A critical time constant for exponential heating is identified such that the strength of the wave is equivalent to that for an instantaneous step in wall temperature.
A range of functions associated with cAMP and protein kinase A signaling came up in the exponential heat-shock screen, including Ira1p (GTPase-activating protein that negatively regulates RAS), Cyr1p (adenylate cyclase), Cdc25p (guanine nucleotide exchange factor that regulates adenylate cyclase through activation of Ras1p and Ras2p), and Tpk1p (one of three protein kinase A catalytic subunits).
However 25 thermosensitive mutants did show a significant overlap (P = 6 × 10−6) with the exponential phase heat-shock sensitive mutants indicating that there are some functions in common between thermotolerance and heat-shock resistance during exponential growth.
For analysis of exponential phase heat-shock survival for essential genes, strains were inoculated from stationary phase YEPD cultures into 150 μL of fresh YEPD medium liquid, grown for 17 hr and subjected to heat shock as per the methodology outlined for non-essential genes.
An explosion is simply an exponential rise in heat.
(Exponents are explosive. A bomb detonation is only an exponential gain in heat).
This was explained by an exponential decrease of heat production with depth over a crustal scale.
To this end, we utilize an exponential model of heat generation versus depth: H z) = H_{0} e^{{left( {frac{ - z}{D}} right)}} (3)where (H_{0}) and (H z)) denote the radiogenic heat generation at the surface and at a particular depth, respectively.
For sequencing the whole transcriptome we used RNA samples from nine different conditions (exponential growth phase, heat and cold shock, salt stress, oxidative stresses, and ethanol stress) to obtain a broad range of transcripts.
Therefore we tested the ability of the sigS mutant to grow at elevated temperatures (40°C and 45°C), and to survive heat shock (exponential cultures placed at 55°C for 15 mins before being returned to growth at standard conditions).
The exponential increase of the heat signal reflects the exponential increase in bacterial numbers during the logarithmic growth phase [ 17].
