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Although current quality indicators of colonoscopy recommend 6 minutes as the minimum standard for withdrawal time (WT), the impact of a WT longer than 6 minutes on neoplasia detection is unclear. A multicenter randomized controlled trial involving 1027 patients was conducted from January 2018 to July 2019. Participants were randomly divided into a 9-minute (n = 514) and 6-minute (n = 513) WT group, and a timer was used to adjust the withdrawal speed. The primary outcome was the adenoma detection rate (ADR). Intention-to-treat analysis showed a significantly higher ADR in the 9-minute versus 6-minute WT group (36.6% vs. 27.1%, P =.001). Prolonging WT from 6 to 9 minutes significantly increased ADR of the proximal colon (21.4% vs. 11.9%, P <.001) as well as of the less experienced colonoscopists (36.8% vs. 23.5%, P =.001). Improvements were also observed in the polyp detection rate (58.0% vs. 47.8%, P <.001), and mean number of polyps and adenomas detected per colonoscopy (1.1 vs. 0.9, P =.002; 0.5 vs. 0.4, P =.008, respectively). The higher ADRs in 9-minute WT were also confirmed by the per-protocol (PP) analysis and subgroup analyses, with an increased rate of sessile serrated lesion detection in the 9-minute WT by PP analysis (4.0% vs. 1.3%, P =.04). Multivariate logistic regression demonstrated that the 9-minute WT was independently associated with increased ADR (P =.005). Prolonging WT from 6 to 9 minutes significantly improved ADR, especially in the proximal colon and for less experienced colonoscopists. A 9-minute WT benchmark should be considered as one of the quality indicators of colonoscopy. ClinicalTrials.gov (identifier, NCT03399045) [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, we investigate the effect of diffusion on pattern formation in FitzHugh–Nagumo model. Through the linear stability analysis of local equilibrium we obtain the condition how the Turing bifurcation, Hopf bifurcation and the oscillatory instability boundaries arise. By using the method of the weak nonlinear multiple scales analysis and Taylor series expansion, we derive the amplitude equations of the stationary patterns. The analysis of amplitude equations shows the occurrence of different complex phenomena, including Turing instability Eckhaus instability and zigzag instability. In addition, we apply this analysis to FitzHugh–Nagumo model and find that this model has very rich dynamical behaviors, such as spotted, stripe and hexagon patterns. Finally, the numerical simulation shows that the analytical results agree with numerical simulation. [ABSTRACT FROM AUTHOR]

Abstract: By using the bifurcation theory of dynamical systems to modified nonlinear dispersive phi-four equation, we analysis all bifurcations and phase portraits in the parametric space, the existence of solitary wave solutions and uncountably infinite many smooth and non-smooth periodic wave solutions is obtained. Under different parametric conditions, various sufficient conditions to guarantee the existence of the above solutions are given. Some explicit exact solution formulas are acquired for some special cases. [ABSTRACT FROM AUTHOR]

Abstract: A composite nano-crystalline structured thin film was realized by depositing mixed Al2O3 and MgO coating material using physical vapor deposition approach and then annealing at high temperature. The film thus fabricated retains a high transmission even after annealing at 1500°C. The grain size of less than 100nm was measured by atomic force microscopy and the composite nano-crystalline structure of spinel and corundum was confirmed by the X-ray diffraction pattern analysis. Based on this, Bragg grating stacks were fabricated by depositing alternating quarter-wave layers of Al2O3 and Al2O3/MgO at the end of a sapphire crystal fiber at first and then the layers of NiO and Al2O3/MgO on the surface of a sapphire slice. The performance of the grating stacks at high temperature or after high temperature annealing was measured. It was found that the reflection peak measured from the grating stacks can survive a high temperature up to 1050°C but will disappear after annealing at temperature of 1100°C or above. A conclusion of inter-diffusion between layers of stack was obtained to explain the phenomenon of reflection peak disappearing after annealing at high temperature. [Copyright &y& Elsevier]

Abstract: In this paper, shock wave solutions of the compound Burgers–KdV equation is studied by using qualitative theory of differential equation and ansatz method. The existence and uniqueness of different types of travelling waves of the system are obtained by analyzing qualitatively the existence and uniqueness of the heteroclinic trajectories of the ordinary differential equation. We construct some travelling wave solutions and indicate their stability and bifurcation. [Copyright &y& Elsevier]

Abstract: By using bifurcation method of phase portraits and theory of dynamical systems to the nonlinear Klein–Gordon model, in the range , numbers of kink compactons, solitary wave, kink and anti-kink waves are given for each parameter condition. The parameter condition when the type of travelling wave changes is obtained. [Copyright &y& Elsevier]

Abstract: The dynamical behavior and special exact solutions of the generalized Degasperis–Procesi equation u t + c 0 u x − u txx + auu x =3u x u xx + uu xxx is analyzed by using bifurcation theory and the method of phase portraits analysis. As a result, the analytic expressions of peakon solutions, compacton solutions and periodic cusp wave solutions are obtained. And the condition under which peakon and compacton solutions appear are also given. In the meantime, the reason that solitary cusp wave and periodic cusp wave appear is given. [Copyright &y& Elsevier]

Abstract: By using bifurcation method to Whitham–Broer–Kaup shallow water equations, bifurcation parameter sets are shown. Numbers of solitary waves, kink waves and periodic waves are given. Under various parameter conditions, all explicit formulas of solitary wave solutions, kink wave solutions and periodic wave solutions are listed. [Copyright &y& Elsevier]

Abstract: By using the theory of bifucations of dynamical systems to a model of the Hydrogen-bonded systems, the existence of solitary wave, kink and anti-kink wave solutions and uncountably infinite many smooth and non-smooth periodic wave solutions is obtained. Under different parametric conditions, various sufficient conditions to guarantee the existence of the above solutions are given. In some simple parametric conditions, exact explicit and implicit solution formulas are listed. [Copyright &y& Elsevier]

By using the bifurcation theory of dynamical systems to the generalized Hirota–Satsuma coupled KdV system, bifurcation parameter sets are shown. Numbers of solitary waves, kink waves and periodic waves are given. Under various parameter conditions, all explicit formulas of solitary wave solutions and kink wave solutions and periodic wave solutions are listed. [Copyright &y& Elsevier]

• The approximate range of eigenvalue of the network matrix is shown. • The instability condition about diffusion and the connection probability in the network-organized system are derived. • The estimated range of connection probability is also deduced. • Mechanism of spiking of the neuron can be explained by using diffusion network and matrix theory. Although there is general agreement that the network plays an essential role in the biological system, how the connection probability of network affects the natural model(Especially neural network) is poorly understood. In this paper, we show the impact of the network on Turing instability in the FitzHugh-Nagumo(FN) model. Then we obtain the condition of how the Turing bifurcation, saddle-node bifurcation, and Turing instability occur. By using the Gershgorin circle theorem, we investigate the relationship between degree and eigenvalue of the network matrix, and obtain the approximate range of eigenvalue of the network matrix. Also, We derive the instability condition about diffusion and the connection probability in the network-organized system. And then we obtain the estimated range of connection probability. Meanwhile we apply these results to explaining the spiking of neuron and find this system has rich dynamics behavior. Finally, the numerical simulation verifies our analytical results. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we investigate the dynamical behavior of traveling wave solutions in the Zhiber–Shabat equation by using the bifurcation theory and the method of phase portraits analysis. As a result, we obtain the conditions under which smooth and non-smooth traveling wave solutions exist, and give some exact explicit solutions for some special cases. [Copyright &y& Elsevier]

Abstract: A new proaporphine alkaloid, 8, 9-dihydroprooxocryptochine (1), together with three known alkaloids, was isolated from the aerial parts of Meconopsis horridula Hook. f. & Thomson (Papaveraceae), a traditional Tibetan medicine. The structure of 1 was determined by spectroscopic methods. [Copyright &y& Elsevier]

Abstract This paper is concerned with the problem of pinning synchronization for memristive neural networks with time-varying delays via aperiodic intermittent control. By applying aperiodic intermittent control to partial nodes of the memristive neural networks, some new general criteria for global exponential synchronization are derived based on the theory of nonsmooth analysis. The obtained results indicate that it is the control rates rather than the control periods or control widths are involved in the synchronization criteria. In addition, a feasible region of the control gains and control rates is established for achieving global exponential synchronization. Finally, numerical simulations are given to verify the correctness of our theoretical analysis. [ABSTRACT FROM AUTHOR]

Gentiana straminea is a popular Tibetan medicine that has been used for thousands of years in China to treat various diseases and conditions. Although it has multiple pharmaceutical purposes and important economic plant resource in China, transcriptome and molecular base still known limited. In flowering season, samples were collected from different tissues, using the NGS Illumina. Solexa platform, about 58.85 million sequencing reads were generated and assembled de novo, yielding 78,764 high quality unigenes with an average length of 1090 bp. Gene Ontology (GO), KEGG pathway mapping showed that 49,033 of these were identified as putative homologs of annotated sequences in the protein databases. Among them, candidate genes associated with iridoid, flavonoid and anthocyanin were identified. Further the key enzymes involved to iridoid and flavonoid synthesis pathway were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) on different tissues, the flower and root had the higher expression than leaves. In addition, 7591 SSR markers were identified from the unigenes of the G . straminea transcriptome. The foundation of G . straminea provided the important resource for facilitating to study molecular and functional genomics of it and related this species on the Qinghai–Tibet Plateau. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, explicit and exact travelling wave solutions of B(m, n) equations are investigated by using a generalized algebraic method. A series of explicit exact solutions, such as solitary wave, triangular periodic, rational, Jacobi and Weierstrass elliptic function periodic solutions are obtained. Many new results are presented. [Copyright &y& Elsevier]

Abstract: By using the theory of bifurcations of dynamical systems to a class of the generalized Benjamin–Bona–Mahony (GBBM) equation, the existence of solitary wave solutions and uncountably infinite, many smooth and non-smooth periodic wave solutions are obtained. It can be shown that the existence of singular curves in a traveling wave system is the reason why smooth waves converge to cusp waves, finally. When parameters are varied, under different parametric conditions, various sufficient conditions to guarantee the existence of the above solutions are given. [Copyright &y& Elsevier]