A rapid, simple, and sensitive method has been developed for the analysis of pyrethroid herbicides in fruits by using headspace in-tube microextraction (HS-ITME) coupled with reverse-flow micellar electrokinetic capillary chromatography (RF-MECC). In the newly developed method, by placing a capillary filled with background electrolyte (BGE) of RF-MECC in the HS above the sample solution, the pyrethroid herbicides were extracted into the acceptor phase in the capillary. After extraction, electrophoresis of the extracts in the capillary was carried out. The influence of some essential BGE components such as sodium dodecyl sulfate (SDS) and organic modifiers concentrations was investigated. Extraction parameters were also systematically investigated, including the extraction temperature, extraction time, salt concentration, and volume of the sample solution. Under the optimized conditions, enrichment factors for three pyrethroids were 309, 133, and 288, respectively. The proposed method provided a good linearity, low limits of detection (below 1.00 ng/mL), and good repeatability of the extractions (relative standard deviations [RSDs] below 7.83%, n = 6). The fruit samples were analyzed by the proposed method, and the obtained results indicated that the proposed method provides acceptable recoveries and precisions.
The traditional baseball instruction strategies were mainly conducted by the instructors with oral explanation and exemplification while students had to improve their performance in athletic activities through continuous practice. During the learning process of athletic skills, students oftentimes posed less confidence due to unskilled body movement resulting in lower achievement sense. Finally, they started to reject the engagement in relevant athletic activities and even never practice anymore. Therefore, this research aimed to explore the influence on the learning motivation and the performance of athletic skills made by students in the conventionally instructive mode by introducing the Computer-Aided Design (CAD) instruction strategies of the kinect baseball learning system. Research results indicated: (1) after the kinect baseball learning system was introduced into instruction, it positively affected the learning motivation of students; (2) after the kinect baseball learning system was introduced into instruction, it positively affected the performance of athletic skills of students.
The peptide trefoil factor family 3 (TFF3) is a major constituent of the intestinal mucus, playing an important role in the repair of epithelial surfaces. To further understand the role of TFF3 in the protection of intestinal epithelium, we tested the influence of TFF3 in a murine Toxoplasma gondii-induced ileitis model. Surprisingly, TFF3KO mice showed a reduced immune response in the ileum when compared to wild-type animals. Interleukin-12 and interferon-γ expression levels as well as the number of CD4+ lymphocytes were reduced in the infected TFF3KO mice. These effects were in line with the trend of elevated parasite levels in the ileum. Moreover, TFF1 expression was upregulated in the spleen of infected mice. These initial results indicate that TFF3 is involved in the immune pathology of T. gondii infection-induced intestinal inflammation. Thus far, the mechanisms of how TFF3 influences the immune response are not fully understood. Further studies should identify if TFF3 affects mucus sensing of dendritic cells and how TFF3 is involved in regulating the immune response as an intrinsic secretory peptide of immune cells.
We used single-cell gel electrophoresis (SCGE) to detect the integrity of sperm DNA of the teleost large yellow croaker, Pseudosciaena crocea, cryopreserved with Cortland solution and a range of 5% to 30% DMSO concentrations in order to test how sperm cryopreservation affected the DNA stability of nuclei. Electrophoresis was conducted for 60 min at 130 mA and 15 V. The comet images were analyzed with software CometScore 1.5, and parameters such as comet length, tail length and percentage DNA in the tail were obtained. Then the comet rate and damage coefficient were calculated. Results demonstrated that there were no significant differences in motility, comet rate and damage coefficient between fresh sperm and cryopreserved sperm stored in 5%, 10%, 15% and 20% DMSO, while the sperm cryopreserved with 25% and 30% DMSO had a lower motility, higher comet length and damage coefficients than those of fresh sperm. There was a positive correlation between comet rate of cryopreserved sperm and the concentration of DMSO. Our results demonstrate that toxicity of the cryoprotectant is the main cause of DNA damage in cryopreserved sperm nuclei.