Theoretical Problems in Biophysics and Condensed Matter

0231631纳尔逊该奖项支持基础理论研究和教育集中在生物物理学问题，软凝聚态物质和第二类超导体的涡旋物理。PI将研究病毒外壳的结构，以了解为什么小病毒是圆形的，而大病毒是多面的。小面化可能与蛋白质壳粒二十面体阵列中嵌入的十二个5倍向错的屈曲转变有关。理论上的进步可以使实验测定的弹性参数的结构数据。PI将探索由于多核苷酸序列变异对马达蛋白阵列的定位效应，例如RNA聚合酶沿DNA链沿着。也将研究单链结合蛋白如Rec A的顺序聚合和DNA杂交体的最大拔出力。此外，软物质凝聚态物理学中的问题也将受到攻击，这些问题包括确定环面上的晶体基态和吸附在负弯曲的“水管工的噩梦”相上的胶体。最后，将继续研究超导体中的涡旋物质，探索具有稀浓度柱状钉的纠缠通量液体对倾斜磁场的不寻常响应（与横向迈斯纳效应有关）。方法将包括统计力学和动力学的分析方法，演化算子的数值对角化和模型系统的计算机模拟，这些模型系统受到生物学，软凝聚态和涡旋物理学问题的启发。 病毒壳屈曲的研究将利用描述薄球壳的非线性弹性方程的浮动网格离散化的丰富经验。PI将寻求从与实验社区的密切联系和积极互动中受益。该奖项支持凝聚态理论的研究生和更高级别的培训。这项工作也可能影响凝聚态物理学以外的领域。了解病毒外壳的变形可以识别弱点（如脊线或晶界），这将允许攻击有害的传染性病原体。 对序列随机性如何影响蛋白质与DNA和RNA相互作用的探索可能会影响细菌中人工遗传电路的设计。 曲面上缺陷阵列的综合理论可以指导以双连续脂相为模板的新材料的构建。 最后，了解涡流与柱状缺陷的相互作用，在高磁场中的应用是有用的。该奖项支持凝聚态物理学和生物学之间的基础理论研究和教育。该研究集中在生物物理学，软凝聚态物质和II型超导体中的涡旋物理学问题上。前一个领域的工作包括研究病毒结构和随机势中运动的各种问题，这些问题的灵感来自于RNA链沿着DNA核苷酸序列的结合和运动的实验。 该奖项还支持研究生和更高级别的理论凝聚态物理培训，并倾向于与生物学接口的问题。这项工作的结果可能会对其他领域产生影响，特别是在分子和细胞生物科学领域。

0231631NelsonThis award supports fundamental theoretical research and education centered on problems in biophysics, soft condensed matter and the physics of vortices in Type II superconductors. The PI will study the architecture of virus shells in an effort to understand why small viruses are round and large ones are faceted. The faceting may be related to a buckling transition of the twelve 5-fold disclinations embedded in icosahedral arrays of protein capsomers. Theoretical advance could allow experimental determinations of elastic parameters from structural data. The PI will explore localization effects due to polynucleotide sequence variation on motor protein arrays such as RNA polymerases translating along a DNA strand. Sequential polymerization of single strand binding proteins such as Rec A and the maximum pull out force of DNA hybrids will be studied as well. In addition, problems in soft matter condensed matter physics will also be attacked, these include determining crystalline ground states on the torus and for colloids adsorbed onto negatively curved "plumber's nightmare" phases. Finally, work will continue on vortex matter in superconductors by exploring the unusual response (related to the transverse Meissner effect) of an entangled flux liquid with a dilute concentration of columnar pins to a tilted magnetic field. Methods will include analytical approaches to statistical mechanics and dynamics, numerical diagonalization of evolution operators and computer simulations of model systems inspired by problems in biology, soft condensed matter and vortex physics. Investigations of buckling in viral shells will exploit extensive experience with floating mesh discretizations of the nonlinear elastic equations which describe thin spherical shells. The PI will seek to benefit from close contact and vigorous interactions with the experimental community. This award supports graduate and higher level training in condensed matter theory. The work may also impact fields other than condensed matter physics. Understanding deformations of viral shells could identify weaknesses (such as ridgelines or grain boundaries) which would allow attack on harmful infectious agents. Explorations of how sequence randomness affects protein interactions with DNA and RNA might influence the design of artificial genetic circuits in bacteria. A comprehensive theory of defect arrays on curved surfaces could guide the construction of new materials with bicontinuous lipid phases as templates. Finally, understanding vortex interactions with columnar defects is useful for applications in high magnetic fields. %%%This award supports fundamental theoretical research and education at the interface between condensed matter physics and biology. The research is centered on problems in biophysics, soft condensed matter and the physics of vortices in Type II superconductors. The work in the former area includes the study of virus structures and various problems on motion in a random potential that are inspired by experiments on the binding and motion of RNA polymerize along a DNA nucleotide sequence. This award also supports graduate and higher level training in theoretical condensed matter physics with a bent toward problems at the interface with biology. The results of this work may have impact in other fields, notably in molecular and cellular biosciences.***