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Activity

Activity

1. The state of being active, the ability to produce some effect, the extent of some function or action.

2. (Science: chemistry) a thermodynamic quantity that represents the effective concentration of a solute in a nonideal solution, if concentrations are replaced by activities, the equations for equilibrium constants, electrode potentials, osmotic pressure, boiling point elevation, freezing point depression and vapour pressures of volatile solutes are converted from approximations that hold only for dilute solutions to exact equations that hold for all concentrations. The activity is equal to the product of the concentration and the activity coefficient, a dimensionless number measuring deviation from nonideality. Symbol a.

The potential or true thermodynamic activity of a substance, as opposed to its molar concentration.

3. (Science: radiobiology) The number of nuclear transitions or disintegrations occurring in a given quantity of radioactive material per unit time. The si unit of activity is s-1. The special name for the unit of activity is becquerel (bq). The previously used special unit of activity, curie (ci), is being replaced by the becquerel. 1 bq = 2.7 x E-1 3a5 1 ci. 1 ci = 3.7 x E10 bq.

4. Optical activity.


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principle of error-prone PCR???

... affect the Taq enzyme? Did they changes the fourth-level structure of the Taq enzyme, such as combine with the regulatory subunit to control the activity, or something else. I mean, it is obviously not the charges, Mn2+ ions carry two positive as well as magesium; plus, Mn2+ ions have exactly ...

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by feixiaorou
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Re: Any ideas for vaccine development or anti-viral drugs???

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... increase in the expression by Western blot and we could conclude that the particular transcription factor is more active... do TFs need activity assays to be validated?

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licorice root a stress reliever?

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Wed Mar 12, 2014 11:09 pm
 
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Re:

... sense to me. Strong emotions are immediate, accompanied by an adrenalin rush. Think of horror films. In every field there is easy work/activity and difficult work/activity. In mathematics there is easy mathematics and difficult mathematics. Everyone can add 2+4 within microseconds. ...

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Sat Mar 08, 2014 4:20 am
 
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