Science & technology in everyday life

Agentic AI refers to systems that pursue a goal on their own, planning steps, using tools and adapting to results, rather than only answering a single prompt.

How it works

• A large language model serves as the reasoning core: it breaks the goal into sub-tasks, keeps a memory of context, calls tools such as APIs, browsers and code, checks results and iterates until the goal is met.
• Several agents may coordinate, each with a role, such as one that plans, one that executes and one that verifies.

Applications

• Business: customer-service agents that resolve a case end to end, coding agents, research assistants, supply-chain and IT operations.
• Public services: grievance handling that routes and follows up complaints, help with welfare applications, farm advisories in Indian languages, health triage and fraud detection.
• Illustration: an agent asked to arrange a journey checks availability, compares fares, fills the form and, with the user's approval, pays and files the ticket.

Advantages

• Productivity and round-the-clock service; personalised delivery at scale; capacity for complex, multi-step work that plain chatbots cannot complete.
• For India: scarce expertise is scaled, since one agent can serve lakhs of citizens in their own language, narrowing the gap between entitlement and delivery.

Risks

• Errors compound across steps; unintended actions with real-world effects; security threats such as prompt injection and misuse of credentials; privacy breaches through broad data access.

Challenges

• Accountability when an agent, not a person, acts; bias; job displacement; energy and compute needs; concentration in a few firms; regulation across borders.
• Governance response: human oversight for high-stakes actions and audit trails; India's AI Governance Guidelines (2025), which take a risk-based approach and bar unrestricted deployment of high-risk systems; the DPDP Act, 2023 for personal data; an AI Safety Institute.

Agentic AI should be deployed with humans in the loop, so that autonomy adds capacity without diluting accountability.

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CCUS captures carbon dioxide from large point sources such as power, steel and cement plants and either uses it in products or stores it permanently deep underground.

What CCUS is

• Capture: pre-combustion, post-combustion and oxy-fuel routes; direct air capture and bioenergy with CCS can even deliver net-negative emissions.
• Utilisation: urea, methanol, synthetic fuels, polymers, building materials and enhanced oil recovery.
• Storage: saline aquifers, depleted oil and gas fields and basalt formations.

Potential role in tackling climate change

• Hard-to-abate sectors: cuts process emissions in cement, steel, fertilisers and refineries, where renewables alone cannot reach.
• For India: coal will stay in the energy mix for decades; CCUS lets it be used while moving towards net zero by 2070 — NITI Aayog's 2022 study framed CCUS as the route to deep decarbonisation of such sectors.
• Co-benefits: a circular carbon economy, new industries and lower import bills when CO2 becomes feedstock.
• Limits: high cost and energy penalty, leakage risk, no CO2 pipelines, a low carbon price and the danger of prolonging fossil lock-in.
• Enablers: the carbon credit trading scheme, hub-and-cluster projects in industrial belts, mapping of storage sites and public funding for early projects (since then, the Union Budget 2026-27 announced ₹20,000 crore over five years).

CCUS complements, not replaces, renewables and efficiency: it is essential for residual industrial emissions, provided costs fall and storage is proven safe.

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Remote sensing gives a synoptic, repeated view of the earth; GIS stores, layers and analyses it; drones add on-demand, centimetre-level detail; and AI turns this flood of data into classification, prediction and choice.

Locational planning: where to put things

• Site selection: GIS suitability and network analysis for schools, hospitals, warehouses and industrial estates; AI weighs many criteria — demand, terrain, access, hazard — to rank candidate sites.
• Infrastructure corridors: PM Gati Shakti's GIS platform overlays roads, rail, utilities and forests so that new alignments avoid conflicts; AI optimises routes and cost.
• Utilities and renewables: irradiance and wind maps from satellites, plus drone surveys, locate solar parks, substations and pipelines.

Areal planning: regions, cities, resources

• Land records: under SVAMITVA (2020), drones map inhabited village land and GIS generates property cards, the base for panchayat development plans.
• Urban: GIS-based master plans, drone-derived 3D city models, AI detection of unauthorised construction and traffic modelling.
• Agriculture and water: satellite crop-area and yield estimation, watershed delineation, drone spraying and soil-moisture mapping.
• Forests and mining: change detection on satellite time series flags encroachment and illegal quarrying for enforcement.
• Disaster and environment: flood and landslide zonation, AI forest-fire alerts, rapid drone damage assessment after cyclones.

Conditions for effectiveness

• Data governance: privacy safeguards, the Drone Rules 2021 and the National Geospatial Policy 2022 that opens geospatial data.
• Capacity: trained planners in municipalities and panchayats, interoperable standards, and ground-truthing to check AI outputs against reality.

Together these tools turn planning from static maps into live, evidence-based decisions — provided skills and data governance keep pace.

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India's electronic toll collection runs on FASTag — a passive RFID sticker linked to a prepaid wallet or bank account and read by antennas at toll plazas under the National Electronic Toll Collection (NETC) system.

Advantages

• Shorter queues, fuel and time savings; cashless, traceable collection with less leakage and richer traffic data for planning.

Limitations

• Plazas and barriers remain; reader failures, blacklisted or cloned tags and double deductions cause disputes; a flat charge applies regardless of distance travelled.

Proposed changes

• GNSS-based tolling: on-board units and ANPR cameras allow barrier-less, multi-lane free flow with charges for the distance actually used.
• Rollout: after trials on the Bengaluru–Mysuru (NH-275) and Panipat–Hisar (NH-709) stretches, MoRTH decided in July 2024 to pilot GNSS tolling on selected highway sections alongside FASTag.

Potential hazards

• Privacy: continuous location tracking of every vehicle, with weak data-protection enforcement, invites surveillance and misuse.
• Technical: GNSS signal loss in tunnels and hills, spoofing, and cyber-attacks on the tolling backend.
• Enforcement and equity: evasion without barriers, disputes over deductions, and exclusion of users without devices or bank accounts.

A phased, hybrid rollout — NavIC-backed positioning, strict purpose limitation on data and clear grievance redress — can make tolling seamless without making it unsafe.

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Freshwater is a small share of Earth's water and most of it is locked in ice; WHO and UNICEF report that 1 in 4 people still lack safely managed drinking water, as pollution and climate change shrink the usable supply.

Alternative technologies

• Desalination, wastewater recycling, atmospheric water generation, managed aquifer recharge, rainwater harvesting, fog harvesting and solar stills — each suited to particular geographies.

Desalination (reverse osmosis)

• Merits: drought-proof supply for coastal cities, as at Chennai's Minjur and Nemmeli plants (100 MLD each); proven at scale.
• Demerits: energy-intensive and costly per litre; brine and chemicals harm marine life; membranes need imports and skilled upkeep.

Wastewater recycling

• Merits: tertiary treatment turns sewage into water for industry, farms and even drinking (Singapore's NEWater); cuts both demand and river pollution; Bengaluru sends treated water to fill Kolar's tanks.
• Demerits: high capital and energy cost, pathogen and micro-pollutant risks if standards slip, and public reluctance to accept reuse.

Atmospheric water generation

• Merits: draws potable water from humid air, useful for off-grid, coastal and disaster settings without pipelines.
• Demerits: heavy power use, low output and dependence on humidity make it unsuitable for arid regions at scale.

Cross-cutting lessons

• Technology works only with pricing, leak control, renewable power and reuse mandates that keep costs and emissions down.

No single technology suffices; a portfolio anchored in conservation and reuse, with desalination as a coastal backstop, offers the most sustainable way out.

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Artificial Intelligence refers to machines that learn from data to perform tasks needing human intelligence, such as recognising patterns, predicting and deciding; unlike fixed rule-based software, machine-learning and deep-learning models improve as they see more data.

AI in clinical diagnosis

• Imaging: models read X-rays, CT scans, retinal and pathology images to flag tuberculosis, cancers and diabetic retinopathy early, often before symptoms appear.
• Prediction: algorithms mine patient records to estimate the risk of complications and prompt timely intervention.
• Reach: decision support where specialists are scarce, faster triage and lower cost, a real gain for rural India.

Threat to privacy: yes, a real one

• Health data is the most sensitive personal data; the November 2022 attack on AIIMS Delhi's servers showed how exposed it is.
• Re-identification of anonymised datasets, commercial misuse by insurers or advertisers, and consent taken without understanding are live risks.
• Allied concerns: bias from unrepresentative training data, unclear accountability for a wrong diagnosis and over-reliance on the machine.

Safeguards

• The DPDP Act 2023 for consent and purpose limitation; consent-based sharing under the Ayushman Bharat Digital Mission; ICMR's ethical guidelines for AI in health; anonymisation, security audits and a doctor's final say.

AI should assist the clinician, not replace her, and be adopted only with firm consent, security and accountability norms.

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Transport is a major source of carbon dioxide and urban air pollution; electrification shifts emissions from millions of tailpipes to power plants that can be cleaned.

How EVs cut carbon emissions

• No tailpipe emissions: EVs release no CO2, NOx or particulates on the road.
• Efficiency: electric motors convert far more of their energy into motion, where combustion engines waste most of it as heat, so energy per kilometre and lifecycle emissions are usually lower even on a coal-heavy grid.
• Cleaner over time: as solar and wind grow in the power mix, every EV already on the road gets greener; smart charging and vehicle batteries can absorb surplus renewable power.
• Regenerative braking recovers energy that combustion vehicles lose.

Key benefits over combustion engines

• Economic: lower running and maintenance cost with fewer moving parts, and reduced dependence on imported crude oil, easing the import bill and strengthening energy security.
• Urban: cleaner air, less noise and better public health in cities.
• Industrial: a new value chain in batteries, motors and electronics, supported by PLI for advanced-chemistry cells and auto components, FAME-II purchase incentives, lower GST on EVs and state EV policies.

Caveats

• High upfront cost, patchy charging networks and range anxiety.
• Coal-heavy electricity limits the gain until the grid decarbonises.
• Dependence on imported battery materials such as lithium, cobalt and nickel, and the need for battery recycling to avoid a new waste stream.

EVs deliver real climate and health gains when paired with clean electricity, public charging and responsible battery recycling.

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Cellulose, a long chain of glucose units and the most abundant plant polymer, returns to the atmosphere through the carbon cycle, and microbes do most of the work.

Breaking down the polymer

• Fragmentation: earthworms, termites and other detritivores shred fallen leaves and wood; the smaller pieces expose far more surface to microbial attack.
• Enzymatic hydrolysis: fungi and bacteria secrete cellulase enzymes that cut the cellulose chains into cellobiose and then into glucose.

From glucose to carbon dioxide and water

• Aerobic respiration: in well-aerated soil and litter, microbes oxidise the glucose, releasing carbon dioxide, water and energy; this is the main route by which plant carbon returns to the air.

Other pathways and end products

• Anaerobic decay: in waterlogged soils, wetlands, paddy fields and animal guts, fermentation and methanogenesis yield organic acids, methane and carbon dioxide.
• Herbivores: ruminants and termites cannot digest cellulose themselves; gut microbes ferment it and the carbon leaves as carbon dioxide and methane.
• Humus: lignin-rich residues resist decay and form dark humus that holds water and nutrients in the soil.
• Fire and burial: fire oxidises litter rapidly to carbon dioxide and water, while plant matter buried away from oxygen can become peat and, over geological time, coal.

These processes close the carbon cycle and sustain soil fertility, though the methane released in wet conditions ties decomposition to climate change.

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Launched on 25 December 2021, the James Webb Space Telescope (JWST), led by NASA with the European and Canadian space agencies, is the most powerful space observatory built so far, designed to see the universe in infrared.

Unique features

• Mirror: a 6.5-metre segmented, gold-coated primary mirror of 18 hexagonal pieces, far larger than Hubble's 2.4 m, gathers much more light.
• Infrared vision: it observes mainly near- and mid-infrared light, so it sees through dust and detects very distant, red-shifted early galaxies invisible to Hubble, which works mostly in optical and ultraviolet light.
• Cold operation: a five-layer sunshield keeps the instruments very cold so their own heat does not swamp faint infrared signals.
• Location: it orbits the Sun-Earth L2 point about 1.5 million km away, where cold, stable conditions allow uninterrupted observation, unlike Hubble in low Earth orbit.

Key goals

• See the first stars and galaxies that formed after the Big Bang.
• Study how galaxies, stars and planetary systems form and evolve.
• Analyse exoplanet atmospheres for water and other signs of habitability.

Potential benefits

• Knowledge: a deeper understanding of cosmic origins and of whether life exists elsewhere.
• Technology: spin-offs in infrared detectors, precision optics and lightweight materials.
• Cooperation and inspiration: an international scientific partnership and a spur to science education.
• Caveat: it cannot be serviced like Hubble, and it came at high cost after long delays.

JWST extends humanity's view to the edge of the observable universe and, through its technology and inspiration, benefits science on Earth too.

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A vaccine trains the immune system to recognise a pathogen without causing the disease, so that on real exposure the body responds faster and harder.

Basic principle

• Exposure to a harmless form or part of a pathogen (the antigen) prompts adaptive immunity and leaves behind memory cells, so the body mounts a rapid secondary response on infection.
• Population effect: when enough people are immune, transmission falls and even the unvaccinated gain herd protection.

How vaccines work

• Antigen-presenting cells process the antigen and alert helper T cells.
• B cells make antibodies that neutralise the pathogen, while killer T cells destroy infected cells.
• Memory B and T cells persist for years; adjuvants strengthen the response and boosters renew waning immunity.
• Platforms: live attenuated, inactivated, subunit or protein, toxoid, viral vector, DNA and mRNA vaccines differ in how they present the antigen.

Indian approaches to COVID-19 vaccines

• Inactivated whole virion: Covaxin, developed indigenously by Bharat Biotech with ICMR and NIV Pune.
• Viral vector: Covishield, the Oxford-AstraZeneca chimpanzee-adenovirus vaccine, made under licence by the Serum Institute of India; Sputnik V, an adenovirus-vector vaccine, produced by Indian partners.
• DNA plasmid: ZyCoV-D (Zydus), a plasmid DNA vaccine.
• Protein subunit: Corbevax (Biological E), a recombinant protein-subunit vaccine.
• Later: mRNA and intranasal candidates followed, widening the toolkit.

A mix of indigenous and licensed platforms gave India scale and choice during the pandemic and left it with stronger vaccine-making capacity for the future.

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The S-400 Triumf is Russia's long-range surface-to-air missile system; India contracted five squadrons in October 2018 to shield its western and northern fronts.

What gives it the edge

• Layered reach: one system fires four missile types for different bands, the longest reaching about 400 km, so it covers short, medium and long-range threats together.
• Multi-role: it engages combat aircraft, cruise missiles, drones and tactical ballistic missiles through a single network of radars, command posts and launchers.
• Sensors: long-range surveillance and engagement radars track many targets at once.
• Mobility: road-mobile launchers and radars redeploy quickly, so they are hard to target pre-emptively.
• Against peers: Patriot has shorter reach and THAAD is built mainly for ballistic missiles; the S-400's mix of range and roles in one package is its distinction.

Testing the claim

• "Superior to every other system" is a claim, not a record: performance against stealth aircraft, saturation attacks and electronic warfare is untested in combat.
• No single system can seal the sky; for India the deal also carries CAATSA sanction risk and dependence on Russian supply.
• It works best layered with indigenous air and missile defence and an integrated radar network.

The S-400 is among the most capable long-range air-defence systems, but India's security lies in layering it with indigenous systems and networked sensors, not in any single purchase.

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Red and green LEDs had existed for decades, but only the blue LED of Akasaki, Amano and Nakamura made efficient white light possible, which is why the 2014 Nobel Prize in Physics treated it as an invention of greatest benefit to mankind.

Why blue completed the picture

• A blue LED coated with phosphor, or combined with red and green LEDs, produces white light; this is the basis of every LED lamp and backlit screen.

Impact on everyday life

• Energy and cost: LEDs convert far more of their electricity into light than incandescent bulbs and last many times longer, cutting bills, replacements and lighting's share of power demand.
• Ubiquity: home and street lighting, phone, television and computer screens, vehicle headlights, traffic signals and torches all run on LEDs.
• Access: low power needs let solar lamps light homes beyond the grid, replacing kerosene and extending study and work hours; the Nobel committee noted this promise for over 1.5 billion people without grid access.
• Health: blue-light phototherapy treats newborn jaundice.
• Environment: lower electricity demand means lower emissions, and LEDs contain no mercury, unlike CFLs.
• India: the UJALA scheme (January 2015) spread low-cost LED bulbs to households, cutting household bills.

Concerns

• Blue-rich light at night disturbs sleep, brighter cheap lighting adds to light pollution, and discarded LED electronics add to e-waste; standards and disposal norms are needed.

A small semiconductor invention lit homes and streets with a fraction of the energy and carried light to places the grid never reached; its next test is using it wisely.

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Nanotechnology is the engineering of matter at the scale of roughly 1 to 100 nanometres (a nanometre is a billionth of a metre), where materials show optical, chemical and biological properties they lack in bulk.

What nanotechnology is

• It builds particles, materials and devices atom by atom or molecule by molecule; at this scale surface area rises sharply and quantum effects appear, giving new strength, reactivity and conductivity.
• India's Nano Mission of the Department of Science and Technology (2007) funds research and infrastructure in the field.

Uses in the health sector

• Targeted drug delivery: nanoparticles and liposomes carry a drug to diseased tissue, as in cancer therapy, raising effect and cutting side effects.
• Diagnostics and imaging: nano-biosensors, quantum dots and contrast agents detect disease early; lab-on-chip devices enable low-cost point-of-care tests.
• Vaccines: lipid nanoparticles carry the mRNA in COVID-19 vaccines, showing nanotechnology serving public health at scale.
• Treatment and repair: nano-scaffolds for tissue engineering, nano-coatings for implants, and silver nanoparticles as antimicrobial agents in wound care.

Concerns

• Nanotoxicity and unknown long-term effects, accumulation in the body and environment, and thin regulation call for safety testing and clear norms.

Nanotechnology can make diagnosis earlier and treatment more precise, provided safety testing and regulation keep pace with the science.

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From the food on the plate and the vaccine in the arm to the phone in the hand, science and its technologies shape daily life, usually without being noticed.

Science in everyday life

• Health: vaccines, antibiotics and diagnostics have lengthened lives; clean water and sanitation rest on chemistry and microbiology.
• Connectivity and money: mobile phones, the internet and UPI payments run on semiconductors and satellites.
• Energy and home: electricity, LEDs, refrigeration and household appliances; weather forecasts and ISRO's remote-sensing services guide farmers, fishermen and disaster response.
• Mind and State: scientific temper, a fundamental duty under Article 51A(h), and evidence-based, data-driven governance.

Striking changes in agriculture

• Green Revolution: high-yielding dwarf wheat and rice, with fertiliser and assured irrigation, turned food deficit into self-sufficiency in foodgrains.
• Biotechnology and breeding: Bt cotton (2002), hybrids, tissue culture and improved livestock breeds; Operation Flood helped make India the largest milk producer.
• Precision and digital farming: drones, satellite crop and soil monitoring, soil health cards, weather advisories, e-NAM and mobile advisory apps.
• Water and inputs: drip and sprinkler irrigation, bio-fertilisers, integrated pest management, cold chains and climate-resilient seeds.
• The cost: soil and groundwater damage, pesticide residues, monoculture and biodiversity loss, and unequal access.

Science is woven into every part of life; in agriculture its next task is to move from raising yield alone to sustainable and shared gains.

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The pandemic showed how fast technology can be mobilised in a crisis: from genome sequencing and contact tracing to vaccines developed in under a year and public services delivered online.

Detection and surveillance

• Testing: RT-PCR and rapid antigen kits, pooled testing and genome sequencing tracked the virus and its variants; AI-aided reading of chest images supported diagnosis.
• Tracing: the Aarogya Setu contact-tracing app, GIS maps of containment zones, thermal screening, and drones for surveillance and public announcements.

Treatment and hospitals

• Telemedicine through eSanjeevani kept care going during lockdown; indigenous ventilators, PPE and testing kits were scaled up; robots and UV disinfection reduced staff exposure; trials tested plasma and repurposed drugs.

Vaccines

• Vaccines came in record time on mRNA, viral-vector and inactivated-virus platforms; India's Covishield and Covaxin were delivered through CoWIN, which handled registration, slots and certificates.

Continuity of life and welfare

• Work from home and video conferencing, online classes through DIKSHA and SWAYAM, digital payments, and direct benefit transfers that reached the poor during lockdown.

Supply and logistics

• Lifeline UDAN flights and drones moved medical supplies, and online portals tracked hospital beds and essential goods.

Limits

• The digital divide excluded many from online classes and vaccine slots; tracing apps raised privacy concerns; misinformation spread as fast as facts; and imported inputs created dependence.

Technology helped detect, treat and cushion the crisis, but it worked only where public-health capacity, privacy safeguards and equal access backed it.

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In 1924 Satyendra Nath Bose derived Planck's law of black-body radiation by counting light quanta in a new way; Einstein extended the method to atoms, and the result became Bose-Einstein statistics.

Bose's work

• The new counting: Bose treated photons as identical and indistinguishable, with any number allowed in one energy state; counting the arrangements this way gave Planck's law without borrowing from classical physics.
• Einstein's part: he translated the paper into German, had it published in the Zeitschrift für Physik in 1924, and applied the statistics to a gas of atoms, predicting that at very low temperature they would settle into a single quantum state.

How it revolutionised physics

• Two families of particles: bosons (named by Paul Dirac) obey Bose's rule, carry integer spin and can crowd into one state; fermions, with half-integer spin, follow Fermi-Dirac statistics and Pauli's exclusion principle.
• Bose-Einstein condensation: Einstein's prediction was realised in the laboratory in 1995 and opened cold-atom physics.
• Explaining the unexplained: lasers (photons are bosons), superfluid helium-4 and superconductivity (electron pairs act as bosons) rest on bosonic behaviour; the W, Z and Higgs particles are bosons too.
• Recognition: Padma Vibhushan (1954) and National Professor (1958); no Nobel Prize, but 'boson' carries his name.

Bose's counting rule gave physics its second kind of quantum statistics; from lasers to condensates, it remains one of the deepest Indian contributions to modern science.

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Nuclear power supplies round-the-clock electricity without carbon emissions, yet accidents, waste and cost keep it contentious; India's three-stage programme ties expansion to long-term energy security built on its thorium.

The facts

• Firm, low-carbon supply: a growing economy needs reliable power beyond import-dependent, polluting coal and intermittent renewables; nuclear plants run continuously on a small land footprint and support climate goals.
• Indigenous capability: mature pressurised heavy water reactor designs, and fleet-mode construction of 700 MW reactors approved in 2017 to cut cost and time.
• Fuel security: the three-stage programme moves from natural-uranium heavy water reactors to fast breeders using plutonium, and then to thorium-based reactors, making the most of scarce uranium and abundant thorium (since then, the 500 MWe Prototype Fast Breeder Reactor at Kalpakkam reached first criticality in April 2026).
• Small share today: nuclear supplies only a sliver of India's electricity, so expansion adds diversity rather than dependence.

The fears

• Safety: Chernobyl and Fukushima show the scale of a worst case; radiation risk, natural hazards and terrorism worry citizens.
• Waste and decommissioning: long-lived radioactive waste needs secure storage for generations, and closing plants is costly.
• Economics: high capital cost and long gestation, when solar tariffs keep falling.
• Liability and regulation: the Civil Liability for Nuclear Damage Act, 2010 shapes how far suppliers will participate, and critics want a regulator more independent of the Department of Atomic Energy.
• Local opposition: land acquisition, lost livelihoods and mistrust at Kudankulam and Jaitapur show that consent cannot be assumed.

Should India expand?

• Yes, in a calibrated way: nuclear complements renewables and storage in a diverse mix and is India's surest route to firm clean power.
• Conditions: an independent regulator, a strong safety culture, indigenous technology and thorium research, sound waste management, open safety information and genuine community consent.

India should keep expanding nuclear power as one pillar of a diverse energy mix, but only at the pace that independent regulation, safety and public trust allow.

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Stem cells are unspecialised cells that renew themselves and can develop into specialised cells such as blood, skin or corneal cells, which makes them the body's repair kit.

What stem cell therapy is

• Stem cells taken from bone marrow, umbilical cord blood or tissue, or made by reprogramming adult cells into induced pluripotent stem cells (Shinya Yamanaka, Nobel Prize 2012), are given to replace or repair damaged cells and tissues.
• Established uses: blood stem cell transplant for leukaemia and thalassaemia; limbal stem cells to rebuild a damaged cornea; cultured skin cells for severe burns.

Advantages over other treatments

• Cure, not control: it replaces defective or lost tissue, so it can cure conditions that drugs and transfusions only manage.
• Lower rejection: the patient's own cells avoid immune rejection and lifelong immunosuppressants.
• Less dependence on scarce donor organs and on repeated transfusions, which carry infection and iron-overload risks.
• New options for diseases with few treatments, such as some blood, eye and spinal disorders, with fewer long-term side effects than drugs.

Cautions

• Beyond blood stem cell transplants and a few proven uses, most therapies remain experimental; unproven clinics, high cost and tumour risk need regulation, so the ICMR-DBT National Guidelines for Stem Cell Research (2013, revised 2017) allow clinical use only within approved trials.

Stem cell therapy promises repair rather than symptom control, but it should reach patients through proven, regulated trials rather than commercial shortcuts.

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