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Persistent Homology (PH) is a method of Topological Data Analysis that analyzes the topological structure of data to help data scientists infer relationships in the data to assist in informed decision- making. A significant component in the computation of PH is the construction and use of a complex that represents the topological structure of the data. Some complex types are fast to construct but space inefficient whereas others are costly to construct and space efficient. Unfortunately, existing complex types are not both fast to construct and compact. This paper works to increase the scope of PH to support the computation of low dimensional homologies (H0 –H10 ) in high-dimension, big data. In particular, this paper exploits the desirable properties of the Vietoris–Rips Complex (VR-Complex) and the Delaunay Complex in order to construct a sparsified complex. The VR-Complex uses a distance matrix to quickly generate a complex up to the desired homology dimension. In contrast, the Delaunay Complex works at the dimensionality of the data to generate a sparsified complex. While construction of the VR-Complex is fast, its size grows exponentially by the size and dimension of the data set; in contrast, the Delaunay complex is significantly smaller for any given data dimension. However, its construction requires the computation of a Delaunay Triangulation that has high computational complexity. As a result, it is difficult to construct a Delaunay Complex for data in dimensions d > 6 that contains more than a few hundred points. The techniques in this paper enable the computation of topological preserving sparsification of k-Simplices (where k ≪ d) to quickly generate a reduced sparsified complex sufficient to compute homologies up to k-subspace, irrespective of the data dimensionality d.
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This content will become publicly available on October 21, 2026
Cooperative enhancement of redox catalysis in divanadium complexes binucleated by 1,8-naphthyridine-2,7-dicarboxylate
We report discrete divanadium complexes of 1,8-naphthyridine-2,7-dicarboxylate, characterized by SCXRD, DFT modelling, and magnetometry. One complex shows significantly greater activity in the aerobic cleavage of diols and a lignin model compound than its monometallic analogs. Mechanistic experiments and a substrate-bound complex provide insight into cooperativity in vanadium redox catalysis.
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- Award ID(s):
- 2337696
- PAR ID:
- 10648342
- Publisher / Repository:
- The Royal Society of Chemistry
- Date Published:
- Journal Name:
- Dalton Transactions
- Volume:
- 54
- Issue:
- 41
- ISSN:
- 1477-9226
- Page Range / eLocation ID:
- 15400 to 15405
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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