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Internal displacement in Peru
Internal displacement in Peru is the forced movement of people within the country, caused mainly by the 1980–2000 armed conflict between the state and Shining Path.
Internal drainage board
An internal drainage board (IDB) is an independent local public body in England that manages water levels and reduces flood risk in low-lying areas called internal drainage districts.
Internal energy
Internal energy, also called thermodynamic energy, is the total energy a thermodynamic system contains through its molecules' motion and interactions, excluding the system's overall motion or position.
Internal factions of the Democratic Socialists of America
The internal factions of the Democratic Socialists of America are its organized caucuses, voluntary groupings that run slates for the National Political Committee at biennial national conventions.
Internal Family Systems Model
Internal Family Systems (IFS) is a psychotherapy model by Richard C. Schwartz, from the mid-1980s, treating the mind as parts (exiles, managers, firefighters) led by a core Self; evidence is promising but limited, mainly pilot trials for depression, PTSD, and chronic pain.
Internal fertilization
Internal fertilization: fusion of sperm and egg inside the female's body, dominant in terrestrial animals and plants. Distinguished from external fertilization by copulatory organs, sperm storage, higher multiple paternity in fishes, and deep placoderm fossil origins.
Internal fixation
Internal fracture fixation, combined with surgical realignment as open reduction and internal fixation (ORIF), holds broken bones together with implanted screws, plates, wires, or rods inside the body.
Internal Fixators
Internal fixators are implants, including plates, screws, nails, rods, wires, and pins, placed inside the body to hold fractures in alignment during healing; used in ORIF surgery, historically from Hansmann, Lane, and Lambotte, with steel and titanium as main materials.
Internal gear
An internal gear, also called a ring gear or annulus, is a gear with teeth cut on the inside of a ring, meshing with a pinion inside it.
Internal iliac artery
Internal iliac artery (hypogastric artery), terminal branch of the common iliac artery supplying the pelvis; divides into anterior and posterior trunks, mean length 39.95 mm, diameter 6.86 mm, with Adachi Type I branching in about 56% of people.
Internal jugular vein
Internal jugular vein (vena jugularis interna): paired carotid-sheath vein draining skull, brain, face, and neck to the brachiocephalic vein; JVP window and central access site with higher infection but fewer malpositions than subclavian.
Internal labor market
An internal labor market is a firm or plant where wages and job allocation are governed by administrative rules, with workers hired into entry jobs and promoted from within.
Internal limiting membrane flap technique
The internal limiting membrane flap technique is a vitreoretinal surgical maneuver in which an ILM remnant is inverted over a macular hole to promote its closure.
Internal Macedonian Revolutionary Organization (Вътрешна македонска революционна организация)
Internal Macedonian Revolutionary Organization (VMRO/IMRO), secret revolutionary society founded 1893 in Ottoman Thessaloniki for autonomy of Macedonia and Adrianople; organized the 1903 Ilinden Uprising, split into left and right wings, refounded 1919, banned 1934; distinct from modern successor parties VMRO-DPMNE and VMRO-BNM.
Internal Mammary-Coronary Artery Anastomosis
Internal mammary-coronary artery anastomosis, also called internal thoracic artery grafting, is the original form of coronary artery bypass surgery, first performed clinically by Kolesov in 1964; the LIMA-to-LAD graft is now the standard CABG conduit.
Internal medicine
Internal medicine: the adult-medicine specialty practiced by internists, covering diagnosis and care across all organ systems; three-year US residency, ABIM certification since 1936, subspecialties, hospitalists, and European five-year training.
Internal Medicine Park Won Jang (내과 박원장)
Internal Medicine Park Won Jang (내과 박원장, Dr. Park's Clinic) is a South Korean webtoon by physician-turned-cartoonist Jang Bong-su and its 2022 TVING medical comedy adaptation, 12 episodes starring Lee Seo-jin, about a struggling new clinic owner.
Internal migration
Internal migration is the movement of people across administrative boundaries within a country, without crossing an international border; about 750 million people had done so by the mid-2000s.
Internal migration in Peru
Internal migration in Peru is the movement of Peruvians between the country's regions, above all the twentieth-century exodus from the Andean highlands to the coast, especially Lima.
Internal model control
Internal model control (IMC) is a control system design method in which the controller is built around an explicit model of the controlled process, formalized in 1982.
Internal ophthalmoplegia
Internal ophthalmoplegia (ICD-11 9D01.0) is paralysis of the iris sphincter and ciliary muscle causing mydriasis and lost accommodation from parasympathetic disruption; distinct from internuclear ophthalmoplegia, a brainstem gaze disorder.
Internal passport
Internal passport: a state-issued identity document controlling movement, residence, and services within a country, unlike the external passport; the Soviet 1932 system with propiska registration is the defining historical example.
Internal Passport System of 1932
The Internal Passport System of 1932 (Паспортная система 1932 года) required Soviet citizens aged 16 and over in cities to hold passports with compulsory police registration, the propiska.
Internal phosphorus loading
Internal phosphorus loading is the release of phosphorus from a lake's own sediments into the water, distinct from external loading, and often the main summer phosphorus load in eutrophic lakes.
Internal quantum efficiency
Internal quantum efficiency (IQE) is the ratio of useful internal events in a device, such as photons emitted by an LED, to photons absorbed or carriers injected.
Internal rate of return
The internal rate of return (IRR) is the discount rate that makes the net present value of a series of cash flows equal to zero, found by solving for the rate.
Internal resistance
Internal resistance is the resistance to current flow within a voltage source such as a battery or cell, causing terminal voltage to fall below the emf when current is drawn.
Internal resistance to apartheid
Internal resistance to apartheid: South African opposition inside the country, from the 1960 banning of the ANC and PAC, through Black Consciousness (SASO 1969), the 1976 Soweto Uprising, black trade unions, and the UDF (1983), to the states of emergency of 1985-1986.
Internal resonance
Internal resonance, also called autoparametric resonance, is a nonlinear vibration phenomenon in which modes with commensurate integer frequency ratios exchange energy, producing amplitude saturation and used in MEMS frequency stabilization.
Internal Revenue Code
The Internal Revenue Code (IRC), Title 26 of the U.S. Code, is U.S. federal statutory tax law, current version the 1986 Code as amended after the 1939 and 1954 Codes, administered by Treasury and the IRS.