Hybrid Stability Checking Method for Synchronization of Chaotic Fractional-Order Systems

A hybrid stability checking method is proposed to verify the establishment of synchronization between two hyperchaotic systems. During the design stage of a synchronization scheme for chaotic fractional-order systems, a problem is sometimes encountered. In order to ensure the stability of the error signal between two fractional-order systems, the arguments of all eigenvalues of the Jacobian matrix of the erroneous system should be within a region defined in Matignon’s theorem. Sometimes, the arguments depend on the state variables of the driving system, which makes it difficult to prove the stability. We propose a new and efficient hybrid method to verify the stability in this situation. The passivity-based control scheme for synchronization of two hyperchaotic fractional-order Chen-Lee systems is provided as an example. Theoretical analysis of the proposed method is validated by numerical simulation in time domain and examined in frequency domain via electronic circuits

Hidden attractors in fundamental problems and engineering models

Recently a concept of self-excited and hidden attractors was suggested: an attractor is called a self-excited attractor if its basin of attraction overlaps with neighborhood of an equilibrium, otherwise it is called a hidden attractor. For example, hidden attractors are attractors in systems with no equilibria or with only one stable equilibrium (a special case of multistability and coexistence of attractors). While coexisting self-excited attractors can be found using the standard computational procedure, there is no standard way of predicting the existence or coexistence of hidden attractors in a system. In this plenary survey lecture the concept of self-excited and hidden attractors is discussed, and various corresponding examples of self-excited and hidden attractors are considered

The effects of Chinese proprietary medicine and vaccination on patients with COVID-19: a retrospective study in Macao

Abstract Background COVID-19 is continuing to ravage globally and has resulted in a huge health and financial burden. Chinese proprietary medicines, such as Lianhua Qingwen (LHQW) and Huoxiang Zhengqi (HXZQ) capsules, have been recommended for non-high-risk patients with COVID-19 in China. Based on this, we described the baseline information, using status of LHQW and HXZQ capsules and inoculation history of quarantined patients in the second half of 2022 in Macao. Additionally, we analyzed the underlying association among medicines administration, vaccination and COVID-19 indices, in order to explore novel clues for the regular control and prevention of local epidemic situation in the future. Methods A total of 976 patients in Macao quarantine hotels from June to August 2022 were included in the present study, of which, 857 subjects were followed-up for prognosis evaluation. During quarantine, the baseline demographic information, including sex, age, BMI, occupation and personal habits were collected. Additionally, the inoculation history, medicine employment status and cycle threshold (Ct) values were also reported. We interviewed the patients for collection of their symptoms at the beginning and end of quarantine, as well as prognostic ones. Basic statistical description of baseline information, vaccination history and medication were displayed. Chi-squared test or with continuous correction test was employed for comparison of dichotomous data between two or multiple groups. Binary logistic regression was applied to reveal the correlation between potential risk factors and Ct values or prognosis symptoms. We also used Cox regression model to identify the effect of different types of vaccine products on Ct value altering rate. Results Patients who were female (52.0%), engaged in service industry (31.8%), from Macao native (65.8%), never took physical exercises (33.6%) and preferred irritated diet (59.5%) enjoyed more dominant proportions. Over 80% of participants were inoculated and 74.6% of them chose inactivated COVID-19 vaccine produced by China National Biotech Group (CNBG). Participants used LHQW capsules accounted for 92.1% and the duration of medicating lasted for one to two weeks. All of the reported symptoms were significantly ameliorated after quarantine and the duration of quarantine was concentrated on 21 days. People with different age, sex, occupation and region had different choices of HXZQ administration and vaccination. Additionally, middle dose (4–5 boxes) of LHQW capsules exhibited evidently negative association with positive Ct values (adjusted, − 0.037 ± 0.19, p = 0.04). Two doses of CNBG and one dose of mRNA vaccine had obvious protective effect on reducing Ct positive rate (p = 0.041). Meanwhile, symptoms after quarantine were significantly positive correlated with those in prognosis (adjusted, 1.38 ± 0.18, p < 0.0001). Conclusion Our study found that the administration of LHQW capsules was beneficial for Ct value turning negative, meanwhile, certain mixed inoculation may be the promoting factor to reduce the positive rate of Ct value. These findings provide data basis for the Chinese proprietary medicine treatment and mixed vaccination applying for prevention and control of local COVID-19 epidemic in the future

Lung adenocarcinoma promotion by air pollutants

A complete understanding of how exposure to environmental substances promotes cancer formation is lacking. More than 70 years ago, tumorigenesis was proposed to occur in a two-step process: an initiating step that induces mutations in healthy cells, followed by a promoter step that triggers cancer development1. Here we propose that environmental particulate matter measuring ≤2.5 μm (PM2.5), known to be associated with lung cancer risk, promotes lung cancer by acting on cells that harbour pre-existing oncogenic mutations in healthy lung tissue. Focusing on EGFR-driven lung cancer, which is more common in never-smokers or light smokers, we found a significant association between PM2.5 levels and the incidence of lung cancer for 32,957 EGFR-driven lung cancer cases in four within-country cohorts. Functional mouse models revealed that air pollutants cause an influx of macrophages into the lung and release of interleukin-1β. This process results in a progenitor-like cell state within EGFR mutant lung alveolar type II epithelial cells that fuels tumorigenesis. Ultradeep mutational profiling of histologically normal lung tissue from 295 individuals across 3 clinical cohorts revealed oncogenic EGFR and KRAS driver mutations in 18% and 53% of healthy tissue samples, respectively. These findings collectively support a tumour-promoting role for PM2.5 air pollutants and provide impetus for public health policy initiatives to address air pollution to reduce disease burden