September 17, 2016 at 04:41AM

Today I Learned: 1) Two transcriptional elongation factors called GreA and Greb are very, very important for efficient transcription in E.-coli-based* transcriptional systems. Addition of GreA and GreB to a minimal in vitro transcription/translation system (PURE express) increased yield about 6-fold, which brings them much, much closer to the kinds of yields we regularly get out of TX-TL. * anyone have a better way to punctuate this? 2) When you assign a computer a new IP address, you may need to release and refresh that computer's IP configuration, which can be done by running ipconfig \release ipconfig \refresh 3) ...a bit about how stocks and public companies work. As I gather, the basic idea of stocks is that it's a way for a company to make a ton of money by selling itself to lots of shareholders who want to invest in a company without shelling out tons of money or getting directly involved with the company in any kind of deep way. When a company "goes public" (which basically means it signs up on some kind of public trading list and legally commits to making a bunch of its financial information public), it gains the ability to sell stocks to whoever wants to buy them. This is great for the company, because it gives them a huge influx of instant cash. It's even better for early investors, because they typically get paid back during the going-public event. Stocks nominally derive their value either from dividends that the stock pays (which are typically single-digit-per-year returns) or from the ability of a stock-owner to vote in certain decisions of the company with a weight proportional to the number of stocks the stock owner owns. In practice, I'm fairly confident that stocks are more like currency than a good -- they have value because everyone believes they have value. Companies can decide to create and sell more stock whenever they want to. When that happens, it can be really bad for investors who already own stock, because a) they suddenly own far less of the controlling share of the company and b) the supply of stock goes up drastically (which I suspect is the bigger effect). However, it can also be really good for investors, because selling stock gives the company a ton of money to work with, which can put them way ahead in the marketplace, which can make their stocks more valuable again. So it's an intricate balance. Another thing companies can do is *split* their stocks, which means they basically declare that everyone who owns stock now owns, say, twice as many stocks with half the value each (or, in general, X times as many stocks with 1/X times the value each). This is apparently really annoying for stockholders, although I don't really know why, but it's nice for the company because it lowers the barrier to purchase a single stock. Google once promised that they would never split their stocks, but they did when their stock reached something like $1000/stock. Warren Buffet also once promised that he would never split his stocks for Berkshire Hathaway, and he has held true to his word -- as of tonight, those stocks go for $218,400 apiece. Thanks to Kevin Cherry for graciously imparting some of his knowledge of stocks and stock trading!