Current affairs October 17, 2021

Pro drug and Molnupiravir

  • Antiviral drug Molnupiravir
  • Molnupiravir has significant promise.
  • But there are some concerns about how early and how mild the disease has to be for Molnupiravir to work
  • Molnupiravir is a pro-drug, which means that it needs to undergo processing in the body to become active.
  • It is metabolized to a ribonucleotide analog, which is essentially a sugar molecule linked to a molecule that resembles a nucleic acid.
  • Nucleic acids are needed to make RNA, and if Molnupiravir is used, the viral enzyme instead of using real cytidine or uridine uses a molecule that is generated by metabolism of Molnupiravir called NHC-TP.
  • The virus has a proof-reading mechanism but the viral exonuclease which is responsible for removing mistakes does not recognize NHC-TP as an error, so that when the viral RNA polymerase is making copies of RNA that contains Molnupiravir, then it randomly replaces cytidine or uridine.
  • This causes more mutations that can be survived by the virus or it becomes unable to replicate this is called lethal mutagenesis or error catastrophe

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 DLX1

  • Researchers at the Indian Institute of Technology (IIT), Kanpur, have discovered that a particular gene (DLX1) which plays an important role in the development of jaws, skeleton, and interneurons in the brain has an important role to play in the growth and development of prostate cancer.
  • The DLX1 protein is found at elevated levels in prostate cancer patients, the reason why the DLX1 protein has been used as a urine-based biomarker.
  • IIT Kanpur has found that the DLX1 protein, which is expressed at higher levels in the prostate cancer cells, has a huge role in the growth and development of the tumour and the spread of the cancer to other organs in the body (metastasis)

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Tobacco use

  • Archaeologists have uncovered evidence that hunter-gatherers in North America were using tobacco around 12,300 years ago 9,000 years earlier than was previously documented.
  • There is much debate on how and when tobacco plants were first domesticated.
  • Researchers have discovered the oldest direct evidence of tobacco use at a hunter-gatherer camp in Utah’s West Desert.

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Seagrass

  • Advantage seagrass Research by Dalhousie University and reported in Science found that seagrass meadows are much more genetically diverse and thus resilient in areas where otters are present.
  • Otters leave their trademark pits and craters on ground while digging for clams. The rough treatment of lush seagrass meadows appears to be producing a reproductive favor.

About Seagrasses

  • Seagrasses are underwater plants that evolved from land plants.
  • They are like terrestrial plants in that they have leaves, flowers, seeds, roots, and connective tissues, and they make their food through photosynthesis.
  • Seagrasses can reproduce sexually or asexually. They are flowering plants that produce seeds.

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Radio Waves

  • New class of object
  • University of Sydney astronomers have discovered unusual signals coming from the direction of the Milky Way’s center.
  • The radio waves fit no currently understood pattern of variable radio source and could suggest a new class of stellar object.
  • The light from the new signal oscillates in only one direction and that direction rotates with time.
  • The brightness also varies dramatically

About Radio waves

  • Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light. Radio waves have frequencies as high as 300 gigahertz to as low as 30 hertz.
  • At 300 GHz, the corresponding wavelength is 1 mm; at 30 Hz the corresponding wavelength is 10,000 km

Radio waves are a type of electromagnetic radiation best-known for their use in communication technologies, such as television, mobile phones and radios.

Oceans in Venus

  • While previous studies have suggested that Venus may have been a much more hospitable place in the past, with its own liquid water oceans, a recent study by astrophysicists led by the University of Geneva found that Venus is unlikely to have harbored any ocean anytime in the past.
  • The researchers simulated the climate of the Earth and Venus at the very beginning of their evolution, when the surface of the planets was still molten.
  • The high temperatures seen in Venus meant that any water would have been present in the form of steam.
  • This means the temperatures never got low enough for the water in its atmosphere to form raindrops that could fall on its surface.
  • Instead, water remained as a gas in the atmosphere, and oceans never formed.
  • “One of the main reasons for this is the clouds that form preferentially on the night side of the planet.
  • These clouds cause a very powerful greenhouse effect that prevented Venus from cooling as quickly as previously thought.

Malaria vaccine

  • On October 6, the World Health Organization made a historic announcement, endorsing the first-ever malaria vaccine, RTS,S, among children in sub-Saharan Africa, and in other regions with moderate-to-high Plasmodium falciparum malaria transmission.
  • It made its recommendations based on the results from a pilot programme administering the vaccine to children in Ghana, Kenya and Malawi.
  • Malaria is a life-threatening disease caused by micro-organisms that belong to the genus Plasmodium, and is transmitted by infected female Anopheles mosquitoes.
  • RTS,S/AS01 is a recombinant protein-based vaccine that acts against P. falciparum, believed to be the deadliest malaria parasite globally and the most prevalent in Africa.
  • Malaria is a major public health problem in India, endemic to many States, and involves multiple Plasmodium species, including P. falciparum.

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Frameworks

  • A few networked sheets, when stacked one over another, form a functional 2-D entity.
  • Because words like polymer do not do justice to this complex arrangement of atoms, such molecular networks are called frameworks.
  • Uses for these Covalent Organic Frameworks (COFs) take advantage of their stability, large surface area, controlled pore sizes, and tunable chemical environments.
  • Metal Organic frameworks (MOFs) are structured like COFs but have metals in complexes with organic entities.
  • The choice of metals is wide, from Beryllium to Zinc, though relatively abundant metals are preferred for economic and environmental reasons.
  • They offer great advantages: for gas storage, as in the case of hydrogen storage in fuel cells; in catalysis, where they replace very expensive metals; in sensors; and in drug-delivery anticancer and other drugs with severe side effects can be trapped in the porous confines of MOFs, to be released in small and steady doses.
  • Zeolites are highly porous, 3-D meshes of silica and alumina.
  • In nature, they occur where volcanic outflows have met water. Synthetic zeolites have proven to be a big and low-cost boon.
  • One biomedical device that has entered our lexicon during the pandemic is the oxygen concentrator.
  • This device has brought down the scale of oxygen purification from industrial-size plants to the volumes needed for a single person.

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