Rib kinematics and intercostal muscle function in amniotes

呼吸似乎是我们做的最简单的事情之一，但实际上，胸腔的结构和运动非常复杂。肋骨和相关的肌肉（肋间肌）有助于人类和其他动物的呼吸，但肋骨和肋间肌的确切呼吸作用几个世纪以来一直存在争议。为什么从这些肌肉的结构和与肋骨的连接来推断它们的动作如此困难？答案在于：（1）肋骨形状的3D复杂性;（2）呼吸期间肋骨运动的3D复杂性;（3）肋间肌肉的3D复杂性;以及（4）从胸腔的顶部到底部和前部到后部的所有上述变化。几十年来，对狗和人类的研究终于对这些哺乳动物的呼气和吸气有了坚实的了解，但这项工作进展缓慢而费力。现在，一种新的3D X射线技术，移动形态的X射线重建（XROMM），刚刚问世，将大大加快活体动物骨骼形状和骨骼运动数据的收集。在这个项目中，XROMM将用于确定七个物种的3D肋骨形状，3D肋骨运动和肋间肌肉功能：三只蜥蜴，两只鸟，一只鳄鱼和一只鳄鱼。选择这些动物是因为它们表现出不同的肋骨形状、肋骨关节形态、体型和运动行为（游泳、跑步和飞行）。XROMM的出现将使这七个新物种有可能在三年内增加到目前只有两个物种的知识中。未来，这项工作的成果可用于重建灭绝动物的呼吸系统，特别是与恐龙有争议的呼吸机制有关的呼吸系统。该项目包括为博士后研究员和博士生提供跨学科培训，为K-12教育做出贡献，增加代表性不足的群体的参与，并加强科学基础设施。博士后和研究生将通过与我们在工程，计算机科学和计算与可视化中心的合作者的互动获得跨学科的培训。博士后和研究生将在具体项目中发挥主导作用，指导本科研究人员，并与普罗维登斯公立学校的K-12教师合作。普罗维登斯公立学校系统中超过80%的学生来自代表性不足的群体，超过80%的学生有资格享受免费或减价午餐。科学家们将与K-12教师合作，开发和提供课程和项目，向学生传授动物运动，生物力学和科学方法，如XROMM。为了加强科学基础设施，将改进XROMM技术，并开发新的软件以简化数据分析。所有硬件和软件创新都是公开的，并可供同事使用（通过NSF研究协调网络和www.xromm.org）。该研究生成的完整元数据将立即通过公共在线数据库（xromm.ccv.brown.edu/webportal/）发布。元数据的发布使同事能够看到数据集的内容并提出合作建议。在出版后或10年后，以较早者为准，所有数据将被公开。

Breathing seems like one of the simplest things we do, but actually the structures and motions of the rib cage are enormously complex. Ribs and associated muscles (the intercostal muscles) contribute to breathing in humans and other animals, but the exact respiratory actions of the ribs and intercostal muscles have been controversial for centuries. Why is it so difficult to infer the actions of these muscles from their structure and attachments to the ribs? The answer lies in: (1) the 3D complexity of rib shape; (2) the 3D complexity of rib motion during breathing; (3) the 3D complexity of intercostal muscles; and (4) variation in all of the above from top to bottom and front to back of the rib cage. Decades of work on dogs and humans have finally yielded a solid understanding of exhalation and inhalation in these mammals, but the work has been slow and laborious. Now a new 3D X-ray technology, X-ray Reconstruction of Moving Morphology (XROMM), has just become available and will vastly speed up the collection of data on bone shape and bone motion in living animals. In this project, XROMM will be used to determine 3D rib shape, 3D rib motion, and intercostal muscle function in seven species: three lizards, two birds, an alligator, and a crocodile. These animals were selected because they show a diverse spectrum of rib shapes, rib joint morphologies, body forms, and locomotor behaviors (swimming, running and flying). The advent of XROMM will make it possible to add these seven new species to the current knowledge of just two species, all within just three years. In the future, the results of this work can be used to reconstruct the respiratory system of extinct animals, with particular relevance to the controversial respiratory mechanisms of dinosaurs.The project includes interdisciplinary training for a Postdoctoral Fellow and a doctoral student, contributions to K-12 education, to increasing participation of underrepresented groups, and to enhancing scientific infrastructure. The postdoc and graduate student will gain interdisciplinary training through interactions with our collaborators in Engineering, Computer Science, and the Center for Computation and Visualization. The postdoc and graduate student will take the lead on specific projects, mentor undergraduate researchers, and work with K-12 teachers from the Providence Public Schools. More than 80% of students in the Providence Public School system are from underrepresented groups and more than 80% qualify for free or reduced cost lunch. In cooperation with K-12 teachers, the scientists will develop and deliver lessons and projects to teach the students about animal motion, biomechanics, and scientific methods such as XROMM. Toward enhancing scientific infrastructure, the XROMM technology will be improved and new software developed to simplify the data analysis. All hardware and software innovations are made public and are available to colleagues (through an NSF Research Coordination Network and via www.xromm.org). The complete metadata generated by the study will be published immediately through a public online database (xromm.ccv.brown.edu/webportal/). Metadata publication allows colleagues to see the contents of the data sets and suggest collaborations. After publication or after 10 years, whichever is earlier, all data will be made public.