A datum (plural datums or data) is a reference point from which measurements are made. In surveying and geodesy, a datum is a set of reference points on the Earth’s surface against which position measurements are made. Horizontal datums are used for describing a point on the Earth’s surface in latitude and longitude or another coordinate system. Vertical datums measure …

Very simply, a cyclone is a kind of storm, and a storm is air which is moving quickly from one place to another. A storm begins when a mass of warm, moist air from the equator meets a mass of cold, dry air from the northern hemisphere. The two masses of air will not mix instead they form a front, …

A collection of a urine sample, blood sample or other body fluid samples are cultured in medium and analysed with for sensitivity. A “C&S” is a diagnostic lab procedure used to identify the type of bacteria and to determine which antibiotics can successfully fight an infection. C&S is primarily used to find bacteria. The absence of bacteria does not mean …

Unless you are a meteorologist (a person who studies the weather), it is unlikely that you will know that this is, in fact, a coded description of the climate of the Mediterranean regions. Devised by a Russian meteorologist, Vladimir Koppen, in the early 20th century, the code (see below) is based mainly on temperature and rainfall and is now used …

It is the technique of using extreme rapid cooling to freeze tissues, thereby destroy them. Rapid cooling to temperature below freezing point produces irreversible cell damage and cell death occurs at -20 to -90 degree Celsius. Freezing produces white areas of necrosis. It is applied in the treatment of malignancies, vascular tumours and aggressive tumours.

Cotton Candy is a soft confection that is made from sugar that is heated and spun into slim threads that look like a mass of cotton. It was invented in 1897 by William Morrison and John C Wharton, candy-makers from Nashville, Tennessee.

This is short for coronary thrombosis, which is the medical term for heart attack, and it occurs when a branch of a coronary artery gets blocked, which stops oxygenated blood reaching the heart muscles, so affecting the operation of the heart.

A cogwheel train is a train fitted with one or more cogwheels, which mesh with the toothed rail-rack, running usually between the normal rails. The system, operating on rack and pinion arrangement, is used in regions where trains operate on steep heights within a short span of time. Most cogwheel railways are mountain railways, although a few are transit railways …

A chromophore is a group of atoms and electrons (or moiety) i.e. part of organic molecules responsible for its colour. It is an extended delocalised systems of electrons in a compound which gives its colour e.g. chlorophyll’s porphin ring, or an azo dyes benzene ring linked to N=N double bond. When a molecule absorbs certain wavelengths of visible light and …

A chemical bond is one in which atoms of different or same elements combine to become stable. There are two types of chemical bonds – electro-valent bond and co-valent bond. In an electro-valent bond, a metal donates an electron to a non-metal and forms the bond. Such bonds are very strong. A co-valent bond is formed between non-metals only. These …