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Integral curve estimation is a well-established method for reconstructing in vivo nerve fiber pathways in thewhite matter of the brain. Using longitudinal high angular resolution diffusion imaging (HARDI) data, weformulate the longitudinal ensemble of fiber trajectories as an integral curve with the parameter time. The goalof this article is to develop a test statistic to determine whether there are anatomically plausible changes innerve fibers with two directions, such as crossing, kissing, or bending fibers. We envision that rejecting thenull hypothesis could help identify a potential anatomical biomarker for neurodegenerative diseases, such asAlzheimer’s disease.
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Discrimination of RNA fiber structures using solid-state nanopores
RNA fibers are a class of biomaterials that can be assembled using HIV-like kissing loop interactions. Because of the programmability of molecular design and low immunorecognition, these structures present an interesting opportunity to solve problems in nanobiotechnology and synthetic biology. However, the experimental tools to fully characterize and discriminate among different fiber structures in solution are limited. Herein, we utilize solid-state nanopore experiments and Brownian dynamics simulations to characterize and distinguish several RNA fiber structures that differ in their degrees of branching. We found that, regardless of the electrolyte type and concentration, fiber structures that have more branches produce longer and deeper ionic current blockades in comparison to the unbranched fibers. Experiments carried out at temperatures ranging from 20–60 °C revealed almost identical distributions of current blockade amplitudes, suggesting that the kissing loop interactions in fibers are resistant to heating within this range.
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- Award ID(s):
- 1827346
- PAR ID:
- 10387691
- Date Published:
- Journal Name:
- Nanoscale
- Volume:
- 14
- Issue:
- 18
- ISSN:
- 2040-3364
- Page Range / eLocation ID:
- 6866 to 6875
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d1nr08002d
