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Wilmington, North Carolina once had a thriving Black middle class and an elected interracial government. In 1898 white supremacists used violence to overthrow that government, kill Black residents and drive many others from the city.
MORE →Reflects the personal views, recollections, and perspective of the author, Mike Davis.
This is a personal recollection on the Move fire on May 13, 1985
 | This article may be confusing or unclear to readers. (December 2017) |
Precursorism (called in its more extreme forms precursoritis[1] or precursitis) is historiographical bias in which a historian seeks direct precursors of present-day institutions or ideas in earlier historical periods, where none may clearly exist. Precursorist historical narratives are anachronistic: cherry picking data and often failing to account for the perspectives of people in the contemporary past. Precursorism is considered to be a form of Whig history, and is a special problem among historians of science.[2]
It is now commonly assumed that historians of science should study past scientific "ideas in their own right, avoiding anachronism and precursoritis."[3]
The French historian of medieval science, Pierre Duhem, exemplifies several of the characteristics of the quest for precursors of modern scientific ideas. Duhem was trained as a physicist, rather than as a historian; he was French and many of the precursors he identified were French or studied at the University of Paris; he was a devout Catholic and many of the precursors of the theologically troubling Italian, Galileo, were members of religious orders. Most striking among them was the French bishop and scholastic philosopher, Nicole Oresme.[4]
The concept has been applied to those who would find precursors of Darwin in the early nineteenth century,[5] and to those who would find anticipations of modern science in ancient cultures from the Near East to Mesoamerica.[1] Precursorism has recently been identified as a significant factor in some studies of the work of Islamic scientists.[6]
In 2018, Hans-Johann Glock identified precursorism as a tendency among analytic philosophers who study the history of philosophy. He describes the tendency as "a veritable fetishism of alleged or actual intellectual precursors" and "a déformation professionnelle, which afflicts... historians and philosophers". Glock describes a handful of contemporary analytical philosophers as interpreting certain historical western philosophers ahistorically; possessing philosophical beliefs which align with modern philosophical schools that did not exist during their lifetimes. Additionally, Glock recalls moments when living analytical philosophers "resisted attempts to co-opt them into various historical schools [of philosophy]".[7]
Source: Wikipedia. Article content is retrieved live through the MediaWiki API.
Precursorism (called in its more extreme forms precursoritis or precursitis) is historiographical bias in which a historian seeks direct precursors of present-day institutions or ideas in earlier historical periods, where none may clearly exist. Precursorist historical narratives are anachronistic: cherry picking data and often failing to account for the perspectives of people in the contemporary past. Precursorism is considered to be a form of Whig history, and is a special problem among historians of science. It is now commonly assumed that historians of science should study past scientific "ideas in their own right, avoiding anachronism and precursoritis."
A hormone (from Ancient Greek ὁρμῶν (hormôn) 'setting in motion') is a class of signaling molecules in multicellular organisms that are sent to distant organs or tissues by complex biological processes to regulate physiology and behavior. Hormones are required for the normal development of animals, plants and fungi. Due to the broad definition of a hormone (as a signaling molecule that exerts its effects far from its site of production), numerous kinds of molecules can be classified as hormones. Substances that can be considered hormones include eicosanoids (e.g. prostaglandins and thromboxanes), steroids (e.g. oestrogen and brassinosteroid), amino acid derivatives (e.g. epinephrine and auxin), protein or peptides (e.g. insulin and CLE peptides), and gases (e.g. ethylene and nitric oxide). Hormones are used to communicate between organs and tissues. In vertebrates, hormones are responsible for regulating a wide range of processes including both physiological processes and behavioral activities such as digestion, metabolism, respiration, sensory perception, sleep, excretion, lactation, stress induction, growth and development, movement, reproduction, and mood manipulation. In plants, hormones modulate almost all aspects of development, from germination to senescence. Hormones affect distant cells by binding to specific receptor proteins in the target cell, resulting in a change in cell function. When a hormone binds to the receptor, it results in the activation of a signal transduction pathway that typically activates gene transcription, resulting in increased expression of target proteins. Hormones can also act in non-genomic pathways that synergize with genomic effects. Water-soluble hormones (such as peptides and amines) generally act on the surface of target cells via second messengers. Lipid soluble hormones, (such as steroids) generally pass through the plasma membrane of target cells (both cytoplasmic and nuclear) to act within their nuclei. Brassinosteroids, a type of polyhydroxysteroids, are a sixth class of plant hormones and may be useful as an anticancer drug for endocrine-responsive tumors to cause apoptosis and limit plant growth. Despite being lipid soluble, they nevertheless attach to their receptor at the cell surface. In vertebrates, endocrine glands are specialized organs that secrete hormones into the endocrine signaling system. Hormone secretion occurs in response to specific biochemical signals and is often subject to negative feedback regulation. For instance, high blood sugar (serum glucose concentration) promotes insulin synthesis. Insulin then acts to reduce glucose levels and maintain homeostasis, leading to reduced insulin levels. Upon secretion, water-soluble hormones are readily transported through the circulatory system. Lipid-soluble hormones must bind to carrier plasma glycoproteins (e.g., thyroxine-binding globulin (TBG)) to form ligand-protein complexes. Some hormones, such as insulin and growth hormones, can be released into the bloodstream already fully active. Other hormones, called prohormones, must be activated in certain cells through a series of steps that are usually tightly controlled. The endocrine system secretes hormones directly into the bloodstream, typically via fenestrated capillaries, whereas the exocrine system secretes its hormones indirectly using ducts. Hormones with paracrine function diffuse through the interstitial spaces to nearby target tissue. Plants lack specialized organs for the secretion of hormones, although there is a spatial distribution of hormone production. For example, the hormone auxin is produced mainly at the tips of young leaves and in the shoot apical meristem. The lack of specialised glands means that the main site of hormone production can change throughout the life of a plant, and the site of production is dependent on the plant's age and environment.
John the Baptist (c. 6 BC – c. AD 30) was an itinerant Jewish preacher (Hebrew name Yochanan) who was active in the area of the Jordan River in the early 1st century AD. Sometimes referred to as John the Baptizer, he is known as Saint John the Forerunner in Eastern Orthodoxy, Eastern Catholicism, and Oriental Orthodoxy, as Saint John the Immerser in the Baptist tradition, and as the prophet Yahya ibn Zakariya in Islam. John the Baptist is revered as a major religious figure in Christianity, Islam, the Baháʼí Faith, the Druze faith, and Mandaeism; in the last of these he is considered to be the final and most vital prophet. He is regarded as a prophet of God by all of the aforementioned faiths, and is honoured as a saint in many Christian denominations. According to the New Testament, John anticipated a messianic figure greater than himself; in the Gospels, he is portrayed as the precursor or forerunner of Jesus. According to the Gospel of Matthew, Jesus himself identifies John as "Elijah who is to come", which is a direct reference to the Book of Malachi (Malachi 4:5), as confirmed by the angel Gabriel, who announced John's birth to his father Zechariah. According to the Gospel of Luke, John and Jesus were relatives. Some scholars think that John belonged to the Essenes, a semi-ascetic Jewish sect who expected a messiah and practised ritual baptism. John used baptism as the central symbol or sacrament of his pre-messianic movement. The majority of biblical scholars agree that John baptized Jesus, and several New Testament accounts report that some of Jesus's early followers had previously been followers of John. According to the New Testament, John the Baptist was sentenced to death by Herod Antipas and subsequently beheaded around AD 30, after John rebuked him for divorcing his wife and then unlawfully wedding Herodias, the wife of his brother Herod Philip I. The Roman historian Josephus also mentions John in his Antiquities of the Jews, and states that he was executed by order of Herod Antipas in the fortress at Machaerus. Followers of John persisted into the second century AD, and some proclaimed him to be the Messiah awaited by Jews. In modern times, the followers of John the Baptist are the Mandaeans, an ancient ethnoreligious group who believe that he is their greatest and final prophet. In Catholic martyrology, John is the only saint whose birth and death are both commemorated.
In nuclear physics, a decay product (also known as a daughter product, daughter isotope, radio-daughter, or daughter nuclide) is the remaining nuclide left over from radioactive decay. Radioactive decay often proceeds via a sequence of steps (decay chain). For example, 238U decays to 234Th which decays to 234mPa which decays, and so on, to 206Pb (which is stable): U 238 ⟶ Th 234 ⏟ daughter of 238 U ⟶ Pa 234 m ⏟ granddaughter of 238 U ⟶ ⋯ ⟶ Pb 206 ⏞ decay products of 238 U {\displaystyle {\ce {^{238}U->}}\overbrace {\underbrace {\ce {^{234}Th}} _{\ce {daughter~of~^{238}U}}{\ce {->}}\underbrace {\ce {^{234\!m}Pa}} _{\ce {granddaughter~of~^{238}U}}{\ce {->\cdots ->{^{206}Pb}}}} ^{\ce {decay~products~of~^{238}U}}} In this example: 234Th, 234mPa,...,206Pb are the decay products of 238U. 234Th is the daughter of the parent 238U. 234mPa (234 metastable) is the granddaughter of 238U. These might also be referred to as the daughter products of 238U. Decay products are important in understanding radioactive decay and the management of radioactive waste. For elements above lead in atomic number, the decay chain typically ends with an isotope of lead or bismuth. Bismuth itself decays to thallium, but the decay is so slow as to be practically negligible. In many cases, individual members of the decay chain are as radioactive as the parent, but far smaller in volume/mass. Thus, although uranium is not dangerously radioactive when pure, some pieces of naturally occurring pitchblende are quite dangerous owing to their radium-226 content, which is soluble and not a ceramic like the parent. Similarly, thorium gas mantles are very slightly radioactive when new, but become more radioactive after only a few months of storage as the daughters of 232Th build up. Although it cannot be predicted whether any given atom of a radioactive substance will decay at any given time, the decay products of a radioactive substance are extremely predictable. Because of this, decay products are important to scientists in many fields who need to know the quantity or type of the parent product. Such studies are done to measure pollution levels (in and around nuclear facilities) and for other matters.
Before the 1921 destruction of Tulsa’s Greenwood District, Black residents had created a remarkable center of business and community life. The district included stores, professional offices, entertainment venues and homes owned by Black citizens. Understanding Greenwood means learning what was built—not only what was burned.
MORE →The Greenwood District.