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OPINION Reactions ShareShare onFacebookTwitterWechatLinked InRedditEmail C&EN, 2018, 96 (45), p 2November 12, 2018Cite this:C&EN 96, 45, 2Liquid from water I enjoyed very much the article on water-from-air technologies (C&EN, Oct. 15, page 26), but perhaps it might have discussed the inherent energy differences between liquid water from fog and liquid water from water vapor. Of course liquid from vapor involves the heat of vaporization (condensation), which warms the condensing medium and must be removed and, hopefully, put to use elsewhere in the system. Liquid water from fog is different. Here, condensation has already occurred, and the inherent energy difference is the change in surface area times the surface tension, far less than the heat of vaporization (condensation).For those with time on their hands, it is fun to calculate, on the basis of change in surface area times surface tension, the energy required to reduce a liter of water to molecular-sized water bits. This is somewhat absurd, as there is no real surface tension or surface area of a small handful of water molecules, but one still ends up with something surprisingly close to the heat of vaporization (which is as it should be).Jim Birkett Nobleboro, Maine Corrections Oct. 29, page 29: The cover story about drug development for endometriosis incorrectly described the mechanism of action of the AbbVie treatment Lupron Depot. It is a gonadotropin-releasing hormone agonist, not antagonist.Nov. 5, page 6: A news story about spiky nanoparticles had the incorrect scale bar on an image of those nanoparticles. It should be 1 μm rather than 400 mm.Nov. 5, page 13: Because of a production error, the end of an article about a drug development agreement between Sanofi and Denali Therapeutics was cut off. Starting from the last sentence, it should read: “Yuan found that in addition to unprogrammed apoptosis, cells undergo programmed death via the TNF pathway, which is in part mediated by RIPK1.“Her group later developed a small-molecule inhibitor of the enzyme. Denali discontinued a Phase I study of Yuan’s molecule, DNL104, because of liver toxicity, Schuth says, but its scientists went on to develop DNL747 and DNL758, which was designed for systemic use.”.