The Jovian Planets

The planets outside the orbit of Mars are called as Jovian planets because their structure is similar to that of Jupiter. These are all gaseous bodies. They have ring systems around them and have large number of moons.
Jupiter is a very bright object in the sky. It can be easily seen with the naked eye. It is the largest and the most massive planet in the solar system. It has a very deep atmosphere, mainly of hydrogen and helium. Because of its large mass and size, Jupiter exerts a strong gravitational pull on other objects which pass by it. The next three planets Saturn, Uranus and Neptune are similar to Jupiter. Saturn has the most beautiful and visible rings. The last planet Pluto is so small that it cannot be observed from the earth and no space mission has been sent into it yet.

Electro Encephalogram(EEG)

Electro Encephalogram shortly called EEG is used to record the electrical activity of the brain. This electric al activity is measured in the form of electric potentials. This process is called as Electro Encephalography. By placing two electrodes on the scalp of the patient, and leading via suitable amplifier to a CRT or to a ink-writing device, a record of four different types of waves can be obtained. These waves are named as alpha, beta, delta and theta. They vary in their frequency. These waves give the characteristic activity of the brain, and that is useful for study of brain problems like tumors, cerebral palsy, etc.

Superconductors

In 1911, the Dutch physicist H.K.Onnes, studied the variation of resistance of metals with temperature. He tried to cool some metals to a few Kelvins and measured their resistance. He discovered that mercury’s electrical resistance was reduced to zero at 4.2K (-269 degree Celsius). It was found that many other metals show similar behavior at certain low temperatures. This temperature is called as critical temperature. Such metals which exhibit this property is called as superconductors. In superconductors current can be transmitted without loss of energy.
Since superconductors require cooling to extremely low temperatures which were found very difficult to achieve, everyday use of superconductors was found impractical. Therefore, efforts made to search compounds that have higher critical temperatures. If superconductors are discovered which has zero resistance at room temperature, it will indeed greatly revolutionize many of the electrical devices we use today.

Benefits of Going Green

Trees can add value to your home, help cool your home and neighborhood break the cold winds to lower your heating costs, and provide food for wildlife.

TENTATIVE VALUE OF LONG LIFE TREE

• Generates oxygen worth Rs.8.6 lakhs
• Greatest Air pollution control worth Rs.10.5 lakhs
• Recycles fertility and soil erosion control Rs.8.4 lakhs
• Creates shelter for birds and other animals worth Rs.5.3 lakhs
• Provides flowers, fruits, medicines and other goods worth Rs.4.3 lakhs

Grand Total Rs.32.0 lakhs

So, felling of one tree means a net loss of about Rs.32 Lakhs.Stop using your axe.Start growing trees.

PLANT AND SAVE TREES

Dialysis

Though Kidney failure is not common, but sometimes kidney infection, injury to kidneys or restricted blood flow to kidneys result in kidney damage and malfunctioning. In order to clean the blood of metabolic wastes and to maintain normal levels of water and mineral ions in body fluids, a matching kidney from another person can be transplanted. But this process is very complex and the success percentage is very low. Instead an artificial kidney can be used. This artificial kidney is called as Dialysis.

Principle of Dialysis: Blood is made to flow into the dialyzing machine made of long cellulose tubes coiled in a tank having a dialyzing solution. Waste substances diffuse out of the blood into the tank. The purified blood is pumped back into the patient.

Dr.S.Chandrasekhar

Dr.S.Chandrasekhar, a great Indian Astrophysicist, was born on 19^th October, 1910. He got his B.A. (Hons.) degree in physics from the presidency college, Madras. Dr.Chandrasekhar published his first scientific paper, “Compton scattering and the new statistics”, in the proceedings of the royal society at the age of 18. He obtained his Ph.D. degree in 1933 from Cambridge university. After several years of extensive hard work, Chandrasekhar proved that stars smaller than 1.44 times the solar mass end up as ‘White Dwarfs’. The limit 1.44 solar mass is known as ‘Chandrasekhar Limit’.

In 1937, Chandrasekhar joined the university of Chicago, U.S.A. and became professor in 1944. In the same year, he was elected a Fellow of the Royal Society of London. He was awarded the National Science Medal of the United States in 1966, the Padma vibushan from the Govt. of India in 1968, and Nobel prize form physics in 1983. A recent satellite launched by the U.S.A. to study X-ray radiations in space has been named ‘Chandra’ the name by which Chandrasekhar is popularly known. Chandrasekhar died on August 21,1995 at the age of 84.

Heredity and Variation

Heredity means continuity of features from one generation to another. Eggs laid by a sparrow hatch into sparrows, but never into any other bird. A dog reproduces to give birth to pups only. This is the essence of heredity. Hereditary information is present in the fertilized egg of zygote. The zygote develops into an organism of a particular type only. Asexual reproduction individuals belonging to a give line of descent. While in sexual reproduction, both similarity and variation are clearly observed even among the off springs. Thus Heredity is the resemblances among individuals related by descent or the transmission of traits from parents to the off springs.
The concept of Heredity is not new. Selective breeding of horses and cattle used to be done during the ancient civilization of Babylon and Assyria. Ancient Chinese writings mention about creating better varieties of paddy. Charkara(100 BC) , the ancient Indian medical practitioner is evident from the fact that he knew the factors that determine the sex of a child. But the scientific principles, which govern patterns of inheritance, were unknown till the experiments and findings of Gregor Johann Mendel. Thats why he is called as the father of genetics. Mendel factors, the carriers of hereditary information, are what we know today as “genes”, a term coined by Johanssen in 1909.