initial gas filling of the tracheal system (tracheal filling) in embryos of the tobacco hornworm Manduca sexta (Sphingidae, Insecta). Main focus is the role of cavitation and the importance of solid/liquid/gas interactions at the tracheal wall.

烟草天蛾Manduca sexta（天蛾科，昆虫纲）胚胎中气管系统的初始气体填充（气管充盈）。

• 批准号: 201264169
• 负责人: Dr. Thomas Förster
• 金额: --
• 依托单位: Division of Biological Sciences
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 无数据
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/201264169?language=en
• 关键词: initial; gas; filling; tracheal; system

Embryos of the tobacco hornworm (Manduca sexta) render their tracheal system functional while developing in the egg. The process is remarkable for two reasons. First, tracheal gas filling occurs without contact to outside air; gas bubbles are generated de novo in liquid. Second, the process is very fast. The tracheal system becomes functional in less than five minutes. This indicates that cavitation triggers tracheal filling.The project serves to understand cavitation in the tracheal system of Manduca embryos in unprecedented detail by manipulating factors that affect the likelihood or timing of cavitation. Those factors are the pressure inside the egg, the micro-structure of the tracheal wall, and the change in the surface chemistry of the wall that occurs with sclerotization of the cuticle.A second goal is to uncover the mechanism by which the tracheal liquid is eliminated from the tracheal lumen after cavitation has occurred. Two main alternatives exist. First, water may disappear through the whole tracheal wall. The wall has relatively large surface area, but the sclerotized cuticle is supposed to be impermeable to water. Second, water may disappear only at the tips of the tracheae (tracheoles), where the cuticle is thin and unsclerotized.Tracheal filling provides a biological example of strong surface forces arising from solid-liquid-gas interactions. The proposed project will give insight into the role these three-phase interactions play during a critical respiratory transition in insects. In addition, these kinds of interactions are fundamental in materials science (functional surfaces, lotus effect) and micro-fluidics (lab-on-a-chip applications). We think that detailed study of how biological evolution has shaped these interactions may illuminate basic engineering problems of wide interest.

烟草天蛾（Manduca sexta）的胚胎在卵中发育时使其气管系统发挥功能。这一过程之所以引人注目，有两个原因。首先，气管气体填充在不接触外部空气的情况下发生;气泡在液体中重新产生。第二，这个过程非常快。气管系统在五分钟内就能正常工作。这表明，空化触发气管填充。该项目通过操纵影响空化可能性或时间的因素，以前所未有的详细程度了解Manduca胚胎气管系统中的空化。这些因素包括卵内的压力、气管壁的微观结构以及表皮硬化时发生的壁表面化学变化。第二个目标是揭示发生空化后气管液体从气管腔中排出的机制。存在两种主要的替代方案。首先，水可能会通过整个气管壁消失。壁具有相对大的表面积，但硬化角质层应该是不透水的。第二，水可能只在气管的顶端（气管）消失，那里的角质层很薄，没有角质层。气管填充提供了一个由固液气相互作用产生的强大表面力的生物学例子。拟议的项目将深入了解这些三相相互作用在昆虫关键的呼吸过渡期间所起的作用。此外，这些类型的相互作用是材料科学（功能表面，莲花效应）和微流体（芯片实验室应用）的基础。我们认为，对生物进化如何塑造这些相互作用的详细研究可能会阐明广泛关注的基本工程问题。