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891.
How can be explained that early literacy and numeracy share variance? We specifically tested whether the correlation between four early literacy skills (rhyming, letter knowledge, emergent writing, and orthographic knowledge) and simple sums (non-symbolic and story condition) reduced after taking into account preschool attention control, short-term memory, speed of processing, visual-spatial skills, vocabulary, and shared book reading. 228 Dutch native preschoolers (mean age 54.25; SD = 2.12 months) participated. The results revealed that 1) all literacy skills were related to sums (non-symbolic and story condition), 2) rhyming was the strongest predictor of non-symbolic sums, and letter knowledge of sums in story context, 3) visual-spatial skills explained part of the shared variance in the non-symbolic condition and visualspatial skills, vocabulary and short-term memory explained part of the shared variance in sums in story context. Implications for the preschool curriculum and early interventions are discussed. 相似文献
892.
Niklas M. Gericke Mariana Hagberg Vanessa Carvalho dos Santos Leyla Mariane Joaquim Charbel N. El-Hani 《Science & Education》2014,23(2):381-416
The aim of this paper is to investigate in a systematic and comparative way previous results of independent studies on the treatment of genes and gene function in high school textbooks from six different countries. We analyze how the conceptual variation within the scientific domain of Genetics regarding gene function models and gene concepts is transformed via the didactic transposition into school science textbooks. The results indicate that a common textbook discourse on genes and their function exist in textbooks from the different countries. The structure of science as represented by conceptual variation and the use of multiple models was present in all the textbooks. However, the existence of conceptual variation and multiple models is implicit in these textbooks, i.e., the phenomenon of conceptual variation and multiple models are not addressed explicitly, nor its consequences and, thus, it ends up introducing conceptual incoherence about the gene concept and its function within the textbooks. We conclude that within the found textbook-discourse ontological aspects of the academic disciplines of genetics and molecular biology were retained, but without their epistemological underpinnings; these are lost in the didactic transposition. These results are of interest since students might have problems reconstructing the correct scientific understanding from the transformed school science knowledge as depicted within the high school textbooks. Implications for textbook writing as well as teaching are discussed in the paper. 相似文献
893.
The physics behind the game of billiards is rather well understood as is our grasp of classical mechanics. We present here a mathematical explanation of why slice shots are more difficult than direct shots. Despite a large number of treatises dedicated to the study of physics of billiards, it appears that the simple explanation has escaped our attention until now. We show that high impact-parameter shots impart a larger angular spread to the object ball, compared to head-on shots. The effect can be understood in terms of a non-linear relationship between the impact parameter and the scattering angle, and the fact that a real-world pool player does not have a perfect cue ball control; in other words, the impact parameter distribution is not a delta function, but has a finite spread. To keep the mathematics simple and not to obscure the underlying physical principles our treatment ignores the ball’s spin, friction, and other well-known effects in the game of pool. 相似文献
894.
Ines Ben Chobba Amine Elleuch Imen Ayadi Lamia Khannous Ahmed Namsi Frederique Cerqueira Noureddine Drira Néji Gharsallah Tatiana Vallaeys 《Journal of Zhejiang University. Science. B》2013,14(12):1084-1099
Endophytic flora plays a vital role in the colonization and survival of host plants, especially in harsh environments, such as arid regions. This flora may, however, contain pathogenic species responsible for various troublesome host diseases. The present study is aimed at investigating the diversity of both cultivable and non-cultivable endophytic fungal floras in the internal tissues (roots and leaves) of Tunisian date palm trees (Phoenix dactylifera). Accordingly, 13 isolates from both root and leaf samples, exhibiting distinct colony morphology, were selected from potato dextrose agar (PDA) medium and identified by a sequence match search wherein their 18S–28S internal transcribed spacer (ITS) sequences were compared to those available in public databases. These findings revealed that the cultivable root and leaf isolates fell into two groups, namely Nectriaceae and Pleosporaceae. Additionally, total DNA from palm roots and leaves was further extracted and ITS fragments were amplified. Restriction fragment length polymorphism (RFLP) analysis of the ITS from 200 fungal clones (leaves: 100; roots: 100) using HaeIII restriction enzyme revealed 13 distinct patterns that were further sequenced and led to the identification of Alternaria, Cladosporium, Davidiella (Cladosporium teleomorph), Pythium, Curvularia, and uncharacterized fungal endophytes. Both approaches confirmed that while the roots were predominantly colonized by Fusaria (members of the Nectriaceae family), the leaves were essentially colonized by Alternaria (members of the Pleosporaceae family). Overall, the findings of the present study constitute, to the authors’ knowledge, the first extensive report on the diversity of endophytic fungal flora associated with date palm trees (P. dactylifera). 相似文献
895.
Dina N. Kovarik Davis G. Patterson Carolyn Cohen Elizabeth A. Sanders Karen A. Peterson Sandra G. Porter Jeanne Ting Chowning 《CBE life sciences education》2013,12(3):441-459
We investigated the effects of our Bio-ITEST teacher professional development model and bioinformatics curricula on cognitive traits (awareness, engagement, self-efficacy, and relevance) in high school teachers and students that are known to accompany a developing interest in science, technology, engineering, and mathematics (STEM) careers. The program included best practices in adult education and diverse resources to empower teachers to integrate STEM career information into their classrooms. The introductory unit, Using Bioinformatics: Genetic Testing, uses bioinformatics to teach basic concepts in genetics and molecular biology, and the advanced unit, Using Bioinformatics: Genetic Research, utilizes bioinformatics to study evolution and support student research with DNA barcoding. Pre–post surveys demonstrated significant growth (n = 24) among teachers in their preparation to teach the curricula and infuse career awareness into their classes, and these gains were sustained through the end of the academic year. Introductory unit students (n = 289) showed significant gains in awareness, relevance, and self-efficacy. While these students did not show significant gains in engagement, advanced unit students (n = 41) showed gains in all four cognitive areas. Lessons learned during Bio-ITEST are explored in the context of recommendations for other programs that wish to increase student interest in STEM careers. 相似文献
896.
Cathryn Kabacoff Vasudha Srivastava Douglas N. Robinson 《CBE life sciences education》2013,12(3):410-418
Internships are an effective way of connecting high school students in a meaningful manner to the sciences. Disadvantaged minorities have fewer opportunities to participate in internships, and are underrepresented in both science, technology, engineering, and mathematics majors and careers. We have developed a Summer Academic Research Experience (SARE) program that provides an enriching academic internship to underrepresented youth. Our program has shown that to have a successful internship for these disadvantaged youth, several issues need to be addressed in addition to scientific mentoring. We have found that it is necessary to remediate and/or fortify basic academic skills for students to be successful. In addition, students need to be actively coached in the development of professional skills, habits, and attitudes necessary for success in the workplace. With all these factors in place, these youths can become better students, compete on a more level playing field in their internships, and increase their potential of participating actively in the sciences in the future. 相似文献
897.
Sister M. Claire Madeleine S.N.J.M. 《College Teaching》2013,61(1):31-33
The authors explore how and to what extent students use their textbooks. Data was collected through a survey regarding when reading is primarily done, how the textbook is used for studying, and which specific study strategies the students used. The results indicate that students know it is important to read, know the professor expects them to read, and know it will impact their grade, yet most students still do not read the textbook. Finally, we also examine what students feel would motivate them to increase their usage of the textbook. 相似文献
898.
In interpersonal relationships characterized by aggression, the negotiation of conflict is especially significant. The present study examined the conflict management strategies used by 31 individuals who had experienced verbal and/or physical aggression during conflicts with their partners. Sillars’ (1986) conflict tactics coding system was used as a framework to analyze 960 pages of transcribed data. The results of this deductive content analysis indicated that the participants reported using primarily Distributive conflict strategies. Analytic induction was also used to interpret nonverbal forms of conflict management, revealing three common tactics: crying, nonverbal avoidance, and aggression. Implications for using these conflict strategies in interpersonal relationships characterized by aggression are discussed. 相似文献
899.
This study explored the relationship between effective instructor behavior—instructor confirmation—and a potentially negative student behavior—instructional dissent. Previous studies demonstrate that student characteristics provide a limited explanation for how students express dissent (e.g., Goodboy & Myers, 2012). Thus, scholars have begun to investigate the influence of instructor behaviors along with student characteristics to understand why students express dissent (LaBelle, Martin, & Weber, 2013). This study revealed that instructor confirmation negatively related to expressive and vengeful dissent, but not rhetorical dissent. Further, the three dimensions of instructor confirmation functioned differently in accounting for variance in expressive and vengeful dissent. Future research should build towards a model of instructional dissent model that reflects the unique characteristics of the instructional context and modifiable instructor behaviors. 相似文献
900.
Vito N. Silvestri 《Communication Studies》2013,64(3):178-186
Roosevelt urged war preparation and active retaliation when neutral policies prevailed and when the mood of the nation was one of noninvolvement abroad. 相似文献