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Subject: Science and Technology

  • Guardians of India’s Maritime Frontiers

    Why in News?

    The Indian Navy recently commissioned INS Mahendragiri, INS Dunagiri, INS Sanshodhak, and INS Agray, strengthening India’s indigenous maritime capabilities.

    Key Highlights

    • Three indigenous naval classes strengthen India’s layered maritime security:
      • Nilgiri Class: Stealth Frigates (Project 17A)
      • Sandhayak Class: Survey Vessel (Large)
      • Arnala Class: Anti-Submarine Warfare Shallow Water Craft (ASW-SWC)
    • Designed by the Warship Design Bureau (WDB) with high indigenous content under Aatmanirbhar Bharat.
    • Protect India’s 11,098 km coastline, 2.4 million sq km Exclusive Economic Zone (EEZ), and sea lanes carrying ~90% of India’s trade by volume.

    About the Three Classes

    • Nilgiri Class (Project 17A): Next-generation stealth guided missile frigates for anti-air, anti-surface, and anti-submarine warfare.
      • Equipped with BrahMos missiles, advanced radar, sonar, and helicopters.
    • Sandhayak Class: Conducts hydrographic surveys, seabed mapping, and nautical charting.
      • Supports the Blue Economy, navigation safety, and disaster relief.
    • Arnala Class: Designed for coastal anti-submarine warfare in shallow waters.
      • Equipped with lightweight torpedoes, ASW rockets, and shallow-water sonar.

    Strategic Significance

    • Strengthens Aatmanirbhar Bharat through indigenous shipbuilding.
    • Supports SAGAR (Security and Growth for All in the Region) and MAHASAGAR (Mutual and Holistic Advancement for Security and Growth Across Regions) visions.
    • Enhances maritime security, defence exports, and the Blue Economy.

    [2016] Which one of the following is the best description of ‘INS Astradharini’, that was in the news recently?

    [A] Amphibious warfare ship

    [B] Nuclear-powered submarine

    [C] Torpedo launch and recovery vessel

    [D] Nuclear-powered aircraft carrier

  • Gaganyaan: ISRO Successfully Tests Key Crew Module Systems

    Why in News?

    The Indian Space Research Organisation (ISRO) successfully conducted three major qualification tests of the Gaganyaan Crew Module to enhance astronaut safety during re-entry and recovery.

    Key Highlights

    • Crew Module Uprighting System (CMUS): Uses a stored cold gas inflation system to automatically restore the crew module to an upright position after sea splashdown, ensuring crew safety.
    • Crew Module Umbilical System (CSU-2): Successfully tested the separation of the Crew Module Umbilical-2 (CSU-2), which connects the Crew Module (CM) and Service Module (SM).
      • Enables clean separation before atmospheric re-entry while maintaining structural integrity.
    • Apex Cover Separation Test: Validated the structural integrity during separation of the apex cover, which protects the parachute system.
      • The cover separates before parachute deployment to ensure safe deceleration and landing.
      • Note: Parachute systems are deployed to slow descents through the atmosphere or space.

    About Gaganyaan Mission

    • India’s first indigenous human spaceflight mission.
    • Implemented by: Indian Space Research Organisation (ISRO).
    • Objective: Demonstrate India’s capability to send three astronauts to Low Earth Orbit (LEO) (about 400 km) for up to 3 days and safely return them to Earth.

    Significance

    • Strengthens astronaut safety during splashdown and re-entry.
    • Validates critical crew escape and recovery systems.
    • Advances India’s human spaceflight capability and future space exploration.

    [2025] Consider the following space missions:
    I. Axiom-4
    II. SpaDeX
    III. Gaganyaan
    How many of the space missions given above encourage and support microgravity research?

    [A] Only one

    [B] Only two

    [C] All the three

    [D] None

  • CSIR NIScPR AI Enabled Institutional Repositories using DSpace

    Why in News?

    CSIR National Institute of Science Communication and Policy Research (CSIR NIScPR) conducted a five day skill training programme (6 to 10 July 2026) on AI enabled Institutional Repositories using DSpace under the CSIR Integrated Skill Initiative (Phase III).

    Key Highlights

    • Aimed at training library professionals, researchers, academicians, students, and IT professionals.
    • Focused on developing and managing AI enabled institutional repositories using the open source DSpace platform.
    • Training covered:
      • DSpace architecture and administration
      • Linux and DSpace installation
      • Dublin Core metadata management
      • Repository customization and backup
      • AI based metadata extraction and semantic search
    • Included hands on laboratory sessions and exposure to SARAL AI and the NIScPR Herbarium.
    • 25 participants from universities, research institutions, and libraries completed the programme.

    About CSIR NIScPR

    • Constituent laboratory of the Council of Scientific and Industrial Research (CSIR).
    • Established in 2021 through the merger of:
      • NISCAIR: National Institute of Science Communication and Information Resources.
      • NISTADS: National Institute of Science, Technology and Development Studies.
    • Promotes science communication, policy research, scholarly publishing, and digital knowledge management.

    About DSpace

    • Open source software for creating and managing institutional digital repositories.
    • Preserves and provides open access to research publications, theses, datasets, and other scholarly content.
    • Supports metadata standards such as Dublin Core and enables long term digital preservation.

    [2020] With the print 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
    Select the correct answer using the code given below:

    [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

  • Why Weekly Diabetes Shot Could Reshape Treatment

    Why in the News?

    Novo Nordisk launched Awiqli (insulin icodec), the world’s first once-a-week insulin injection, in India, cutting required insulin shots from 365 to 52 a year at Rs 261 per week. The launch targets India’s exceptionally large and growing diabetic population, but insulin use in India has long lagged clinical need because of reluctance among both patients and doctors to initiate insulin therapy.

    How does icodec technically reduce insulin’s dosing burden without changing its clinical effect?

    1. Albumin-binding depot: A fatty acid chain added to the insulin molecule increases its affinity for albumin, a blood protein. Delivered under the skin, the drug binds reversibly to albumin, forming an inactive depot that releases insulin into the bloodstream through the week.
    2. Reduced receptor affinity: Three amino acid substitutions lower the molecule’s affinity for insulin receptors. This slows the rate at which released insulin is used up, without reducing its potency.
    3. Injection frequency reduction: The two modifications together cut insulin injections from 365 days a year to 52 days, making icodec the world’s first long-acting weekly insulin shot.
    4. Clinical equivalence, not clinical superiority: Physicians state icodec’s blood sugar-lowering effect is similar to other insulins. The advance lies in reduced dosing frequency, expected to improve compliance rather than glucose control itself.
    5. Position in insulin’s evolution: Icodec is a genetically engineered insulin analogue (Insulin analogue: a modified version of human insulin engineered to alter how long it stays active or how it is absorbed), part of a line of modifications that extend how long insulin stays active in the body.

    Why does India’s insulin gap persist despite insulin’s proven superiority over oral therapy?

    1. Patient reluctance despite clinical failure of pills: Type 2 diabetics who have failed to control blood glucose even on the highest doses of oral medicines remain unwilling to switch to insulin shots, despite the risk of organ, nerve, and eye damage from delay.
    2. Physician-side reluctance: Doctors themselves show reluctance to initiate insulin treatment in patients, delaying transition even when maximal oral therapy has failed.
    3. Insulin’s undeserved stigma: Novo Nordisk India’s managing director states insulin is a drug that is never abused and is highly effective, yet patients avoid it, indicating the barrier is perceptual rather than clinical.
    4. Scale of underuse: Only six million people are currently on insulin in India, a number industry estimates should be at least double, given the population that clinically needs it.
    5. Gendered burden compounding avoidance: Women on multiple daily insulin doses report needing to adjust doses during menstruation, a flexibility burden not addressed by frequency reduction alone.

    Which patient groups does icodec target, and why does the clinical logic differ between type 1 and type 2 diabetes?

    1. First target group: treatment-failed type 2 diabetics: Patients with eight to ten years of diabetes whose pills can no longer control blood glucose are the primary intended users, to prevent further organ and nerve damage from delay.
    2. Second target group: background insulin for type 1 diabetics: Type 1 diabetics need a long-acting basal dose (Basal dose: a steady, long-acting insulin dose that manages blood glucose between meals) alongside meal-time bolus doses (Bolus dose: a fast-acting insulin dose taken around mealtimes based on calorie intake); icodec would add a fourth weekly dose without significantly raising treatment burden.
    3. Why type 2 is the better clinical fit: Type 1 diabetics already take three daily doses, and their blood glucose fluctuates more, requiring frequent dose adjustment that weekly dosing cannot accommodate.
    4. Loss of flexibility as a trade-off: A physician-run survey found women needed to adjust insulin doses during menstruation, a flexibility that a fixed weekly dose foreclosed for type 1 patients.
    5. Type 2’s larger untapped pool: Since 25% to 30% of type 2 diabetics eventually require insulin despite most managing initially on pills, this is the segment with the largest late-stage conversion potential.

    Does icodec’s safety and cost profile remove the practical objections to insulin therapy?

    1. Hypoglycemia risk unchanged: The most common side effect, hypoglycemia (Hypoglycemia: a condition where blood glucose levels fall too low), affects about one in ten people on icodec, matching the risk seen with other daily insulin shots.
    2. Why hypoglycemia appears more noticeable on insulin: Blood glucose is controlled for the first time once insulin is started, making hypoglycemic episodes more apparent; pills can cause hypoglycaemia too, but uncontrolled high glucose on pills masks the comparison.
    3. Weekly cost undercuts existing insulin analogues: Icodec costs Rs 261 a week, compared to Rs 345 to Rs 453 a week for existing insulin analogues, working out to about Rs 50 a day.
    4. Pricing structure: The drug is sold in two pre-filled pen sizes, a 700 ml unit priced at Rs 2,611 and a 2,100 ml unit priced at Rs 7,883, with a typical patient needing around 70 units a week depending on requirement.
    5. Combination potential with weight-loss drugs: Icodec becomes more effective when combined with GLP-1 drugs (GLP-1 drugs: a class of medicines that lower blood glucose and are also used for weight loss), since abdominal obesity reduces insulin sensitivity and raises the insulin needed to process the same amount of sugar.

    Does convenience alone close India’s insulin treatment gap?

    1. Scale of the underlying burden: India currently has 101 million people living with diabetes and 136 million with pre-diabetes, one of the largest such populations in the world.
    2. Projected insulin need over time: Industry estimates suggest 5% to 10% of diabetics would need insulin after five years of pill-based management, rising to 20% to 30% after ten years.
    3. Conservative estimate still implies a large gap: Even at a conservative 20% requirement, the number needing insulin would stand at around 20 million, more than three times the current six million on insulin.
    4. Convenience as the stated lever for closing this gap: Industry framing ties the drug’s adoption prospects explicitly to convenience and comparable cost, not to any claimed improvement in glucose control.
    5. Unaddressed question: Whether reduced dosing frequency by itself overcomes the reluctance documented among both patients and doctors, distinct from cost or frequency, is not established by the launch itself.

    Conclusion

    Icodec’s weekly dosing and competitive pricing directly target the practical barriers of frequency and cost that have long deterred insulin use in India. The deeper barrier is behavioural: both patients and physicians delay insulin initiation despite its established superiority over maximal oral therapy, driven by stigma and reluctance rather than price or frequency alone. Reducing shots from 365 to 52 a year does not by itself address this psychological resistance. Whether convenience translates into earlier insulin initiation, and closes the gap between India’s 101 million diabetics and the roughly 20 million projected to eventually need insulin, will depend on physician-driven behavioural change as much as on the drug’s technical advance.

  • NeoSep1 Trial to Combat Antimicrobial Resistant Neonatal Sepsis

    Why in News?

    India has joined the NeoSep1 international trial to evaluate effective antibiotic combinations for treating antimicrobial resistant (AMR) neonatal sepsis.

    Key Highlights

    • NeoSep1 is a multicentric clinical trial led by GARDP and international partners.
    • India’s first participants were enrolled at:
      • JIPMER, Puducherry
      • PGIMS, Rohtak
    • The trial aims to enrol 3,000 newborns across Asia and Africa by 2028.
    • Uses a Personalised Randomised Controlled Trial (PRACTical) design to identify the most effective antibiotic regimens.
    • Primary outcome: 28 day survival; secondary outcomes include 90 day survival, hospital stay, and need for additional antibiotics.

    Neonatal Sepsis

    • A life threatening bloodstream infection in infants below 90 days of age.
    • Classified as:
      • Early onset: Within 72 hours of birth.
      • Late onset: Up to 28 to 90 days after birth.
    • Premature and low birth weight babies are at the highest risk.

    India and AMR

    • Accounts for 30 to 40% of neonatal deaths in India.
    • Causes an estimated 2 to 2.5 lakh preventable deaths annually.
    • Predominant pathogens: Klebsiella pneumoniae. Escherichia coli. Acinetobacter spp. Pseudomonas aeruginosa
    • These organisms often exhibit multidrug resistance, unlike developed countries where Group B Streptococcus is the leading cause.

    [2019] Which of the following are the reasons for the occurrence of multi-drug resistance in microbial pathogens in India?
    1. Genetic predisposition of some people
    2. Taking incorrect doses of antibiotics to cure diseases
    3. Using antibiotics in livestock farming
    4. Multiple chronic diseases in some people
    Select the correct answer using the code given below.

    [A] 1 and 2

    [B] 2 and 3 only

    [C] 1, 3 and 4

    [D] 2, 3 and 4

  • China Achieves First Controlled Recovery of Reusable Rocket Booster

    Why in News?

    China has successfully conducted its first controlled recovery of an orbital class reusable rocket booster during the maiden launch of the Long March 10B carrier rocket, marking a significant milestone in its reusable space technology.

    Key Highlights

    • Long March 10B successfully placed its payload into the designated orbit.
    • After stage separation, the first stage booster returned safely and was captured on a sea based platform using a net capture system.
    • This marks China’s first successful controlled recovery of an orbital class rocket booster.
    • The achievement follows SpaceX, which became the first to recover an orbital class rocket booster in December 2015.
    • Two previous Chinese attempts at vertical landing in December 2025 had failed.

    What is a Reusable Launch Vehicle (RLV)?

    • A launch vehicle designed to recover and reuse some or all of its components after launch.
    • Typically, the first stage booster is recovered since it accounts for a major share of launch costs.
    • Recovery methods include:
      • Vertical landing on land or drone ships (SpaceX).
      • Sea based platform recovery using net capture (Long March 10B).
    • Reusability significantly lowers the cost of access to space.

    Benefits of Reusable Rocket Technology

    • Reduces launch costs through multiple reuse of boosters.
    • Enables higher launch frequency.
    • Improves commercial viability of space missions.
    • Supports deep space exploration and satellite deployment.
    • Reduces manufacturing time and resource consumption.

    China’s Long March Rocket Family

    • Developed by the China Academy of Launch Vehicle Technology (CALT).
    • Serves as China’s primary family of orbital launch vehicles.
    • Used for: Satellite launches. Human spaceflight missions. Lunar and deep space exploration.
    • Long March 10 is being developed for China’s future crewed Moon missions.

    India’s Reusable Launch Vehicle (RLV) Programme

    • Developed by ISRO.
    • Aims to create a fully reusable space transportation system.
    • Key milestones:
      • RLV-TD (Reusable Launch Vehicle Technology Demonstrator) first flew in 2016.
      • LEX (Landing Experiment) successfully demonstrated autonomous runway landing in 2023.
      • LEX-02 and LEX-03 further validated autonomous landing technologies.
    • Intended to reduce launch costs and improve access to space.

    [2018] With reference to India’s satellite launch vehicles, consider the following statements :
    1.PSLVs launch satellites useful for Earth resources monitoring whereas GSLVs are designed mainly to launch communication satellites.
    2.Satellites launched by PSLV appear to remain permanently fixed in the same position in the sky, as viewed from a particular location on Earth.
    3.GSLV Mk III is a four-stage launch vehicle with the first and third stages using solid rocket motors, and the second and fourth stages using liquid rocket engines.
    Which of the statements given above is/are correct?

    [A] 1 only

    [B] 2 and 3

    [C] 1 and 2

    [D] 3 only

  • DRDO Successfully Tests Pinaka Long Range Guided Rocket

    Why in News?

    The Defence Research and Development Organisation (DRDO) successfully conducted a flight test of the Pinaka Long Range Guided Rocket (LRGR) from the Integrated Test Range (ITR), Chandipur, Odisha. The test validated its user defined minimum strike range of 60 km and demonstrated high precision strike capability.

    Key Highlights

    • Successfully validated the minimum strike range of 60 km.
    • The rocket executed all planned in flight manoeuvres and accurately hit the designated target.
    • It followed the predicted trajectory with high precision.
    • Launched from an in service Pinaka launcher, demonstrating compatibility with multiple Pinaka rocket variants.
    • This enhances operational flexibility for the Indian Army.

    Development

    • Designed by the Armament Research and Development Establishment (ARDE), Pune.
    • Developed in collaboration with the High Energy Materials Research Laboratory (HEMRL), Pune.
    • Supported by the Defence Research and Development Laboratory (DRDL), Hyderabad and Research Centre Imarat (RCI), Hyderabad.
    • Flight trial coordinated by the Integrated Test Range (ITR) and Proof and Experimental Establishment (PXE), Chandipur.

    About Pinaka Rocket System

    • Pinaka is an indigenously developed Multi Barrel Rocket Launcher (MBRL).
    • Developed by DRDO for the Indian Army.
    • Named after Lord Shiva’s bow, Pinaka.
    • Provides rapid, high volume artillery fire against enemy positions.
    • Mounted on a high mobility vehicle.
    • Can fire 12 rockets in about 44 seconds.
    • Suitable for: Area suppression, Counter battery fire, Destruction of troop concentrations, and Neutralising enemy logistics and command centres

    Pinaka Variants

    • Pinaka Mk I: Range of about 37 to 40 km.
    • Guided Pinaka: Precision guided rocket with a range of about 75 km.
    • Pinaka Enhanced Range (ER): Range of about 90 km.
    • Pinaka Long Range Guided Rocket (LRGR): Maximum range of about 120 km, while the latest test validated a user defined strike range of 60 km.

    [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 fight.
    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?

    [A] 1 only

    [B] 2 only

    [C] Both 1 and 2

    [D] Neither 1 nor 2

  • Mission Drishti Loses Communication After Solar Storm

    Why in News?

    Mission Drishti, developed by Bengaluru based GalaxEye, lost communication after a geomagnetic solar storm affected the satellite during the Launch and Early Orbit Phase (LEOP).

    Key Highlights

    • Launched on 3 May 2026 aboard SpaceX Falcon 9 from Vandenberg, California.
    • World’s first OptoSAR satellite, combining optical imaging and Synthetic Aperture Radar (SAR).
    • India’s largest privately developed Earth observation satellite.
    • Radiation from the solar storm likely affected a critical onboard system, causing communication loss.
    • Recovery efforts are ongoing, but chances of recovery are currently low.

    What is OptoSAR?

    • Integrates optical cameras with Synthetic Aperture Radar (SAR).
    • Provides high-resolution imaging in all weather conditions, including through clouds and at night.
    • Useful for disaster management, agriculture, defence, mapping, and environmental monitoring.

    Significance

    • Validated several indigenous satellite technologies and mission operations.
    • Strengthens India’s private space ecosystem.
    • Lessons from the mission will improve future spacecraft reliability.
    • GalaxEye plans to launch two next-generation OptoSAR satellites within the next 24 months.

    [2022] If a major solar storm (solar flare) reaches the Earth, which of the following are the possible effects on the Earth?:
    1. GPS and navigation systems could fail.
    2. Tsunamis could occur at equatorial regions.
    3. Power grids could be damaged.
    4. Intense auroras could occur over much of the Earth.
    5. Forest fires could take place over much of the planet.
    6. Orbits of the satellites could be disturbed
    7. Shortwave radio communication of the aircraft flying over polar regions could be interrupted.
    Select the correct answer using the code given below;

    [A] 1, 2, 4 and 5 only

    [B] 2, 3, 5, 6 and 7 only

    [C] 1, 3, 4, 6 and 7 only

    [D] 1, 2, 3, 4, 5, 6 and

  • IoT Based Smart Health Tracker for Himalayan Yaks

    Why in News?

    Scientists have developed an Internet of Things (IoT) based smart system to monitor the health, movement, and stress of high altitude yaks in the Himalayan region.

    Key Highlights

    • Developed by scientists from ICAR National Research Centre on Yak (NRC-Y), Dirang (Arunachal Pradesh) and Assam Don Bosco University.
    • The device is attached to a collar worn by the yak.
    • Features:
      • Geo-fencing to track movement.
      • Real time health monitoring.
      • Early prediction of stress and illness.
    • Helps monitor livestock in remote border areas where physical surveillance is difficult.

    Significance

    • Improves yak health and productivity.
    • Supports the livelihoods of Himalayan pastoral communities (Brokpas).
    • Reduces livestock loss and enables timely veterinary intervention.
    • Demonstrates the use of IoT in precision livestock farming.

    Prelims Facts

    • Scientific name: Bos grunniens
    • Known as the “Ship of the Himalayas.”
    • Found above 8,000 feet.
    • India has about 58,000 yaks (20th Livestock Census), with nearly half in Ladakh; others are found in Arunachal Pradesh, Sikkim, Himachal Pradesh, and Uttarakhand.

    [2018] When the alarm of your smartphone rings in the morning, you wake up and tap it to stop the alarm which causes your geyser to be switched on automatically. The smart mirror in your bathroom shows the day’s weather and also indicates the level of water in your overhead tank. After you take some groceries from your refrigerator for making breakfast, it recognises the shortage of stock in it and places an order for the supply of fresh grocery items. When you step’ out of your house and lock the door, all lights, fans, geysers and AC machines get switched off automatically. On your way to office, your car warns you about traffic congestion ahead and suggests an alternative route, and if you are late for a meeting, it sends a message to your office accordingly. In the context of emerging communication technologies, which one of the following terms best applies to the above scenario?

    [A] Border Gateway Protocol

    [B] Internet of Things

    [C] Internet Protocol

    [D] Virtual Private Network

  • INS Mahendragiri (Project 17A Stealth Frigate)

    Why in News?

    The Indian Navy will commission INS Mahendragiri (F38), the sixth Project 17A indigenous stealth frigate, at Visakhapatnam on 11 July 2026.

    Note: Project 17A is a ₹45,000-crore Indian Navy initiative to build seven advanced Nilgiri-class stealth frigates.

    Key Highlights

    • Named after the Mahendragiri Hills in the Eastern Ghats.
    • Designed by the Indian Navy’s Warship Design Bureau (WDB).
    • Built by Mazagon Dock Shipbuilders Limited (MDL), Mumbai.
    • Features over 75% indigenous content, supporting Aatmanirbhar Bharat.
    • Powered by Combined Diesel or Gas (CODOG) propulsion for high speed and long endurance.

    Features

    • Advanced stealth design with reduced radar signature.
    • Equipped with:
      • Surface-to-Surface Missiles (SSM)
      • Surface-to-Air Missiles (SAM)
      • Electronic Warfare (EW) systems
      • Anti-Submarine Warfare (ASW) systems
      • Integrated Combat Management System (CMS)
    • High degree of automation and enhanced survivability.

    Operational Roles

    • Anti-air warfare, Anti-surface warfare, Anti-submarine warfare, Maritime security, Humanitarian Assistance and Disaster Relief (HADR), Search and Rescue (SAR), and Indo-Pacific presence missions

    Significance

    • Strengthens India’s indigenous warship-building capability.
    • Enhances the Indian Navy’s blue-water combat capability.
    • Boosts the domestic defence ecosystem, including MSMEs.
    • Reinforces India’s role as the Preferred Security Partner in the Indian Ocean Region.

    [2026] Which of the following statements with regard to stealth technology is/are correct ?
    1. Stealth objects have a very small radar cross-section and are coated with Radar Absorbing Material.
    2. Stealth objects can be detected using specific frequencies.
    3. Stealth objects are coated with metamaterials to increase the scattering of electromagnetic radiation.
    Select the answer using the code given below :

    [A] 1 only

    [B] 2 and 3 only

    [C] 1 and 2 only

    [D] 1, 2 and 3