The Cascadia Subduction Zone (CSZ) “megathrust” fault is a 1,000 km long dipping fault that stretches from Northern Vancouver Island to Cape Mendocino California. It separates the Juan de Fuca and North America plates.
It is an active convergent boundary where the Pacific Ocean floor is subducting under North America. – and when the fault periodically locks and releases, it can unleash devastating megathrust earthquakes and record-breaking waves.
(Left) A schematic cross section of the Cascadia Subduction Zone shows the ocean floor plate (light grey) moving under the North American continental plate.
The fault zone is not a continuous structure but is divided into at least four segments and is divided by buried features, including big faults.
Causes of the segmentation: Differing composition of rocks at the rigid edge of the overriding North American continental plate as they are formed at different times, with some being denser than others.
This causes the incoming, more pliable oceanic plate to bend and twist to accommodate differences in overlying pressure.
Megathrust fault is a place where tectonic plates move against each other in a highly destructive manner. Such a fault off Japan caused the 2011 Fukushima nuclear disaster.
Megathrust earthquakes are the most powerful on Earth, and they arise from subduction zones.
Context (IE): In the first Cabinet meeting of the third term, the PM approved assistance for constructing three crore houses under the Pradhan Mantri Awas Yojana (PMAY).
Of the 3 crore houses, two crore will be built under PMAY-Gramin and one crore under PMAY-Urban.
Pradhan Mantri Awas Yojana (PMAY)
The Pradhan Mantri Awas Yojana (PMAY) is a flagship housing scheme (centrally sponsored) launched by the Government of India in 2015 to provide affordable housing to the urban and rural poor.
Pradhan Mantri Awas Yojana (PMAY) – Rural or Gramin
To provide pucca (permanent) houses with basic amenities to all houseless households and those living in kutcha (temporary) and dilapidated houses in rural areas.
Target Beneficiaries: Households with an annual income of up to Rs. 3 lakh (based on SECC 2011).
Unit Assistance: Financial assistance of Rs. 1.20 lakh in plain areas and Rs. 1.30 lakh in hilly/difficult areas is provided for the construction of a house.
The scheme is implemented by the Ministry of Rural Development and is funded by the central and state governments in a 60:40 ratio for most states (90:10 for special category states; 100% for UTs).
Pradhan Mantri Awas Yojana (PMAY) – Urban
To provide affordable housing to the urban poor, including slum dwellers.
Target Beneficiaries: Households with an annual income of up to Rs. 3 lakh (Economically Weaker Sections, or EWS) and Rs. 3-6 lakh (Low-Income Groups, or LIG).
Unit Assistance: Central assistance of Rs. 1.5 lakh for EWS and Rs. 1 lakh for LIG is provided, along with additional benefits like interest subsidies on home loans.
The scheme is implemented by the Ministry of Housing and Urban Affairs and is funded by the central and state governments in a 60:40 ratio for most states.
Components of the scheme:
In-situ Slum Redevelopment (ISSR);
Credit Linked Subsidy Scheme (CLSS) – interest subsidies on home loans.
Affordable Housing in Partnership (AHP) – encourages public-private partnerships and
Beneficiary-led individual house construction/enhancements (BLC),
{GS2 – Polity – IC – Parliament} Council of Ministers (CoM)
Context (IE): The President administered oaths to the new Central Council of Ministers.
Central Council of Ministers
Article 74 states that the Council of Ministers, headed by the Prime Minister (“first among equals”), shall aid and advise the President, who shall act in accordance with their advice.
TheCoM is the real executive authority in India’s parliamentary system of government.
The President appoints the Prime Minister and other ministers on the PM’s advice (Article 75).
The size of the CoM cannot exceed 15% of the total strength of the Lok Sabha. It is added through the 91st Constitutional Amendment Act of 2003.
Article 88 allows ministers to participate in proceedings of both houses of Parliament and joint sessions but does not guarantee them voting rights.
The Prime Minister decides the portfolio of each minister and heads the Cabinet Secretariat, which oversees the day-to-day administration of the government and coordination between ministries.
The CoM is divided into three categories:
Cabinet Ministers
Ministers of State (Independent Charge)
Ministers of State (without Independent charge)
The President is the Head of the State, and the Prime Minister is the Head of the Union Government.
Article 163: There shall be State CoMs headed by the Chief Minister to aid and advise the Governor.
A minister who is not a member of Parliament for six consecutive months will lose their position.
The Deputy PM/CM (if available) is also part of the Council of Ministers.
Cabinet Ministers
Cabinet Ministers are the senior-most members of the CoMs, second only to the Prime Minister.
They head important and strategic ministries like Home Affairs, Finance, Defence, etc. They have the authority to organise meetings and make major policy decisions related to their ministries.
Ministers of State (Independent Charge) [MoS (IC)]
MoS (Independent Charge) are junior to Cabinet Ministers but have independent charge of a ministry.
They are empowered to administer their respective ministry without oversight from Cabinet Ministers or other members of the Council of Ministers. They are not part of the Cabinet.
Ministers of State
Ministers of State assist Cabinet Ministers in the administration and do not have an independent charge.
They are responsible for specific functions delegated to them by their respective Cabinet Ministers.
They are usually given the charge of departments under a ministry.
Crucial ministries like Home, External Affairs, Health, and Education may have two or three Ministers of State working under the Cabinet Minister. They are also not part of the Cabinet.
Deputy Ministers assist cabinet ministers or MoS with administrative, political, and parliamentary duties.
{GS2 – Social Sector – Education} Tamil Nadu’s Campaign Against NEET
The National Testing Agency (NTA) and the Education Ministry have set up a committee to review the results of those who got grace marks.
Why have the results been contested?
An unusually high number of toppers (67) scoring the maximum possible marks.
Awarding “grace marks” to some candidates for claimed time loss.
Grace marks to candidates who answered a question incorrectly based on an inaccuracy in a textbook.
Justice A.K. Rajan Committee
TN government established Justice A.K. Rajan committee to study the impact of NEET on admissions.
Findings
NEET disadvantages students from rural areas, Tamil medium schools, and lower-income families.
Significant rise in seats secured by English medium and wealthier students after NEET’s introduction.
NEET benefits students from CBSE boards at the expense of Tamil Nadu state board students.
NEET scores are not as reliable indicators of merit as state board exam scores.
Average pre-NEET HSC scores for admitted students were higher than post-NEET average NEET scores.
Nearly all students admitted in 2019-20 had received coaching before NEET, creating a financial barrier for underprivileged students.
Recommendations
Eliminating NEET from the admission process.
Using HSC scores, normalised across boards, as the admission criteria.
Re-profile scores to account for socioeconomic and demographic challenges.
National Testing Agency
It is an autonomous and self-reliant testing organisation established by the Ministry of Education.
To conduct entrance examinations for admission/fellowship in higher educational institutions.
The major exams conducted are Joint Entrance Examination (JEE) Main, National Eligibility cum Entrance Test (NEET), Common Management Admission Test (CMAT), Graduate Pharmacy Aptitude Test (GPAT).
{GS3 – Envi – CC} Heatwave as notified disaster
Context (IE): The ongoing spell of extreme heat across the country has once again reopened discussions on the inclusion of heatwaves as one of the notified disasters under the Disaster Management Act.
Heatwaves, though not a new phenomenon in India, are not viewed as a disaster under theDisaster Management Act 2005. It was because heatwaves are a common occurrence during summer and not really an unusual weather event.
What are notified disasters?
Disaster Management Act defines disaster as a “catastrophe, mishap, calamity or grave occurrence” arising from “natural or man-made causes” that results in substantial loss of life, destruction of property, or damage to the environment.
It must also be of such nature which is “beyond the coping capacity” of the community. If such an event happens, then the provisions of the DM Act can be invoked.
The provisions allow states to draw money from funds that have been set up under the law — the National Disaster Response Fund (NDRF) at the national level and the State Disaster Response Fund (SDRF) at the state level.
The states first utilise the funds available in the SDRF, and only if the magnitude of the disaster is unmanageable with the SDRF does the state seek money from the NDRF.
Why heatwaves were not included as notified disasters?
Finance Commission Reluctance
States have put the demand of including heatwaves as a notified disaster before the last three Finance Commissions. However, the Finance Commissions have not entirely been convinced.
As per the 15th Finance Commission, the existing list of notified disasters “covers the needs of the states to a large extent” and did not find merit in the request to include heatwaves.
It, however, endorsed an enabling provision created by the preceding Commission that allowed states to utilisea part of the SDRF money, i.e., up to 10%, for “local disasters” such as lightning or heatwaves, which states could notify on their own.
Using this new enabling provision, at least four states, Haryana, Uttar Pradesh, Odisha, and Kerala, have added heatwaves as local disasters.
Practical Difficulties
The government has to provide monetary compensation, i.e., Rs 4 lakh, for every life lost because of a disaster that is in the notified list. Grievous injuries also have to be compensated. This would place an extra burden on the state exchequer.
Problem in attributing deaths to heatwaves. In most cases, heat itself does not claim lives but aggravates the pre-existing conditions, leading to difficulty in ascertaining if heat was the real cause behind death.
Context (IE | TH): Apple introduced Apple Intelligence, the company’s personal intelligence system that brings generative AI to Apple devices for iPhone, iPad, and Mac.
It combines generative AI capabilities with personal context to deliver personalised intelligence.
It means that it understands user behaviour and comes up with appropriate responses.
It is like ChatGPT but with more contextual awareness — it knows the user’s likes and dislikes and online preferences, will keep a tab on their calendar, etc.
It is backed by Private Cloud Compute, which is claimed to be a new standard for privacy in AI.
Private Cloud Compute (PCC)
PCC is a cloud intelligence system designed specifically for private AI processing.
PCC makes it easy for Apple Intelligence to scale computational capacity between on-device processing and larger, server-based models that run on dedicated Apple Silicon servers.
With PCC, Apple Intelligence can be aware of a user’s personal information without collecting it.
{GS3 – S&T – Space} SpaceX’s Starship
Context (IE):SpaceX’s Starship rocket accomplished its first fully successful test flight. This was SpaceX’s fourth attempt to launch the Starship.
The Starship’s booster (called Super Heavy) was detached from the upper section (or the Starship spacecraft) to make a soft landing in the Gulf of Mexico.
Starship
Starship is a two-stageheavy lift-off vehicle designed to carry crew and/or cargo to Earth orbit, the Moon, Mars, and beyond. It is nearly 120 metres tall, making it the largest rocket ever flown.
The Super Heavy booster consists of 33 Raptor engines that can produce 74 meganewtons of thrust.
NASA’s biggest currently-operational rocket, the Space Launch System (SLS), generates 39 meganewtons off the pad.
These Raptor engines use a 3.6:1 ratio of liquid oxygen (the oxidiser, a chemical that reacts with the fuel to cause combustion) and liquid methane (the fuel).
According to SpaceX, the Super Heavy will be fully reusable and capable of re-entering Earth’s atmosphere after a mission to land at the launch site.
The Starship spacecraft, comprising six Raptor engines and four landing fins, is also fully reusable.
Reducing the cost of space travel
More payload carrying capacity per trip will lower the costs. Further, with the refuelling capacity of Starship’s upper stage, spacecraft can instead be designed for increased payload capacity, thereby fundamentally increasing their value-generating potential.
The Starship rocket system is designed to be entirely and rapidly reusable.
Even NASA’s reusable Space Shuttle spacecraft used a disposable external fuel tank and reusable thrusters, which had to be recovered from the sea, examined, and refurbished, causing delays.
However, SpaceX needs to prove that Starship is safe and reliable while keeping costs low, as it promised. Moreover, progress has been slower than expected.
Context (TH): A study recently published in the journal Nature introduced a kind of portable optical atomic clock that can be used onboard ships.
Inaccurate mechanical clocks
The previous generation of clocks consisting of a quartz crystal oscillator, was performing efficiently.
But the best of such oscillators would be late by a nanosecondafter an hour of efficient performance.
So, if this clock were used to gauge the position of a spacecraft, it would be very prone to error.
To improve on this, atomic clocks were invented.
Atomic clocks
Atomic clocks contain an element like caesium (Cs-133) or calcium and microwave radiation source.
When excited by a microwave, the electrons of caesium or calcium can absorb some of the incident radiation and get excited to a higher state.
For this, microwave radiation has to match the characteristic frequency of the caesium or calcium atom.
Tuning the microwave source and observing at what frequency the transition takes place calculates the exact value of the characteristic frequency, which can be used to measure time accurately.
Atomic clocks are the backbone of the Global Positioning System (GPS). The International Committee for Weights and Measures first used it in 1967 to define the duration of one second.
Frequency refers to the number of waves that cross a particular point in time in one unit of time.
The official definition of a second is the frequency needed for electrons to transition between two levels in a caesium atom.
The accuracy of atomic clocks comes from a feedback mechanism that detects any changes in the resonance frequency and adjusts the microwave radiation to maintain resonance.
Thus, a caesium atomic clock loses or gains a second every 1.4 million years. More advanced NASA’s Deep Space Atomic Clock misses a second once in 10 million years.
India also uses a Cs-133 atomic clock to define the second for timekeeping within its borders.
Cs-133 is a highly stable atom and is naturally found. Hence it is commonly used in atomic clocks.
Optical atomic clocks
Optical atomic clocks are even more accurate. While they have the same working principle, the resonance frequency here is in the optical range.
Radiation in this range includes visible light (to humans) and ultraviolet and infrared radiation.
As part of an optical atomic clock, researchers use lasers to stimulate atomic transitions.
Laser light is highly coherent: the emitted light waves all have the same frequency, and their wavelengths are related to each other in a way that doesn’t change, generating light with more precise properties and great stability.
Higher accuracy
A higher operating frequency is able to measure smaller increments of time more accurately.
Further, optical atomic clocks have much narrower line widths. The narrower the linewidth, the easier it is to tune the frequency of the optical light that produces the resonance, leading to better accuracy.
The linewidth is the range of frequencies over which the transition occurs.
Optical atomic clocks use strontium (Sr), which has narrow line widths and stable optical transitions.
Portable optical atomic clock
Traditional optical atomic clocks are large and not easy to transport.
The new clock’s spectrometer, laser system, and frequency comb are miniaturised for portability.
The new optical atomic clock uses molecular iodine as the frequency standard.
The researchers also equipped the clock with a software control system that could autonomously initialise the clock from an ‘off’ state to a fully operational state.
The optical atomic clocks also had 10x lower long-term drift compared to rubidium atomic clocks.
This means that over long periods, the rate at which the clock’s frequency changes is much lower compared to changes in rubidium atomic clocks.
A frequency comb is a device that generates a series of equally spaced optical frequencies, providing a stable and accurate reference.
Researchers developed a few prototypes, including VIPER (sea applications), PICKLES and EPIC.
Despite the ship’s motion, a temperature fluctuation of 2-3 degrees C, and 4-5% changes in humidity, the clocks were nearly as stable.
Accuracy trade-offs and applications
Atomic clocks are prized for their accuracy, losing or gaining just one second over 300 million years.
Optical atomic clocks only lose or gain a second over 300 billion years.
The new iodine clockisn’t as accurate as an optical atomic clock in the laboratory, trading it off for mobility and robustness. Loses or gains a second only every 9.1 million years.
{GS3 – S&T – Tech} Quantum Science and Technology
Context (TH): UN has designated 2025 as ‘International Year of Quantum Science and Technology’.
The International Year coincides with the 100th anniversary of German physicist Werner Heisenberg‘s pivotal paper, which laid the foundation for quantum mechanics.
The initiative aims to increase global awareness about the importance of quantum science and its applications through year-long, worldwide activities.
National Quantum Mission
The National Quantum Mission (NQM), launched in 2023 (budget – Rs. 6003.65 crore), aims to propel India to the forefront of quantum technology research and development.
The mission’s advancements promise benefits in communication, healthcare, finance,andenergy, impacting drug discovery, space exploration, banking security, and sustainable development.
It supports national initiatives like Digital India,Make in India, Skill India, Stand-up India, Startup India, Self-reliant India, and the Sustainable Development Goals (SDGs).
It is implemented by the Department of Science & Technology.
Objectives
To develop intermediate-scale quantum computers (50-1000 physical qubits) within eight years, leveraging both superconducting andphotonic technologies.
To establish secure communication networks within India and internationally.
To develop high-sensitivity magnetometers using atomic systems and ultra-precise atomic clocks for enhanced timing, communication, and navigation applications.
Thematic Hubs
The NQM will establish four Thematic Hubs (T-Hubs) housed within leading academic and national R&D institutes. Each hub will specialise in a specific area:
Quantum Computing
Quantum Communication
Quantum Sensing & Metrology
Quantum Materials & Devices
Quantum Materials and Devices
This hub aims to design and synthesise novel materials, such as superconductors, advanced semiconductors, and topological materials, for building quantum devices.
Also, single-photon sources/detectors and entangled photon sources should be developed for use in quantum communication, sensing, and metrology.
Quantum Computers
Quantum science and technologies, particularly quantum computers, have gained increasing attention.
Quantum computers are a fundamentally different type of computing technology that harnesses the principles of quantum mechanics to perform calculations.
Quantum computers use quantum bits or “qubits” that can exist as 0, 1, or a quantum superposition (like 0s and 1s in classical computers) of both states simultaneously to perform calculations.
Fully operational quantum computers do not yet exist.
Quantum computers are expected to have transformative effects on electronics, clean energy, and drug development due to their superior computational abilities.
Other Initiatives of the Government of India
National Mission on Quantum Technologies & Applications (NM-QTA)
NMQTA, which aims to promote research, development, and commercialisation of quantum technologies, was announced in the Union Budget 2020-21 with a five-year outlay of Rs. 8000 crore.
Quantum Computing Applications Lab
It was set up by the Ministry of Electronics and Information Technology (MeitY) in 2021 to carry out research towards developing applications using quantum computing.
Quantum Enabled Science & Technology (QuEST) Program
It was initiated by the Department of Science & Technology in 2019 to nucleate, nurture and coordinate efforts in quantum technologies. It also supports research projects across academia and industry in focus areas such as computing, communication, sensing, etc.
Context (DTE): The Iberian Lynx is back from the verge of extinction.
Lynx are medium-sized wildcats found in dense forests across the United States, Europe, and Asia.
They belong to the family Felidae, which includes Bengal tigers, Asiatic lions and Indian leopards.
There are four sub-species of lynx:
Eurasian lynx (L. lynx)
Iberian lynx (L. pardinus)
Canada lynx (L. canadensis)
Bobcat (L. rufus)
About Iberian Lynx
The Iberian lynx is the world’s most endangered feline species.
Distribution: It is native to the Iberian Peninsula in southwestern Europe, including Portugal and Spain.
Habitat: It lives in Mediterranean forests composed of native oaks and abundant undergrowth and thickets. It favours a mixture of dense scrub for shelter and open pasture for hunting.
Physical description: It is heavily spotted and has long legs and a short tail with a black tip. Its coat is tawny with dark spots, and it bears a characteristic “beard” around its face and prominent black ear tufts.
Diet: It feeds on the European rabbit (makes up over 80% of its diet), other small mammals, such as rodents, hares, and birds, as well as larger prey such as deer.
Context (IE):Tmesipteris oblanceolata has the largest known eukaryotic genome on Earth, with 50 times as much DNA as ours. These ferns evolved about 350 million years ago, even before dinosaurs.
It has about 7% larger genome than the Japaneseflowering plant species Paris japonica.
An earlier record was of a plant called Paris japonica, found in the mountains near Nagano, Japan. Its genome contained 148 billion pairs of letters.
The fern called Tmesipteris oblanceolata was found on Grande Terre in New Caledonia.
Epiphytic habit: Grows mainly on the trunks and branches of trees.
Distribution: Oceania and several Pacific Islands, Eastern Australia.
Appearance: 15 to 30 cm long, mostly unbranched, with shorter leaves at the base. The specific adjective “truncata” refers to the leaf tops, which appear abruptly cut off.
Fern
ferns have roots, stems & leaves. However, ferns do not have flowers or seeds.
They usually reproducesexually by tiny spores or sometimes can reproduce vegetatively.
{Prelims – In News} AIM-ICDK Water Challenge 4.0 and Innovations For You
Context (PIB): The Atal Innovation Mission (AIM) has launched two programs to promote sustainability and innovation: AIM – ICDK Water Challenge 4.0 and Innovations For You (5th Edition).
AIM – ICDK Water Challenge 4.0
It is an innovation challenge that focuses on the Indo-Danish Green Strategic Partnership‘s commitment to tackling water-related challenges through creative solutions.
It is a collaboration between AIM and the Innovation Centre Denmark (ICDK).
The challenge, open to students and young entrepreneurs (under 35), has two tracks:
Student Track: “Digital Action for Societal Impact,” focusing on sustainability.
Young Entrepreneurs Track: Platform for startups to accelerate ideas and build global partnerships.
Innovations For You – SDG Entrepreneurs of India (5th Edition)
It is a coffee table book series by AIM that celebrates the efforts of Indian SDG entrepreneurs.
The 5th edition features 60 entrepreneurs driving social progress through sustainable innovations.
Focus Areas:
Recyclable and renewable materials
Green energy
Inclusive education
Supporting underrepresented communities and local artisans
{Prelims – S&T – Defence} JIMEX -24
Context (PIB): The eighth edition of Japan India Maritime Exercise (JIMEX – 24) commenced at Yokosuka, Japan.
The exercise includes both harbour and sea phases.
The harbour phase will comprise professional, sports and social interactions, after which the two navies will jointly hone their war fighting skills at sea and enhance their interoperability through complex multi-discipline operations in the surface, sub-surface and air domains.
Indian Navy’s Indigenous Stealth Frigate INS Shivalik participated in the exercise.
Context (ET): Indian Navy gets fifth Missile-Cum-Ammunition Barge LSAM 13, Yard 81.
These Barges are indigenously designed and built by MSME Shipyard, SECON Engineering Projects Pvt Ltd (SEPPL), Visakhapatnam.
These barges would provide impetus to the operational commitments of the Indian Navy by facilitating transportation, embarkation and disembarkation of articles and ammunition to Indian Navy Ships.
{Prelims – Sci – Bio – Diseases} New Alzheimer’s drug: Donanemab
Context (IE): A committee of independent advisers to the US Food and Drug Administration (FDA) unanimously concluded that the benefits of the new Alzheimer’s drug, Donanemab, outweigh its risks.
Donanemab, like its predecessor Lecanemab, is a monoclonal antibody that targets amyloid beta plaques, a hallmark of Alzheimer’s disease.
Results showed that the drug slowed cognitive decline in early-stage patients by 35.1% over 76 weeks.
Donanemab doesn’t cure the disease. It only slows progression.
The FDA initially withheld approval due to concerns about side effects, like brain swelling and bleeding.
Two abnormal brain structures are hallmarks of Alzheimer’s
Amyloid plaques: Clumps of beta-amyloid proteins that accumulate between neurons.
Neurofibrillary tangles: Twisted strands of tau protein that build up inside neurons.
In 2019, ~3.69 million active cases of Alzheimer’s diseaseand other dementias were in India.
Around 7.4% of Indians over 60 years old have dementia.
India currently lacks a dedicated National Dementia Plan. While dementia is mentioned in existing health plans, it’s not treated as a separate health concern.
Context (DTE | IE): Researchers from the Indian Institute of Technology-Madras (IIT-Madras) and NASA’s Jet Propulsion Laboratory (JPL) have carried out a collaborative study of the behaviour of ‘Superbug’, a multi-drug resistant pathogen aboard the International Space Station (ISS).
Enterobacter bugandensis is a common nosocomial bacterium known for its resistance to multiple drugs.
The study revealed that the strains had mutated and become genetically and functionally distinct from their Earth counterparts due to the unique conditions of space, such as microgravity, radiation, and elevated carbon dioxide levels.
Understanding the resilience of microbial life in the confined and extreme environment of the ISS offers valuable insights into the behaviour of pathogens in analogous settings on Earth, such as hospital intensive care units and surgical theatres and can help combat similar threats on Earth.
Enterobacter species are members of the ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter species) group of pathogens and are on the WHO priority list for developing new antimicrobials.
Context (ET): A recent study found that artificial sweeteners, specifically the sugar substitute xylitol, may pose health risks by leading to blood clots, thereby increasing the risk of serious cardiovascular events such as heart attacks and strokes.
Xylitol is a natural sugar alcohol found in plants, including many fruits and vegetables.
It has a chemical composition similar to that of sugar but with fewer calories.
It is often used as a sugar substitute and is widely used in “sugar-free” chewing gums, mints, and other candies.
Xylitol reduces levels of decay-causing bacteria in saliva,doesn’t spike blood sugar levels and acts against some bacteria that cause ear infections.
High consumption of xylitol can cause a state of hypercoagulability, where the blood has an increased tendency to clot. These clots have the potential to obstruct blood flow in both arteries and veins, leading to serious cardiovascular events.