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   https://doi.org/10.1175/JAS-D-20-0388.1  

   Thomas, Subin; Prabhakaran, Prasanth; Cantrell, Will; Shaw, Raymond A. (May 2021, Journal of the Atmospheric Sciences)

   Abstract Water vapor supersaturation in the atmosphere is produced in a variety of ways, including the lifting of a parcel or via isobaric mixing of parcels. However, irrespective of the mechanism of production, the water vapor supersaturation in the atmosphere has typically been modeled as a Gaussian distribution. In the current theoretical and numerical study, the nature of supersaturation produced by mixing processes is explored. The results from large eddy simulation and a Gaussian mixing model reveal the distribution of supersaturations produced by mixing to be negatively skewed. Further, the causes of skewness are explored using large eddy simulations (LES) and the Gaussian mixing model (GMM). The correlation in forcing of temperature and water vapor fields is recognized as playing a key role. 

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2. Water and Life: The Medium is the Message

   https://doi.org/10.1007/s00239-020-09978-6  

   Frenkel-Pinter, Moran; Rajaei, Vahab; Glass, Jennifer B.; Hud, Nicholas V.; Williams, Loren Dean (February 2021, Journal of Molecular Evolution)

   Abstract Water, the most abundant compound on the surface of the Earth and probably in the universe, is the medium of biology, but is much more than that. Water is the most frequent actor in the chemistry of metabolism. Our quantitation here reveals that water accounts for 99.4% of metabolites in Escherichia coli by molar concentration. Between a third and a half of known biochemical reactions involve consumption or production of water. We calculated the chemical flux of water and observed that in the life of a cell, a given water molecule frequently and repeatedly serves as a reaction substrate, intermediate, cofactor, and product. Our results show that as an E. coli cell replicates in the presence of molecular oxygen, an average in vivo water molecule is chemically transformed or is mechanistically involved in catalysis ~ 3.7 times. We conclude that, for biological water, there is no distinction between medium and chemical participant. Chemical transformations of water provide a basis for understanding not only extant biochemistry, but the origins of life. Because the chemistry of water dominates metabolism and also drives biological synthesis and degradation, it seems likely that metabolism co-evolved with biopolymers, which helps to reconcile polymer-first versus metabolism-first theories for the origins of life. 

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3. Is water shortage risk decreased at the expense of deteriorating water quality in a large water supply reservoir?

   https://doi.org/10.1016/j.watres.2019.114984  

   Xu, Zhihao; Cai, Ximing; Yin, Xinan; Su, Meirong; Wu, Yiping; Yang, Zhifeng (November 2019, Water Research)
4. Peptide Isomerization is Suppressed at the Air–Water Interface

   https://doi.org/10.1021/acs.jpclett.1c03837  

   Singh, Aditya N.; Limmer, David T. (January 2022, The Journal of Physical Chemistry Letters)
5. Water-directed pinning is key to tau prion formation

   https://doi.org/10.1073/pnas.2421391122  

   Vigers, Michael P; Lobo, Samuel; Najafi, Saeed; Dubose, Austin; Tsay, Karen; Ganguly, Pritam; Longhini, Andrew P; Jin, Yingying; Buratto, Steven K; Kosik, Kenneth S; et al (May 2025, Proceedings of the National Academy of Sciences)

   Tau forms fibrillar aggregates that are pathological hallmarks of a family of neurodegenerative diseases known as tauopathies. The synthetic replication of disease-specific fibril structures is a critical gap for developing diagnostic and therapeutic tools. This study debuts a strategy of identifying a critical and minimal folding motif in fibrils characteristic of tauopathies and generating seeding-competent fibrils from the isolated tau peptides. The 19-residue jR2R3 peptide (295 to 313) which spans the R2/R3 splice junction of tau, and includes the P301L mutation, is one such peptide that forms prion-competent fibrils. This tau fragment contains the hydrophobic VQIVYK hexapeptide that is part of the core of all known pathological tau fibril structures and an intramolecular counterstrand that stabilizes the strand–loop–strand (SLS) motif observed in 4R tauopathy fibrils. This study shows that P301L exhibits a duality of effects: it lowers the barrier for the peptide to adopt aggregation-prone conformations and enhances the local structuring of water around the mutation site to facilitate site-directed pinning and dewetting around sites 300-301 to achieve in-register stacking of tau to cross β-sheets. We solved a 3 Å cryo-EM structure of jR2R3-P301L fibrils in which each protofilament layer contains two jR2R3-P301L copies, of which one adopts a SLS fold found in 4R tauopathies and the other wraps around the SLS fold to stabilize it, reminiscent of the three- and fourfold structures observed in 4R tauopathies. These jR2R3-P301L fibrils are competent to template full-length 4R tau in a prion-like manner. 

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