Vicente Gonξcalves 不等式的一个注记

In this paper,a new proof of the inequality of Vicente Goncalves was given.The method may be powerful to deal with some problems of polynomials.As an application,a new inequality for the coefficients of a polynomial and its roots was derived.     

Using Research Based Assessment Tools in Professional Development in Current Electricity

We present a practical way of adapting and using four research-based assessments for different purposes in an electricity and magnetism course for K-8 science teachers. The course is designed to accomplish conceptual change toward accepted scientific conceptions as well as introducing teachers to materials and activities appropriate for their classrooms. Our data support that using the research-based tests to identify alternative conceptions and discuss test results with teachers is a promising way to use the knowledge of alternative conceptions in professional development. We also identify some mismatches between the research of conceptual change and its use in programs of professional development.

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Strategies for incorporating cultural competence into childbirth education curriculum

Cultural competence affects all interactions with prospective parents and families. Childbirth educators need to assess their own cultural competence, beginning with an understanding of their own background and how it affects interactions with families. The purpose of this article is to enhance the incorporation of cultural competency, cultural awareness, and cultural sensitivity into the childbirth education curricula. Methods for enhancing cultural competence in a multicultural global society are discussed. Strategies are also presented to address the challenges of assessing parents and families of diverse cultures and their beliefs, traditions, and special needs in the plan of care.     

Providing Bottom-Up Support to Middle School Science Teachers’ Reform Efforts in Using Inquiry-Based Kits

Middle grades science teachers need professional support in practice as they implement new inquiry-based science. Professional development schools can provide this bottom-up support through connecting preservice and inservice teacher education programs in classroom practice. In this study, coteaching arrangements with secondary science education majors provided additional teachers in the classroom to support a materials-rich curriculum and the needed associated pedagogies. Science education majors provided needed assistance in troubleshooting difficulties with the new curriculum. They also provided needed content knowledge to support inquiry, along with creating moments and space for teachers to reflect on inquiry practice. Ongoing assistance by preservice teachers allowed inservice teachers to progress from logistical concerns in implementing kit curriculum to concerns regarding student learning and the supporting professional development.

Analytic Frameworks for Assessing Dialogic Argumentation in Online Learning Environments

Over the last decade, researchers have developed sophisticated online learning environments to support students engaging in dialogic argumentation. This review examines five categories of analytic frameworks for measuring participant interactions within these environments focusing on (1) formal argumentation structure, (2) conceptual quality, (3) nature and function of contributions within the dialogue, (4) epistemic nature of reasoning, and (5) argumentation sequences and interaction patterns. Ultimately, the review underscores the diversity of theoretical perspectives represented within this research, the nature of dialogic interaction within these environments, the importance of clearly specifying theoretical and environmental commitments throughout the process of developing or adopting an analytic framework, and the role of analytic frameworks in the future development of online learning environments for argumentation.

Temporal integration in Pavlovian appetitive conditioning in rats

We used an appetitive sensory preconditioning procedure to investigate temporal integration in rats in two experiments. In Phase 1, rats were presented with simultaneous compound trials on which a 10-sec conditioned stimulus (CS) X was embedded within a 60-sec CS A. In Group Early, CS X occurred during the early portion of CS A, whereas in Group Late, CS X occurred during the latter portion of CS A. In Phase 2, CS X was paired simultaneously with sucrose. On a subsequent test with CS A, the rate of magazine entries peaked during the early portions of the stimulus in Group Early and during the latter portions of the stimulus in Group Late (Experiments 1 and 2). Similar response peaks were not observed on tests with a control stimulus that had been presented in compound with a stimulus that did not signal reward (Experiment 2).     

Flavor-evaluative conditioning is unaffected by contingency knowledge during training with color-flavor compounds

In two experiments, participants inspected and drank a series of drinks, half of which contained sugar and half unpalatable Tween20 (tween). Each sugar and tween drink had a particular flavor and color. Following this training, the flavors of the sugar drinks were assigned higher hedonic evaluations than were those of the tween drinks, even though the participants did not reliably report which flavors had been present in the sugar and tween drinks during training. Moreover, the evaluative conditioning of the flavors was unaffected by whether or not the colors alone had been pretrained to predict the presence of sugar or tween in the drinks. In accord with Baeyens, Eelen, van den Bergh, and Crombez (1990), we conclude that flavor-evaluative conditioning is not mediated by contingency learning.     

Maintenance of responding when reinforcement becomes delayed

In four experiments with rats, we examined the persistence of behavior when reinforcement was switched from immediate to delayed. In Experiment 1, lever pressing elicited by instrumental training with immediate reinforcement continued when a 20-sec delay of reinforcement was introduced (easy-to-hard condition), whereas when the delay condition was introduced from the start (hard-to-hard condition), responding remained low throughout. A similar result was obtained in Experiment 2, in which lever pressing was elicited by a classical conditioning (autoshaping) procedure. In Experiment 3, rats initially trained with delayed reinforcement continued to respond at a low rate when switched to immediate reinforcement (hard-to-easy condition). By measuring magazine entry (goal tracking) as well as lever pressing (sign tracking) in Experiment 4, we confirmed that such transfer effects at least partly involve the persistence of whatever type of behavior was initially dominant.     

Explanations of attitudes to change: Colombian mathematics teachers’ conceptions of the crucial determinants of their teaching practices of beginning algebra

This article arises from a study whose overall purpose was to investigate the relationship between Colombian mathematics teachers’ conceptions of beginning algebra and their conceptions of their own teaching practices. The teachers’ understandings of their teaching practices were explored with a view to unravelling their conceptions of change in their teaching. Focusing on the perspectives of teachers afforded opportunities that exposed the powerful role that the teachers’ conceptions of social/institutional factors of teaching played in their conceptions of their practices. The degree to which the teachers attributed these (external) factors as crucial reasons for what they do in their teaching was the basis of a categorisation of their conceptions of the crucial determinants of their teaching practices into three types. The findings are particularly relevant to our understanding of the stability of mathematics teaching approaches in the Colombian context but have likely implications for a range of international education contexts. Specific implications for the development of the research into teachers’ conceptions of mathematics and its teaching, and for teacher education programmes are presented.

Listening and reflecting: an introduction to the special issue

The topic of listening has been broadly neglected in educational studies. This special issue presents studies on the connections between listening and reflecting in educational contexts.