12 February 2009
Blood transfusion
The invention: A technique that greatly enhanced surgery patients’
chances of survival by replenishing the blood they lose in
surgery with a fresh supply.
The people behind the invention:
Charles Drew (1904-1950), American pioneer in blood
transfusion techniques
George Washington Crile (1864-1943), an American surgeon,
author, and brigadier general in the U.S. Army Medical
Officers’ Reserve Corps
Alexis Carrel (1873-1944), a French surgeon
Samuel Jason Mixter (1855-1923), an American surgeon
Nourishing Blood Transfusions
It is impossible to say when and where the idea of blood transfusion
first originated, although descriptions of this procedure are
found in ancient Egyptian and Greek writings. The earliest documented
case of a blood transfusion is that of Pope Innocent VII. In
April, 1492, the pope, who was gravely ill, was transfused with the
blood of three young boys. As a result, all three boys died without
bringing any relief to the pope.
In the centuries that followed, there were occasional descriptions
of blood transfusions, but it was not until the middle of the seventeenth
century that the technique gained popularity following the
English physician and anatomistWilliam Harvey’s discovery of the
circulation of the blood in 1628. In the medical thought of those
times, blood transfusion was considered to have a nourishing effect
on the recipient. In many of those experiments, the human recipient
received animal blood, usually from a lamb or a calf. Blood transfusion
was tried as a cure for many different diseases, mainly those
that caused hemorrhages, as well as for other medical problems and
even for marital problems.
Blood transfusions were a dangerous procedure, causing many
deaths of both donor and recipient as a result of excessive blood loss, infection, passage of blood clots into the circulatory systems of
the recipients, passage of air into the blood vessels (air embolism),
and transfusion reaction as a result of incompatible blood types. In
the mid-nineteenth century, blood transfusions from animals to humans
stopped after it was discovered that the serum of one species
agglutinates and dissolves the blood cells of other species. A sharp
drop in the use of blood transfusion came with the introduction of
physiologic salt solution in 1875. Infusion of salt solution was simple
and was safer than blood transfusion.Direct-Connection Blood Transfusions
In 1898, when GeorgeWashington Crile began his work on blood
transfusions, the major obstacle he faced was solving the problem of
blood clotting during transfusions. He realized that salt solutions
were not helpful in severe cases of blood loss, when there is a need to
restore the patient to consciousness, steady the heart action, and raise
the blood pressure. At that time, he was experimenting with indirect
blood transfusions by drawing the blood of the donor into a vessel,
then transferring it into the recipient’s vein by tube, funnel, and cannula,
the same technique used in the infusion of saline solution.
The solution to the problem of blood clotting came in 1902 when
Alexis Carrel developed the technique of surgically joining blood
vessels without exposing the blood to air or germs, either of which
can lead to clotting. Crile learned this technique from Carrel and
used it to join the peripheral artery in the donor to a peripheral vein
of the recipient. Since the transfused blood remained sealed in the
inner lining of the vessels, blood clotting did not occur.
The first human blood transfusion of this type was performed by
Crile in December, 1905. The patient, a thirty-five-year-old woman,
was transfused by her husband but died a few hours after the procedure.
The second, but first successful, transfusion was performed on
August 8, 1906. The patient, a twenty-three-year-old male, suffered
from severe hemorrhaging following surgery to remove kidney
stones. After all attempts to stop the bleeding were exhausted with
no results, and the patient was dangerously weak, transfusion was
considered as a last resort. One of the patient’s brothers was the dofew days later, another transfusion was done. This time, too, he
showed remarkable improvement, which continued until his complete
recovery.
For his first transfusions, Crile used the Carrel suture method,
which required using very fine needles and thread. It was a very
delicate and time-consuming procedure. At the suggestion of Samuel
Jason Mixter, Crile developed a new method using a short tubal
device with an attached handle to connect the blood vessels. By this
method, 3 or 4 centimeters of the vessels to be connected were surgically
exposed, clamped, and cut, just as under the previous method.
Yet, instead of suturing of the blood vessels, the recipient’s vein was
passed through the tube and then cuffed back over the tube and tied
to it. Then the donor’s artery was slipped over the cuff. The clamps
were opened, and blood was allowed to flow from the donor to the
recipient. In order to accommodate different-sized blood vessels,
tubes of four different sizes were made, ranging in diameter from
1.5 to 3 millimeters.Impact,
Crile’s method was the preferred method of blood transfusion
for a number of years. Following the publication of his book on
transfusion, a number of modifications to the original method were
published in medical journals. In 1913, Edward Lindeman developed
a method of transfusing blood simply by inserting a needle
through the patient’s skin and into a surface vein, making it for the
first time a nonsurgical method. This method allowed one to measure
the exact quantity of blood transfused. It also allowed the donor
to serve in multiple transfusions. This development opened the
field of transfusions to all physicians. Lindeman’s needle and syringe
method also eliminated another major drawback of direct
blood transfusion: the need to have both donor and recipient right
next to each other.
Birth control pill
The invention: An orally administered drug that inhibits ovulation
in women, thereby greatly reducing the chance of pregnancy.
The people behind the invention:
Gregory Pincus (1903-1967), an American biologist
Min-Chueh Chang (1908-1991), a Chinese-born reproductive
biologist
John Rock (1890-1984), an American gynecologist
Celso-Ramon Garcia (1921- ), a physician
Edris Rice-Wray (1904- ), a physician
Katherine Dexter McCormick (1875-1967), an American
millionaire
Margaret Sanger (1879-1966), an American activist
An Ardent Crusader
Margaret Sanger was an ardent crusader for birth control and
family planning. Having decided that a foolproof contraceptive was
necessary, Sanger met with her friend, the wealthy socialite Katherine
Dexter McCormick. A1904 graduate in biology from the Massachusetts
Institute of Technology, McCormick had the knowledge
and the vision to invest in biological research. Sanger arranged a
meeting between McCormick and Gregory Pincus, head of the
Worcester Institutes of Experimental Biology. After listening to Sanger’s
pleas for an effective contraceptive and McCormick’s offer of financial
backing, Pincus agreed to focus his energies on finding a pill
that would prevent pregnancy.
Pincus organized a team to conduct research on both laboratory
animals and humans. The laboratory studies were conducted under
the direction of Min-Chueh Chang, a Chinese-born scientist who
had been studying sperm biology, artificial insemination, and in vitro
fertilization. The goal of his research was to see whether pregnancy
might be prevented by manipulation of the hormones usually
found in a woman.It was already known that there was one time when a woman
could not become pregnant—when she was already pregnant. In
1921, Ludwig Haberlandt, an Austrian physiologist, had transplanted
the ovaries from a pregnant rabbit into a nonpregnant one.
The latter failed to produce ripe eggs, showing that some substance
from the ovaries of a pregnant female prevents ovulation. This substance
was later identified as the hormone progesterone by George
W. Corner, Jr., and Willard M. Allen in 1928.
If progesterone could inhibit ovulation during pregnancy, maybe
progesterone treatment could prevent ovulation in nonpregnant females
as well. In 1937, this was shown to be the case by scientists
from the University of Pennsylvania, who prevented ovulation in
rabbits with injections of progesterone. It was not until 1951, however,
when Carl Djerassi and other chemists devised inexpensive
ways of producing progesterone in the laboratory, that serious consideration
was given to the medical use of progesterone. The synthetic
version of progesterone was called “progestin.”
Testing the Pill
In the laboratory, Chang tried more than two hundred different
progesterone and progestin compounds, searching for one that
would inhibit ovulation in rabbits and rats. Finally, two compounds
were chosen: progestins derived from the root of a wild Mexican
yam. Pincus arranged for clinical tests to be carried out by Celso-
Ramon Garcia, a physician, and John Rock, a gynecologist.
Rock had already been conducting experiments with progesterone
as a treatment for infertility. The treatment was effective in some
women but required that large doses of expensive progesterone be
injected daily. Rock was hopeful that the synthetic progestin that
Chang had found effective in animals would be helpful in infertile
women as well. With Garcia and Pincus, Rock treated another
group of fifty infertile women with the synthetic progestin. After
treatment ended, seven of these previously infertile women became
pregnant within half a year. Garcia, Pincus, and Rock also took several
physiological measurements of the women while they were
taking the progestin and were able to conclude that ovulation did
not occur while the women were taking the progestin pill.Having shown that the hormone could effectively prevent ovulation
in both animals and humans, the investigators turned their attention
back to birth control. They were faced with several problems:
whether side effects might occur in women using progestins for a
long time, and whether women would remember to take the pill day
after day, for months or even years. To solve these problems, the birth
control pill was tested on a large scale. Because of legal problems in
the United States, Pincus decided to conduct the test in Puerto Rico.
The test started in April of 1956. Edris Rice-Wray, a physician,
was responsible for the day-to-day management of the project. As
director of the Puerto Rico Family Planning Association, she had
seen firsthand the need for a cheap, reliable contraceptive. The
women she recruited for the study were married women from a
low-income population living in a housing development in Río
Piedras, a suburb of San Juan. Word spread quickly, and soon
women were volunteering to take the pill that would prevent pregnancy.
In the first study, 221 women took a pill containing 10 milligrams
of progestin and 0.15 milligrams of estrogen. (The estrogen
was added to help control breakthrough bleeding.)
Results of the test were reported in 1957. Overall, the pill proved
highly effective in preventing conception. None of the women
who took the pill according to directions became pregnant, and
most women who wanted to get pregnant after stopping the pill
had no difficulty. Nevertheless, 17 percent of the women had some
unpleasant reactions, such as nausea or dizziness. The scientists
believed that these mild side effects, as well as one death from congestive
heart failure, were unrelated to the use of the pill.
Even before the final results were announced, additional field
tests were begun. In 1960, the U.S. Food and Drug Administration
(FDA) approved the use of the pill developed by Pincus and his collaborators
as an oral contraceptive.Consequences
Within two years of approval by the FDA, more than a million
women in the United States were using the birth control pill. New
contraceptives were developed in the 1960’s and 1970’s, but the
birth control pill remains the most widely used method of preventing pregnancy. More than 60
million women use the pill
worldwide.
The greatest impact of the
pill has been in the social and
political world. Before Sanger
began the push for the pill,
birth control was regarded often
as socially immoral and
often illegal as well. Women
in those post-World War II
years were expected to have
a lifelong career as a mother
to their many children.
With the advent of the pill,
a radical change occurred
in society’s attitude toward
women’s work.Women had increased
freedom to work and enter careers previously closed to them
because of fears that they might get pregnant. Women could control
more precisely when they would get pregnant and how many children
they would have. The women’s movement of the 1960’s—with its
change to more liberal social and sexual values—gained much of its
strength from the success of the birth control pill.
10 February 2009
BINAC computer
The invention: The world’s first electronic general-purpose digital
computer.
The people behind the invention:
John Presper Eckert (1919-1995), an American electrical engineer
John W. Mauchly (1907-1980), an American physicist
John von Neumann (1903-1957), a Hungarian American
mathematician
Alan Mathison Turing (1912-1954), an English mathematician
Computer Evolution
In the 1820’s, there was a need for error-free mathematical and
astronomical tables for use in navigation, unreliable versions of
which were being produced by human “computers.” The problem
moved English mathematician and inventor Charles Babbage to design
and partially construct some of the earliest prototypes of modern
computers, with substantial but inadequate funding from the
British government. In the 1880’s, the search by the U.S. Bureau of
the Census for a more efficient method of compiling the 1890 census
led American inventor Herman Hollerith to devise a punched-card
calculator, a machine that reduced by several years the time required
to process the data.
The emergence of modern electronic computers began during
World War II (1939-1945), when there was an urgent need in the
American military for reliable and quickly produced mathematical
tables that could be used to aim various types of artillery. The calculation
of very complex tables had progressed somewhat since
Babbage’s day, and the human computers were being assisted by
mechanical calculators. Still, the growing demand for increased accuracy
and efficiency was pushing the limits of these machines.
Finally, in 1946, following three years of intense work at the University
of Pennsylvania’s Moore School of Engineering, John Presper
Eckert and John W. Mauchly presented their solution to the problems
in the form of the Electronic Numerical Integrator and Calculator (ENIAC) the world’s first electronic general-purpose digital
computer.
The ENIAC, built under a contract with the Army’s Ballistic Research
Laboratory, became a great success for Eckert and Mauchly,
but even before it was completed, they were setting their sights on
loftier targets. The primary drawback of the ENIAC was the great
difficulty involved in programming it. Whenever the operators
needed to instruct the machine to shift from one type of calculation
to another, they had to reset a vast array of dials and switches, unplug
and replug numerous cables, and make various other adjustments
to the multiple pieces of hardware involved. Such a mode of
operation was deemed acceptable for the ENIAC because, in computing
firing tables, it would need reprogramming only occasionally.
Yet if instructions could be stored in a machine’s memory, along
with the data, such a machine would be able to handle a wide range
of calculations with ease and efficiency.
The Turing Concept
The idea of a stored-program computer had first appeared in a
paper published by English mathematician Alan Mathison Turing
in 1937. In this paper, Turing described a hypothetical machine of
quite simple design that could be used to solve a wide range of logical
and mathematical problems. One significant aspect of this imaginary
Turing machine was that the tape that would run through it
would contain both information to be processed and instructions on
how to process it. The tape would thus be a type of memory device,
storing both the data and the program as sets of symbols that the
machine could “read” and understand. Turing never attempted to
construct this machine, and it was not until 1946 that he developed a
design for an electronic stored-program computer, a prototype of
which was built in 1950.
In the meantime, John von Neumann, a Hungarian American
mathematician acquainted with Turing’s ideas, joined Eckert and
Mauchly in 1944 and contributed to the design of ENIAC’s successor,
the Electronic Discrete Variable Automatic Computer (EDVAC), another
project financed by the Army. The EDVAC was the first computer
designed to incorporate the concept of the stored program.In March of 1946, Eckert and Mauchly, frustrated by a controversy
over patent rights for the ENIAC, resigned from the
Moore School. Several months later, they formed the Philadelphiabased
Electronic Control Company on the strength of a contract
from the National Bureau of Standards and the Census Bureau to
build a much grander computer, the Universal Automatic Computer
(UNIVAC). They thus abandoned the EDVAC project, which
was finally completed by the Moore School in 1952, but they incorporated
the main features of the EDVAC into the design of the
UNIVAC.
Building the UNIVAC, however, proved to be much more involved
and expensive than anticipated, and the funds provided by
the original contract were inadequate. Eckert and Mauchly, therefore,
took on several other smaller projects in an effort to raise
funds. On October 9, 1947, they signed a contract with the Northrop
Corporation of Hawthorne, California, to produce a relatively small
computer to be used in the guidance system of a top-secret missile
called the Snark, which Northrop was building for the Air Force.
This computer, the Binary Automatic Computer (BINAC), turned
out to be Eckert and Mauchly’s first commercial sale and the first
stored-program computer completed in the United States.
The BINAC was designed to be at least a preliminary version of a
compact, airborne computer. It had two main processing units.
These contained a total of fourteen hundred vacuum tubes, a drastic
reduction from the eighteen thousand used in the ENIAC. There
were also two memory units, as well as two power supplies, an input
converter unit, and an input console, which used either a typewriter
keyboard or an encoded magnetic tape (the first time such
tape was used for computer input). Because of its dual processing,
memory, and power units, the BINAC was actually two computers,
each of which would continually check its results against those of
the other in an effort to identify errors.
The BINAC became operational in August, 1949. Public demonstrations
of the computer were held in Philadelphia from August 18
through August 20.Impact
The design embodied in the BINAC is the real source of its significance.
It demonstrated successfully the benefits of the dual processor
design for minimizing errors, a feature adopted in many subsequent
computers. It showed the suitability of magnetic tape as an
input-output medium. Its most important new feature was its ability
to store programs in its relatively spacious memory, the principle
that Eckert, Mauchly, and von Neumann had originally designed
into the EDVAC. In this respect, the BINAC was a direct descendant
of the EDVAC.
In addition, the stored-program principle gave electronic computers
new powers, quickness, and automatic control that, as they
have continued to grow, have contributed immensely to the aura of
intelligence often associated with their operation.
The BINAC successfully demonstrated some of these impressive
new powers in August of 1949 to eager observers from a number of
major American corporations. It helped to convince many influential
leaders of the commercial segment of society of the promise of
electronic computers. In doing so, the BINAC helped to ensure the
further evolution of computers.
See also Apple II computer; BINAC computer; Colossus computer;
ENIAC computer; IBM Model 1401 computer; Personal computer;
Supercomputer; UNIVAC computer.
Bathysphere
The invention: The first successful chamber for manned deep-sea
diving missions.
The people behind the invention:
William Beebe (1877-1962), an American naturalist and curator
of ornithology
Otis Barton (1899- ), an American engineer
John Tee-Van (1897-1967), an American general associate with
the New York Zoological Society
Gloria Hollister Anable (1903?-1988), an American research
associate with the New York Zoological Society
Inner Space
Until the 1930’s, the vast depths of the oceans had remained
largely unexplored, although people did know something of the
ocean’s depths. Soundings and nettings of the ocean bottom had
been made many times by a number of expeditions since the 1870’s.
Diving helmets had allowed humans to descend more than 91 meters
below the surface, and the submarine allowed them to reach a
depth of nearly 120 meters. There was no firsthand knowledge,
however, of what it was like in the deepest reaches of the ocean: inner
space.
The person who gave the world the first account of life at great
depths wasWilliam Beebe. When he announced in 1926 that he was
attempting to build a craft to explore the ocean, he was already a
well-known naturalist. Although his only degrees had been honorary
doctorates, he was graduated as a special student in the Department
of Zoology of Columbia University in 1898. He began his lifelong
association with the New York Zoological Society in 1899.
It was during a trip to the Galápagos Islands off the west coast of
South America that Beebe turned his attention to oceanography. He
became the first scientist to use a diving helmet in fieldwork, swimming
in the shallow waters. He continued this shallow-water work
at the new station he established in 1928, with the permission of English authorities, on the tiny island of Nonesuch in the Bermudas.
Beebe realized, however, that he had reached the limits of the current
technology and that to study the animal life of the ocean depths
would require a new approach.
A New Approach
While he was considering various cylindrical designs for a new
deep-sea exploratory craft, Beebe was introduced to Otis Barton.
Barton, a young New Englander who had been trained as an engineer
at Harvard University, had turned to the problems of ocean
diving while doing postgraduate work at Columbia University. In
December, 1928, Barton brought his blueprints to Beebe. Beebe immediately
saw that Barton’s design was what he was looking for,
and the two went ahead with the construction of Barton’s craft.
The “bathysphere,” as Beebe named the device, weighed 2,268
kilograms and had a diameter of 1.45 meters and steel walls 3.8 centimeters
thick. The door, weighing 180 kilograms, would be fastened
over a manhole with ten bolts. Four windows, made of fused
quartz, were ordered from the General Electric Company at a cost of
$500 each. A 250-watt water spotlight lent by the Westinghouse
Company provided the exterior illumination, and a telephone lent
by the Bell Telephone Laboratory provided a means of communicating
with the surface. The breathing apparatus consisted of two oxygen
tanks that allowed 2 liters of oxygen per minute to escape into
the sphere. During the dive, the carbon dioxide and moisture were
removed, respectively, by trays containing soda lime and calcium
chloride. A winch would lower the bathysphere on a steel cable.
In early July, 1930, after several test dives, the first manned dive
commenced. Beebe and Barton descended to a depth of 244 meters.
A short circuit in one of the switches showered them with sparks
momentarily, but the descent was largely a success. Beebe and
Barton had descended farther than any human.
Two more days of diving yielded a final dive record of 435 meters
below sea level. Beebe and the other members of his staff (ichthyologist
John Tee-Van and zoologist Gloria Hollister Anable) saw many
species of fish and other marine life that previously had been seen
only after being caught in nets. These first dives proved that an undersea exploratory craft had potential value, at least for deep water.
After 1932, the bathysphere went on display at the Century of Progress
Exhibition in Chicago.
In late 1933, the National Geographic Society offered to sponsor
another series of dives. Although a new record was not a stipulation,
Beebe was determined to supply one. The bathysphere was
completely refitted before the new dives.
An unmanned test dive to 920 meters was made on August 7,
1934, once again off Nonesuch Island. Minor adjustments were
made, and on the morning of August 11, the first dive commenced,
attaining a depth of 765 meters and recording a number of new scientific
observations. Several days later, on August 15, the weather
was again right for the dive.
This dive also paid rich dividends in the number of species of
deep-sea life observed. Finally, with only a few turns of cable left on
the winch spool, the bathysphere reached a record depth of 923 meters—
almost a kilometer below the ocean’s surface.Impact
Barton continued to work on the bathysphere design for some
years. It was not until 1948, however, that his new design, the
benthoscope, was finally constructed. It was similar in basic design
to the bathysphere, though the walls were increased to withstand
greater pressures. Other improvements were made, but the essential
strengths and weaknesses remained. On August 16, 1949, Barton,
diving alone, broke the record he and Beebe had set earlier,
reaching a depth of 1,372 meters off the coast of Southern California.
The bathysphere effectively marked the end of the tethered exploration
of the deep, but it pointed the way to other possibilities.
The first advance in this area came in 1943, when undersea explorer
Jacques-Yves Cousteau and engineer Émile Gagnan developed the
Aqualung underwater breathing apparatus, which made possible
unfettered and largely unencumbered exploration down to about
60 meters. This was by no means deep diving, but it was clearly a
step along the lines that Beebe had envisioned for underwater research.
A further step came in the development of the bathyscaphe by
102 / Bathysphere
Auguste Piccard, the renowned Swiss physicist, who, in the 1930’s,
had conquered the stratosphere in high-altitude balloons. The bathyscaphe
was a balloon that operated in reverse. Aspherical steel passenger
cabin was attached beneath a large float filled with gasoline
for buoyancy. Several tons of iron pellets held by electromagnets
acted as ballast. The bathyscaphe would sink slowly to the bottom
of the ocean, and when its passengers wished to return, the ballast
would be dumped. The craft would then slowly rise to the surface.
On September 30, 1953, Piccard touched bottom off the coast of Italy,
some 3,000 meters below sea level.
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