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Background and Aims Spontaneous bacterial peritonitis (SBP) is one of the leading causes of death in patients with liver cirrhosis. We aimed to establish a prognostic model to evaluate the 1-year survival of cirrhosis patients after the first episode of SBP. Methods A prognostic model was developed based on a retrospective derivation cohort of 309 cirrhosis patients with first-ever SBP and was validated in a separate validation cohort of 141 patients. We used Uno’s concordance, calibration curve, and decision curve (DCA) analysis to evaluate the discrimination, calibration, and clinical net benefit of the model. Results A total of 59 (19.1%) patients in the derivation cohort and 42 (29.8%) patients in the validation cohort died over the course of 1 year. A prognostic model in nomogram form was developed with predictors including age [hazard ratio (HR): 1.25; 95% confidence interval (CI): 0.92–1.71], total serum bilirubin (HR: 1.66; 95% CI: 1.28–2.14), serum sodium (HR: 0.94; 95% CI: 0.90–0.98), history of hypertension (HR: 2.52; 95% CI: 1.44–4.41) and hepatic encephalopathy (HR: 2.06; 95% CI: 1.13–3.73). The nomogram had a higher concordance (0.79) compared with the model end-stage liver disease (0.67) or Child-Turcotte-Pugh (0.71) score. The nomogram also showed acceptable calibration (calibration slope, 1.12; Bier score, 0.15±0.21) and optimal clinical net benefit in the validation cohort. Conclusions This prediction model developed based on characteristics of first-ever SBP patients may benefit the prediction of patients’ 1-year survival.

Four cupric cluster based magnetic coordination polymers Cu8O(tta)12(ClO4)2⋅2H2O (1), [Cu5(tta)9]Cl (2), Cu3(OH)2Cl (tta)3 (3) and Cu3(tta)4Cl2 (4) (Htta = 1-H-tetrazole) have been prepared by the same starting materials of cupric chloride and tetrazole, with the only difference of reaction temperature and pH value tuned by inorganic perchloric acid, among which complexes 2 and 3 are initially reported. Notoriously, high temperature can promote the reducing tendency of Cu(II)-to-Cu(I) in Cu/tetrazole system, whereas reducing tendency was prohibited by pH value control using perchloric acid in this work to generate cupric tetrazolate coordination polymers. Furthermore, different cupric cluster secondary building units (SBUs) such as planar Cu4O, trigonal prism-like Cu8, linear Cu3(OH)2 and Cu3Cl2 as well as the overall framework topologies such as bcu, asc and bct were observed. The bonding nature of chloride shows regular variation from free anion, dative Cu⋯Cl bond and normal Cu–Cl coordination bond due to Jahn-Teller effect of Cu(II) ions.

With the rapid development of automobile industry and the accelerated process of urbanization, pollution caused by automobile exhaust had become one of the major sources of urban environment and atmospheric environment pollution. According to the automobile exhaust emission characteristics in this paper, the generation mechanism of major automobile exhaust pollutants which were suspended solid particles, carbon monoxide nitrogen oxides and hydrocarbons, were described, as well as emission control measures with environmental materials.

The traditional SEPIC converter switch is turned on for a long time and as time is short, resulting in loss and temperature rise is too large, etc, isolated SEPIC converter is proposed to analyze the working principle and the transmission efficiency. And the circuit is improved, designed clamp isolated converters, photovoltaic cells based on the characteristics of the circuit used in photovoltaic power generation MPPT (Maximum Power Point Tracking, referred to as MPPT) system. Simulation and experimental results verify its feasibility.

Because the output voltage and current of wind and solar power generation system are nonlinear, PID control has its control of energy storage system to reach the best results. This paper presents a fuzzy control system, which intelligent controlling its energy storage system, and details fuzzy control design process, using Infineon’s XC164 microcontroller for the control of the company's core, designing a wind and solar energy storage system, for fast charging, reliable intelligent control system.

It is important implications to understand correctly hydrogeology characteristics of aquifers and aquifuge in unconsolidated layers bottom for reasonable retainment of safe coal rock pillar. In this paper, by means of drilling data statistics, X-ray diffraction(XRD), soil test and pumping test, aquifers and aquifuge Hydrogeology characteristics in Cenozoic unconsolidated layers bottom of SunTuan coal mine 102 mining area are comprehensively analyzed. It draw the conclusion that impermeability of “3rd-aquifuge” is good; “4th-aquifer” is weak permeable aquifer. These results have guiding significance for extending the upper extraction limit of mining area, and provide important protection for green exploitation of shallow seam covered with thin bedrock.

The no.10 coal seam in the first mining area of Yuandian coal mine lies in “Taiyuan Group limestone” aquifer with rich water, the underlying limestone water is an important danger for mine water-filling. To ensure the safety of mining, it is necessary to study and analyze the mining conditions. On this basis, with the design of targeted prevention and treatment of water, we achieve the purpose of safe mining.

In recent years, landfill and incineration of waste is considered a new mercury pollution, which is paid widespread attention by domestic and foreign scientists. This paper studies mercury pollution Characteristics in the soil around Landfill taking landfill in Huainan City for an example and using AMA 254 Advanced Mercury Analyzer produced by US LECO Company. The result shows that: mercury content distribution in surface soil around landfill has the certain laws: S50(0.0411ppm)> S20(0.0345)>S100(0.0257), and the distribution of surface soil in different directions is as follows: WS II (0.0525ppm) >W(0.0441ppm)>WS I (0.0255ppm)>ES(0.0218ppm); The vertical distribution is as follows: mercury content in the southeast increased with increasing depth and the rest direction decreases with depth increasing.

Lithological characteristics, mineral composition, physical properties of water and physical and mechanical properties, weathering zone distribution and other factors of bedrock weathering zone in coal-seam roof determine the strength of its watertight performance, while its performance has a direct impact on impermeable overlying loose surface water aquifers as well as the possible collapse into the roadway. Therefore, we can prove and correctly evaluate the hydro geological conditions of bedrock weathering zone in the working surface, which has an important practical significance on reasonable safe mining coal rock pillar height and upper limit of mining, increasing the recovery rate of coal resources, fully developing and utilizing coal resources. And it provides a reliable basis for mine to achieve a sustained normal safety production.

This paper investigates the stability of a class of delayed neural networks with impulses. By means of Lyapunov direct method, the new sufficient conditions for exponential stability of the systems are derived.

In order to improve the performance of fault diagnosis systems based on a wavelet neural network, according to the frequency domain characteristics of the vibration signals of the ball bearings, a diagnosis system which based on the wavelet packet analysis for picking up character and improved wavelet neural network is proposed, the conception of wavelet packet analysis and the basic idea of fault diagnosis of wavelet and neural network are also involved. The energy distributing of each frequency segment which is decomposed by wavelet packet is treated as the eigenvector and input the IWNN, and the recognition of the fault models of the ball bearings is completed by using improved wavelet neural network. The result of test and theory shows that circuit fault can be detected and located quickly by using this method and the training speed of wavelet neural network is dramatically accelerated.

AIM: To determine the dynamic changes in the expression of matrix metalloproteinases (MMPs) and the endogenous tissue inhibitors of MMPs inhibitors (TIMPs) during hepatic fibrosis induced by alcohol. METHODS: Male Sprague-Dawley rats were randomly divided into normal, 4 d, 2 wk, 4 wk, 9 wk and 11 wk groups, and the model rats were fed with a mixture of alcohol by gastric infusion at the designed time, respectively, then decollated and their livers were harvested for the examination of MMP-2, MMP-3, MMP-9, MMP-13, TIMP-1 and TIMP-2 by immunoh-istochemistry, zymograghy and Western blotting, respectively. RESULTS: Normal rats had moderate expression of MMP-2, which was decreased in the model rats except in the 11 wk group, where MMP-2 expression slightly increased. MMP-3 had the similar changing pattern to MMP-2 despite weaker expression. MMP-9 expression decreased in the 4 d and 2 wk groups, rose in the 4 wk group, decreased again in the 9 wk group and returned to normal levels in the 11 wk group. MMP-13 expression decreased in the 4 d and 2 wk groups, and returned to normal levels in the 4 wk, 9 wk and 11 wk groups. TIMP-1 expression decreased in the 4 d and 2 wk groups, but sharply increased in the 4 wk group and sustained at a high level even after modeling was stopped for 2 wk. In normal rats TIMP-2 expression was strong. However, it decreased as soon as modeling began, and then gradually rose, but remained to a level lower than that in normal rats even after modeling was stopped for 2 wk. CONCLUSION: MMP-2 may not always expresses at a high level during hepatic fibrosis. MMP-13 and MMP-3 are acutely affected by TIMP-1. In this model TIMP-1 is the most powerful factor imposed on capillarization and peri-sinusoidal fibrosis. TIMP-2 is the most effective regulator on the metabolism of type IV collagen located in the basement of sinus.

AIM: To investigate the dynamic changes of capillarization and peri-sinusoid fibrosis in an alcoholic liver disease model induced by a new method. METHODS: Male SD rats were randomly divided into 6 groups, namely normal, 4 d, 2 w, 4 w, 9 w and 11 w groups. The animals were fed with a mixture of alcohol for designated days and then decollated, and their livers were harvested to examine the pathological changes of hepatocytes, hepatic stellate cells, sinusoidal endothelial cells, sinusoid, peri-sinusoid. The generation of three kinds of extra cellular matrix was also observed. RESULTS: The injury of hepatocytes became severer as modeling going on. Under electronic microscope, fatty vesicles and swollen mitochondria in hepatocytes, activated hepatic stellate cells with fibrils could been seen near or around it. Fenestrae of sinusoidal endothelial cells were decreased or disappeared, sinusoidal basement was formed. Under light microscopy typical peri-sinusoid fibrosis, gridding-like fibrosis, broaden portal areas, hepatocyte’s fatty and balloon denaturation, iron sediment, dot necrosis, congregated lymphatic cells and leukocytes were observed. Type I collagen showed an increasing trend as modeling going on, slightly recovered when modeling stopped for 2 weeks. Meanwhile, type IV collagen decreased rapidly when modeling began and recovered after modeling stopped for 2 weeks. Laminin increased as soon as modeling began and did not recover when modeling stopped for 2 weeks. CONCLUSION: The pathological changes of the model were similar to that of human ALD, but mild in degree. It had typical peri-sinusoid fibrosis, however, capillarization seemed to be instable. It may be related with the reduction of type IV collagen in the basement of sinusoid during modeling.