nat as
in which z is a single energy deposition
the
(TCV) of
-yputtous
the cell,
t.e.,
hit and exposed cells,
number of
the “cell dose";
respectively,
in
the
Ny and Np are
and F is
receiving an energy deposit during exposure E,
tion
target-containing volume
the
the number of
probability of 4 cell TCV
equal numerically
to
Ny/ Np
shaped
However,
tt is well known from physics
thac,
oilp
onse 45 4
F = Or
iLtiplied by
= 27,
(2)
c
r
quanticative
in which 0 is the field strength measured as fluence race (units of
ced endpolntss
particles em72 tt), which expresses
sure enat wiht
energy-conveying charged particles;
tp is
the expnsure
time;
4 is
fluence to which the total exposure is numerically equal; and
ally is much
“cross section”, or constant of proportionality.
simply
@
to the
the
is the
Thus, substituting in
Eq. (1), from Eq. (2),
isk tiwt 4
D
also, with
ntal
= 207,
(3)
in which z = k because, with stochastic energy deposition, and LLE, the
expectation value of
the mean cell dose is invariant with exposure.
Eq. (1) confirms that stated above, namely that D to the organ system
ze been put
at of
the rate of exposure (of cells)
ts not a dose to the cell, and that {ts equivalent is required for the
the
level of Diological organization, the cell, that is appropriate to the
“late single-cell initiated effects” of LLE, mutagenesis and
carcinogenesis.
ements »
it is
sorbed dose tO:
syste.
This
population,
D conceptually becomes the exposure of the cell
to which Ry/Ne is proportional,
that is to say,
“object-orlented quantity” Nase, as seen in Eq. (3), is proportional
to
the primary independent “field-oriented” varlable the exposure E, for
which 6 can be used as a parameter.
|
With D becoming $ conceptually, a rational basis
-\
--
Sy
Je
E
sT*,
the
“linear-non-threshold” relationship is provided.
for tie
Although frou
toxicvlogical priaciples a purported linear relationship between dose and
the probability of a quantal response tends
to defy credulity,
such a
relationship between exposure E and the number of (stochastically) dosed
individuals, or of those showing a quantal response is quite reasonable.
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