The down quark or d quark is the second-lightest of all quarks, a type of elementary particle, and a major constituent of matter. Together with the up quark, it forms the neutrons and protons of atomic nuclei. It is part of the first generation of matter, has an electric charge of −¹⁄3 e and a bare mass of 4.1–5.7 MeV/c². Like all quarks, the down quark is an elementary fermion with spin-¹⁄2, and experiences all four fundamental interactions: gravitation, electromagnetism, weak interactions, and strong interactions. The antiparticle of the down quark is the down antiquark, which differs from it only in that some of its properties have equal magnitude but opposite sign.
Its existence was postulated in 1964 by Murray Gell-Mann and George Zweig to explain the Eightfold Way classification scheme of hadrons. The down quark was first observed by experiments at the Stanford Linear Accelerator Center in 1968.

Necessitous generally refers to being in extreme poverty or lacking the basic necessities of life; being in a condition where one is in dire need or urgent requirement of something. It implies a state of impoverishment or great distress due to unfulfillment of essential needs or unmet demands.

A three-pronged dart for striking fish, used in the north of
England.

Botulinus, also known as Clostridium botulinum, is a bacterium that produces a neurotoxin known as botulinum toxin. This toxin is extremely dangerous and can cause a life-threatening illness called botulism, characterized by muscle paralysis. However, in small controlled amounts, botulinum toxin is commonly used in medical and cosmetic procedures, such as Botox injections.

The European Hackberry, also known as Celtis australis, is a deciduous tree native to southern Europe, North Africa, and Asia Minor. It typically grows to about 20-25 meters tall and is characterized by its smooth, gray bark, serrated, glossy dark green leaves, and small berry-like fruits that turn from green to dark purple when ripe. The tree is commonly used as an ornamental tree in landscaping due to its tolerance for urban conditions and resistance to pests. In addition, the wood of the European Hackberry is highly valued for its hardness and durability.

Enterobius vermicularis, also known as the pinworm or threadworm, is a parasitic roundworm that primarily infects humans. It is one of the most common types of intestinal parasites, known for causing the medical condition Enterobiasis especially in children. Adult worms typically reside in the colon and rectum, whereas the eggs are laid around the anus which can cause itching and discomfort. The infection is usually spread by ingesting these microscopic eggs, often due to poor hygiene or contact with contaminated objects or surfaces.

Disorganisation is a state or condition where things are not properly arranged or managed, resulting in confusion or disorder. It can refer to the lack of structure or order in physical spaces, thoughts, actions, or systems, often leading to inefficiency, mistakes, or chaos.

A common wart, also known as verruca vulgaris, is a small, often hard, noncancerous growth on the skin that is caused by an infection with certain strains of the human papillomavirus (HPV). They can appear anywhere on the body but are frequently found on hands and feet. The appearance of common warts can vary, typically rough, round, or oval shaped and grey, brown, or yellowish in color. The size can also vary. They are generally harmless, but can cause discomfort or embarrassment due to their appearance. Transmission often occurs through direct contact with an infected person or indirectly in environments such as public showers or pools.

The genus Miltonia refers to a group of orchids, commonly known as pansy orchids due to their resemblance to pansy flowers. They are native to tropical regions of Central and South America. The plants are epiphytic, which means they grow on other plants, usually trees, but are not parasitic. Miltonia orchids are known for their vibrant colors, unique patterns, and fragrant scents. They are popular in horticulture due to their appealing and distinctive appearance.

A goldmine is a location, site or place where gold is obtained by mining operations, often through digging into the earth or rock. It can also be metaphorically used to refer to any source of abundant or profitable business or wealth.

a type of thick jacket, usually dark blue, often worn by men who work outside

Heat of dissociation is the amount of heat energy required to break apart a specific chemical compound into its individual parts or elements. It is usually expressed in joules per mole or calories per mole. The heat of dissociation is positive if the process is endothermic (absorbs heat) and negative if it is exothermic (releases heat).

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Law merchant, also known as lex mercatoria, refers to a body of commercial law used by merchants throughout Europe during the medieval period. It is a system of law that evolved based on common trade practices and customs among traders, which was eventually adopted into national and international law. This system includes principles and rules related to transactions, contracts, payment systems, bills of exchange, partnerships and other issues related to commerce.

The Philippine peso, often denoted by the symbol ₱, is the official currency of the Philippines. It is subdivided into 100 centavos or sentimos in Filipino. The Central Bank of the Philippines, known as Bangko Sentral ng Pilipinas, is in charge of issuing, handling, and regulating the Philippine peso. Its exchange rate with other currencies varies and is determined by the foreign exchange market.

Genus Halogeton is a small group of plant species belonging to the family Amaranthaceae. The most well-known species within this genus is Halogeton glomeratus, commonly known as halogeton or saltlover. These plants are characterized by their ability to grow in saline or alkaline soils, making them well-adapted to desert or semi-arid environments. They are typically annual herbs with fleshy, often jointed stems and small, inconspicuous flowers. Although some species within this genus can be toxic to grazing animals due to their high oxalate content.

Catastrophe is a short play by Samuel Beckett, written in French in 1982 at the invitation of A.I.D.A. and “[f]irst produced in the Avignon Festival … Beckett considered it ‘massacred.’” It is one of his few plays to deal with a political theme and, arguably, holds the title of Becketts most optimistic work. It was dedicated to then imprisoned Czech reformer and playwright, Václav Havel.