix method, the probability limit theory and some other techniques are employed to derive the necessary and sufficient conditions guaranteeing the mean square bounded consensus tracking. We show that the convergence of the proposed protocol simultaneously depends on the constant feedback gains, the network topology, the sampled period and the sampling delay, and that the static consensus tracking error depends on not only the above mentioned factors, but also the noise intensity and the upper bound of the velocity and the acceleration of the virtual leader. The obtained results cover no sampling delay as its one special case. Simulations are provided to demonstrate the effectiveness of the theoretical results.