Science and Technology: November 2022 Current Affairs | Science & Technology for UPSC CSE PDF Download

Dengue

Context
According to a study, the ongoing spread of Dengue in India has been attributed to a late withdrawal of monsoon.

• Dengue transmission is closely associated with three key factors — rainfall, humidity and temperature — which dictate the geographies in which dengue spreads and the transmission rate.

What are the Highlights of the Study?

• In India, the number of months suitable for dengue transmission by Aedes aegypti mosquitoes has risen to 5.6 months each year.
• It accounts for a 1.69% increase between 1951-1960 and 2012-2021.
• The study projected “expansion of Aedes aegypti in the hot arid regions of the Thar Desert and Aedes albopictus in cold upper Himalayas as a result of future climatic changes.
• Dengue spreads through the bite of two mosquitoes — Aedes aegypti and Aedes albopictus.
  • Currently, Aedes aegypti is prevalent in the southern peninsula, eastern coastline, north-eastern states and the northern plains.
  • Aedes albopictus dominates the eastern and western coastlines, north-eastern states and the lower Himalayas.

What is Dengue?

• About:
• Dengue is a mosquito-borne tropical disease caused by the dengue virus (Genus Flavivirus), transmitted by several species of female mosquito within the genus Aedes, principally Aedes aegypti.
• This mosquito also transmits chikungunya, yellow fever and Zika infection.
• There are 4 distinct, but closely related, serotypes (separate groups within a species of microorganisms that all share a similar characteristic) of the virus that cause dengue (DEN-1, DEN-2, DEN-3 and DEN-4).
• Symptoms:
  • Sudden high fever, severe headaches, pain behind the eyes, severe bone, joint, and muscle pain, etc.
• Diagnosis and Treatment:
  • Diagnosis of dengue infection is done with a blood test.
  • There is no specific medicine to treat dengue infection.
• Status of Dengue:
  • Incidence of dengue has grown dramatically around the world in recent decades, with a vast majority of cases under-reported, according to the World Health Organization (WHO).
  • WHO estimates 39 crore dengue virus infections per year, of which 9.6 crore show symptoms.
  • According to data shared by the National Center for Vector Borne Diseases Control, India recorded 63,280 dengue cases as of September, 2022
• Controlling Dengue Using Bacteria:
  • Recently researchers from the World Mosquito Program have used mosquitoes infected with Wolbachia bacteria to successfully control dengue in Indonesia.
• Method:
  • The scientists infected some mosquitoes with Wolbachia and then released them in the city where they bred with local mosquitoes, until nearly all mosquitoes in the area were carrying Wolbachia bacteria. This is called the Population Replacement Strategy.
  • At the end of 27 months, the researchers found that the incidence of dengue was 77% lower in areas where Wolbachia-infected mosquitoes had been released, as compared to areas without such deployments.
• Dengue Vaccine:
  • The dengue vaccine CYD-TDV or Dengvaxia was approved by the US Food & Drug Administration in 2019, the first dengue vaccine to get the regulatory nod in the US.
  • Dengvaxia is basically a live, attenuated dengue virus which has to be administered in people of ages 9 to 16 who have laboratory-confirmed previous dengue infection and who live in endemic areas.
  • Vaccine manufacturer Indian Immunologicals Limited (IIL) is developing India's first Dengue vaccine and has received permission for a Phase-1 trial.
  • The vaccine is being produced in collaboration with the National Institutes of Health in the US.

PSLV-C54

Context

Recently, ISRO’s PSLV-C54 successfully placed nine satellites which includes an Earth Observation Satellite (EOS-06) in multiple orbits.

• This is the 56th flight of the Polar Satellite Launch Vehicle (PSLV) and the 24th flight of the PSLV-XL version.

About the launch

The eight nano satellites includes:

• ISRO Nano Satellite-2 for Bhutan (INS-2B)
• Anand
• Astrocast (four satellites)
• Two Thybolt satellites.

EOS-6 is the Oceansat series’ third-generation satellite.

• EOS-06 is envisaged to observe ocean colour data, sea surface temperature and wind vector data to use in oceanography, climatic and meteorological applications.

Upcoming missions

• Aditya-L1: A coronagraphy spacecraft to study the solar atmosphere with a PSLV rocket. 
• NavIC: ISRO will also launch a navigation satellite for the country’s NavIC constellation.

Polar Satellite Launch Vehicle

• It is the third generation launch vehicle of India.
• It is the first Indian launch vehicle to be equipped with liquid stages.
• After its first successful launch in October 1994, PSLV emerged as the reliable and versatile workhorse launch vehicle of India.
• Difference: PSLV was developed to launch low-Earth Orbit satellites into polar and sun synchronous orbits whereas GSLV was developed to launch the heavier INSAT class of geosynchronous satellites into orbit.

Types of orbits

Geostationary orbit (GEO):

• Satellites in geostationary orbit (GEO) circle Earth above the equator from west to east following Earth’s rotation.
• This makes satellites in GEO appear to be ‘stationary’ over a fixed position.
• GEO is used by satellites that need to stay constantly above one particular place over Earth, such as telecommunication satellites.

Low Earth orbit (LEO):

• A low Earth orbit (LEO) is an orbit that is relatively close to Earth’s surface. 
• It is normally at an altitude of less than 1000 km but could be as low as 160 km above Earth.
• Unlike satellites in GEO that must always orbit along Earth’s equator, LEO satellites do not always have to follow a particular path around Earth in the same way their plane can be tilted.

Polar orbit and Sun-synchronous orbit (SSO):

• Sun-synchronous orbit (SSO) is a particular kind of polar orbit. 
• Satellites in SSO, traveling over the Polar Regions, are synchronous with the Sun. 
  • This means they are synchronized to always be in the same ‘fixed’ position relative to the Sun.
• This means that the satellite will always observe a point on the Earth as if constantly at the same time of the day.

India’s First Private Launch Vehicle

Context

Hyderabad-based Skyroot’s Vikram-S is all set to make its maiden flight from the country’s only spaceport in Sriharikota making it India’s first privately developed launch vehicle.

• The mission is code named ‘Prarambh’.

About the Prarambh mission

• It will mark the beginning of private sector launches in India.
  • The development of privately built rockets and satellites received a boost especially after the finance minister opened the space sector to private participation in 2020.
• Skyroot will be the first private company to launch its rocket.
• Other companies and missions:
  • Agnikul Cosmos tested its semi-cryogenic Agnilet engine.
  • ISRO’s Small Satellite Launch Vehicles (SSLV) is also likely to be manufactured and operated by private players soon.
• Private satellite missions launches by ISRO:
  • ISRO’s heaviest launch vehicle Mark III launched 36 OneWeb satellites (India’s Bharti is a stakeholder).
  • ISRO will be launching another fleet of 36 satellites for the company as well. 
  • The space agency has also launched at least four satellites made by students.

Vikram-S rocket

• It is a single-stage sub-orbital launch vehicle.
• It will carry three customer payloads in a sub-orbital flight. Among the three payloads is a 2.5kg satellite of another space startup, Space Kidz India, which has been built by students from India, the US and Indonesia. 
  • Sub-orbital flight are those vehicles which are travelling slower than the orbital velocity, meaning it is fast enough to reach outer space but not fast enough to stay in an orbit around the Earth.
  • It is roughly defined as a distance of more than 80 km from the Earth’s mean sea level.
  • Examples: the ones undertaken by Jeff Bezos and Richard Branson. 
• It will help test and validate technologies in the Vikram series space launch vehicles. 
  • The company is designing three Vikram rockets that will use various solid and cryogenic fuels to carry between 290 kg and 560 kg payloads to sun-synchronous polar orbits.
    • Vikram-I can carry 480 kilograms of payload to Low Earth Orbit. It will be powered by a Kalam-100 rocket. 
    • Vikram-II is equipped to lift off with 595 kilograms of cargo. 
    • Vikram-III can launch with 815 kg to 500 km Low Inclination Orbit.
  • In comparison, India’s PSLV can carry up to 1,750kg to such an orbit while the newly-developed small satellite launch vehicle meant for carrying smaller commercial satellites can carry up to 300 kg to sun-synchronous orbit.
• Tribute to Vikram Sarabhai
  • Skyroot's launch vehicles are named 'Vikram' as a tribute to the founder of the Indian space programme and renowned scientist Vikram Sarabhai.  

Significance of privatization of space sector

• Higher autonomy: private companies have a greater degree of autonomy in making decisions, which enables them to take up new projects.
• Quick decision making: There is quick decision making in private companies while the same process in a public enterprise would have to pass through a number of stages.
• Low costs: It has allowed companies like SpaceX, Blue Origin, etc. to cut their costs substantially and perform operations like launching a rocket to ISS at merely $57 million per seat as compared to $80 million per seat if aboard a Russian shuttle and $450 million each mission before NASA ended its space shuttle program. 
  • Making reusable landing rocket launchers, improvements in assembly lines and other such operations further ensure lower costs.
• Better employment opportunities: The growth in the space industry also provides employment to millions all over the world, and the rise in the number of private space companies promotes competition amongst them and encourages constant improvements and advancements.
• Creating widespread interest: The publicity of their operations, like live streaming launches, has sparked widespread interest in space exploration among the general public.

Cordy Gold Nanoparticles

Context: Bodoland University’s collaborative work on fungus-powered biosynthesised nanogold particles earns international patent.

About Cordy gold nanoparticles:

• Cordy gold nanoparticles (Cor-AuNPs), the outcome of a collaborative experiment by scientists from four Indian institutions, has earned an international patent from Germany.
• These nanoparticles, derived from the synthesis of the extracts of Cordyceps militaris and gold salts, could make drug delivery in the human body faster and surer.
• Cordyceps militaris is a high-value parasitic fungus.
• Gold salts are ionic chemical compounds of gold generally used in medicine.
• Penetration in the cells is more when the drug particles are smaller.
• Cordyceps militaris, called super mushroom for its tremendous medicinal properties, adds bioactive components to the synthesis of gold nanoparticles for better penetration.
• The wild Cordyceps mushroom is found in the eastern Himalayan belt.
• Biosynthesised nanogold particles indicate a new application of nanoparticles in the development of therapeutic drugs that can be delivered as ointments, tablets, capsules, and in other forms.

About Cordyceps militaris:

• Cordyceps militaris is a species of fungus in the family Cordycipitaceae, and the type species of the genus Cordyceps.
• It was originally described by Carl Linnaeus in 1753 as Clavaria militaris.
• Cordyceps militaris is entomopathogenic fungus, i.e., it parasitizes insects.
• It can be cultivated in a variety of media, including silkworm pupae, rice, and liquid nutrition.
• It is a potential harbourer of bio-metabolites for herbal drugs and there is evidence from ancient times for its applications for revitalization of various systems of the body.
• It contains a protein CMP18 which induces apoptosis in vitro via a mitochondrion-dependent pathway.

Xenotransplantation

Context
Genetically modified pig heart took longer than usual to beat for human receiver in the first-ever transplant of the gene-edited pig heart to human. The human recipient lived only for 61 days after the transplant.

• Prior attempts at such transplants have also failed.

What is Xenotransplantation?

• About:
  • Xenotransplantation involves the transplantation of nonhuman tissues or organs into human recipients.
  • In the recent heart transplant from pig to human, gene-editing was adopted to remove a sugar in its cells that’s responsible for that hyper-fast organ rejection.
  • Genome editing (also called gene editing) is a group of technologies that give scientists the ability to change an organism's Deoxy-Ribonucleic Acid (DNA).
  • One of the biggest obstacles to transplantation is organ rejection.
• Significance:
  • This development could bring us one step closer to solving the global organ shortage.
  • In India, patients need 25,000-30,000 liver transplants annually. But only about 1,500 end up receiving them.
  • Pigs are increasingly becoming popular candidates for organ transplantation.
  • Pigs offer advantages over primates for organ procurements, because they are easier to raise and achieve adult human size in six months.
  • The pig’s anatomical and physiological parameters are similar to that of humans, and the breeding of pigs in farms is widespread and cost-effective.

Indian Biological Data Centre

Context 
Union Minister of state for Science and Technology recently dedicated Indian Biological Data Centre (IBDC) to the nation.

About Indian Biological Data Centre

• The Indian Biological Data Centre is India’s first national repository for life science data.
• It will store all life science data generated from publicly funded research in the country.
• It operates with the assistance from the Department of Biotechnology (DBT).
• In long-term, IBDC seeks to become a major data repository for all life science data originating from India.
• It was established at the Regional Centre of Biotechnology (RCB) in Faridabad, Haryana.
• It has a data “disaster recovery” site in National Informatics Centre (NIC) in Bhubaneshwar.
• It has a data storage capacity of around 4 petabytes.
• It hosts the ‘Brahm’ High Performance Computing (HPC) facility.

The objectives of IBDC

• Provide IT platform for archiving of biological data originating from India.
• Develop standard operating procedures for storing and sharing of life sciences data based on FAIR (Findable, Accessible, Interoperable and Reusable) principle.
• Perform quality control and curation of data, maintain data backup and manage data life cycle.
• Develop web-based tools/APIs for data sharing or retrieval
• Organize training programme for analysing of large data and create awareness about the benefits of data sharing.

Significance

• At present, most Indian researchers depend on the European Molecular Biology Laboratory (EMBL) and National Centre for Biotechnology Information databases for storing biological data. ‘Indian Biological Data Bank’ will reduce our dependency on them.
• TB Bacteria sequences will help not only in understanding the spread of multi-drug and extremely drug resistant TB in the country, but also aid the search for targets for new therapies and vaccines.
• With genomes of humans, animals, and microbes present in the same database, it will also help researchers in studying zoonotic diseases, that is, diseases that jump from animals to humans.