白芷的核型研究及其分类意义

The present paper deals mainly with the karyotype analysis of five materials in Angelica dahurica collected in Yanbian of Jilin, Anguo of Hebei, Yuxian of Henan, Hangzhou of Zhejiang and Suining of Sichuan.  They are under the names “Dongbeidahuo”, “Qibaizhi”, “Yubaizhi”, ”Hangbaizhi” and “Chuanbaizhi” respe- ctively.  Among then “Dongbeidahuo” is a wild plant, which occurs in  northeastern China, and the others are cultivated as important crude drugs in some provinces. “Qi- Baizhi” and “Yubaizhi” have been identified as conspecific with the wild Baizhi-“Do- Ngbeidahuo” (A. dahurica) according to the external morphological features, whereas the other cultivated ones, “Hangbaizhi” and “Chuanbaizhi”, treated as a variety (A. dahu- rica var. formosana).      The results of karyotype analysis are shown in Plate 1, 2, with the formula 2n=22 =12 m+2 mSAT+4sm+4st. The karyotypes described here are constantly characterized by satellites attached to the fourth pair of metacentric chromosomes and differ from the pu- blished reports on the other species of the genus.  It is reasonable to say that the five materials collectively named “Baizhi” are taxonomically closely related to each other and could be regarded as conspecific.  Since the second chromosome pair is submetacen- tric in “Dongbeidahuo”, it may be justifiable to separate the wild plant from the cul- tivated ones and treat them as two separate varieties.     

Exploring high school students' and teachers' preferences toward the constructivist Internet‐based learning environments in Taiwan

This paper explores high school students' and teachers' preferences towards constructivist Internet‐based learning environments. The study proposes a framework, including two dimensions and five aspects, to illustrate the features of the Internet‐based learning environments. Based upon this framework, the Constructivist Internet‐based learning environment survey improvement (CILESI) was developed, which includes the scales of ease of use, multiple sources, student negotiation, reflective thinking, critical judgement and epistemological awareness. Questionnaire responses gathered from 630 high school students in Taiwan suggested that the CILESI showed adequate reliability in assessing students' preferences. Male students placed more emphasis on the student negotiation, critical judgement and epistemological awareness enhanced by the Internet‐based learning environments than female students did. In addition, the teachers of the sampled students (n?=?78) were also surveyed by CILESI. The teachers tended to express stronger preferences on the ease of use of the Internet‐based learning environments than did their students. However, students, when compared with their teachers, seemed to express more preferences towards the features of student negotiation, reflective thinking, critical judgement and epistemological awareness of Internet‐based learning environments.     

伞形科植物染色体数目报告

本文报道了伞形科15属24种和交种的染色体数，其中18个种和变种是首次报道。研     究表明， 我国天胡荽属 (Hydrocotyle L．)是伞形科多倍体比较普遍的类群。柴胡属(Bupleu-     rum L.)分别有4、6、7、8等基数，茴芹属(Pimpinella L.)的毛果组(Sect. Tragium)和光     果组(Sect．Tragoselinum)的代表种类的基数分别为9和10，因此，染色体基数可作为深入     研究某些属内种类演化的细胞学资料之一。思茅独活(Heracleum henryi Wolff)的花粉母细    胞在终变期时出现了4体环，说明结构杂合体可能是伞形科种类分化的一个因素。     

The Project on Innovative Teaching Methods — An Overview

Over the past several years, the education system in Singapore has undergone very significant and far-reaching changes, especially in terms of the programmes and resources available to teachers and pupils. New textbooks and teaching materials have been introduced into the schools by the Curriculum Development Institute of Singapore (CDIS). Within the Institute of Education (IE), teacher education programmes for pre-service trainees and in-service teachers have also undergone review and change to meet new needs and expectations.     

Simplification and improvement of prediction model for elastic modulus of particulate reinforced metal matrix composite

1 Introduction a Elastic modulus is an important index to reflect the resistance of a composite against deformation under an applied force. Elastic modulus measurement of a composite is restricted by some factors, for instance, test samples need to confor…     

Courseware development with animated pedagogical agents in learning system to improve learning motivation

The addition of animated pedagogical agents (APAs) in computer-assisted learning (CAL) systems could successfully enhance students' learning motivation and engagement in learning activities. Conventionally, the APA incorporated multimedia materials are constructed through the cooperation of teachers and software programmers. However, the thinking and technical gap between two roles, a concept/content provider (teacher) and an implementer (software programmer), may lead to the concept distortion and loss in the final teaching material implementations. This often results in preventing a teacher from preparing his or her own APA-based multimedia learning systems. This study aims to develop a courseware to facilitate the CAL through the combination of the two roles into a single one and then teachers can use it freely by themselves. The courseware can help teachers to develop appropriate multimedia instructional materials incorporating APAs, which attracts students' attention and enhances their interest in learning. Furthermore, in this study two separate trial experiments were conducted to measure the teachers' satisfaction with the courseware and students' learning motivation after using APA-based multimedia learning systems. The results show that the participating teachers were satisfied with the courseware and would like to apply it in their instruction. Moreover, the participating students were strongly motivated by the customized APA-based multimedia learning systems. Therefore, the proposed courseware could give teachers a good opportunity to add pedagogical value to the curriculum, so that students' learning interest and motivation could be enhanced.     

Creating a Business Strategy Evaluation Model for National Museums Based on the Views of Curators

The aim of this study is to find the critical factors that influence Taiwan's national museum business performance based on its curators’ views. The study explored the causal relationships among the criteria that emerged in the study and of each sub‐criteria. Since developing a business strategy is a multiple‐criteria decision‐making (MCDM) problem, this study adopted the causal‐effect model of decision‐making trial and evaluation laboratory (DEMATEL) technique. The DEMATEL technique simplifies and visualizes the interrelationships among decision‐making criteria. The study identified four core criteria – benefits, opportunity, costs, and risks, as key influencers in the national museum business performance. Each key criteria was supported by a set of sub‐criteria which, when considered together, produced an influential network relations map. The results of this study provided Taiwan's national museum curators with an idea‐based understanding of how to create business and marketing strategies that could enhance exhibition features, experience activities, and facilities that could be linked to satisfaction of visitors’ desires and offer a potentials strategy for assessing likelihood of return visits.     

Dynamic processes of conceptual change: Analysis of constructing mental models of chemical equilibrium

The purpose of this study was to investigate students' mental models of chemical equilibrium using dynamic science assessments. Research in chemical education has shown that students at various levels have misconceptions about chemical equilibrium. According to Chi's theory of conceptual change, the concept of chemical equilibrium has constraint‐based features (e.g., random, simultaneous, uniform activities) that might prevent students from deeply understanding the nature of the concept of chemical equilibrium. In this study, we examined how students learned and constructed their mental models of chemical equilibrium in a cognitive apprenticeship context. Thirty 10th‐grade students participated in the study: 10 in a control group and 20 in a treatment group. Both groups were presented with a series of hands‐on chemical experiments. The students in the treatment group were instructed based on the main features of cognitive apprenticeship (CA), such as coaching, modeling, scaffolding, articulation, reflection, and exploration. However, the students in the control group (non‐CA group) learned from the tutor without explicit CA support. The results revealed that the CA group significantly outperformed the non‐CA group. The students in the CA group were capable of constructing the mental models of chemical equilibrium—including dynamic, random activities of molecules and interactions between molecules in the microworld—whereas the students in the non‐CA group failed to construct similar correct mental models of chemical equilibrium. The study focuses on the process of constructing mental models, on dynamic changes, and on the actions of students (such as self‐monitoring/self‐correction) who are learning the concept of chemical equilibrium. Also, we discuss the implications for science education. © 2002 Wiley Periodicals, Inc. J Res Sci Teach 39: 688–712, 2002     

Terminus Amnesia: Cherokee Freedmen,Citizenship, and Education

In 2007, the Cherokee Nation of Oklahoma amended its constitution to limit membership to only those who can trace lineal descent to an individual listed as Cherokee by Blood on the final Dawes Rolls. This exercise of sovereignty paradoxically ties the Dawes Rolls, the colonial instruments used to divide the lands and peoples of the Cherokee Nation, and self-determination. In the process, it effectively disenrolls Cherokee Freedmen, the descendants of Blacks enslaved by the Cherokee Nation. In this article, we explore the implications of this history in the context of self-determination and sovereignty, particularly looking at the influence of colorism on the Dawes Rolls and its ongoing effects. Our goal is to share a piece of history that is often obscured or unknown; to explore how and to what extent the exercise of self-determination and sovereignty in Indigenous nations is impacted by colorism; and finally to consider implications for practice created by the disenfranchisement of peoples from Indigenous nations.