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Parabens are widely employed in toothpaste, cosmetics, textiles, beverages, and preservatives, causing a serious environmental concern because they are endocrine-disrupting compounds (EDCs). As one of the highly reactive oxidants, ozone has a great effect on EDC removal. To understand the degradation and transformation of parabens in the aquatic environment and their toxicity to aquatic organisms, the degradation reaction of parabens initiated by O3 was studied meticulously using quantum chemical calculations. The degradation process includes multiple initial reaction channels and consequent degradation pathways of the Criegee intermediates. Through thermodynamic data, the rate constants were computed using the transition state theory (TST). At a temperature of 298 K and a pressure of 1 atm, the calculated rate constants were 3.92 and 3.94 M-1 s-1 for methylparaben (MPB) and ethylparaben (EPB), respectively. The rate constants increased as the temperature increased or as the length of the alkyl chain on the benzene ring increased. Through the ecotoxicity assessment procedure, the ecotoxicity of parabens and the products in the degradation process can be assessed. Most degradation byproducts are either less toxic or nontoxic. Some byproducts are still harmful, such as oxalaldehyde (P2) and ethyl 2,3-dioxopropanoate (P10). Furthermore, the ecological toxicity of parabens increased with augmentation of the alkyl chain on the benzene ring. The effect of the alkyl chain length on the benzene ring in the compound cannot be ignored.

The occurrence and development of diabetes seriously threaten the health of patients. Therefore, the mechanism exploration of diabetes is of great significance for more effective control of this disease. In this study, we aimed to investigate the regulatory mechanism of miR-139-5p and Notch signaling pathway on liver damage and oxidative stress in diabetic mice. The mouse model of diabetes was established, and the mice were divided into normal group, model group, negative control (NC) group, miR-139-5p mimic group, miR-139-5p inhibitor group, DAPT group, and miR-139-5p inhibitor + DAPT group. The mRNA expressions of miR-139-5p, Notch1, Jagged1, and NICD1, and the protein expressions of Notch1, Jagged1, and NICD1 were detected. In addition, HepG2 cells were cultured for high glucose induction, and cell cycle distribution and apoptosis were detected by flow cytometry. The results showed that the body weights of mice in the model, NC, miR-139-5p mimic, miR-139-5p inhibitor, DAPT, and miR-139-5p inhibitor + DAPT groups were all lower than that in the normal group. Co-localization of miR-139-5p and Notch1 was observed in the fluorescence in situ hybridization assay, and miR-139-5p was found to negatively regulate Notch1. Furthermore, reduced blood glucose level and inhibited liver oxidative stress were observed in mice with miR-139-5p overexpression or DAPT treatment. DAPT treatment reversed the increase of blood glucose level and oxidative stress injury caused by miR-139-5p silencing. In conclusion, up-regulation of miR-139-5p expression can protect liver tissue from oxidative stress injury in diabetic mice, and its mechanism may be related to the inhibition of Notch signaling pathway.

Hubei Province is one of the endemic regions with severe schistosomiasis in China. To eliminate schistosomiasis in lake and marshland regions, this study detected hotspots of schistosomiasis cases both spatially and spatiotemporally on the basis of spatial autocorrelation; clustering and outlier, purely spatial and spatiotemporal cluster analyses at the village level from 2013 to 2017 in Hubei Province. The number of cases confirmed positive by an immunodiagnostic test and etiological diagnosis and advanced schistosomiasis cases dramatically declined during the study period. Significant global spatial autocorrelation of schistosomiasis patients was found at the village level in the whole province in 5 years. Clustering and outlier analysis showed that most HH villages were mainly concentrated along the Yangtze River, especially in Jianghan Plain. Spatial and spatiotemporal cluster analyses showed that significant clusters of the schistosomiasis cases were detected at the village level. In general, space and spatiotemporal clustering of schistosomiasis cases at the village level demonstrated a downward trend from 2013 from 2017 in Hubei Province. High-risk regions included Jianghan Plain along the middle reach of Yangtze River and Yangxin County in the lower reaches of the Yangtze River in Hubei Province. To eliminate schistosomiasis, precise control and management of schistosomiasis cases should be strictly implemented. Moreover, comprehensive prevention and control measures should be continuously strengthened in these regions.

As one of the main components of combustion of tobacco products occurs (CARB), crotonaldehyde has an acute toxicity and widely exists in the atmosphere, which is harmful to human health. The removal efficiency of VOCs by ozonation can reach 80–90%. Based on the theory of quantum chemistry, the degradation mechanism, kinetics and toxicity of crotonaldehyde by ozonation in gas phase and heterogeneous phase were studied. Ozone was added to the olefins unsaturated double bond to form a five-membered ring primary ozonide, which was further fractured due to its unstable structure to form a Criegee intermediate and an aldehyde compound. The reaction rate constant of crotonaldehyde with ozone was 1.24 × 10−17 cm3 molecule−1 s−1 at 298 K and 1 atm, which was an order of magnitude higher than the experimental value. From toxicity assessment, it was found that the ozonation of crotonaldehyde is beneficial to the removal of toxicity. Mineral dust aerosol exists in the atmosphere in large quantities, and SiO2 is the most abundant component. VOCs are transformed into particle state on their surface through homogeneous nucleation and heterogeneous nucleation. Referring to the crystal structure of SiO2, five hydroxylated silica oligomer cluster structures were simulated and the adsorption configurations of crotonaldehyde on their surface were simulated. The adsorption of crotonaldehyde on the surface of the clusters was achieved by forming hydrogen bonds and had good adsorption effects. The adsorption of hydroxylated silica oligomer clusters didn't change the ozonation mechanism of crotonldehyde, but had a certain effect on the reaction rate.

Sulfometuron methyl (SM) is a widely used herbicide and thus leading to accumulation in the environment. The toxicity assessments of SM in model organisms are currently rare. In the present study, zebrafish were utilized for evaluating the detrimental effects of SM in aquatic vertebrates. Zebrafish embryos were exposed to 0, 10, 20, and 40 mg/L SM from 5.5 to 72 h post-fertilization (hpf), respectively. Consequently, SM exposure resulted in increasing the mortality rate and reducing hatching rate in larval zebrafish at 10, 20, and 40 mg/L SM-treated groups. The reduced numbers of immune cells (neutrophils and macrophages) were observed after SM exposure by a dose-dependent manner. The inflammatory responses (TLR4, MYD88, IL-1β, IL-6, IL-8, IFN-γ, IL-10, and TGF-β) were measured to estimate immune responses. Anti-inflammatory factors (IL-10 and TGF-β) were down-regulated in all the treated groups and significantly altered at 40 mg/L exposure group. Additionally, behavioral tests suggested that SM treatment significantly increased the total distance, average speed, and maximum acceleration of larval zebrafish during light-dark transition and subsequently enzymology test displayed the same trend to locomotor behaviors. The content significantly increased in oxidative stress, as reflected in ROS level in all the treated groups. The numbers of cell apoptosis were significantly increased at 20, and 40 mg/L and the highest concentration group induced the substantial increment (P

Pesticides occur in the environment as mixtures, yet the joint toxicity of pesticide mixtures remains largely under-explored and is usually overlooked in ecological risk assessment. In the current study, joint toxicity of a neonicotinoid insecticide (imidacloprid, IMI) and a strobilurin fungicide (azoxystrobin, AZO) was investigated with Chironomus dilutus over a wide range of concentrations and at different effect levels (organism, cell, and gene levels). The two pesticides, both individually and in combination, were found to induce oxidative stress and cause lethality in C. dilutus. Median lethal concentrations for IMI and AZO were 3.98 ± 1.17 and 52.9 ± 1.1 μg/L, respectively. Mixtures of the two pesticides presented synergetic effects at environmentally relevant concentrations whilst antagonistic effects at high concentrations, showing concentration-dependent joint toxicity. Investigation on the expressions of 12 genes (cyt b, coi, cox1, cyp4, cyp12m1, cyp9au1, cyp6fv1, cyp315, gst, Zn/Cu-sod, Mn-sod, and cat) revealed that the two pesticides impaired mitochondrial respiration, detoxification, and antioxidant system of C. dilutus, and the joint effects of the two pesticides were likely due to an interplay between their respective influences on these physiological processes. Collectively, the synergistic effects of the two pesticides at environmentally relevant concentrations highlight the importance to incorporate combined toxicity studies into ecological risk assessment of pesticides.

The pharmaceutical and personal care products (PPCPs) in aquatic environment have aroused more interest recently. Many of them are hard to degrade by the typical biological treatments. Diclofenac (DCF), as a significant anti-inflammatory drug, is a typical PPCP and widely existed in water environment. It is reported that DCF has adverse effects on aquatic organisms. This work aims to investigate the mechanism, kinetics and ecotoxicity assessment of DCF transformation initiated by O3 in aqueous solution, and provide a solution to the degradation of DCF. The O3-initiated oxidative degradations of DCF were performed by quantum chemical calculations, including thirteen primary reaction pathways and subsequent reactions of the Criegee intermediates with H2O, NO and O3. Based on the thermodynamic data, the kinetic parameters were calculated by the transition state theory (TST). The total reaction rate constant of DCF initiated by O3 is 2.57 × 103 M−1 s−1 at 298 K and 1 atm. The results show that the reaction rate constants have a good correlation with temperature. The acute and chronic toxicities of DCF and its degradation products were evaluated at three different trophic levels by the ECOSAR program. Most products are converted into less toxic or harmless products. Oxalaldehyde (P3) and N-(2,6-dichlorophenyl)-2-oxoacetamide (P6) are still harmful to the three aquatic organisms, which should be paid more attention in the future.

Neonicotinoid insecticides have posed a great threat to non-target organisms, yet the mechanisms underlying their toxicity are not well characterized. Major modes of action (MoAs) of imidacloprid were analyzed in an aquatic insect Chironomus dilutus. Lethal and sublethal outcomes were assessed in the midges after 96-h exposure to imidacloprid. Global transcriptomic profiles were determined using de novo RNA-sequencing to more holistically identify toxicity pathways. Transcriptional 10% biological potency values derived from ranked KEGG pathways and GO terms were 0.02 (0.01–0.08) (mean (95% confidence interval) and 0.05 (0.04–0.06) μg L−1, respectively, which were more sensitive than those from phenotypic traits (10% lethal concentration: 0.44 (0.23–0.79) μg L−1; 10% burrowing behavior concentration: 0.30 (0.22–0.43) μg L−1). Major MoAs of imidacloprid in aquatic species were identified as follows: the activation of nicotinic acetylcholine receptors (nAChRs) induced by imidacloprid impaired organisms’ nerve system through calcium ion homeostasis imbalance and mitochondrial dysfunction, which posed oxidative stress and DNA damage and eventually caused death of organisms. The current investigation highlighted that imidacloprid affected C. dilutus at environmentally relevant concentrations, and elucidated toxicity pathways derived from gene alteration to individual outcomes, calling for more attention to toxicity of neonicotinoids to aquatic organisms.

ObjectiveTo analyze the clinical manifestations, laboratory indexes, disease activity, and pathological types of lupus nephritis (LN) in adult patients.MethodsWe retrospectively analyzed the clinical manifestations, laboratory indexes, and pathological classifications of 156 adult patients first diagnosed with LN between July 2013 and November 2017. Patients were categorized according to the following criteria: active or inactive LN, LN with or without renal damage, and mild or severe LN.ResultsImmunoglobulin G and A levels, 24-hour proteinuria, and anti-dsDNA, anti-Sm, and anti-ribosomal P protein antibody positivity rates were all significantly increased in patients with active LN compared with inactive LN. Anti-dsDNA antibody positivity and 24-hour proteinuria were significantly increased, whereas hemoglobin, serum albumin, and C3 and C4 levels were significantly decreased in patients with LN and renal damage compared with those without renal damage. Anti-dsDNA and anti-Sm antibody positivity rates and 24-hour proteinuria were significantly increased, while hemoglobin, serum albumin, C3 and C4 levels, and estimated glomerular filtration rate were significantly decreased in patients with severe LN compared with patients with mild LN.ConclusionsLN can display various clinical manifestations, laboratory indexes, levels of disease activity, and pathological types in adult patients.

In this paper, the gas-phase and heterogeneous reactions of acrolein with ozone were studied comprehensively and deeply. Acrolein is one of the simplest unsaturated aldehydes found widely in the fuel combustion and industrial emissions. Mineral particles produced by frequent sandstorms have important effects on the tropospheric chemistry and the climate change. The content of silica in clay minerals is rich, thus three kinds of clusters (the monomeric model Si(OH)4, the linear model Si3O2(OH)8 and the cyclic hexamer model Si6O6(OH)12) were selected for the heterogeneous study. The reaction rate constant of acrolein with ozone at 298 K and 1 atm was 7.46 × 10−18 cm3 molecule−1 s−1, which was in agreement with the experimental value. SiO2 clusters interacted with acrolein via the hydrogen bonds and had good adsorption properties. The hydrogen bond between the oxygen of aldehyde group on acrolein and the hydrogen of silica surface was stronger and the adsorption energy was greater. The adsorption of silanol groups did not change the ozonation mechanism of acrolein, but had effects on the reaction rate. Among them, three silanol groups acted as positive catalysts. The kinetic data within the temperature range of 216.65–288.15 K corresponding to the height of the troposphere at 0–11 km showed that the rate constant of O3-initiated reaction of acrolein is positively correlated with the temperature. In addition, we also studied the reaction mechanism and kinetic of the Criegee intermediates reacting with atmospheric small molecules and isomerization process in gas-phase and heterogeneous processes.

Dioxins and dioxin-like compounds (DLCs) are potent toxicants to most vertebrates. Sensitivities to DLCs vary among species. In the present study, the sensitivities of avian species (chicken [Gallus gallus], ring-necked pheasant [Phasianus colchicus], and Japanese quail [Coturnix japonica]) to some polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) were determined by using species-specific, in vitro, transactivation assays based on a luciferase reporter gene under control of species-specific aryl hydrocarbon receptors. In ring-necked pheasant and Japanese quail, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was not the most potent inducer of toxic effects. Especially for Japanese quail, the relative potency values of most of 9 PCDD/Fs tested were greater than for TCDD. The rank order of avian species sensitivities to DLCs was chicken > ring-necked pheasant > Japanese quail. Effects of binary mixtures of TCDD, 2,3,7,8-tetrachlorodibenzofuran, and 2,3,4,7,8-pentachlorodibenzofuran were strictly additive. Moreover, we also found that the primary DLCs that were responsible for most of the potency of the DLC mixtures can be deduced by using ordination in a multidimensional space defined by the avian species sensitivities. Overall, the relative potency and the species sensitivities of these chemicals could guide risk assessments to wild species when exposure to mixtures of DLCs in the environment.

A variety of chemicals are capable of provoking mitochondrial dysfunction and thereby contribute to metabolic disorder related effects in wildlife and human. For better identifying new mitochondrial toxicants and assessing mitochondria-related risk, an in-depth understanding of toxic mechanisms and biomarkers should be attained. In the current study, a representative mitotoxicant, azoxystrobin, was assessed for lethal and sublethal outcomes in Chironomus dilutus after 96-h exposure and the toxic mechanism was explored. Global transcriptomic profiles by RNA-sequencing revealed that ampk, acc1, atp2a, gsk3b, pi3k, fak, atr, chk1, and map3k5 were the key genes which involved in the toxic action of azoxystrobin and could serve as potential molecular biomarkers. A major network of common toxicity pathways was then developed for mitotoxicants towards aquatic insects. In particular, calcium ion-PI3K/AKT and cAMP-AMPK-lethality pathways were demonstrated, in addition to the well-known mitochondrial electron transfer-oxidative damage-apoptosis pathway. These analyses could help developing adverse outcome pathways that integrate toxicological information at various levels and support more effective risk assessment and management of mitotoxicants.

Long non-coding RNA-oncogene-induced senescence 1 (lncRNA-OIS1) is a novel lncRNA that is involved in oncogene-induced senescence, while its functionality in cervical squamous cell carcinoma is unknown. In the present study, 68 human papillomavirus (HPV)-positive and 22 HPV-negative patients with cervical squamous cell carcinoma were recruited. Additionally, 40 healthy females were employed as healthy controls. Tumor tissues and adjacent healthy tissues were collected from all patients with cervical squamous cell carcinoma, and blood samples were obtained. Expression of OIS1 was detected by reverse transcription-quantitative polymerase chain reaction. Receiver operating characteristic curve analysis was used to evaluate the diagnostic value of OIS1 for cervical squamous cell carcinoma. HPV-positive and HPV-negative cervical squamous cell carcinoma and normal cervical cell lines were used, and the effects of OIS1 or mitogen-activated protein kinase kinase kinase 4, (MTK-1) expression vector transfection on the proliferation of cell lines and MTK-1 expression were detected by CCK-8 assay and western blotting, respectively. It was established that a reduction in OIS1 expression level in tumor tissues was apparent only in HPV-positive patients. Serum levels of OIS1 were lower in HPV-positive patients compared with that in HPV-negative patients and healthy controls, and no significant differences were observed between HPV-negative patients and healthy controls. Serum levels of OIS1 were significantly associated with tumor size, but not distant tumor metastasis. OIS1 expression level was lower in HPV-positive cancer cell lines compared with that in HPV-negative cancer cell lines, while no significant differences were observed between HPV-positive and HPV-negative normal cell lines. OIS1 overexpression inhibited and MTK-1 overexpression promoted the proliferation of HPV-positive, but not HPV-negative cancer or normal cell lines. OIS1 transfection also decreased the expression of MTK-1 in HPV-positive cancer cell lines, but not in any of the other cell lines. Therefore, it was concluded that OIS1 inhibited HPV-positive, but not HPV-negative cervical squamous cell carcinoma by upregulating MTK-1.

OBJECTIVES: This study aims to investigate the positive detection rate and predictive value of autoantibodies, including anti-double stranded deoxyribonucleic acid (anti-dsDNA) antibodies, anti-histone antibodies (AHAs), anti-ribosomal (anti-Rib) P antibodies, anti-Smith (anti-Sm) antibodies, anti-U1 ribonucleoprotein (anti-U1RNP) antibodies, anti-Sjögren's syndrome type A antibodies and anti-Sjögren's syndrome type B antibodies, on organ damage in patients with systemic lupus erythematous (SLE). PATIENTS AND METHODS: A total of 225 patients with SLE (37 males, 188 females; mean age 37.4±15.9 years; range, 7 to 80 years) were evaluated retrospectively. Statistical analysis was performed to obtain the positive detection rate of autoantibodies and to investigate the predictive value. RESULTS: There were statistically significant differences of positive anti-dsDNA antibodies in renal damage, photosensitization, hematological abnormalities and serositis (p0.05). CONCLUSION: Autoantibody spectrum is an important serological basis for SLE diagnosis. There are differences in the autoantibodies distribution of SLE patients with different organ damage, suggesting a certain clinical value for prediction of organ damage in SLE.

Long noncoding RNAs (lncRNAs) are associated with tumor development and progression. LncRNA UCA1 (UCA1) recently has been reported to take part in cancer cell proliferation. However, the expression and underlying molecular mechanism of UCA1 in cervical cancer cell glycolysis is unclear. This study aimed to investigate the role of UCA1 in cervical cancer. In order to explore the role of UCA1 in cervical cancer, first, the expression levels of UCA1 in cervical cancer tissues were measured, and the results showed that UCA1 levels were higher in cancer tissues compared to matched adjacent normal tissues. The inhibition of UCA1 expression suppressed human cervical cancer cell proliferation and glycolysis. Additionally, our experimental results indicated that UCA1 could directly bind to miR-493-5p and regulate miR-493-5p expression in an inverse manner. Namely, UCA1 could reverse the inhibitory effect of miR-493-5p on cervical cancer cells’ proliferation and glycolysis. Moreover, we revealed that HK2 is a target gene of miR-493-5p through a Targetscan prediction. It was verified that miR-493-5p downregulated HK2 mRNA and protein levels using real time RT-PCR and Western blotting. In a summary, this study demonstrated that UCA1 functioned as an oncogene by UCA1/miR-493-5p/HK2 axis in cervical cancer.

Coupling polydimethylsiloxane (PDMS)-based equilibrium passive sampling with chemical and bioassay analysis, we assessed aryl hydrocarbon receptor (AhR)-mediated activity and contributing chemicals in sediment from Lake Tai Basin, Eastern China. The bioanalytical equivalent concentrations (BEQs) of AhR-active chemicals for the exhaustive (total burden) and PDMS extracts (bioavailable fractions) ranged from9.5-300 ng TCDD-EQ/ kgdry weight (dw) and0.096-2.2 ng TCDD-EQ/kgdw, respectively, which were of average levels compared to those reported elsewhere. The total concentrations of PAHs in sediment and PDMS were 17-4700 μg/kgdw and 0.61-10 μg/kgdw, respectively. The majority of the exhaustive extracts subject to acid treatment showed70% decline in AhR-mediated activity, suggesting the minor contribution by persistent AhR ligands. Targeted analysis of polycyclic aromatic hydrocarbons (PAHs) showed, however, that these chemicals contributed40% to the overall effect in both exhaustive and PDMS extracts, indicating the presence of other labile AhR ligands. The concentrations of PAHs and BEQs of the AhR-mediated activity attributed to these chemicals in the exhaustive extracts can be back calculated from those in the PDMS extracts via a general organic carbon-PDMS partition coefficient. Similar quantitative conversion between PDMS and aquatic organisms was also verified for aquatic organisms via the lipid-PDMS partition coefficient. Therefore, our study provided a first insight into the quantitative links between bulk chemical burdens in sediment, chemical bioavailability, bioaccumulation potential and resulting mixture effects, as an integral part of predictive environmental risk assessment of contaminated sediment.

To understand the influence of meteorological factors on Oncomelania density in natural condition and provide scientific evidence for the control of the spread of schistosomiasis and Oncomelania.Based on the Oncomelania survey data in spring and ground meteorological observation data of Qianjiang from 1990 to 2014, the first-order autoregressive analysis method was used for trend fitting and disassemble, and the correlation between the change rate of Oncomelania density and various meteorological factors in different periods were analyzed.The greatest influence of meteorological factors on Oncomelania density was temperature, followed by precipitation. The average minimum temperature in January and from December to February had predominant influence on Oncomelania density and frame occurrence rate of living Oncomelania (FORLO) respectively. The rise (fall) of average minimum temperature in January by 1 °C would lead to the increase (decrease) of Oncomelania density by 5.080%-6.710%; The rise (fall) of average minimum temperature from December to February by 1 °C would lead to the increase (decrease) of FORLO by 15.521%-15.928%. The period with the biggest influence of precipitation on Oncomelania density was from November to April, as the rainfall declined20%, drought might occur, which would cause the reduction of Oncomelania density. Sunshine from September to November had some correlations with the change of Oncomelania density and FORLO. Statistical regression models for the change of Oncomelania density, FORLO and meteorological factors based on correlation analysis were established respectively.Weed removal in Oncomelania areas before December is beneficial to reduce the surface temperature and soil moisture content, which would result in Oncomelania density reduction in some extent. It' s notable that the winter temperature is in rise in Hubei province along with global climate change, causing the Oncomelania density to increase, to which more attention should be paid.

The aim of study was to develop a stratified temporal spectral mixture analysis (STSMA) for cropland area estimation using MODIS time-series data to address the mixed pixel problem caused from coarse resolution. The proposed method used thematic map from MODIS classification as prior knowledge to determine the endmember set for each sub-region input into SMA model. The results indicated the STSMA method performing better in estimating the cropland land. RMSE s (from 0.25 to 010), R 2 s (from 0.65 to 0.89) and bias (0.02), used as three accuracy assessment parameters, and STSMA obtained higher overall accuracy in the entire study area, at individual pixel scale to 0.10 at 10×10 pixels scale, representing higher performance compared to the conventional spectral mixture analysis (SMA) method at each pixel scale. In single-season crop, dual-season crop, natural vegetation and non-vegetation dominated landscape, the similar success from STSMA is also achieved because the suitable endmember set was set for the proposed model to ensure the accuracy of cropland estimation to address the conventional SMA colinearity problem at some degree.

The corrosion inhibition of iron in 0.5 M H2SO4 solutions by alkyl quaternary ammonium halides (AQAH) inhibitors has been studied by potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) measurements. The correlation between inhibition efficiency and molecular structure of the AQAH compounds is investigated. The results show that besides the concentration, the structure of alkyl groups and the type of halide ions of these AQAH inhibitors greatly influence the inhibition efficiency. Data obtained from EIS measurements are analyzed to model the corrosion inhibition process through appropriate equivalent circuit models.

Platinum dispersed in polyaniline film is a better catalyst than bulk platinum for methanol electrooxidation in sulfuric acid solution. The effect of deposition modes of platinum particles on their electrocatalytic activity has been studied. Several electrodeposition methods, including constant potential, cyclic potential and double potential step, have been applied to characterize the performance of different electrodeposition modes. Besides the variation of the electrodeposition methods, rotating disk electrode technique is applied to disperse Pt particles under the control of convection–diffusion condition. The results show that the enhanced electrocatalytic activity may be due to the dispersion of Pt particles in the polyaniline film matrix and the synergistic effects between the dispersed Pt particles and the polyaniline film. Variables related to reaction kinetics, such as mass transport of species, concentration of methanol and acidity of solution, are investigated and reaction mechanism for methanol oxidation is discussed.

The composite electrode of platinum-modified polyaniline film is formed in 0.5 M H 2 SO 4 + 3 mM H 2 PtCl 6 solution by cyclic potential or constant potential deposition of platinum particles in polyaniline film. To make a comparison, the polyaniline film with the same initial thickness and structure is also treated with the cyclic potential or constant potential polarization in 0.5 M H 2 SO 4 solution. The electrochemical impedance spectroscopy (EIS) of the composite electrode of platinum-modified polyaniline film is studied in sulfuric acid solution and compared with the EIS of the polyaniline film without platinum dispersion. The results show that the different modes of potential polarization affect greatly the nature and distribution of the platinum particles, instead of the structure of the polyaniline film (matrix). The electrode reaction kinetics and mass transport process parameters involving charge transfer resistance (R c t ), double layer capacitance (C d l ), constant phase elements (CPE) and Warburg impedance in platinum substrate/platinum-modified polyaniline film/solution interface are discussed on the basis of the interpretation of the characteristic impedance spectra and connected to the electrocatalytic activity on the oxidation of methanol molecules.

The electrocatalytic properties of platinum particles incorporated into polyaniline films are investigated for oxidation of methanol in sulfuric acid electrolyte. It is found that the oxidation of methanol depends greatly on the nature of both polyaniline matrix and platinum particles which can be optimized by the electrochemical formation conditions, such as cycle numbers, sweep rates and potential limits.

The electrochemical impedance spectroscopy of a platinum-modified polyaniline film formed by cycling potential or constant potential deposition of platinum particles in polyaniline film is studied in sulfuric acid solution. The results show that compared with the pure polyaniline film ∣ H 2 SO 4 solution interface, the deposition of platinum in the polyaniline matrix greatly reduces the electrochemical charge transfer resistance ( R ct ) in the platinum-modified polyaniline film ∣ H 2 SO 4 solution interface. The surface morphology of the electrodes is observed by scanning electron microscopy. This shows that the different polarization modes affect the nature of the platinum deposits, such as their size, amount, real surface area and distribution in the polymer matrix. The electrocatalytic activity of platinum-modified polyaniline film electrodes for methanol oxidation is discussed on the basis of platinum loading and real surface area which result from varying electrodeposition modes, such as potential limits in cyclic potential polarization or selected potentials in constant potential polarization. Finally, the relationship between impedance characteristic and electrocatalytic activity has been suggested.

Change detection monitoring is an important method of remote sensing classification. This paper proposes Temporal-spatial-probabilistic model (TSPM) to improve the accuracy of classification, which the accuracy was reduced by the existing method, when the remote sensing image was contaminated by cloud. The study area is three countries in LiaoNing province using five Landsat 8 images. The result of TSPM classification is that the user's accuracy is 92.42%, the producer's accuracy is 85.62% and the overall accuracy is 86.91%. Thus we conclude that our proposed model (TSPM) is an efficient approach for remote sensing classification.

To explore the advantage, feasibility and safety of modified approach to difficult vaginal hysterectomy and provide scientific rationales for expanding its indications.A retrospective study was conducted for 237 patients undergoing hysterectomy for benign disease of uterus (without prolapse) from January 2009 to July 2012. Both modified approach to difficult vaginal hysterectomy (TVH, n = 167) and abdominal hysterectomy (TAH, n = 70) were performed. Two groups were compared for epidemiological, clinical characteristics, operative duration, intraoperative blood loss volume, perioperative and postoperative complications, hospitalization duration, inflammatory response and follow-up outcomes. TVH was divided into 3 subgroups of enlarged uterus (n = 100), prior pelvic surgeries/endometriosis history (n = 25) and complicated cases with multiple factors (n = 42). Then the surgical outcome parameters were compared for each group.The operative duration, intraoperative blood loss volume and blood transfusion amount were significantly less in the TVH group than those in the TAH group (P0.05). No major perioperative complications occurred in either group. There was no conversion from TVH into TAH. Inflammatory response, gastrointestinal recovery and hospitalization duration for the TVH group were significantly shorter than those of the TAH group (P0.05). The hospitalization expense was almost the same in two groups (P0.05). Postoperative complications and the quality of sexual health were not statistically different between two groups at 1 month and 6 months post-operation (P0.05). The data of three TVH subgroups were collected. The complicated cases with multiple factors group had longer hospitalization duration than the enlarged uterus and the prior pelvic surgeries/endometriosis history groups (P0.05). Similarly the volume of blood loss in the complicated cases with multiple factors group was significantly more than those of other two groups (P0.05).As one kind of mini-invasive surgery with less complications, higher safety and feasibility, modified approach to difficult vaginal hysterectomy offers shorter operative duration, less volume of blood loss and faster recovery.

Oncomelania hupensis (Gredler, 1881) is an intermediate host of Schistosomiasis japonica in China. In order to understand the factors controlling sedimentation and drifting of adult snails and snail eggs in rivers, three aspects were investigated by experiment. Firstly, the specific gravity of the snail eggs was found to be 2.29 g/cm3; secondly, the range of dropping speed of the snail eggs through a water column was found to be 1.19 to 3.77 cm/s; thirdly, a formula for dropping speed of the eggs was established. The formula was statistically validated by comparison with observed values. The results are relevant to both the development and design of irrigation scheme, and also to river management, where dispersal of snails and their eggs needs to be controlled.

To explore a new technique to prevent the dispersal of Oncomelania hupensis snail through leading flood for irrigation by floodgate in irrigation schemes.Hydromechanical and biological were applied and to combine laboratory experiment with the field observation to form a new multidisciplinary regarding snail biological hydraulics and technical line. Findings including characteristics of hydraulics and biomechanics and move regulation etc. Physics parameter of snails were used to design and construct as well as to exam the effect of facilities and rebuilt floodgate which could prevent the snail dispersal.Through five years efforts, the major achievements were found as: 1) the method in testing the special gravity of snail and snail eggs was determined. 2) the special gravity of snail was (1.8 +/- 0.01) g/cm(3) and special gravity snail eggs was (2.29 +/- 0.01) g/cm(3); the classification method and classified criterion of snail size were made based on geometrical characteristics of snail shell. Six special values indicating dropping and start speed of snail in running water were obtained; Five practical formula of snail dropping and start in water were established; threshold value and movement characteristics in water were observed and tested and move mechanism of snail dispersal in water was also clarified. Based on the findings from fundamental research, the facilities of "precipitation pool for snail" and "leading water from middle level of water body" that could prevent snail dispersal were designed and rebuilt in the endemic area. Through examination to these facilities, the rate of precipitating and blocking of snails reached 100%.The achievement of the study provided reliable theoretical basis for the rebuilt of floodgate and to development of models that could prevent the dispersal of snail effectively.