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Undergraduate students of fluid mechanics bring a range of preconceptions to the classroom. The sometimes counterintuitive nature of fluid mechanics means that many of these preconceptions are, in fact, misconceptions. Such misconceptions can be hard to address and can persist even among nominally high-performing students. A pedagogical approach (i.e., predict, test, and reflect) is presented. The approach provides an effective structure for addressing and correcting misconceptions through the use of low-cost hands-on activities that students can quickly and easily undertake during regular class time. The activities all have the same structure of describing the activity, having students make a prediction based on their intuition/prior experience, testing that prediction using simple, low-cost activities, reflecting on the success or failure of the prior prediction, and analysis of the activity to illustrate the correct conception of the flow. Course evaluations indicate that students have found this approach very helpful in improving their conceptual understanding in an introductory engineering fluid mechanics class. [ABSTRACT FROM AUTHOR]

Arc chutes comprising ferromagnetic splitter plates are common in SF6-insulated medium-voltage switchgears. By splitting and cooling the electric arc, they help to interrupt moderate currents such as the rated current in load break switches or the transfer current in switch–fuse combinations. Between the splitter plates of such an arc chute, the motion of the arc depends on the balance of the attracting magnetic forces from the ferromagnetic plates, the repelling forces between two arc columns at the two sides of a plate, and the viscous forces from the insulating gas. We simulated this motion by calculating the magnetic forces acting on the arc columns after splitting by means of 2-D and 3-D electromagnetic finite-element analyses and by taking the viscous force as drag force into account. This paper describes this calculation method and compares the simulation results with those of laboratory tests. [ABSTRACT FROM AUTHOR]

This article highlights several issues related to the collection of post-release outcome data in the evaluation of correctional education programs and identifies the strengths and weaknesses of the different methods of collecting data related to recidivism, employment/earnings, and :further education/training. The use of traditional follow-up in the evaluation of correctional education programs is also discussed. Specific steps to develop a proactive approach to correctional education program evaluation are provided for correctional education administrators. This article would be of interest to correctional education administrations, individuals responsible for the evaluation of correctional education programs, and correctional education researchers. The information provided in this article can be used for both formative and summative evaluation, program planning, decision making, and determining the future direction of correctional education programs. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Awareness and the use of nutritional supplementation for age-related macular degeneration (AMD) patients," by M. Waisbourd and colleagues.

Janis Stradins (10.12.1933 – 29.11.2019) was a well-known expert in molecular electrochemistry, ESR spectroscopy and physical organic chemistry, as well as in history of sciences. His main works in electrochemistry were connected with organic molecules single electron reduction and oxidation primary and secondary products studies, these species ESR spectra hyperfine structure investigations, supplying data on various organic molecules groups' reactivity, demonstrating abilities of electrochemical studies for organic compounds reaction prediction. He was ISE member, past president of Latvian Academy of Sciences, full member of European Academy of Sciences and Arts, from 2011 its Honorary Senator. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article eccentric macular hole formation associated with macular hole surgery.