Differential conditioned suppression in the Konorski-Lawicka paradigm

In conditioned suppression discriminations, the Konorski-Lawicka paradigm involves A+ trials, where conditioned stimulus A is followed by shock, and sh → A? trials, where A is preceded by shock Rats easily mastered this A+/sh → A? discrimination, as indicated by suppression of food-reinforced barpressing on A+ trials and acceleration of barpressing on sh → A? trials. A history of A+ conditioning resulted in nearly perfect discrimination performance on the very first day of A+/sh → A ? training, but a history of sh→ A? conditioning retarded development of the discrimination. The basis for the development of the discrimination was discussed in terms of an inferred stimulus (sh′) arising from the aftereffects of shock.     

Forgetting of a CS attribute in a conditioned suppression paradigm

Although a number of studies have demonstrated nearly complete retention of fear in a conditioned suppression task, they provide little information about the nature of the memory for the CS. The purpose of the present experiment was to investigate the retention of an attribute of a tonal CS that had been paired with shock and was thus capable of eliciting a conditioned emotional response (CER) in rats. The Kamin blocking effect was utilized to detect changes in the memory of CS attributes. Either 1 or 21 days following conditioning to a tone, separate groups of rats received compound conditioning in which either the original or a novel tone was combined with a light. Subsequent measurement of suppression to the added element (light) indicated that only the original CS produced blocking at the short delay, but that both original and novel tones resulted in blocking at the 21-day interval. This increase in the extent of blocking suggests that memory for specific attributes of the CS does diminish as a function of time.     

Effects of the correlation between a positive and negative US on conditioned suppression in rats

For three groups of rats, an auditory CS, presented while the animals were responding on a variable-interval schedule for food reinforcement, was terminated on half of the trials with a noncontingent footshock. For two groups, half of the trials were also followed after 5 sec by the delivery of free food. In the positively correlated condition (PC) the free food was presented on shocked trials and in the negatively correlated condition (NC) on the nonshocked trials, while the remaining group (S) never received free food. In a fourth group the shock was omitted and free food delivered on half of the trials. Although all shocked groups showed a significant suppression, the magnitude was greater for Group PC than for Groups NC and S, which did not differ. Suppression did not result from the pairing of the CS with food alone. These results do not support the counterconditioning hypothesis that the pairing of a normally noxious stimulus with food reduces its aversiveness.     

Saccharin aversions induced by lithium chloride toxicosis in a backward conditioning paradigm

Seven experimental groups of seven rats each were allowed to consume saccharin solution at different times relative to intubation of lithium chloride solution. Six backward conditioning (BWD) groups were intubed 0.5, 1, 2, 3, 4, and 8 h before saccharin consumption, and a forward conditioning (FWD) group was intubed 0.5 h after saccharin consumption. A no-lithium control group of 14 rats received no intubation. Only the 0.5-h FWD and the 0.5-h BWD groups showed an aversion to saccharin relative to the no-lithium controls. The aversion to saccharin in the 0.5-h FWD group was more pronounced than that in the 0.5-h BWD group. This shows that the aversive effects of lithium toxicosis dissipate far sooner than the aversive effects of X-irradiation.     

Potentiation of attentional enhancement in the pigeon produced by a “blocking” stimulus

In Stage 1, four groups of pigeons were given true discrimination (TD) and four groups were given pseudodiscrimination (PD) training along one of two dimensions orthogonal to wavelength. In Stage 2, all groups received single stimulus (SS) training with a wavelength cue compounded with the former S+ for four of the groups (two TD and Two PD) and with a novel stimulus for the other four (two TD and two PD). For all groups, the SS training was followed by a wavelength generalization test in order to assess the control acquired by the (incidental) wavelength cue during Stage 2. The presence of the former S+ should have blocked the acquisition of control by the wavelength cue leading to flat generalization gradients in the appropriate TD groups. To the contrary, however, these groups showed the sharpest wavelength gradients, i.e., rather than blocking, potentiation was found. One possible interpretation is that the superimposition of the previous S+ served as a reminder of previous TD training, thereby enhancing the transfer of an attentive set from Stage 1 to Stage 2. An alternative conditioning interpretation, suggested in a 1975 paper by Mackintosh, can also be extended to encompass these results.     

The motion of a charged particle in a magnetic field produced by a column current

To determine the motion of a charged particle in a magnetic field produced by a current flowing along a long column conductor, the equation of the motion was established on the basis of Lorentz force. Qualitative analysis and quantitative solutions demonstrated that the motion contains nonlinear oscillation. The oscillation can be treated as the perturbation of the helical motion, Which the particle undergoes in a special condition. The general motion is superposition of two helixes, one as an axis spiraled by another. It is proven that the oscillation is stable.     

Proofs produced by secondary school students learning geometry in a dynamic computer environment

As a key objective, secondary school mathematics teachers seek to improve the proof skills of students. In this paper we present an analytic framework to describe and analyze students' answers to proof problems. We employ this framework to investigate ways in which dynamic geometry software can be used to improve students' understanding of the nature of mathematical proof and to improve their proof skills. We present the results of two case studies where secondary school students worked with Cabri-Géeomèetre to solve geometry problems structured in a teaching unit. The teaching unit had theaims of: i) Teaching geometric concepts and properties, and ii) helping students to improve their conception of the nature of mathematical proof and to improve their proof skills. By applying the framework defined here, we analyze students' answers to proof problems, observe the types of justifications produced, and verify the usefulness of learning in dynamicgeometry computer environments to improve students' proof skills.This revised version was published online in September 2005 with corrections to the Cover Date.     

Proofs produced by secondary school students learning geometry in a dynamic computer environment

As a key objective, secondary school mathematics teachers seek to improve the proof skills of students. In this paper we present an analytic framework to describe and analyze students' answers to proof problems. We employ this framework to investigate ways in which dynamic geometry software can be used to improve students' understanding of the nature of mathematical proof and to improve their proof skills. We present the results of two case studies where secondary school students worked with Cabri-Géeomèetre to solve geometry problems structured in a teaching unit. The teaching unit had theaims of: i) Teaching geometric concepts and properties, and ii) helping students to improve their conception of the nature of mathematical proof and to improve their proof skills. By applying the framework defined here, we analyze students' answers to proof problems, observe the types of justifications produced, and verify the usefulness of learning in dynamicgeometry computer environments to improve students' proof skills.     

Interference and facilitation produced by noncontingent reinforcement in the appetitive situation

The results of experiments on learned helplessness in the appetitive situation have varied from facilitation to debilitating effects produced by exposure to uncontrollable food. The conditions under which the interference effect (debilitation) may occur were examined in the first three experiments, employing the triadic design. Sixteen sets of conditions were examined. The results suggested that the effect occurs when (1) subjects are preexposed to the manipulandum to be used in the test stage, by having it present during pretreatment with uncontrollable food, and (2) the manipulandum employed during pretreatment is absent during the test stage. Furthermore, under the reverse conditions (test manipulandum absent during pretreatment, and pretreatment manipulandum present during testing) and partial reinforcement of the response contingent subjects during pretreatment, the test performance of rats exposed to uncontrollability was facilitated. Experiment 4 confirmed the occurrence of the interference effect under the suggested conditions. Apparently inconsistent results of previous studies may be interpreted in the light of these findings.     

"智能+"时代高等教育新范式探究

文章基于范式理论,从工业革命视角研究高等教育范式演进历程,研究发现,到目前为止高等教育范式演进经历了传道、理智训练、专门化、多学科融合四个阶段.高等教育范式的转换受教育价值观、思维、技术、社会环境、制度、市场六个关键因素的影响."智能+"时代,高等教育新范式是在智能技术群、巨变的社会环境、多元心智和谐可持续发展价值观、人工智能思维、创客制度以及创新创业市场六个关键因素的影响下产生的.基于此,文章构建以数据为中心、多元数字在场的数字人交互共生新范式,形成正向循环的三层学习者成长飞轮,使学习者能够实时永续、按需学习.这种交互共生的高等教育新范式对我国高等教育转型升级具有重要的导向意义.     

Educational leadership and change: structural challenges in the implementation of a shifting paradigm

A great deal of research has been conducted regarding leadership and change. The impact of this research has not been limited to academe, but rather, government policy in different jurisdictions has been directly impacted by developments into collegial forms of leadership. While the positive correlation between leadership and change has been widely acknowledged, this article argues that a disconnect has emerged between the theory and practice signifying that the efficacy of change remains hampered by structural constraints and subjective factors that result in unpredicted outcomes. To explore this thesis, the fundamentals of educational leadership theory, our ability (or inability) to manage change and an analysis of the difficulties faced by leaders as they move from theory to praxis are examined.     

Inclusive education in the Czech Republic: A scoping review of a paradigm shift

This scoping review presents the historical, social, and international influences that shaped the gradual move from segregated to inclusive education for all children in the Czech Republic. The introduction of the 2016 amendment to the Education Act marked a decisive paradigm shift in education policy, which formed the legal basis for services and support measures to be made available for all children with special needs in local mainstream schools. We analysed Czech language and English language peer-reviewed specialist literature to see how these changes have been reflected in current education research. The eighteen studies reviewed provide a complex picture of facilitators and barriers at the level of inclusive culture, policy and practice. Even though progress towards inclusive education in the Czech Republic has been notable, there are still systemic and attitudinal barriers to the education of all children.     

Delayed matching in the pigeon: Interference produced by the prior delayed matching trial

Pigeons’ delayed matching performance on Trial n was examined as a function of whether the correct and incorrect comparison stimuli from Trial n?1 were maintained in the same role on Trial n (positive transitions), were reversed in role on Trial n (negative transitions), or were absent on Trial n (neutral transitions). Relative to neutral transitions, positive transitions did not significantly facilitate performance. Negative transitions, however, produced significant proactive interference on Trial n, and the magnitude of proactive interference was greater when the Trial n retention interval was 1 sec than when it was 0 sec. As the intertriai interval increased from 2 to 10 sec, the amount of interference dissipated. The results suggest that a prior delayed matching trial can serve as a significant source of forgetting but not a significant source of facilitation on an immediately following delayed matching trial.     

Conflict in the family: A continuing education course produced by the open university

This course, first presented by the Open University in 1980, is designed for independent study by people who, in the course of their working lives, come into contact with families suffering serious internal conflicts which place any members—adult or child—in danger of physical or emotional abuse in their own home. The course has been developed at a level which should make it a serious contribution to in-service training for a wide variety of professionals and experienced voluntary workers. It is unique in that it not only examines constructive and destructive aspects of conflict but also integrates written material (16 units) with an audiovisual component (8 TV programmes and 7 cassette tapes) on prevention, diagnosis and intervention relating to the whole spectrum of family conflict and violence including child abuse, sexual abuse, adolescent abuse, spouse abuse, abuse of and by the elderly and abuse of parents by their children. This paper provides a brief outline of the course aims, objectives and content together with information on its usage in the UK and the availability of certain components for international usage.     

Participatory principles in human inquiry: ethics and methods in a study of the paradigm shift experience

In this paper, underlying principles for guiding participation in human science research are outlined. These research principles were originally utilized as a guiding framework for the author's phenomenological study of the change to a new world‐view identified as the paradigm shift (Dudley, 1987). Using this study as an example, the paper focuses on the integration of participatory concepts in research. The concept of participation as ethics discussed in this paper includes the following dimensions: integrity congruence among problem, paradigm, and method; process‐orientation a commitment to research as a shared journey of discovery; empathetic relationships an ethic of mutuality; and empowerment in community a view of knowledge as communal achievement. Finally, a participatory ethic is discussed in terms of its congruence with values that are at the heart of the new social science paradigm.     

The effect of affective characterizations on the use of size and colour in drawings produced by children in the absence of a model

Previous studies have revealed that children increase the size of drawings of topics about which they feel positively and use their most preferred colours for colouring in these drawings, and decrease the size of drawings of topics about which they feel negatively and use their least preferred colours for colouring in these drawings. However, these previous findings have been obtained in studies employing drawing tasks where planning and production difficulties have been minimized by asking the children either to copy or to colour in an outline stimulus of a figure provided by the experimenter. The present experiment was designed to examine whether children also alter the use of size and colour in their drawings in response to emotional characterizations when they are not constrained by the presence of a model. In all 253 children aged between four and 11 years were asked to produce drawings of a neutrally, a positively and a negatively characterized topic (either a man, a dog or a tree). It was found that the children consistently increased the size of the positively characterized figures, did not consistently decrease the size of the negatively characterized figures, used their most preferred colours for the positive figures, and used their least preferred colours for the negative figures. These findings are discussed in relation to the operation of an appetitive‐defensive mechanism and pictorial conventions.