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The research reported here investigates the efficacy of a module in an Advanced Certificate in Education course in promoting conceptual understanding in Astronomy. The research attempted to find out how teachers' understanding of astronomy concepts and processes change after completing this module as well as the reasons for such changes, if any. The conceptual framework applied in the study is based on three constructs which influence learning. A pre- and post-module questionnaire, as well as interviews were the instruments used to collect data from a cohort of students registered for this module. The data revealed that very little conceptual change occurred. Possible reasons for the lack of conceptual change are: Classroom environments and instructional strategies that are not conducive to conceptual change; an emphasis on declarative knowledge with little attention paid to procedural knowledge and lastly, students own epistemological beliefs of what constitutes science knowledge and learning. (Contains 2 tables.)

Remote and virtual laboratory classes are an increasingly prevalent alternative to traditional hands-on laboratory experiences. One of the key issues with these modes of access is the provision of adequate audiovisual (AV) feedback to the user, which can be a complicated and resource-intensive challenge. This paper reports on a comparison of two studies of remote and virtual access to hardware, one with rich AV feedback and one without. The comparison shows that the learning outcomes of the remote access mode are dependent upon the richness of the feedback; the learning outcomes of the simulated access mode are largely robust to an absence of feedback. The students' preferences are affected by the feedback, with a clear preference for richer feedback. (Contains 4 tables and 14 figures.)

Abstract A simple random survey was conducted in Ireland during 2005 to estimate the ELISA-prevalence of paratuberculosis, commonly called Johne's disease (JD), in the cattle population. Serum samples were collected from all 20,322 females/breeding bulls over 12 months-of-age in 639 herds. All samples were tested using a commercially available absorbed ELISA. The overall prevalence of infected herds, based on the presence of at least one ELISA-positive animal, was 21.4% (95% CI 18.4%-24.9%). Herd prevalence levels amongst dairy herds (mean 31.5%; 95% CI: 24.6%, 39.3%) was higher than among beef herds (mean 17.9%; 95% CI: 14.6%-21.8%). However, the animal level prevalence was similar. The true prevalence among all animals tested, was calculated to be 2.86% (95%CI: 2.76, 2.97) and for animals >= 2 yrs, it was 3.30% (95%CI: 3.17, 3.43). For animals in beef herds, true prevalence was 3.09% (95%CI: 2.93, 3.24), and for those in dairy herds, 2.74% (95%CI: 2.59, 2.90). The majority of herds had only one ELISA-positive infected animal. Only 6.4% (95% CI 4.7%-8.7%) of all herds had more than one ELISA-positive infected animal; 13.3% (CI 8.7%-19.7%) of dairy herds ranging from two to eight ELISA-positive infected animals; and, 3.9% beef herds (CI 2.4%-6.2%) ranging from two to five ELISA-positive infected animals. The true prevalence of herds infected and shedding Mycobacterium avium subspecies paratuberculosis is estimated to be 9.5% for all herd types; 20.6% for dairy herds; and 7.6% for beef herds. If ELISA positive animals

Abstract Cows are the main economic production units of Ireland's cattle industry. Therefore, demographic information, including overall numbers and survival rates, are relevant to the Irish agricultural industry. However, few data are available on the demographics of cows within a national population, either in Ireland or elsewhere, despite the recent development of comprehensive national cattle databases in many EU Member States. This study has sought: to determine the rate of cow culling from the national herd; to determine the rate of culling by type (dairy, beef), age, method of exit, date of exit and interval between last calving and exit; to calculate the national cow on-farm mortality rate; and to compare the Irish rates with published data from other countries. This work was conducted using data recorded in the national Cattle Movement Monitoring System (CMMS). Culling refers to the exit of cows from the national herd, as a result of death but regardless of reason, and cow-culling rate was calculated as the number of cow exits (as defined above) each year divided by the number of calf births in the same year. Culling rate was determined by type (dairy or beef), date of birth, method of exit (slaughter or on-farm death), month of exit and interval between last calving and exit. The average cow-culling rate during 2003 to 2006 was 19.6% (21.3% for dairy, 18% for beef). While comparisons must be treated with caution, it concluded that the overall rates of culling in Ireland fell within published internationally accepted norms. The on-farm mortality rate of 3.2-4.1% was similar to that reported in comparable studies.

In two experiments, rats first received preexposure to a rectangular arena in which the geometrically equivalent corner pairs (G1 and G2) were coincident with different luminance characteristics (C1 and C2, respectively). In Experiment 1, rats were then placed in a uniform gray rectangular arena where food was located in one geometrically equivalent pair of corners (G1), but not another (G2). Finally, rats were tested in a square arena with CI and C2 and preferred to search in C1 rather than C2. In Experiment 2, following preexposure to G1C1 and G2C2, rats received pairings of CI with food and C2 with no food in a square arena. During testing, rats preferred to search in G1 rather than G2 in a gray rectangular arena. These results demonstrate that reciprocal within-compound associations develop between geometric and luminance information and thereby challenge the view that there is a dedicated geometric module that is impenetrable to information that is not geometric. Keywords: geometry, cue interaction, within-compound associations

We examined the involvement of the hippocampus in short-term changes in exploratory behaviour in an open field (Experiment 1) and experimental contexts (Experiment 2). In Experiment 1, rats with excitotoxic lesions of the hippocampus were more likely to revisit recently visited zones within the open field than were control rats. Similarly, in Experiment 2 rats with hippocampal lesions showed greater exploration of a context that they had recently explored than a context that they had less recently explored. This short-term sensitization effect was not evident in control rats. These findings are consistent with the suggestion that the recent presentation of a stimulus has two opposing effects on behaviour, sensitization, and habituation, and that hippocampal lesions disrupt the short-term process responsible for habituation, but not that responsible for sensitization.

The TITAN facility at TRIUMF has recently initiated a program of performing decay spectroscopy measurements in an electron-beam ion-trap (EBIT). The unique environment of the EBIT provides backingfree storage of the radioactive ions, while guiding charged decay particles from the trap centre via the strong magnetic field. This measurement technique is able to provide a significant increase in detection sensitivity for photons which result from radioactive decay. A brief overview of this device is presented, along with methods of improving the signal-to-background ratio for photon detection by reducing Compton scattered events, and eliminating vibrational noise.

Neural manipulations were used to examine the mechanisms that underlie the acquired equivalence and distinctiveness of cues in rats. Control rats and those with excitotoxic lesions of either the hippocampus (HPC) or entorhinal cortex (EC) acquired the following conditional discrimination: In Contexts A and B, Stimulus X [right arrow] food and Stimulus Y [right arrow] no food, and in Contexts C and D, Y [right arrow] food and X[right arrow] no food. Rats then received many food pellets in A but not in C. After this treatment, control rats showed more magazine activity in B than in D--an acquired equivalence-distinctiveness effect. This effect was also evident in HPC rats but not in EC rats. These results indicate that changes in stimulus distinctiveness are dissociable from the process of conditional learning.

One hundred European university students, with different interests and backgrounds, were asked to complete a questionnaire aimed at understanding their general knowledge and personal rapport with space issues and activities. Although the overall interest in space seemed to be relatively satisfactory, the data resulting from the survey--used for statistical purposes only--showed a poor awareness concerning the past, present and future of space programmes and achievements, and more generally of the economic, political and social implications of space. Stimulated and moved by the survey questions, the students interviewed showed their worries about the already developing process of division, control and commercialisation of space, underlining how the concept of education is differentiated from that of information when dealing with these issues. However, at the same time, all their statements seemed to be based on simple assumptions, preconceptions and presumptions. On the basis of the survey results, the final section of the paper reviews and discusses the present situation of space education in Europe, analysing its deficiencies and suggesting modifications, adjustments and a 'step forward' that should be taken into consideration.

The ability of auditory stimuli to modulate rats' tendency to orient to visual targets was assessed. In Experiment 1, trials where an auditory stimulus (A) signaled one visual array (X) were intermixed with unsignaled presentations of a second array (Y). Comparison of the orienting responses (ORs) to X and Y revealed that A produced a transient (unconditioned) and an emerging (conditioned) disruptive influence on the OR to X. In Experiments 2 and 3, trials where A signaled X were intermixed with others where another auditory stimulus (B) signaled Y. Stimulus A's ability to modulate the OR to X was then assessed by presenting A prior to test arrays containing both X and Y. Control rats were more likely to orient to Y than X (Experiments 2 and 3) and rats with excitotoxic lesions of the hippocampus were more likely to orient to X than Y (Experiment 3). These results show that auditory stimuli exert distinct modulatory influences on the OR to visual stimuli with which they are associated.

Rats received exposure to two serial compounds (A-X and B-Y) comprising auditory stimuli (A and B) followed by localized visual stimuli (X and Y). A and B came to elicit responses that reflected the location of X and Y (Experiment 1). The orienting response (OR) elicited by X and Y declined during exposure to the A-X and B-Y compounds and was restored on trials when A preceded Y, and B preceded X (Experiments 2 and 3). These results, observed with use of relatively neutral stimuli, parallel those observed during Pavlovian conditioning and provide support for A. R. Wagner's (1981) account of associative learning.