H∞ Control for Stochastic Singular Systems With Time-Varying Delays via Sampled-Data Controller.

In this article, H∞ control for stochastic singular time-varying delay systems under arbitrarily variable samplings is addressed via designing a sampled-data controller. The first and foremost, a novel time-dependent discontinuous Lyapunov-Krasovskii (L-K) functional is built, which takes good advantage of the factual sampling pattern's available properties. Then, based on the refined input delay method by utilizing the constructed time-dependent L-K functional, the free-weighting matrix method, and the auxiliary vector function approach are adopted to develop conditions ensuring the stochastic admissibility for the studied stochastic singular systems with time-varying delays. On the basis of the derived conditions, the sampled-data H∞ control issue is tackled, and an unambiguous expression for the sampled-data controller design method is obtained. Finally, simulation examples manifest that our proposed results are correct and effective.

CASP3 genetic variants and susceptibility to atrial fibrillation in Chinese Han population.

BACKGROUND: Caspase-3 plays an important role in the initiation and maintenance of atrial fibrillation (AF), but little is known about the role of CASP3 variants in the susceptibility to atrial fibrillation (AF). The purpose of this study was to comprehensively investigate the association between common genetic variants of CASP3 gene and AF in Chinese Han population. METHODS AND RESULTS: We investigated the association of five variants in CASP3 and the risk of AF in 889 AF patients and 1015 controls. The genotype distribution of the rs4647602 was significantly different between patients with AF and controls (p<0.001), and the A allele frequency was significantly higher in AF patients than in controls (61.0% vs 53.2%; p<0.001). Compared with CC genotype carriers, subjects with AA genotype had significantly increased susceptibility to AF (OR=1.84, p<0.001). Multivariable logistic regression analysis showed that the rs4647602 polymorphism was significantly associated with risk of AF under dominant, recessive and additive genetic model (OR, 1.44-1.64; all p<0.001). There was no association between the other four SNPs (rs6948, rs2696056, rs4647602 and rs4647610) and risk of AF. CONCLUSION: The rs4647602 polymorphism is independently associated with the risk of AF in Chinese Han population.

A complex-valued neural dynamical optimization approach and its stability analysis.

In this paper, we propose a complex-valued neural dynamical method for solving a complex-valued nonlinear convex programming problem. Theoretically, we prove that the proposed complex-valued neural dynamical approach is globally stable and convergent to the optimal solution. The proposed neural dynamical approach significantly generalizes the real-valued nonlinear Lagrange network completely in the complex domain. Compared with existing real-valued neural networks and numerical optimization methods for solving complex-valued quadratic convex programming problems, the proposed complex-valued neural dynamical approach can avoid redundant computation in a double real-valued space and thus has a low model complexity and storage capacity. Numerical simulations are presented to show the effectiveness of the proposed complex-valued neural dynamical approach.

Association between SNP rs13376333 and rs1131820 in the KCNN3 gene and atrial fibrillation in the Chinese Han population.

BACKGROUND: The small conductance calcium-activated potassium, subfamily N, member 3 (KCNN3) gene rs13376333 and rs1131820 have been shown to be strongly associated with lone atrial fibrillation (AF), while replication association studies between rs13376333 in KCNN3 gene and risk of AF showed conflicting results. The current study tried to validate the impact of SNP rs13376333 and rs1131820 of KCNN3 gene on the risk of AF in the Chinese Han population. METHODS: A total of 889 AF patients and 1015 controls were enrolled. Two hundred and seventy-eight cases of AF were lone AF. KCNN3 gene SNP rs13376333 and rs1131820 were genotyped by allele-specific MALDI-TOF mass spectrometry. RESULTS: The genotype distribution and allele frequency of rs13376333 polymorphism were not different between total AF patients and controls. However, the genotype distribution of rs13376333 polymorphism was significantly different between lone AF and control group (p<0.001); and T allele frequency was significantly higher in lone AF group than that in controls (7.6% vs 3.6%, p<0.001). Multivariable logistic regression analysis showed that T allele carriers of rs13376333 was significantly associated with lone AF (OR=2.31, 95% CI 1.41-3.78, p=0.001). No relationship between rs1131820 polymorphism and total AF or lone AF was found in this study. CONCLUSIONS: KCNN3 rs13376333 polymorphism was associated with lone AF in the Chinese Han population and the T allele carriers may be an independent predictive factor for lone AF.

TheTGFB1 functional polymorphism rs1800469 and susceptibility to atrial fibrillation in two Chinese Han populations.

Transforming growth factor-ß1 (TGF-ß1) is related to the degree of atrial fibrosis and plays critical roles in the induction and perpetuation of atrial fibrillation (AF). To investigate the association of the common promoter polymorphism rs1800469 in the TGF-ß1 gene (TGFB1) with the risk of AF in Chinese Han population, we carried out a case-control study of two hospital-based independent populations: Southeast Chinese population (581 patients with AF and 723 controls), and Northeast Chinese population (308 AF patients and 292 controls). Two hundred and seventy-eight cases of AF were lone AF and 334 cases of AF were diagnosed as paroxysmal AF. In both populations, AF patients had larger left atrial diameters than the controls did. The rs1800469 genotypes in the TGFB1 gene were determined by polymerase chain reaction-restriction fragment length polymorphism. The genotype and allele frequencies of rs1800469 were not different between AF patients and controls of the Southeast Chinese population, Northeast Chinese population, and total Study Population. After adjustment for age, sex, hypertension and LAD, there was no association between the rs1800469 polymorphism and the risk of AF under the dominant, recessive and additive genetic models. Similar results were obtained from subanalysis of the lone and paroxymal AF subgroups. Our results do not support the role of the TGFB1 rs1800469 functional gene variant in the development of AF in the Chinese Han population.

[A study of relationship between dialectical classification according to traditional Chinese medicine of acute coronary syndrome with serum osteoprotegerin and its ligand].

OBJECTIVE: To investigate the relationship between osteoprotegerin (OPG) system and acute coronary syndrome (ACS) and its classification according to traditional Chinese medicine (TCM). METHODS: A prospective study was conducted. The patients with ACS (n=210) and the patients with stable angina pectoris (SAP, n=200) were enrolled. The serum OPG and its ligand (sRANKL) were determined by enzyme-linked immunosorbent assay (ELISA), the OPG/sRANKL ratio was calculated, and the number of coronary vessels was involved, finally their relationship with the typing according to TCM was evaluated. One hundred and fifty non-coronary heart disease patients were enrolled as control. RESULTS: The serum OPG, OPG/sRANKL in ACS and SAP groups were significantly higher than those in control group, and the sRANKL was significantly lower than that in control group (all P<0.01). The OPG, OPG/sRANKL in ACS groups were significantly higher than those in SAP group (both P<0.01). Serum OPG, OPG/sRANKL in ACS patients with different number of coronary vessel disease were significantly higher than those in control group, and the sRANKL was significantly lower than that in control group (all P<0.01). OPG and OPG/sRANKL were gradually increased with increase in number of diseased coronary vessels, but the sRANKL descended (P<0.05 or P<0.01). Serum OPG and OPG/sRANKL were descended according to dialectical classification of TCM: Yang Qi weakening syndrome>Qi and blood stagnation syndrome>Qi deficiency with blood stasis syndrome>stagnation of phlegm blocks the heart-vessels syndrome>Yin deficiencies of the heart and the kidney syndrome>deficiency of both Qi and Yin syndrome, among them they were significantly higher in Yang Qi failure syndrome and Qi and blood stagnation syndromes than those of both Qi and Yin syndrome [OPG(ng/L): 621.38±32.86, 617.63±39.60 vs. 593.86±36.19, OPG/sRANKL(g/mol): 1 018.98±106.03, 1 011.27±121.61 vs. 942.16±115.82, P<0.05 or P<0.01]. Among different types of TCM in ACS group the serum sRANKL was significantly lower than that in control group (all P<0.01), but the difference among different types was not significant. CONCLUSIONS: Serum OPG, sRANKL, OPG/sRANK levels were related with incidence and severity of coronary lesions in ACS patients. Serum OPG and OPG/sRANKL ratio may have correlation with Yang Qi weakening syndrome and Qi deficiency with blood stasis syndrome.

The impact of acute atrial fibrillation on the prothrombotic state in patients with essential hypertension.

OBJECTIVES: To investigate whether acute atrial fibrillation (AF) creates a prothrombotic state in hypertensive patients, and to assess the evolution in research indices after cardioversion. DESIGN AND METHODS: Plasma levels of von Willebrand factor (vWf), soluble P-selectin and fibrin D-dimers were measured in hypertensive patients with acute AF pre-cardioversion and at 1, 7, 14, and 30days post-cardioversion. The results were compared with hypertensive controls and healthy controls. RESULTS: Pre-cardioversion plasma vWf levels in acute AF patients were similar to those of controls; however, post-cardioversion, the vWf levels increased significantly and only returned to baseline levels 14days later. Compared with controls, acute AF patients had higher levels of fibrin D-dimers, which lasted at least 14days after cardioversion. CONCLUSIONS: This study demonstrated that hypertensive patients with acute AF have an abnormal prothrombotic state, which persists for up to 14days after cardioversion.

MMP-2 and TIMP-2 gene polymorphisms and susceptibility to atrial fibrillation in Chinese Han patients with hypertensive heart disease.

BACKGROUND: MMP-2 and TIMP-2 play important roles in the pathogenesis of arrhythmogenic atrial remodeling, and may contribute to the development and persistence of atrial fibrillation (AF). Functional polymorphisms in the promoter of MMP-2 and TIMP-2 gene may modulate an individual's susceptibility to AF. METHODS: A total of 881 hypertensive heart disease patients from Chinese Han population (128 with and 753 without AF) were recruited in this study. The genotypes of the MMP2-1306C>T and -735C>T polymorphisms and TIMP-2 -418G>C polymorphisms were determined using PCR based method. The plasma concentration of TIMP-2 was measured by enzyme-linked immunosorbent assay in a subgroup with 81 patients. RESULTS: Both genotype distribution and allele frequency of the TIMP-2 -418G>C polymorphism were significantly different between the AF and control group (P=0.005 and P=0.001, respectively). The C allele carriers (GC+CC) had a significantly increased risk of AF compared with the GG homozygotes (odds ratio,1.77, 95% CI 1.21-2.92, P=0.009) in a logistic regression model after adjustment for age, left atrial dimension, left ventricular mass index, and antihypertensive drugs. The C allele carriers also had reduced levels of plasma TIMP-2 levels compared with GG homozygotes in both AF patients and control subjects. No relationship was found in this cohort between the presence of the MMP-2 -1306C>T and -735C>T polymorphism and AF. CONCLUSIONS: The TIMP-2 -418G>C polymorphism is significantly associated with an increased susceptibility to AF in Chinese Han patients with hypertensive heart disease. The -418C allele, which is associated with a decreased expression of TIMP-2, might be a genetic risk for the development of AF in this cohort.

Functional polymorphisms in ACE and CYP11B2 genes and atrial fibrillation in patients with hypertensive heart disease.

BACKGROUND: The activated renin-angiotensin-aldosterone system has been reported to play an important role in the pathogenesis of atrial fibrillation (AF). We hypothesized that functional genetic variations of angiotensin-converting enzyme (ACE) and CYP11B2 genes may influence the susceptibility to AF in patients with hypertensive heart disease. METHODS: The I/D polymorphism of ACE was detected by polymerase chain reaction (PCR), and the -344C/T polymorphism of the CYP11B2 gene was detected using PCR and subsequent cleavage by HaeIII restriction endonuclease. RESULTS: The overall distribution of ACE I/D genotypes in patients with and without AF was significantly different (p=0.001). The frequency of the DD genotype was significantly higher in patients with AF than in patients without AF (20.6% vs. 8.1%, OR 2.94, 95% CI 1.64-5.26, p<0.001). The frequency of the D allele was significantly higher in the AF group than in the non-AF group (p=0.001). After adjustment for age and left atrial dimension, multivariable analysis showed that the DD genotype of the ACE gene was an independent risk factor for AF in patients with hypertensive heart disease. No relationship between -344 C/T CYP11B2 polymorphism and AF was found in this cohort. CONCLUSIONS: Our study suggests that ACE I/D polymorphism is associated with AF and the DD genotype may be an independent predictive factor for AF in patients with hypertensive heart disease.

Neural network learning algorithms for tracking minor subspace in high-dimensional data stream.

A novel random-gradient-based algorithm is developed for online tracking the minor component (MC) associated with the smallest eigenvalue of the autocorrelation matrix of the input vector sequence. The five available learning algorithms for tracking one MC are extended to those for tracking multiple MCs or the minor subspace (MS). In order to overcome the dynamical divergence properties of some available random-gradient-based algorithms, we propose a modification of the Oja-type algorithms, called OJAm, which can work satisfactorily. The averaging differential equation and the energy function associated with the OJAm are given. It is shown that the averaging differential equation will globally asymptotically converge to an invariance set. The corresponding energy or Lyapunov functions exhibit a unique global minimum attained if and only if its state matrices span the MS of the autocorrelation matrix of a vector data stream. The other stationary points are saddle (unstable) points. The globally convergence of OJAm is also studied. The OJAm provides an efficient online learning for tracking the MS. It can track an orthonormal basis of the MS while the other five available algorithms cannot track any orthonormal basis of the MS. The performances of the relative algorithms are shown via computer simulations.