User manual

278
APPENDIX D Serious Bugs in Previous Versions that have been
Fixed
D.1 Bug in Changing Detection Parameter Fields which could
previously cause a program Hang=Up (in WinLTP 2.10)
1. We have done extensive debugging of Changing Detection Parameter Fields which, in previous
versions, could, on rare occasions, lead to a program hang-up.
D.2 Bug fixed in Rs/Rm Measurement due to faulty use of RsRm
pulse amplitude (in WinLTP 0.96)
1. When a protocol file is loaded, the RsRm pulse amplitude is the one used CORRECTLY for Rs and Rm
calculations.
2. Therefore, if you don’t change your RsRm pulse amplitude during experiments, only the first
experiment after a new protocol file has been written may have incorrect Rs and Rm values. The rest of
the experiments will be fine.
3. However, if this RsRm pulse amplitude is changed during the experiment, the original RsRm amplitude
is INCORRECTLY still used for all Rs and Rm calculations in this experiment. This will result in Rs and
Rm being both incorrect and even negative for this one experiment.
D.3 Corrected cell input resistance measurement Rm (in WinLTP
0.94)
In the previous versions of WinLTP from WinLTP 0.90 to WinLTP 0.93, the cell input resistance Rm was
incorrectly calculated as
Rm = V
Pulse
/ I
SteadyState
and is now correctly calculated in WinLTP 0.94 and later as
Rm = V
Pulse
/ I
SteadyState
- Rs
where V
Pulse
is the amplitude of the RsRm voltage clamp test pulse, I
SteadyState
is the amplitude of the
current measured between the baseline and 70% and 90% of the pulse when the current has reached
steady state, and Rs is the patch electrode series resistance.
Because Rs is usually much less than Rm, Rm ~ Vpulse / Isteadstate still is roughly true, but since Rs
values are typically 5% to 10% of Rm values, previous Rm values (from WinLTP 0.90 to WinLTP 0.93)