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This paper is concerned with the problem of stabilization for neutral stochastic delay differential equations by feedback control based on discrete-time state observations. Firstly, sufficient conditions that ensure the mean-square exponential stability of the controlled system are established. Then the linear matrix inequalities (LMIs) approach is employed to design the discrete-time feedback controller. Finally, an illustrative example is presented to show the effectiveness of the proposed results.

A new selective fluorescent chemosensor based on rhodamine 6G derivative ( R1 ) has been designed and synthesized, which displayed highly selective and sensitive detecting for lead ion in aqueous solution. Sensor R1 was selective toward Pb 2+ ion by a light yellow to pink change for the visual detection of Pb 2+ ion. The fluorescence recognition processes of Pb 2+ was based on a binding induced ring-opening from the spirolactam (nonfluorescent) to acyclic xanthenes (fluorescent). Sensor R1 was excited with a 1:1 binding ratio and the linear response in the range of 1.0 × 10 −8 –1.0 × 10 −5 mol L −1 with the limit of detection of 2.7 × 10 −9 mol L −1 (3σ/slope).

Recently, Mao [1] proposed a kind of feedback control based on discrete time state observations to stabilize continuous-time hybrid stochastic systems in mean-square sense. We find that the feedback control there still depends on the continuous-time observations of the mode. However, it usually costs to identify the current mode of the system in practice. So we can further improve the control to reduce the control cost by identifying the mode at discrete times when we make observations for the state. In this paper, we aim to design such a type of feedback controls based on the discrete-time observations of both state and mode to stabilize the given unstable hybrid stochastic differential equations (SDEs) in the sense of mean-square exponential stability. Moreover, a numerical example is given to illustrate our results.

The necessity and feasibility of antiviral therapy in patients with liver cirrhosis have caught much attention. By summarizing the relevant guidelines/consensus statements and evidence-based medicine data in recent years, the advances in indications, strategies, drug options, and benefit/risk in antiviral therapy for hepatitis B virus (HBV)- and hepatitis C virus (HCV)-related cirrhosis are reviewed. The data reveal that for both HBV- and HCV-related cirrhosis, successful treatment may suppress viral replication, improve patients′ conditions, delay disease progression, prolong survival, reduce complications, and create better conditions for surgical and minimally invasive operations for hepatocellular carcinoma. Because of the good safety of nucleos(t)ide analogues (NA), it is recommended that patients with HBV-related cirrhosis (including those in decompensation stage and with complications) should receive NA as soon as possible. As interferon may cause many adverse reactions, antiviral therapy for HCV-related cirrhosis becomes more difficult than that for HBV-related cirrhosis. Careful selection of indications is necessary. Standardization of the strategies for antiviral therapy is important in the treatment of liver cirrhosis.

Soil water holding capacity is the key index of water conservation capacity of ecosystems and vital parameter of ecological service function in Nature Reserve.Four typical ecosystems including forest,shrub,bamboo,and grassland were selected in the study area of Wuyunjie Nature Reserve(WNR) of Hunan Province and soil physical properties and water holding capacity were studied through field investigation,soil sampling,and laboratory analysis.The results showed that the four typical vegetation-covered lands had greater soil organic matter content(76 g/kg),lower bulk density(0.85 g/cm3),and higher soil aggregate stability(stable aggregate(5 mm in diameter) contents ranging from 22.7% to 52.3%) in the surface soil layer(0—20cm) than the local farmland,suggesting that soil structural development was generally better in the reserve area.Soil macroporosity and saturated hydraulic conductivity(Ks) in forest and bamboo ecosystems were greater than those in shrub and grassland ecosystems,which were beneficial to the rainfall transfer to groundwater.However,soil capillary porosity in shrub and grassland ecosystems were higher,indicating that more soil available water could be reserved.The gravimetric soil water holding capacity(WHCg) in the 0—40 cm soil layer under four typical ecosystems in WNR changed in the following order: forest(83.5 mm) bamboo(79.2 mm) shrub(66.9 mm) grassland(43.8 mm).However,soil available water holding capacity(WHCa) were the following: grassland(128.7 mm) shrub(111.6 mm) forest(95.9 mm) bamboo(83.9 mm).On the basis of verifying the definition of total water capacity(0 MPa),WHCg(0—0.01 MPa),WHCa(0.01—1.5 MPa),and unavailable water capacity(1.5 MPa),we recommended that WHCg and WHCa could be used to measure soil water holding capacity of ecosystems.WHCg could be used to assess the capability of recharging groundwater and adjusting river flow,while WHCa could be used to assess the potential of soil water holding capability in the ecosystems.These indexes all could be measured through soil water characteristic curves.The close relationships between soil water holding capability and water storage capacity demonstrated that,vegetation type and soil structure were of importance in water sources reserve.Forest and bamboo ecosystems,characterized by the well-developed spatial structures,had stronger capability in recharging groundwater and adjusting river flows.However,shrub and grassland,which had relatively undeveloped spatial structure,could reserve more soil available water in the ecosystems.All these were associated with the changes in soil structures.Therefore,the conservation of diverse ecosystems has crucial ecological significance in the diversity conservation of habitats and eco-environments in the WNR.

Background/aims Peroxisome proliferator-activated receptors-gamma (PPAR-gamma) and its co-activator-1alpha (PGC-1alpha) are involved in the regulation of lipid and glucose metabolisms. This study aimed to investigate the genetic polymorphisms of PPAR-gamma and PGC-1alpha in Chinese people and their influence on plasma adiponectin levels and non-alcoholic fatty liver disease (NAFLD) susceptibility. Methods Ninety-six patients with NAFLD and 96 healthy controls were included. The single nucleotide polymorphisms (SNPs) of C161T PPAR-gammaand Gly482Ser PGC-1alpha genes were analysed by polymerase chain reaction and restriction fragment length polymorphism. Result The CC, CT and TT genotypic distributions of the NAFLD group were significantly different from those of controls (55.2, 39.6, 5.2 vs. 74.0, 25.0, 1.0%; P=0.015). The allelic frequencies of C and T were also different between the two groups (P=0.004). As for the PGC-1alpha gene, there was no difference of the genotypic and allelic frequencies between the two groups (P>0.05). In NAFLD patients, the plasma adiponectin concentrations were lower in the PPAR-gamma CT/TT genotypes compared with those in the CC genotype group (3.0+/-0.6 vs. 4.3+/-0.9, P=0.02). Multivariate logistic regression analysis showed that CT/TT genotypes of PPAR-gamma, TG, waist hip ratio, hypoadiponectinaemia and homoeostasis model assessment (HOMA)-IR were the risk factors for NAFLD. Conclusion SNPs in the PPAR-gamma, but not PGC-1alpha, gene are associated with NAFLD susceptibility possibly through the adiponectin pathway.

OBJECTIVE: To investigate the role of psychological factors in functional dyspepsia (FD) and the effects of antidepressant drugs on FD. METHODS: The psychological status of 24 FD patients and 24 healthy people was analyzed using the Hamilton Rating Scale for Depression (HRSD), the Hamilton Anxiety Scale (HAS) and the Symptom Checklist 90 (SCL-90) scale. Antidepressants were used to treat FD patients for 8 weeks; 13 patients received Prozac, 11 patients received Seroxat. Psychometric analysis was carried out before and after treatment. RESULTS: There were significant differences in somatic and psychometric scores on the HAS and SCL-90 scales in the two groups (P < 0.001). The scores of the FD patients improved significantly after 8 weeks of treatment (P < 0.001). CONCLUSIONS: Psychological factors played a role in the etiology of FD. The patients commonly had depression or anxiety. Antidepressants were effective in the treatment of FD for improving both somatic and psychological symptoms.