Switching-based stabilization of aperiodic sampled-data Boolean control networks with all subsystems unstable

We aim to further study the global stability of Boolean control networks(BCNs)under aperiodic sampleddata control(ASDC).According to our previous work,it is known that a BCN under ASDC can be transformed into a switched Boolean network(SBN),and further global stability of the BCN under ASDC can be obtained by studying the global stability of the transformed SBN.Unfortunately,since the major idea of our previous work is to use stable subsystems to offset the state divergence caused by unstable subsystems,the SBN considered has at least one stable subsystem.The central thought in this paper is that switching behavior also has good stabilization;i.e.,the SBN can also be stable with appropriate switching laws designed,even if all subsystems are unstable.This is completely different from that in our previous work.Specifically,for this case,the dwell time(DT)should be limited within a pair of upper and lower bounds.By means of the discretized Lyapunov function and DT,a sufficient condition for global stability is obtained.Finally,the above results are demonstrated by a biological example.

Qidong hepatitis B virus infection cohort: a 25-year prospective study in high risk area of primary liver cancer

Qidong hepatitis B virus (HBV) infection cohort (QBC) is a prospective community-based study designed to investigate causative factors of primary liver cancer (PLC) in Qidong, China, where both PLC and HBV infection are highly endemic. Residents aged 20-65 years, living in seven townships of Qidong, were surveyed using hepatitis B surface antigen (HBsAg) serum test and invited to participate in QBC from June 1991 to December 1991. A total of 852 and 786 participants were enrolled in HBsAg-positive and HBsAg-negative sub-cohorts in May 1992, respectively. All participants were actively followed up in person, received HBsAg, alanine aminotransferase, alpha-fetoprotein tests and upper abdominal ultrasonic examination, and donated blood and urine samples once or twice a year. The total response rate was 99.6%, and the number of incident PLC was 201 till the end of February 2017. The ratio of incidence rates was 12.32 [95% confidence interval (CI): 7.16-21.21, P < 0.0001] in HBsAg-positive arm compared with HBsAg-negative arm. The relative risk of PLC was 13.25 (95%CI: 6.67-26.33, P < 0.0001) and 28.05 (95% CI: 13.87-56.73, P < 0.0001) in the HBsAg+/HBeAg-group and the HBsAg+/HBeAg+ group, respectively, as compared to the HBsAg-/HBeAg- group. A series of novel PLC-related mutations including A2159G, A2189C and G2203W at the C gene, A799G, A987G and T1055A at the P gene of HBV genome were identified by using samples from the cohort. The mutation in HBV basal core promoter region of HBV genome has an accumulative effect on the occurrence of PLC. In addition, the tripartite relationship of aflatoxin exposure, P53 mutation and PLC was also investigated. QBC will be used to develop dynamic prediction model for PLC risk by using its long-term follow-up information and serial blood samples. This model is expected to improve the efciency of PLC screening in HBV infection individuals.

Complex systems and networks with their applications

Complex systems and networks capture most of the features in existing systems and have gained considerable attention over the past several decades.In recent years,research has extended to the fields of networked control systems,cyber-physical systems,logical networks,neural networks,and related topics.This is mainly due to rapid developments in commu nication,computer,and information technologies,which enable the handling of large-scale data that cannot be easily handled via traditional methods.