Biomechanicsof Self-Assembly of the Lepidopteran Feeding Device

该项目的总体目标是了解长鼻自组装的生物力学原理，并将这些原理应用于工程基于纤维的自组装微流体装置，以操纵微米和纳米液滴。正在研究的模型系统是蝴蝶的长鼻饲管。成虫从蛹中出来后，通过连接背侧和腹侧帽状腱膜纤维以及角质层硬化，该管被组装和硬化。成熟的长鼻呈卷曲状，但在进食过程中可完全伸展；延伸涉及帽状腱膜纤维的反平行滑动。该项目的目标是（i）研究唾液在产生毛细管压力方面的作用，毛细管压力迫使活体蝴蝶和纤维轨模型系统中的两个帽状突起在一起（弹性毛细管效应），（ii）使用X射线相衬成像研究长鼻组装过程中的唾液行为，（iii）提供长鼻机械和润湿特性的完整表征，以评估模型参数并评估不同模型的适用性。自组装和硬化场景，以及（iv）开发一种依赖于毛细管作用并按照长鼻组装/拆卸原理工作的纤维轨型微流体系统。

The overarching goal of this project is to understand the biomechanical principles of proboscis self-assembly and to apply these principles to engineer fiber-based self- assembling microfluidic devices for manipulation of micro and nano droplets. The model system under investigation is the proboscis feeding tube of butterflies. This tube is assembled and hardened after emergence of the adult from the pupal encasement by joining dorsal and ventral galeae fibers and cuticle hardening. The mature proboscis is coiled but can be fully extended during the feeding process; the extension involves antiparallel sliding of the galeae fibers. The goals of the project are (i) to study the effect of saliva in creating capillary pressure that forces the two galeae together (the elasto-capillary effect) in live butterflies and a model system of fiber rails, (ii) to study saliva behavior during this process of proboscis assembly, using X-ray phase-contrast imaging, (iii) to provide full characterization of mechanical and wetting properties of the proboscis to evaluate the model parameters and assess the applicability of different self-assembling and hardening scenarios, and (iv) to develop a fiber-rail type microfluidic system that that relies on capillary action and would work on the principles of proboscis assembly/disassembly.