Dynamical Behavior of Nonautonomous Stochastic Reaction-Diffusion Neural Network Models

This brief investigates nonautonomous stochastic reaction-diffusion neural-network models with S-type distributed delays. First, the existence and uniqueness of mild solution are studied under the Lipschitz condition without the linear growth condition. Due to the existence of a nonautonomous reaction-diffusion term and the infinite dimensional Wiener process, the criteria for the well-posedness of the models are established based on the evolution system theory. Then, the S-type distributed delay, which is an infinite delay, is handled by the truncation method, and sufficient conditions for the global exponential stability are obtained by constructing a simple Lyapunov-Krasovskii functional candidate. Finally, neural-network examples and an illustrative example are given to show the applications of the obtained results.</p

Learning non-negativity constrained variation for image denoising and deblurring

This paper presents a heuristic Learning-based Non-Negativity Constrained Variation (L-NNCV) aiming to search the coefficients of variational model automatically and make the variation adapt different images and problems by supervised-learning strategy. The model includes two terms: a problem-based term that is derived from the prior knowledge, and an image-driven regularization which is learned by some training samples. The model can be solved by classical o-constraint method. Experimental results show that: the experimental effectiveness of each term in the regularization accords with the corresponding theoretical proof; the proposed method outperforms other PDE-based methods on image denoising and deblurring.</p

Finite-Time Boundedness of Impulsive Delayed Reaction–Diffusion Stochastic Neural Networks

Considering the impulsive delayed reaction&amp;#x2013;diffusion stochastic neural networks (IDRDSNNs) with hybrid impulses, the finite-time boundedness (FTB) and finite-time contractive boundedness (FTCB) are investigated in this article. First, a novel delay integral inequality is presented. By integrating this inequality with the comparison principle, some sufficient conditions that ensure the FTB and FTCB of IDRDSNNs are obtained. This study demonstrates that the FTB of neural networks with hybrid impulses can be maintained, even in the presence of impulsive perturbations. And for a system that is not FTB due to impulsive perturbations, achieving FTB is possible through the implementation of appropriate impulsive control and optimization of the average impulsive intervals. In addition, to validate the practicality of our results, three illustrative examples are provided. In the end, these theoretical findings are successfully applied to image encryption.</p

Stability of stochastic impulsive reaction-diffusion neural networks with S-type distributed delays and its application to image encryption

In this paper, we study stochastic impulsive reaction-diffusion neural networks with S-type distributed delays, aiming to obtain the sufficient conditions for global exponential stability. First, an impulsive inequality involving infinite delay is introduced and the asymptotic behaviour of its solution is investigated by the truncation method. Then, global exponential stability in the mean-square sense of the stochastic impulsive reaction-diffusion system is studied by constructing a simple Lyapunov-Krasovskii functional where the S-type distributed delay is handled by the impulsive inequality. Numerical examples are also given to verify the effectiveness of the proposed results. Finally, the obtained theoretical results are successfully applied to an image encryption scheme based on bit-level permutation and the stochastic neural networks.</p

Finite-Time Boundedness of Impulsive Delayed Reaction–Diffusion Stochastic Neural Networks

Considering the impulsive delayed reaction&amp;#x2013;diffusion stochastic neural networks (IDRDSNNs) with hybrid impulses, the finite-time boundedness (FTB) and finite-time contractive boundedness (FTCB) are investigated in this article. First, a novel delay integral inequality is presented. By integrating this inequality with the comparison principle, some sufficient conditions that ensure the FTB and FTCB of IDRDSNNs are obtained. This study demonstrates that the FTB of neural networks with hybrid impulses can be maintained, even in the presence of impulsive perturbations. And for a system that is not FTB due to impulsive perturbations, achieving FTB is possible through the implementation of appropriate impulsive control and optimization of the average impulsive intervals. In addition, to validate the practicality of our results, three illustrative examples are provided. In the end, these theoretical findings are successfully applied to image encryption.</p

Observer-based event-triggered impulsive control of delayed reaction-diffusion neural networks

In this paper, we present a novel design of an observer-based event-triggered impulsive control strategy for delayed reaction-diffusion neural networks subject to impulsive perturbation. The impulsive instants of impulsive control are determined in an event-triggered way, and the control strength is designed by the sampling output of an impulsive observer. Several criteria with Lyapunov conditions and linear matrix inequalities are established for the global exponential stability of delayed reaction-diffusion neural networks. It inherits the advantages of event-triggered impulsive control such as low triggering frequency and high efficiency, and is applicable for networks with unmeasurable states. Finally, the effectiveness of theoretical results is verified by a numerical example

Adaptive synchronization of stochastic complex dynamical networks and its application

This paper investigates exponential synchronization for stochastic complex dynamical networks with reaction–diffusion terms and S-type distributed delays. Based on a generalized Halanay inequality and Poincaré inequality, adaptive control strategies for exponential synchronization are established by constructing a simple Lyapunov–Krasovskii functional candidate and utilizing the truncation method. Some numerical examples are provided to demonstrate the effectiveness of the obtained results. Finally, the proposed adaptive synchronization theoretical results are successfully applied to image encryption.</p

Willingness to pay and price elasticity of demand for long-acting injectable cabotegravir among men who have sex with men in Guangxi, China

ObjectivesThere is still no study focused on willingness to pay for long-acting injectable cabotegravir (CAB-LA) after it was available on the market in the United States in 2021. Here, we explored the willingness to pay for CAB-LA and associated factors and price elasticity of demand (PED) of CAB-LA among men who have sex with men (MSM) in Guangxi, China.MethodsA cross-sectional study was conducted. Univariate and multivariate ordinal logistic regression analyses were performed to explore the associated factors of willingness to pay for CAB-LA. PED was used to measure the change in the number of participants willing to pay to a change in price.ResultsA total of 1,006 MSM were recruited, among which 84.1% were aged between 18 and 39 years old. The median (interquartile) of the maximum amount of willing to pay for CAB-LA was 200 (100–500) Chinese yuan (CNY) per month. Most (84.2%) were willing to pay less than 600 CNY per month. The number of participants willing to pay for CAB-LA significantly increased with decrease in the price. When the price (CNY per month) decreased from 600 to 500, 500 to 400, 400 to 300, and 300 to 200, PED was 3.13, 1.64, 1.33, and 1.17, respectively. The maximum amount of willing to pay for CAB-LA was positively associated with younger age (vs. ≥40 years group, 18–24 years group, aOR: 1.94, 95% CI: 1.32–2.85; 25–39 year group, aOR: 1.70, 95% CI: 1.20–2.42), being high educated (vs. middle school or lower group, high school or college group, aOR: 1.61, 95% CI: 1.06–2.48; bachelor’s degree or above group, aOR: 2.21, 95% CI: 1.41–3.49), monthly income ≥6000 CNY (vs. &lt;3000 CNY, aOR: 1.46, 95% CI: 1.02–2.09), being bisexual/unsure sexual orientation (vs. gay, aOR: 1.73, 95% CI: 1.24–2.43), and heard of PrEP and used (vs. never heard of PrEP, aOR: 1.76, 95% CI: 1.11–2.77).ConclusionThe maximum amount of willing to pay for CAB-LA was low in Guangxi, China. PED of CAB-LA is relatively elastic. The waived patent protection should be considered for the wide promotion of CAB-LA, and the health education should be strengthened to improve the recognition of CAB-LA

Ethnic discordance in serum anti-Müllerian hormone in healthy women: a population study from China and Europe

Research question: Chinese women are known to have an earlier age of natural menopause than their European counterparts, but whether they also have a lower functional ovarian reserve is unknown. This study was designed to assess whether there are ethnic differences in anti-Müllerian hormone (AMH) concentrations in women of reproductive age. Design: Women in China and Europe with regular menstrual cycles, not on hormonal contraception and with no medical history of note, were recruited to provide a day 2–5 early follicular phase sample. AMH concentration was determined using the Roche Elecsys assay. Decline in AMH was modelled with linear, quadratic and quadratic with interaction on age equations to assess the impact of ethnicity. Results: A total of 887 European and 461 Chinese women participated in the study. Despite the Chinese population being slightly younger (34.1 ± 8.4 years) than their European counterparts (34.8±8.9 years), their median AMH was lower, at 1.87 ng/ml (interquartile range [IQR] 0.28–3.64) compared with 2.11 ng/ml (IQR 0.73–3.96), with evidence of increasing discordance from age 25 years. In all regression models of the age-related decline in AMH, there was evidence of a difference between Chinese and European women. Although AMH was 28.1% (95% confidence interval [CI] 18.2–36.7%) lower in the Chinese population at age 30, this decline increased to 79.4% (95% CI 75.4– 82.9%) at age 45. Conclusions: There were independent effects of age and ethnicity on serum AMH concentrations, with Chinese women having a substantially lower AMH in adult life than their European counterparts from age 25 onwards

Metabolomics Analytics Workflow for Epidemiological Research: Perspectives from the Consortium of Metabolomics Studies (COMETS)

The application of metabolomics technology to epidemiological studies is emerging as a new approach to elucidate disease etiology and for biomarker discovery. However, analysis of metabolomics data is complex and there is an urgent need for the standardization of analysis workflow and reporting of study findings. To inform the development of such guidelines, we conducted a survey of 47 cohort representatives from the Consortium of Metabolomics Studies (COMETS) to gain insights into the current strategies and procedures used for analyzing metabolomics data in epidemiological studies worldwide. The results indicated a variety of applied analytical strategies, from biospecimen and data pre-processing and quality control to statistical analysis and reporting of study findings. These strategies included methods commonly used within the metabolomics community and applied in epidemiological research, as well as novel approaches to pre-processing pipelines and data analysis. To help with these discrepancies, we propose use of open-source initiatives such as the online web-based tool COMETS Analytics, which includes helpful tools to guide analytical workflow and the standardized reporting of findings from metabolomics analyses within epidemiological studies. Ultimately, this will improve the quality of statistical analyses, research findings, and study reproducibility