ABSTRACT
The biocompatibility of nanomaterials has attracted much attention. Graphene oxide (GO) is a nanomaterial widely used in biomedicine, but its toxicity can not be ignored. In this study, the effect of GO on the blood system (the hemolysis rate, the fragility of erythrocyte, and acetylcholinesterase activity) was systematically investigated. The results showed that the hemolysis rate of erythrocytes was lower than 8% when the GO concentration was below 100 μg/mL (P5 μm (LGO) increased the activity of acetylcholinesterase by 42.67% (P<0.05). Then molecular dynamics simulation was used to study how GO interacted with acetylcholinesterase and increased its activity. The results showed that GO was attached to the cell membrane, thus may provide an electronegative environment that helps the hydrolysate to detach from the active sites more quickly so as to enhance the activity of acetylcholinesterase.
Subject(s)
Acetylcholinesterase , Erythrocytes , Graphite , NanostructuresABSTRACT
Motor imagery (MI) is an important paradigm of driving brain computer interface (BCI). However, MI is not easy to control or acquire, and the performance of MI-BCI depends heavily on the performance of the subjects' MI. Therefore, the correct execution of MI mental activities, ability evaluation and improvement methods play important and even critical roles in the improvement and application of MI-BCI system's performance. However, in the research and development of MI-BCI, the existing researches mainly focus on the decoding algorithm of MI, but do not pay enough attention to the above three aspects of MI mental activities. In this paper, these problems of MI-BCI are discussed in detail, and it is pointed out that the subjects tend to use visual motor imagery as kinesthetic motor imagery. In the future, we need to develop some objective, quantitatively visualized MI ability evaluation methods, and develop some effective and less time-consumption training methods to improve MI ability. It is also necessary to solve the differences and commonness of MI problems between and within individuals and MI-BCI illiteracy to a certain extent.
Subject(s)
Humans , Algorithms , Brain-Computer Interfaces , Electroencephalography , Imagery, Psychotherapy , ImaginationABSTRACT
A comprehensive analytical method based on ultra performance liquid chromatography tandem mass spectrometry has been developed for the simultaneous determination of 16 carcinogenic and allergenous dye stuffs (acid red 26, basic red 9, disperse blue 1, acid violet 49, disperse blue 3, solvent yellow 1, dispersed blue 106, disperse orange 3, disperse yellow 3, basic violet 1, basic violet 3, disperse red 1, solvent yellow 3, disperse blue 124, solvent yellow 2 and disperse orange 37).Various toy samples, including textile, leath er, paper, wood, balloon, modeling clay, limitation tattoo and aqueous liquid, were extracted under ultrason ication.Qualitative and quantitative analysis was carried out for the analyte under the MRM mode after the chromatographic separation on Waters ACQUITY UPLC BEH C_(18)(50 mm x 2.1 mm, 1.7 μm) column.The limits of quantitation(LOQ) for the 16 dyestuffs were in the range of 1.0-8.0 μg/kg.The mean recoveries at the three spiked levels of 5-100 μg/kg were 81.3%-98.6%, with the intra-day precision less than 11% and the inter-day precision less than 14%.The method is accurate, rapid, sensitive, and adapt to the inspec tion of the 16 dyestuffs in toys.
ABSTRACT
A comprehensive analytical method based on solid phase extraction-isotope dilution-gas chromatography tandem mass spectrometry has been developed for the determination of musk xylene in cosmetics. Various cosmetic samples, including cream, lotion, powder, shampoo and lipstick, were extracted under ultrasonication. The extract was centrifuged, and the upper solution was concentrated by rotary evaporator. The reconstructed solution was then cleaned up by Sep-Pak Silica solid phase extraction cartridge. Qualitative and quantitative analysis was carried out under the MRM mode after the chromatographic separation on DB-5 MS(30 m×0.25 mm, 0.25 μm) capillary column. The limit of quantitation(LOQ) for musk xylene was 5 μg/kg. The mean recoveries at the three spiked levels of 5-50 μg/kg were 81.1%-86.9%, with the intra-day precision less than 10% and the inter-day precision less than 12%. The method is accurate, rapid, sensitive and adapt to the inspection of musk xylene in cosmetics.