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Information-theory-based System-level Babcock–Leighton Flux Transport Model–Data Comparisons
No full textSystem-level Babcock–Leighton flux transport model–data comparisons are performed using information theory. The model is run with a maximum meridional flow speed of 16.5 m s−1 with the flow speed systematically varied by 20% (BLFT20) and 50% (BLFT50). Overall, the comparisons show that the models qualitatively capture much of the information flow among the toroidal field (sunspot number), polar field, and meridional flow. BLFT20 generally compares better than BLFT50, suggesting that meridional flow variation of 20% may be more realistic than 50%. However, the information flow from the meridional flow to the polar field is captured better in BLFT50. There is more information flow from the sunspot number to the polar field than the other way around in BLFT20 and observations. The information flow from the polar field to the sunspot number peaks at lag times (τ) of ∼2 yr and 7–9 yr in observations and BLFT20. The results can shed light on the nature of the Sun’s magnetic memory, the diffusive/dissipative processes, and advection in the turbulent flux transport at the Sun
Systematics and Biogeography of Bacopa (Plantaginaceae)
No full textThe aquatic and wetland plant genus Bacopa contains species that are found worldwide, with a center of diversity in the Americas. Although there have been regional taxonomic studies of the genus, a global synthesis is lacking. Variation in morphological features across species has complicated efforts to determine species boundaries and circumscribe infrageneric categories with confidence. Molecular data have enabled a more thorough understanding of phylogenetic relationships in Bacopa, and these can be used to develop a more stable taxonomy for the genus. Because there are approximately 60 species in the genus, it would be helpful to have a phylogenetically informed sectional classification and an improved understanding of ancestral biogeography and morphological evolution. We obtained novel molecular data for 28 species and produced phylogenetic hypotheses that include most species in the genus. The phylogenetic evidence supports at least four independent transitions to becoming fully aquatic species. We also reconstructed three separate ancestral dispersal events into Africa and beyond. Morphometric data were used to evaluate species boundaries and synonymy. We update sectional circumscriptions and propose a new section, Bacopa sect. Conobea, to accommodate species formerly in the genus Conobea that were found to be monophyletic with Bacopa
Teachers\u27 Accountability for Student-centered Learning in Adventist Secondary Schools in West Kenya Union Conference: Toward Better Learning Outcomes
No full textThis study probes the association of teachers’ accountability for designing a student- centered curriculum with student’s academic achievement in the Adventist secondary schools in the western Kenya region. It was found that teachers in high-performing schools are more accountable for student-centered learning implying that accountability results in better learning outcomes