Biomaterials For Small Tools

非技术性：俄勒冈州大学尤金材料研究部生物材料项目的这一奖项旨在研究小型生物体中进化出的机械和材料适应性，以科普整体工具上的缩放规则，以及超微结构和分子尺度。当农民的收割工具变钝时，他们可以被磨尖或更换。然而，这些选择对许多动物来说是不可能的。他们必须依赖那些注定会随着每次使用而降低效率的工具。这对于像蜘蛛和昆虫这样的小动物来说尤其成问题，它们依赖工具的锋利来克服与它们的大小相关的力的限制。 这可能是奇怪的材料，含有高达25%的锌，铁，铜，锰，碘和溴，在许多小动物的牙齿，下巴，爪子和刀片中发现，通过减少磨损和骨折来应对这一挑战。该项目将研究这些材料的特性，并详细调查其组成。新的理解可以从这些材料中学习，这些材料在小生物体中进化，以满足与小规模机械相互作用相关的独特挑战。此外，类似的材料可以应用于锋利的工具，例如医疗器械（例如解剖刀和微型“机器人”），原子力显微镜尖端，或需要坚硬但耐冲击材料的其他应用。该项目将为研究教育提供巨大的机会，因为它是跨学科的，结合了材料科学，生物学，化学和物理学的方法。这项研究将与教学和培训研究生和本科生在这一跨学科领域相结合。技术：锋利的工具使较小的动物（和小，力有限的机器）能够切割和穿刺相同的材料，因为他们的更大和更强的同行。 蚊子和狮子都要刺穿同一块皮肤，树懒和切叶蚁都要切下同一片叶子。但是随着工具半径变小，使工具断裂所需的能量比用工具刺穿膜所需的能量变小且更快，使得断裂的可能性越来越大。提议者将研究在小生物中进化的机械和材料适应，以科普整个工具，超微结构和分子尺度上的这种缩放规则。拟议的活动将：1）首次在小动物中测试用于机械结构的几种重元素生物材料（HEB）的机械性能; 2）测试一种新的缩放规则，表明较小的动物需要更抗断裂的工具; 3）开始测试新的假设，即重原子可以用于降低分子共振频率，从而抑制冲击引起的高频振动; 4）测试水结合的变化与HEB中硬度和抗断裂性的平衡相关的假设; 5）基于HEB在生物工具中的位置，测试特定HEB的机械性能的平衡的预测;以及6）测试特定的锌结合假设。该奖项的研究人员将使用他们已经开发或将要开发的工具来测量小样本的机械性能，以及先进的化学技术，如原子探针断层扫描。该项目将提供这些尖端技术的研究培训，并获得跨学科研究的专业知识。代表性不足和非传统的学生将积极招募和指导，并将通过与当地社区学院的实习计划提供参与这项研究的机会。研究生和本科生将接受从本项目的成果开发的课程的研究培训。

Nontechnical: This award by the Biomaterials Program in the Division of Materials Research to University of Oregon Eugene is to study the mechanical and material adaptations that have evolved in small organisms to cope with the scaling rule on the whole-tool, and at ultrastructural and molecular scales. When a farmer's harvesting tools get dull, they can be sharpened or replaced. However, these options are not available to many animals. They must rely on tools that are doomed to become less efficient with each use. This is especially problematic for small animals like spiders and insects that rely on the sharpness of their tools to overcome the force limitations associated with their size. It may be that the strange materials, containing up to 25% of zinc, iron, copper, manganese, iodine and bromine that are found in the teeth, jaws, claws and blades of many small animals have evolved to meet this challenge by reducing wear and fracture. This project will study the properties of these materials, with a detailed investigation of their composition. New understanding may be learned from these materials that have evolved in small organisms to meet their distinctive challenges associated with small-scale mechanical interactions. Furthermore, similar materials may find application in sharp tools such as medical devices (e.g. scalpels and miniature "robots"), atomic force microscopy tips, or in other applications that require hard but impact resistant materials. The project will provide great opportunities for research education because it is so interdisciplinary, combining methods from material science, biology, chemistry and physics. This research will be integrated with teaching and training graduate and undergraduate students in this interdisciplinary area.Technical: Sharper tools enable smaller animals (and small, force-limited machines) to cut and puncture the same materials as their larger and stronger counterparts. A mosquito and a lion both puncture the same skin, a sloth and a leaf cutter ant must both cut the same leaves. But as the tool radius gets smaller, the energy required to fracture the tool gets smaller and faster than the energy required to puncture the membrane with the tool, making fracture increasingly likely. The proposers will study the mechanical and material adaptations that have evolved in small organisms to cope with this scaling rule on the whole-tool, ultrastructural, and molecular scales. The proposed activity will: 1) test, for the first time, the mechanical properties of several Heavy Element Biomaterials (HEBs) used in mechanical structure in small animals; 2) test a novel scaling rule suggesting that smaller animals need more fracture resistant tools; 3) begin to test the novel hypothesis that heavy atoms can be used to lower molecular resonant frequencies and thereby damp the high frequency vibrations from impact; 4) test the hypothesis that variations in water binding are correlated with the balances of hardness and fracture resistance in HEBs; 5) test predictions of the balance of mechanical properties in particular HEBs, based on their locations in biological tools; and 6) test a specific zinc binding hypothesis. The researchers of this award will use tools that they have developed or will be developing for measuring mechanical properties of small specimens, as well as advanced chemical techniques such as Atom Probe Tomography. This project will provide research training in these cutting edge technologies as well as gain expertise in interdisciplinary research. Underrepresented and nontraditional students will actively recruited and mentored, and will provide opportunities to participate in this research through an internship program with a local community college. Graduate and undergraduate students will receive research training in a course developed from the outcome of this project.