Cement, Energy and Environment

ARRANGEMENT OF VEINS CONTROL CARBON, WATER INTAKE IN PLANTS Just like the circulatory system in humans, leaf veins are the lifeline of plants. The varied networks of veins in terms of shapes, sizes and thickness decide leaf economics. Scientists have shown vein patterns also control carbon and water absorption in plants. Benjamin Blonder of University of Arizona and his team analysed leaves of 2,500 plant species and prepared a mathematical model. The model shows spacing in the vein skeleton controls the amount of water the veins can supply, vein density controls the amount of C0 2 absorbed by the leaf, and loopy veins determine how resistant the leaf is to external damage. These traits vary between species, the researchers noted in the November issue of Ecology Letters. For instance, Blonder said, leaves of corn and rice have less venation spacing and high vein density. This suggests the plants have high water and carbon fluxes. The loopy venation of mango leaf protects in from tear. Leaves that have closely knit veins absorb more ' WORLDLY WISE . r I C0 2 • "But this does not mean we should plant trees with dense vein networks to save the planet," he added. The different patterns help the plant adjust to a variety of environment. For instance, plants in extreme climates have dense venation to enable theme retain C0 2 and water for long. Venation on fast growing plants are usually less dense and less loopy to carry water and C0 2 faster. This aids in high photosynthetic rate and quick food production. In India, most crops have short route vein networks as it means more water and carbon uptake and ultimately more food production, Blonder added. Courtesy: Down to Earth, December 16 - 31 , 2010, P.45. THE MAN AND HIS MACHINE In the late 1920s, a student at the University of Iowa wrote a dissertation that led to a breakthrough in calculating devices. The dissertation itself was not any great shakes. It was 1 0 pages of arcanH arithmetic. But it required Johan Atanasoff, the student, to perform months of calculations on a heavy metal desk calculator with a hundred typewriter-like keys designed to perform addition or subtraction multiplication and division were performed through repeated additions or subtractions. The laborious process led Atanasoff to think of making a friendlier calculating device. In The Man Who Invented The First Computer, Jane Smiley weaves the biography of the inventor with technological history of the times. As a child , Atanasoff memorized the manual of his father's Model T Ford and wired his family's home for electricity. He spoke often about nondecimal ways of counting. By the time he was in graduate school, Atanasoff, the son of Bulgarian immigrants, was known as the mad Russian. While working on his dissertation, Atanasoff realized that all scientific and engineering progress would be retarded unti l a breakthrough in methods of calculation. "I did not want to search and invent," he confessed, "but sadly I turned in that direction." By 1938, he had worked out the basic principles of his machine, and it was operational by mid-1940. Smiley notes that Atanasoff envisioned a machine much like the human brain, with regenerative memory. The device became known as the Atanasoff-Berry Computer. In his typical way, Atanasotf insisted his research assistant Clifford Berry share 58