Articles to 2019-12-08

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First the link to this week's complete list as HTML and as PDF.


At first glance I took Callaway and then Erb et al. and Gleizer et al. to be a hoax, a scam or rather a fallback into Medieval superstition, Wundererzählungen und Heiligenlegenden. They aren't, not quite. They use engineered bacteria in a process that produces and releases far more carbon dioxide than it consumes, although they seem to be honest: all the carbon used in building all the biomass comes from extracted gaseous carbon dioxide. So what is it about?

As they say “Yet, in future coupling to a renewable energy source, formate would be produced electrochemically from CO2 with negative greenhouse gas emissions. Formate could then be used as the feedstock for biotechnological production of various chemicals using the synthetically autotrophic E. coli as the bioproduction platform.” Of course bacteria are quite superior to chemical synthesis in producing complicated things like insulin. But wouldn't it be preferable and easier to feed efficient bacteria some sugar and use the expensive synthetic formate in other, better ways?

Gleizer et al. even tell us what it really is that they have been doing. “This study is, therefore, a stepping stone to future efforts seeking to understand evolutionary transitions and harnessing synthetic biology on the path to more sustainable bioproduction.” All valuable and very worth-while stuff. The problem is to get it funded. So why not glean subsidies from stupid uneducated career politicians who never read past the headlines and are stumped by a simple energy and mass balance? Why not indeed, except that it's my taxes they're throwing about. Admittedly this is one of the least silly show projects they're squandering them on.


Palmer & Stevens say more or less the same things I frequently allude to here. No doubt they are far less critical than I am, but they also explain why critical readers like me have good reasons not to trust everything we're told on sight.


From the title I had high expectations in Han et al.'s study. Unfortunately it turned out to be entirely meaningless. The point about lean mixtures is, that power density becomes low and quenching distance high. They are extremely hard to ignite with conventional plugs, as the tiny plug gaps and large and blunt electrodes quench the incipient flame and prevent it from spreading. Their plug's sharp and much smaller electrodes alone are totally sufficient to explain all of their result. The triple spark and spread timing may add a tiny bit extra, but to demonstrate that it would need to be compared to one with equally good and not vastly inferior electrode arrangement.

It’s a shame really. Improved ignition is a vastly under utilised course of improvement. At least my daughter's Japanese car comes with a spark gap of 1.1 mm – nearly approaching the state of the art of the 1920ies.


I consider James C. Scott's Against the Grain a fantastic book, one I love to give away to discerning friends. Thus I read its dissemination by a group of distinguished scholars with great interest. In the main they mostly agreed with my appreciation.

Where they disagreed it was mostly from the humanities' unease with simplifying and generalising models. These humanists would be utterly shocked if they learnt that in describing vehicle dynamics physicists not only lump together Formula One racing cars, cheap family saloons, and forty-ton lorries as one and the same and even reduce them to an unstructured, formless point mass, but also yield results that ignore their single remaining property and come up with forces that are all in fixed proportion to the ground force irrespective of mass. They recklessly throw away all the wonderful fine detail of engineering that goes into a road-hugging sports car. What the humanists with their love for detail and individuality consistently overlook is, that it is only against this canvas of a common imposed background that you can meaningfully describe individual cultures and all their wonderful idiosyncrasies, without it all this richness of unique features would become no more than a meaningless jumble.

A premier example of what simple modelling can do is provided by Turchin (lists of 2013-10-14 and 2018-01-15). As I said then: “Besides their surprisingly convincing success the result also points out those cultural aspects and world regions, where their prediction is least successful. These are the places cultural anthropologists can fruitfully look into without wasting their resources on areas that culture has little meaningful influence on.”

On the whole after reading these reviews I as a non specialist feel fully justified to continue giving this book to other non specialists.

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