Based on quantum hydrodynamics theory (QHD), the propagation of nonlinear quantum dust-ion acoustic (QDIA) solitary waves in a ‎collision-less, unmagnetized four component quantum plasma consisting of electrons, positrons, ions and stationary negatively charged ‎dust grains with dust charge variation is investigated using reductive perturbation method. The charging current to the dust grains ca...

background: learning of clinical skills in the intensive care unit (icu) is important for nursing students. “direct observation of procedural skills (dops)” is a modified objective method in the field of medical sciences, and we conducted this study with the aim of investigating the effect of evaluation using dops method on learning practical skills among nursing students in the icu. materials ...

This study explored various methods of combining observational learning via demonstration with the effects of overt practice for learning a discrete action pattern. Three groups were compared that varied by the timing of demonstration in relation to practice. An all-pre-practice demonstration group viewed 10 pre-practice videotape demonstrations of an expert performing the skill, and then engag...

Participants learned different keystroke patterns, each requiring that a key sequence be struck in a prescribed time. Trials of a given pattern were either blocked or interleaved randomly with trials on the other patterns and before each trial modeled timing information was presented that either matched or mismatched the movement to be executed next. In acquisition, blocked practice and matchin...