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The influence of environmental quality on the quality of urban life and on migration decisions is an important research issue in urban economics and environmental economics. Using the 2012–2014 China Labor Dynamics Survey data (CLDS), this paper uses a conditional logit model (CLM) and Instrumental Variable (IV) estimation to examine the impact of air pollution on the migrant migration decision. We find that air pollution significantly negatively impacts the migration decisions of migrants. Specifically, if the PM2.5 level of a city increases by 10 μg/m3, the probability of migrants flowing into the city will be significantly reduced by 21.2%. It shows that migrants choose to flow into cities with better spatial quality to reduce the risk of exposure to air pollution. After controlling for the characteristics of the outflow and the reasons for the flow, the impact of air pollution on migrants’ migration decisions remains robust. Heterogeneity analysis shows that middle-aged, male, married, and highly educated migrants are more sensitive to air pollution. This paper enriches the research on air pollution and labor mobility at the micro level and provides empirical evidence for policymaking related to environmental governance and labor mobility in a low-carbon society.

Peanut stem rot caused by Sclerotium rolfsii Sacc. is the most common disease of peanut worldwide and has become increasingly serious in recent years. This study is aimed at obtaining peanut endophytic bacteria with high antagonistic/protective effects against peanut stem rot. In total, 45 bacterial strains were isolated from healthy peanut plants from a severely impacted area. Of these, 6 exhibited antagonistic activity against S. rolfsii, including F-1 and R-11 with the most robust activity with an inhibition zone width of 20.25 and 15.49 mm, respectively. These two were identified as Bacillus sp. and Burkholderia sp., respectively, based on morphological, physiological, and biochemical characteristics and 16S rDNA sequencing. To the best of our knowledge, this is the first study to report the Burkholderia sp. antagonistic effect on S. rolfsii as a biological control agent for peanut stem rot. Their culture filtrates potently inhibited the hyphal growth, sclerotial formation, and germination of S. rolfsii. Also, the strain-produced volatile compounds inhibited the fungal growth. Pot experiments showed that F-1 and R-11 significantly reduced the peanut stem rot disease with the efficacy of 77.13 and 64.78%, respectively, which was significantly higher compared with carbendazim medicament (35.22%; P Bacillus sp. F-1 and Burkholderia sp. R-11, with a strong antagonistic effect on S. rolfsii, can be potential biocontrol agents for peanut stem rot.

The discharge of wastewater containing hexavalent chromium (Cr(VI)) into the environment is very harmful to living things. Therefore, before effluent that contains Cr(VI) can be discharged into the environment, this toxin should be removed from the contaminated water. In this study, corn stalk biochar was investigated to evaluate the Cr(VI) removal efficiency from an aqueous solution. The effects of pH (2–10), biochar concentration (0.5 to 10 g/L), Cr(VI) concentration (10–500 mg/L), and contact time (10–1440 min) were studied. The actual experimental value of the Cr(VI) removal efficiency was 28.67%, largely consistent with the predicted model value of 29.31%, under the optimal conditions of a Cr(VI) concentration of 60 g/L, pH 4, contact time of 270 min, and a biochar concentration of 4.5 g/L. A significant interaction between the Cr(VI) concentration and pH was observed, along with significance in the interaction between Cr(VI) concentration and biochar concentration, which had a greater impact on the removal of Cr(VI). Biosorption onto corn stalk biochar is an affordable and economical adsorption process to treat wastewater contaminated with Cr(VI). The aim of this study is to provide data to serve as a basis for future studies on the use of raw agricultural waste to remove Cr(VI).

Background Influenced by various factors, endoscopists have shown differences in the detection rate of adenomas (ADR) during different periods of endoscopy every day. The purpose of this study is to observe whether AI-assisted endoscopy can bring an improvement in ADR and whether the increase is consistent in different periods. Methods We established a real-time AI-assisted colonoscopy system. The core of the system is a deep neural network for object detection, YOLOV3. The processing speed of this model was 60FPS. When polyps appear in the video of colonoscopy, the system can give a real-time warning on the monitor of the endoscope. We randomly divided the enrolled patients into four groups, which were arranged to receive colonoscopy in the first hour of the morning and the last hour of the morning, respectively. Meanwhile, we differentiated the AI-assisted group and the non-AI-assisted group. In order to remove the bias caused by the experience of the endoscopist, the trial was performed by two colonoscopists with comparable experience. Finally, the ADRs among the groups were compared. Results With or without AI, endoscopy scheduled in the first hour of the morning had higher ADRs than endoscopy scheduled in the last hour of the morning (23% Vs 18%). AI assistance had a positive effect on the increase in ADR, but it had a greater effect on endoscopy scheduled in the latter period. (0.5% Vs 4.2%). Conclusions The change of ADR detection rate in different time periods was mainly due to the change of attention of endoscopists, which had little correlation with the level of endoscopic operation. The use of artificial intelligence assistance can help endoscopic doctors improve their attention and ensure the stability of the ADR in different periods.

As a widely used herbicide, picloram has been frequently detected in the aquatic environment due to its high leaching potential and low adsorption by soil. To reduce aquatic environmental risk of this herbicide caused by leaching and runoff, five herbicidal ionic liquids (HILs) based on picloram were prepared by pairing isopropylamine, octylamine, octadecylamine, 1-methylimidazole, 4-methylmorpholine respectively. Their physicochemical properties including water solubility, octanol-water partition coefficient, surface activity, leaching, as well as soil adsorption were compared. The results showed that these properties could be adjusted by appropriate selection of counter cations. The HILs with long alkyl chains in cations had low water solubility and leaching characteristics, good surface tension and lipophilicity, as well as high soil adsorption. Compared with currently used picloram in the forms of potassium salts, HIL3 had more excellent herbicidal activity against broadleaf weeds and may offer a lower use dosage. The HILs based on picloram can reduce its negative effects on the aquatic environment and can be used as a desirable alternative to commercial herbicidal formulations of picloram in future.

Emodin has demonstrated potent anticancer activity in human hepatocarcinoma cells and animal models, however, the cellular targets of emodin have not been fully defined. Here we report that emodin induces the dysfunction of mitochondria and the apoptosis in HepG2 cells through an enrichment in mitochondria. Specifically, A mitochondrial matrix protein (cyclophilin D, CyPD) is involved in emodin-induced apoptosis, and the inhibitor of CyPD (cyclosporin A) could almost completely suppressing the apoptosis; Moreover, as the expression of CyPD could be effectively inhibited by antioxidant N-acetyl-l-cysteine and epidermal growth factor (the activator of ERK), reactive oxygen species and ERK might be involved in the relevant role of CyPD. A further molecule-docking discloses the existence of three hydrogen-bonds in CyPD-emodin complex. Thus, target localization and CyPD in mitochondria provides an insight into the action of emodin in the treatment of liver cancer.

The excessive application of water-soluble pesticides poses enormous potential risks to groundwater by leaching or in runoff. Ionic liquids can regulate the physicochemical properties of pesticides and surmount their disadvantages. In this study, five herbicidal ionic liquids (HILs) based on clopyralid have been synthesized and characterized to reduce the risks to the aquatic environment and improve the herbicidal activity. The new HILs are prepared by pairing isopropylamine, 1-dodecylamine, 2-benzothiazolamine, 1-methylimidazole, benzyltriethylammonium chloride respectively. The results of the solubility, soil adsorption, surface activity, leaching characteristic and herbicidal activity of HILs show that the physicochemical properties can be optimized by selecting different counter cations. Compared with clopyralid potassium, HILs have better herbicidal activity, greater adsorption capacity and lower leaching characteristic. The HILs of clopyralid can reduce its hazardous impacts on the aquatic environment, suggesting a desirable candidate in clopyralid application in the future.

Controlled release formulations of pesticides is highly desirable for maximising the utilization of the pesticide, as well as remarkably reducing environmental pollution. A stimuli-responsive controlled release formulation can intelligently respond to the stimuli produced by pests and trigger the release of the active ingredients to control pests effectively. In this work, a novel enzyme-responsive emamectin benzoate microcapsule was prepared using silica cross-linked with carboxymethylcellulose using epichlorohydrin. The results showed that the obtained microcapsules had a remarkable loading ability for emamectin benzoate (about 35% w/w) and could protect emamectin benzoate against photo- and thermal degradation effectively. The silica–epichlorohydrin–carboxymethylcellulose microcapsules displayed excellent cellulase stimuli-responsive properties and a sustained insecticidal efficacy against Myzus persicae. Allium cepa chromosome aberration assays demonstrated that the microcapsules had less genotoxicity than the technical grade emamectin benzoate (referred to throughout the manuscript as the technical). Given these advantages, the enzyme-responsive emamectin benzoate microcapsules are worth extending as a novel safe strategy for sustainable crop protection.

The 1,4-naphthoquinone derivatives bearing 5,7-dimethoxyl moiety were designed, synthesized, and tested as the antitumor agents against five human cancer cell lines (A549, Hela, HepG2, NCI-H460 and HL-60). All the compounds are described herein for the first time. The structure-activity relationships indicated that the presence of chlorine atom at the 2-position was crucial for the antiproliferative activity. Further, the electrochemical properties of the representative compounds (7e, 8e and 9e) were evaluated and a definite correlation between the redox potential and the antiproliferative activity. The most potent compound 9e displayed significant anti-leukemic activity with IC50 value of 3.8 μM in HL-60 cells and weak cytotoxicity with IC50 of 40.7 μM in normal cells WI-38. In mechanistic study for 9e, the increased numbers of apoptotic cells and increased cell population at G2/M phase correlated with ROS generation. Together, our results suggested that the derivatives of 2-chlorine-1,4-naphthoquinone might be the promising candidates for the treatment of promyelocytic leukemia.

The excessive application of pesticides increases the pollution potential, which leads to groundwater contamination and spreading of toxic substances in the environment by leaching or in runoff. In this study, new herbicide ionic liquids (HILs) based on fomesafen with multifunctions were prepared to improve the herbicidal activity and reduce the risk to the aquatic organisms. The octanol–water partition coefficient (Kow), surface activity, soil adsorption and herbicidal activity of HILs were tested and a comparative analysis with fomesafen was made. The results show that HILs have low water solubility, excellent Kow, low surface tension, and good adsorption ability, and these properties can be regulated and optimized by selecting different counter cations. The physico-chemical properties of HILs were related to the carbon chain length of the cation. Compared with fomesafen sodium, ionic liquids N-1 showed a higher and faster herbicidal activity because of its good lipophilicity and low surface tension. HILs with lower water solubility and greater adsorption capacity in soil have less risk to algae, snail and other aquatic organisms than fomesafen sodium. The HILs will be a candidate in fomesafen applications in the future.

The controlled and targeted release of pesticides with high water solubility has been a challenge for integrated pest management. In this paper, kasugamycin, an antibiotic broadly used in plant disease control, was covalently conjugated to pectin to form a kasugamycin-pectin conjugate by an amide bond. The conjugate was structurally characterized by Fourier transform infrared spectroscopy, ultraviolet spectrophotometry, and thermal gravimetric analysis. The results showed that the conjugate was stable over a wide range of pH and temperatures, as well as under UV irradiation. When incubated with Pseudomonas syringae pv. lachrymans, the conjugate could be activated, releasing the kasugamycin, which made it a promising controlled-release formulation of pesticide.

Ractopamine (RAC) has been approved as a feed additive for swine, cattle or turkey, and is likely to have residue in edible animal products and may pose a potential risk for consumer health. Therefore, it is essential to establish a method to detect the residue of RAC in animal products. This work presents a rapid and sensitive HPLC method for the determination of RAC in pork samples with pre-column derivatization. The RAC derivative was separated on a kromasil C18 column and detected at 284 nm with a UV detector. The detection capability (CCβ) was 0.078 μg g − 1 and the linearity was established over the concentration range of 0.15–100.0 μg g − 1 . The overall mean recovery in spike range of 0.2 μg g − 1 to 100 μg g − 1 was 89.9% with the overall mean relative standard deviation of 4.1%. This method can be used for the quantification of RAC in pork samples and help to establish adequate monitoring of the residue of RAC.

New auxinic herbicide derivatives with high-activity and low-volatility are required urgently to solve the growing problems of weed resistance and volatile drifting which severely limit the application of auxinic herbicides (2,4-D, MCPA and dicamba). In this study, a series of auxinic herbicide derivatives were prepared using 2,4-D, MCPA and dicamba as lead compounds by me-too method. The volatility, greenhouse herbicidal activity against four common weeds and field herbicidal activity were evaluated and a comparative analysis with the corresponding lead compound was made. Results of volatility test indicated that it was possible to get a low-volatile compound even when the reactants were both highly volatile and the compounds with intermolecular hydrogen bond showed the comparatively low volatility. In the greenhouse herbicidal activity test, the compounds with ester bond had faster and higher herbicidal activities and better inhibition phenotypes than the compounds with amide bond. The compounds (R)-ethyl 2-(4-(2-(2,4-dichlorophenoxy)acetoxy)phenoxy)propanoate (3a-9), (R)-ethyl 2-(4-(2-(4-chloro-2-methylphenoxy)acetoxy)phenoxy)propanoate (3a-18) and (R)-4-((1-ethoxy-1-oxopropan-2-yl)oxy)phenyl 3,6-dichloro-2-methoxybenzoate (3b-7) showed lower volatilities and faster and higher activities in the greenhouse and field test than the corresponding lead compound and could be potential herbicides for further development. Keywords: Auxinic herbicide derivative, Herbicidal activity, Volatility, Me-too method