Science & Technology - 2 | Current Affairs & Hindu Analysis: Daily, Weekly & Monthly - UPSC PDF Download

Mud Crab Reovirus (MCRV)

About Mud Crab Reovirus 

• MCRV is a viral pathogen belongs to the family of ‘Reoviridae’. 
• It mainly affects the connective tissue of hepatopancreas, gills, and intestine. 
• It is also known as Sleeping Disease. 

Why It Is A Concerning Issue? 

• In Andhra Pradesh, total area under wild crab cultivation is around 25,000 acres and if crabs die because of MCRV, their cultivation will be badly affected. 
• Wild crabs are exported directly from Andhra Pradesh to the South-East Asia region and have a large market in Europe. International trade will also be badly affected. 
• Starting from 2019, about 60% of farming has been affected due to mass mortality in the state.

Lancet Report on Dementia
According to a Lancet report, the number of dementia cases in India is expected to almost double by 2050. 

Key Findings of This Report 

• The global dementia cases are expected to triple by 2050 and in India the cases will go up by 197%. 
• The study says that globally more women are affected by dementia than men and this pattern will continue till 2050. 

About Dementia 

• It is a syndrome that impairs the memory, thinking, reasoning and judgment of a person. 
• Though dementia predominantly found in older individuals, but it is not just associated with old age. It can also result from primary or secondary injury that affects the brain. 
• WHO categorises dementia into many forms. Alzheimer's disease is the most common form and may contribute to 60-70% of cases. 
• There is currently no treatment available to cure dementia. 
• Getting regular exercise, avoiding use of alcohol, eating a healthy diet, and maintaining healthy blood pressure, cholesterol levels can help lower the risk.

BrahMos

About BrahMos

• It is a medium-range ramjet supersonic cruise missile. 
• This missile is produced by BrahMos Aerospace which is an India-Russian Joint venture.The name BrahMos is formed from the Brahmaputra of India and the Moskva of Russia. 
• It is a two-stage (solid propellant engine in the first stage and liquid ramjet in second) missile. 
• It is a multiplatform missile i.e it can be launched from land, air, and sea and multi capability missile with pinpoint accuracy that works in both day and night irrespective of the weather conditions .
• The missile is capable of carrying a regular warhead as well as a nuclear warhead. 
• It operates on the "Fire and Forgets" principle, it does not require further guidance after launch. 
• It flies at a speed of 2.8 Mach or almost three times the speed of the sound. 
• The range of the missile was originally capped at 290 km as per obligations of the Missile Technology Control Regime (MTCR). 
• After entering this MTCR club in June 2016, India decided to increase the range capability of the missile which can be increased up to 450 to 600 km. 

About INS Visakhapatnam 

• INS Visakhapatnam is the first of the Visakhapatnam-class stealth guided-missile destroyers of the Indian Navy developed under Project-15B. Other Three Ships of Project 15B 
• 2^nd ship, Mormugao was launched in 2016, and is being readied for harbour trials. 
• 3^rd ship (Imphal) was launched in 2019, and is at an advanced stage of outfitting. 
• 4^th ship (Surat) is under block erection and will be launched within this current financial year (2022) 
• The ship is commissioned in November 2021. 
• It is indigenously designed by the Directorate of Naval Design, an in-house organization of the Indian Navy and manufactured by Mazagon Dock Shipbuilders Limited, Mumbai.

BRAHMOS

Man Portable Anti-Tank Guided Missile (MPATGM)

About MPATGM 

• MPATGM is third-generation anti-tank guided missile. 
• It is indigenously developed by DRDO in partnership with Indian defence contractor VEM Technologies Private Limited. 
• It can cover a minimum range of 200 to 300 m and a maximum range of 4 km. 
• It weighs around 14.5 kg to maintain man portability. It is integrated with thermal sight and works on fire and forget principle. 
• It is incorporated with state-of-the-art Miniaturized Infrared Imaging Seeker along with advanced avionics. 
• It is effective against both stationary and moving targets.

Country’s First Graphene Innovation Centre 

About The Centre 

• The Ministry of Electronics and IT has given approval for Rs 86.41 crore-project. Of the 86.41-crore, Union Government would provide Rs 49.18 crore and private business houses Rs 11.48 crore. The state government would provide the basic infrastructure for the project. The Centre would help attract investors to develop graphene products.
• The centre aims to be an anchor point to promote start-ups, commercial research & to bridge the gap between Graphene academic research and industrial application. 
• The centre will also develop the skilled manpower by anchoring Ph.D. and master students through Digital University, with an applied research focus in the areas of electronics product design, sensors, and energy applications

dApps 

• Decentralised applications or dApps are programmes that allow people to interact with one another without the need for third parties. For example, BitTorrent, Tor, and Popcorn Time are applications that run on computers that are part of a P2P network, whereby multiple participants are consuming content, feeding or seeding content, or simultaneously performing both functions. 
• They give the personal freedom to interact with a peer without being held accountable for it.
• They exist and run on a blockchain network or peer-to-peer (P2P) network of computers. DApps use smart contracts to complete the transaction between two anonymous parties
• These smart contracts are open-source pieces of code created by a decentralized authority, and no individual authority controls them. 
• dApps can be developed for a variety of purposes including gaming, finance, and social media.
• dApps are advantageous because, rather than relying on the competence and trustworthiness of third parties, they enforce contracts and agreements using solid code and a layer of computers. 
• Drawbacks include the potential inability to scale, challenges in developing a user interface, and difficulties in making code modifications. 

Ultra-long-period Magnetar 

• Scientists have detected an incredibly dense star and suspect it might be a type of exotic astrophysical object whose existence has been only hypothesised until now. 
• It was spotted using Murchison Widefield Array telescope in outback Western Australia. 
• It may be the first known example of what is called an ultra-long period magnetar.
  (i) A magnetar with a very long pulsation period is known as an ultra-long period magnetar
  (ii) For roughly 30 to 60 seconds, every 18.18 minutes, it pulses brightly, one of the most luminous objects in the low-frequency radio sky.
• It is located at about 4,000 light-years away.
• Objects turning on and off in the Universe aren’t new to astronomers. Astronomers call such objects as “transients”.

Second Earth Trojan Asteroid - 2020 XL5 

• Astronomers have confirmed the existence of a second Earth Trojan. 
• Trojan asteroids are those asteroids that share a common orbit with a planet in solar system.
• They can do so because they tend to be present at one of the stable Lagrange Points in the Earth-Sun system. 
• The trojan was detected in 2020 and is named 2020 XL5. 
• The asteroid was discovered by Pan-STARRS S1 telescope survey (Hawaii) and is estimated to be about 1.18 km wide. 
• It is a near-earth asteroid (NEO) that is expected to stay in orbit for the next 4,000 years before deviating away. 
• First known Earth Trojan asteroid was 2010 TK7, just about 0.3 km wide, and discovered in 2010. 
• Both earth trojans have been discovered in the L4 point. It is the 4th Earth – sun Lagrange point. A Lagrange point is a location in space where the combined gravitational forces of two large bodies, such as Earth and sun or Earth and moon, equal the centrifugal force felt by a much smaller third body. The interaction of the forces creates a point of equilibrium where a spacecraft may be "parked" to make observations 

Kavach 

• It is an anti-collision device (ACD) network.
• It is a Made-in-India technology designed to help Indian Railways achieve goal of zero accidents. 
• Kavach implementation will bring train movement to a halt automatically when it notices another train on the same line within a prescribed distance. 
• The technology uses microprocessors, global positioning system and radio communication. The anti – collision devices are mounted on the trains. The devices receive inputs from the satellite. They communicate with each other through modems. 

Chandrayaan-3 

• It is the third Moon mission of ISRO to explore the unchartered south pole of the celestial body. 
• It will be a mission repeat of Chandrayaan-2 but will only include a lander and rover similar to that of Chandrayaan-2. 
• It will communicate to earth via an orbiter from Chandrayaan 2. It will not have its own orbiter.
• The subsequent failure of the Vikram lander of Chandrayaan-2 led to the pursuit of another mission to demonstrate the landing capabilities needed for the Lunar Polar Exploration Mission proposed in partnership with Japan for 2024 

Thermobaric Weapon

• Thermobaric weapons are generally deployed as rockets or bomb.
• The thermobaric bomb involves a two-stage munition.
  (i) The first stage converts carbon-based fuel into minute metal particulates, which are discharged as an aerosol.
  (ii) The second part detonates the aerosol, converting it into a huge fireball and simultaneously creating an impactful shock wave. Inside this shock wave, a vacuum is created, which draws in (sucks) the nearby oxygen and exponentially enhances the severity of the explosion.
• They work by releasing fuel and explosive charges. Different fuels can be used, including toxic powdered metals and organic matter containing oxidant.
• The explosive charge disperses a large cloud of fuel which then ignites in contact with the oxygen in the surrounding air.
• They can penetrate bunkers and other underground locations, starving the occupants of oxygen.
• It is also known as an aerosol bomb, fuel-air explosive (FAE), or vacuum bomb.
• Vacuum bombs are not prohibited by any international law or agreement, but their use against civilian populations in built-up areas, schools or hospitals, could attract action under the Hague Conventions of 1899 and 1907
• It causes significantly greater devastation than a conventional bomb of comparable size.

Cluster Munitions

• A cluster munition means a “conventional munition that is designed to disperse or release explosive submunitions each weighing less than 20 kilograms, and includes those explosive submunitions”.
• Cluster munitions are non-precision weapons that are designed to injure or kill human beings indiscriminately over a large area, and to destroy vehicles and infrastructure such as runways, railway or power transmission lines.
• They can be dropped from an aircraft or launched in a projectile that spins in flight, scattering many bomblets as it travels.
• Many of these bomblets end up not exploding, but continue to lie on the ground, often partially or fully hidden and difficult to locate and remove, posing a threat to the civilian population for long after the fighting has ceased.

Daylight Harvesting Technology

About Daylight Harvesting Technology

• It is one of the most advanced techniques used in sustainable lighting designs for contemporary buildings.
• It is basically bringing natural sunlight inside the rooms
• It automatically adjusts the brightness of light in conjecture to the amount of light available in that space.
• The systems use a light level sensor, a photosensor, to detect the prevailing light level, luminance or brightness, in open-loop or closed-loop systems.
• Photosensors are used to adjust electric lighting based on the available daylight in the space.

Significance

• The solar energy spectrum has 45% energy as visible light and this can be used to harvest building illumination for about 9-11 hours a day.
• The technology used is completely indigenous, economically viable and easy to deploy and requires minimal maintenance over a long period of time.
• This can reduce the consumption of electric lighting energy by 70-80%, in addition to reducing the consumption of air-conditioning (cooling load).
• The daylight harvesting technology will be the next step towards a sustainable future.
• It will contribute to meet one of the commitments of the five nectars of “PANCHAMRIT” i.e., to make India a Net Zero emission country by 2070.

Noor 2 Satellite

About Noor 2 Satellite

• This is the Islamic Republic’s second military satellite launch.
• In April 2020, the first Noor military satellite was launched.
• Placing a second satellite in space would be a major advance for Iran's military.
• The satellite weighs 45 kg or less than 100 pounds.
• The three-stage Qased, or "Messenger", carrier launched the Noor 2, from Shahroud space port.
• Further details about the Noor-2 satellite were not released by the country's officials.

Newest Crater On Moon

• A leftover piece of a spacecraft flying through space, hit the surface of the moon, creating a new crater that may be around 65 feet wide.
• The piece of space was from the third-stage booster of Chang'e 5-T1, a lunar mission launched by the China in 2014.
• This is the first recorded unintentional case of space junk hitting the Moon.
• The speed, trajectory, and time of impact were calculated using earth-based telescope observations called Project Pluto (blog that tracks near-earth objects).

About Lunar Craters

• Lunar craters are impact craters on Earth's Moon.
• The Moon's surface has many craters, all of which were formed by impacts.
• International Astronomical Union currently recognizes 9,137 craters, of which 1,675 have been dated.
• The largest crater on the Moon is called South Pole-Aitken Basin.
• Craters on the moon are of a more permanent nature than those on earth. Moon’s lack of water, atmosphere, and tectonic plates, there is little erosion, and craters are found that exceed two billion years in age.

About Space Junk

• Space junk also called space debris, is any piece of machinery or debris left by humans in space.
• This material is orbiting Earth but is no longer functional.
• It can refer to big objects such as dead satellites and can also refer to smaller things, like bits of debris or paint flecks that have fallen off a rocket.
• There are approximately 23,000 pieces of debris larger than a softball orbiting the Earth.
• They travel at speeds up to 17,500 mph, fast enough for a relatively small piece of orbital debris to damage a satellite or a spacecraft.
• Kessler Syndrome: It says if there is too much space junk in orbit, it could result in a chain reaction where more and more objects will collide and create new space junk in the process, to the point where Earth's orbit becomes unusable – a Domino Effect

Solar Spicules

Researchers from India and the U.K. led by astronomers from the Indian Institute of Astrophysics, Bengaluru, have explained the origin of ‘spicules’ on the Sun Anomaly Of Sun’s Temperature

• The temperature at the core of the Sun is nearly 15 million degrees Celsius, while that at its surface layer, known as the photosphere, is merely 5,700 degrees C.
• The natural thing to expect is that still further outwards, in its atmosphere, known as the corona, the temperatures would be comparable to that at the surface (photosphere).
• However, the temperature of the corona is much higher.
• It starts increasing outside the photosphere, reaching a value of about one million degrees or more in the corona.

About Solar Spicules

• Solar spicules are jets of plasma, shooting out from the Sun’s outermost layer the chromosphere and making incursions into its atmosphere. These solar spicules emanate from the interface of the corona and the photosphere.
• A typical spicule may be 4,00012,000 kilometres long and 3001,100 kilometres wide.
• These are structures that are believed to transport momentum to the solar wind and to provide heat to the solar Corona
• It has been suspected that these spicules act as conduits through which mass and energy from the lower atmosphere bypass the photosphere and reach the corona.
• They are made of plasma – a mixture of positive ions and negatively charged electrons. The coronal plasma emits light in extreme ultraviolet.
• They move upwards with speeds between 15 and 110 km/s from the photosphere and last a few minutes each.
• In solar physics, a spicule, also known as a fibril or mottle.
• These jets rise and fall back under the influence of the Sun’s gravity, which is 20 to 30 times greater than Earth.
• Some jets are so energetic that they propel into the solar corona and beyond.
• The four ingredients that favour solar plasma jets are gravity, its fluid nature, strong quasi periodic triggers to eject plasma and Sun’s powerful magnetic field.
• Plasma is ejected from the sun’s surface as jet streams through periodic kicks of convection.

Gallium Nitride (GaN)

The Union Minister of State for Electronics & Information Technology visited the Gallium Nitride Ecosystem Enabling Centre and Incubator (GEECI) facility.

About Gallium nitride (GaN)

• It is a very hard, mechanically stable wide bandgap semiconductor as it has a hexagonal crystal structure.
• With high breakdown strength, fast switching speed, high thermal conductivity and low resistance, power devices based on GaN outperform silicon-based devices.
• Gallium nitride crystals can be grown on a variety of substrates, including sapphire, silicon carbide (SiC) and silicon (Si).
• GaN is used in the production of semiconductor power devices as well as RF components and light-emitting diodes (LEDs).
• GaN has demonstrated the capability to be the displacement technology for silicon semiconductors in power conversion, RF, and analog applications.
• GaN Technology is of strategic importance with its application to 5G, space and defence application. It offers a window of opportunity to play a key role in enabling e-vehicles and wireless communication.

About GEECI Facility

• It is situated at Indian Institute of Sciences (IISc), Bengaluru.
• The facility has been jointly set up by the Ministry of Electronics and Information Technology and IISc Bengaluru.
• It aimed at establishing GaN based Development Line Foundry facility, especially for RF and power applications, including strategic applications. 

World’s Largest Electric Cruise Ship

• The world’s largest electric cruise ship has made its maiden voyage, down the Yangtze River.
• The name of the ship is Yangtze River Three Gorges 1.
• It is a 100% electric cruise ship that has been developed and built in China.
• The cruise ship is powered by a massive 7,500 kilowatt-hour marine battery.
• The main purpose of this ship will be to ferry passengers who are going on a sightseeing tour on Yangtze River.
• On a single charge, the ship can travel around 100 kms thus saving about 530 metric tonnes of fuel.

Nipah virus infection (NiV)

• Scientists at Pune’s Indian Council of Medical Research were able to detect the presence of IgG antibodies against Nipah virus infection (NiV) in some bats.

About Antibody

• Antibody, also called immunoglobulin, a protective protein produced by the immune system in response to the presence of a foreign substance called antigen.
• Antibodies recognize and capture antigens to remove them from the body.

Different Types of Antibodies

• IgG - It is the main antibody in blood and it has a powerful ability to bind to bacteria and toxins, and thus it takes on an important role in the biological defense system.
• IgM - It is constructed of five units of basic Y-shaped structures and is mainly distributed to the blood.
  Produced first upon pathogen invasion by B cells, IgM has a key role in the initial immune system defense for protecting the body.
  • B cells, also known as B lymphocytes, are a type of white blood cell of the lymphocyte subtype. They function in the humoral immunity component of the adaptive immune system
• IgA - It is mainly present as monomers, but it forms dimers in secretions such as bowel fluid, nasal discharge, and saliva, to prevent bacterial invasion from a mucous membrane. It is also present in breast milk.
• IgD - It is present on the surface of B cells and it is reported to play a role in the induction of antibody production and the prevention of respiratory tract infections.
• IgE - It is believed that IgE was originally related to immunity reactions to parasites. By binding to mast cells, IgE is believed to be involved in allergies such as pollinosis.

Jupiter Like Protoplanet

• The Hubble Space Telescope has photographed a Jupiter-like proto-planet forming through a process that researchers have described as intense and violent.

Hubble Space Telescope

• The telescope has been built by NASA in 1990, along with contributions from the European Space Agency (ESA). It looks deep into space with cameras that can see the entire optical spectrum from infrared to ultraviolet.
• It is one of the largest space telescopes which can perform versatile missions. However, with the on-going construction of the Thirty Meter Telescope, HST will no longer with the largest light-vision telescope in the world

About Newly Forming Planet

• The newly formed planet captured by Hubble is called AB Aurigae b.
• It is embedded in a protoplanetary disk consisting of distinct spiral structures that revolve around a young star about 2 million years old.
• It is also about the same age as our solar system when planet formation was going on.
• It is 531 light years away from our Sun.
• It is probably about nine times the size of Jupiter and orbits its host star at a distance of 8.6 billion miles.

About Protoplanets

• These are small celestial objects that are the size of a moon or a bit bigger. They are small planets, like an even smaller version of a dwarf planet.
• These are a hypothetical eddy in a circling cloud of gas or dust that becomes a planet by condensation during the formation of the Solar System.
• Once they reach a certain size – around a kilometre – these objects are large enough to attract particles and other small objects with their gravity. They continue to get larger until they form protoplanets

Significance of This Finding

• This discovery supports a long-debated theory called “disk instability,” which tries to explain how planets similar to Jupiter are formed. In Disk Instability theory, matter slowly moves inwards in this disc as dust particles grow to centimetre-sized pebbles.
• This has led researchers to conclude that disc instability enabled the planet to form at such a great distance from its host star.
• The discovery paves the way for future studies into the chemical composition of protoplanetary discs.