Systematic Dynamic Effects in Multiple Impact Pairs and Distributed Factors

In this paper in general the dynamic effects are considered and described, caused by different stand-ing waves in discrete and distributed systems with impacts and other strongly positional non-linear fac-tors, introduction of which in the models of me-chanical objects is dictated by the necessity to con-sider processes, accompanied with impacts of me-chanical subsystems of different nature.     

一类高阶中立型时滞微分方程的振动性

用不同于已有文献的方法研究了一类高阶中立型微分方程,本文不需要条件f∞t0Q(s)ds=∞,获得了这类方程振动性的几个新的结果.     

Effect of microcystin-LR on protein phosphatase 2A and its function in human amniotic epithelial cells

Due to their toxicity, the increased distribution of microcystins (MCs) has become an important worldwide problem. MCs have been recognized as inhibitors of protein phosphatase 2A (PP2A) through their binding to the PP2A catalytic subunit. However, the exact mechanism of MC toxicity has not been elucidated, especially concerning the cellular response and its autoregulation. To further dissect the role of PP2A in MC-induced toxicity, the present study was undertaken to determine the response of PP2A in human amniotic epithelial (FL) cells treated with microcystin-LR (MCLR), one of the MC congeners. The results show that a low-dose treatment of MCLR in FL cells for 6 h induced an increase in PP2A activity, and a high-dose treatment of MCLR for 24 h decreased the activity of PP2A, as expected. The increased mRNA and protein levels of the PP2A C subunit may explain the increased activity of PP2A. Furthermore, MCLR altered microtubule post-translational modifications through PP2A. These results further clarify the underlying mechanism how MCLR affects PP2A and may be helpful for elucidating the complex toxicity of MCLR.     

��It depends on what science teacher you got��: urban science self-efficacy from teacher and student voices

In the United States today, urban schools serve the majority of high-poverty and high minority populations including large numbers of Hispanic students. While many Hispanic students perform below grade level in middle school science, the science teaching community as a whole is lacking elements of diversity as teachers struggle to meet the needs of all learners. Researchers have recognized that science teacher effectiveness, one consequence of self-efficacy among teachers, is associated with future science achievement and science-related careers of their students. This qualitative study explores how three science teachers’ effectiveness in the classroom impacts students’ science self-efficacy beliefs at one urban middle school. Hispanic students were the focus of this investigation due to demographics and history of underperformance within this district. Teachers’ perspectives, as well as outside observer evaluations of instructional strategies and classroom climates were triangulated to explore dynamics that influence students’ interests and motivation to learn science using a framework to link teachers’ sense of efficacy (focusing on student outcomes). Findings suggest the impact teacher effectiveness can have on student outcomes, including strengthened student science self-efficacy and increased science achievement. Building awareness and support in teachers’ sense of efficacy, as well as developing respectful and supportive relationships between educator/facilitator and pupil during the transition to middle school may construct permanence and accomplishment for all in science.     

A Comprehensive Analysis of High School Genetics Standards: Are States Keeping Pace with Modern Genetics?

Science education in the United States will increasingly be driven by testing and accountability requirements, such as those mandated by the No Child Left Behind Act, which rely heavily on learning outcomes, or "standards," that are currently developed on a state-by-state basis. Those standards, in turn, drive curriculum and instruction. Given the importance of standards to teaching and learning, we investigated the quality of life sciences/biology standards with respect to genetics for all 50 states and the District of Columbia, using core concepts developed by the American Society of Human Genetics as normative benchmarks. Our results indicate that the states' genetics standards, in general, are poor, with more than 85% of the states receiving overall scores of Inadequate. In particular, the standards in virtually every state have failed to keep pace with changes in the discipline as it has become genomic in scope, omitting concepts related to genetic complexity, the importance of environment to phenotypic variation, differential gene expression, and the differences between inherited and somatic genetic disease. Clearer, more comprehensive genetics standards are likely to benefit genetics instruction and learning, help prepare future genetics researchers, and contribute to the genetic literacy of the U.S. citizenry.     

倾斜金标试纸图像的线宽测量方法

基于显微图像的金标试纸条测试线线宽参数的测量方法具备操作方便、测量速度快、分辨率高等优点,然而图像采集系统采集到的金标试纸条的显微图像不可避免地会发生倾斜,这为后续的图像分割和参数测量带来了困难,因此需要对倾斜的金标试纸条显微图像进行校正。根据霍夫变换法和最小二乘法在直线检测中的优点和适用条件,拟采用一种结合霍夫变换法和最小二乘法的直线检测算法来求得金标试纸条图像的边缘线和边缘线的倾斜角度参数,并采用图像旋转变换算法实现对原图像的倾斜校正。实验表明,所采用的倾斜校正算法具备计算量小、占用内存小、校正精度高的优点,通过倾斜校正可以准确测量倾斜金标试纸图像的线宽参数。     

Cloning and efficient expression of <Emphasis Type="Italic">Bacillus sp.</Emphasis> BH072 <Emphasis Type="Italic">tasA</Emphasis> gene in <Emphasis Type="Italic">Escherichia coli</Emphasis>

The Bacillus strain BH072 isolated from a honey sample showed strong antifungal activity against phytopathogen. Gene cloning test demonstrated that the strain had a tasA gene encoding an antifungal TasA protein. Although the wild strain simultaneously produced various antifungal substances, only the physicochemical property and antifungal activity of TasA protein were unclear due to the difficulty in extraction. In this study, tasA gene encoding the protein from Bacillus sp. BH072 was amplified by using the polymerase chain reaction (PCR) method and cloned into pET 28a (+) vector, and then expressed in host cells Escherichia coli BL21 (DE3). The expressed proteins were collected by centrifugation and ultrasonic treatment, and then purified by using nickel-nitrilotriacetic acid (Ni-NTA) metal affinity column and dialysis methods. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) test showed that an expected protein band appeared with a size of 31 kDa. The expressed products possessed antifungal activity against the phytopathogenic indicator strain Botrytis cinerea. A genetically engineered strain tasA of E. coli was established in this study which can efficiently express Tas A protein.     

文化创意产业视域下的上海艺术设计高端人才培养

基于调查数据,探讨了2012、2013年上海文化创意产业结构、发展规模以及该类技能人才占有情况,分析了上海本专科院校艺术设计类技能人才培养建设现状,提出了从培养单纯掌握专业技法的工具型人才向培养熟悉完整艺术设计流程的综合职业人才转变的人才培养思路和以高端人才为导向的多元化教育模式与个性化人才培养方案。     

Four Cases of Transfer Leading to Accomplishment

Throughout their lives, individuals accumulate and apply lessons learned from instruction and experience. It is unclear how they transfer these lessons to become accomplished in their fields. In this exploratory study, we develop grounded hypotheses about the relationship of transfer to accomplishment. Selected individuals told stories about what they learned that influenced their major accomplishments, their sources, and timing. Findings indicate that individuality is magnified on the road to accomplishment, although shared lessons were evident. Attitudes and values, adopted and applied, seemed to play a special role in the passage from transfer to accomplishment.