Engineering & Science

The human neck is far more complex than it appears from the outside. Beneath the skin are several carefully arranged layers that protect and support important structures. The outermost skin contains sensory nerves, hair follicles, sweat glands, oil glands and small blood vessels. Underneath is the subcutaneous tissue, which contains varying amounts of fat, lymphatic vessels, nerves and blood vessels. This layer provides cushioning and allows the skin to move over deeper tissues. Within the superficial fascia is the platysma, a thin sheet-like muscle extending from the upper chest toward the lower face. It helps move the skin of the neck and lower face.

Deeper inside is the deep cervical fascia, a strong network of connective tissue that surrounds, separates and supports structures throughout the neck. It includes the investing fascia around muscles such as the sternocleidomastoid and trapezius, the pretracheal fascia surrounding structures in the front of the neck, and the prevertebral fascia surrounding the cervical spine and deep muscles. The carotid sheath is another important fascial structure. It surrounds the carotid artery, internal jugular vein and vagus nerve. These fascial layers also create spaces between tissues, which provide pathways for nerves and vessels and can sometimes allow infections or fluid to spread.

Within and beneath these layers are numerous muscles, blood vessels and nerves. The neck muscles include the sternocleidomastoid, trapezius, scalene muscles, levator scapulae, prevertebral muscles, and the suprahyoid and infrahyoid muscle groups. These muscles help control head movement, posture, swallowing and speech. Major blood vessels include the carotid arteries, which carry blood toward the brain, and the internal jugular veins, which return blood toward the heart. Important nerves include the vagus nerve, phrenic nerve, cervical plexus and sympathetic trunk. The neck also contains lymph nodes and lymphatic vessels that are part of the body's immune system.

At deeper levels are the thyroid and parathyroid glands, larynx, trachea and esophagus. The thyroid helps regulate metabolism through hormone production, while the parathyroid glands help control calcium levels. The larynx is involved in breathing and producing sound, while the trachea carries air toward the lungs and the esophagus transports swallowed food toward the stomach. At the deepest region are the prevertebral muscles, cervical vertebrae and spinal cord. The spinal cord passes through the protected vertebral canal and is surrounded by the meninges and cerebrospinal fluid. Together, these layers form a highly organized three-dimensional system that allows the neck to move while protecting vital organs, nerves, blood vessels and the connection between the brain and the rest of the body.

A new chatbot called ChatTJB has attracted attention in San Francisco by presenting itself as an AI-powered service, while revealing that its supposed artificial intelligence is actually one person, Tucker Bryant. The project is a playful experiment designed to make people question how readily they trust and rely on AI.

Bryant, an artist, Stanford graduate and former Google employee, personally reads and answers questions submitted through the ChatTJB website. Rather than using a conventional artificial intelligence model, the service turns Bryant into a one-person version of a chatbot. On the website, AI humorously stands for “average individual.”

The project was promoted through a $6,000 billboard in San Francisco that was deliberately designed to resemble a professional AI advertisement. The billboard helped the unusual concept gain widespread attention online.

Bryant said the project was created to recreate the polished appearance of modern chatbot services while providing an intentionally ordinary or sometimes poor experience. His goal was to encourage people to think more carefully about the answers they receive from automated systems instead of accepting them without question.

After photos of the billboard spread online, the number of questions submitted to ChatTJB reportedly increased dramatically. Bryant said he was receiving as many as 5,000 requests per hour at one point and had answered more than 30,000 questions.

The service works exactly as its joke suggests: users submit questions, Bryant reads them, thinks about the response and replies when he is awake and motivated. This means there is no traditional AI system generating the answers.

The growing workload has led Bryant to consider turning ChatTJB into a community project. He has begun looking for other “average individuals” who could help answer questions. The platform has introduced measures including an onboarding quiz, message triage and crisis-response resources.

ChatTJB’s unusual success offers a humorous commentary on the AI boom, while highlighting how convincing the appearance of an automated chatbot can be even when a human is behind every response.

Mariangela Hungria, a Brazilian scientist at Embrapa, spent more than four decades researching beneficial soil bacteria and their potential to reduce agriculture’s dependence on synthetic nitrogen fertilisers. Her work helped transform soybean farming in Brazil and earned her the 2025 World Food Prize.

Nitrogen is essential for plants because it is needed to produce proteins, enzymes and chlorophyll. Although the atmosphere contains abundant nitrogen, most plants cannot use it directly. Farmers have traditionally relied on synthetic fertilisers to provide usable nitrogen, but producing these fertilisers requires significant energy and can contribute to pollution, greenhouse-gas emissions and high farming costs.

Hungria focused on biological nitrogen fixation, a natural process in which certain bacteria convert atmospheric nitrogen into a form plants can use. In soybean plants, these bacteria live in small nodules attached to the roots. The plant supplies the bacteria with nutrients, while the bacteria provide nitrogen to the plant.

Her achievement was not discovering this natural process. Instead, she identified and improved highly effective bacterial strains suited to Brazil’s tropical soils and helped demonstrate that they could reliably work on farms at commercial scale.

Working through Embrapa’s soybean research programmes, Hungria and her colleagues developed microbial inoculants that farmers could apply to soybean seeds before planting. These products allowed crops to obtain much of their nitrogen biologically, greatly reducing the need for synthetic nitrogen fertiliser.

The technology was adopted across millions of hectares of Brazilian farmland. It helped farmers lower input costs and reduced Brazil’s dependence on imported nitrogen fertilisers while supporting high soybean production. The approach also helped reduce environmental impacts associated with conventional fertiliser use.

Her work has gained international attention because biological nitrogen fixation could offer useful solutions as farmers face rising fertiliser costs and growing pressure to reduce agricultural emissions.

Hungria’s research demonstrates how agriculture can use living biological systems rather than relying entirely on industrial chemicals. Her work, particularly with soybeans, has become an important example of how microbes can contribute to more sustainable farming and food production.

Eye mucus may seem like an unpleasant substance, especially when it collects in the corners of your eyes after sleeping, but it actually plays an important role in keeping your eyes clean, moist and protected.

The surface of the eye is constantly exposed to the outside environment. Dust, smoke, tiny particles and dead skin cells can come into contact with it throughout the day. Mucus helps trap some of these unwanted particles, preventing them from remaining on the delicate surface of the eye and potentially causing irritation.

Eye mucus also works together with tears and oils produced by the eyelids to keep the eyes properly lubricated. This protective layer helps maintain a smooth, moist surface, which is important for comfortable vision and normal eye function. Without sufficient lubrication, the eyes can become dry, irritated or uncomfortable.

Blinking is another important part of the eye’s natural cleaning system. Every time you blink, your eyelids spread tears and mucus across the surface of the eye. This movement helps collect and remove particles and waste, gradually carrying them toward the corners of the eyes and through the tear drainage system.

The process changes while you sleep. Because you are not blinking, mucus, oils, tears and trapped particles can accumulate around the edges of your eyelids. After waking, this dried material may appear as small crusts or “sleep” in the corners of your eyes. In most cases, this is a normal part of the eye’s cleaning and protective process.

However, not all eye discharge is harmless. A sudden increase in discharge, especially if it is thick, yellow or green, or accompanied by redness, swelling, pain, itching or changes in vision, can sometimes indicate an eye infection or another condition.

Overall, eye mucus is not simply waste. It forms part of the eye’s natural defence and cleaning system, helping trap debris, maintain moisture and remove unwanted material from the delicate surface of the eyes.

Reindeer have a remarkable adaptation that changes the colour of their eyes with the seasons. Their eyes appear golden during summer but become a deep blue in winter, helping them cope with the extreme changes in Arctic light.

The colour-changing part is the tapetum lucidum, a reflective layer located behind the retina. It helps animals see in low-light conditions by reflecting light back through the retina, giving light-sensitive cells another opportunity to detect it.

During the Arctic summer, reindeer experience almost continuous daylight, while winter brings months of darkness. During these dark months, their pupils remain widely dilated for long periods to allow as much light as possible into the eyes.

Researchers led by neuroscientist Glen Jeffery studied reindeer eyes collected from animals that had been killed during different seasons. They found that the tapetum lucidum was golden in summer specimens but deep blue in winter specimens.

Scientists believe that prolonged pupil dilation during winter may increase pressure inside the eye. This pressure can squeeze the fluid between collagen fibres within the tapetum. As the fibres become more tightly packed, they reflect different wavelengths of light, causing the tapetum to appear blue rather than golden.

Researchers also found that winter reindeer eyes were dramatically more sensitive to light. However, scientists have debated whether the change in tapetum colour alone can explain this huge increase in sensitivity. Some researchers suggest that changes within the retina, including light-sensitive pigments, may also play an important role.

Evidence from reindeer kept near artificial lights provided additional clues. Their pupils did not dilate as much during winter, and their tapetum became partly green rather than completely blue. Their eyes were also less sensitive than those of reindeer exposed to much darker conditions.

The findings show how remarkably adaptable reindeer vision can be. Their seasonal eye changes appear to help them cope with extreme Arctic lighting, although scientists continue to investigate exactly how the changes in eye structure and retinal sensitivity are connected.

Lukas Sjoman a Finnish adventurer has demonstrated the possibilities of solar-powered travel by completing a long-distance voyage aboard a yacht he designed and built himself. His vessel, Helios 11, relies on sunlight rather than conventional petrol or diesel fuel for its journeys.

Sjoman spent approximately 200 days building the yacht, carefully designing it to operate independently while making use of renewable energy. The vessel is equipped with solar panels that capture sunlight and convert it into electricity. That stored and generated power is then used to operate the yacht’s equipment and propel it across the water.

One of the biggest advantages of the setup is that the yacht does not need conventional fuel stops. As long as there is sufficient sunlight and the boat has enough stored energy, Sjoman can continue traveling without depending on marinas for regular refuelling. This gives him greater freedom during long voyages while reducing reliance on fossil fuels.

In one of his recent journeys, Sjoman traveled approximately 3,106 miles, sailing from Finland toward Spain and reaching destinations including Ibiza. The expedition provided a significant real-world test of Helios 11 and its ability to cover long distances while relying primarily on solar energy.

Sjoman has documented much of his work and his adventures through his YouTube channel. His videos feature the yacht’s construction, modifications, technical improvements and experiences at sea. His earlier adventures have also included experimental journeys through frozen canals in France, showing how the unusual vessel can be adapted to challenging environments.

The voyage also brought an unexpected problem. While the yacht was anchored near La Rápita, Spain, Sjoman discovered that his utility dinghy had been stolen. The small boat was essential because it provided transportation between Helios 11 and the shore.

Without the dinghy, collecting supplies and reaching land became considerably more difficult. Helios 11 was too large to simply pull onto shallow beaches or use conveniently at very small harbours.

Rather than allowing the setback to end the expedition, Sjoman and his crew came up with an alternative. They constructed an emergency replacement catamaran dinghy, restoring their ability to travel between the yacht and shore.

Sjoman’s experience combines renewable energy, practical engineering and problem-solving. His journey with Helios 11 demonstrates how solar technology can be used for extended marine travel while highlighting the potential for more independent and environmentally conscious exploration.

A common octopus holds a remarkable Guinness World Records title for having the greatest known number of arms. The extraordinary specimen was captured alive in December 1998 in Matoya Bay, Japan.

Octopuses normally have eight arms, although they are sometimes incorrectly called tentacles. However, this particular octopus was very different. Each of its eight original arms had branched repeatedly, creating numerous additional limbs. As a result, the animal had an astonishing 96 arms in total.

The unusual octopus survived for approximately five months after being captured and kept in captivity. Following its death, its body was preserved and placed on permanent display at the Shima Marineland Aquarium in Shima, Japan.

The case is an unusual example of a developmental abnormality in an octopus. While octopuses generally develop eight arms, specimens with fewer or more arms have occasionally been documented. The Japanese specimen was particularly extraordinary because the additional limbs resulted from branching of its normal arms, producing an appearance very different from that of an ordinary octopus.

Its 96-limb count made it a remarkable record-holder and attracted attention because of how unusual the animal’s body structure was. Rather than simply having additional arms developing independently, its original arms had divided into many branches.

The record demonstrates the unusual biological variations that can sometimes occur in marine animals. Although such abnormalities are extremely rare, they can produce striking differences from the normal body structure of a species.

According to Guinness World Records, records can change and may not always be immediately published online. The organisation lists this specimen as the holder of the record for the octopus with the most arms.

The unusual animal remains remembered for its extraordinary anatomy: a common octopus from Matoya Bay, Japan, captured in 1998, with an incredible 96 limbs. It is one of the most unusual examples of natural variation ever recorded in an octopus.

Medical imaging allows doctors to look inside the body without surgery. Different imaging techniques are designed to show different tissues and problems. X-rays, MRI scans, and CT scans are among the most commonly used methods, but each works differently and has particular strengths.

An X-ray uses a small amount of ionizing radiation to create images of structures inside the body. It is particularly useful for examining bones, because dense tissues absorb more X-rays and appear brighter on the resulting image.

X-rays are commonly used when doctors suspect a fracture, dislocation, or other bone abnormality. They can also help identify certain infections or changes in the lungs. For example, a chest X-ray may reveal signs associated with pneumonia, fluid buildup, or other lung problems.

X-rays are generally quick and widely available. A typical examination takes only a few minutes. However, because X-rays provide relatively flat, two-dimensional images, they may not show certain soft-tissue injuries clearly. Very small fractures or complicated injuries can sometimes require additional imaging.

Magnetic resonance imaging (MRI) creates detailed images using a strong magnetic field and radio waves rather than ionizing radiation. One of its biggest advantages is its ability to distinguish between different types of soft tissue.

MRI is especially useful for examining the brain, spinal cord, muscles, tendons, ligaments, joints, and many internal organs. For example, doctors may use an MRI to investigate ligament injuries in the knee, abnormalities in the brain, spinal problems, or certain organ conditions.

MRI can produce highly detailed images in multiple directions, allowing physicians to examine structures from different angles. It is particularly valuable when an injury or disease involves tissues that may be difficult to evaluate with a standard X-ray.

However, MRI examinations generally take longer than X-rays and can be noisy. Patients must remain relatively still inside the scanner. Certain implanted medical devices or metal objects may also require special consideration before an MRI.

A computed tomography (CT) scan uses X-rays and computer processing to create detailed cross-sectional images of the body. Instead of producing just one flat image, a CT scanner takes numerous images from different angles and combines them to create detailed slices and, when needed, three-dimensional views.

CT scans are particularly useful for detecting complex bone fractures, internal bleeding, organ injuries, and other urgent conditions. They are frequently used after serious accidents because they can quickly provide detailed information about injuries inside the body.

CT imaging can also help doctors evaluate the chest, abdomen, pelvis, head, and blood vessels. Its speed makes it especially valuable in emergency situations.

In simple terms, X-rays are fast and excellent for many bone and chest examinations; MRI provides superior detail for many soft tissues; and CT combines speed with highly detailed cross-sectional images, making it especially useful for trauma and complex internal injuries. The most appropriate scan depends on the patient's symptoms, suspected condition, and the information the doctor needs.