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- Reseed/New: Type 'N' or 'R' to begin a new simulation or continue a
- previous run. If you choose the reseed option you must have a file
- available containing the saved data from a previous run and you will be
- prompted for the path and name of that file. When you continue a
- previous run you will have only limited options for changing the
- original settings established when that run was inititated.
- Stagnant/Circulating: Type 'S' or 'C' to choose between a
- non-circulating, 'pond' type simulation and a circulating mode
- comparable to a stirred flask. In the stagnant mode, conditions may
- differ from top to bottom of the simulation. In the circulating mode,
- conditions will be homogenous except for light intensity (light is
- absorbed by the 'medium', hence is at its highest intensity at the top
- of the simulation).
- Open/Closed: Type 'O' or 'C' to choose between having the head space
- gases in equilibrium with a selected atmospheric value or having the
- simulation 'sealed' from the outside world.
- Random/Defined: Type 'R' or 'D'. The Random choice will cause the
- simulation to be initiated with organisms of random genetic
- composition. The Defined option allows you to enter up to 3 genomes of
- your choice or will allow seeding with a collection of known genomes.
- Inhibitors: Twelve 'substances', letter names A to L, are available
- which act as 'biochemical inhibitors'. These can be added in
- combinations of up to six at one time to investigate the various
- simulated chemical pathways that may be available within any given
- collection of organisms. To enter an inhibitor type the appropriate
- letter.
- Mutagen: Analagous to a mutagenic factor, such as UV radiation, in
- natural environments. Mutagen controls the rate at which 'mutations'
- occur in the simulated genome. A value of 0 results in no mutations
- and is useful for studying the characteristics of defined populations.
- Light intensity: Luminance at the surface of the simulation. The value
- assumes that portion of the spectrum which is photosynthetically
- active. A value of 0 represents darkness.
- Depth: Effective only in the stagnant model, this variable determines
- the rate at which solutes diffuse vertically in the simulation.
- Horizontal distribution is considered to be homogeneous. Higher values
- are equivalent to a deeper pond.
- Oxygen: Sets the concentration of oxygen in the aqueous phase in
- equilibrium with the gas phase in open systems. Also provides the
- initial concentration of oxygen at the start of a new simulation
- whether open or closed.
- Carbon dioxide: Sets the concentration of carbon dioxide in the
- aqueous phase in equilibrium with the gas phase in open systems. Also
- provides the initial concentration of carbon dioxide at the start of a
- new simulation whether open or closed.
- Reservoir size: A technical factor that determines the relative
- effect of metabolism of each organism on the substrate pool. It is
- analagous to buffering capacity in a natural medium and is loosely
- analagous to the volume of a natural system. A low value produces a
- simulation in which substrate becomes limiting at low population
- densities.
- Starting population: The number of 'organisms' with which the
- simulation is initially seeded. Not meaningful in reseed and seeding
- options.
- Soluble substrate concentration: The concentration of soluble organic
- matter in the simulation at startup.
- Amount sediment: The total mass of sediment at the start of the
- simulation. Some sediment may be suspended in the aqueous phase and
- some may be trapped at the bottom of the simulation. The sediment
- serves as substrate for some biochemical pathways.
- Number of genomes: Allows selecting up to 3 predefined genomes when the
- defined option was previously chosen. The configuration for each
- genome will be entered on a following input screen. This option also
- permits entering the letter 'S' to indicate seeding from a previous
- run. The seed option differs significantly from reseeding in that all
- the input variables can be reselected. It is analagous to adding a
- drop of old culture to a new batch as compared to simply continuing the
- incubation of the old batch.
- This screen appears only when the defined option was previously
- selected and 1, 2, or 3 genomes was entered. To enter a known genome,
- type over the default or old genome using the letters 'E', 'F', 'G', or
- 'H' (upper or lower case is acceptable). The boxes on the right hand
- side contain the percentage of each genome which will be represented in
- the final population. When only one genome is entered this box is
- always set at 100. In all other cases the total of all boxes (2 or 3)
- must add to 100. An attempt to enter a value of more or less than 100
- will not be accepted.