Overshadowing of explicitly unpaired conditioned inhibition is disrupted by preexposure to the overshadowed inhibitor

In two conditioned lick-suppression experiments with rats, the interaction of preexposure to a target stimulus and subsequent overshadowing of conditioned inhibition treatment was examined. Blaisdell, Bristol, Gunther, and Miller (1998) have demonstrated that stimulus preexposure and overshadowing counteract each other in their effects on Pavlovian excitation, producing strong excitatory responding to the target stimulus. In the present experiments, a conditioned inhibition analogue of this effect was examined. Overshadowing of conditioned inhibition (i.e., attenuation of inhibitory control of behavior by the target stimulus) was demonstrated when a more salient stimulus was compounded with the target inhibitor during conditioned inhibition training. However, the overshadowing deficit was attenuated by preexposing the target stimulus prior to overshadowing treatment. To account for this phenomenon, we contrast the comparator hypothesis (Miller & Matzel, 1988) with contemporary models that focus on associative acquisition.     

Teaching Probability for Conceptual Change La Enseñanza De La Probabilidad Por Cambio Conceptual

This work presents a theoretical proposal for a methodology for the teaching of probability theory. The theoretical proposal has a dual inspiration: (1) the epistemological approach of Lakatos (1978b) regarding the quasi-empirical nature of mathematical theories; (2) the perspective of conceptual change for the teaching-learning process, as formulated by Strike and Posner (1992). The scientific content taught and the didactic methods used in the classroom should, according to this proposal, respect and conform to this dual inspiration. We also present an evaluation of the methodology in a real context: six Spanish high school classes of students aged 14–15. The main purpose of the research was to answer this question: Is our didactic proposal more effective than traditional methodology? We operatively identify the concept of traditional teaching, and establish several indicators of effectiveness: the mastery of elementary probability calculations, the quality of intuitive reasoning in probability, and the conceptual and attitudinal change produced. We found significant differences on all indicators, except for attitudinal change, in favour of the group that followed our proposal.     

Strides Toward Equity in an Urban Center: Temple University's Professional Development Schools Partnership

Many educators believe that the goal of equity is far from being achieved given the dilemmas faced by today's inner city public schools. The authors examine the potential of Temple University's Professional Development School Partnership, a collaborative project with the School District of Philadelphia, to facilitate educational equity within an urban center. Current understandings of the construct of equity are identified and used to explore the possibilities and challenges of striving for equity in the urban center. The development of this partnership documents growth into a more inclusive, expansive, and collaborative style of working together. A closer look into this process is provided by an in-depth discussion of two essential components of the partnership, namely, its culturally responsive process and its objective of transforming the teaching and learning conditions of schools. It is argued that school systems need to look critically at their own educational resources as well as policies and practices to guarantee that they genuinely promote participation and achievement of all students. In essence we contend that there cannot be equity without the assurance that students will achieve to their fullest potential.     

History and Philosophy of Science through Models: The Case of Chemical Kinetics

The case for a greater role for the history and philosophy of science in science education is reviewed. It is argued that such a role can only be realised if it is based on both a credible analytical approach to the history and philosophy of science and if the evolution of a sufficient number of major themes in science is known in suitable detail. Adopting Lakatos' Theory of Scientific Research Programmes as the analytical approach, it is proposed that the development, use, and replacement, of specific models forms the core of such programmes.Chemical kinetics was selected as an exemplar major topic in chemistry. Eight models which have played a central role in the evolution of the study of chemical kinetics were identified by an analysis of the literature. The implications that these models have for the teaching and learning of chemistry today are discussed.     

Young Children Are Wishful Thinkers: The Development of Wishful Thinking in 3- to 10-Year-Old Children

Previously, research on wishful thinking has found that desires bias older children’s and adults’ predictions during probabilistic reasoning tasks. In this article, we explore wishful thinking in children aged 3- to 10-years-old. Do young children learn to be wishful thinkers? Or do they begin with a wishful thinking bias that is gradually overturned during development? Across five experiments, we compare low- and middle-income United States and Peruvian 3- to 10-year-old children (N = 682). Children were asked to make predictions during games of chance. Across experiments, preschool-aged children from all backgrounds consistently displayed a strong wishful thinking bias. However, the bias declined with age.     

Learning from Friends and Terminating Friendships: Retrieving Friendship as a Moral Educational Concept

In contrast to ancient times, friendship is rarely discussed nowadays as a resource in moral education. Even within Aristotle-inspired character education, where it could naturally claim pride of place, its coverage is miniscule compared, say, to that of the emulation of moral exemplars. The aim of the present article is to retrieve friendship as a moral educational concept: to explain how moral educational goals define and sustain deep friendships, and how the thorny issue of when friendships should be terminated is best understood in terms of considerations as to whether they have exhausted their educational potential. By arguing that education is the raison d'être of deep friendship, Kristján Kristjánsson shows how friendship is developmentally constituted and, in its most complete form as “character friendship,” educationally executed. There is no such thing as friendship per se, but rather friendship at a certain developmental niveau (or level), with its specific developmental assets and liabilities: qualitatively differentiated according to its educational affordances. While operating within a broad Aristotelian framework, Kristjánsson devotes two sections to charting the moral educational liabilities that may dissipate even the most complete friendships, a topic mostly overlooked by Aristotle himself.     

Evidence and its consequences in educational research

We begin by arguing that the continuing dominance of ‘evidence-based’ thinking in educational policymaking does serious harm to the notion of evidence itself; also that it brings a loss of coherence to education as a practice that might wish to be regarded as a coherent and research-informed one. The second section of the article suggests that the invidious consequences of ‘evidence-based’ thinking are likely to continue unless energetically challenged by a vibrant and robust understanding of education as a practice in its own right. In elucidating such an understanding, we investigate closely the notions of practice and practitioner, and their intrinsic connections, drawing on landmark researches on practice by authors like Alasdair MacIntyre and Joseph Dunne. Building on the understanding of education as a practice in its own right, the third section argues that the Dewey-inspired notion of justified warrant, rather than proof or replicability, is more appropriate to research claims made in education. Here we focus in particular on action research, which has experienced recurring difficulties in having its research credentials recognised.     

Optimal pricing and grant policies for museums

The “free access” policy designed by the British Government has encouraged interest in museum financial issues. We define a principal-agent model for museum administration where there are two income sources: public grants and ticket revenues. This model allows us to define the optimal contract determining public grants, ticket prices, budget and managerial effort. We find a theoretical explanation for the inelastic pricing strategy commonly adopted in cultural economics. We further find that museum manager should never have any control over the price of tickets. The model can also be applied to other institutions, such as schools or NGOs, which are able to raise funds directly from private (e.g., ticket revenues or membership fees) or public sources. JEL Classification number H20, H42, C70, D80, Z10     

Interaction between cells in dielectrophoresis and electrorotation experiments

Progress in microelectrode-based technologies has facilitated the development of sophisticated methods for manipulating and separating cells, bacteria, and other bioparticles. For many of these various applications, the theoretical modeling of the electrical response of compartmentalized particles to an external field is important. In this paper we address the analysis of the interaction between cells immersed in rf fields. We use an integral formulation of the problem derived from a consideration of the charge densities induced at the interfaces of the particle compartments. The numerical solution by a boundary element technique allows characterization of their dielectric properties. Experimental validation of this theoretical model is obtained by investigating two effects: (1) The influence that dipolar “pearl chaining” has on the dielectrophoretic behavior of human T lymphocytes and (2) the frequency variation of the spin and orbital torques of approaching insulinoma β-cells in a rotating field.