RSTV: SCIENCE MONITOR 10.10.2020

RSTV


2020 Nobel Prize in physics:

  • Ithas been awarded to Roger Penrose, Reinhard Genzel and Andrea Ghez for furthering the understanding of black holes.
  • Penrose: Discovered “that black hole formation is a robust prediction of the general theory of relativity.
  • Genzel and Ghez:Discovered a “supermassive compact object at the centre of our galaxy.” This is now known to be the Sagittarius A* supermassive black hole, which has a mass four million times that of the Sun and is confined to an area roughly the size of our Solar System.
  • Black holes:-
    • A black hole is formed when stars collapse and can be defined as a space in the universe with an escape velocity so strong that even light cannot escape it.
    • Escape velocity is the speed at which an object must travel to override a planet or an object’s gravitational force.
    • Since light cannot get out, black holes are invisible and can only be tracked with the help of a space telescope or other special tools.
    • Light cannot escape from blackholes because the gravity inside a black hole is very strong as a result of a lot of matter being squeezed into a small space.

2020 Nobel Prize in Physiology:

  • Americans Harvey J Alter and Charles M Rice, and British scientist Michael Houghton have been awarded the Nobel Prize for Medicine or Physiology for the discovery of the hepatitis C virus.
  • The trio’s work helped explain a major source of blood-borne hepatitis that couldn’t be explained by the hepatitis A and B viruses.
  • Thanks to their discovery, highly sensitive blood tests for the virus are now available and these have essentially eliminated post-transfusion hepatitis in many parts of the world, greatly improving global health.
  • Their discovery also allowed the rapid development of antiviral drugs directed at hepatitis C.
  • Hepatitis C;
    • It is a liver disease.
    • Caused by the hepatitis C virus (HCV): the virus can cause both acute and chronic hepatitis.
    • Hepatitis C is a major cause of liver cancer.
    • The hepatitis C virus is a bloodborne virus:the most common modes of infection are through exposure to small quantities of blood.
    • Antiviral medicines can cure more than 95% of persons with hepatitis C infection, thereby reducing the risk of death from cirrhosis and liver cancer, but access to diagnosis and treatment is low.
    • There is currently no effective vaccine against hepatitis C;however, research in this area is ongoing.
    • There are 5 main hepatitis viruses, referred to as types A, B, C, D and E.
    • Hepatitis A and E are typically caused by ingestion of contaminated food or water.
    • Hepatitis B, C and D usually occur as a result of parenteral contact with infected body fluids.

2020 Nobel Prize in Chemistry:

  • It is awarded for CRISPR/Cas9 ‘Genetic Scissors.
  • Emmanuelle Charpentier and American Jennifer Doudna share the prize for developing the CRISPR/Cas9 toolto edit the DNA of animals, plants and microorganisms with precision.
  • It is possibly the only time in the history of Nobel Prize that two women have been declared the sole winners.
  • CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats):
    • It locates the specific area in the genetic sequence which has been diagnosed to be the cause of the problem, cuts it out, and replaces it with a new and correct sequence that no longer causes the problem.
    • significance of this technology:
    • It’s simple: Its simplicity has often been compared to the ‘Cut-Copy-Paste’ mechanism in any word processor (or probably, the equally common ‘Find-Replace’ mechanism).
    • Potential applications: Its uses can potentially transform human beings, and all other life forms. It can potentially eliminate genetic, and other, diseases, multiply agricultural production, correct deformities, and even open up the more contentious possibilities of producing ‘designer babies’, and bringing cosmetic perfection.
    • Efficient: Because the entire process is programmable, it has a remarkable efficiency, and has already brought almost miraculous results. Genetic sequences of disease-causing organisms can be altered to make them ineffective.
    • For Agriculture: Genes of plants can be edited to make them withstand pests, or improve their tolerance to drought or temperature.

Kodaikanal Solar Observatory:

  • The magnetic field of the Sun is unique in that, unlike many other celestial bodies, it reverses its polarity roughly every 11 years.
  • Regular observations of the Sun’s magnetic field begin in 1967, and, so far, we have data for the period from 1967 almost to the present, spanning the solar cycles 20-24.
  • Now, an Indo-Russian collaboration has added to this with a plot of the solar magnetic field from 1915 to 1965 (solar cycles 15-19).
  • Using a novel approach, they have calibrated and calculated the field using data from the archives of the Kodaikanal Solar Observatory of the Indian Institute of Astrophysics.
  • The present study makes the important contribution of building on this using the Kodaikanal Solar observatory data, and extending the magnetic field calculations for another fifty years approximately.
  • Understanding the magnetic field evolution in the past improves our understanding of the physics itself.
  • Therefore, understanding the magnetic field variations can contribute to our understanding of climate and space weather.
  • Kodaikanal Solar Observatory was established in 1899 and observations of the Sun from this observatory run over a hundred years, providing what is among the longest series of solar data. An important feature of these data is the multi-wavelength observations. The data consist of full disc spectral images of the Sun using the Ca II K and H-alpha lines. Both these lines image the atmospheric layer of the Sun known as the chromosphere.

Air Pollution effect on honeybees:

  • A new study lead by the National Centre for Biological Sciences (NCBS) researchers have revealed how air pollution may be depleting the health of honey bees in the wild.
  • Giant Asian Honey Bee produces over 80 per cent of the country’s honey and pollinates over 687 plants in Karnataka alone. An important pollinator, without the honey bees, India’s yearly mango export would lose over ₹65,000 Lacs.
  • The four-year study of over 1800 wild bees was led by Prof Shannon Olsson and published this week in the Proceedings of the National Academy of Sciences, USA.
  • Geetha G Thimme Gowda, a Postdoctoral scholar in Olsson’s lab at the institute, collected honey bees in and around Bengaluru. Geetha found that while a bee collected from the BLiSC campus on the northern and relatively low-polluted edge of the city carried a large amount of pollen on her body, a bee from Peenya, an industrial area, was covered in small particles containing lead, tungsten, arsenic, and a host of other toxic metals.
  • The researchers found that over 80 per cent of the bees that were collected from areas that are moderately or highly polluted died within 24 hours.
  • There are extreme gaps in our knowledge on the status of our wild pollinators in India. This study is a very important step in addressing this pressing concern.
  • Bees are important pollinators in our landscapes, and this study clearly shows how pollution adversely affects the health of bees.