These are my recent Pinboard.in links:
-
A Way To Think About Online Courses (By Apple, For Example) | Easily Distracted
"One thing that struck me during the meeting, though, was that if you created a really rich body of materials that looked somewhat like an “online course”, what you really might be doing was crafting a completely novel form of publication. Imagine a work of historical scholarship that included video of the author giving an explanatory lecture at the beginning of a section of the reading; that had direct links to a huge body of archival pictures, audio recordings, maps, and other supporting materials; that extensively linked to relevant (or competing) analyses available in digital collections like JSTOR; and where the author would appear live once every week to take questions from students reading the book in a class."
media academic-culture pedagogy publishing a-new-tent-and-a-new-camel
-
Evolution of increased complexity in a molecular machine : Nature : Nature Publishing Group
"Many cellular processes are carried out by molecular ‘machines’—assemblies of multiple differentiated proteins that physically interact to execute biological functions1, 2, 3, 4, 5, 6, 7, 8. Despite much speculation, strong evidence of the mechanisms by which these assemblies evolved is lacking. Here we use ancestral gene resurrection9, 10, 11 and manipulative genetic experiments to determine how the complexity of an essential molecular machine—the hexameric transmembrane ring of the eukaryotic V-ATPase proton pump—increased hundreds of millions of years ago. We show that the ring of Fungi, which is composed of three paralogous proteins, evolved from a more ancient two-paralogue complex because of a gene duplication that was followed by loss in each daughter copy of specific interfaces by which it interacts with other ring proteins. These losses were complementary, so both copies became obligate components with restricted spatial roles in the complex. Reintroducing a single historical mutation from each paralogue lineage into the resurrected ancestral proteins is sufficient to recapitulate their asymmetric degeneration and trigger the requirement for the more elaborate three-component ring. Our experiments show that increased complexity in an essential molecular machine evolved because of simple, high-probability evolutionary processes, without the apparent evolution of novel functions. They point to a plausible mechanism for the evolution of complexity in other multi-paralogue protein complexes."
via:cshalizi evolution structural-biology parsimony dangers-of-premature-optimization lesson-for-genetic-programming