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Net cage aquaculture has a significant impact on the regional water environment, and studying the changes in water quality parameters in net cage aquaculture areas is of great practical significance for understanding the impact of regional aquaculture on the water environment. This article uses GF-1WFV data to construct an inversion model for the total suspended solids concentration in the net cage aquaculture area, which has grown exponentially in the Manwan Reservoir area in recent years. The results indicate that the model has high accuracy, with an average relative error of 9.65% between the inverted values and the measured values, and a root mean square error of 0.33mg/L. Based on the constructed inversion model and satellite imagery, the total suspended solids concentration in the Manwan net cage aquaculture area was inverted, and the variation patterns of total suspended solids concentration in the reservoir area and different net box positions were analyzed. Research has found that the variation pattern of suspended solids concentration in the Manwan reservoir area and different positions of net cages is basically consistent. The total suspended solids concentration in net cages has not shown any abnormalities due to the phenomenon of local "delineation" in aquaculture, but is lower than the overall suspended solids concentration in the reservoir area. This is mainly because the variation of total suspended solids concentration is mainly affected by precipitation, surface runoff, water flow velocity, etc. Net cage aquaculture can reduce its impact on the total suspended solids concentration in local "delineation" areas. This study has certain reference significance for understanding the changes in total suspended solids concentration in the Manwan reservoir area and net cage aquaculture area. In the future, a multi-source remote sensing data remote sensing estimation model for water quality parameters will be developed for understanding the changing patterns in water environment in the Manwan net cage aquaculture area. [ABSTRACT FROM AUTHOR]

Coumarins are a group of natural compounds commonly found in the families of Rutaceae and Umbelliferae. 7‐Isopentenyloxycoumarin (ISC), auraptene (AUR), and umbelliprenin (UM) belong to prenyloxycoumarins (PYCs), which link isopentenyl, geranyl, and farnesyl group at C7 position, respectively. The substituent of 7‐ethoxycoumarin (ETC) is the ethyl group. In this study, UPLC–ESI–QTOF–MS (ultra‐performance liquid chromatography–electrospray ionization–quadrupole time of flight–MS)‐based metabolomics was used to evaluate the in vivo and in vitro metabolism of PYCs. Results showed that ETC produced 10 known metabolites, and ISC was transformed into 17 metabolites in vivo and in vitro, which were undescribed compounds. A total of 35 AUR metabolites, including 34 undescribed metabolites were identified, and 21 metabolites were reported for the first time in UM. The results indicated that hydroxylation and N‐acetylcysteine conjugation were the common metabolic reactions for PYCs. The metabolic rates of ETC, ISC, AUR and UM were 26%, 36%, 81%, and 38%, respectively, in human liver microsome, while they were 24%, 40%, 80%, and 37%, respectively, in mouse liver microsomes. In addition, recombinant cytochrome P450s (CYPs) screening showed that CYP1A1, 2C19, 3A4, and 3A5 were the major metabolic enzymes involved in the formation of hydroxylation metabolites. Together, these results suggest that the isopentenyl group plays an important role in the metabolism of PYCs. [ABSTRACT FROM AUTHOR]

Objective To analyze the changes of lipid profiles and atherogenic index of plasma (AIP) in Human Immunodeficiency Virus (HIV)/Acquired-Immune Deficiency Syndrome (AIDS) patients after 48 and 96 weeks of antiretroviral therapy (ART), to evaluate the risk factors of cardiovascular disease in HIV / AIDS patients after art treatment. Methods Total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were assessed, and Non-HDL-C (NHC), Castelli's risk index I and II (CRI-I, CRI-II), insulin resistance surrogate (IRS), AIP were calculated in HIV/AIDS patients. Results The incidence of abnormal TC, TG, HDL-C, LDL-C, NHC and AIP increased, and the difference of TC,TG,LDL-C and NHC was statistically significant (P<0.05); the incidence of HDL-C, CRI- I and CRI- H abnormalities decreased, and there was significant difference in HDL-C (P<0.05) in 384 patients after 48 and 96 weeks of ART. At baseline, 48 weeks and 96 weeks after art, AIP was significantly different in different age groups (P< 0.05), and there was a significant positive correlation with age (r=0.208, 0.183, 0.170, P<0.001). There was significant difference in AIP between normal TG group and abnormal TG group (P<0.05), and there was a significant positive correlation with baseline TG (r=0.841, 0.641, 0.602, P<0.001). AIP had significant difference between normal HDL-C group and abnormal HDL-C group (P<0.05), and had a significant negative correlation with baseline HDL-C (r=-0.608, -0.390, -0.326, P<0.001). It was not related with CD4 counts, HIV-RNA virus load, baseline TC and LDC-C. Logistic regression analysis was carried out determine the risk factors of abnormal AIP value. The results shows that compared with 18-<30 years old, HIV/AIDS patients over 30 years old were the risk factors of abnormal AIP after 48 and 96 weeks of ART (OR=2.02, 95% CI: 1.30-3.13, P<0.01; OR=1.77, 95%CI: 1.13-2.78, P<0.05). Conclusions Dyslipidemia is present in HIV/AIDS patients after ART. Age is a risk factor for plasma atherosclerosis in HIV/AIDS patients. Lipid levels need to be monitored regularly after ART, especially to HIV/ AIDS patients with ≥ 30 years, to reduce the risk of cardiovascular disease. [ABSTRACT FROM AUTHOR]

A visible‐light‐driven and room temperature photo‐Wolff‐Kischner reaction of sulfur ylides and N‐tosylhydrazones has been developed for the first time to provide modular access to alkene synthesis. The high functional group tolerance and broad substrate scope were demonstrated by more than 60 examples. Both E‐ and Z‐olefinic stereochemistry in the products could be controlled with excellent stereoselectivity. A series of mechanistic studies support that the reaction should proceed through a radical‐carbanion crossover pathway, specifically involving addition of photo‐generated sulfur ylide radical cations to N‐tosylhydrazones to form carbanions and subsequent Wolff‐Kischner process. [ABSTRACT FROM AUTHOR]

The 2,3‐dihydrobenzofuran ring systems are a privileged class of oxygen heterocycles, and their synthesis continues to attract considerable effort. Herein, a visible‐light‐driven photoredox‐catalyzed radical multicomponent cyclization of 2‐vinyl phenols, N‐alkoxypyridinium salts, and sulfur ylides is described. The key to the reaction success involves the use of both N‐alkoxypyridinium salts and sulfur ylides as radical precursors. This redox‐neutral protocol features good functional group tolerance, easily available starting materials, simple operation, and mild reaction conditions, enabling the modular synthesis of various 2,3‐disubstituted dihydrobenzofurans. Mechanistic studies have also elucidated some of the aspects associated with the key radical intermediates. [ABSTRACT FROM AUTHOR]