Measuring One Aspect of Teachers’ Affective States: Development of the Science Teachers’ Pedagogical Discontentment Scale

The aim of this research is to describe the development of the Science Teachers’ Pedagogical Discontentment Scale, an instrument that measures the discontentment that arises in teachers as they recognize a mismatch between their own pedagogical beliefs and goals and their actual classroom practices. From a conceptual change perspective, we explore the meaning of pedagogical discontentment and discuss its role in shaping teachers’ receptivity to messages of reform. We present an instrument that can be used to measure teachers’ pedagogical discontentment, an instrument that will allow science educators to better describe the affective states of teachers as they enter professional development experiences. The items for the initial instrument were derived from a series of interviews with practicing teachers; from these interviews, a group of 42 items were designed around a group of five subscales. The final instrument, revised after two rounds of field testing, includes 21 multiple‐choice items clustered around six subscales (subscales derived from interviews with science teachers). The processes used to develop the items and to refine instrument are discussed. Uses for this instrument to inform professional development experiences are explored as well as implications.     

一般n阶特征量泛函的Euler-Lagrange方程及与定量因果原理、相对性原理和广义牛顿三定律的统一

本文获得了有各种相互作用的一般n阶特征量泛函,其耦合系数反映了不同特征量泛函之间的耦合强度.依据定量因果原理,导出了一般n阶特征量泛函的变分原理,获得了一般n阶特征量泛函的Euler-Lagrange方程,它的不同系数可拟合不同的物理现实,如从线性到任意n阶非线性物理系统,使复杂难解的任意n阶非线性物理系统变得具体可解.并获得了该对称变换下不变的m个的守恒量,以及它们之间的关系和统一描述.依据定量因果原理导出了相对性原理,证明了绝对加速参考系、牵连参考系和相对参考系的力都有来自加速度和质量变化的贡献.利用定量因果原理自然导出了广义牛顿第一定律和广义牛顿第二定律,而且还导出了一个新定律,即广义牛顿第三定律,亦即平移不变性系统合力为零定理.进而将研究结论应用于对银河系的修正引力势、分子势、夸克禁闭势等,且其结果与物理实验一致.     

A generalized phase space for classical fermions arising out of Schönberg's geometric albegras

An algebraic structure is developed which can be used as a phase space for classical fermions. This structure incorporates superanalysis, a Hamiltonian type spin dynamics, and certain geometric algebras of Schönberg.     

Problem Solving: Teachers' Perceptions,Content Area Models,and Interdisciplinary Connections

Features of common problem-solving models in mathematics and science, as well as those found in business and industry today, are discussed. Commonalties in the models are used to advance a case for interdisciplinary or integrated instruction in mathematics, science and technology. The Integrated Mathematics, Science and Technology (IMaST) program's problem-solving model is presented as an example of a curriculum project that draws upon the commonalties in the problem-solving models as a basis for a seventh grade integrated curriculum.     

Asymptotic freedom,infrared convergence and supersymmetry

The conditions for infrared convergence and asymptotic freedom are investigated for a system in which (in order to produce a spontaneous breakdown) a supersymmetric matter-matter interaction is added to the supersymmetric Yang-Mills Lagrangian. It is found that, in contrast to conventional theory, the conditions imposed by the asymptotic freedom of the matter-matter interaction are not stringent, and are automatically satisfied for adjoint representations. The conditions for infrared convergence are also not too stringent. However the joint conditions for asymptotic freedom and infrared convergence turn out to be quite stringent. Nevertheless, a model is proposed which, subject to some reservations, appears to satisfy the joint conditions.     

Towards the rational design of MRI contrast agents: electron spin relaxation is largely unaffected by the coordination geometry of gadolinium(III)-DOTA-type complexes

Electron-spin relaxation is one of the determining factors in the efficacy of MRI contrast agents. Of all the parameters involved in determining relaxivity it remains the least well understood, particularly as it relates to the structure of the complex. One of the reasons for the poor understanding of electron-spin relaxation is that it is closely related to the ligand-field parameters of the Gd(3+) ion that forms the basis of MRI contrast agents and these complexes generally exhibit a structural isomerism that inherently complicates the study of electron spin relaxation. We have recently shown that two DOTA-type ligands could be synthesised that, when coordinated to Gd(3+), would adopt well defined coordination geometries and are not subject to the problems of intramolecular motion of other complexes. The EPR properties of these two chelates were studied and the results examined with theory to probe their electron-spin relaxation properties.     

Synthesis and relaxometric studies of a dendrimer-based pH-responsive MRI contrast agent

The design of effective pH responsive MRI contrast agents is a key goal in the development of new diagnostic methods for conditions such as kidney disease and cancer. A key factor determining the effectiveness of an agent is the difference between the relaxivity of the "on" state compared to that of the "off" state. In this paper, we demonstrate that it is possible to improve the pH-responsive action of a low molecular weight agent by conjugating it to a macromolecular construct. The synthesis of a bifunctional pH responsive agent is reported. As part of that synthetic pathway we examine the Ing-Manske reaction, identifying an undesirable by-product and establishing effective conditions for promoting a clean and effective reaction. Reaction of the bifunctional pH responsive agent with a G5-PAMAM dendrimer yielded a product with an average of 96 chelates per dendrimer. The relaxivity of the dendrimer conjugate rises from 10.8 mM(-1) s(-1) (pH 9) to 24.0 mM(-1) s(-1) (pH 6) per Gd(3+) ion. This more than doubles the relaxivity pH response, Deltar(1), of our agent from just 51 % for the original low molecular weight chelate to 122 % for the dendrimer.