Teachers have been paying more attention to oral English teaching in junior high school than ever before. Generally, teachers focus on teaching oral English in class, where they give preeminence to creating an environ...Teachers have been paying more attention to oral English teaching in junior high school than ever before. Generally, teachers focus on teaching oral English in class, where they give preeminence to creating an environment in the classroom which approximates to the"real-life"communicative use of language (Yang Chaochun & Cheng Lian 2005). However, there are some limits teaching oral English in class. This essay puts forwards to provide input during the break time for students to acquire oral English unconsciously in junior high school to make up for the insufficiency.展开更多
AIM：To investigate the association between tear film break up time（TBUT）and blinking interval in visual display terminal（VDT）users.METHODS：Nine hundred and thirty VDT users underwent dry eye testing,and function...AIM：To investigate the association between tear film break up time（TBUT）and blinking interval in visual display terminal（VDT）users.METHODS：Nine hundred and thirty VDT users underwent dry eye testing,and functional visual acuity（FVA）test.The blinking interval during FVA was compared with TBUT.Subjects with longer blinking interval than TBUT were considered as unstable tear film.Logistic regression analysis revealed the risk factors for unstable tear group.RESULTS：Among 930 workers,858 subjects（92.3%）participated in this study.Almost 80% of the subjects were categorized into the unstable tear group.Unstable tear group has significantly lower Schirmer values and TBUT（17.5±11.6 vs 21.1±11.5 mm,3.7±2.6 vs 5.7±2.7s,both P〈0.001）.There were no significant differences in epithelial staining or severity of symptoms.Logistic regression showed that over 40y was a risk for being unstable tear group[odds ratio（OR）=1.53;95%confidence interval（CI）=1.06-2.20].Contact lens use was protective factor for being in the unstable tear group（OR=0.37;95%CI=0.26-0.53）.CONCLUSION：Subjects with shorter TBUT than blinking interval are prevalent among VDT users.Subjects over the age of 40 shows an increased risk for unstable tear film.展开更多
The space-time evolution of a given density perturbation in cold homogeneous electron- positron-ion plasma is investigated with an assumption of infinitely massive ions by employing a numerical calculation method. The...The space-time evolution of a given density perturbation in cold homogeneous electron- positron-ion plasma is investigated with an assumption of infinitely massive ions by employing a numerical calculation method. The phase-mixing time and wave-breaking time can be effectively distinguished with this method. It is found that an increase of the ratio of equilibrium ion density to equilibrium electron density can attenuate plasma oscillations, leading to a delay in wave breaking. The dependence of the phase-mixing and wave-breaking times on the amplitude of the initial perturbation is also discussed.展开更多
文摘Teachers have been paying more attention to oral English teaching in junior high school than ever before. Generally, teachers focus on teaching oral English in class, where they give preeminence to creating an environment in the classroom which approximates to the"real-life"communicative use of language (Yang Chaochun & Cheng Lian 2005). However, there are some limits teaching oral English in class. This essay puts forwards to provide input during the break time for students to acquire oral English unconsciously in junior high school to make up for the insufficiency.
文摘AIM：To investigate the association between tear film break up time（TBUT）and blinking interval in visual display terminal（VDT）users.METHODS：Nine hundred and thirty VDT users underwent dry eye testing,and functional visual acuity（FVA）test.The blinking interval during FVA was compared with TBUT.Subjects with longer blinking interval than TBUT were considered as unstable tear film.Logistic regression analysis revealed the risk factors for unstable tear group.RESULTS：Among 930 workers,858 subjects（92.3%）participated in this study.Almost 80% of the subjects were categorized into the unstable tear group.Unstable tear group has significantly lower Schirmer values and TBUT（17.5±11.6 vs 21.1±11.5 mm,3.7±2.6 vs 5.7±2.7s,both P〈0.001）.There were no significant differences in epithelial staining or severity of symptoms.Logistic regression showed that over 40y was a risk for being unstable tear group[odds ratio（OR）=1.53;95%confidence interval（CI）=1.06-2.20].Contact lens use was protective factor for being in the unstable tear group（OR=0.37;95%CI=0.26-0.53）.CONCLUSION：Subjects with shorter TBUT than blinking interval are prevalent among VDT users.Subjects over the age of 40 shows an increased risk for unstable tear film.
基金supported by National Natural Science Foundation of China (Nos. 11665012 and 11247016)the Natural Science Foundation of Jiangxi Province, China (Nos. 2014ZBAB202001 and 2015ZBAB202006)
文摘The space-time evolution of a given density perturbation in cold homogeneous electron- positron-ion plasma is investigated with an assumption of infinitely massive ions by employing a numerical calculation method. The phase-mixing time and wave-breaking time can be effectively distinguished with this method. It is found that an increase of the ratio of equilibrium ion density to equilibrium electron density can attenuate plasma oscillations, leading to a delay in wave breaking. The dependence of the phase-mixing and wave-breaking times on the amplitude of the initial perturbation is also discussed.
