Breed and Dotterrer published a seminal paper on this topic in 1916 (2). The origin of those ranges is worth examination. The general ranges in common acceptance for countable numbers of colonies on a plate are 30 – 300 and 25 – 250. While you might get lucky and hit this with dilutions whose plate counts are in the 150-250 CFU/plate range, – at lower plate counts this target value imposed by regulation will virtually guarantee a long, difficult and quite possibly unsuccessful, validation exercise. A good example of this is the Pharm Eur “Precision” requirement for an alternate method (quantification) to have a Relative Standard Deviation (RSD) in the range of 10-15% (1). Being obsessive by training, we are trying to exceed measures of accuracy and precision in this exercise that the traditional methods cannot come close to matching. We have allowed specifications for environmental monitoring, raw material bioburden, in-process bioburden and finished product bioburden to be imposed by regulation without regard for the ability of the method to support those specifications.Ī second reason for concern is that now we are trying to introduce alternate microbiological methods into the lab. Our lax attention to precision and accuracy in our measurements helps further this perception. One reason for concern is that microbiology has a well-deserved reputation for being highly variable. A colony could arise from one cell, or several thousand. Even among that group of microorganisms a colony does not represent a single cell, but rather cells that happened to be well separated on the plate and so can be distinguished after growth. It is a skewed estimate at best as the only cells able to form colonies are those that can grow under the conditions of the test (incubation media, temperature, time, oxygen conditions, etc). What is the fuss about in determining the number of colony forming units? After all, the CFU is only an estimate of the number of cells present. I'll put in a "back to main menu" in the bad ends.This article first appeared in the PMF Newsletter of January, 2006 and is protected by copyright to PMF. I did have a restart button, but kind of removed it as it was just redundant in many ways. Earth in the game is supposed to be relatively crime free and, now, resource rich, so there wasn't much room for expansion as I want to keep the game consistent. I also could have added a ton more content in with this release, however, I decided not to "blow my load" as it makes sense narratively that later in the game the more seedy elements of human society come into play. I do plan for some playable bad ends with repeatable fail states. A lot of the content is going to be bad ends, as mentioned, it is primarily inspired by the older RAG games like RL, Tales and Lilith Device - I like interesting bad ends for the character. Ceres, as a hub, is planned to be the largest part of the game with five or six different areas all accessible at once. The next chapter, however, will be unique as it'll be three different scenarios that'll take you through three different parts of the station, though at the price it'll be more linear (there is a reason for this, story wise). For the most part, the game will follow the same path despite the route you pick, but you'll have different methods of solving problems and have access to different. Click to expand.Thanks for the feedback, that is what I'm going for.
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