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In astronomical observations, the radio frequency interference (RFI) will cause pseudo spectra and reduce the reliability and validity of observational data. The RFI mitigation, which includes many technical innovations of devices and the method studies of data processing, aims at reducing the influence of RFI on the radio astronomical observation. Various efforts were made to improve the anti-RFI capability of the multi-beam receiver (Superconducting Spectroscopic Array Receiver, SSAR) of the Delingha 13.7 m telescope. The interference transmission path was analyzed. The concepts of the device RFI direct coupling coefficient and the device RFI system coupling coefficient were proposed. The proportions of interference introduced in the receiver system by the different devices were quantified, and the interference-susceptible devices in the system were located. After the anti-RFI treatment of the interference-susceptible devices, the anti-RFI capability of the receiver system is improved by 30 dB in average, and the astronomical observation efficiency of the telescope is increased by more than 10%. [ABSTRACT FROM AUTHOR]

Background and aims: The aim of this study is to estimate the longitudinal associations between online social networking addiction (OSNA) and depression, whether OSNA predicts development of depression, and reversely, whether depression predicts development of OSNA. Methods: A total of 5,365 students from nine secondary schools in Guangzhou, Southern China were surveyed at baseline in March 2014, and followed up 9 months later. Level of OSNA and depression were measured using the validated OSNA scale and CES-D, respectively. Multilevel logistic regression models were applied to estimate the longitudinal associations between OSNA and depression. Results: Adolescents who were depressed but free of OSNA at baseline had 1.48 times more likely to develop OSNA at follow-up compared with those non-depressed at baseline [adjusted OR (AOR): 1.48, 95% confidence interval (CI): 1.14-1.93]. In addition, compared with those who were not depressed during the follow-up period, adolescents who were persistently depressed or emerging depressed during the follow-up period had increased risk of developing OSNA at follow-up (AOR: 3.45, 95% CI: 2.51-4.75 for persistent depression; AOR: 4.47, 95% CI: 3.33-5.99 for emerging depression). Reversely, among those without depression at baseline, adolescents who were classified as persistent OSNA or emerging OSNA had higher risk of developing depression compared with those who were no OSNA (AOR: 1.65, 95% CI: 1.01-2.69 for persistent OSNA; AOR: 4.29; 95% CI: 3.17-5.81 for emerging OSNA). Conclusion: The findings indicate a bidirectional association between OSNA and depression, meaning that addictive online social networking use is accompanied by increased level of depressive symptoms. [ABSTRACT FROM AUTHOR]

Background and aims: This study aims to examine the mediating effects of insomnia on the associations between problematic Internet use, including Internet addiction (IA) and online social networking addiction (OSNA), and depression among adolescents. Methods: A total of 1,015 secondary school students from Guangzhou in China participated in a cross-sectional survey. Levels of depression, insomnia, IA, and OSNA were assessed using the Center for Epidemiological Studies-Depression Scale, Pittsburgh Sleep Quality Index, Young's Diagnostic Questionnaire, and Online Social Networking Addiction Scale, respectively. Logistic regression models were fit to test the associations between IA, OSNA, insomnia, and depression. The mediation effects of insomnia were tested using Baron and Kenny's strategy. Results: The prevalence of depression at moderate level or above (CES-D = 21), insomnia, IA, and OSNA were 23.5%, 37.2%, 8.1%, and 25.5%, respectively. IA and OSNA were significantly associated with depression (IA: AOR = 2.79, 95% CI: 1.71, 4.55; OSNA: AOR = 3.27, 95% CI: 2.33, 4.59) and insomnia (IA: AOR = 2.83, 95% CI: 1.72, 4.65; OSNA: AOR = 2.19, 95% CI: 1.61, 2.96), after adjusting for significant background factors. Furthermore, insomnia partially mediated 60.6% of the effect of IA on depression (Sobel Z = 3.562, p < .002) and 44.8% of the effect of OSNA on depression (Sobel Z = 3.919, p < .001), respectively. Discussion: The high prevalence of IA and OSNA may be associated with increased risk of developing depression among adolescents, both through direct and indirect effects (via insomnia). Findings from this study indicated that it may be effective to develop and implement interventions that jointly consider the problematic Internet use, insomnia, and depression. [ABSTRACT FROM AUTHOR]

Dynamical analysis has revealed that, for some nonlinear wave equations, loop- and inverted loop-soliton solutions are actually visual artifacts. The so-called loopsoliton solution consists of three solutions, and is not a real solution. This paper answers the question as to whether or not nonlinear wave equations exist for which a “real” loop-solution exists, and if so, what are the precise parametric representations of these loop traveling wave solutions. [ABSTRACT FROM AUTHOR]

By using the method of planar dynamical systems, we solve exactly a nonlinear Schrödinger (NLS) equation discussed by Khare and Saxena [J. Math. Phys. 56, 032104 (2015)], and give the exact explicit parametric representations of all the traveling wave solutions. [ABSTRACT FROM AUTHOR]

In this paper, a hyperchaotic RTD-based cellular neural network is proposed and its hyperchaotic dynamics is demonstrated. The Lyapunov exponents spectrum is presented, and some typical Lyapunov exponents are calculated in a range of parameters. Several important phase portraits are presented as well. [ABSTRACT FROM AUTHOR]

By using the dynamical system method to study the 2D-generalized Benney-Luke equation, the existence of kink wave solutions and uncountably infinite many smooth periodic wave solutions is shown. Explicit exact parametric representations for solutions of kink wave, periodic wave and unbounded traveling wave are obtained. [ABSTRACT FROM AUTHOR]

This paper considers the problems of determining center or focus and isochronous centers for the planar quasi-analytic systems. Two recursive formulas to determine the focal values and period constants are given. The convergence of first integral near the center is proved. Using the general results to quasi-quadratic systems, the problem of the isochronous center of the origin is completely solved. [ABSTRACT FROM AUTHOR]

By using the method of dynamical systems to the two-component generalization of the Camassa-Holm equation, the existence of solitary wave solutions, kink and anti-kink wave solutions, and uncountably infinite many breaking wave solutions, 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 exact explicit parametric representations of travelling wave solutions are listed. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the dynamics of discrete-time resonant tunneling diode (RTD)-based cellular neural networks is studied. By virtue of metric horseshoe theory, it can be shown that the map derived from the discretization of RTD-based cellular neural networks has horseshoe in terms of symbolic dynamics of , which means the map is semi-conjugate to 3-shift dynamics. [Copyright &y& Elsevier]

By using the method of dynamical systems, the travelling wave solutions of for an integrable nonlinear evolution equation is studied. Exact explicit parametric representations of kink and anti-kink wave, periodic wave solutions and uncountably infinite many smooth solitary wave solutions are given. [ABSTRACT FROM AUTHOR]

In this paper, the dynamics of discrete-time RTD-based cellular neural networks is studied. By virtue of topological horseshoe theory, it can be shown that the dynamics of the map derived from the discretization of RTD-based cellular neural networks is semi-conjugate to the dynamics of three-shift map. [ABSTRACT FROM AUTHOR]

In this letter, a model of discrete-time RTD-based cellular neural networks is considered. The chaotic behavior related to the existence of snap-back repellers given by Marotto's theorem is rigorously proved. The parameter regions exhibiting chaotic dynamics are determined. [ABSTRACT FROM AUTHOR]

By using the theory of bifurcations of planar dynamic systems to the coupled Jaulent-Miodek equations, the existence of smooth solitary travelling wave solutions and uncountably infinite many smooth periodic travelling wave solutions is studied and the bifurcation parametric sets are shown. Under the given parametric conditions, all possible representations of explicit exact solitary wave solutions and periodic wave solutions are obtained. [ABSTRACT FROM AUTHOR]

By finding a parabola solution connecting two equilibrium points of a planar dynamical system, the existence of the kink wave solution for 6 classes of nonlinear wave equations is shown. Some exact explicit parametric representations of kink wave solutions are given. Explicit parameter conditions to guarantee the existence of kink wave solutions are determined. [ABSTRACT FROM AUTHOR]

For a given system, by using the Tkachev method which concerned with the proof of the stability of a multiple limit cycle, the exact computation formula of the third separatrix values named by Leontovich for the multiple limit cycle bifurcation was given, which was one of the main criterions for the number of limit cycles bifurcated from a homoclinic orbit and the stability of the homoclinic loop, and a computation formula for higher separatrix values was conjectured. [ABSTRACT FROM AUTHOR]

By using the theory of the generalized perturbed Hamiltonian systems, it is shown that there exist periodic stream lines in the three-dimensional square cell pattern of Rayleigh-Benard convection. The result means that our method enables this three-dimensional flow pattern to be described in an unambiguous manner, and some experimental results of other authors can be explained. [ABSTRACT FROM AUTHOR]

The Superconducting Superconductor-Insulator-Superconductor (SIS) receivers have become the preferred method for (sub)millimeter-wave radio astronomical observations due to the extremely low receiver noise temperature. The coupling noise of the local oscillator (LO) system is also a part of the receiver noise. In many years of astronomical observations, it is found that the LO-coupled noise cannot be completely ignored, which has a certain impact on the sensitivity of astronomical observations. The noise temperature of the superconducting SIS receiver was tested using two different kinds of signal generators as the primary signal source of the LO system. It is found that the base noise output by the signal generator can be coupled into the receiver to increase the receiver noise. By adding a narrow band filter to the output of the signal generator, the base noise of the signal generator can be filtered out, and this part noise of the receiver can be eliminated, the overall noise of the receiver is reduced, and the sensitivity of the telescope is improved. [ABSTRACT FROM AUTHOR]

Background: To assess the efficacy of Nimotuzumab in combination with first-line chemoradiotherapy treatment in Chinese patients with primary III-IVb stage nasopharyngeal carcinoma.Methods: Patients with primary locoregionally advanced nasopharyngeal carcinoma who were treated with intensity-modulated radiotherapy (IMRT) and concurrent cisplatin-based chemotherapy between January 2008 and December 2013 at a single institution were retrospectively reviewed. Group A received at least 6 doses of Nimotuzumab, while Group B did not receive Nimotuzumab. A propensity score matching method was used to match patients from each group in a 1:3 ratio.Results: In total, 730 eligible patients were propensity matched, with 184 patients in Group A and 546 patients in Group B. Significant differences were not observed in the patient and tumor characteristics between Group A and Group B. At a median follow-up of 74.78 months (range 3.53-117.83 months), locoregional recurrence, distant failure and death were observed in 10.68, 11.10 and 16.03% of all patients, respectively. The estimated 5-year locoregional relapse-free survival, distant metastasis-free survival, progression-free survival and overall survival in the Group A versus Group B were 85.34% versus 89.79% (P = 0.156), 93.09% versus 85.61% (P = 0.012), 79.96% versus 77.99% (P = 0.117) and 88.91% versus 78.30% (P = 0.006), respectively.Conclusions: This nimotuzumab-containing regimen resulted in improved long-term survival of III-IVb stage NPC patients and warrants further prospective evaluation. [ABSTRACT FROM AUTHOR]

Delingha 13.7 m telescope is one of the most important radio telescopes in China. Since installing the superconducting spectroscopic array receiver (SSAR) and adopting the On The Fly (OTF) observation mode, the telescope has operated for nearly 10 years. During this period, a large number of astronomical observation projects have been carried out and completed, a large amount of astronomical data have been accumulated, and a series of important scientific results have been achieved. This paper introduces the operating status of SSAR in astronomical observations, the problems in operations, as well as the fault phenomena and solutions. The performance test and performance analysis of SSAR are described in detail, including the receiver noise temperature and telescope system noise temperature, image rejection ratio (IRR), receiver stability, beam performance and so on. The updating and development of SSAR are listed, including the automatic adjustment of LO (Local Oscillator) power, the updating of pre-amplification circuits of the sideband separation superconducting mixer, and the optimization of control program, etc. This paper summarizes the experiences and rules, and connects the past with the future, for applying the experiences of the maintenance and operation of SSAR to the next-generation large-scale receiver system. [ABSTRACT FROM AUTHOR]

This paper addresses delayed controller design in communication networks (CNs) with unstable open-loop system. Employing the Nyquist curve approach, the sufficient and necessary conditions of the gains and the delays, respectively, are obtained. The controllers are designed by using delayed positive output feedback. Some examples are presented to illustrate the effectiveness and simplicity of the designed controllers in both the time and frequency domains. [ABSTRACT FROM AUTHOR]

This paper addresses delayed controller design in communication networks (CNs) with unstable open-loop system. Employing the Nyquist curve approach, the sufficient and necessary conditions of the gains and the delays, respectively, are obtained. The controllers are designed by using delayed positive output feedback. Some examples are presented to illustrate the effectiveness and simplicity of the designed controllers in both the time and frequency domains. [ABSTRACT FROM AUTHOR]

This work describes the characterization and genome annotation of Salmonella phage vB_SalM_8-19 (referred to as 8-19) isolated from sewage samples collected in a pig farm in Jilin, China. This phage was capable of infecting 60% Salmonella strains in our lab stock. The genome of phage 8-19 is composed of linear double-stranded DNA that is 52,648 bp in length with a G + C content of 46.02%; containing 74 ORFs and no tRNA genes. In October 2019, phylogenetic analyses indicated that phage 8-19 might belong to a novel cluster among the other similar phages which have not been specifically classified within some new genus in family Myoviridae. Recently, the International Committee on Taxonomy of Viruses (ICTV) defined phage 8-19 and its related phages as genus Rosemountvirus, family Myoviridae. This new genus, known as Rosemountvirus, is rarely reported in the literature. [ABSTRACT FROM AUTHOR]

The attraction domain of memory patterns and exponential convergence rate of the network trajectories to memory patterns for continuous feedback associative memory are estimated again by using of some analysis techniques and Liapunov method, some new results are obtained, that can be used for evaluation of fault-tolerance capability and the synthesis procedures for continuous feedback associative memory neural networks. [ABSTRACT FROM AUTHOR]