The utilization of allelochemicals to inhibit algal overgrowth is a promising approach for controlling harmful algal blooms (HABs). Quercetin has been found to have an allelopathic effect on algae. However, its responsive mechanism needs to be better understood. In the present study, the inhibitory effects of different quercetin concentrations on M. aeruginosa were evaluated, and the inhibition mechanisms were explored. The results demonstrated that quercetin significantly inhibited M. aeruginosa growth, and the inhibitory effect was concentration-dependent. The inhibition rate of 40 mg L−1 quercetin on algal density reached 90.79% after 96 h treatment. The concentration of chlorophyll-a (chl-a) in treatment groups with quercetin concentrations of 10, 20, and 40 mg L−1 decreased by 59.74%, 74.77%, and 80.66% at 96 h, respectively. Furthermore, quercetin affects photosynthesis and damages the cell membrane, respiratory system, and enzyme system. All photosynthetic fluorescence parameters, including the maximum photochemical quantum yield (Fv/Fm), the actual photochemical quantum yield (YII), the maximum relative electron transfer rate (rETRmax), and light use efficiency (α), exhibited a downtrend after exposure. After treatment with 20 mg L−1 quercetin, the nucleic acid and protein content in the algal solution increased, and the respiration rate of algae decreased significantly. Additionally, superoxide dismutase (SOD) activities significantly increased as a response to oxidative stress. In comparison, the activities of ribulose 1,5-biphosphate carboxylase (Rubisco) and phosphoenolpyruvate carboxylase (PEPC) decreased significantly. These results revealed that quercetin could inhibit M. aeruginosa by affecting its photosynthesis, respiration, cell membrane, and enzymic system. These results are promising for controlling M. aeruginosa effectively.

Giardia duodenalis is a common zoonotic intestinal parasitic protozoan and sheep are among its hosts; however, limited information is available on sheep kept in large-scale housing. The Hu sheep is a first-class protected local livestock breed in China. In this study, we investigated the seasonal dynamics of G. duodenalis infection in Hu sheep and the environmental contamination of large-scale sheep farms. We collected 474 fecal samples and 312 environmental samples from Hu sheep on a large-scale sheep farm in Henan, China. The prevalence of G. duodenalis was determined by nested PCR targeting the β‑giardin (bg) gene. The assemblages and multilocus genotypes (MLGs) were investigated based on analyses of three genetic loci, i.e. bg, glutamate dehydrogenase (gdh), and triosephosphate isomerase (tpi). To detect mixed infections of different assemblages, assemblage A/E-specific PCRs were performed to amplify the tpi gene. The prevalence of G. duodenalis infection in sheep was 17.9% (81/474) and the positivity rate in environmental samples was 0.96% (3/312). Genetic analysis revealed the presence of two assemblages (assemblages A and E), with assemblage E being detected in both fecal and environmental samples, and assemblage A detected only in fecal samples. A total of 23 MLGs were obtained in fecal and environmental samples, all of which belonged to assemblage E. These results indicate the seasonal dynamics of G. duodenalis infection in sheep and environmental contamination on large-scale housing sheep farms and provide an important reference for the prevention and control of G. duodenalis on large-scale housing sheep farms.

Anglo-American literature is an important part of world literature. It systematically reflects the development of the history, culture, religion, arts and natural sciences in Anglo-American countries. Therefore, it is of crucial importance to improve the effectiveness of Anglo-American literary teaching. The new curriculum reform calls for the reform of the old-fashioned and boring teaching methods of traditional Anglo-American literature to enhance the image, vividness and diversity of teaching. Therefore, the application of the original film in English and American literature class can strengthen students' cognition of literary works and deepen the comprehension of the works. Fully stimulate their interest in learning. The article mainly discusses the application of the original film in Anglo-American literature teaching. 1. The Application Advantages of the Original Movie in Anglo-American Literature After more than a hundred years' development, the film has been developing in a high-tech and diversified direction. Among them, the works adapted from the original works of classic literature are so numerous that the advantages of the original film as an adjunct to Anglo-American literature are beyond doubt: Students only show a strong interest in learning objects and enthusiasm can really stimulate their motivation to learn, get a better learning effect. Traditional Anglo-American literature is mostly taught by teachers. Students listen, the forms are dull, the contents are boring and cannot stimulate students' enthusiasm for learning. The original film is a collection of sound, light, video and other elements. Students cannot only enjoy the more interesting videos, but also master the knowledge in the process of watching the videos. By combining the contents of the videos with the textbooks, students are greatly encouraged to learn interest and urge students to read English and American literature related to movies and enhances the learning effect. Language acquisition requires a good language environment. Non-native English speakers lack the necessary language environment. However, the original film contains a great deal of dialogue or soliloquy, which becomes the best material to improve students' language ability. After a period of study, college students already have the ability to read, write and translate. By watching videos, they can review the application of what they have learned and improve their speaking ability and listening skills. Compared with the textbooks, the original film not only has vivid images, twists and turns of the story, more original language material, students master the knowledge in the process of watching the movie, improve the effectiveness of language learning. Literature comes from life. Many Anglo-American literary works have specific historical background and events. The more they understand these cultural backgrounds, the more favorable their students acquire knowledge and eliminate reading disabilities. The original film precisely creates a true culture for students Atmosph...

Rhipicephalus microplus is a major threat to the cattle industry worldwide. The intensive use of acaricides and repellents has resulted in drug resistance. Hence, effective and eco-friendly pest control alternatives are urgently needed, especially from natural plant resources. In this study, the acaricidal and repellent activities of nine herbs against the larvae and eggs of R. microplus were evaluated. The results showed that ethanol extracts of star anise (Illicium verum), chaulmoogra (Hydnocarpus anthelmintica), motherwart (Leonurus artemisia), mandarin orange peel (citri reticulatae pericarpium, i.e., peel of Citrus reticulata fruit), and stemona (Stemona sessilifolia) had good contact acaricidal activities of 100, 98, 94, 88 and 86%, respectively, whereas star anise and clove (Syzygium aromaticum) had good fumigant acaricidal activities of 98 and 96%, respectively. The hatching inhibition rate of star anise against R. microplus eggs was 100%. All nine herbs had good real-time repellent rates, but only castor bean and star anise had repellent effects after 48 h (81.3 and 79.6%, respectively). This is the first report of the acaricidal and repellent activities of these medicinal herbs against R. microplus. Ethanol extracts of these herbs might be considered as potential alternatives to chemical acaricides for control of R. microplus.