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A dynamic kinetic model is presented for the UVC/H2O2-driven process. The model comprises 103 reactions, including background species, such as HCO3-/CO32-, NO2-, NO3-, SO42-, Cl-, and H2PO4-/HPO42/PO43- anions, and effluent organic matter (EfOM) was validated based on experimental data obtained for the photooxidation of the nonribosomal peptide antibiotic zinc bacitracin (Zn-Bc, 34 μmol L-1). The set of ordinary differential equations for 38 species was combined with the molar balances describing the recirculating tubular photoreactor used. Predictions for the photolytic and UVC/H2O2 processes confirmed the good agreement with experimental data, enabling the estimation of fundamental kinetic parameters, such as the direct photolysis quantum yield (Ф254 nm, Zn-Bc = 0.0143 mol Einstein-1) and the second-order rate constants for the reactions of Zn-Bc with HO•, HO2•, and O2•- radicals (2.64 × 109, 1.63 × 103, and 1.49 × 104 L mol-1 s-1, respectively). The predicted optimum process conditions correspond to [H2O2]0 = 6.8 mmol L-1 and a specific photon emission rate of 11.1 × 10-6 Einstein L-1 s-1. Zn-Bc photooxidation was significantly impacted by wastewater constituents, particularly EfOM and HCO3-/CO32- (i.e., alkalinity), resulting in a degradation rate about 32% lower compared to that obtained in deionized water. In particular, EfOM acts as a strong radical scavenger and inner filter. In addition, simulations pointed out the continuous tubular photochemical reactor as the best configuration for treating Zn-Bc-containing wastewater. This study hence provides a comprehensive modeling approach, especially useful for predicting the effect of complex water matrices on the performance of the UVC/H2O2 treatment process.Faced with huge environmental problems of ecosystem degradation, “Ecological Redline Policy (ERP)” in China is a new key national-level policy to manage different land use functions in accordance with development and environmental limits. As the water-land complex ecosystem with the largest freshwater lake, wetland natural reserves and ecological importance in China, Poyang Lake Region (PLR) is selected to quantify and map multiple ecosystem services, investigate the ecological function zoning as part of research on ecological zoning control and major ecological source areas to illustrate and address the implementation of this strategy based on the importance and vulnerability analysis of ecosystem services. According to ecological function zoning results, extremely important, highly important, medium important and important zones respectively account for 26.1%, 28.1%, 17.4% and 28.4% of the total area. With an area of 5422.2 km2, the extremely important zone is 1010.6 km2 larger than the ERP. Moreover, 81.6% of the ERP is located in the extremely important zone. learn more By discussing the implications and applications of ecological management, this study contributes to the ecological protection of Poyang Lake and provides a foundation for research on ecological function zoning at the regional scale.To analyze the cumulative risks to the water environment, the backpropagation artificial neural network (BP-ANN), a self-adapting algorithm, was proposed in this study. A new comprehensive indicator of cumulative risks was formed by combining the water risk assessment tool proposed by the World Wide Fund for Nature or World Wildlife Fund (WWF), Deutsche Investitions und Entwicklungsgesellschaft mbH (DEG), and the cumulative environmental risk assessment system proposed by the US Environmental Protection Agency (USEPA). Eleven training algorithms were selected and optimized based on the mean square error (MSE) of prediction results. Data concerning evaluating indicators and cumulative risk indexes of the Liao River collected from 2005 to 2017 in the cities of Tieling, Shenyang, and Panjin, China, were used as input and output data to train, validate, and test the BP-ANN. Levenberg Marquardt backpropagation was the most accurate algorithm, with an MSE of 3.33 × 10-6. After optimization, there were six hidden layers in the model. The correlation coefficient of the BP-ANN with LM exceeded 80%. These findings suggest that the BP-ANN model is applicable to prediction of cumulative risks to the water environment. The model was sensitive to the number of wastewater treatment facilities and the wastewater treatment rate along the river. Based on the sensitivity analysis, the contributing factors can be controlled to reduce the cumulative risk.Acrylamide (AA) is a hazardous chemical that is widely used in industrial practices. Spirulina platensis (SP) is a blue green alga that is rich in bioactive compounds with many medicinal benefits. The aim of the present study was to evaluate the ameliorative effect of SP against AA toxicity in rats. Animals were divided into six groups Group (1) was normal rats, groups (2) and (3) received SP at 500 and 1000 mg/kg BW orally respectively for 21 days, group (4) was administered 20 mg/kg BW AA daily for 14 days, while groups (5) and (6) were given orally SP at the same doses of groups (2) and (3), then AA at similar dose of group (4). Rats that received AA alone displayed markedly increased serum levels of liver enzymes (ALT, AST, and ALP), kidney function parameters (urea and creatinine), DNA damage marker (8-OHdG), and proinflammatory cytokines (IL-1β, IL-6, and TNF-α), compared to control rats. Furthermore, tissue analysis revealed marked increases in hepatic, renal, and brain MDA and NO, as well as marked reductions in the antioxidant biomarkers (GSH, GSH-Px, SOD, and CAT) in acrylamide-intoxicated rats. Spirulina ameliorated the alterations in serum biochemical parameters and reduced MDA and NO, as well as improved antioxidant biomarkers in AA-intoxicated rats in a dose-dependent manner. Our results show that SP has a powerful protective effect on serum biochemistry and liver, kidney, and brain antioxidant machinery in AA-intoxicated rats.

Arterial stiffness is a risk factor for chronic kidney disease progression (CKD). Pulse pressure is a surrogate marker of arterial stiffness. It is unclear if pulse pressure predicts CKD progression in type 2 diabetes mellitus.

This was prospective study involving 1494 patients with estimated glomerular filtration rate (eGFR) ≥ 15ml/min/1.73 m

. Carotid-femoral pulse wave velocity was measured using applanation tonometry. Pulse pressure was calculated as difference between systolic and diastolic blood pressures. CKD progression was defined as worsening of eGFR categories (stage 1, ≥ 90ml/min/1.73m

; stage 2, 60-89ml/min/1.73m

; stage 3a, 45-59ml/min/1.73m

; stage 3b, 30-44ml/min/1.73m

; stage 4; 15-29ml/min/1.73m

; and stage 5, < 15ml/min/1.73m

) with ≥ 25% decrease in eGFR from baseline.

After follow-up of up to 6years, CKD progression occurred in 33.5% of subjects. Subjects in 2nd, 3rd and 4th quartiles of peripheral pulse pressure experienced higher risk of CKD progression with unadjusted hazard ratios (HRs) 1.