Individualized assignments, group work and discussions. How they interact with class size, low socioeconomic status, and second language learners

Varied teaching techniques are an important aspect of a successful classroom. Student and classroom factors such as ability level, lower socioeconomic status, and/or native language can interact with teaching techniques. Previous work suggests that each teaching technique may be more effective for different students or in different classroom situations, but few studies have directly examined which factors relate to effective teaching techniques. This study uses data for early secondary school students in Germany from the National Education Panel Study (NEPS) to examine the effects of group work, discussions, and individualized assignments on reading and math competency change between 7th and 9th grade. Additionally, we model the interactions of effects of class size, second language learners background, and lower socioeconomic status with these teaching techniques. We conclude that group work relates to more competency growth in math for second language learners, while classroom discussions relate to less growth for second language learners. Discussions relate to less growth in math competency for smaller classes and more growth in larger classes. Group work was also related to slower reading competency growth for children with a higher prior ability level. Findings are discussed in relation to existing theories of teaching techniques

Advancing the automation of plant nucleic acid extraction for rapid diagnosis of plant diseases in space

Human space exploration missions will continue the development of sustainable plant cultivation in what are obviously novel habitat settings. Effective pathology mitigation strategies are needed to cope with plant disease outbreaks in any space-based plant growth system. However, few technologies currently exist for space-based diagnosis of plant pathogens. Therefore, we developed a method of extracting plant nucleic acid that will facilitate the rapid diagnosis of plant diseases for future spaceflight applications. The microHomogenizer™ from Claremont BioSolutions, originally designed for bacterial and animal tissue samples, was evaluated for plant–microbial nucleic acid extractions. The microHomogenizer™ is an appealing device in that it provides automation and containment capabilities that would be required in spaceflight applications. Three different plant pathosystems were used to assess the versatility of the extraction process. Tomato, lettuce, and pepper plants were respectively inoculated with a fungal plant pathogen, an oomycete pathogen, and a plant viral pathogen. The microHomogenizer™, along with the developed protocols, proved to be an effective mechanism for producing DNA from all three pathosystems, in that PCR and sequencing of the resulting samples demonstrated clear DNA-based diagnoses. Thus, this investigation advances the efforts to automate nucleic acid extraction for future plant disease diagnosis in space