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Patients with severe mental illnesses (SMI) were at high risk of infection during Coronavirus Diseases 2019 (COVID-19) pandemic. This study examined hospitalized SMI patients' attitude and knowledge towards the COVID-19 infection. A cross-sectional survey was conducted in five psychiatric hospitals located in Gansu province, the most economically underdeveloped area in China. Patients' attitude towards preventive measures and knowledge of COVID-19 were measured by a self-report questionnaire. A total of 925 hospitalized patients with SMI were recruited. Of them, 84.8% (95%CI: 82.4%–87.1%) had positive attitudes towards preventive measures of the COVID-19 outbreak. Being married (OR: 1.55, 95%CI: 1.05–2.30) and a higher educational level (OR: 1.63, 95%CI: 1.12–2.38) were independently associated with positive attitudes towards COVID-19 preventive measures, whereas higher educational level was associated with better knowledge of the COVID-19 outbreak (β: 0.231, P < 0.001). Patients mainly received COVID-19 relevant knowledge from public media (58.9%), followed by their clinicians (33.2%). Most hospitalized SMI patients in economically underdeveloped areas in China showed positive attitudes towards COVID-19 preventive measures. However, public health education on COVID-19 relevant knowledge by mental health professionals was inadequate to reduce the risk of transmission and infection. [ABSTRACT FROM AUTHOR]

The Kirchhoff index K f (G) of a graph G is defined to be the sum of the resistance distances between all pairs of vertices of G. In this paper, we develop a novel method for ordering the Kirchhoff indices of the complements of trees and unicyclic graphs. With this method, we determine the first five maximum values of K f ( T ¯ ) and the first four maximum values of K f (Ū), where T ¯ and Ū are the complements of a tree T and unicyclic graph U, respectively. [ABSTRACT FROM AUTHOR]

In this study, we investigate the problem of multiple Mittag-Leffler stability analysis for fractional-order quaternion-valued neural networks (QVNNs) with impulses. Using the geometrical properties of activation functions and the Lipschitz condition, the existence of the equilibrium points is analyzed. In addition, the global Mittag-Leffler stability of multiple equilibrium points for the impulsive fractional-order QVNNs is investigated by employing the Lyapunov direct method. Finally, simulation is performed to illustrate the effectiveness and validity of the main results obtained. [ABSTRACT FROM AUTHOR]

A model of damage to fresh concrete in a corrosive sulphate environment was formulated to investigate how and why the strength of corroded concrete changes over time. First, a corroded concrete block was divided into three regions: an expanded and dense region; a crack-development region; and a noncorroded region. Second, based on the thickness of the surface corrosion layer and the rate of loss of compressive strength of the corroding region, a computational model of the concrete blocks' corrosion-resistance coefficient of compressive strength in a sulphate environment was generated. Third, experimental tests of the corrosion of concrete were conducted by immersing specimens in a corrosive medium for 270 d. A comparison of the experimental results with the computational formulae shows that the calculation results and test results are in good agreement. A parameter analysis reveals that the corrosion reaction plays a major role in the corrosion of fresh concrete containing ordinary Portland cement, but the diffusion of the corrosion medium plays a major role in the corrosion of concrete mixtures containing fly ash and sulphate-resistant cement. Fresh concrete with a high water-to-cement ratio shows high performance during the whole experiment process whereas fresh concrete with a low water-to-cement ratio shows poor performance during the late experiment period. [ABSTRACT FROM AUTHOR]

The article presents a study that examined the time-frequency characteristics of spike waves for detecting epilepsy symptoms using the Hilbert-Huang transform (HHT) analysis method. Topics include Pearson correlation coefficients, weighted average frequency, weighted average magnitude, and HHT decomposition.

The article discusses the use of a three-level chaos-based eletroencephalogram (EEG) encryption level developed with the Microsoft Visual Studio Development Kit and C# programming architectures. Topics discussed include the EEG testing used to describe brain waves associated with epilepsy and other diseases, the testing performed with eight 16-channel EEG Vue signals, as well as the presence of chaotic bit streams negating EEG Vue signals recovery.

Two new compounds, rabdosia acids A ( 1) and B ( 2), were isolated from the petroleum ether extract of Rabdosia lophanthoides. The structures of these compounds were elucidated on the basis of spectroscopic methods (IR, HR-ESI-MS, 1D NMR, and 2D NMR). [ABSTRACT FROM AUTHOR]

Abstract  In this article, the global exponential robust stability is investigated for Cohen–Grossberg neural network with both time-varying and distributed delays. The parameter uncertainties are assumed to be time-invariant and bounded, and belong to given compact sets. Applying the idea of vector Lyapunov function, M-matrix theory and analysis techniques, several sufficient conditions are obtained to ensure the existence, uniqueness, and global exponential robust stability of the equilibrium point for the neural network. The methodology developed in this article is shown to be simple and effective for the exponential robust stability analysis of neural networks with time-varying delays and distributed delays. The results obtained in this article extend and improve a few recently known results and remove some restrictions on the neural networks. Three examples are given to show the usefulness of the obtained results that are less restrictive than recently known criteria. [ABSTRACT FROM AUTHOR]

The estimation problem for diffusion coefficients in diffusion processes has been studied in many papers, where the diffusion coefficient function is assumed to be a 1-dimensional bounded Lipschitzian function of the state or the time only. There is no previous work for the nonparametric estimation of time-dependent diffusion models where the diffusion coefficient depends on both the state and the time. This paper introduces and studies a wavelet estimation of the time-dependent diffusion coefficient under a more general assumption that the diffusion coefficient is a linear growth Lipschitz function. Using the properties of martingale, we translate the problems in diffusion into the nonparametric regression setting and give the L r convergence rate. A strong consistency of the estimate is established. With this result one can estimate the time-dependent diffusion coefficient using the same structure of the wavelet estimators under any equivalent probability measure. For example, in finance, the wavelet estimator is strongly consistent under the market probability measure as well as the risk neutral probability measure. [ABSTRACT FROM AUTHOR]

In this article, the recent research achievements on the theory and technology of condensate oil and gas wells stimulated by electromagnetic induction heating during middle or late exploitation period were introduced for the first time at home and abroad. A new kind of electromagnetic wave induction heating equipment XAEMH-1 was developed. Taking near wellbore zone temperature field as the main research object, which is the key factor for the condensation and retrograde vaporization during electromagnetic heating, the mathematical simulation model for a condensate oil and gas well stimulated by electromagnetic heating to eliminate blockage near wellbore region was established. A corresponding computer system was developed to dynamically predict and evaluate the efficiency of this electromagnetic heating process. Through this computer system, the near wellbore region distributions of several important factors such as temperature, pressure, condensate oil saturation and relative permeability can be described quantitatively. A condensate gas well in a late exploitation period reservoir here in China was chosen as a practical example to test the effectiveness of this new technology and some satisfactory results were obtained. These results proved that it is feasible to eliminate the near wellbore region blockage by electromagnetic heating. A new prospective stimulation method was given for the condensate oil and gas reservoirs during middle or late exploitation period. [ABSTRACT FROM AUTHOR]

Transfer of the herpes simplex virus type I-thymidine kinase gene, followed by the administration of ganciclovir (HSV1-tk/GCV) into ovarian cancer-derived cell line either in vitro or transplanted into nude mice has been shown to provide a potential strategy for the gene therapy of ovarian cancer. We investigated the antitumor effects of HSV1-tk/GCV strategy with a chemically induced rat ovarian cancer model and a tumor-selective gene delivery by a novel nonviral gene delivery system (GE7) through the ovarian artery and tail vein. We demonstrated the expression of a reporter gene, β-gal gene, as well as HSV1-tk gene in tumors and other organs, evaluated the overall antitumor effects after the GCV treatment and analyzed the tumor cell cycle phase distribution. Via the ovarian artery route, the expressions of β-gal and HSV1-tk in tumors were significantly stronger than those expressed in such organs as the hearts, livers, spleens, lungs and kidneys. However, no β-gal and HSV1-tk were detected in the tumor tissues when administrated via the tail vein, and little was found in other organs. The cell cycle analysis showed that the total S-phase of tumor cells in the test intra-arterial treatment group was considerably higher than that of the controls. The weight of the tumor tissues in the group treated by the intra-arterial route (4.06±2.12 g) was much less than the group treated intravenously (18.25±8.34 g) (P<.01). These findings indicated that the administration of GE7/HSV1-tk complex via the ovarian artery route could be a promising avenue of future human ovarian cancer treatment.Cancer Gene Therapy (2005) 12, 810–817. doi:10.1038/sj.cgt.7700845; published online 20 May 2005 [ABSTRACT FROM AUTHOR]

Utilizing the Liapunov functional method and combining the inequality of matrices technique to analyze the existence of a unique equilibrium point and the global asymptotic stability for delayed cellular neural networks (DCNNs), a new sufficient criterion ensuring the global stability of DCNNs is obtained. Our criteria provide some parameters to appropriately compensate for the tradeoff between the matrix definite condition on feedback matrix and delayed feedback matrix. The criteria can easily be used to design and verify globally stable networks. Furthermore, the condition presented here is independent of the dalay parameter and is less restrictive than that given in the references. [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 procedure for continuous feedback associative memory neural networks. [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]

Despite significant progress in the fabrication and application of semiconductor materials for optical emitters and sensors, few materials can cover the cyan-gap between 450 and 500 nm. We here introduce a robust and facile method to deposit amorphous Sb2S3 films with a bandgap of 2.8 eV. By exploiting the tunable functionality of graphene, a two-dimensional material, efficient deposition from a chemical was achieved. Ozone-generated defects in the graphene were shown to be required to enhance the morphology and quality of the material and comprehensive characterization of the seed layer and the Sb2S3 film were applied to design an optimal deposition process. The resulting material exhibits efficient carrier transport and high photodetector performance as evidenced by unprecedented responsivity and detectivity in semiconductor/graphene/glass vertical heterostructures. (112 A/W, 2.01 × 1012 Jones, respectively). [ABSTRACT FROM AUTHOR]

This paper is devoted to the passivity analysis of an array model for coupled inertial delayed neural networks (NNs) with impulses under different network structures, namely directed and undirected topologies. Firstly, utilising the information of eigenvectors for the directed coupling matrix, a new Lyapunov functional is constructed, by which, together with the aid of some inequality techniques and network characteristics, the two sets of sufficient criteria are established to, respectively, guarantee the strictly input passivity and strictly output passivity of the impulsive network with directed coupling. Secondly, benefited from the properties of the undirected coupling matrix, some more concise conditions that are easier to be verified for the passivities of the undirected coupled network accompanied by impulsive effects are proposed. Finally, two numerical examples are designed to execute the verification of the derived theoretical results. [ABSTRACT FROM AUTHOR]