Dr Rajiv Desai
An Educational Blog
HUMAN EVOLUTION
HUMAN EVOLUTION: _ Figure below shows conservator Effie Verveniotou and human origins researcher Dr Louise Humphrey examine the oldest nearly complete modern human skeleton ever found in Britain before it goes on display in the gallery. Cheddar Man is a human male fossil found in Gough’s Cave in Cheddar Gorge, Somerset, England. Excavated in 1903, Cheddar Man is Britain’s oldest complete human skeleton. Cheddar Man lived around 10,000 years ago. Analysis of his nuclear DNA indicates that he was a typical member of the western European population at the time, with lactose intolerance, dark skin, blue eyes, and dark curly or wavy hair. ________ Prologue: Recently, minister of state for human resource development of India said that the Darwinian theory of evolution was scientifically wrong and should not be taught in Indian institutions. Many scientists and students signed a petition calling upon him to withdraw his remarks. Three science academies […]
HOLOGRAM
HOLOGRAM: _____ Typical laser-lit transmission hologram ____ Prologue: Suppose you want to take a photograph of an apple. You hold a camera in front of it and, when you press the shutter button to take your picture, the camera lens opens briefly and lets light through to hit the film (in an old-fashioned camera) or the light-sensitive CCD chip (in a digital camera). All the light traveling from the apple comes from a single direction and enters a single lens, so the camera can record only a two-dimensional pattern of light, dark, and color. To be more accurate camera records wave length (color) and intensity (amplitude) of light waves. If you move your head slightly, the photograph remains same i.e. it is two dimensional. The physical world around us is three-dimensional (3D), yet traditional display devices can show only two-dimensional (2D) flat images that lack depth (i.e., the third dimension) […]
3D PRINTING
3D Printing: ____ In reality 3D printing is quite slow as compared to the figure above! ____ Prologue: The First Industrial Revolution took place from the 18th to 19th centuries in Europe and America. It involved iron and textile industries, along with the development of the steam engine. The Second Industrial Revolution took place between 1870 and 1914, just before World War I and technological advances during this period included the telephone, light bulb, phonograph and the internal combustion engine. The Third Industrial Revolution, or the Digital Revolution, started in 1980s which refers to the advancement of technology from analog electronic and mechanical devices to the digital technology available today. Advancements during the Third Industrial Revolution include the personal computer, the internet, and information and communications technology (ICT). The Fourth Industrial Revolution builds on the Digital Revolution, representing new ways in which technology becomes embedded within societies and even […]
DIGITAL TRANSACTION
Digital transaction: ___ ____ Prologue: History of banking dates back to 2000 B.C. Archaeologists believe that depositing and lending have always been human way of business and economy during renowned Roman, Chinese, and Indian empires. In fact, if we really think about it, there can actually be no trusted way of keeping earned money safe to be used when required other than a trusted group that also provides interest on such deposits. From that time banks and their ways have evolved tremendously. Computing revolution has been the biggest step forward here. For what was confined to signatures and psychical presence, has now been replaced by plastic money and virtual presence. John Shepherd-Barron, the Scotsman is credited with inventing the world’s first automated cash machine. Shepherd-Barron said once that he came up with the idea of the cash machines after being locked out of his bank. Plastic bank cards had not […]
ARE ORDINARY PEOPLE BAD?
Are ordinary people bad? ________ _______ Let me start by giving 3 examples from India: _ _ Example-1 On August 10, 2016 Matibool is on his way home from an overnight shift as a watchman, carrying a cellphone in his hand as seen in the figure above. It is dawn in Delhi. Suddenly, a speeding three-wheeled tempo barrels down on him from behind, knocking him into the air. The driver gets out, sees Matibool’s crumpled body and decides against even approaching him. In a matter of seconds, the driver is back in the truck, and away he goes. As Matibool lay bleeding for an hour, men and women riding in 140 cars and 82 rickshaws would avoid his dying body. So would 181 bikers and 45 pedestrians. At one point, an emergency response van used by the Delhi police drives by. A cycle rickshaw passes his body and stops a […]
