Sample duration and type of stimuli in delayed matching-to-sample in rhesus monkeys

Two experiments were performed to determine the effect of sample duration (0.1, 2, and 4 sec), delay interval (.03, 4, 8, 16, and 32 sec), and type of stimulus (color and shape) on the matching performance of rhesus monkeys. In Experiment 1, the 15 possible delay-duration combinations were randomly presented in blocks of 15 trials. In Experiment 2, each duration was held constant and the five delays randomly presented. Then each delay interval was held constant with the three durations randomly varied. Matching performance increased as sample duration increased (ps < .01 and .005), while length of delay did not significantly affect performance. The type of stimuli paired in the matching test significantly affected performance (ps < .05 and .10) with the shape/shape choices leading to the poorest performance. Stimulus discriminability and amount of training with brief sample durations were implicated as significant determinants of matching performance.     

Correlation: From Picture to Formula

Correlation is introduced intuitively early in the school curriculum by considering patterns in scatter diagrams. Later on, various formulae are used for calculating correlation coefficients. This article suggests ways in which the formulae can be related to the scatter diagrams.     

Children born at risk: What's happening in kindergarten?

Many studies examine the development of infants born at risk for medical and developmental problems during the early years of life, but far fewer follow these children into their school years. This project compared high-risk vs. low-risk children in their performance on the WPPSI at pre- and postkindergarten levels. In general, both groups of children demonstrated increases in performance; however, their patterns of performance were different. The high-risk children showed increases predominantly in the Performance areas of the test, whereas the low-risk children demonstrated increases predominantly in the Verbal areas.     

Community Consultation in Developing Museum Projects: A Case Study Using the Repertory Grid Technique

Good community consultation is a powerful tool in developing new museum projects and exhibitions, facilitating a more effective delivery of service to a diverse public. Existing techniques for both user and community consultation are limited with front end evaluation particularly undeveloped in the sector, often providing no meaningful base by which to compare project outcomes. Tension exists between government, which values quantitative data, and researchers who argue qualitative methods are more appropriate for evaluating community projects. This article reports a pilot study using the repertory grid technique to examine a ‘socially excluded’, ethnically diverse local community's perceptions, expectations and previous experiences of similar projects, to provide a benchmark against which to compare outcomes. This research formed part of the front end evaluation for a New Deal for Community's Project run by Sheffield Galleries and Museums Trust. The repertory grid technique was developed in psychological studies as a means of understanding respondents' own world views, and is particularly helpful in working with people with poor language skills. Although this study only used the technique qualitatively, it can be used to combine both quantitative and qualitative data, providing more robust data for evidence-based policy decisions. Using the repertory grid technique, respondents were able to list both perceived and practical barriers to participation in projects. The technique also enabled them to articulate what would motivate them to become involved in future projects. The repertory grid technique has significant potential for use in community consultation and project evaluation as a means of understanding local residents' perceptions and its visual representation means that its findings can be easily understood by participants, policy-makers and practitioners.     

Maximal heart rate declines linearly with age independent of cardiorespiratory fitness levels

There have been many conflicting observations between the linear or curvilinear decline in maximal heart rate (HR_max) with age. The aim of this study was to determine if linear or curvilinear equations would better describe the decline in HR_max with age in individuals of differing cardiorespiratory fitness (CRF) levels. Treadmill cardiopulmonary exercise test (CPX) results from participants (1510 men and 1134 women; 18–76 years) free of overt cardiovascular disease were retrospectively examined using cross-sectional and longitudinal study designs. Participants completing ≥2 CPX with ≥1 year between test dates were included in the longitudinal analysis (325 men and 150 women). Linear and quadratic regressions were applied to age and HR_max for the whole cohort and respective CRF groups (high, moderate, and low, relative to age and gender normative values). To test for differences among linear, quadratic, and polynomial equations, the change in R² (cross-sectional analysis) and Bayesian information criterion (BIC) (longitudinal analysis) from the linear to the more complex models were calculated. The quadratic or polynomial regression in the cross-sectional analysis, marginally improved the variance in HR_max explained by age compared to the linear regression for the whole cohort (0.2%), moderate fit group (0.3%), and low fit group (0.8%). With no improvements in the high fit group. BIC did not improve for any CRF category in the longitudinal analysis. In conclusion, the minimal differences among linear, quadratic, and polynomial equations in the respective CRF groups, emphasizes the use of linear prediction equations to estimate HR_max.     

Business communication as cultural text: Exchange and feedback of promotional video clips

Our research is a response to the need to improve the understanding of the complexity of global professional communication. To investigate the complex cultural interpretations that producers and audiences apply to professional texts, we developed a two-year interactive project. Business students in New Zealand and Israel produced promotional “texts” – video clips to promote a university program – which they exchanged with their counterparts overseas to receive feedback. We adapted models of home-made visual communication and advertising which used the categories of participants, settings, topics, and style, to analyze the eight clips. Emergent findings suggested two more categories – information and language – as important analytical tools. Variables of age, gender, intra- and intercultural differences, and (cultural) context also resulted in student audiences’ multiple interpretations of the texts. The outcomes indicate the need to extend the culture-in-context approach for a “situation focused communication approach,” where the primary focus is a group of producers and their audience as they produce and interpret a professional text. This approach also foregrounds contextual variables and a plural understanding of culture to accommodate the potential for miscommunication of business and professional texts in pluricultural contexts.     

The detonation wave from solid explosives

It has been shown that the detonation wave from a solid explosive changes in velocity after leaving the explosive. In the case of some low-velocity explosives, e.g., about 2400 metres per second, the velocity of the detonation wave increases by approximately 100–200 metres per second. With other high-velocity explosives, 5000–6000 m./sec., the velocity may decrease to around 4400 metres in some cases.Careful measurements have shown that a zone of uniform velocity exists beyond the surface of the explosive, the dimensions of the zone depending on the diameter of the sphere of the explosive or the diameter of the cartridge detonated. In the case of a $\text{1}\text{1}\text{4}$-inch dynamite cartridge, the zone of uniform velocity extended for about ten inches, while, with a sphere of explosive four inches in diameter, the zone extended for about 25 inches.An explanation of the reason for the high velocity of the detonation wave in the gaseous medium is suggested, linking it up with either the velocity of sound at the temperatures prevailing or the kinetic velocity of the gaseous particles themselves, the latter explanation appearing to be more in accordance with the determined facts. Such an explanation implies the assumption of extremely high momentary temperatures at the wave front, in some cases of over 40,000° C. These extremely high temperatures are due partly to the heat of combustion of the explosive ingredients but more to the heating effect resulting from the enormous pressures developed at the moment of explosion, as previously applied by Berthelot and Dixon in the study of gaseous explosions. Adiabatic conditions are assumed in such calculations. With such an explanation, reasonable agreement between theory and fact is obtained for a number of explosives, and the discrepancies that exist are in cases where discrepancies might be expected.