Peli sling tani

staal oa edo aes

HEMISTS describe all substanc

Some common elements are aluminum, c
t 100 elements, 96 of which have actually been

of matter, called elements.

Present-day theory indicates the existence of abou

demonstrated to date.

The smallest single part of any
element which may be thought
of as showing the chemical pro-

) perties characteristic of that
element is called an atom. Since
there are demonstrably 96 dif-
ferent sorts of elements, there
are consequently 96 different
sorts of atoms.

At first it was believed that all
atoms of a given element were
exactly alike, but investigation
revealed they may differ in weight

and also in stability. An atom

lacking in stability is one which
emits penetrating rays some-
what similar in their effect to
the radiation produced by an
X-ray tube When atoms of an
element differ from each other
they are known as isotopes. if
the isotopes emit radiation, they
are specified as radioisotopes, and
are said to be radioactive.

For example, five isotopes of
the element carbon are known.
They differ from each other in
weight, having atomic weights
of approximately 10, U1, 12, 13
and 14 units, respectively. Car-
bons 12 and 13 are stable. Carr
bons 10, 11 and 14 are unstable—
they emit radiation and are there-
fore radioisotopes of carbon:

The radiations emitted from
radioactive isotopes have the
power to produce changes in
living matter, and even to disrupt
and destroy living cells. For this
reason they may be employed in
medicine to destroy undesirable

and dangerous growths — such

as some kinds of cancers—and x0
help in the removal ‘of certain
unsightly birthmarks.

The radiations from isotopes

also provide a method of identi-

fying the number and location of

"the radioactive atoms in any body

‘tissue. This is done by detecting
and counting the rays by means

of special instruments developed —

for this purpose.

One of these is the Geiger coun-
ter, anothen the Lauritsen electro-
scope, and a third the *scintilla-
tion counter. Photographic film
may also be used as a detector,
for exposure to the rays will cause

dark spots to appear on the film |

after development.

e

This ability of radioisotopes to
signal their presence is some-
times of value medically in deter-
mining the position and size of
tumors. :

For exaniple, the thyroid gland,
normally in the throat, removes
iodine from the blood stream very
readily. Occasionally this gland
may be abnormally located, pos-
sibly at the base of the tongue or
under the breast bone; multiple
cancerous thyroid growths may

e in terms of various combinations of fundamentally different types

carbon, iron and_ sulphur.

be present in unknown locations,

or a large growth of unknown ori-

“ gin may be suspected to be thy-

roid tissue. ©

In sucn cases it may be useful
to inject a radioactive isotope of
iodine into the blood stream.
Functioning thyroid tissue, what-
ever its location, will pick out and
remove the radioiodine from the

blood. If then a detecting instru-.
ment is moved about over the

patient’s throat and chest, rays
will be registered as coming from
each area in which thyroid tissue
is located.

“Of course, the dose of radio--

/

thyroid which is impossible to
locate and remove surgically.

Fortunately, in the case of io-
dine the amount of radiation re-
ceived from a single dose is limit-
ed by the relatively short “half
life” of radioactive iodine. That
is, the number of rays emitted
from any given amount of a ra-
dioisotope decreases with time at
such a rate that only half as many
rays are sent out per minute at
the end of the time of half-life as
were sent out at the beginning.
The half-life of the commonly
used radioisotope of iodine, iodine
131, is 8 days.

rence. although the dose first
injected into the patient may be
quite radioactive, at the end of
8 days it will be only half as
radioactive as it was at first. At
the end of the following 8 days,
it will be only one-quarter as
active as it was at first. Thus, at
the end of 80 days practically no
activity remains.

The patient is thus rid of his
disease and his radioactivity at
the same time. The physician
has also lost the radioisotopic
jodine remaining on his shelves
at the end of this time, for the
disappearance (called decay) of
radioactivity expressed by the
half life is an inherent property
of the isotope and will occur at
exactly the same rate whether or
not the isotope is put to use.
oe :

Other medically useful radio-
isotopes include phosphorus ° 32,
with a half life of 14 days; gold
199, with a half-life of 3 days,
and carbon 14, with a half-life of
5,000 years. Because of its long
half-life, carbon 14 is particularly

dangerous and is not used on hu- .

man beings at the present time.

However, it is valuable in tracing .

experiments where animals are
used instead of patients to locate
the site of action of various drugs.

Since the earth is at least two
billion years old, it is evident that

- any iodine 131, phosphorous 32 or

active iodine must be such that ©

the rays do not destroy more liv-
ing tissue than is desirable. But
with proper dosage, it is possible
to reach and destroy cancerous

In Yugoslavia ‘no ho

_—LONDON

‘ODAY the people of Yugosla-

via hate Marshal Tito as much

as they formerly revered him,

and 95 percent of the Yugoslavs

who returned to their country

from Canada, Australia and New

Zealand would leave tomorrow if
they were permitted.

The workers’ standard of | liv-
ing is deteriorating rapidly, while
prices rise but wages are pegged.

This is what Dr. Leslie Jury,
who went from Australia to Yu-
goslavia in March, 1948, stated on
his arrival in London recently. |

Dr. Jury relates how the eco-

nomic and political conditions of
the workers and peasants there

have deteriorated as a result of —

the Tito-Rankovic clique’s betray-
al of socialism.

“When I arrived there,’ he
said, “I found things not too
good. Food was scarce and of

velly poor quailty. Wages were .

low and the people were discon-
tented with the way in which
things had grown worse since
the end of the war. :

_ “In 1945 and 1946 life was not
too bad, and the people were full
of enthusiasm, but from 1947
things began to go to pieces. The
Five Year Plan was begun before

' the country got back to the pre-

war level, and even now you can .

see thousands of roofless houses
in Dalmatia.

“The Plan has definitely failed;
everything is behind schedule; it
could never have succeeded with-
out outside help; that is why Tito
is on his knees begging to the
US imperialists for dollars to
‘build socialism’. :

“In 1947/48 the workers’ stan-

_ dard of living dropped 50 per-

cent owing to rising prices, and
in the past year prices have
again risen 100 percent, while
wages have been rigidly peg-
ged.

The average worker receives
about 3,000 dinars a month wages.
Coffee costs 1000 dinars a kilo
(about 2% 1b.), pork fat from 500
to 1000 dinars a kilo, butter,
cheese, bacon, 450 dinars a kilo,
eggs. 15 to 20 dinars each, a pair
of shoes 4,500 to 7,000 dinars and
an overcoat 14,000 dinars.

ne

gold 199 which may have been
present at the beginning has long
since disappeared. Even carbon
14, with a half-life of 5,000 years
decays into insignificance in 50,-
000 years. Therefore, isotopes
similar to those were unknown
to medicine until after the inven-
tion of the cyclotron in 1931.

The cyclotron is a machine that
directs a stream of small, sub-
atomic particles (parts of atoms)
against a target of intact atoms.
Some of the atoms in the target
are altered by the subatomic par-
ticles and become tadioisotopes.
Medically useful ‘radjoactive
atoms are made with the cyclo-

nest man is

“There are rations of sugar,
pork fat, meatyand bread. Until
four months ago we were getting
oil, coffee and soap in the ration,
but since May these have. disap-
peaied, and the ration of sugar
and fat has been cut by 50 per
cent.

“These are the ‘successful’ re-
sults of the Tito agricultural pro-
gram.

“A worker on highest rations
gets a kilo of meat (about 2 Ib.)
a week, but there have been many
weeks when there has been no
meat at all.

“The ordinary worker works
eight hours a day and, in addi-
tion, does about 10 hours a week
‘voluntary’ work, digging roads
and mixing concrete. He also
has to attend an average of five
‘political’ meetings a week, last-
ing from one to. four hours.

“Paid overtime has been abo-,

lished and the worker is com-
pelled to do as much overtime as
the bosses order. :

“All housewives, and even in-

valid and old-age pensioners are —
“compelled to do ‘voluntary’ labor,

including pick. and shovel work

' ecards,

tron. However, this is a slow
and expensive process, yielding
small amounts of the desired ma-
terial. For this reason, medical
application of cyclotron-produced
isotopes was, and is, quite limited.
e : 4

Mankind’s ability to make radio-
active isotopes was enormously
increased by the construction, be-
ginning in December, 1942, of a
number of nuclear reactors, or
atomic piles. The ability of a pile.
to produce radioisotopes is so
great that the entire demand of
the United States and about 20
foreign nations for pile-produced
isotopes for industry and medi-
cine is at present easily satisfied
by the facilities at the Clinton
pile in Tennessee.

A pile is a fertile source of iso-
topes because in it chemical sub-
stances are continuously bathed
in a “sea” of subatomic particles
of a type particularly effective in
bringing about atomic changes.
These very effective particles are
slow neutrons, a type of particle
which cannot be handled in a
cyclotron. In order to produce
radioisotopes all that is required
is to place the proper chemicals
inside of the reactor for a few
days, hours or even minutes.

' The chain reactor continuously
produces neutrons by releasing
these parts of atoms from atoms
of uranium. The neutrons are
released from the uranium at the
instant the uranium atom splits
apart in fission reaction

The fission reaction is a pro-
cess similar to that which occurs
in the explosion of an atomic
bomb, except that in a chain
reacting pile the process is not
allowed to approach an explosive
rate. The neutrons produced in
the fission permeate the entire
interior of the reactor, including
the chemicals placed therein for
activation.

When the chemical is with-
drawn from the pile, a greater
or lesser number of its atoms will
be found to have become radio-
active. Since the quantity of an
isotope necessary for medical pur-
poses is quite small, and since a
great many chemicals may be
placed in the pile at one time,
there is no difficulty in producing
sufficient radioactive material to
fill all requests.

As with so many other scien-
tific developments, radioactivity
and nuclear reactors may be used
to do either good or evil. In no
other achievement of mankind,
however, are these two alterna-
tives so clearly apparent—and so
greatly contrasted. ‘ :

on the roads. Those who refuse
are labelled “enemies of the peo-

ple,”

homes.

“The Tito press is full of at-:
tacks on the Soviet Union, the
Democracies and the

People’s
Communist parties of all coun-
tries, in almost the same langu-
age as that used by Hitler.

“There are thousands of partis-

ans, Communists, and other pat-

riots in the prisons, and they are

subjected to all kinds of vile tor-
tures,
“In Dalmatia, the Titoites have

tried to starve the peasants into

submission by cutting off their
corn ration, but the peasants

would rather starve than enter
the Tito “collectives”, which are _

controlled by boards of village
loafers and Kulaks.

“Today no honest man in Yu-
goslavia is a Tito man and Tito
has no mass support. It is con-
sidered in Yugoslavia to be one’s

patriotic duty to do everything to”

get rid of the leaders who are

selling their country and their

people to a foreign power.”

PACIFIC TRIBUNE — NOVEMBER %, 1919 — PAGE 5

deprived of their ration
and evicted from their