14TH FEBRUARY CURRENT AFFAIRS

1. sDetailed genome on Malaria vector

News: Scientists have unveiled the detailed genome of the Asian malaria vector mosquito Anopheles stephensi.

Details:

  • Under the newly upgraded Anopheles stephensi genome, more than 3,000 genes that previously undetected genes have been unearthed.
  • The newly discovered genes are found to play key roles in the metabolism of ingested blood meal, reproduction and immunity against microbial parasites.
  • The discoveries also include 29 formerly undetected genes that play crucial roles in resistance to chemical insecticides.
  • The detailed genome of the malaria mosquito vector including new genes vital for the development of genetic control strategies of disease transmission would help malaria biologists in India and the rest of the world towards the goal of malaria elimination.
  • In order to engineer advanced forms of defence against malaria transmission, including targeted CRISPR and gene drive–based strategies, scientists require intricate knowledge of the genomes of vector mosquitoes.
  • CRISPR technology is a gene-editing tool which allows researchers to easily alter DNA sequences and modify gene function.
  • The newly discovered genes can also help address the issue of growing insecticide-resistant mutations in Asian and African An. stephensi populations.

2. Nanophotonics

News: Development of the mechanophotonics technique by researchers of University of Hyderabad.

Nanophotonics:

  • Nanophotonics or nano-opticsis the study of the behaviour of light on the nanometer scale, and of the interaction of nanometer-scale objects with light.
  • Small lasers have various desirable properties for optical communication including low threshold current (which helps power efficiency) and fast modulation (which means more data transmission). Small photodetectors tend to have a variety of desirable properties including low noise, high speed, and low voltage and power.
  • Nanophotonics has immense potential in fields ranging from biochemistry to electrical engineering. Nanophotonics would make it possible to go beyond current electronics and build up circuits driven entirely by photons (light).

Details about recent study:

  • Researchers from University of Hyderabad have developed a technique named “mechanophotonics” which has allowed them to move, slice, bend, and lift micron-sized waveguiding crystals using atomic force microscopy. Crystals are normally rigid, stiff structures.
  • Generally, millimetre- to centimetre-long crystals were bent using hand-held tweezers. This method lacks precision and control. Also, the crystals used were larger than what was required for miniaturisation.
  • The researchers have also been able to develop other crucial photonic elements like polymer microcavities or microresonators (light-trapping elements) using the same technique.
  • The researchers have been able to build an ‘organic photonic integrated circuit’ or OPIC using the technique.

Significance:

  • The ability to manipulate micron-sized crystals with precision and control would be very useful in the field of nanophotonics.
  • This technique can help achieve an unprecedented level of miniaturisation and pave the way to all-optical-technology such as pliable, wearable devices operated by light entirely.

3. Spotlight on dams after Chamoli disaster

News: A snow avalanche in a glacier in the Rishi Ganga catchment, triggered possibly by a landslide caused a flash flood in the Rishi Ganga river, a tributary of the Alaknanda in Chamoli district of Uttarakhand. The flash floods washed away a functional small hydroelectric project and destroyed the under-construction 520 MW Tapovan Vishnugad project of the NTPC on the Dhauli Ganga river.

Hydroelectricity in India:

  • In the 25 MW-plus category, there are projects with a combined capacity of 12,973.50 MW under installation. Of this, eight projects totalling 2,490 MW are in Uttarakhand.
  • The hydroelectric power qualifies as a renewable energy source and is cheaper compared to coal and gas plants due to lack of recurring costs.
  • The government has been offering incentives to make hydropower attractive. These include classification of large hydropower projects as Renewable Energy sources, creating a separate category for hydropower within Non-Solar Renewable Purchase Obligation, tariff rationalisation to bring down tariff, and budgetary support for putting up enabling infrastructure such as roads and bridges.

Why is it a cause of concern?

  • The recent incident has turned the spotlight on several ongoing dam-based hydroelectric projects in the State. Many experts have termed the development of large dam projects in the region unwise. The concerns being expressed about the slew of hydroelectric projects in Uttarakhand are based on the following grounds.
  • Uttarakhand is geologically unique. It being a part of the lesser Himalaya, it has numerous earth faults and hence it remains active in terms of deep movement of rock assemblages. It remains fragile from a geological point of view.
  • Along the Main Central Thrust (MCT), running east-west along the Himalaya, the Indian and Eurasian plates converge. The northward moving peninsular India presses the lesser Himalaya rock assemblages under the huge pile of the Great Himalayan rocks. As a result of the high geological stresses being induced in the region there is a weakening of rocks in the area.
  • In fact, many locations in a 50-km area within the MCT zone have witnessed several earthquakes of varying intensity, including those with magnitudes of over 5.
  • Despite the claim by dam builders that their structures can withstand even high-intensity earthquakes, most designs fail to incorporate the aspect of induced seismic effects of dams, especially in case of large dams.
  • Studies associated with Tehri dam has shown that there are concerns about induced seismic effects caused by the repeated filling and emptying of the reservoir, may deform the area around the dam making it vulnerable to earthquakes.
  • The region being mountainous with its steep slopes remains vulnerable to landslides induced with even low intensity earthquakes.
  • Moreover, the geology of mountains in many parts of Uttarakhand is such that the threat of landslides is high. Rocks here have been weakened by natural processes across time and are vulnerable to intense rainfall.
  • The human interference, in the form of house-building and road construction has only added to its vulnerability. The careless disposal of enormous debris from mining and construction projects has led to blocking of the flow path of rivers.

Should Uttarakhand worry about the threat of Climate Change?

  • The IPCC (Intergovernmental Panel on Climate Change)Special Report on the Ocean and Cryosphere in a Changing Climate found that in the Himalayan ranges, there could be variations in overall water availability due to melting of the glaciers and changes in monsoonal precipitation caused by changes to long-term climate.
  • The increased fluvial erosion aggravated by the erosion of mountain slopes would result in bringing debris and silt down the river courses, destroying physical structures, reducing dam life, and causing enormous losses. The global warming would increase the instability of glacial lakes in upper elevations.
  • Floods, avalanches and landslides are all forecast to increase in the region.
  • A strong earthquake could have a potentially serious fallout in terms of damage to life and property in the downstream regions.

Are expensive hydro-electric projects worth the investment today?

  • There are also questions being raised over the financial viability of the hydroelectric projects.
  • The hydroelectric projects are “highly capital-intensive”. They involve large investments and also the time for installation of large projects is large which further increases the costs of funding such projects.
  • Though hydropower has been reliable where suitable dam capacity exists, in places such as Uttarakhand, the net benefit of big dams is controversial because of the collateral and unquantified damage in terms of loss of lives, livelihoods and destruction of ecology.
  • Large dam projects involve large scale deforestation and destructionand involve massive and permanent alteration of the character and health of the hills.
  • Experts have advocated small low-impact dams of less than 5 megawatts as an alternative.
  • Additionally preventive and protective measuresare also needed to reduce the vulnerability to disasters.