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A<sc>bstract</sc> We describe the projective superspace approach to supersymmetric models with off-shell (0, 4) supersymmetry in two dimensions. In addition to the usual superspace coordinates, projective superspace has extra bosonic variables — one doublet for each SU(2) in the R-symmetry SU(2) × SU(2) which are interpreted as homogeneous coordinates onCP1×CP1. The superfields are analytic in theCP1coordinates and this analyticity plays an important role in our description. For instance, it leads to stringent constraints on the interactions one can write down for a given superfield content of the model. As an example, we describe in projective superspace Witten’s ADHM sigma model — a linear sigma model with non-derivative interactions whose target isR4with a Yang-Mills instanton solution. The hyperkähler nature of target space and the twistor description of instantons by Ward, and Atiyah, Hitchin, Drinfeld and Manin are natural outputs of our construction.
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A Chemiluminescent Probe for HNO Quantification and Real‐Time Monitoring in Living Cells
Abstract Azanone (HNO) is a reactive nitrogen species with pronounced biological activity and high therapeutic potential for cardiovascular dysfunction. A critical barrier to understanding the biology of HNO and furthering clinical development is the quantification and real‐time monitoring of its delivery in living systems. Herein, we describe the design and synthesis of the first chemiluminescent probe for HNO,HNOCL‐1, which can detect HNO generated from concentrations of Angeli's salt as low as 138 nmwith high selectivity based on the reaction with a phosphine group to form a self‐cleavable azaylide intermediate. We have capitalized on this high sensitivity to develop a generalizable kinetics‐based approach, which provides real‐time quantitative measurements of HNO concentration at the picomolar level.HNOCL‐1can monitor dynamics of HNO delivery in living cells and tissues, demonstrating the versatility of this method for tracking HNO in living systems.
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- Award ID(s):
- 1653474
- PAR ID:
- 10082037
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 58
- Issue:
- 5
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 1361-1365
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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