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Purpose: This study aimed to examine how physical education teacher education (PETE) programs prepare preservice physical education teachers (PPETs) for implementing health-related fitness testing (HRFT) in K-12 schools from a faculty perspective. Methods: The study applied a phenomenological approach. Seven PETE faculty participated in this study. Data were collected through semistructured interviews, online surveys, and course documents. Constant content analysis was performed to generate themes. Results: The study discovered four themes: (a) required courses are the primary means for preparing PPETs to use HRFT, (b) cooperating teachers can negatively influence the faculty's role in HRFT preparation, (c) PPETs explored the use of HRFT in PETE programs through peer teaching and testing activities, and (d) there was a lack of field-based experiences in local schools for HRFT preparation. Conclusion: PETE programs provided some courses to prepare PPETs for the HRFT implementation with the lack of time and field experience.

The ability to step quickly in response to a perturbation has been shown to be critical for prevention of falls. The cognitive processing, weight shifting, and locomotion must be well timed to execute a successful step. The purpose of this study was to compare the response preparation and response execution processes between a simple (SRST) and a choice reaction stepping task (CRST). Nine healthy young subjects were recruited to participate in this study. Subjects were required to stand on a forceplate and maintain their balance, and step forward on a second forceplate with either the left or right foot after hearing an auditory tone. The center of pressure (COP) was analyzed to determine the types of anticipatory postural adjustment (APA) prior to a step. The APA phase and stepping phase timing was calculated based on the COP trajectory. Findings showed that reaction time (RT), APA phase and overall stepping latency were slower for CRST than for SRST. We also identified an intermediate type of APA response (posterior shift APA) in addition to the correct and error APA response, and found the posterior shift APA response had the fastest execution time for CRST, and may be beneficial for falls prevention. [ABSTRACT FROM AUTHOR]

The Escherichia coli protein WrbA, an FMN-dependent NAD(P)H:quinone oxidoreductase, was crystallized under new conditions in the presence of FAD or the native cofactor FMN. Slow-growing deep yellow crystals formed with FAD display the tetragonal bipyramidal shape typical for WrbA and diffract to 1.2 Å resolution, the highest yet reported. Faster-growing deep yellow crystals formed with FMN display an atypical shape, but diffract to only ∼1.6 Å resolution and are not analysed further here. The 1.2 Å resolution structure detailed here revealed only FMN in the active site and no electron density that can accommodate the missing parts of FAD. The very high resolution supports the modelling of the FMN isoalloxazine with a small but distinct propeller twist, apparently the first experimental observation of this predicted conformation, which appears to be enforced by the protein through a network of hydrogen bonds. Comparison of the electron density of the twisted isoalloxazine ring with the results of QM/MM simulations is compatible with the oxidized redox state. The very high resolution also supports the unique refinement of Met10 as the sulfoxide, confirmed by mass spectrometry. Bond lengths, intramolecular distances, and the pattern of hydrogen-bond donors and acceptors suggest the cofactor may interact with Met10. Slow incorporation of FMN, which is present as a trace contaminant in stocks of FAD, into growing crystals may be responsible for the near-atomic resolution, but a direct effect of the conformation of FMN and/or Met10 sulfoxide cannot be ruled out. [ABSTRACT FROM AUTHOR]

Cells often spatially organize biomolecules to regulate biological interactions. Synthetic mimicry of complex spatial organization may provide a route to similar levels of control for artificial systems. As a proof-of-principle, we constructed an RNA-extruding nanofactory using a DNA-origami barrel with an outer diameter of 60 nm as a chassis for integrated rolling-circle transcription and processing of RNA through spatial organization of DNA templates, RNA polymerases, and RNA endonucleases. The incorporation efficiency of molecular components was quantified to be roughly 50% on designed sites within the DNA-origami chassis. Each integrated nanofactory with RNA-producing units, composed of DNA templates and RNA polymerases, produced 100 copies of target RNA in 30 min on average. Further integration of RNA endonucleases that cleave rolling-circle transcripts from concatemers into monomers resulted in 30% processing efficiency. Disabling spatial organization of molecular components on DNA origami resulted in suppression of RNA production as well as processing.