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Physics Education Research has a rich history of identifying common student ideas about specific physics topics. In the context of electric circuits, existing research on students' ideas has primarily focused on misconceptions, misunderstandings, and difficulties. In this paper, we take a resource-oriented approach to identifying common student ideas about circuits by characterizing ideas we see as generative "seeds of science" that could form the basis of more sophisticated understandings. Based on our analysis of 1557 university physics student responses to five conceptual questions, we identify four common resources for understanding circuits.

Literature on student ideas about circuits largely focuses on misunderstandings and difficulties, with seminal papers framing student thinking as stable, difficult to change, and connected to incorrect ontological categorizations of current as a thing rather than a process. In this paper, we analyzed 417 student responses to a conceptual question about electric circuits using a lens consistent with resources theory. We found that though indicators of substance-based reasoning about current are common in student responses, this reasoning is not predictive of other difficulties reported in the literature, such as "current is consumed" or "the battery is a constant source of current." We also found that students use substance-based reasoning in resourceful ways, suggesting that substance-based reasoning may in fact be a productive starting place for instruction on circuits.

As data and protocols are increasingly generated, accessed, and manipulated electronically, many labs are shifting to storing data in electronic laboratory notebooks (ELNs). ELNs provide clear advantages in readability, shareability, searchability, accessibility, and data security over their paper counterparts. Our interdisciplinary program implemented ELNs across several sections of our gateway molecular biology laboratory course and analyzed the impact on 384 students (13 sections total from Fall 2016 to Spring 2018) using surveys, focus groups, and grade data. We found that students prefer the electronic format, citing the ease of transitioning to lab reports and the longevity of their data. Course grades overall were not affected by the change. Based on our experience, we offer suggestions for smoothing the transition to an ELN system in undergraduate and graduate laboratory courses, including use during remote teaching.

[This paper is part of the Focused Collection on Qualitative Methods in PER: A Critical Examination.] Identifying student ideas about particular physics topics is one of the earliest and longest-standing foci of physics education research. This paper presents a method for identifying common conceptual resources for understanding physics, using large numbers of written student responses to conceptual questions. We walk researchers step by step through how we have done this ourselves, from collecting data, to identifying candidate resources, to turning our lists of candidate resources into a coding scheme that can then be applied to datasets of >200 responses. The outcome of these methods are lists of common conceptual resources for understanding particular topics in physics, such as forces, energy, circuits, and heat and temperature.

BackgroundFace masks, also referred to as half masks, are essential to protect healthcare professionals working in close contact with patients with COVID-19-related symptoms. Because of the Corona material shortages, healthcare institutions sought an approach to reuse face masks or to purchase new, imported masks. The filter quality of these masks remained unclear. Therefore, the aim of this study was to assess the quality of sterilized and imported FFP2/KN95 face masks.MethodsA 48-minute steam sterilization process of single-use FFP2/KN95 face masks with a 15 minute holding time at 121°C was developed, validated and implemented in the Central Sterilization Departments (CSSD) of 19 different hospitals. Masks sterilized by steam and H2O2 plasma as well as new, imported masks were tested for particle filtration efficiency (PFE) and pressure drop in a custom-made test setup.ResultsThe results of 84 masks tested on the PFE dry particle test setup showed differences of 2.3±2% (mean±SD). Test data showed that the mean PFE values of 444 sterilized FFP2 face masks from the 19 CSSDs were 90±11% (mean±SD), and those of 474 new, imported KN95/FFP2 face masks were 83±16% (mean±SD). Differences in PFE of masks received from different sterilization departments were found.ConclusionFace masks can be reprocessed with 121 °C steam or H2O2 plasma sterilization with a minimal reduction in PFE. PFE comparison between filter material of sterilized masks and new, imported masks indicates that the filter material of most reprocessed masks of high quality brands can outperform new, imported face masks of unknown brands. Although the PFE of tested face masks from different sterilization departments remained efficient, using different types of sterilization equipment, can result in different PFE outcomes.

Background: Previous research suggested that persons with Down syndrome (DS) used a different strategy to drum than typical adults. Methods: The present study examined continuous bimanual drumming strategies in response to different instructions in 10 persons with DS, 10 mental age-matched and 10 chronological age-matched groups. The drumming task required participants to hit two drums with the drumsticks at the same time following verbal (e.g. "up" and "down"), visual (e.g. video of both drumsticks moving up and down together) or auditory (e.g. sound of both drums being hit, then cymbal being hit) instructions for 10 s. Sensors placed on the wrists of each participant and the end of each drumstick provided data that allowed the assessment of individual drumming strategies. Results: In general, when persons with DS were following the visual instructions their drumming movements were shorter, straighter and less variable as compared with their movements in the auditory and verbal conditions. Conclusions: Whether movement paths were straight or curved, the strategy was to move the drumstick and wrist together as one unit.

Trace element analysis was conducted on ceramics from Mississippian Caborn-Welborn sites located in the lower Ohio River Valley. Elemental concentrations were measured for each sherd using both neutron activation analysis (NAA) and particle-induced X-ray emission (PIXE). By using principal components analysis and posterior discriminant analysis, it was possible to compositionally distinguish lower Ohio Valley ceramics from ceramic samples collected from archaeological sites located in the southeastern part of the United States. Similar statistical analyses applied to an examination of the elemental composition of Caborn-Welborn ceramics and their distribution within the Caborn-Welborn region documented minimal variation between the samples based on either site location or ceramic type. Ceramics classified as Caborn-Welborn as well as central Mississippi Valley types and Oneota-like sherds recovered from Caborn-Welborn sites appear to have been locally produced from similar clays. However, the clays used to produce ceramic vessels differed from those used as daub on house walls. [ABSTRACT FROM AUTHOR]