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Oedaleus decorus asiaticus (Bey-Bienko) is a destructive pest in grasslands and adjacent farmland in northern China, Mongolia, and other countries in Asia. It has been supposed that this insect pest can migrate a long distance and then induce huge damages, however, the migration mechanism is still unrevealed. The current study uses insect light trap data from Yanqing (Beijing), together with regional meteorological data to determine how air flow contributes to the long-distance migration of O. decorus asiaticus. Our results indicate that sinking airflow is the main factor leading to the insects' forced landing, and the prevailing northwest wind was associated with O. decorus asiaticus taking off in the northwest and moving southward with the airflow from July to September. Meanwhile, the insects have a strong migratory ability, flying along the airflow for several nights. Thus, when the airflow from the northwest met the northward-moving warm current from the southwest, a large number of insects were dropped due to sinking airflow, resulting in a large outbreak. Our simulations suggest that the source of the grasshoppers involved in these outbreaks during early 2000s in northern China probably is in Mongolia, and all evidence indicates that there are two important immigrant routes for O. decorus asiaticus migration from Mongolia to Beijing. These findings improves our understanding of the factors guiding O. decorus asiaticus migration, providing valuable information to reduce outbreaks in China that have origins from outside the country.

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Landscape patterns have a substantial effect on non-point source (NPS) pollution in watersheds. Facilitating sustainable development of mountain-rural areas is a major priority for China. Knowledge of the impacts of various landscapes on water quality in these areas is critical to meeting environmental goals. This study applied the Soil and Water Assessment Tool (SWAT) to create a hydrologic and water quality model of the study watershed; then, the relationship between water quality and landscape patterns was investigated using multiple linear regression and redundancy analysis. The results show that the western sub-basins had higher nitrogen pollution loads, and the total nitrogen concentration reached a maximum value of 3.91 mg/L; the eastern sub-basins had a higher pollution load of phosphorous featured by maximum total phosphorous concentration of 2.15 mg/L. The water quality of the entire watershed in all scenarios tended to deteriorate over time. Landscape metrics accounted for 81.7% of the total variation in pollutant indicators. The percentage of forest landscape was negatively correlated with NPS pollution, while other types of landscape showed a positive correlation. The patch density, landscape shape index, and largest patch index of urban and agricultural lands were negatively correlated with pollutant concentrations. Upland landscapes contributed more pollutants than paddy fields. Some measures, e.g., returning grassland and farmland to forest in steep regions and replacing upland crops with paddy fields, were recommended for mitigating NPS pollution in the study watershed.

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Study the suitability of organic film for salvianolic acid in the ultrafiltration process of Danshen Dizhuye. UPLC was used to analyze the migration of nine phenolic active ingredients in Danshen Dizhuye during ultrafiltration of PES hollow fiber membrane and PS hollow fiber membrane. The structural composition of multi-components was analyzed by three different batches of Danshen Dizhuye before and after ultrafiltration of the two membranes. The results showed that 9 phenolic active ingredients in Danshen Dizhuye did not change significantly after ultrafiltration through PES membrane. However, after ultrafiltration through PS membrane, the content of sodium danshensu, protocatechualdehyde, caffeic acid, 3-hydroxy-4-methoxycinnamic acid and rosmarinic acid in Danshen Dizhuye did not change significantly, while salvianolic acid D, salvianolic acid B and lithospermic acid decreased by about 20%, and the content of salvianolic acid A decreased significantly. The final content in equilibrium was only about 20% of the original solution. Therefore, an in-depth study on the migration particularity of salvianolic acid A in ultrafiltration membrane was the focuse. The results showed that the loss of salvianolic acid A was caused by both membranes during ultrafiltration, and salvianolic acid A was lost more in PS membrane. When the membrane was washed and regenerated, it was found that salvianolic acid A was detected in the ethanol washing solution, but not in the washing liquid, indicating that the loss of salvianolic acid A during the ultrafiltration was mainly adsorptive action. The results suggested that the migration of phenolic active ingredients in Danshen Dizhuye during the membrane ultrafiltration process did not completely follow the molecular weight passing rule of the membrane pore size. At the same time, it may be affected by factors, such as the structure of the membrane material, and the interaction between the membrane structure and the structure of components, and exhibit different migration behaviors during the ultrafiltration of the membrane.

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RESUMEN

Study the suitability of organic film for salvianolic acid in the ultrafiltration process of Danshen Dizhuye. UPLC was used to analyze the migration of nine phenolic active ingredients in Danshen Dizhuye during ultrafiltration of PES hollow fiber membrane and PS hollow fiber membrane. The structural composition of multi-components was analyzed by three different batches of Danshen Dizhuye before and after ultrafiltration of the two membranes. The results showed that 9 phenolic active ingredients in Danshen Dizhuye did not change significantly after ultrafiltration through PES membrane. However, after ultrafiltration through PS membrane, the content of sodium danshensu, protocatechualdehyde, caffeic acid, 3-hydroxy-4-methoxycinnamic acid and rosmarinic acid in Danshen Dizhuye did not change significantly, while salvianolic acid D, salvianolic acid B and lithospermic acid decreased by about 20%, and the content of salvianolic acid A decreased significantly. The final content in equilibrium was only about 20% of the original solution. Therefore, an in-depth study on the migration particularity of salvianolic acid A in ultrafiltration membrane was the focuse. The results showed that the loss of salvianolic acid A was caused by both membranes during ultrafiltration, and salvianolic acid A was lost more in PS membrane. When the membrane was washed and regenerated, it was found that salvianolic acid A was detected in the ethanol washing solution, but not in the washing liquid, indicating that the loss of salvianolic acid A during the ultrafiltration was mainly adsorptive action. The results suggested that the migration of phenolic active ingredients in Danshen Dizhuye during the membrane ultrafiltration process did not completely follow the molecular weight passing rule of the membrane pore size. At the same time, it may be affected by factors, such as the structure of the membrane material, and the interaction between the membrane structure and the structure of components, and exhibit different migration behaviors during the ultrafiltration of the membrane.

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Wood preservatives in wooden children's products (WCPs) may migrate into children's body through oral and dermal exposure, resulting in a potential health risk. In this paper, a systematic investigation on the migration regularity of lindane and five chlorophenols preservatives from WCPs to saliva and sweat was introduced. Migration models were established based on the abundant migration data among different time periods (2 min-96 h). Wood exhibited complex porosity for various species, resulting in the deviation of the migration of preservatives from different samples. By introducing a correction coefficient (f) calculated based on the sample microstructure (specific surface area and pore distribution), the predicted values of correcting migration model matched better with the experimental data. Migration data indicated that exposure risks should be noticed when children were in contact with WCPs because a considerable quantity of preservatives migrated into the body in a short time. This work is expected to play a role in the formulation of chemical limit standards to promote the safety of WCPs, and may serve ideas as basis for the migration research of chemicals in wooden products.

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