RESUMO
Nowadays, augmented reality (AR) is becoming more and more prevalent and used in many fields, including education. Previous studies have reported the positive effect of AR to advocate the use of AR in the classroom. However, it is unclear whether such a positive effect can be reported for any student. In this study, we recruited students from a Chinese vocational college. Due to the peculiar conditions in China, students in vocational colleges may have weaker learning abilities and worse academic performance than students in research universities. Furthermore, the sex and grade of students were considered. We conducted a three-stage experiment for the PPT-based group and the AR-based group separately. We taught the students the orthographic projection, a lesson from the Engineering Drawing course, which is widely learned by students who majored in architecture. The students' academic performances were rated prior to class, right after class, and 1-week after class, through a direct examination at three stages. We found the inefficiency of AR for students in vocational colleges. The interaction effect between sex and grade of students was also reported. Students undergoing AR-based teaching could not perform better or even worse than students undergoing PPT-based teaching. We recommended that the teachers should consider whether to use AR in the classroom based on the characteristics of students.
Assuntos
Realidade Aumentada , Humanos , Educação Vocacional , População do Leste Asiático , Aprendizagem , EstudantesRESUMO
Chemical derivatization is a very promising technique for improving analysis of peptides by mass spectrometry (MS). Thereinto, development of novel tags compatible with MS and/or MS/MS has always been the focus point of study. In this review, the recent reported tags for derivatization of thiol groups of cysteine, carboxyl groups, and amino groups on peptides as well as peptides with post-translational modifications (PTMs) are summarized. Moreover, the tags used for derivatization of glycans or oligosaccharides released from glycoproteins are also reviewed.
Assuntos
Glicoproteínas/análise , Peptídeos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Cisteína/química , Cisteína/metabolismo , Glicoproteínas/química , Glicoproteínas/metabolismo , Estrutura Molecular , Oligossacarídeos/química , Oligossacarídeos/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo , Processamento de Proteína Pós-Traducional , Reprodutibilidade dos TestesRESUMO
A new method was developed for simultaneous determination of cypermethrin and permethrin residues in pear juice with ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) and gas chromatography-flame ionization detection (GC-FID). 3.5 mL of methanol (dispersant) and 30 microL of C(2)Cl(4) (extractant) were injected into 5.0 mL of pear juice sample and then emulsified by ultrasound for 2.0 min to forming the cloudy solution. Under the optimum condition, the enrichment factors for cypermethrin and permethrin were 344 and 351 fold respectively. Good linearity was observed in a range of 0.009-1.52 microg g(-1) with the correlation coefficient (r(2))>or=0.9993. The limits of detection (LODs) were 3.1 and 2.2 microg kg(-1) for cypermethrin and permethrin, respectively (S/N=3). The recoveries of the method evaluated at three spiked levels were in the range of 92.1%-107.1%. The repeatability evaluated as intra-day and inter-day precision (RSDs) were less than 4.0% (n=5). The developed method was successfully applied to determine the two pesticide residues in different pear juice samples.