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141.
142.
谭本超 《安顺师范高等专科学校学报》2015,17(2)
欠发达地区新建地方高校的大学生英语口语学习始终难以克服本土化困境,如语言环境差、高中英语学习的惯性、特殊的心理障碍、教育评价系缺失等不利因素一直制约着他们英语口语学习成效的提高.大学生们只有针对这些在在的问题,有针对性地加以解决,才能提高英语口语的交际能力. 相似文献
143.
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. 相似文献
144.
以过量表达 AtHsfAla 及 AtHsfAla 基因沉默的转基因植株为材料,通过控制土壤水分进行干旱处理,结果显示,过量表达型干旱处理后的存活率最大,而基因沉默型最小,表明 AtHsfA1a 能增强植物的抗旱性。为了从生理水平研究 AtHsfA1a 提高抗旱性的机制,研究发现过量表达型的叶片相对含水量和叶绿素含量最高,而沉默型最低。不同基因型植株的 H2 O2和 MDA 的含量正好相反,说明 AtHsfA1a 通过保护细胞膜而减小细胞所受氧化伤害来提高抗旱能力。 相似文献
145.
Daniel Tan Lei Shek Florence Ka Yu Wu Wen Yu Chai 《Assessment & Evaluation in Higher Education》2015,40(8):1017-1031
Under the new four-year undergraduate programme, a general education framework titled ‘General University Requirements’ (GUR) has been developed and implemented since 2012/2013 at Hong Kong Polytechnic University (PolyU). To evaluate the implementation and effectiveness of the GUR in its first year, focus group interviews with students were carried out. In 13 focus groups, 62 first-year students from eight faculties/schools who took GUR subjects in 2012/2013 academic year were interviewed by trained researchers. Results showed that students generally had good perceptions of the GUR in terms of the subject content, teaching methods and the overall effectiveness of the subjects. The interactive teaching and learning initiatives adopted in GUR subjects were particularly appreciated, although students expressed minor concerns on the administration of GUR subjects. The results suggest that the first-year implementation of the GUR at PolyU was generally smooth and successful from the perspectives of the students. 相似文献
146.
147.
The current study took a person-centered approach to examine the heterogeneity of changes in children’s emotions and persistence during a goal-blocking task and examined how different profiles of emotions and persistence related to children’s self-regulation. Children’s anger, sadness, and persistence were rated in a goal-blocking task in toddlerhood (T1; N = 140, 72 boys, Mage = 2.67 years, 90.7% White) and preschool (T2). Children’s self-regulation, specifically sustained attention and engagement, was assessed at T1, T2, and early school-age (T3) from 2005 to 2012. Growth mixture modeling revealed two classes of children at T1 and three classes at T2 with different patterns of anger, sadness, and persistence. Children’s classification at T2, but not T1, significantly predicted their sustained attention and engagement both concurrently and longitudinally. 相似文献
148.
对外贸函电语篇的分析有助于理解外贸信函的写作方法,更好地开展信函沟通。本文从语篇功能的主述位结构、信息结构及衔接三个方面对外贸函电的语篇功能进行分析,探讨外贸函电的语法和词汇运用。 相似文献
149.
Photocatalytic water purification using visible light is under intense research in the hope to use sunlight efficiently, but the conventional bulk reactors are slow and complicated. This paper presents an integrated microfluidic planar reactor for visible-light photocatalysis with the merits of fine flow control, short reaction time, small sample volume, and long photocatalyst durability. One additional feature is that it enables one to use both the light and the heat energy of the light source simultaneously. The reactor consists of a BiVO4-coated glass as the substrate, a blank glass slide as the cover, and a UV-curable adhesive layer as the spacer and sealant. A blue light emitting diode panel (footprint 10 mm × 10 mm) is mounted on the microreactor to provide uniform irradiation over the whole reactor chamber, ensuring optimal utilization of the photons and easy adjustments of the light intensity and the reaction temperature. This microreactor may provide a versatile platform for studying the photocatalysis under combined conditions such as different temperatures, different light intensities, and different flow rates. Moreover, the microreactor demonstrates significant photodegradation with a reaction time of about 10 s, much shorter than typically a few hours using the bulk reactors, showing its potential as a rapid kit for characterization of photocatalyst performance. 相似文献
150.
通过《谷梁传》十五则叙事文字与《左传》《公羊传》同题故事逐一比较可以发现,有谷梁氏优于左氏、公羊氏者,有三家各有千秋者,有谷梁氏不如二氏者.谷梁氏多数故事不如左氏,少数互有短长.谷梁氏叙事与公羊氏相差无几.出现上述差异的原因在于,谷梁氏、公羊氏是经学家,重在解释《春秋》经义,故事只是为释义的补充而已,因而忽视叙事的完整性和生动性.左氏是史学家兼史传文学家,长于叙事,重视细节的真实性和情节的完整性,解释《春秋》经义只是偶尔为之. 相似文献