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21.
The purpose of this study was to investigate the relations between academic rational/irrational beliefs, academic procrastination, and time preferences to study for exams and academic achievement by using the structural equation model. The sample consisted of 281 undergraduate students who filled in questionnaires at the 7-week-long summer course. Students responded to questionnaires assessing their levels of (a) academic procrastination, (b) academic rational/irrational beliefs, and (c) time preferences to study for exams and demographic information sheet. In general, the results showed that rational academic beliefs have a direct impact on academic procrastination and time preferences to study for exams. Academic rational beliefs also have an impact on academic achievement indirectly by mediation of academic procrastination and time preferences to study for exams. The results also showed that academic procrastination has an impact on academic achievement both directly and by mediation of time preferences to study for exams. This study suggested that there is a relation between academic procrastination and rational academic beliefs, which should be addressed further in counseling intervention. Knowledge about the role of irrational academic beliefs and their relations with academic procrastination may assist school/ college counselors to develop interventions for students that suffer from delaying behaviors that negatively affect academic success.  相似文献   
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Psoriasis patients are determined to have a high ratio of coronary artery calcification. Fetuin-A and osteoprotegerin are systemic calcification inhibitors and related to vascular calcification and cardiovascular mortality. In this study we investigated the relationship between fetuin-A and osteoprotegerin levels in psoriasis patients. The study included 40 healthy volunteers and 40 psoriasis patients. Venous blood were collected from healthy volunteers and psoriasis patients in order to search the fetuin-A and osteoprotegerin levels. Disease severity were grouped as mild, moderate and severe according to psoriasis area and severity index (PASI). The relationship between fetuin-A and osteoprotegerin levels and clinical features as sex, PASI and presence of psoriatic arthritis were analyzed. Fetuin-A levels in psoriasis patients were statistically lower than the control group (p < 0.001). In serum osteoprotegerin levels, no statistically significant difference was found in two groups (p > 0.05). Serum fetuin-A and osteoprotegerin level differences were not statistically significant between patients with psoriatic arthritis history and those without. When we grouped patients in respect of their sexes fetuin-A and osteoprotegerin levels of males and females were not significantly different (p > 0.05). No correlation was detected between the ages and PASI scores and the fetuin-A and osteoprotegerin levels of patients. As a result fetuin-A levels in psoriasis patients are found to be low but not related to disease severity. In the light of our results we concluded that fetuin-A may have a role in psoriasis pathogenesis and may contribute to the calcification process developed in psoriasis.  相似文献   
23.
We demonstrate effective new methods of document ranking based on lexical cohesive relationships between query terms. The proposed methods rely solely on the lexical relationships between original query terms, and do not involve query expansion or relevance feedback. Two types of lexical cohesive relationship information between query terms are used in document ranking: short-distance collocation relationship between query terms, and long-distance relationship, determined by the collocation of query terms with other words. The methods are evaluated on TREC corpora, and show improvements over baseline systems.  相似文献   
24.
Micro-orifice based cell fusion assures high-yield fusion without compromising the cell viability. This paper examines feasibility of a dielectrophoresis (DEP) assisted cell trapping method for parallel fusion with a micro-orifice array. The goal is to create viable fusants for studying postfusion cell behavior. We fabricated a microfluidic chip that contained a chamber and partition. The partition divided the chamber into two compartments and it had a number of embedded micro-orifices. The voltage applied to the electrodes located at each compartment generated an electric field distribution concentrating in micro-orifices. Cells introduced into each compartment moved toward the micro-orifice array by manipulation of hydrostatic pressure. DEP assisted trapping was used to keep the cells in micro-orifice and to establish cell to cell contact through orifice. By applying a pulse, cell fusion was initiated to form a neck between cells. The neck passing through the orifice resulted in immobilization of the fused cell pair at micro-orifice. After washing away the unfused cells, the chip was loaded to a microscope with stage top incubator for time lapse imaging of the selected fusants. The viable fusants were successfully generated by fusion of mouse fibroblast cells (L929). Time lapse observation of the fusants showed that fused cell pairs escaping from micro-orifice became one tetraploid cell. The generated tetraploid cells divided into three daughter cells. The fusants generated with a smaller micro-orifice (diameter∼2 μm) were kept immobilized at micro-orifice until cell division phase. After observation of two synchronized cell divisions, the fusant divided into four daughter cells. We conclude that the presented method of cell pairing and fusion is suitable for high-yield generation of viable fusants and furthermore, subsequent study of postfusion phenomena.  相似文献   
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Many state and federal governments have mandated in such documents as the National Science Education Standards that inquiry strategies should be the focus of the teaching of science within school classrooms. The difficult part for success is changing teacher practices from perceived traditional ways of teaching to more inquiry‐based approaches. Arguments are often made about the effectiveness of these traditional strategies. The purpose of this study was to compare the effectiveness of the inquiry‐based approach known as the Science Writing Heuristic approach as a treatment to traditional teaching practices on students' post‐test scores in relation to students' achievement level and teacher's implementation of the approach. A mixed‐method research approach was used to analyze the teacher observational data and students' test results. The major findings of this study are that the quality of the implementation does have an impact on student performance on post‐test scores and that high‐quality implementation of the Science Writing Heuristic approach has significant advantages in closing the achievement gap within science classrooms.  相似文献   
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Much research has been done and reform is suggested relating to teachers’ implementation of student‐oriented learning environments, yet research on the role, beliefs, pedagogy, and knowledge of teachers simultaneously in classroom environments has been minimal (Kyle, 1994 Kyle, W.C. 1994. School reform and the reform of teacher education: Can we orchestrate harmony?. Journal of Research in Science Teaching, 31: 785786. [Crossref] [Google Scholar], Journal of Research in Science Teaching, 31, 785–786). This case study reports on a teacher’s perceptions, epistemology, and understandings of student‐oriented learning environments during a large project in which teachers from Grades 7 to 11 implemented an interactive‐constructivist approach in place of a traditional teacher‐oriented approach. In‐depth analysis of data revealed that the participant teacher’s perspective of a student‐centered science learning environment concerned the following: understanding of students’ prior knowledge, the importance and challenges of questioning, the teacher’s conceptual understanding of topics and unit preparation before and during the implementation, and the teacher’s motivation and problems in moving toward such an environment. There was consistency between the emerging themes and the crucial components of Simon’s Mathematics Teaching Cycle model, such as the teacher’s conceptual and pedagogical knowledge, hypothetical learning trajectory, and the teacher’s beliefs and teaching practice as argued by Haney, Czerniak, and Lumpe (1996 Haney, J., Czerniak, C. and Lumpe, A. 1996. Teacher beliefs and intentions regarding the implementation of science education reform strands. Journal of Research in Science Teaching, 33(9): 971993.  [Google Scholar], Journal of Research in Science Teaching, 33(9), 971–993) and van Driel, Beijaard, and Verloop (2001 van Driel, J.H., Beijaard, D. and Verloop, N. 2001. Professional development and reform in science education: The role of teachers’ practical knowledge. Journal of Research in Science Teaching, 38(2): 137158. [Crossref], [Web of Science ®] [Google Scholar], Journal of Research in Science Teaching, 38(2), 137–158). Further, findings of this study would help teacher education and reform planners to conduct more comprehensive studies on teachers’ perceptions about inquiry‐based teaching over the course of several years of inservice and preservice programs.  相似文献   
29.
纹理特征是图像分析的重要线索,灰度共生矩阵法提取的纹理特征具有很好的鉴别和分类能力。本文运用灰度共生矩阵分析新疆地方性肝包虫CT图像并进行特征提取,对图像进行尺寸归一、去噪和增强的预处理,计算0°,45°,90°和135°方向的能量、熵、对比度、相关性和逆差矩的均值,构成特征向量,并进行统计分析,用最大类间距法获取图像分类的主要特征,同时使用判别分析法对特征的分类能力进行评价。实验结果表明,灰度共生矩阵法提取的特征在统计分析中存在差异,最大类间距计算获得的特征能提高图像分类的准确率,一定程度上有助于对肝包虫病CT图像进行分类和检索。  相似文献   
30.
Human behaviours in organisations are closely associated with leadership styles. The main purpose of this study is to find out the relationship between teachers’ perception about multi-frame leadership orientations of principals and teachers’ emotional labour. The study is based on Bolman and Deal’s Four Frames Model, and, therefore, the Leadership Orientation Scale and Emotional Labour Scale are used. The participants of this research are 570 teachers. The teachers’ perceptions showed that school principals tend to mostly use political and structural frames. In addition, teachers consider themselves as having a high level of genuine emotions. It was also found that school principals’ leadership orientations are significant predictors of emotional labour.  相似文献   
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