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GS Paper: GS3-15.Science and Technology- Developments and their Applications and Effects in Everyday Life.

  • Vitamin B12 Deficiency & Skin Manifestations 

    Why in the news?

    According to a study published in Canad­ian Family Physician, Vitamin B12 deficiency often shows early dermatological symptoms—such as pigmentation, dryness, and inflammation—before neurological or hematological complications appear.

    What is Vitamin B12?

    • Water-soluble vitamins are essential for: Red blood cell formation, Nerve function, DNA synthesis and Cell growth and repair

    Why Skin Shows Early Signs?

    • B12 deficiency → reduced RBC production → low oxygen delivery to skin → visible skin changes.
    • Weak immunity and impaired nerve function further worsen dermatological issues.
    High-Risk Groups

    More prone to Vitamin B12 deficiency:

    • Vegetarians/vegans
    • Adults > 50 years
    • Individuals with:
      • Gastritis, Crohn’s disease, celiac disease
    • Those taking:
      • Antacids (PPIs/H2 blockers)
      • Metformin
    • People with poor nutrient absorption
    Consider the following pairs: Vitamin : Deficiency disease (2014)

    1. Vitamin C : Scurvy 

    2. Vitamin D : Rickets 

    3. Vitamin E : Night Blindness 

    Which of the pairs given above is/are correctly matched? 

    (a) 1 and 2 only (b) 3 only (c) 1, 2 and 3 only (d) None

  • Big Tech’s contempt for Indian Public Health

    Introduction

    India’s Drugs and Magic Remedies (Objectionable Advertisements) Act, 1954 (DMRA) prohibits advertisements claiming to cure 54 specific medical conditions without proven efficacy. However, the advent of Big Tech advertising has bypassed this framework. Platforms such as Meta, Google, and others are now running sponsored ads for unapproved ayurvedic and homeopathic treatments, violating DMRA provisions. Despite clear illegality, these violations persist due to jurisdictional leniency, U.S.-based corporate protection, and absence of enforcement by Indian regulators.

    Why in the News

    Big Tech’s persistent advertising of unverified health products and ayurvedic “cures” on Indian social media platforms has triggered major concern. The issue marks a systemic regulatory failure, even after India’s decades-old legal framework (DMRA, PNDT Act) prohibits such practices, platforms continue to profit from misleading medical claims. The scale of harm, coupled with cross-border corporate impunity, has made this a critical governance challenge and a new frontier in public health ethics and digital accountability.

    How Has Advertising in Public Health Evolved in the Digital Era?

    1. Shift from Traditional to Digital: Advertisement control has weakened as digital and social media replaced print and broadcast.
    2. Rise of Big Tech Platforms: Meta, Google, and others allow sponsored advertisements promoting “miracle cures,” violating the DMRA.
    3. Absence of Oversight: Digital platforms operate transnationally, making regulatory enforcement difficult.
    4. Public Health Implication: Continuous exposure to false medical claims undermines rational drug use and increases health risks.

    Why Are Big Tech Platforms Violating Indian Law?

    1. Profit-Driven Algorithms: Platforms profit from “sponsored” or “boosted” posts, regardless of legality or health implications.
    2. Weak Accountability: Advertisers and intermediaries claim immunity as “third-party hosts,” avoiding liability under Indian law.
    3. Jurisdictional Escape: Since most Big Tech firms are headquartered in the U.S., Indian laws like DMRA lack cross-border enforcement power.
    4. Regulatory Vacuum: Absence of a unified digital advertising regulator allows platforms to function without deterrence.

    What Legal Frameworks Are Being Ignored?

    1. Drugs and Magic. Remedies (Objectionable Advertisement) Act, 1954: Prohibits advertisements for 54 medical conditions; violation is a criminal offence.
    2. Pre-Conception and Pre-Natal Diagnostic Techniques (PNDT) (Prohibition of Sex Selection) Act, 1994: Bans sex-selection advertisements; Big Tech platforms earlier violated this as well.
    3. Drugs & Cosmetics Act, 1940: Requires all medicines to be clinically established before advertising.
    4. IT Act, 2000 (Section 79): Provides conditional immunity to intermediaries, which is being misused to escape responsibility.
    5. U.S. Corporate Protection: American law shields these corporations from Indian prosecution, leading to managerial impunity.

    What Are the Broader Implications for Governance and Sovereignty?

    1. Erosion of Regulatory Authority: India’s ability to enforce its health and advertising laws is weakened.
    2. Public Interest vs. Corporate Freedom: Public health suffers as profit-driven digital advertising goes unchecked.
    3. Failure of Accountability Mechanisms: Courts and regulators have struggled to bring Big Tech executives under Indian jurisdiction.
    4. Threat to Rule of Law: Unequal treatment between Indian entities and global corporations undermines trust in domestic regulation.

    What Policy Reforms Are Needed?

    1. Legal Recalibration: DMRA and PNDT Act need alignment with the Information Technology Act to hold intermediaries accountable.
    2. Managerial Responsibility: Indian courts should compel Big Tech executives to appear before regulators and face prosecution if violations persist.
    3. Strengthened Digital Health Advertising Rules: Mandate health ads to carry verification tags or disclaimers by government-authorized bodies.
    4. Bilateral Cooperation: India-U.S. digital diplomacy must address cross-border legal immunity for tech corporations.
    5. Institutional Oversight: Establish a Digital Health Advertising Authority (DHAA) under the Ministry of Health to oversee compliance.

    Conclusion

    Big Tech’s disregard for Indian health advertising laws symbolizes the intersection of technology, law, and public welfare. Without regulatory modernization and corporate accountability, digital platforms will continue to operate beyond the reach of Indian law. Ensuring managerial accountability, legal parity, and public health protection must now be central to India’s digital governance reform agenda.

    PYQ Relevance

    [UPSC 2023] Introduce the concept of Artificial Intelligence (AI). How does AI help clinical diagnosis? Do you perceive any threat to privacy of the individual in the use of AI in healthcare?”Introduce the concept of Artificial Intelligence (AI). How does AI help clinical diagnosis? Do you perceive any threat to privacy of the individual in the use of AI in healthcare?

    Linkage: Health related topics are a recurring theme in both GS2 and GS3 papers. The growing use of AI by Big Tech in healthcare mirrors the same challenge of data misuse and weak accountability seen in misleading health advertisements. Both reflect how unchecked digital algorithms can exploit personal health data for profit, posing grave risks to privacy and public trust in India’s health governance system.

  • Akash Missile System 

    Why in the News?

    India has pitched for the supply of the Akash missile system to Brazil.

    akash

    About Akash Missile System:

    • Overview: Developed by the Defence Research and Development Organisation (DRDO) and manufactured by Bharat Dynamics Ltd (BDL).
    • Type: A short-range Surface-to-Air Missile (SAM) designed to defend against aircraft, UAVs, and helicopters.
    • Operational Users: Inducted by both the Indian Army and the Indian Air Force, forming part of India’s layered air defence grid.
    • Purpose: Protects vital assets from aerial threats within the short to medium range segment.
    • Deployment Mode: Mounted on mobile launchers for rapid positioning, flexibility, and operational agility.
    • Comparison: Functionally comparable to Israel’s Iron Dome, though Akash focuses on intercepting larger aerial targets rather than small projectiles.

    Key Features:

    • Range & Altitude: Effective range 4.5–25 km; altitude coverage 100 m–20 km.
    • Engagement Capacity: A single firing unit can engage four targets simultaneously in both autonomous and group modes.
    • Speed & Accuracy: Capable of high-speed interceptions with radar-guided precision.
    • Propulsion & Dimensions: Length 5.87 m, diameter 350 mm, weight 710 kg; powered by solid-fuel propulsion.
    • Automation: Fully automated system ensuring rapid reaction time from detection to neutralization.
    • ECCM Capability: Built-in Electronic Counter-Counter Measures (ECCM) to resist enemy jamming
    [UPSC 2023] Consider the following statements:

    1. Ballistic missiles are jet-propelled at subsonic speeds throughout their fights, while cruise missiles are rocket-powered only in the initial phase of flight.

    2. Agni-V is a medium-range supersonic cruise missile, while BrahMos is a solid-fuelled intercontinental ballistic missile.

    Which of the statements given above is/are correct?

    Options: (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2*

     

  • SARAL tool to simplify Scientific Research Papers

    Why in the News?

    The Anusandhan National Research Foundation (ANRF), India’s newest science funding agency, has launched a digital tool called SARAL (Simplified and Automated Research Amplification and Learning) to make scientific research more accessible.

    What is Anusandhan National Research Foundation (ANRF)?

    • Establishment: Created under the ANRF Act, 2023, replacing the Science and Engineering Research Board (SERB).
    • Nature: Acts as India’s apex science funding and policy-making body.

    • Mission & Objectives: 

      • Raise India’s R&D spending from 0.7% to 2% of GDP by 2030.
      • Mobilise 70% private sector participation in research funding.
      • Promote interdisciplinary research across sciences, technology, health, agriculture, humanities, and social sciences.
      • Align research with Viksit Bharat 2047 and the National Education Policy (NEP).

    • Structure:

      • Chairperson: Prime Minister of India (ex-officio).
      • Vice Presidents: Union Ministers of Science & Technology and Education.
      • Member Secretary: Principal Scientific Advisor.
      • Guided by a Governing Council and Executive Council for policy and funding.

    About SARAL:

    • Developer: Created by IIIT Hyderabad under the guidance of the Anusandhan National Research Foundation (ANRF).
    • Purpose: Designed to make complex research papers accessible to students, professionals, and the general public.
    • AI Use: Generates summaries in multiple formats such as slides, videos, posters, and podcasts.
    • Language Support: Available in 11 Indian languages, ensuring wider inclusivity in science communication.
    • Workflow: Users upload research papers (LaTeX, arXiv links, PDFs); AI divides into sections (Introduction, Methodology, Results, Discussion, Conclusion); it produces editable slides and video summaries.
    • Significance:
      • Democratises science by converting research into layman-friendly outputs.
      • Enhances science communication and outreach.
      • Builds awareness of cutting-edge research across disciplines.
    [UPSC 2015] Which of the following statements is/are correct regarding National Innovation Foundation-India (NIF)?

    1. NIF is an autonomous body of the Department of Science and Technology under the Central Government.

    2. NIF is an initiative to strengthen the highly advanced scientific research in India’s premier scientific institutions in collaboration with highly advanced foreign scientific institutions.

    Select the correct answer using the code given below:

    (a) 1 only* (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2

     

  • [pib] Siphon-Based Thermal Desalination System

    Why in the News?

    Researchers at the Indian Institute of Science (IISc) have developed a siphon-based thermal desalination system that overcomes siltation issues, offering a low-cost and scalable solution.

    About Siphon-Based Thermal Desalination System:

    • Overview: Developed by Indian Institute of Science (IISc) researchers to overcome the inefficiencies of conventional solar stills.
    • Purpose: Designed as a low-cost, scalable, and sustainable freshwater solution for off-grid and water-stressed regions.

    • Working: 

      • Principle: Works on siphonage, where a fabric wick draws salty water and gravity maintains continuous flow.
      • Innovation: A grooved metallic surface flushes away salt deposits before crystallization, preventing clogging.
      • Process: Salty water evaporates as a thin film on a heated surface and condenses just 2 mm away on a cooler surface, ensuring high efficiency.

    Key Features:

    • High Efficiency: Generates >6 liters of freshwater per sq. m per hour under sunlight — several times more than conventional solar stills.
    • Multistage Design: Uses stacked evaporator–condenser pairs to recycle heat and boost output.
    • Salt Resistance: Handles up to 20% salinity without clogging, making it effective even for brine treatment.
    • Affordable Materials: Built from aluminum and fabric, keeping costs low.
    • Energy Flexibility: Operates on solar power or waste heat, adaptable to different settings.
    • Scalable Applications: Useful for villages, disaster zones, and island communities.
    • Sustainability: Offers a clean, low-maintenance desalination method without reliance on complex machinery.
    [UPSC 2008] Where was the first desalination plant in India to produce one lakh liters of freshwater per day based on low-temperature thermal desalination principle commissioned?

    Options: (a) Kavaratti * (b) Port Blair (c) Mangalore (d) Valsad

     

  • Delhi to witness Artificial Rain through Cloud Seeding

    Why in the News?

    The Delhi government is planning to trial cloud-seeding to trigger artificial rain to combat air pollution ahead of winters.

    About Cloud Seeding:

    • About: It is a microclimate management technique aimed at altering precipitation patterns by dispersing substances into clouds to stimulate rainfall or snowfall.
    • Why it is used: It is used to mitigate hail, disperse fog, and either induce precipitation or prevent it from occurring in subsequent days.
    • Techniques include:
      • Static Cloud Seeding: Chemicals are introduced into cold clouds already containing supercooled water droplets, encouraging the formation of ice crystals.
      • Hygroscopic Cloud Seeding: Salts are sprayed into the base of warm clouds to act as condensation nuclei, increasing the number and size of water droplets.
      • Dynamic Cloud Seeding: This method involves boosting vertical air currents to enhance moisture passage through the clouds, leading to more rain.
    • Common Cloud Seeding Chemicals:
      • Silver iodide (AgI): Preferred for its ice-like crystalline properties.
      • Potassium iodide (KI): Functions similarly to silver iodide.
      • Dry ice (solid CO₂): Used to rapidly cool cloud droplets, aiding rain formation.
      • Liquid propane: Used in specific cloud types, effective at higher temperatures.
      • Sodium chloride and calcium chloride: Used in hygroscopic (warm) cloud seeding methods.
      • Bismuth tri-iodide (BiI₃): Sometimes used based on experimental or environmental considerations.
    • Dispersion methods range from aircraft and ground-based generators to newer approaches like drones delivering electric charges or infrared laser pulses.

    Limitations: 

    • Concerns persist regarding the potential accumulation of seeding agents in sensitive ecosystems, although detailed studies have shown negligible impacts.
    • The chemicals used, such as silver iodide, may potentially damage the environment and cause health issues like iodine poisoning in high concentrations
    [UPSC 2025] Artificial way of causing rainfall to reduce air pollution makes use of:

    (a) silver iodide and potassium iodide *

    (b) silver nitrate and potassium iodide

    (c) silver iodide and potassium nitrate

    (d) silver nitrate and potassium chloride

     

  • What is Portable Ion Chromatography?

    Why in the News?

    Australian scientists have developed a simpler, portable version of ion chromatography called Aquamonitrix, enabling field-based analysis of nitrate and nitrite ions.

    About Ion Chromatography:

    • Overview: A laboratory technique used to separate and measure ions (charged particles) in a sample.
    • Process: A liquid sample is passed through a long column that separates ions based on their properties.
    • Equipment: Requires large, complex, and costly lab machines.
    • Use in Environment: Detects harmful ions like nitrate and nitrite that pollute soil and water.

    What is Aquamonitrix?

    • Overview: A portable ion chromatograph designed by the University of Tasmania (Australia).
    • Features: Small, battery-operated, and nearly 10 times cheaper than lab equipment.
    • Testing: Students tested it on soil pore water, measuring nitrate and nitrite levels accurately when compared with lab results.
    • How it Works?
      • Soil water collected with a vacuum pump and filtered.
      • Water injected into the Aquamonitrix unit.
      • Uses a sodium chloride solution to carry the sample.
      • Equipped with a UV light detector, showing nitrate and nitrite as clear peaks.
      • Simpler design avoids messy interference from multiple ions.

    Applications:

    • Environment: Monitoring nitrate and nitrite pollution in soil and water.
    • Agriculture: Helps optimise fertiliser use and reduce overuse.
    • Water Safety: Tests drinking water quality on site.
    • Education: Serves as a teaching tool linking classroom to real-world chemistry.
    [UPSC 2024] “Membrane Bioreactors” are often discussed in the context of:

    Options: (a) Assisted reproductive technologies

    (b) Drug delivery nanotechnologies

    (c) Vaccine production technologies

    (d) Wastewater treatment technologies*

     

  • [pib] Adi Vaani App: India’s First Tribal AI Translator

    Why in the News?

    The Ministry of Tribal Affairs has launched the Beta Version of “Adi Vaani”, India’s first AI-based translator for tribal languages.

    About Adi Vaani:

    • What is it: India’s first AI-powered translator for tribal languages.
    • Launch: Released in Beta Version (2025) by the Ministry of Tribal Affairs.
    • Inception: Developed under Janjatiya Gaurav Varsh to empower tribal communities and safeguard endangered tribal languages.
    • Created by: A team led by IIT Delhi with BITS Pilani, IIIT Hyderabad, IIIT Nava Raipur, and Tribal Research Institutes.
    • Impact: Strengthens digital literacy, ensures inclusive governance, preserves cultural identity, and positions India as a global leader in AI for endangered languages.

    Key Features:

    • Translation Modes: Text-to-Text, Text-to-Speech, Speech-to-Text, and Speech-to-Speech.
    • Languages (Beta): Santali, Bhili, Mundari, and Gondi. Kui and Garo to be added next.
    • AI Models: Based on NLLB (No Language Left Behind) and IndicTrans2, adapted for low-resource languages.
    • Community-Driven: Data collected, validated, and iteratively developed by local experts and Tribal Research Institutes.
    • Toolkit Additions: OCR for digitizing manuscripts, bilingual dictionaries, and curated repositories.
    [UPSC 2020] With the present state of development, Artificial Intelligence can effectively do which of the following?

    1. Bring down electricity consumption in industrial units 2. Create meaningful short stories and songs

    3. Disease diagnosis 4. Text-to-Speech Conversion

    5. Wireless transmission of electrical energy

    Options: (a) 1, 2, 3 and 5 only (b) 1, 3 and 4 only* (c) 2, 4 and 5 only (d) 1, 2, 3, 4 and 5

     

  • ClassGPT: How AI is reshaping campuses

    Introduction

    Artificial Intelligence (AI), particularly generative models like ChatGPT and Gemini, has become both a boon and a challenge in higher education. Students increasingly rely on AI for assignments, summaries, coding, and even emails, while faculty members grapple with maintaining originality, academic honesty, and critical thinking. With AI growing faster than existing regulatory or pedagogical frameworks, Indian institutions are experimenting with varied approaches, ranging from outright bans to integration into curricula. The choices made today will determine not just the future of learning but also India’s knowledge economy and workforce readiness.

    The Changing Landscape of Education with AI

    How widespread is AI usage among students and teachers

    1. IIT Delhi Survey (2024): Four out of five students admitted to using AI, often several times a week. One in ten subscribed to premium versions.
    2. Faculty usage: 77% of surveyed teachers used AI for summarising papers, creating slides, or drafting communication.
    3. Student motivations: Simplification of concepts, summarisation of material, mind maps, and scenario simulations.
    4. Concerns: Errors in math, flawed debugging, weak context handling.

    The integrity dilemma in classrooms

    1. Blurred lines: Students question whether using AI counts as “cheating” or “time-saving.”
    2. Academic honesty: IIT Delhi’s committee recommended rewriting plagiarism policies to require disclosure of AI use.
    3. Critical thinking loss: Faculty fear students may accept AI answers as “Truth” without questioning them.

    Institutional responses in India

    • Policy innovations:
      1. IIT Delhi – integration of AI/ML in curricula, AI workshops, campus-wide licenses.
      2. IIIT Delhi – shifted evaluation to 90% exams, 10% assignments.
      3. IIM Ranchi – evaluation rubric for responsible AI integration.
      4. Shiv Nadar University – five-level “Gen AI Assessment Scale” from prohibition to responsible autonomy.
      5. Ashoka University – AI literacy courses, foundation modules, ethics of AI curriculum.
      6. Strict resistance: Some universities (Delhi University’s Dept. of Education) enforce “No AI” policies, insisting on handwritten assignments.
    • Pedagogical experiments with AI
      1. Classroom integration: AI tools are increasingly used to automate routine tasks like code generation, freeing classroom time for higher-order problem-solving.
      2. Assessment innovation: Institutions are shifting towards interactive methods such as AI-assisted viva voce, project-based evaluation, and scenario testing to ensure genuine understanding.
      3. Ethics in curriculum: Courses on “Ethics of AI” and AI literacy modules are being introduced to sensitise students towards responsible and transparent usage.
      4. Balanced usage: AI is deployed after core concepts are taught, ensuring students retain critical thinking and do not outsource judgment entirely.

    Global responses and comparative perspectives

    1. USA: Princeton provides ChatGPT licenses; Oxford mandates disclosure but allows professors to decide; assignments redesigned to integrate AI.
    2. Australia: TEQSA guidelines legitimise AI but require mandatory disclosure; oral exams and viva voce are making a comeback.
    3. UK: Universities pilot TeacherMatic to ensure sector-wide learning models.

    Conclusion

    Generative AI has irreversibly entered the Indian classroom. The challenge is not whether to allow or ban it but how to regulate, integrate, and ethically harness it. From IITs’ committees to global universities’ adaptive models, the world is learning that AI can either weaken critical thinking or be a catalyst for higher-order learning. For India, the stakes are especially high: with its demographic dividend and growing tech economy, how students learn today will define the nation’s competitiveness tomorrow.

    Value Addition

    Real-Time Usage of AI in Education

    1. Adaptive Learning Platforms : AI customises lesson plans, adjusting pace and difficulty based on student performance, ensuring personalised learning outcomes.
    2. Automated Assessment and Feedback : AI evaluates tests, essays, coding tasks, and provides instant feedback, saving teacher time and helping students improve faster.
    3. Language Translation and Accessibility : Real-time translation, speech-to-text, and text-to-speech tools remove linguistic barriers, supporting multilingual and differently-abled learners.
    4. AI-Powered Virtual Tutors : Chatbots and digital assistants are available 24×7 to clarify doubts, simulate problem-solving, and provide personalised tutoring.
    5. Plagiarism and Academic Integrity Checks : AI tools detect plagiarism and even AI-generated content, ensuring transparency and originality in student submissions.
    6. Immersive Learning with AI + AR/VR : Virtual labs and simulations powered by AI allow safe, hands-on learning in science, medicine, and engineering.
    7. Administrative Automation : AI automates attendance, timetabling, grading records, and performance monitoring, reducing non-teaching workload for faculty.
    8. Industry 4.0 Skill Development : AI-based coding assistants, real-time debugging, and project simulators prepare students for jobs in data science, robotics, and emerging tech.

    PYQ Relevance

    [UPSC 2023]  Introduce the concept of Artificial Intelligence (AI). How does AI help clinical diagnosis? Do you perceive any threat to privacy of the individual in the use of AI in the healthcare?

    Linkage: AI’s growing role in education parallels its use in healthcare, where it aids efficiency but raises ethical and privacy concerns. Just as AI in clinical diagnosis demands accuracy, transparency, and accountability, AI in classrooms requires disclosure, integrity, and critical oversight. Both contexts highlight the larger governance challenge of balancing innovation with responsibility.

  • How are Soaps and Detergents manufactured?

    Why in the News?

    This newscard is an excerpt from the original article published in ‘The Hindu’.

    About Soap:

    • Composition: Soap is sodium (Na) or potassium (K) salt of fatty acids derived from vegetable oils or animal fats.
    • Formula: Solid soaps are RCOONa, liquid soaps are RCOOK.
    • Function: Cleansing agent due to dual hydrophilic (water-attracting) and hydrophobic (oil-attracting) nature.
    • History: Used since 2800 BC in Mesopotamia and ancient India (soap nuts, bark, flowers). Became mass-produced during the Industrial Revolution, initially a luxury.

    Soap-Making Process

    • Raw Materials: Oils such as coconut, olive, palm, sunflower provide triglycerides.
    • Hydrolysis: Oils hydrolysed with hot water under pressure → fatty acids + glycerin.
    • Saponification: Fatty acids react with sodium hydroxide (NaOH) → soap (RCOONa) + water.
    • Processing: Soap dried into noodles, blended with perfumes, colours, fillers, additives.
    • Shaping: Extruded, cut, and stamped into bars.
    • Quality: Total Fatty Matter (TFM) indicates quality; higher TFM = better cleansing.
    • Production Scale: Modern automated lines make 600–700 soaps per minute.

    Ecological Impact of Soap

    • Biodegradability: Traditional soaps are biodegradable and safer for the environment.
    • Detergents: Synthetic alternatives developed during World War I oil shortages; more efficient but harmful.
    • Pollution: Surfactants and phosphates in detergents cause nutrient pollution and persist in ecosystems.
    [UPSC 2002] Consider the following statements:

    Assertion (A) Synthetic detergents can lather well in hard water.

    Reason (R): Synthetic detergents form soluble calcium and magnesium salts with hard water.

    Which one of the following is correct in respect of the above statements?

    Options:

    (a) Both A and R are individually true and R is the correct explanation of A *

    (b) Both A and R are individually true but R is not a correct explanation of A

    (c) A is true but R is false

    (d) A is false but R is true