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1811 In Science
The year 1811 in science and technology involved some significant events, listed below. Astronomy * March 25 – Great Comet discovered by Honoré Flaugergues. Biology * Johann Karl Wilhelm Illiger publishes ''Prodromus systematis mammalium et avium'', an updating of Linnean taxonomy and a major influence on the concept of the 'Family' in biology. He first defines the infraclass ''Marsupialia''. * Peter Simon Pallas begins publication of ''Zoographia rosso-Asiatica, sistens omnium animalium in extenso Imperio rossico, et adjacentibus maribus observatorum recensionem, domicilia, mores et descriptiones, anatomen atque icones plurimorum'' in Saint Petersburg. Chemistry * Bernard Courtois discovers iodine. * Joseph Louis Gay-Lussac and Louis Jacques Thénard publish ''Recherches Physico-Chimiques, faites sur la pile; sur la préparation chimique et les propriétés du potassium et du sodium; sur la décomposition de l'acide boracique; sur les acides fluorique, muriatique et muri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amedeo Avogadro
Lorenzo Romano Amedeo Carlo Avogadro, Count of Quaregna and Cerreto (, also , ; 9 August 17769 July 1856) was an Italian scientist, most noted for his contribution to molecular theory now known as Avogadro's law, which states that equal volumes of gases under the same conditions of temperature and pressure will contain equal numbers of molecules. In tribute to him, the ratio of the number of elementary entities (atoms, molecules, ions or other particles) in a substance to its amount of substance (the latter having the unit mole), , is known as the Avogadro constant. This constant is denoted ''N''A, and is one of the seven defining constants of the SI. Biography Amedeo Avogadro was born in Turin to a noble family of the Kingdom of Sardinia (now part of Italy) in the year 1776. He graduated in ecclesiastical law at the late age of 20 and began to practice. Soon after, he dedicated himself to physics and mathematics (then called ''positive philosophy''), and in 1809 starte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dublin
Dublin is the capital and largest city of Republic of Ireland, Ireland. Situated on Dublin Bay at the mouth of the River Liffey, it is in the Provinces of Ireland, province of Leinster, and is bordered on the south by the Dublin Mountains, part of the Wicklow Mountains range. Dublin is the largest city by population on the island of Ireland; at the 2022 census of Ireland, 2022 census, the city council area had a population of 592,713, while the city including suburbs had a population of 1,263,219, County Dublin had a population of 1,501,500. Various definitions of a metropolitan Greater Dublin Area exist. A settlement was established in the area by the Gaels during or before the 7th century, followed by the Vikings. As the Kingdom of Dublin grew, it became Ireland's principal settlement by the 12th century Anglo-Norman invasion of Ireland. The city expanded rapidly from the 17th century and was briefly the second largest in the British Empire and sixth largest in Western Europ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abraham Colles
Abraham Colles (23 July 1773 – 16 November 1843) was an Irish surgeon and physician who served as Professor of Anatomy, Surgery and Physiology at the Royal College of Surgeons in Ireland, Royal College of Surgeons in Ireland (RCSI) and the President of the RCSI in 1802 and 1830. A prestigious Colles Medal & Travelling Fellowship in Surgery is awarded competitively annually to an Irish surgical trainee embarking on higher specialist training abroad before returning to establish practice in Ireland. Life Descended from a Worcestershire family, some of whom had sat in Parliament, he was born to William Colles and Mary Anne Bates of Woodbroak, County Wexford. The family lived near Millmount, a townland near Kilkenny, Ireland, where his father owned and managed his inheritance which was the extensive Black Quarry that produced the famous Black Kilkenny Marble. His father died when Colles was 6, but his mother took over the management of the quarry and managed to give her children ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motor Nerve
A motor nerve, or efferent nerve, is a nerve that contains exclusively efferent nerve fibers and transmits motor signals from the central nervous system (CNS) to the effector organs (muscles and glands), as opposed to sensory nerves, which transfer signals from sensory receptors in the periphery to the CNS. This is different from the motor neuron, which includes a cell body and branching of dendrites, while the nerve is made up of a bundle of axons. In the strict sense, a "motor nerve" can refer exclusively to the connection to muscles, excluding other organs. The vast majority of nerves contain both sensory and motor fibers and are therefore called mixed nerves. Structure and function Motor nerve fibers Transduction (physiology), transduce signals from the CNS to peripheral neurons of proximal muscle tissue. Motor nerve axon terminals innervate Skeletal muscle, skeletal and Smooth muscle tissue, smooth muscle, as they are heavily involved in muscle control. Motor nerves tend t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sensory Nerve
A sensory nerve, or afferent nerve, is a nerve that contains exclusively afferent nerve fibers. Nerves containing also motor fibers are called mixed nerve, mixed. Afferent nerve fibers in a sensory nerve carry sensory system, sensory information toward the central nervous system (CNS) from different sensory receptors of sensory neurons in the peripheral nervous system (PNS). A motor nerve carries information from the CNS to the PNS. Afferent nerve fibers link the sensory neurons throughout the body, in neural pathway, pathways to the relevant processing circuits in the central nervous system. Afferent nerve fibers are often paired with efferent nerve fibers from the motor neurons (that travel from the CNS to the PNS), in mixed nerves. Stimuli cause nerve impulses in the receptors and alter the potentials, which is known as sensory transduction. Spinal cord entry Afferent nerve fibers leave the sensory neuron from the dorsal root ganglion, dorsal root ganglia of the spinal cor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Bell
Sir Charles Bell (12 November 177428 April 1842) was a Scottish surgeon, anatomist, physiologist, neurologist, artist, and philosophical theologian. He is noted for discovering the difference between sensory nerves and motor nerves in the spinal cord. He is also noted for describing Bell's palsy. His three older brothers included Robert Bell (1757–1816) a Writer to the Signet, John Bell (1763–1820), also a noted surgeon and writer; and the advocate George Joseph Bell (1770–1843) who became a professor of law at the University of Edinburgh and a principal clerk at the Court of Session. Early life and education Charles Bell was born in Edinburgh on 12 November 1774, as the fourth son of the Reverend William Bell, a clergyman of the Episcopal Church of Scotland. Charles's father died in 1779 when he was five years old, and so his mother had a unique influence on his early life, teaching him how to read and write. In addition to this, his mother also helped Charles' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siméon Denis Poisson
Baron Siméon Denis Poisson (, ; ; 21 June 1781 – 25 April 1840) was a French mathematician and physicist who worked on statistics, complex analysis, partial differential equations, the calculus of variations, analytical mechanics, electricity and magnetism, thermodynamics, elasticity, and fluid mechanics. Moreover, he predicted the Arago spot in his attempt to disprove the wave theory of Augustin-Jean Fresnel. Biography Poisson was born in Pithiviers, now in Loiret, France, the son of Siméon Poisson, an officer in the French Army. In 1798, he entered the École Polytechnique, in Paris, as first in his year, and immediately began to attract the notice of the professors of the school, who left him free to make his own decisions as to what he would study. In his final year of study, less than two years after his entry, he published two memoirs: one on Étienne Bézout's method of elimination, the other on the number of integrals of a finite difference equation. This was so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Complex Number
In mathematics, a complex number is an element of a number system that extends the real numbers with a specific element denoted , called the imaginary unit and satisfying the equation i^= -1; every complex number can be expressed in the form a + bi, where and are real numbers. Because no real number satisfies the above equation, was called an imaginary number by René Descartes. For the complex number is called the , and is called the . The set of complex numbers is denoted by either of the symbols \mathbb C or . Despite the historical nomenclature, "imaginary" complex numbers have a mathematical existence as firm as that of the real numbers, and they are fundamental tools in the scientific description of the natural world. Complex numbers allow solutions to all polynomial equations, even those that have no solutions in real numbers. More precisely, the fundamental theorem of algebra asserts that every non-constant polynomial equation with real or complex coefficie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Friedrich Gauss
Johann Carl Friedrich Gauss (; ; ; 30 April 177723 February 1855) was a German mathematician, astronomer, geodesist, and physicist, who contributed to many fields in mathematics and science. He was director of the Göttingen Observatory and professor of astronomy from 1807 until his death in 1855. While studying at the University of Göttingen, he propounded several mathematical theorems. As an independent scholar, he wrote the masterpieces '' Disquisitiones Arithmeticae'' and ''Theoria motus corporum coelestium''. Gauss produced the second and third complete proofs of the fundamental theorem of algebra. In number theory, he made numerous contributions, such as the composition law, the law of quadratic reciprocity and the Fermat polygonal number theorem. He also contributed to the theory of binary and ternary quadratic forms, the construction of the heptadecagon, and the theory of hypergeometric series. Due to Gauss' extensive and fundamental contributions to science ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sabrina Island (Azores)
Sabrina Island () was an islet formed during the months of June and July 1811 by a submarine volcanic eruption off the coast of Ponta da Ferraria, São Miguel Island, Azores The Azores ( , , ; , ), officially the Autonomous Region of the Azores (), is one of the two autonomous regions of Portugal (along with Madeira). It is an archipelago composed of nine volcanic islands in the Macaronesia region of the North Atl .... The first person to land on the island was Commander James Tillard, captain of the British warship , who hoisted the Union Jack on the island and claimed sovereignty for Kingdom of Great Britain, Great Britain. A diplomatic row with Portugal over the issue ensued, which the island's sinking back into the sea rendered moot. History Formation and discovery Between January and February 1811 a prolonged period of seismic activity affected the settlements to the extreme southwest of São Miguel, in particular in the parishes of Ginetes and Mosteiros (Ponta Delgad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sloop-of-war
During the 18th and 19th centuries, a sloop-of-war was a warship of the Royal Navy with a single gun deck that carried up to 18 guns. The rating system of the Royal Navy covered all vessels with 20 or more guns; thus, the term encompassed all unrated warships, including List of gun-brigs of the Royal Navy, gun-brigs and Cutter (boat), cutters. In technical terms, even the more specialised bomb vessels and fire ships were classed by the Royal Navy as sloops-of-war, and in practice these were employed in the role of a sloop-of-war when not carrying out their specialised functions. In World War I and World War II, the Royal Navy reused the term "sloop" for specialised convoy-defence vessels, including the of the First World War and the highly successful of the Second World War, with anti-aircraft and anti-submarine capabilities. They performed similar duties to the destroyer escorts of the United States Navy, and also performed similar duties to the smaller corvettes of the Royal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
