Physics of Wear, Tear, Aging and Failure in Living and Nonliving Systems Conference

生物老化的特征是结构完整性丧失和功能随时间的下降。人们普遍认为，这些变化随着年龄的增长而逐渐发生，最终导致生物体的死亡。工程物理系统也会随着时间的推移而改变，再次失去结构完整性，最终无法执行其设计功能。本次研讨会将探讨关于这些过程的一般思想在多大程度上可以应用于生命和非生命系统。关于生物衰老的潜在机制有许多建议，其中大多数集中在一个单一的分子过程。例如，端粒缩短作为细胞衰老的一个非常特殊的驱动因素，已经进行了大量的研究。然而，这项工作的大部分都回避了一个核心问题，即衰老是生命中发生的物理和化学过程的不可避免的结果，还是细胞正在执行的遗传和/或表观遗传程序的可修改结果。大多数工程系统的失败不是因为其部件事先程序化的退化，而是因为复杂系统相互作用时发生的自然物理过程。生命系统是否相似？这些都是研讨会将要讨论的问题。物理系统中发生的老化过程有几种类型。侵蚀、腐蚀和结构缺陷的形成是导致物理器件结构完整性降低、保真度降低和最终失效的一些机制。不同的系统受制于这些基本机制的不同混合。在生命系统中，生物体的不同部分年龄不同。例如，免疫系统、皮肤和其他需要不断更新细胞的器官，被认为是由于细胞增殖能力下降而老化的。尽管存在许多“理论”，说明细胞内发生的物理和化学过程如何导致这种减少，但细胞内导致构成组织的细胞增殖能力降低的机制尚不清楚。另一方面，动物的膝盖以不同的方式衰老。在这种情况下，持续使用带来的摩擦导致软骨磨损，逐渐变得越来越难作为关节使用。在衰老的第一个例子中，器官随着时间的推移变得更容易受到各种疾病的影响，并最终导致与疾病相关的死亡。在第二种情况下，动物无法与捕食者竞争，被它们吃掉。当生物和机械系统的部件出现故障时，它们可以而且经常被修复。然而，从本质上讲，修复过程也容易出错，而且不可能无限期地保持下去。50年代的车有多少还在使用？这似乎在个体水平和物种水平上都是正确的。但是，如果我们把生命作为一个整体来考虑，进化似乎打破了这个基本的限制，地球上的生命在地球历史的大部分时间里都是繁荣的。这只是我们有限的生命经验的问题，还是进化总能找到一个可行的策略？本次研讨会将于2015年5月7日至8日在弗吉尼亚州泰森斯角举行。大约25位代表物理学、材料科学和生物学的科学家将讨论生命和非生命系统老化的物理原理和过程，生命和非生命系统之间的异同以及它们的修复和失效。研讨会参与者将讨论非平衡热力学与衰老之间的关系，信息理论在描述衰老过程中的作用，以及这些信息如何在整个生命中保存，最后，我们可以从生命系统中学习到强大的技术开发经验。研讨会特别寻求在研讨会上有年轻科学家的代表，他们将带来他们对衰老的看法，并向更有经验的同事学习。

Biological aging is characterized by loss of structural integrity and functional decline with time. It is generally believed that these changes occur gradually with age, leading to the eventual death of the organism. Engineered physical systems also change as time passes, again losing structural integrity and eventually failing to perform their designed function. This workshop will explore the extent to which general ideas regarding these processes can be applied to both living and nonliving systems. There have been many proposals regarding the underlying mechanisms of biological aging, most of which focus on a single molecular process. For example, much work has gone into the issue of telomere shortening as a very specific driver of cellular senescence. However, much of this work begs the central question of whether aging is an inevitable consequence of the physical and chemical processes that take place during life or alternatively whether it is a modifiable consequence of a genetic and/or epigenetic program that is being executed by the cells. Most engineered systems fail not because of prior programmed deterioration of its parts, but because of the natural physical processes that take place when complex systems interact with each other. Are living systems similar? These are the questions that the workshop will address. There are several types of aging processes that take place in physical systems. Erosion, corrosion, and structural defect formation are some of the mechanisms contributing to diminished structural integrity, decrease in fidelity and eventual failure of physical devices. Different systems are subject to different mixes of some of these fundamental mechanisms. In living systems, different parts of an organism age differently. For example, the immune system, the skin, and other organs subject to continuous cell renewal, are believed to age due to diminishing cell proliferative capacity. The intracellular mechanisms responsible for the reduction of the proliferative potential of the cells comprising the tissue are not well understood, although many "theories" exist of how such reduction could be brought by the physical and chemical processes taking place in a cell. On the other hand the knee of an animal ages in a different manner. In this case the friction brought by continuous use leads to wear of the cartilage, and it gradually becomes harder and harder to use as a joint. In the first example of aging the organs become more susceptible with time to various diseases and eventually lead to disease related death. In the second case the animal cannot compete with its predators and gets consumed by them. As their parts fail, biological and mechanical systems can and often are repaired. However, the repair process is also by its nature prone to errors, and cannot keep up indefinitely. How many cars from the 1950's are still operational? This seems to be true both at the individual level and at the species level. But, if we consider life as a whole, evolution seems to have defied this fundamental limitation and life on Earth has been flourishing for most of the history of the planet. Is this just a question of our limited experience with life or will evolution always find a viable strategy. In this workshop that will take place May 7 - 8, 2015 at Tysons Corner in Virginia. Approximately 25 scientists representing Physics, Materials Science, and Biology will discuss the physical principles and processes underlying aging in living and nonliving system, the similarities and differences between living and nonliving systems and their repair and failure. The workshop participants will discuss what is the relation between non-equilibrium thermodynamics and aging, is there a role for information theory in describing the aging process and how is this information preserved in life as a whole, and finally are there lessons for robust technology development that we can learn from living systems. The workshop especially seeks to have representation at the workshop of young scientists, who will bring their perspective on aging and learn from more experienced colleagues.