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Distribution of Native Dandelions on the Campus of Yokohama National University and Its Application to Citizen Science
Full text link生物多様性国家戦略では，日本における生物多様性の危機として4 つの要因を挙げている（環境省，2012）。その中の1 つに「外来種による危機」があり，環境省は日本の生物多様性を脅かす外来生物について「生態系被害防止外来種リスト（環境省，2014）」を公表し，注意を呼び掛けている。わたしたちに身近なタンポポは，現在ではそのほとんどが外来性タンポポと在来種の交雑により生じた雑種個体と言われており，外来性タンポポ種群として重点対策外来種に挙げられている。このような誰でも知っている身近な種に着目して外来生物による危機を通して一般化することで，生物多様性保全への理解を深められる可能性がある。本研究ではこれまで判定の主流であった総苞外片の形状だけでなく，花粉形態による分類で雑種個体の識別を行い，外部形態では識別できなかった身近な環境に入り込んだ外来種の生態を知るための市民調査，学校での教材化の可能性について検討した
Why Does the Rate of Non-Readers Increase from Junior High to High School?: Consideration by Textual Analysis
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Low-melting, ether-functionalised lithium salts for enhanced ion transport in molten salt electrolytes
Full text linkWe report ether-functionalised lithium salts as molten salt electrolytes for Li-ion batteries. Flexible ether chains in asymmetric anions suppress crystallinity and promote nano-segregation, lowering melting points below 100 °C. In the molten state, they deliver high ionic conductivity and near-unity Li+ transference numbers, establishing a molecular design principle for high-performance, solvent-free electrolytes for next-generation energy storage
Gas-sheared falling liquid films beyond the absolute instability limit
Full text linkWe study the effect of a confined turbulent counter-current gas flow on the waviness of a weakly-inclined falling liquid film. Our study is centered on experiments in a channel of 13 mmheight, using water and air, where we have successively increased the counter-current gas flow rate until flooding. Computations with a new low-dimensional model and linear stability calculations are used to elucidate the linear and nonlinearwave dynamics.We find that the gas pressure gradient plays an important role in countering the stabilizing effect of the tangential gas shear stress at the liquid-gas interface. At very low inclination angles, the latter effect dominates and can suppress the long-wave Kapitza instability unconditionally. By contrast, for non-negligible inclination, the gas-effect is linearly destabilizing, amplifies the height of nonlinear Kapitza waves, and exacerbates coalescence-induced formation of large-amplitude tsunami waves. Kapitza waves do not undergo any catastrophic transformation when the counter-current gas flow rate is increased beyond the absolute instability (AI) limit. On the contrary, we find that AI is an effective linear wave selection mechanism in a noise-drivenwave evolution scenario, leading to highly regular downward-travelling nonlinearwave trains, which preclude coalescence events. In our experiments, where Kapitza waves develop in a protected region before coming into contact with the gas, flooding is eventually caused far beyond the AI limit by upward-travelling short-wave ripples. Based on our linear stability alculations for arbitrary wave numbers, we have uncovered a new short-wave interfacial instability mode with negative linear wave speed, causing these ripples
