The effects of preexposure to a warning or a safety signal on the acquisition of a two-way avoidance response in rats

Rats that were given nonreinforced preexposure to either a warning signal or a safety signal were significantly retarded in the subsequent learning of a two-way shock-avoidance response compared to rats that were not preexposed. These results are consistent with Mackintosh’s “learned-irrelevance” formulation of latent inhibition. They do not support a prediction derived from an extension of Kalat and Rozin’s “learned-safety” hypothesis. These findings suggest that preexposures in the total absence of aversive events do not endow a stimulus with safety properties.     

The greater fragility of females' versus males' closest same-sex friendships

Sixty females and 60 males between 10 and 15 years of age were interviewed about difficulties in current and past close same-sex friendships. Based on prior studies, it was hypothesized that females' closest same-sex friendships would be more fragile than those of males. Analyses comparing only the closest same-sex friendship of the two sexes demonstrated that females' current friendships were of a shorter duration, that females were more distressed than males when imagining the potential termination of their friendships, that more females' than males' friends already had done something to hurt the friendship, and that females had more former friendships that had ended than males had. Possible reasons are discussed for the greater vulnerability of this type of relationship for females.     

IMPLICATIONS OF PRESTEL AND OTHER TV PRINT SOURCES

Since Prestel and other televised print sources signal a revolution in the presentation of reading material to the public, it is necessary to ensure that the viewers are able to read the material. Are they ready and able to adapt their reading skills to read televised texts? Differences between page print and television print are discussed, with respect to form and style, and recommendations are made about the responsibility of the educational establishment towards the preparation of potential viewers.     

Alfred Wegener—From continental drift to plate tectonics

What is the nature of the force or mechanism that moves massive continents thousands of miles across? What causes violent earthquakes to displace huge landmasses abruptly? How could great mountain ranges like Himalayas and Alps rise to such incredible heights? What makes earth's interior so restless? Answers to some of these questions may lie in understanding the Earth's interior itself.     

Computer Literacy as Ideology

Some of the most prominent policies in schools throughout the industrialized world today relate to the rapid introduction of computers. The most common rationale for introducing educational microcomputing is the concept of ‘computer literacy’. It is a concept, however, which is so poorly defined and delineated, and so unclear as to purpose and procedure, that it may best be investigated as a form of ideology. The justificatory arguments for computers in classrooms are primarily vocational or practical. They are based on assumptions that computers will be pervasive in the workplace of the future, or that they are soon going to be ‘everywhere’. The more purely pedagogical arguments are secondary: that learning about computers is a worthwhile experience in and of itself, and that computers can be useful productivity tools for other academic work. Drawing upon empirical evidence from an evaluation of computer use in two Canadian high schools, this paper shows how a critical treatment of computer literacy as ideology raises important issues about the computerization of education. It suggests that educators should question whether they have simply taken the ideology of computer literacy at face value, and whether this almost universal policy has received the critical attention it deserves.     

Relative effectiveness of reading practice or word-level instruction in supplemental tutoring: how text matters

In this quasi-experimental study, which is part of a series of investigations on supplemental reading tutoring variations, the relative effectiveness of more intense decoding instruction or text reading practice was examined. Fifty-seven first-grade students scoring in the lowest quartile for reading skills received either classroom reading instruction or one of two treatments: tutoring in word study with text reading practice, or word study tutoring alone. Individual instruction was provided by trained paraprofessional tutors. At the end of first grade, treatment students significantly outperformed their nontutored peers on measures of reading accuracy, reading comprehension, reading efficiency, passage reading fluency, and spelling. Differential treatment effects on passage reading fluency are examined, taking into consideration pretest skill levels and text reading practice characteristics.     

Metaphoric competence in children with learning disabilities

Metaphoric competence was examined in two groups of children with learning disabilities and one group of nondisabled peers ranging in age from 9-0 to 11-0 years. There were five girls and seven boys in each group. One group of students with learning disabilities had a history of spoken language impairment and the other group did not. Subjects were administered three verbal metaphor tasks (comprehension, preference, and completion) and a visual metaphor task, the Metaphor Triads Task (MTT). The three verbal metaphor tasks were administered in three contexts: (a) sentence, (b) story, and (c) story plus visual (pictorial) support. The group with a history of language impairment consistently performed more poorly on the metaphor tasks than the group without a history of language impairment, who, in turn, performed more poorly than the nondisabled children on all but the MTT. Context variations had no effect on children's performance. Theoretical and clinical implications will be discussed.     

Application of CAE in Teaching Vibration Engineering

CAE has enabled vibrational problems, which were regarded as intractable 20 years ago, to be solvable by students using computational support. The paper describes a problem set to final year undergraduates which concerns the torsional vibrational response of a three degrees of freedom system which is subjected simultaneously to three different arbitrarily varying torques. The solution involves the use of standard library routines for matrix multiplication and eigensolutions, a Runge-Kutta routine to solve a second order differential equation and general competence in writing software.