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SCIENCEFORALL
Science made simple
SCIENCE FOR ALL Page 1
JULY 2009
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CONTENT
1. EDITORIAL ------------------------------------------------------------------------------------------03
2. THE GAINTS OF SCIENCE Galileo Galilei ----------------------------------------------04
3. KNOW YOUR SOLAR SYSTEM Mercury------------------------------------------------104. MATHS CORNER Vedic Mathematics--------------------------------------------------12
5. HOW DOES IT WORK? DVD Technology -------------------------------------------------16
6. THE HUMAN BODY Cell ----------------------------------------------------------------------19
SCIENCE IN NEWS Highlights of This Month---------------------------------------------22
SCIENCE FOR ALL Page 2
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he gave up this course and left without
completing his medical degree.
To earn a living, Galileo Galilei started
tutoring students in mathematics. First he
started privately in Florence and then during
1585-86, at Siena, he held a public
appointment. During the summer of 1586 he
taught at Vallombrosa, and in this year he
wrote his first scientific book The little
balance [La Balancitta] which described
Archimedes' method of finding the specific
gravities (that is the relative densities) of
substances using a balance. By this his
journey of unfolding of discoveries and
inventions started. Galileo desperately
wanted to teach mathematics at the
University of Bologna but he failed to
impress Clavius who was professor of
mathematics there. But for ambitious and
brilliant Galileo opportunities were not less.
Very soon Galileo received a prestigious
invitation to lecture on the dimensions and
location of hell in Dante's Inferno at the
Academy in Florence. In 1589 he was
appointed for chair of mathematics at
University of Pisa (same university from
which he never got the degree). When
Galileo arrived at the University, some
debate had started up on one of Aristotle's"laws" of nature that heavier objects fell
faster than lighter objects. Aristotle's word
had been accepted as gospel truth, and
there had been few attempts to test
Aristotle's conclusions by actually
conducting an experiment!
According to legend, Galileo decided to try.
He needed to drop the objects from a great
height. The perfect building was right at
hand, the Tower of Pisa, 54 meters tall.
Galileo climbed up to the top of the building
carrying a variety of balls of varying size
and weight, and dumped them off of the top.
They all landed at the base of the building at
the same time (legend says that the
demonstration was witnessed by a huge
crowd of students and professors). Like this
he proved Aristotle wrong. With the coming
of power in hand Galileo grew arrogant and
rude. It was because of this fact that the
University of Pisa chose not to renew
Galileo's contract.
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In year 1590, he wrote De Motu, a series ofessays on the theory of motion which he
never published. It is likely that he never
published this material because he was less
than satisfied with it. Actually that time he
was quite mistaken that the force acting on
a body was the relative difference between
its specific gravity and that of the substance
through which it moved. He returned to workon the theory of motion in 1602 and over the
following two years, through his study of
inclined planes and the pendulum, he
formulated the correct law of falling bodies
and worked out that a projectile follows a
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parabolic path. In 1602-1604, he completed
his work on discourses which reflected his
work on inclination. In this he assumed that
the speed acquired by the same movable
object over different inclinations of the plane
are equal whenever the heights of those
planes are equal.
In 1591, Vincenzo Galilei, Galileo's father,
died and since Galileo was the eldest son
he had to provide financial support for the
rest of the family and, in particular, have the
necessary financial means to providedowries for his two younger sisters. Being a
professor of mathematics at Pisa he was
not well paid. So Galileo looked for a more
lucrative post. Galileo was appointed
professor of mathematics at the University
of Padua (the University of the Republic of
Venice) in 1592 at a salary three times of
what he had received at Pisa. On 7December 1592 he gave his inaugural
lecture and that marked the beginning of a
period of eighteen years at the university.
These were the years that he later
described as the happiest years of his life.
At Padua his duties were mainly to teach
Euclid's geometry and standard (geocentric)
astronomy to medical students, who would
need to know some astronomy in order to
make use of astrology in their medical
practice. After this his real work of making of
telescope started for which he is
remembered the most. Galileo began to
make a series of telescopes whose optical
performance was much better than that of
the Dutch instrument. His first telescope
was made from available lenses and gave a
magnification of about four times. To
improve on this Galileo learned how to grind
and polish his own lenses and by August
1609 he had an instrument with a
magnification of around eight or nine.
Galileo immediately saw the commercial
and military applications of his telescope
(which he called a perspicillum) for ships at
sea. In about two months, December and
January, he made more discoveries that
changed the world than anyone has ever
made before or since, as had turned his
telescope on the night sky and began to
make remarkable discoveries. Galileos
astronomical discoveries are described in a
short book called the Starry Messenger
published in Venice in May 1610.
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Galileo never married. However, he had
brief relationship with Marina Gamba, a
woman he met on one of his many trips to
Venice. Marina lived in Galileo's house in
Padua where she bore him three children,
two daughters Virginia and Livia and son
Vincenzio. In 1610, Galileo moved from
Padua to Florence where he took a position
at the Court of the Medici family. He left
Vincenzio, with Marina Gamba in Padua. In
1613, Marina married Giovanni Bartoluzzi,
and Vincenzio joined his father in Florence.
http://www-history.mcs.st-andrews.ac.uk/Mathematicians/Euclid.htmlhttp://www-history.mcs.st-andrews.ac.uk/Mathematicians/Euclid.html8/14/2019 Science for All July edition
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For Galileo saying that the Earth went
around the sun changed everything since
he was contradicting the techings of the
church, While some of the churchs
mathematicians wrote that his observations
were clearly correct, many members of the
church believed thathe must be wrong.
Galileo Galilei was 68 years old and sick.
Threatened with torture, he publicly
confessed that he had been wrong to have
said that the Earth moves around the Sun.
Legend then has it that after his confession
Galileo quietly whispered but yet, it.
Galileo Galilei was a religious man, and
agreed that the Bible could never be wrong.
However, he said, the interpreters of the
Bible could make mistakes, and it was a
mistake to assume that the Bible had to be
taken literally. This might have been one of
Galileo's major mistakes. At that time, only
Church priests were allowed to interpret the
Bible, or to define God's intentions. So there
were lots of controversies & oppositions on
this and his discovery that earth moves
around sun. In December of 1613, a
powerful member of the nobility said that
she could not see how his observations
could be true, since they would contradict
the Bible. The lady quoted a passage in
Joshua where God causes the Sun to stand
still and lengthen the day. How could this
mean anything other than that the Sun went
around earth?
moves." Galileo died of natural causes in
1642, after having gone blind. It was a sad
end for such a great a man to die
condemned of heresy. He wished to be
buried beside his father in the family tomb in
the Basilica of Santa Croce, but there were
lot of opposition from the Church. He was
reburied at Santa Croce, sacred ground, in
1737. In 1741, Pope Benedict XIV
authorized publication of Galileo's complete
works. Heliocentrism was formally
rescinded as heresy in 1758.
It was not until October 31, 1992, that the
Church under Pope John Paul II expressed
regret over how Galileo had been treated, in
response to a Pontifical Council for Culture
study. Galileo Galilei is one of the most
influential and famous scientists in human
history, having contributed to a wide range
of fields.
Necessity is the Mother of Invention
Galileo Galilei
Scientific achievements:
Kinematics:
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At age twenty, Galileo noticed a lamp
swinging. Curious mind of Galileo wanted to
know how long it took the lamp to swing
back and forth; he used his pulse to time
large and small swings. Galileo discovered
something that no one else had ever
realized: the period of each swing was
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exactly the same. He formulated the times-
squared law, which states that the vertical
distance covered by an object in free fall or
along an inclined plane is proportional of the
square of the time of the fall.
S= gt2/2
He also identified the parabola as the ideal
trajectory for uniformly accelerated motion
in plane.
He was the one who proposed a principle of
inertia, which became the foundation of
Newtons First law motion.
Astronomy:
In 1608, the telescope was invented in the
Netherlands. Over the next year, Galileo
gave his own improvements on this
invention. As this scientist trained his
telescope on the objects of sky, he viewed a
surface that was uneven, rough, and full of
cavities and prominences. Later it was
realized that this was the view of the surface
of moon. He continued his work of
improvement of power of his telescope. On
January 7, 1610, he turned his 30 power
telescope towards Jupiter, and found three
small, bright stars near the planet. One was
off to the west, the other two were to the
east, all three in a straight line. Thefollowing evening, Galileo once again took a
look at Jupiter, and found that all three of
the "stars" were now west of the planet, still
in a straight line. Observations over the
following weeks lead Galileo to the
inescapable conclusion that these small
"stars" were actually small satellites that
were rotating about Jupiter. And there were
more discoveries via the new telescope: the
appearance of bumps next to the planet
Saturn (Galileo thought they were
companion stars; the "stars" were actually
the edges of Saturn's rings), spots on the
Sun's surface (though others had actually
seen the spots before), and seeing Venus
change from a full disk to a sliver of light. .
This, along with observing the phases of
Venus, provided support for the Copernican
heliocentric model of the universe over
ptolemys geocentric model.
Galileo Galilei published his findings on
astronomy in a small book titled The starry
Messenger. He wrote Dialogue on the two
Great Systems of the world this book talked
about the Copernican system.
Unfortunately, the book turned out to be
biased in favor of heliocentrism and the
Pope did not appreciate the perceived
public ridicule. Galileo was ordered to stand
trial of suspension of heresy in 1633.
Others:
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Galileo came up with rudimentary
thermometer which, for the first time,
allowed temperature variations to be
measured and an ingenious device to raise
water from aquifers found no market.
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In 1596 with an invented military compass
that could be used to accurately aim
cannonballs.
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KNOW YOUR SOLAR SYSTEM
Mercury
The Fastest-Moving Planet
Mercury was first spotted by Italian
astronomer Galileo in 1610. Mercury is the
nearest to sun and fastest moving Planet
in the Solar System. Until 1960s
astronomers believed that Mercury rotated
once every 88 Earth days, and took the
same time to go around the sun. But if
Mercury did this, one side of the planet
would always face the sun and the other
side would always be dark. However, radar
studies conducted in 1965 showed that the
planet rotates once in about 59 (58.646)
Earth-days a rotation but it moves around
the sun faster than any other planet about
48 km per second (30 miles). Some people
call mercury The messenger of Gods as
it guards all secrets.
Mercury has an Elliptical Orbit (Oval
shaped). At perihelion (Its closest point) it is
about 46 million kilometer and from aphelion
(its farthest point) it is 70 million kilometer
from the sun. Mercury is about 77.3 million
km (48 million miles) from Earth at itsclosest approach. Mercury is not easily
seen from Earth due to its small angular
separation of 27 from the Sun (less than
the angle made by the hand of the clock at
1 o clock). If one could stand on the
scorching surface of Mercury when it is at
its closest approach, the Sun would appear
almost three times as large as it does when
viewed from Earth.
As mercury is very close to Sun, one can
observe this planet from the ground-based
telescope of earth only during the day when
scattered sunlight impedes clear views ofthe planet, or just before sunrise and after
sunset, when the light must pass through it
10 times as much as atmospheric
turbulence as when it is overhead.
Unfortunately the best earth based
telescope get a worse view of it than
humans get of the moon with naked eye
each night.
Mercury possesses a thin exosphere made
up of atoms blasted off its surface by the
solar wind and striking Meteoroids rather
than a atmosphere. Because of the planet's
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Mass: 3.30e23 kg (5.5% of Earth's)
Diameter: 4,878km (3,032 miles) at its equator
Temperature: 350 C during the day and 170 Cduring night
Average Distance: About 58 million km (36 millionmiles)
Period of Rotation: 58.6462 days.
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extreme surface temperature, the atoms
quickly escape into space. With the thin
exosphere, there has been no wind erosion
of the surface and meteorites do not burn
up due to friction as they do in other
planetary atmospheres. Mercury's surface
resembles that of Earth's Moon, scarred by
many impact craters resulting from
collisions with meteoroids and comets.
While there are areas of smooth terrain,
there are also lobe-shaped scarps or cliffs,
some hundreds of miles long and soaring
up to a mile high, formed by early
contraction of the crust. The Caloris Basin,
one of the largest features on Mercury, is
about 1,300 kilometers (800 miles) in
diameter. It was the result of an asteroid
impact on the planet's surface in the early
history of our solar system. Over the next
half-billion years, Mercury shrank in radius
about 1 to 2 kilometers (0.6 to 1.2 miles) as
the planet cooled after its formation. In
1991, astronomers using radar observations
showed that Mercury may have water ice at
its north and south poles inside deep craters
that are perpetually cold (below -212
degrees Celsius or -350 degrees
Fahrenheit). Falling comets or meteorites
might have brought ice to these regions ofMercury, or water vapor might have out
gassed from the interior and frozen out at
the poles.
Broadly Planet Mercury is made up of 3
layers1) Core
2) Rocky mantle
3) Fine Soil
Mercury has a big iron Core which makes
about 75% of whole planets diameter and
above the core is rocky mantle and crust
about 600 km thick. The surface is cratered
and like the moon it is covered in finesoil.Mercury's rolling, dust-covered hills have
been eroded from the constant
bombardment of meteorites.
Mercury is the only planet other than earth
which has magnetic field on it but because
of its closeness to the Sun, it does not have
atmospheric conditions to sustain life. Since
Pluto was reclassified as a dwarf planet in2006, Mercury is now the smallest planet in
our solar system.
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MATHS CORNER
Vedic Mathematics
Nikhilam Navastascaramam Dasatah
In the last edition we discussed about the
evolution of Vedic mathematics and how
vedic mathematics simplifies our
mathematical calculations. We have learnt
Ekadhaikena Purvena sutra which made
squaring of the numbers ending with 5 a lot
simpler and time saving. In this edition well
discuss second sutra known as NikhilamNavastascaramam Dasatah. Nikhilam
Navastascaramam Dasatah means all
from 9 and the last from 10. By using this
sutra, multiplication of two numbers which
are near to bases 10, 100, 1000etc can
be simplified.
Now lets take an example to understand
how we can use Nikhilam
Navastascaramam Dasatah sutra in
multiplying and Division.
Nikhilam Multiplication:
It would be easy to understand nikhilam
multiplication by taking an example
Suppose we want to multiply 7 and 8
Step 1-
Here base is 10, since both the numbers
are near 10
Step 2-
Take the deviation of both the number from
10, by this we get two remainders one 3
(10-7) and other 2 (10-8).
Step3-
R.H.S of the answer is given by 2 * 3 = 6
The R.H.S. of the answer is the product ofthe deviations of the numbers. It shall
contain the number of digits equal to
number of zeroes in the base. If R.H.S.
contains less number of digits than the
number of zeros in the base, the remaining
digits are filled up by giving zero or zeroes
on the left side of the R.H.S. If the numbers
of digits are more than the number of
zeroes in the base, the excess digit or digits
are to be added to L.H.S of the answer
since base is 10, so
Step 4
LHS of the answer is 5
To find L.H.S of the answer, we can use any
one of the four ways depending on the
numbers
1) Subtract deviation 2 from the First
Number 7 i.e., (7-2) = 5.
SCIENCE FOR ALL Page 12
2) Subtract deviation 3 on the first row
from the second number i.e., (8 3)
= 5
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3) Subtract the base 10 from the sum
of the given numbers i.e., (7 + 8)
10 = 5
4) Subtract the sum of the two
deviations from the base i.e., 10 (3
+ 2) = 5
This gives 7 * 8 = 56
Lets take another example of two digit
number
Eg = 97 * 93
Step 1 -
Here base is 100 so two deviations are 3
(100-97) and 7 (100-93),
Step 2 -
By multiplying the deviations we will get
R.H.S - 3 * 7 =21
Step 3 -
To get L.H.S of the answer (we can use 1 or
2 method) 97-7 =90
Answer is 97 * 93 = 9021
Lets take another example of three digit
number:
Say, 750 * 995
Step 1-
Here base is 1000 so deviations are 250
(1000-750) and 5 (1000-995)
Step 2-
For R.H.S multiplying the two deviations
250 * 5 =1250
Step 3-
For L.H.S 750 5 =745(If the numbers of
digits are more than the number of zeroes in
the base, the excess digit or digits are to be
added to L.H.S of the answer since base is
10)
Therefore Answer is 746250
Nikhilam Division:
By nikhilam process of division, even
lengthier divisions do not involve no division
or no subtraction but only a few
multiplications of single digits with small
numbers and a simple addition. But nikhilam
division is applicable to only few cases.
Consider some two digit numbers
(dividends) and divisor 9
Say, 13 divided by 9
According to traditional method division will
be carried as follows
9) 13 (1
9
4
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Now By Nikhiliam Division, division will be
reduced merely in to multiplication and
addition
Step 1
Split each dividend into a left hand part for
Quotient and right hand part for remainder
by a slash
13 as 1 / 3
Step 2
Put the first digit of the dividend as left hand
part of the answer and the add same digit to
right hand part for the remainder
9) 1 / 3
1
1 / 4
By this answer is Q = 1, R = 4
Similar operation can be performed on
Eg = 43 / 9
9) 4 / 3
4
4 / 7
Q = 4, R = 7Now lets take examples of 3 & 4 digitnumbers
Eg = 106 / 9
9) 10 / 6
1 / 1
11 / 7
Q = 11, R = 7
Eg = 404 / 9
9) 40 / 4
4 / 4
44 / 8
Q = 44, R = 8
Eg = 1206 /9
9) 120 / 6
13 / 3
133 / 9
Simpler steps can be carried with more
than 4 digit number
In all the cases mentioned above, the
remainder is less than the divisor. Now
lets take few cases when remainder is
equal or greater than divisor
Eg = 36 / 9
9) 3 / 6 9) 24 / 6
3 2 / 6
3 / 9 26 / 12
(R is equal to divisor) (R is greater than divisor
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In such cases we proceed by re dividing the
remainder by 9 and carrying over this
quotient at quotient side
Now apply Nikhilam Navastascaramam
Dasatah to calculate multiplication and
division some other numbers and soon
youll master this technique9) 3 / 6 9) 24 / 6
/ 3 2 / 6
3 / 9 26 / 12
4 / 0 (After splitting)
26 / 1 / 2
/ 1
1 / 3
27 / 3
Q= 27, R = 3
SCIENCE FOR ALL Page 15
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HOW DOES THIS THING WORK?
DVD Technology
A Mark of clarityAs of the beginning of the twenty-first
century and with the advancement of
technology, Data, Audio & Video storage
medium has also turned from Magnetic
Tapes (Video Cassette) to DVDs. DVD
stands for Digital Versatile Disk or
Digital Video Disk. DVDs are Optical
high-density storage media for storing data,Audio & videos. This technology is
successor to Compact Disk popularly known
as CDs and replaced VHS tapes and Laser
Disk in entertainment industry. DVDs store
data by digital technology. A DVD of same
dimension as a CD can store five to ten
times as much data as one can store in CD.
It can store up to 17 Giga bytes of data. A
DVD provides much sharper images than a
VHS (Video Home System) videotape due
to the use of MPEG-2 compression (MPEG
stands for Moving Pictures Experts Group)
and Compression refers to the process of
condensing various audio and video signals
into less space while improving the quality.
In its most basic form, a DVD is one 0.02-
inch-thick (0.06-centimeter-thick) disc; at its
greatest capacity, a DVD is two such discs,
compressed together to create a double-
sided disc 0.04 inch (0.12 centimeter) thick.
It is circular wafer of plastic and metal
usually Aluminum, with a diameter of 4.75
inches (12 centimeter) and a hole in the
center. Data is converted in digital form
(Binary language ones and zeros) and this
digital data used in DVDs is encoded onto a
master disc. This disc is then used to create
copies of it. Each writable layer of a DVD
has a spiral track of data, track alwayscircles from the inside of the disc to the
outside. A laser (a device used to create a
narrow, intense beam of very bright light) is
use to burn small holes, called pits, into a
microscopic layer of metal. These pits
correspond to the binary ones and smooth
areas of the disc untouched by the laser,
called land, correspond to the binary
zeroes. Once the pits have been burnt, the
metal is coated with a protective,
transparent layer so that data will not get
destroyed. There are Dual layer DVDs also
available. Dual layer DVD can store upto
8.54 gigabytes per disk as compared with
4.7 gigabytes per single layer of disk. A
dual-layer disc differs from its usual DVD
counterpart by employing a second physical
layer within the disc itself.
SCIENCE FOR ALL Page 16
Now to read a DVD we require a DVD
player.
8/14/2019 Science for All July edition
17/22
SCIENC
A DVD
compon
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8/14/2019 Science for All July edition
18/22
SCIENCE FOR ALL Page 18
DVD and convert it to six separate analog
channels. This feature is not necessary if
you have a Dolby Digital receiver, which has
a digital input that carries all of the audio
information.
- DTS (Digital Theater Systems)
All DVD players are DTS compatible. They
pass the digital audio information on to the
receiver, which then decodes it.
96 kHz/24-bit DAC
This is the speed and accuracy of the
digital-to-analog converter (DAC), which
converts the audio information into an
analog signal. Most movie soundtracks are
encoded in this format, so this is really a
required feature, and most DVD players
should have at least a 96 kHz/24-bit DAC.
Simulated surround
If you are going to hook the DVD player up
to a TV or a stereo system with only two
speakers, a DVD player with simulated
surround processing will give you some
sense of surround sound without the extra
speakers.
Audio Decoders
Some DVD players should have built-in
Dolby Digital and DTS decoders; others rely
on the receiver to decode the audio tracks
on a disc.
Six-Channel analog outputs
These analog outputs are used for playing
multichannel Blu-ray, HD-DVD, SACD and
DVD-Audio discs if the player has a built-in
decoder for these formats. Six channel
analog outputs connect to corresponding
analog inputs on a receiver.
Picture enhancement
Progressive Scan, Video sampling
Number of DVDs DVD player can
change
8/14/2019 Science for All July edition
19/22
SCIENC
Cell is th
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http://en.wikipedia.org/wiki/Micrometrehttp://en.wikipedia.org/wiki/Micrometre8/14/2019 Science for All July edition
20/22
SCIENC
- N
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8/14/2019 Science for All July edition
21/22
SCIENCE FOR ALL Page 21
As plant prepare its own food, Plant cell
have one more component called
chloroplast
Chloroplast: The chloroplast allows plantsto harvest energy from sunlight.
Specialized pigments in the chloroplast
(including the common green pigment
chlorophyll) absorb sunlight and use this
energy to make food for plant.
Cells undergo a cell cycle, or cell-division
cycle, it is a series of events that take place
in a cell leading to its division and
duplication.
In cells without a nucleus (prokaryotes), the
cell cycle occurs by a process known as
binary fission. In cells with a nucleus
(eukaryotes), the cell cycle can be divided in
two brief periods: inter-phase during which
the cell grows, accumulating nutrients
needed for mitosis and duplicating its DNA
and the mitosis-phase, during which the cell
splits itself into two distinct cells, often
called "daughter cells". The cell-division
cycle is a vital process by which a single-
celled fertilized egg develops into a mature
organism, as well as the process by which
blood cells, hair, nail and some internal
organs are renewed.
8/14/2019 Science for All July edition
22/22
SCIENCE NEWS
Some Highlights of This Month
New Fluorescent Silicon
Nanoparticle Discovered
New Researchers in the Department of
Physics and Astronomy at the University
of Leicester have developed a new
synthesis method, which has led them
to the discovery of fluorescent silicon
nanoparticles and may ultimately help
track the uptake of drugs by the body'scells.
Breakthrough in development of tiny
Biological fuel cell
University of Georgia researchers have
developed a successful way to grow
molecular wire brushes that conduct
electrical charges, a first step indeveloping biological fuel cells that
could power pacemakers, cochlear
implants and prosthetic limbs.
New test can detect both genetic and
chromosomal abnormalities in
Embryos
The researchers based in the USA andthe UK have been able to prove that the
technique, known as genome-wide
karyomapping, is capable of not only
detecting diseases caused by a specific
gene mutation, in this case cystic
fibrosis, but that it would also capable of
detecting aneuploidy (an abnormal
number of any of the 23 pairs of
chromosome) at the same time. This is
the first time they have been able to
demonstrate that the test can work in
cells taken from embryos that have
already been diagnosed with the cystic
fibrosis gene mutation using
conventional pre implantation genetic
diagnosis (PGD).
After 18 years mission the solar
probe Ulysses retires
The solar probe Ulysses has circled the
sun for more than 18 yearsalmost as
long as the Greek hero Odysseus, also
called Ulysses, Ulysses will receive its
final transmission, as researchers say
the scientific findings sent home by the
failing spacecraft no longer justify the
missions costs. After shut- off, Ulysses
will continue to orbit the sun, becoming
in effect man- made Comet.
SCIENCE FOR ALL Page 22