An inductor, also called a coil, choke, or reactor, is a passive two-terminal electrical component that stores energy in a magnetic field when electric current flows through it. An inductor typically consists of an insulated wire wound into a coil around a core.
Steel is an alloy of iron and carbon, and sometimes other elements. Because of its high tensile strength and low cost, it is a major component used in buildings, infrastructure, tools, ships, automobiles, machines, appliances, and weapons.
Brown is a composite color. In the CMYK color model used in printing or painting, brown is made by combining red, black, and yellow, or red, yellow, and blue. In the RGB color model used to project colors onto television screens and computer monitors, brown is made by combining red and green, in specific proportions. In painting, brown is generally made by adding black to orange. Mixing red-green-blue pigments makes mud color. The brown color is seen widely in nature, in wood, soil, human hair color, eye color and skin pigmentation. Brown is the color of dark wood or rich soil. According to public opinion surveys in Europe and the United States, brown is the least favorite color of the public; the color is most often associated with plainness, the rustic and poverty.
Skin effect is the tendency of an alternating electric current (AC) to become distributed within a conductor such that the current density is largest near the surface of the conductor, and decreases with greater depths in the conductor. The electric current flows mainly at the "skin" of the conductor, between the outer surface and a level called the skin depth. The skin effect causes the effective resistance of the conductor to increase at higher frequencies where the skin depth is smaller, thus reducing the effective cross-section of the conductor. The skin effect is due to opposing eddy currents induced by the changing magnetic field resulting from the alternating current. At 60 Hz in copper, the skin depth is about 8.5 mm. At high frequencies the skin depth becomes much smaller. Increased AC resistance due to the skin effect can be mitigated by using specially woven litz wire. Because the interior of a large conductor carries so little of the current, tubular conductors such as pipe can be used to save weight and cost.
A nail is a horn-like envelope covering the tips of the fingers and toes in most primates and a few other mammals. Nails are similar to claws in other animals. Fingernails and toenails are made of a tough protective protein called alpha-keratin. This protein is also found in the hooves and horns of different animals.
Porphyria cutanea tarda (PCT) is the most common subtype of porphyria. The disease is named because it is a porphyria that often presents with skin manifestations later in life. The disorder results from low levels of the enzyme responsible for the fifth step in heme production. Heme is a vital molecule for all of the body's organs. It is a component of hemoglobin, the molecule that carries oxygen in the blood.
Oni (鬼) are a kind of yōkai, supernatural demon, devils, ogre, or troll in Japanese folklore. They are typically portrayed as hulking figures with one or more horns growing out of their heads. Stereotypically, they are conceived of as red or blue-colored (green-colored), wearing loincloths of tiger pelt, and carrying iron kanabō clubs.
Hypervitaminosis is a condition of abnormally high storage levels of vitamins, which can lead to toxic symptoms. Specific medical names of the different conditions are derived from the vitamin involved: an excess of vitamin A, for example, is called hypervitaminosis A. Hypervitaminoses are primarily caused by fat-soluble vitamins, as these are stored by the body for longer period than the water-soluble vitamins.
Livestock branding is a technique for marking livestock so as to identify the owner. Originally, livestock branding only referred to hot branding large stock with a branding iron, though the term now includes alternative techniques. Other forms of livestock identification include freeze branding, inner lip or ear tattoos, earmarking, ear tagging, and radio-frequency identification (RFID), tagging with a microchip implant. The semi-permanent paint markings used to identify sheep are called a paint or colour brand. In the American West, branding evolved into a complex marking system still in use today.
Stasis dermatitis refers to the skin changes that occur in the leg as a result of "stasis" or blood pooling from insufficient venous return; the alternative name of varicose eczema comes from a common cause of this being varicose veins.
The toggling harpoon is an ancient weapon and tool used in whaling to impale a whale when thrown. Unlike earlier harpoon versions which had only one point, a toggling harpoon has a two-part point. One half of the point is firmly attached to the thrusting base, while the other half of the point is fitted over this first point like a cap and attached to the rest of the point with sinew or another string-like material. When the harpoon is thrust into an animal, the top half of the point detaches and twists horizontally into the animal under the skin, allowing hunters to haul the animal to ship or shore. This harpoon technology lodges the toggling head of the harpoon underneath both the animal's skin and blubber, and instead lodges the point in the muscle, which also prevents the harpoon slipping out.
The Haraldskær Woman is a bog body of a woman found naturally preserved in a bog in Jutland, Denmark, and dating from about 490 BCE. Workers found the body in 1835 while excavating peat on the Haraldskær Estate. The anaerobic conditions and acids of the peat bog contributed to the body's excellent preservation. Not only was the intact skeleton found, but so were the skin and internal organs. Scientists settled disputes about the age and identity of this well preserved body in 1977, when radiocarbon dating determined conclusively that the woman's death occurred around the 5th century BCE.
Koilonychia, also known as spoon nails, is a nail disease that can be a sign of hypochromic anemia, especially iron-deficiency anemia. It refers to abnormally thin nails which have lost their convexity, becoming flat or even concave in shape. In a sense, koilonychia is the opposite of nail clubbing. In early stages nails may be brittle and chip or break easily.
The Asanbosam, Asasabonsam or more commonly Sasabonsam is a vampire-like folkloric being from the Asante people. It belongs to the folklore of the Ashanti of southern Ghana, as well as Côte d'Ivoire, Togo and 18th century Jamaica from enslaved Asantes. It is said to have iron teeth, pink skin, long red hair and iron hooks for feet and lives in trees, attacking from above.
Pathogenic bacteria are bacteria that can cause disease. This article deals with human pathogenic bacteria. Although most bacteria are harmless or often beneficial, some are pathogenic, with the number of species estimated as fewer than a hundred that are seen to cause infectious diseases in humans. By contrast, several thousand species exist in the human digestive system.
Schamberg's disease, is a chronic discoloration of the skin found in people of all ages, usually affecting the legs. It slowly spreads throughout the body, and is most common in males. It is named after Jay Frank Schamberg, who described it in 1901. There is no known cure for this disease and it is not a life-threatening condition. The skin lesions may cause itching, which can be treated by applying cortisone cream. The cortisone cream will only help with the itching and the discoloration of the skin will remain, which may cause a cosmetic concern in the future. Schamberg's disease is usually asymptomatic meaning that it shows no signs of this condition, except for the discoloration of the skin. This condition is caused by leaky blood vessels, where red blood cells escape near the surface of skin and release iron into the surrounding tissue. The cause of the leaky capillaries is unknown.
Staining of the nail plate may occur due to nicotine, dyes, potassium permanganate, mercury compounds, hydroquinone, elemental iron, mepacrine, photographic developer, anthralin, chrysarobin, glutaraldehyde, or resorcin.
Platonychia is characterized by an abnormally flat and broad nail, and may be seen as part of an autosomal-dominant condition in which multiple nail abnormalities are present in many members of a large family. Seen in iron deficiency condition.
Drug induced pigmentation may take on many different appearances, one of the most common being a change in the color, or pigmentation, of the skin.
