The effects of the use of a conversational model and opportunities for reflections in computer-based role playing

This study examined the effects of an instructional program on 21-year-old students' interpersonal skills development (N = 104). The HyperCard 2.1 program ¿Telling bad news¿ could contain a conversational model that informed students about the main moments and actions in conducting a bad-news conversation. In addition, the program could vary the students' opportunities for reflection by slowing down the dialog. It was expected that the conversational-model-present groups and the high reflection groups would show more effective interpersonal skill acquisition, knowledge acquisition, and a more complete understanding of the skill (better tests results) than the conversational-model-absent groups and the low reflection groups. Both elements were found to affect the students' interpersonal skill development. The presence of a conversational model significantly improved the students' role-play, F(1, 94) = 8.79, p < .01, and their performance on the knowledge test, F(1, 94) = 115.28, p < .001. When also given opportunities for reflection, the students' performance in a roleplay and on the knowledge test improved even more, F(4, 91) = 2.69, p < .05. The instruction program with the presence of a conversational model in combination with opportunities for reflection is, therefore, considered as having the potential to assist in realizing effective gradual lead into interpersonal skills learning and instruction for novices

Non-perturbative determination of anisotropy coefficients in lattice gauge theories

We propose a new non-perturbative method to compute derivatives of gauge coupling constants with respect to anisotropic lattice spacings (anisotropy coefficients), which are required in an evaluation of thermodynamic quantities from numerical simulations on the lattice. Our method is based on a precise measurement of the finite temperature deconfining transition curve in the lattice coupling parameter space extended to anisotropic lattices by applying the spectral density method. We test the method for the cases of SU(2) and SU(3) gauge theories at the deconfining transition point on lattices with the lattice size in the time direction $N_t=4$ -- 6. In both cases, there is a clear discrepancy between our results and perturbative values. A longstanding problem, when one uses the perturbative anisotropy coefficients, is a non-vanishing pressure gap at the deconfining transition point in the SU(3) gauge theory. Using our non-perturbative anisotropy coefficients, we find that this problem is completely resolved: we obtain $\Delta p/T^4 = 0.001(15)$ and $-0.003(17)$ on $N_t=4$ and 6 lattices, respectively.Comment: 24pages,7figures,5table

Critical behaviour and scaling functions of the three-dimensional O(6) model

We numerically investigate the three-dimensional O(6) model on 12^3 to 120^3 lattices within the critical region at zero magnetic field, as well as at finite magnetic field on the critical isotherm and for several fixed couplings in the broken and the symmetric phase. We obtain from the Binder cumulant at vanishing magnetic field the critical coupling J_c=1.42865(3). The universal value of the Binder cumulant at this point is g_r(J_c)=-1.94456(10). At the critical coupling, the critical exponents \gamma=1.604(6), \beta=0.425(2) and \nu=0.818(5) are determined from a finite-size-scaling analysis. Furthermore, we verify predicted effects induced by massless Goldstone modes in the broken phase. The results are well described by the perturbative form of the model's equation of state. Our O(6)-result is compared to the corresponding Ising, O(2) and O(4) scaling functions. Finally, we study the finite-size-scaling behaviour of the magnetisation on the pseudocritical line.Comment: 13 pages, 20 figures, REVTEX, fixed an error in the determination of R_\chi and changed the corresponding line in figure 13

Lithographic band gap tuning in photonic band gap crystals

We describe the lithographic control over the spectral response of three-dimensional photonic crystals. By precise microfabrication of the geometry using a reproducible and reliable procedure consisting of electron beam lithography followed by dry etching, we have shifted the conduction band of crystals within the near-infrared. Such microfabrication has enabled us to reproducibly define photonic crystals with lattice parameters ranging from 650 to 730 nm. In GaAs semiconductor wafers, these can serve as high-reflectivity (> 95%) mirrors. Here, we show the procedure used to generate these photonic crystals and describe the geometry dependence of their spectral response

Time Course of the Increase in the Myocardial Slow Inward Current after a Photochemically Generated Concentration Jump of Intracellular cAMP

Voltage-clamped atrial trabeculae from bullfrog hearts were exposed to membrane-permeant photolyzable o-nitrobenzyl esters of cAMP and cGMP. UV flashes produced intracellular concentration jumps of cAMP or cGMP. With the cAMP derivative, flashes resulted in an increased slow inward current (Isi), producing a broadened action potential. The Isi reached a maximum 10-30 sec after the flash and decreased over the next 60-300 sec. The first increases were observable within 150 msec; this value is an upper limit imposed by the instrumentation. Responses to flashes lasted longer at higher drug concentrations and in the presence of the phosphodiesterase inhibitor papaverine; effects of flashes developed and decreased faster at higher temperature. Although the amplitude of the Isi was increased, its waveform and voltage sensitivity were not affected. Intracellular concentration jumps of cAMP failed to affect the muscarinic K+ conductance. There were no observable effects of cGMP concentration jumps. The data confirm (i) that cAMP regulates the Isi and (ii) that the 5- to 10-sec delay between application of ß-agonists and the onset of positive inotropic effects, observed in previous studies, has been correctly ascribed to events prior to the interaction between cAMP and protein kinase

OH 12.8-0.9: A New Water-Fountain Source

We present observational evidence that the OH/IR star OH 12.8-0.9 is the fourth in a class of objects previously dubbed "water-fountain" sources. Using the Very Long Baseline Array, we produced the first images of the water maser emission associated with OH 12.8-0.9. We find that the masers are located in two compact regions with an angular separation of ~109 mas on the sky. The axis of separation between the two maser regions is at a position angle of 1.5 deg. East of North with the blue-shifted (-80.5 to -85.5 km/s) masers located to the North and the red-shifted (-32.0 to -35.5 km/s) masers to the South. In addition, we find that the blue- and red-shifted masers are distributed along arc-like structures ~10-12 mas across oriented roughly perpendicular to the separation axis. The morphology exhibited by the water masers is suggestive of an axisymmetric wind with the masers tracing bow shocks formed as the wind impacts the ambient medium. This bipolar jet-like structure is typical of the three other confirmed water-fountain sources. When combined with the previously observed spectral characteristics of OH 12.8-0.9, the observed spatio-kinematic structure of the water masers provides strong evidence that OH 12.8-0.9 is indeed a member of the water-fountain class.Comment: 12 pages, 2 figures (1 color), accepted for publication in the Ap J Letter