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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Archibald Hill | 1/3 | https://en.wikipedia.org/wiki/Archibald_Hill | reference | science, encyclopedia | 2026-05-05T17:34:32.491912+00:00 | kb-cron |
Archibald Vivian Hill (26 September 1886 – 3 June 1977), better known to friends and colleagues as A. V. Hill, was a British physiologist, one of the founders of the diverse disciplines of biophysics and operations research. He shared the 1922 Nobel Prize in Physiology or Medicine for his elucidation of the production of heat and mechanical work in muscles.
== Biography ==
=== Early life === Born in Bristol, the son of Jonathan Hill (1857–1924) and Ada Priscilla (née Rumney) (1861–1943), he was preceded on the paternal side by five generations of timber merchants at Bristol, carrying on the business which had been founded by James Hill in 1750. He was educated at Blundell's School and graduated from Trinity College, Cambridge as third wrangler in the mathematics tripos before turning to physiology. While still an undergraduate at Trinity College, he derived in 1909 what came to be known as the Langmuir equation. This is closely related to Michaelis–Menten kinetics. In this paper, Hill's first publication, he derived both the equilibrium form of the Langmuir equation, and also the exponential approach to equilibrium. The paper, written under the supervision of John Newport Langley, is a landmark in the history of receptor theory, because the context for the derivation was the binding of nicotine and curare to the "receptive substance" at the neuromuscular junction.
=== Hill equation === In 1910, Hill formulated the Hill equation, which is used to quantify binding of oxygen to haemoglobin, written here as a kinetic equation:
v
=
V
a
h
K
0.5
h
+
a
h
{\displaystyle v=V{\frac {a^{h}}{K_{0.5}^{h}+a^{h}}}}
Here
v
{\displaystyle v}
is the rate of reaction at concentration
a
{\displaystyle a}
of substrate,
V
{\displaystyle V}
is the rate at saturation,
K
0.5
{\displaystyle {K_{0.5}}}
is the value of
a
{\displaystyle a}
that gives
v
=
0.5
V
{\displaystyle v=0.5V}
, and the exponent
h
{\displaystyle h}
is a parameter that expresses the degree of departure from Michaelis–Menten kinetics: positive cooperativity for
h
>
1
{\displaystyle h>1}
, no cooperativity for
h
=
1
{\displaystyle h=1}
, and negative cooperativity for
h
<
1
{\displaystyle h<1}
. Note that there is no implication that
h
{\displaystyle h}
is an integer, and in most experimental cases, apart from the trivial case of
h
=
1
{\displaystyle h=1}
, it is not. Although many authors use
n
{\displaystyle n}
or
n
H
{\displaystyle {n_{\mathrm {H} }}}
rather than
h
{\displaystyle h}
these symbols are misleading if taken to imply that it shows the number of binding sites on the protein. Hill himself avoided any such interpretation. The equation can be rearranged as follows:
ln
[
v
/
(
V
−
v
)
]
=
h
ln
a
−
h
ln
K
0.5
{\displaystyle \ln[v/(V-v)]=h\ln a-h\ln K_{0.5}}
This shows that when the Hill equation is accurately obeyed a plot of
ln
[
v
/
(
V
−
v
)
]
{\displaystyle \ln[v/(V-v)]}
gives a straight line of slope
h
{\displaystyle h}
. This is called a Hill plot. In practice the line is usually not straight, and is curved at the extremes.
=== Family === In 1913, he married Margaret Neville Keynes (1885-1974), daughter of the economist John Neville Keynes, and sister of the economist John Maynard Keynes and the surgeon Geoffrey Keynes. They had two sons and two daughters:
Polly Hill (1914–2005), economist, married K.A.C. Humphreys, registrar of the West African Examinations Council. David Keynes Hill (1915–2002), physiologist, married Stella Mary Humphrey Maurice Hill (1919–1966), oceanographer, married Philippa Pass Janet Hill (1918–2000) child psychiatrist, married the immunologist John Herbert Humphrey.
=== World War I service === While a student, he enrolled in the Officers Training Corps as a crack shot. In 1914, at the outbreak of the First World War, Hill became the musketry officer of the Cambridgeshire Regiment. At the end of 1915, while home on leave he was asked by Horace Darwin from the Ministry of Munitions to come for a day to advise them on how to train anti-aircraft gunners. On site, Hill immediately proposed a simple two mirror method to determine airplanes' heights. Transferred to Munitions, he realized that the mirrors could measure where smoke shells burst and if he fitted this data with the equations describing a shell's flight they could provide accurate range tables for anti-aircraft guns. To measure and compute he assembled the Anti-Aircraft Experimental Section, a team of men too old for conscription, Ralph H. Fowler (a wounded officer), and lads too young for service including Douglas Hartree, Arthur Milne and James Crowther. Someone dubbed his motley group "Hill's Brigands", which they proudly adopted. Later in the war they also worked on locating enemy planes from their sound. He sped between their working sites on his beloved motorcycle. At the end of the war, Major Hill issued certificates to more than one hundred Brigands. He was appointed an Officer of the Order of the British Empire (OBE).