The Scientific Ravi 2014
BIOTECHNOLOGY
Peeking into the past
(The Harvard University Gazette, December
16, 1999.)
CHEMISTRY
The figure shows Crick‟s original sketch of the
structure of DNA. It was not until 1953 that
James Watson and Francis Crick used the
results of work by Rosalind Franklin and
others to work out the basic structure of the
DNA molecule. It was suggested by Watson
and Crick that the two strands of the DNA
molecule could split apart in order for the
nucleotides to be added in front of each strand
thus forming complementary strands along
each half of the original molecule.
(J.D. Watson and F.H.C. Crick. 1953. “A
Structure for Deoxyribonucleic Acid. Nature.
171: 737-738.)
In 1926, James B. Sumner crystallised urease
from Canavalia ensiformis (jackbean), which
proved to be a fundamental step in proving
that enzymes are proteins. It was the first
protein crystal ever obtained and it won
Sumner a Nobel Prize in Chemistry in 1946.
Ureases (urea amidohydrolases; EC 3.5.1.5)
are nickel-dependent enzymes which catalyse
the hydrolysis of urea into 1 molecule of
carbon dioxide and 2 molecules of ammonia.
(J.B. Sumner. 1926. “The Isolation and
Crystallisation of the Enzyme Urease.” J. Biol.
Chem. 69:435-441.)
COMPUTER SCIENCE
BOTANY
The water lily‟s origin dates back to more than
140 million years. Amborella is the remaining
species of this lineage and is now found in
only one place in the world – New Caledonia
(a small tropical island in a remote corner of
the southwest Pacific). It is a shrub with small,
not-so-impressive flowers. Thus it is the oldest
known flowering plant which has been
identified by genes.
Government College University, Lahore
In 1822, Charles Babbage made a difference
engine to compute values of polynomial
functions. It was created to calculate a series
of values automatically. It became possible to
avoid multiplication and division by using the
method of finite differences. Some parts of the
original prototype are kept in the Museum of
the History of Science, Oxford. Had it been
completed it would have comprised around
25,000 parts, weighing 13.6 tons and would
have been 2.4 m tall.
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(A. Hyman. 1985. Charles Babbage: Pioneer
of the Computer. Princeton University Press.
p. 115.)
ECONOMICS
Peeking into the past
of induction. It was first observed in 1824 by
François Arago though his observations were
given a conclusion by Michael Faraday. In
conductors with zero resistivity, eddy currents
generate heat and electromagnetic forces. The
former can be used in induction heating, while
the latter can be used to produce a strong
braking effect and levitation. On the contrary,
eddy currents may have undesirable effects in
transformers. The losses may, however, be
minimised by lamination.
(R. Wangsness. Electromagnetic Fields. 2nd
ed. O. 387-388.)
Supply-and-demand model is a model for
understanding the determination of the price of
quantity of a good sold in the market. The
explanation works by looking at two different
groups – buyers and sellers – and asking how
they interact. In other words, it is an economic
model of price determination in a market in
microeconomics. The four basic laws of this
model are:
1. If demand increases and supply remains
unchanged, a shortage occurs which leads
to a higher equilibrium price.
2. If demand decreases and price remains
unchanged, a surplus occurs which leads
to a lower equilibrium price.
3. If supply increases and demand remains
unchanged, a surplus increases which
leads to a lower equilibrium price.
4. If supply decreases and demand remains
unchanged, a shortage occurs which leads
to a higher equilibrium price.
(A. Smith. 1776. “An Inquiry into the Nature
and Causes of the Wealth of Nations.”)
ELECTRICAL ENGINEERING
Eddy currents, also known as Foucault
currents, are induced within conductors by a
changing magnetic field due to Faraday‟s law
Government College University, Lahore
ENVIRONMENTAL SCIENCE
Silent Spring is a book authored by Rachel
Carson and was published on September
27, 1962. Silent Spring presents a view of
nature
compromised
by
synthetic
pesticides, especially DDT. Once these
pesticides entered the biosphere, Carson
argued, they not only killed bugs but also
made their way up the food chain to
threaten bird and fish populations and
could eventually sicken children. The book
catalogued the environmental impacts of
the indiscriminate and uncontrolled
spraying of DDT in the USA and
questioned the logic of releasing large
amounts of chemicals into the environment
without fully understanding their effects
on ecology or human health. It was
suggested that DDT and other pesticides
may cause cancer and that their
agricultural use was a threat to wildlife,
particularly birds. Its publication was one
of the signature events in the birth of the
environmental movement, and resulted in a
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Peeking into the past
large public outcry that eventually led to
DDT being banned in 1972.
(A.R. Lovett. 2008. Supercontinent Pangaea
Pushed, Not Sucked, Into Place. National
Geographic News.)
(R. Carson. 1962. Silent Spring. Houghton
Mifflin Company, New York and P.
Brooks. 1972. The House of Life: Rachel
Carson at Work. Houghton Mifflin
Company, New York.)
MATHEMATICS
GEOGRAPHY
Al-Khwārizmī (c. 780 – c. 850 A.D.) was a
Persian mathematician, geographer and
astronomer who is often accredited of
establishing the basics of algebra and
trigonometry and is thus known as the
“Inventor of Algebra”. In his book, AlKhwārizmī gives a wide range of examples
regarding the problems in trade, legal
inheritance and surveying. The picture given
on the left is the original Arabic print
manuscript of the Book of Algebra by AlKhwārizmī, while the one on the right shows a
page from The Algebra of Al-Khwārizmī by
Frederick Rosen in English.
Pangaea was a supercontinent that formed
approximately 300 million years ago and
existed during the late Paleozoic and early
Mesozoic eras. Before its breaking apart
about 100 million years ago, much of the
land mass was in the Southern
Hemisphere. It was the first reconstructed
supercontinent and was surrounded by a
super ocean called Panthalassa. Its
existence is evident from the fossils which
show the presence of similar and identical
species on continents that are now miles
apart. To illustrate, the fossils of
freshwater reptile Mesosaurus have been
found in localised regions of the coasts of
West Africa and Brazil.
Government College University, Lahore
(C.B. Boyer. 1991. “The Arabic Hegemony.”
A History of Mathematics. 2nd ed. John Wiley
& Sons, Inc.)
MICROBIOLOGY
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There are a few things which space scientists
avoid to take outside this plant; one such entity
is the microorganisms because they could
potentially contaminate other planets other
planets the spacecraft visit. However,
Tersicoccus phoenicis (Domain: Bacterium;
Phylum:
Actinobacterium;
Class:
Actinobacteridae; Order: Actinomycetales;
Family: Micrococcaceae) was recently
collected independently from the floors of two
clean rooms (rooms where spacecrafts are
assembled) approximately 2,500 miles apart –
one in Centre Spatial Guyanais in Kourou,
French Guiana and the other in the Kennedy
Space Centre in Florida, USA. Despite
frequent sterilisation of clean rooms these
microorganism have shown to persist due to
tolerance to extreme dryness, pH, temperature
and salt concentration. The species name was
derived from “tersi”, Latin for clean; “coccus”,
Greek for bacterium‟s berry-like appearance;
and “phoenicis” to pay homage to Phoenix
lander, the spacecraft which was been
assembled in the clean room where these
bacteria were found.
(G. Webster. 2013. “Rare new microbe found
in two distinct clean rooms.” NASA.gov.
Retrieved: November 6, 2013.)
PHYSICS
Peeking into the past
(A. Salam. 1966. “Magnetic monopole and
two photon theories of C-violation.” Physics
Letters. 22(5): 683-684.)
PSYCHOLOGY
The polygraph, which is commonly known as
the „lie detector‟, was first invented in 1921,
and has been improved and updated with time.
Advancement in computer programming has
allowed for the development of sophisticated
software which allows signals to be displayed
on computer screens and helps the examiner in
identifying irregularities more efficiently. The
device is designed to display certain
physiological signs, such as heart rate, blood
pressure, respiration and skin conductivity,
which in turn allows a specialist (polygraph
examiner) to deduce whether the subject is
lying or not. We must note that polygraph
testing is not an exact science, and there is
certainly margin for error in the interpretation
of the three metrics.
STATISTICS
A magnetic photon, as predicted in 1966 by
the first Pakistani Nobel Laureate Dr. Abdus
Salam, is a hypothetical particle. It is said to
be a mixture of even and odd C-parity states
and does not couple to leptons (unlike normal
photons). It was predicted by certain
extensions of electromagnetism in order to
include magnetic monopoles. However, there
is no experimental evidence for this particle‟s
existence as several versions have been ruled
out.
Government College University, Lahore
The term “standard deviation” was first used
by Karl Pearson in 1984, initially in his
writings and later in his lectures. He replaced
the term “mean error” first used for this idea as
proposed by Gauss (now, mean error is
mathematically distinct from standard
deviation). Standard deviation (represented by
the Greek letter σ) measures the amount of
variation from the average. A high standard
deviation indicates that data points are spread
out over a large range of values, while a low
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standard deviation indicates that data points
are very close to the mean.
(H. Walker. 1931. Studies in the History of the
Statistical Method. Baltimore, MD: Williams
& Wilkins Co. p. 24-25.)
ZOOLOGY
Peeking into the past
Chironex fleckeri, more commonly known as
sea wasp, is a species of box jellyfish found in
coastal waters of New Guinea and Australia. It
is the most lethal jellyfish in the world. It is
the largest of the box jellyfish and its bell
grows to approximately the size of a
basketball. 15 tentacles trail from each corner
of the bell. Since it is virtually transparent, it is
impossible to visualise it in its natural habitat
which poses a great danger to swimmers.
When the jellyfish is swimming, its tentacles
contract and are about 15 cm long and 5 mm in
diameter. On the contrary, when it is hunting,
the tentacles get thinner and become 3 m long.
These are day hunters and appear to be
„sleeping‟ at night on the ocean floor.
(P.J. Fenner. 2000. Chironex fleckeri – the
north Australian box-jellyfish.)
Government College University, Lahore
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