About Carbon Dioxide (CO₂) Lasers

• The first CO₂ laser was developed by Indian-American scientist C.K.N. Patel.
• It is a four-level molecular gas laser that operates using vibrational energy states of CO₂ molecules.
• Highly efficient, producing high-power continuous or pulsed output.
• Structure: A CO₂ molecule consists of one carbon atom at the center and two oxygen atoms on either side. It vibrates in three independent modes:
  • Symmetric Stretching Mode: Oxygen atoms move simultaneously towards or away from the fixed carbon atom.
  • Bending Mode: Carbon and oxygen atoms vibrate perpendicular to the molecular axis.
  • Asymmetric Stretching Mode: Oxygen atoms move in one direction, while the carbon atom moves in the opposite direction.
• Principle of CO₂ Laser: The laser transition occurs between vibrational energy states of CO₂ molecules. Energy is transferred from excited nitrogen (N₂) molecules to CO₂, achieving the population inversion necessary for laser action.

Characteristics of CO₂ Laser

• Type: Molecular gas, four-level laser.
• Active medium: Gas mixture of CO₂, N₂, and He.
• Pumping Method: Electrical discharge.
• Optical Resonator: Concave mirrors.
• Power Output: Up to 10 kW.
• Nature of Output: Continuous wave (CW) or pulsed wave.
• Wavelength: 9.6 μm & 10.6 μm (Infrared region).

How does the Detection Work?

• Radioactive decay and ionisation: When a material undergoes radioactive decay, it emits charged particles (alpha, beta, or gamma rays) that ionize the surrounding air, creating plasma.
• Avalanche effect: The free electrons in plasma gain energy and collide with other atoms, releasing more electrons. This self-sustaining process is called avalanche breakdown and leads to a chain reaction of ionization.
• Laser characteristics: Researchers used a carbon-dioxide (CO₂) laser emitting long-wave infrared (LWIR) radiation at 9.2 micrometres. The longer wavelength reduces unwanted ionization and improves sensitivity.
• Detection mechanism: The laser accelerates seed electrons in the plasma, creating microplasma balls. These microplasmas generate a measurable optical backscatter that can be detected and analyzed.
• Fluorescence imaging: Used to analyze the plasma formation dynamics and understand the distribution of seed electrons.
• Mathematical model: Developed to predict backscatter signals based on plasma seed densities.
  • Validation: The model accurately reproduced experimental results, confirming the reliability of the detection technique.

Advancements in Detection Range

• Alpha particles: Successfully detected from 10 meters away (10x improvement over previous methods).
• Gamma rays (Cs-137): Could potentially be detected from 100 meters away by scaling up laser optics.

About Polar Orbit

• A Polar Orbit (PO) is a type of Low Earth Orbit (LEO) that ranges between 200 km to 1,000 km in altitude.
• Unlike equatorial orbits, satellites in a polar orbit travel from one pole to the other rather than from west to east.
• A deviation of up to 10 degrees from the exact North-South trajectory is still classified as a polar orbit.
• Significance:
  • Polar orbits allow satellites to cover the entire Earth's surface over time as the planet rotates below them.
  • These orbits are widely used for Earth observation, climate monitoring, and reconnaissance missions.
  • The Fram2 mission is the first human spaceflight to use this trajectory, making it a groundbreaking event in space exploration.

Why is this Mission Significant?

• First human spaceflight in a polar orbit: Unlike traditional missions that follow an equatorial orbit, this mission will orbit Earth from pole to pole.
• Expanding commercial spaceflight: Fram2 is SpaceX’s sixth private astronaut mission, further solidifying its dominance in the global private spaceflight sector.
  • It highlights the growing role of private players in space exploration, reducing reliance on government agencies like NASA.
• Reusable spacecraft innovation: The mission uses the Crew Dragon capsule, a reusable spacecraft developed by SpaceX with NASA funding.
  • SpaceX has now conducted 16 crewed missions using this capsule, proving the success of reusability in reducing spaceflight costs.

Why in the News?

• ISRO’s Earth observation satellite, CARTOSAT-3, captured high-resolution images of the destruction caused by the 7-magnitude earthquake that struck Myanmar on March 28, 2025.
• The post-disaster imagery (March 29) was compared with pre-event data (March 18) to assess the damage in Mandalay and Sagaing.

About CARTOSAT-3

• CARTOSAT-3 is a third-generation agile advanced Earth observation satellite developed by ISRO.
• It replaces the IRS (Indian Remote Sensing) series and has high-resolution imaging capabilities.
• Launched aboard the Polar Satellite Launch Vehicle (PSLV-C47).

Key Features

Applications of CARTOSAT-3

• National Security & Defense:
  • Military applications: Used for strategic surveillance, border security, and defense planning.
  • Previous use: Cartosat-2 aided in 2016 surgical strikes across the LoC and 2015 Myanmar-Manipur operations.
• Disaster Management & Urban Planning:
  • Assessing natural disasters: Earthquake, floods, and landslide monitoring.
  • Urban & Rural Infrastructure Planning: Road networks, water distribution, and land-use regulation.
  • Coastal Land Use & Regulation: Monitoring environmental changes along the coastline.
• Cartography & Remote Sensing:
  • High-Resolution Mapping for geospatial applications.
  • Detecting Natural & Man-Made Changes in geographical features.

Cartosat Satellite Series

• Cartosat-1 to 3: High-resolution Earth observation, urban and rural planning.
• RISAT Series: Radar-based imaging for cloud-penetrating surveillance.
• Oceansat Series: Monitors Ocean parameters, weather forecasting, and marine studies.
• INSAT & Megha Tropiques: Atmospheric studies and climate research.

About the Arctic Council

• The Arctic is governed by the Arctic Council, an intergovernmental body formed in 1996 through the Ottawa Declaration.
• Member States (8):
  • Canada, Denmark (Greenland), Finland, Iceland, Norway, Russia, Sweden, and the United States.
  • These countries control land territories and have rights over resources within their Exclusive Economic Zones (EEZs).
• Permanent participants: Six Indigenous groups representing Arctic inhabitants.
• Observers (Including India):
  • Thirteen countries (e.g., India, China, Japan, UK, France).
  • Thirteen intergovernmental organisations.
  • Twelve non-governmental organisations.
• All decisions require the consensus of the eight Arctic States and consultation with permanent participants.

The Northeast Passage

• The Northeast Passage (also called the Northern Sea Route) runs along Russia’s Arctic coastline, connecting Europe and Asia.
• Potential Advantages:
  • Shortens shipping distances between China and Europe by up to 8,000 km.
  • Reduces dependency on the Suez Canal, which faces security risks.
  • Economic boost for Russia, as it controls access to the route.

Why is the Arctic Gaining Strategic Importance?

• Natural resources: The Arctic holds 13% of the world’s undiscovered oil and 30% of untapped natural gas. Rich in rare earth elements, phosphates, and copper.
• New trade routes: The Northeast Passage (Russia) and the Northwest Passage (Canada) are emerging as alternatives to the Suez Canal, reducing travel distances by thousands of kilometers.
• Geopolitical interests: Russia, the US, and China are increasing military activities in the region, leading to rivalry and potential conflicts.
• Climate change impact: Ice melting is opening previously inaccessible areas for exploration and trade.
• Lack of Legal Safeguards: Unlike Antarctica, which is protected by international treaties, the Arctic is primarily governed by UNCLOS (United Nations Convention on the Law of the Sea). This allows territorial claims and military presence.

About Non-Alcoholic Fatty Liver Disease (NAFLD):

• NAFLD, now known as Metabolic dysfunction-associated steatotic liver disease (MASLD), is the term for a range of conditions caused by a build-up of fat in the liver.
• This buildup of fat is not caused by heavy alcohol use. When heavy alcohol use causes fat to build up in the liver, this condition is called alcohol-associated liver disease.
• Early-stage NAFLD does not usually cause any harm, but it can lead to serious liver damage, including cirrhosis, if it gets worse.
• Having high levels of fat in your liver is also associated with an increased risk of serious health problems, such as diabetes, high blood pressure and kidney disease.
• If you already have diabetes, NAFLD increases your chance of developing heart problems.
• Nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH) are types of NAFLD.
  • NASH is the severe form, which can cause cirrhosis and liver failure. It can also cause liver cancer.
• Who is more likely to develop NAFLD?
  • NAFLD is more common in people who have certain diseases and conditions, including obesity, and conditions that may be related to obesity, such as type 2 diabetes.
  • NAFLD can affect people of any age, including children.
• Treatment:
  • There's currently no specific medication for NAFLD.
  • Doctors recommend weight loss to treat
  • Weight loss can reduce fat, inflammation, and fibrosis in the liver.
  • Treatment may also be recommended for associated conditions (high blood pressure, diabetes, and cholesterol) or complications.

About Tribhuvandas Patel:

• Tribhuvandas Kishibhai Patel is an Indian independence activist, lawyer, and politician.
• A follower of Mahatma Gandhi, he is regarded as the father of the cooperative movement in India, most notably in the Kaira District Co-operative Milk Producers' Union in 1946, and the Anand Co-operative movement.
• He was born in 1903 to a farming family in Gujarat.
• He was very much influenced by the philosophy and principles of Mahatma Gandhi.
• He was totally involved in the various movements of Mahatma Gandhi, like civil disobedience, rural development, and the drive against untouchability, alcoholism,
• He was the President of Harijan Sevak Samiti from 1948 to 1983.
• In Nasik in 1930, he was jailed for the first time for the salt satyagraha.
• He was further imprisoned in Visapur in 1930 where he took an oath to dedicate his life for the benefit of the masses at large.
• In 1946, guided by the wisdom of Morarji Desai and inspired by Sardar Vallabhbhai Patel, Tribhuvandas formed the Kaira District Cooperative Milk Producers’ Union Ltd. (KDCMPUL) as a protest against the exploitation of local farmers by Polson Dairy.
• The basic approach adopted by Tribhuvandas Patel was first to establish milk cooperatives in the villages. These co-operatives were literally the “base” of the entire venture.
• He insisted that each village co-operative should be open to all milk producers in the village regardless of caste, creed, or community.
• He invited Dr. Verghese Kurien to KDCMPUL, who later spearheaded the White Revolution in India.
• He was instrumental in establishing the Gujarat Cooperative Milk Marketing Federation (GCMMF), National Dairy Development Board (NDDB), and Institute of Rural Management Anand (IRMA).
• During his lifetime he held various positions and received innumerable recognitions and awards for his outstanding leadership and social service. Some of these awards are:
  • Ramon Magsaysay Award from the Philippines in 1963 as a recognition towards his community leadership,
  • Padma Bhushan from the Government of India, 1964, towards Social Service.

About Abel Prize:

• The Abel Prize recognises pioneering scientific achievements in mathematics.
• It is named after Norwegian mathematician Niels Henrik Abel (1802-29), who in his short life made pioneering contributions to multiple fields.
• The prize was established by the Norwegian Parliament in 2002, on Abel’s 200th anniversary.
• The Abel Prize is awarded and administered by the Norwegian Academy of Science and Letters on behalf of the Norwegian government.
• The recipients are chosen by an expert committee appointed by the Academy under the advice of the International Mathematical Union (IMU) and the European Mathematical Society (EMS).
• First awarded in 2003, the Abel Prize is often considered to be an equivalent of the Nobel Prize, which does not have a category for mathematics. It has been modelled as such.
• The prize includes a monetary award of 7.5 million kroner (roughly USD720,000) and a glass plaque designed by Norwegian artist Henrik Haugan.

Abel Prize 2025:

• It was awarded to Japanese mathematician Masaki Kashiwara for his fundamental contributions to algebraic analysis and representation theory, in particular the development of the theory of D-modules and the discovery of crystal bases.
• His work has not only helped solve some hard problems that have been around for a long time but also opened new avenues for research by connecting areas that were not known to be connected before.
• For instance, Kashiwara discovered crystal bases, which allowed mathematicians to replace complex calculations with much simpler graphs of vertices connected by lines.

About NITI NCAER States Economic Forum Portal:

• It was developed by NITI Aayog, in collaboration with the National Council of Applied Economic Research (NCAER).
• It is a comprehensive repository of data on social, economic, and fiscal parameters, research reports, papers, and expert commentary on state finances for a period of about 30 years from 1990-91 to 2022-23.
• The portal has four main components, namely:
  • State Reports - summarising the macro and fiscal landscape of 28 Indian States, structured around indicators on demography, economic structure, and socio-economic and fiscal indicators.
  • Data Repository – offering direct access to the complete database categorised across five verticals, viz. Demography; Economic Structure; Fiscal; Health and Education.
  • State Fiscal and Economic Dashboard – showcasing graphical representations of key economic variables over time and provide quick access to raw data through a data appendix or additional information through summary tables.
  • Research and Commentary - draws on extensive research on State finances and critical aspects of fiscal policy and financial management at the State and national levels.
• The portal will facilitate an understanding of macro, fiscal, demographic, and socio-economic trends; easily accessible data and a user-friendly format; and will also address the ongoing need for consolidated sectoral data in one place.
• It will further help in benchmarking the data of each state against that of other States and the national figures.
• It will also provide a forum for policymakers, researchers, and others interested in alluding to the data for informed debates and discussions.
• The portal will serve as a comprehensive research hub, offering a wealth of data and analytical tools for in-depth research studies.
• By leveraging historical trends and real-time analytics, users will be able to track progress, identify emerging patterns, and formulate evidence-based policies for development.

About Exercise Tiger Triumph:

• It is an India-U.S. tri-service Humanitarian Assistance and Disaster Relief (HADR) Exercise.
• The exercise aims to enhance interoperability for conducting HADR operations and to formulate Standard Operating Procedures (SOPs) for establishing a Combined Coordination Centre (CCC).
• The Indian side would be represented by Indian Naval Ships Jalashwa, Gharial, Mumbai, and Shakti, along with integral helicopters and landing crafts embarked, Long Range Maritime Patrol Aircraft P8I, army troops from 91 Infantry Brigade and 12 Mechanical Infantry Battalion, Air Force C-130 Aircraft, and MI-17 Helicopters, along with the Rapid Action Medical Team (RAMT).
• The US side would be represented by US navy ships Comstock and Ralph Johnson, with troops of the US Marine Division embarked.
• Participants from both sides would also engage in training visits, subject matter expert exchanges, sports events, and social interactions.

About Alzheimer’s

• Alzheimer’s disease is a progressive neurodegenerative disorder that primarily affects memory, thinking, and reasoning abilities.
• It is the most common cause of dementia, accounting for 60-80% of all dementia cases
• The disease disrupts communication between brain cells, leading to a decline in cognitive and functional abilities.

What is Early-Onset Alzheimer’s?

• Most cases of Alzheimer’s occur in individuals aged 65 or older, but around 5-10% of cases develop before this age—this is called Early-Onset Alzheimer’s Disease (EOAD).
• Unlike late-onset Alzheimer’s, EOAD progresses more rapidly and often affects people in their prime working years, making it particularly devastating.
• Genetic factors play a crucial role in early-onset cases, with mutations in three specific genes—APP, PSEN1, and PSEN2—linked to increased risk.
• The Role of Amyloid Beta and Plaque Formation: The buildup of amyloid beta proteins in the brain leads to the formation of amyloid plaques, a hallmark of Alzheimer’s disease.
  • These plaques disrupt neural communication, trigger inflammation, and eventually lead to brain cell death.
  • Amyloid-targeting therapies aim to reduce these plaques, potentially slowing disease progression.

Gantenerumab

• Gantenerumab is an experimental drug that was initially discontinued but has now shown promise in new clinical trials.
• The latest trial focused on patients with genetic mutations known to cause early-onset Alzheimer’s.
• It was a randomized, placebo-controlled study, tracking disease progression using brain imaging and blood biomarkers.
• Results showed a significant reduction in amyloid plaque buildup, suggesting the drug may slow cognitive decline.

How does Gantenerumab Work?

• It is a monoclonal antibody, meaning it is lab-engineered to specifically target amyloid beta proteins.
• Once attached to amyloid plaques, it signals the immune system to break them down and remove them from the brain.
• The drug activates microglial cells, which act as the brain’s primary immune defenders, to clear toxic proteins more efficiently.
• A major challenge in treating neurological diseases is the blood-brain barrier, which blocks many drugs from reaching the brain.
• Gantenerumab can cross this barrier, making it more effective than some previous Alzheimer’s treatments.