甄别多项选择题考试中答案抄袭的不同方法的比较

在美国,各个考试公司都会用不同的统计方法来检测考试中的舞弊现象。本文研究了两个检测舞弊的指数:基于经典考试理论的g2指数和基于项目反应理论的w指数。文章模拟了四种真实测试情形中常见的抄袭模式和几个可能影响指数的变量,研究结果表明,对于g2和w指数,在各种情形下,按照有偏差的估计参数以及真实参数计算出来的第一类错误率都是类似的,并且较低。因此,用有偏差的估计参数来计算g2和w指数不会增加将被抄袭者误认为抄袭者的可能性。而基于有偏差的估计参数的g2和w指数,只有在抄袭题目百分比较高且测试长度较长的情况下,才可能实现较低的第二类错误率。当抄袭题目百分比较低时,即便使用真实参数,g2和w指数都会造成较高的第二类错误率。     

Effect of folic acid and vitamin B<Subscript>12</Subscript> administration on phenytoin induced toxicity in rats

Folic acid and vitamin B₁₂ are very important vitamins needed for normal cellular metabolic activities. The effects of folic acid and vitamin B₁₂ on liver integrity of growing Wistar albino rats following therapeutic dose of phenytoin administration were investigated. The activities of serum AST, ALT, ALP were investigated. Serum total protein level and lipid profile were also measured as indices of biochemical changes. The ingestion of phenytoin alone in rats significantly reduced serum protein while AST, ALT activities incresed as compared to the control (P<0.05). Supplementation of phenytoin with oral administration of 70microgram/kg body wt of folic acid resulted in a significant reversal in serum total protein and suppression in serum AST and ALT activities. Vitamin B₁₂ supplementation did not afford any significant protection against the effect of phenytoin ingestion but rather phenytoin toxicity was exacerbated in this study. However, the combined effects of vitamin B₁₂ and folic acid ameliorated the effects of phenytoin on serum enzymes of experimental rats. The effect of combination of phenytoin with folic acid or folic acid and vitamin B₁₂ is an interesting finding. Supplementation of phenytoin with folic acid or combination of these vitamins may be recommended for the purpose of ameliorating the adverse biochemical changes which are associated with phenytoin therapy. Further work is ongoing to help elucidate the effects of phenytoin and these vitamins on oxidative stress inducing mechanism.     

中心镇建设的动态运行机制——源自普惠制（GSP）理念的安排

中心镇是我国城镇化建设整体进程中的重要环节和中转平台.研究基于竞争性运行主线,借鉴源自国际贸易中普惠制待遇的理念,构建了“选取—培育—提升—毕业”整套运行机制,设计了动态管控导向下的中心镇建设路线图.     

DNA combing on low-pressure oxygen plasma modified polysilsesquioxane substrates for single-molecule studies

Molecular combing and flow-induced stretching are the most commonly used methods to immobilize and stretch DNA molecules. While both approaches require functionalization steps for the substrate surface and the molecules, conventionally the former does not take advantage of, as the latter, the versatility of microfluidics regarding robustness, buffer exchange capability, and molecule manipulation using external forces for single molecule studies. Here, we demonstrate a simple one-step combing process involving only low-pressure oxygen (O₂) plasma modified polysilsesquioxane (PSQ) polymer layer to facilitate both room temperature microfluidic device bonding and immobilization of stretched single DNA molecules without molecular functionalization step. Atomic force microscopy and Kelvin probe force microscopy experiments revealed a significant increase in surface roughness and surface potential on low-pressure O₂ plasma treated PSQ, in contrast to that with high-pressure O₂ plasma treatment, which are proposed to be responsible for enabling effective DNA immobilization. We further demonstrate the use of our platform to observe DNA-RNA polymerase complexes and cancer drug cisplatin induced DNA condensation using wide-field fluorescence imaging.     

Emotional labor and burnout among Turkish primary school teachers

Emotions play a critical role in teaching, especially in primary schools. Teachers have to manage their feelings in order to sustain a positive classroom climate. Managing feelings as a requirement of work is called emotional labor, which is a relatively new area of research in teaching. The main aim of this research was to investigate the type of emotional labor strategies Turkish primary school teachers often use and whether emotional labor is a predictor of burnout for primary teachers in a Turkish context. Also, the authors explore if there is a significant variation in emotional labor in terms of gender and school type (public/private). A survey was conducted with the participation of 370 primary school teachers from Ankara, Turkey. Results indicated that Turkish primary school teachers mostly engage in genuine emotions in their relationships with students. Female teachers use deep and surface acting strategies more often than males. Also, private school teachers were found to use deep acting strategies and display genuine emotions more often than public school teachers. Finally, it was found that emotional labor is a significant predictor of burnout among Turkish primary school teachers.     

Organizational realignment case study: Adding value by analyzing performance

The U.S. Navy is a global organization with an annual budget in excess of $140 billion and employs roughly 330, 000 sailors. A multilevel adaptation of the human performance model was applied to look across organizations for functional areas where efficiencies could be gained by standardizing business practices and cooperating across organizational boundaries. The resulting 17‐to‐1 return on investment is attributed to the process of working through the model with a team of executive stakeholders.     

Reliability and validity of a modified 3-minute all-out swimming test in elite swimmers

Critical speed (CS) testing is useful in monitoring training in swimmers, however, completing a series of time trials (TTs) regularly is time-consuming. The 3-minute test may be a solution with positive initial findings. This investigation examined whether a modified 3-minute test (12?×?25?m) could assess CS and supra-CS distance capacity (D’) in swimmers. A series of 12?×?25?m intervals were completed unpaced at maximal effort, interspersed with 5?s rest periods. The model speed?=?a e^{b t}?+?c was fitted to the data and integrated to calculate D’. The slowest two of the last four efforts were averaged to calculate CS. To assess reliability, 15 highly trained swimmers (9 females, 6 males) completed the 12?×?25?m twice within 72?h. Four measures were deemed reliable: peak velocity (0.01?m?s^?1; 0.5%, typical error and % coefficient of variation), CS (0.02?m?s^?1; 1.2%), D’ (1.22?m; 5.7%) and drop off % (0.70% points; 4.5%). To assess criterion validity, 21 swimmers (9 from reliability, 12 other) completed two competition races within 2 weeks of a 12?×?25?m in the same stroke. Traditional CS and D’ measures were calculated from competition performances (TT method). TT CS and 12?×?25?m CS were highly correlated (adj. R²?=?0.92, p?D’ values were moderately correlated (adj. R²?=?0.60, p?D’ accurately. The 12?×?25?m all-out swimming test is a reliable method for assessing CS and D’ in swimmers, however, the validity of D’ requires further investigation.     

Participation in technology standards development: A decision model for the information and communications technology (ICT) industry

This study presents a framework to guide managers in the ICT industry in assessing the factors that inform the decision to participate in the development of technology standards. Using multi-criteria decision analysis and judgment data from panels of experts, a robust model is developed that comprehends the essential criteria and outcomes within the context of computer interconnect technologies. The resultant, generalizable model is validated against the case of the extant Universal Serial Bus (USB) interconnect standard and found to be congruent with the assessment of the experts.