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A Correction to this paper has been published: https://doi.org/10.1038/s42005-021-00578-4

Students investigate energy conversions by collaborating to develop a free standing track of plastic tubing through which a ball bearing moves at the fastest possible speed. Friendly competition leads to discussion of what worked and did not work and to the identification and investigation of underlying principles. (Contains 4 charts.)

Three sample preparation methods (wet grinding followed by centrifugation, ultrasonic-assisted extraction and microwave-assisted solvent extraction) for extracting ascorbic acid (AA) from parsley, dill and celery were evaluated. AA was extracted into 8% aqueous solutions of acetic acid, metaphosphoric acid and trichloroacetic acid, respectively. An efficient and precise high-performance liquid chromatography method was used for detecting AA. The best extraction technique was ultrasonic-assisted extraction, and acetic acid was the best extractant. A new and original pulse microwave-extraction procedure for AA extraction was also developed. Ascorbate from the plant extracts obtained was quantified and the linearity, precision, recovery, limit of detection (LOD) and limit of quantification (LOQ) were studied. LOD and LOQ were 0.2 and 0.22 mg/L for the established method, respectively. The mean recovery ranged from 90.7 to 102.3% with higher variation in the case of celery. Parsley contains the highest amount of ascorbic acid (264 mg AA/100 g of fresh plant), followed by dill (121 mg AA/100 g of fresh plant) and celery (103 mg AA/100 g of fresh plant). Keywords: HPLC, ascorbic acid, vitamin C, extraction, sample preparation, parsley, dill, celery DOI: 10.1134/S106193481410013X, Vitamin C, also known as ascorbic acid, L-ascorbic acid or L-ascorbate, is the most important vitamin for human nutrition that is supplied by fruits and vegetables. Actually, vitamin C is [...]

"The National Science Education Standards" direct science educators to employ inquiry as a basic teaching strategy, and to place more emphasis on understanding student needs, abilities, and interests, and actively engaging in scientific investigations. Although they generally accept this emphasis as desirable, educators--particularly new educators--have differing notions about what inquiry really is and are often unsure about what effective science inquiry looks like when classes are large and supply budgets are small. The immersion activity provides a doable challenge that overcomes the reluctance of those students least likely to be interested in a more formal activity, and becomes a valuable common referent that all students in class can later recall and consider. With this immersion activity completed and discussed, teachers can then guide students in selecting and developing an investigation of interest that clarifies and applies the principles under consideration. Assessment addresses how well the procedure that students developed and followed applies to the research question. An evaluation rubric aids greatly in this type of assessment and, if given in advance, can give helpful direction to students as they develop their investigation plan. (Contains 2 figures.)

Evaluated the effect on French language proficiency of an integrated formal, analytic and functional, communicative approach to second language teaching in the immersion classroom. Impetus for the study arises from previous research indicating that immersion children show persistent weaknesses in their grammatical skills despite the fluent, functional proficiency they achieve in their second language. (Author/VWL)

Introduces an activity on the rock cycle. Sets 11 stages representing the transitions of an earth material in the rock cycle. Builds six-sided die for each station, and students move to the stations depending on the rolling side of the die. Evaluates students by discussing several questions in the classroom. Provides instructional information for the activity. (YDS)

Analysis of minutes of board of education meetings in all 31 rural Utah school districts found that rural boards tended to micromanage their districts, generally ignoring the larger leadership function of building consensus and fostering a sense of community. Discussions of educational reform movements and unstructured discussion with patrons received low priority. Contains 24 references. (TD)

A study of French immersion teacher education programs at Simon Fraser University and Faculte Saint-Jean (University of Alberta) in Canada is reported. The in-depth case studies examined program clientele, models, participant experiences and needs, and planning, especially in relation to current research on teacher education. (Author/MSE)

High efficiency space solar cells based on the GaInP2/InGaAs/Ge triple junction lattice matched device with 1 sun, AM0 efficiencies of approximately 30% are commercially available from several companies. Multiple approaches have been suggested for significantly surpassing the 30% efficiency level, but achieving this in a commercially viable cell has not been easy. We review those approaches, pointing out the advantages and challenges of each. SolAero has been focused on developing the inverted metamorphic multi-junction (IMM) solar cell, and has recently demonstrated a radiation hard version. We present the most recent performance data, including the response to particle radiation. The IMM cell can be used in a number of rigid or flexible configurations, and considerable effort has been focused on cell packaging and panel integration. The IMM device is ready to start qualification to the ECSS and AIAA standards.

An experimental study was designed to evaluate the effect on French language proficiency of an integrated, formal, analytic and functional, communicative approach to second-language teaching in French immersion. The study consisted of 315 grade 7 early French immersion students. (28 references) (VWL)