Concepts in Science Technology YouTube Lecture Handouts Part 1

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20 Key GS Concepts in Science & Technology: Most Important “In News” Topic!

Science and Technology Key Concepts

Einstein Chwolson Ring

  • Gravity bends space
  • Light will follow curvature of space (similar to lens bending the light)

AMOLED Display

  • Active-matrix organic light-emitting diode
  • Used in mobile devices and televisions
  • OLED - thin-film-display technology - organic compounds
  • Low-power, low-cost and large-size applications
  • Generate light (luminescence) upon electrical activation that have been deposited or integrated onto a thin-film-transistor (TFT) array - series of switches to control the current flowing to each individual pixel

Light – Fidelity (LI-Fi)

  • Uses light waves rather RF to carry data
  • LED bulb functions as a router & is connected to the Internet
  • Unlicensed and free to use
  • High data speed due to low interference
  • Double benefit of access to light & internet
  • Doesn՚t interfere with electronic circuitry
  • Works under water
  • Data density 1000 times of Wi-Fi
  • Internet data flows in via device into bulb & is carried by light waves
  • Light waves falls on dongle connected to the computer

Low Temperature Thermal Desalination (LTTD)

  • When there is difference in temperature at different sea levels
  • If pressure is less, water evaporates at less than its normal temperature
  • Surface temperature of sea water is warmer than deep sea water
  • Surface water is collected & vacuum is created over it to evaporate
  • When evaporated vapor passes over cold water it gets condensed & water is distilled
  • Less ecological and environmental cost


  • Find arrangement of atoms in the crystalline solids
  • 2012: UN recognized importance of science of crystallography
  • 2014: International Year of Crystallography
  • X-ray crystallography used to determine structure of large biomolecules such as proteins
  • Uses X-ray, neutron, and electron diffraction techniques to identify and characterize solid materials


  • Spin transport electronics or spin electronics or Flextronics
  • Emerging technology uses intrinsic electron spin and associated magnetic moment along with fundamental electronic charge
  • Spins are manipulated by magnetic & electrical fields


  • High Efficiency Video Coding
  • Video compression standard
  • Successor to H. 264/MPEG-4 AVC (Advanced Video Coding)
  • First version completed and published in early 2013
  • Second version completed and published in 2014
  • 2nd version - supporting enhanced video formats, scalable coding extensions, and multi-view extensions

Micro Plastics

  • Small plastic particles in the environment
  • Smaller than 1 mm or 5 mm
  • Common use of 333 μm mesh neuston nets for field sampling (sample water volume) .
  • However, scientifically, their integral impact on wildlife and human health is not well established.

Doppler Radar

  • In News: 6th Doppler radar on East Coast
  • Other locations on East Coast: Chennai, Kolkata, Machilipatanam, Visakhapatnam and Paradip
  • Eastern coast prone to cyclones & will boost weather forecasting system
  • Built by ISRO and BHEL
  • Doppler Principle: When source for signals and observer are in relative motion - change in frequency (wavelength) is observed by observer
  • When source and observer move closer, frequency increases


  • Eco-friendly batteries
  • Generate electricity by renewable source like Sugar, glucose etc.
  • Final products are not a waste
  • Non-flammable and non-toxic
  • Ability to instant recharge and long backup
Mechanism of Bio Battery

NPL Syncs Leap Second with Indian Time

  • National Physical Laboratory added leap second
  • To compensate slowdown of earth՚s rotation
  • Every day 2000th of second is less
  • Every 500 days, 1 second is added to international atomic time
  • If clocks not updated it can led to failure of military systems, aircraft collision and error in financial markets

Ferroelectric Liquid Crystal Device (FLCD)

  • New generation display device like LCD
  • Has Ferro dielectric liquid crystal – with electricity gets magnetized
  • Fast switching time
  • Low dot pitch which results in a high resolution
  • Greater viewing angle
  • Better picture and thinner interface
  • Cheaper to run on electricity


  • Uses properties of quantum dots to localize magnetic or electrical fields at very small scales
  • Used in high-density in formation storage, energy storage & LED
  • Magnetic nan odots for future information storage
  • Store over 100 times more data than today՚s hard drives
  • Tiny magnets which can switch polarity to represent a binary digit

Double Fertilization

  • In flowering plants (angiosperms)
  • Female gametophyte (mega gametophyte or embryo sac) joins with two male gametes (sperm)
Double Fertilization

Genome Sequencing

  • Laboratory process that determines complete DNA sequence of an organism՚s genome at a single time
  • Sequence organism՚s chromosomal DNA & DNA in mitochondria

Noise Net

  • Controlled air around aircraft is filled with acoustic noise
  • Makes area near aircraft much riskier for birds
  • Reduce number of birds near aircrafts by 80 %
  • Saves birds from collision


  • Genome editing tool
  • Faster, cheaper and more accurate
  • Simplest, versatile & most precise
  • 2 molecules that change into DNA
  • Enzyme Cas9 - pair of ‘molecular scissors’ - cut 2 strands of DNA at a specific location
  • guide RNA (gRNA) : RNA sequence within longer RNA scaffold. Scaffold binds and ‘guides’ Cas9 to the right part of the genome
Mutation Caused by the Repair


  • High-voltage direct current (HVDC)
  • Electric power transmission system
  • Power super highway & electrical super highway
  • Uses direct current (DC)
  • Less expensive & lower electrical losses

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