title: LaGuardia Airport

text: In April 1929, New York Air Terminals, Inc., announced plans to open a private seaplane base at North Beach later that summer. The facility was christened on June 15 and initially featured a concrete plateau connected to the water by a amphibious aircraft ramp, with the former resort converted to a passenger terminal. Opening-day festivities for the new airport were attended by a crowd of 5,000, and included Air Races with Curtiss Seagulls and Sikorsky flying boats, a dedication address by Borough President George U. Harvey, and the commencement of airline service to Albany and Atlantic City by Coastal Airways and Curtiss Flying Service. One month later, service to Boston was launched using Savoia-Marchetti S.55 aircraft operated by Airvia.


title: LaGuardia Airport

text: By 1930, the airport had been improved with hangars and night-illuminated runways, and it housed seaplanes of the recently reorganized New York City Police Department Aviation Unit. On September 23, the site was renamed Glenn H. Curtiss Airport in honor of the New York aviation pioneer who had died one month earlier (not to be confused with the preexisting Curtiss Field in nearby Garden City, nor a similarly renamed airport in Valley Stream). In a ceremony that same day, representatives from the forerunner to Trans World Airlines announced their bid to establish the nation's first transcontinental airmail route to the airport using Ford Trimotors; in attendance were Eleanor Roosevelt and Charles Lindbergh.


title: LaGuardia Airport

text: On August 27, 1931, the airport welcomed the arrival of the world's then-largest airplane, the Dornier Do X, after a 10-month transatlantic journey. Over 18,000 people visited the huge flying boat on its first day of static display, and it remained in the city for nine months. While the Do X was ultimately a commercial failure, its presence demonstrated the viability of long-distance air travel terminating a mere 20-minute drive from Manhattan. Likewise, this centralized location also enabled the airport to host hourly air taxi services between Newark and Brooklyn's Floyd Bennett Field that September.


title: LaGuardia Airport

text: While Curtiss Field was quickly becoming a magnet of aviation, Newark Airport remained the primary terminal for New York City-bound passengers and mail. The city's lack of its own central airport lingered as the 1930s wore on—especially as discussion grew regarding the commercial viability of privately operated fields.


title: LaGuardia Airport

text: The 1934 election of mayor Fiorello La Guardia ushered in a new era of public investment in New York City's airports. Mayor LaGuardia had been a long-time aviation advocate; in a 1927 editorial penned while serving as a US Representative of New York, he criticized both the federal and state governments' slow progress in establishing municipal airports in the city. Although several potential sites had been identified, LaGuardia mainly pushed for the transformation of Governors Island into a combined airport and seaplane base. "No greater monument to the life and activity of the Republic can be imagined," he wrote, painting it as a teeming transportation hub at the extreme center of the city. Military and shipping concerns eventually shut down the proposal, but LaGuardia and industry leaders maintained consensus that New York City needed a central "express" airport to complement the farther-flung Floyd Bennett Field, which it completed in 1930.


title: LaGuardia Airport

text: While the Governors Island proposal was being litigated, LaGuardia also saw development potential in Curtiss Airport. Under his administration, the City entered a 5-year contract with its owners, agreeing to lease the field for $1 per year, with an option to purchase the property for $1,500,000 (). The airport was officially dedicated Municipal Airport 2 on January 5, 1935. At a key ceremony that day, LaGuardia also received a signed lease from TWA for hangar space at Floyd Bennett Field—making it the first major US airline to serve New York City directly. While it would still be years before TWA arrived at North Beach, LaGuardia had begun fulfilling one of his ultimate goals: extracting New York City from "the humiliating position of seeing all its passengers and mail traffic go to a nearby state."


title: LaGuardia Airport

text: The initiative to develop the airport for commercial flights began with an outburst by New York mayor Fiorello La Guardia (in office from 1934 to 1945) upon the arrival of his TWA flight at Newark Airport – the only commercial airport serving the New York City region at the time – as his ticket said "New York". He demanded to be taken to New York, and ordered the plane to be flown to Brooklyn's Floyd Bennett Field, giving an impromptu press conference to reporters along the way. He urged New Yorkers to support a new airport within their city.


title: LaGuardia Airport

text: American Airlines accepted LaGuardia's offer to start a trial program of scheduled flights to Floyd Bennett, although the program failed after several months because Newark's airport was closer to Manhattan. La Guardia went as far as to offer police escorts to airport limousines in an attempt to get American Airlines to continue operating the trial program.


title: LaGuardia Airport

text: During the Floyd Bennett experiment, LaGuardia and American executives began an alternative plan to build a new airport in Queens, where it could take advantage of the new Queens–Midtown Tunnel to Manhattan. The existing North Beach Airport was an obvious location, but much too small for the sort of airport that was being planned. With backing and assistance from the Works Progress Administration, construction began in 1937, it is on the waterfront of Flushing and Bowery Bays in East Elmhurst and borders the neighborhoods of Astoria and Jackson Heights. Building on the site required moving landfill from Rikers Island, then a garbage dump, onto a metal reinforcing framework. The framework below the airport still causes magnetic interference on the compasses of outgoing aircraft: signs on the airfield warn pilots about the problem.


title: LaGuardia Airport

text: Because of American's pivotal role in the development of the airport, LaGuardia gave the airline extra real estate during the airport's first year of operation, including four hangars, which was an unprecedented amount of space at the time. American opened its first Admirals Club (and the first private airline club in the world) at the airport in 1939. The club took over a large office space that had previously been reserved for the mayor, but he offered it for lease following criticism from the press, and American vice president Red Mosier immediately accepted the offer.


title: LaGuardia Airport

text: The airport was dedicated on October 15, 1939, as the New York Municipal Airport, and opened for business on December 2 of that year. It cost New York City $23 million to turn the tiny North Beach Airport into a modern facility. Not everyone was as enthusiastic as La Guardia about the project; some critics regarded it as a $40 million boondoggle. But the public was fascinated by the very idea of air travel, and thousands traveled to the airport, paid the dime fee, and watched the airliners take off and land. Two years later these fees and their associated parking had already provided $285,000, and other non-travel related incomes (food, etc.) were another $650,000 a year. The airport was soon a financial success. A smaller airport in nearby Jackson Heights, Holmes Airport, was unable to prevent the expansion of the larger airport and closed in 1940.


title: LaGuardia Airport

text: Newark Airport began renovations, but could not keep up with the new Queens airport, which "TIME" called "the most pretentious land and seaplane base in the world". Even before the project was completed LaGuardia had won commitments from the five largest airlines (Pan American Airways, American, United, Eastern Air Lines and Transcontinental and Western Air) to begin using the new field as soon as it opened. Pan Am's transatlantic Boeing 314 flying boats moved to La Guardia from Port Washington in 1940. During World War II the airport was used to train aviation technicians and as a logistics field. Transatlantic landplane airline flights started in late 1945; some continued after Idlewild (now John F. Kennedy International) opened in July 1948, but the last ones shifted to Idlewild in April 1951.


title: LaGuardia Airport

text: Newspaper accounts alternately referred to the airfield as New York Municipal Airport and LaGuardia Field until the modern name was officially applied when the airport moved to Port of New York Authority control under a lease with New York City on June 1, 1947.


title: LaGuardia Airport

text: LaGuardia opened with four runways at 45-degree angles to each other, the longest (13/31) being . Runway 18/36 was closed soon after a United DC-4 ran off the south end in 1947; runway 9/27 (4,500 ft) was closed around 1958, allowing LaGuardia's terminal to expand northward after 1960. Circa 1961 runway 13/31 was shifted northeastward to allow construction of a parallel taxiway (such amenities being unknown when LGA was built) and in 1965–66 both remaining runways were extended to their present .


title: LaGuardia Airport

text: The April 1957 Official Airline Guide shows 283 weekday fixed-wing departures from LaGuardia: 126 American, 49 Eastern, 33 Northeast, 31 TWA, 29 Capital and 15 United. American's flights included 26 nonstops to Boston and 27 to Washington National (mostly Convair 240s). Jet flights (United 727s to Cleveland and Chicago) started on June 1, 1964.


title: LaGuardia Airport

text: Although LaGuardia was a large airport for the era in which it was built, it soon became too small. Starting in 1968 general aviation aircraft were charged heavy fees to operate from LaGuardia during peak hours, driving many LGA operators to airports such as Teterboro Airport in Teterboro, New Jersey. The increase in traffic at LaGuardia and safety concerns prompted the closure of nearby Flushing Airport in 1984. Also in 1984, to further combat overcrowding at LGA, the Port Authority instituted a Sunday-thru-Friday "perimeter rule" banning nonstop flights from LaGuardia to cities more than away; at the time, Denver was the only such city with nonstop flights, and it became the only exception to the rule. (In 1986 Western Airlines hoped to fly 737-300s nonstop to Salt Lake City and unsuccessfully challenged the rule in federal court.) Later, the Port Authority also moved to connect JFK and Newark Airport to regional rail networks with the AirTrain Newark and AirTrain JFK, in an attempt to make these more distant airports competitive with LaGuardia. In addition to these local regulations, the FAA also limited the number of flights and types of aircraft that could operate at LaGuardia.


title: LaGuardia Airport

text: LaGuardia's traffic continued to grow. By 2000, the airport routinely experienced overcrowding delays, many more than an hour long. That year, Congress passed legislation to revoke the federal traffic limits on LaGuardia by 2007. The reduced demand for air travel following the September 11, 2001, terrorist attacks on New York City quickly slowed LaGuardia's traffic growth, helping to mitigate the airport's delays. Ongoing Port Authority investments to renovate the Central Terminal Building and improve the airfield layout have also made the airport's operations more efficient in recent years.


title: LaGuardia Airport

text: FAA approved Instrument Departure Procedure "Whitestone Climb" and the "Expressway Visual Approach to Runway 31". When adopting the Expressway Approach, when the aircraft crosses the intersection of I-278 and the Long Island Expressway in Long Island City, it turns northeast on 85° and follows the Long Island Expressway, after reaching Flushing Meadow Park, the aircraft executes a 135° left turn over the Flushing Bay and joins the final approach to the Runway 31. When adopting Whitestone Climb, aircraft will circle over Flushing and head to Whitestone Bridge on the North upon takeoff from Runway 13. Such patterns aim to reduce the noise, avoid the traffic of the JFK Airport and maximize the air traffic capacity in the New York TRACON.


title: LaGuardia Airport

text: In late 2006, construction began to replace the Wallace Harrison designed air traffic control tower built in 1962 with a more modern one. The tower began operations on October 9, 2010.


title: LaGuardia Airport

text: On August 12, 2009, Delta Air Lines and US Airways announced a landing slot and terminal swap in separate press releases. Under the swap plan, US Airways would have given Delta 125 operating slot pairs at LaGuardia. US Airways, in return, would have received 42 operating slot pairs at Ronald Reagan National Airport in Washington, D.C., and be granted the authority to begin service from the US to São Paulo, Brazil, and Tokyo, Japan. When the swap plan was complete, Delta Shuttle operations would have moved from the Marine Air Terminal to Terminal C (the present US Airways terminal), and Terminals C and D would have been connected together. US Airways Shuttle flights would have moved to the Marine Air Terminal, and mainline US Airways flights would have moved to Terminal D (the present Delta terminal).


title: LaGuardia Airport

text: The United States Department of Transportation announced that they would approve the Delta/US Airways transaction under the condition that they sell slots to other airlines. Delta and US Airways dropped the slot swap deal in early July 2010 and both airlines filed a court appeal. In May 2011, both airlines announced that they would resubmit their proposal of the slot swap to the US DOT. It was tentatively approved by the US DOT on July 21, 2011. The slot swap received final approval from the US DOT on October 10, 2011.


title: LaGuardia Airport

text: On December 16, 2011, Delta Air Lines announced plans to open a new domestic hub at LaGuardia Airport. The investment was the largest single expansion by any carrier at LaGuardia in decades, with flights increasing by more than 60 percent, and destinations by more than 75 percent. By summer 2013, Delta increased operations to 264 daily flights between LaGuardia and more than 60 cities, more than any other airline at LaGuardia.


title: LaGuardia Airport

text: In November 2019, Southwest Airlines ended service to Newark primarily due to the Boeing 737 MAX groundings, poor performance, and inadequate facilities, and consolidated its New York-area operations to LaGuardia and Islip.


title: LaGuardia Airport

text: In April 2010, Port Authority director Christopher Ward announced that the agency had hired consultants to explore a full demolition and rebuilding of LaGuardia's Central Terminal. The project would create a unified, modern, and efficient plan for the airport, currently an amalgam of decades of additions and modifications. The project, expected to cost $2.4 billion, will include the demolition of the existing central terminal building and its four concourses, garage, Hangar 1, and frontage roads; building temporary facilities, and designing and building a new central terminal building. The rebuilding would be staged in phases in order to maintain operations throughout the project.


title: LaGuardia Airport

text: Proposals were due on January 31, 2012. Patrick Foye, executive director of the Port Authority, said, "It's got a quaint, nostalgic but unacceptable kind of the 1940s, 1950s feel that's just not acceptable." The Port Authority was seeking a private company to develop and operate the replacement terminal with private funds, similar to how Delta operates the other terminals at the airport. However, in January 2014, Governor Andrew Cuomo announced a plan for the state to oversee the construction of the long-stalled new terminal project instead of the proposed public-private partnership.


title: LaGuardia Airport

text: On July 27, 2015, Governor Andrew Cuomo, joined by then-Vice President Joe Biden, announced a $4 billion plan to rebuild the terminals as one contiguous building with terminal bridges connecting buildings. Airport officials and planners had concluded that the airport essentially had to be torn down and rebuilt.


title: LaGuardia Airport

text: Under the airport reconstruction plan disclosed in 2015, a single terminal building is to be constructed in stages, with a people mover, retail space and a new hotel. Some of additional taxiways are to be built. A people mover is to connect the new terminal sections, the Grand Central Parkway is to be reconfigured, and AirTrain LaGuardia, previously announced, will connect the airport to the Mets–Willets Point subway station and the Mets–Willets Point LIRR station. A proposed high-speed ferry, if introduced, will service the Marine Air Terminal, a national historic landmark, which will remain intact. An onsite tram has also been proposed to move passengers more quickly within the central terminal. The new airport is to be eco-friendly and contain accommodations such as a hotel of approximately 200 rooms and a business/conference center. The entire airport will move closer to the Grand Central Parkway. New parking garages replaced parking facilities between the existing terminals and Grand Central Parkway, creating space for the new facilities. By locating the terminals closer to the Grand Central Parkway, additional space for aircraft taxiways and hold areas was created, reducing ground delays. The runways themselves were not reconfigured.


title: LaGuardia Airport

text: Construction of the project's first phase started in spring of 2016, once final plans were approved by the Port Authority board, with the entire redevelopment scheduled to be completed by late 2022. Terminal B will be demolished, and Delta will rebuild its terminals C and D in coordination with the plan. The new airport will feature an island gate system, with passengers connecting between the terminal building and the gates via bridges that will be high enough for aircraft to taxi under. In late March 2016, the comprehensive plans for the redevelopment were approved unanimously between the Port Authority of New York, New Jersey, and LaGuardia Gateway Partners for the Terminal B Project. Construction costs were estimated to range from $4 billion to $5.3 billion. In August 2017, Magic Johnson Enterprises and Loop Capital created a joint venture named JLC Capital to invest in Phase 2 of LaGuardia Airport's reconstruction. The same month, Delta broke ground on the last phase of the airport's reconstruction. On December 9, 2017, six airlines moved at LGA in anticipation of the new terminals. Alaska Airlines and JetBlue moved to the Marine Air Terminal. American consolidated in Terminal B. Frontier and Spirit depart from Terminal C and arrive at Terminal D. Since the move, there have been further changes with Alaska Airlines ending service to LaGuardia, JetBlue moving all but Boston flights to Terminal B, and Spirit consolidating its operations in Terminal A.


title: LaGuardia Airport

text: LaGuardia Gateway Partners, which manages the construction of Terminal B, has completed most of the complex. The first half of the seven-level West Parking Garage opened in February 2018, with 1,600 of 3,100 parking spaces being made available, and the rest of the garage was opened later that year. Eleven new gates at Terminal B opened on December 1, 2018, and were used by Air Canada, American Airlines, and Southwest Airlines. Five additional gates opened on June 2, 2019, when United relocated most of its operations to the new concourse. The new space included a concourse with a ceiling, food concessions, an FAO Schwarz toy store, and an indoor play area. The new headhouse at Terminal B opened on June 13, 2020, along with the new connector to the Eastern Concourse. On August 5, 2020, American opened the first seven gates of the Western Concourse, with ten additional gates and the bridge connector scheduled to open at the end of 2021. The second bridge connecting to Terminal B was later completed and opened to the public on January 27, 2022.


title: LaGuardia Airport

text: On the east side of the airport, Delta is consolidating its two terminals, Terminal C and D, into a centralized Terminal C headhouse, which is located on the former Terminal D parking site. In addition, Delta is rebuilding its airside facilities into four "finger" concourses. The first concourse to open was Concourse G on the eastern end of the airport, which opened on October 29, 2019. Delta Shuttle flights moved to the Concourse G on November 16, 2019. On June 4, 2022, Delta unveiled its new Terminal C headhouse to the public in tandem with concourse E, which boasts 10 narrow body gates. The Terminal C headhouse consolidates the former Terminal C and D's security checkpoint into 11 lanes which, if necessary, can be expanded to 16 lanes. Other features include a dedicated drop-off area for carry-on-only passengers, biometric scanning technology, a sensory room designed for those with autism, and Delta's largest Sky Club to date.


title: LaGuardia Airport

text: As of June 2022, Delta is in the process of replacing Terminal D's gates and will start construction of Concourse D. Delta is fast-tracking its remaining projects at Terminal C due to the impacts from the COVID-19 pandemic, which allowed the airline to use the decrease in passage traffic to speed up construction by two years.


title: LaGuardia Airport

text: While LaGuardia frequently accommodates general aviation, the airport is primarily serviced by Part 121 scheduled air carriers providing passenger service to regional, domestic, and limited international destinations. Because of its congested nature and proximity to dense urban neighborhoods, commercial flights to and from the airport are subject to several restrictions enacted by both the Federal Aviation Administration (FAA) and the Port Authority of New York and New Jersey (PANYNJ). The airport almost only ever handles narrow-body aircraft and can handle Airplane Design Group (ADG) IV widebody aircraft such as the Boeing 767 and the Airbus A310, however these aircraft in this group are rarely seen at LaGuardia.


title: LaGuardia Airport

text: The airport does not have U.S. Customs and Border Protection (CBP) facilities. As such, international arrivals are only possible from airports serviced by United States border preclearance. Passengers and crewmembers on these flights clear customs at their departure airport and—for immigration purposes—are considered to be on the US territory during their entire journey, allowing them to exit LaGuardia in the same manner as domestic travelers.


title: LaGuardia Airport

text: To mitigate the impact of aircraft noise pollution and facilitate airfield maintenance, a seasonal curfew traditionally exists between the hours of 12am and 6am during the warm months of the year. Additionally, a 1984 "Perimeter Rule" implemented by PANYNJ bars airline flights to and from points farther than , except on Saturdays or to Denver, Colorado. With long haul operations generally requiring heavier fuel loads and larger aircraft, the regulation aims to eliminate excess perceived noise generated by such flights. Changes to the Perimeter Rule were considered as recently as 2015, but a New York State Senate bill was introduced in 2021 with the intent of codifying the rule into law.


title: LaGuardia Airport

text: As one of the United States' most-dense and congested Class B airports, LaGuardia's IFR operations are governed by an FAA slot system. Operators are granted time-sensitive individual takeoff and landing rights in accordance with the International Air Transport Association's Worldwide Airport Slot Guidelines (WASG)"." In 2020, the FAA responded to drastic reductions in air traffic caused by the COVID-19 pandemic by suspending the expiration of unused slots at several US airports including LaGuardia.


title: LaGuardia Airport

text: LaGuardia has three active terminals (A, B, and C) with 72 gates. The terminals are all connected by buses and walkways. Signage throughout the terminals was designed by Paul Mijksenaar. As with the other Port Authority airports, some terminals at LaGuardia are managed and maintained by airlines themselves. Terminal B was under direct Port Authority operation; however, in 2016, operation of Terminal B was transferred to a private company, LaGuardia Gateway Partners.


title: LaGuardia Airport

text: LaGuardia is undergoing a multi-billion dollar redesign that resulted in a new Terminal B and a new Terminal C (encompassing the old Terminals C and D). Terminal A remains unchanged except for minor updates. The new layout will consist of new gate concourses as well. The new Terminal B has two gate concourses referred to as the Western Concourse (Gates 11–31) and Eastern Concourse (Gates 40–59). The new Terminal C has four gate concourses (numbered 61–69, 71–79, 82–89, and 92–98).


title: LaGuardia Airport

text: Terminal A, known as the Marine Air Terminal (MAT), was the airport's original terminal for overseas flights. The waterfront terminal was designed to serve the fleet of flying boats, or Clippers, of Pan American Airways, America's main international airline throughout the 1930s and 1940s. When a Clipper landed in Long Island Sound, it taxied to a dock where passengers could disembark into the terminal. During World War II, new four-engine land planes were developed, and flying boats stopped carrying scheduled passengers out of New York after 1947. The last Pan American flight left the terminal in February 1952, bound for Bermuda.


title: LaGuardia Airport

text: Inside the terminal hangs "Flight", a mural measuring in height and in length; it was the largest mural created as part of the Great Depression–era Works Progress Administration (WPA). Completed by James Brooks in 1942, "Flight" depicts the history of humanity's involvement with flight. The mural was painted over without explanation by the Port Authority of New York and New Jersey in the 1950s, possibly because some saw left-wing symbolism in it. After an extensive restoration project headed by aviation historian Geoffrey Arend, the mural was rededicated in 1980.


title: LaGuardia Airport

text: In 1986, Pan Am restarted flights at the MAT with the purchase of New York Air's shuttle service between Boston, New York City, and Washington, D.C. In 1991, Delta Air Lines bought the Pan Am Shuttle and subsequently started service from the MAT on September 1. In 1995, the MAT was designated as a historic landmark. A $7 million restoration was completed in time for the airport's 65th anniversary of commercial flights on December 2, 2004. On December 9, 2017, JetBlue and Alaska Airlines relocated to the MAT, while Delta consolidated all Delta Shuttle flights to Terminal C. On October 27, 2018, Alaska Airlines ended all service from LaGuardia Airport, leaving JetBlue as the terminal's only tenant. On April 28, 2021, Spirit Airlines started operating its Fort Lauderdale-bound flights from Terminal A. On July 20, 2021, JetBlue announced that they will be relocating from the MAT to Terminal B, a move they completed on July 9, 2022, with the relocation of Boston flights to Terminal B. On March 29, 2022, all flights operated by Spirit Airlines now operate out of the MAT. On September 13 of that year, Frontier Airlines moved all of its flights to Terminal A.


title: LaGuardia Airport

text: Terminal B serves many airlines, and it functions as a large hub for American Airlines. In 2017, work started on the first of two new concourses, which replaced the old A, B, C, and D concourses. The new terminal was designed by Hellmuth, Obata + Kassabaum.


title: LaGuardia Airport

text: In 2020, the new Terminal B headhouse opened with a bridge connecting it to the completed Eastern Concourse. On January 27, 2022, a second bridge was completed, connecting Terminal B's headhouse to the Western Concourse. In 2022, the old Terminal B was demolished.


title: LaGuardia Airport

text: On October 31, 2021, JetBlue moved to Terminal B (except for flights to Boston), as the airline wanted to make connections easier with American Airlines due to the "Northeast Alliance" between them. JetBlue's Boston flights moved to Terminal B on July 9, 2022.


title: LaGuardia Airport

text: In 2020, 8 gates at Terminal B's new Western Concourse opened (24–31). An additional 4 gates (19, 20, 22, and 23) were opened on December 15, 2021, along with a new American Airlines Admirals Lounge. With the opening of these new gates, the old concourse D, the last of the old Terminal B gates, was closed to traffic. An additional 2 gates (17 and 18) were opened on April 18, 2022. Another gate, Gate 11, came online as of May 17, 2022, and on June 8, 2022, two more gates, Gate 12 and Gate 14, were opened. On July 9, 2022, the final two new gates, Gate 15 and Gate 16, opened. However, Gate 23 has been taken out of service to move its jetway to the new Gate 16. American Airlines now operates all flights in this concourse.


title: LaGuardia Airport

text: On December 1, 2018, eleven gates at Terminal B's new Eastern Concourse opened. Five additional gates opened on June 2, 2019, allowing United Airlines to move all of its operations at LaGuardia to the new concourse. On May 20, 2022, the jetway from Gate 49 was moved to Western Concourse Gate 14 for installation.


title: LaGuardia Airport

text: The new Terminal C, designed by Corgan, opened on June 4, 2022, and connects to four concourses serving Delta Air Lines and WestJet (D, E, F, and G). Two of these concourses are new (E and G) and two (D and F) are part of the original Terminal C and D and will be used while new concourses are completed. While the old Terminal C and Terminal D buildings remain while its concourses are still active, the ticketing and baggage operations of these gates have been consolidated into the new Terminal C. When completed, the new Terminal C will include access to 37 gates in its four concourses. The new Terminal C also has a Delta Sky Club, the airline's largest.


title: LaGuardia Airport

text: The Central Terminal Building was originally six blocks long, and consisted of a four-story central section, two three-story wings, and four concourses (A, B, C, and D) with 40 aircraft gates. The $36 million facilities designed by Harrison and Abramovitz was dedicated on April 17, 1964. Delta and US Airways left the CTB in 1983 and 1992 respectively for their own dedicated terminals on the east side of the airport. The Port Authority and various airlines carried out a $340 million improvement project in the 1990s to expand and renovate the existing space. The terminal was replaced by the new Terminal B, with the final gates (Concourse D) and terminal already demolished in early 2022.


title: LaGuardia Airport

text: Terminal C (formerly known as the East End Terminal and USAir Terminal) was a facility that opened September 12, 1992, at a cost of $250 million. Designed by William Nicholas Bodouva + Associates Architects and Planners, it housed part of Delta's operations at LaGuardia. On June 4, 2022, Terminal C's check-in and baggage claim areas were closed.


title: LaGuardia Airport

text: The building was initially conceived in a 1989 agreement between the Port Authority and Texas Air Corporation (then-owner of Continental Airlines and Eastern Air Lines). When Eastern was forcibly bankrupted by Texas Air, its assets—including the new terminal's leases—were transferred to Continental. Continental never moved in, and in turn, sold the leases (along with most of its LaGuardia slots) to US Airways as part of a bankruptcy restructuring. Trump Shuttle, successor to the Eastern Air Shuttle, also occupied the terminal before becoming US Airways Shuttle.


title: LaGuardia Airport

text: As a result of a slot-swap deal between Delta and US Airways, as of July 2012, Delta occupied the majority of the terminal (gates C15–C44). American (the former US Airways flights) operated some flights from gates C35–C44 until December 9, 2017. The eastern concourse connected to Terminal C has been closed and demolished (Gates C15-C24), and the construction of the new Concourse E has been completed. The new concourse opened to the public on June 4, 2022. This new concourse is numbered 70–79 for its gates.


title: LaGuardia Airport

text: Terminal D opened on June 19, 1983, at a cost of approximately $90 million, and was designed by William Nicholas Bodouva + Associates Architects to accommodate Delta's new Boeing 757 and Boeing 767 aircraft. This terminal also housed Northwest Airlines and Northwest Airlink from its opening in 1983 until the merger into Delta in 2009.


title: LaGuardia Airport

text: As of January 8, 2020, Delta Air Lines and Delta Connection operate out of the new Concourse G that was connected to Terminal D. Terminal D was connected to Terminal C by a 600-foot walkway, which opened in early 2013 as part of Delta's effort to build a hub at LaGuardia. As of September 1, 2020, the walkway between Terminals C and D were demolished, and the construction of the new Concourse F is currently underway.


title: LaGuardia Airport

text: As of June 4, 2022, Terminal D's check-in and baggage claim areas were closed. During the week of September 12–18, 2022, the central and eastern sections of Terminal D were demolished. The West end of Terminal D with a Delta Sky Club and gates 81–85 remain standing and are still in use. This section is connected to the new Terminal C via a walkway bridge. The remaining gates will stay in operation until the new Concourse F is complete which will use gate numbers 82–89.


title: LaGuardia Airport

text: Although there is no separate terminal building for general aviation aircraft a pseudo-terminal is operated within the Marine Air Terminal (Terminal A), which is currently run by Sheltair Aviation providing full FBO services to private and charter aircraft owners-pilots including 100LL and Jet A fueling, computerized weather, and flight planning as well as pilot and passenger lounges. To access the General Aviation terminal an on-airport tenant must possess a SIDA (Security Identification Display Area) badge for unescorted access, transient aircraft owners-pilots and passengers must be escorted at all times into and out of the GA Terminal and to the ramp and hangar areas by the FBO staff.


title: LaGuardia Airport

text: Following the events of the terrorist attacks on September 11, 2001, the Federal Aviation Administration changed the rules for the landing and departure of general aviation aircraft at LaGuardia. Pilots operating a non-scheduled IFR flight are now required to make a reservation via the FAA's e-CVRS system no more than 72 hours prior to the flight's arrival or departure while public charter flights may make a reservation up to six months prior. Unscheduled IFR flights may only operate at LaGuardia with a reservation from the hours of 6:00 am to 9:59 pm local time Monday thru Friday and 12:00 pm to 9:59 pm local time on Sundays. Reservations for unscheduled IFR flights are not required all day on Saturdays. Aircraft without a reservation will be redirected to either Teterboro Airport or Linden Airport.


title: LaGuardia Airport

text: A private seaplane base, EDO , operates three waterways in Flushing Bay and the East River north of LaGuardia Airport.


title: LaGuardia Airport

text: , buses are the only mode of mass transit to connect the airport with its surroundings. All terminals are served by accessible public MTA bus lines—including two Select Bus Services (SBS)—and free transfers to the New York City Subway are provided via OMNY or MetroCard payments.


title: LaGuardia Airport

text: The airport also features a complementary internal shuttle bus route which makes stops at all terminals.


title: LaGuardia Airport

text: Despite many failed proposals throughout its history, LaGuardia is not served directly by rail. Nearby lines of the New York City Subway and Long Island Rail Road (LIRR), however, provides northern Queens with connections to the greater New York metropolitan area and are commonly accessed from the airport by public bus or private car services.


title: LaGuardia Airport

text: The airport is mainly accessible via the Grand Central Parkway and overpasses at 94th street and 102nd street. Taxicabs serving LaGuardia are metered and licensed by the New York City Taxi and Limousine Commission, and uniformed airport employees are stationed to dispatch fares. For-hire-vehicles (FHV) including limousines and rideshare operators are accommodated at designated locations. In 2019, PANYNJ approved the implementation of "airport access fee" surcharges on FHV and taxi trips, with the revenue earmarked to support the agency's capital programs.


title: LaGuardia Airport

text: Law enforcement and Aircraft rescue and firefighting (ARFF) services are provided by the Port Authority Police Department (PAPD). The agency's LaGuardia Airport Command (Building 137) was completed in 2010. Emergency medical services are provided by North Shore University Hospital under contract to the Port Authority.


title: LaGuardia Airport

text: Overlooking the approach end of runway 4 is Planeview Park, a public park operated by the New York City Department of Parks and Recreation. The space contains park benches and lawns adjacent the Grand Central Parkway along the southern perimeter of the airport and is a prime viewing location for aircraft spotting.


title: Mehmed VI

text: Mehmed VI Vahideddin ( "Meḥmed-i sâdis" or "Vaḥîdü'd-Dîn"; or /; 14 January 1861 – 16 May 1926), also known as Şahbaba () among the Osmanoğlu family, was the 36th and last Sultan of the Ottoman Empire, reigning from 4 July 1918 until 1 November 1922, when the Ottoman Empire was dissolved after World War I and replaced by the Republic of Turkey on 29 October 1923.


title: Mehmed VI

text: The brother of Mehmed V, he became heir to the throne in 1916, after the suicide of Abdülaziz's son, Şehzade Yusuf Izzeddin, as the eldest male member of the House of Osman. He acceded to the throne after the death of Mehmed V. He was girded with the Sword of Osman on 4 July 1918 as the thirty-sixth "padishah". His father was Sultan Abdulmejid I, and his mother was Gülistu Kadın (1830–1865). She was of Georgian-Abkhazian origin, the daughter of Prince Tahir Bey Chachba, who was originally named Fatma Chachba. After her death, Mehmed was adopted by Şayeste Hanım.


title: Mehmed VI

text: Mehmed stepped down when the Ottoman Sultanate was abolished in 1922 and the secular Republic of Turkey was created, with Mustafa Kemal Atatürk as the first president.


title: Mehmed VI

text: Mehmed VI was born at the Dolmabahçe Palace, in Constantinople, on 14 January 1861. Mehmed's father died when Mehmed was only five months old, and Mehmed's mother died when he was four years old. He was raised and taught by his step-mother Şayeste Hanım. He trained himself by taking lessons from private teachers and attending some of the lessons given at Fatih Madrasa. The prince had a rough time with his overbearing stepmother, and at the age of 16 he left his stepmother's mansion with the three servants who had been serving him since childhood. He grew up with nannies, female servants, and tutors. During the thirty-three years of his brother Sultan Abdul Hamid II's reign he lived in the Ottoman Imperial Harem.


title: Mehmed VI

text: During his youth his closest friend was Abdulmejid II, the son of his uncle, Sultan Abdulaziz. In the years to come, however, the two cousins became unyielding rivals. Before moving to the Feriye Palace, the prince had lived briefly in the mansion in Çengelköy owned by Şehzade Ahmed Kemaleddin.


title: Mehmed VI

text: During the reign of Sultan Abdul Hamid, Mehmed was considered to be the Sultan's closest brother. In the years to come, when he ascended to the throne, this closeness would greatly influence his political attitudes, such as his intense dislike of the Young Turks and the Union and Progress Party, and his sympathy for the British.


title: Mehmed VI

text: Mehmed took private lessons. He read a great deal, and was interested in various subjects, including the arts, which was a tradition of the Ottoman family. He took courses in calligraphy and music and learned how to write in the naskh script and to play the kanun.


title: Mehmed VI

text: Then he became interested in Sufism and, unknown to the Palace, he followed courses at the madrasa of Fatih on Islamic jurisprudence, Islamic theology, interpretation of the Quran, and the Hadiths, as well as in Arabic and Persian. He attended the dervish lodge of Ahmed Ziyaüddin Gümüşhanevi, located not far from the Sublime Porte, where Ömer Ziyaüddin of Dagestan was the spiritual leader, and he became a disciple of the Naqshbandi order.


title: Mehmed VI

text: The First World War was a disaster for the Ottoman Empire. British and allied forces captured Baghdad, Damascus, and Jerusalem during the war, and most of the Ottoman Empire was divided amongst the European allies. At the San Remo conference of April 1920, the French were granted a mandate over Syria and the British were granted one over Palestine and Mesopotamia. On 10 August 1920, Mehmed's representatives signed the Treaty of Sèvres, which recognised the mandates and recognised Hejaz as an independent state.


title: Mehmed VI

text: The Sultan requested the resignation of the Unionist government and assigned Ahmed Tevfik Pasha to form the government. In the speech of the opening of the new legislative year of the parliament, Woodrow Wilson said that he applied for peace according to his principles, that he wanted peace in accordance with the honour and dignity of the state, that he believed that the precious places of the homeland were not occupied, and that the army would begin heroically. Mustafa Kemal Pasha, who sent a telegram to the Sultan, asked the government to establish Ahmed Izzet Pasha and make him a minister of Harbiye.The sultan assigned the task of forming the government to his son Ahmed Izzet Pasha.


title: Mehmed VI

text: The new government, consisting of members of the Liberty and Accord Party, arrested the leaders of the Committee of Union and Progress, including one of the former grand viziers, Said Halim Pasha. The trial of Boğazlıyan District Governor Kemal Bey was quickly concluded, and the death penalty was carried out in Beyazıt Square after the fatwa was signed by the sultan.


title: Mehmed VI

text: Meanwhile, the French General d'Esperey, who came to Istanbul, threatened to go to the palace with a battalion of soldiers and make what he wanted by burning the distractions of the sultan and his government. He called him to the embassy without visiting the Grand Vizier. The French handed over a list of thirty-six people they wanted to arrest to the government.


title: Mehmed VI

text: Turkish nationalists rejected the settlement by the Sultan's four signatories. A new government, the Turkish Grand National Assembly, under the leadership of Mustafa Kemal (Atatürk), was formed on 23 April 1920, in Ankara (then known as Angora). The new government denounced the rule of Mehmed VI and the command of Süleyman Şefik Pasha, who was in charge of the army commissioned to fight against the Turkish National Movement (the Kuvâ-i İnzibâtiyye); as a result, a temporary constitution was drafted.


title: Mehmed VI

text: On 22 July 1920, Şurayı Saltanat was gathered in Yıldız Palace to discuss the principles of the Treaty of Sèvres. The Sèvres Agreement was signed on 10 August 1920. Since he had to resign two and a half-months later, Ferid Pasha founded the last delegation of Tevfik Pasha, the last delegation of the Ottoman Empire, on 2 October 1920.


title: Mehmed VI

text: As the nationalist movement strengthened its military positions in late August 1922, Mehmed VI, his five wives, and attendant eunuchs could no longer leave the safety of the palace. The Grand National Assembly of Turkey abolished the Sultanate on 1 November 1922, and Mehmed VI was expelled from Istanbul. One day before his departure, he had lunch with his daughter, Ulviye Sultan, and spent a night at her palace. Leaving aboard the British warship "Malaya" on 17 November 1922, he took care not to bring valuable items or jewellery, other than his personal belongings. British general Charles Harington himself took the last Ottoman ruler from Yıldız Palace. Ten people with the sultan were sent off early in the morning by an English battalion. He went into exile in Malta, later living on the Italian Riviera.


title: Mehmed VI

text: On 16 November 1922, the Sultan wrote to Sir Charles Harington: "Sir, considering my life in danger in Istanbul, I take refuge with the British Government and request my transfer as soon as possible from Istanbul to another place. Mehmed Vahideddin, Caliph of the Muslims". Accompanied by his First Chamberlain, the bandmaster, his doctor, two confidential secretaries, a valet, a barber and two eunuchs, at 6am on 19 November, two British ambulances took them to the house of General Sir Charles Harington. On 19 November, Mehmed's first cousin and heir, Abdulmejid Efendi, was elected caliph, becoming the new head of the Imperial House of Osman as Abdulmejid II before the Caliphate was abolished by the Turkish Grand National Assembly in 1924.


title: Mehmed VI

text: Mehmed sent a declaration to the Caliphate Congress and protested the preparations made, declaring that he had never waived the right to reign and be caliph. The congress met on 13 May 1926, but Mehmed died without the news of the congress meeting on 16 May 1926 in Sanremo, Italy. His daughter Sabiha Sultan found money for a burial, and the coffin was taken to Syria and buried in the cemetery of the Sulaymaniyya Takiyya in Damascus.


title: Mehmed VI

text: Mehmed had an optimistic and patient personality according to the testimony of his relatives and employees. He was evidently a kind family man in his palace; outside, and especially at official ceremonies, he would stand cold, frowning and serious, and would not compliment anyone; he attached great importance to religious traditions; he would not tolerate rumors, nor would he allow them to circulate in his palace. Even in his informal conversations, he always attracted attention with seriousness. The sources in question also state that he was intelligent and quick-grasped, but he was under the influence of his entourage and especially those he believed in, that he had a very evident, unstable and stubborn temperament.


title: Mehmed VI

text: Mehmed VI had dealt with advanced literature, music, and calligraphy. His compositions were performed in the palace when he was on the throne. The lyrics of the songs he repeatedly composed while in Tâif envision the longing of the country and the pain of not getting the news that they have left behind. Sixty-three works belonging to him can be identified, but only forty works have notes. His poems, which can be an example to his poetry, are only the lyrics of his songs. He was also a good calligrapher.


title: BoA

text: Kwon Bo-ah (; born November 5, 1986), known professionally as BoA, is a South Korean singer, songwriter, dancer, record producer and actress. One of the most successful and influential Korean entertainers, she has been dubbed the "Queen of K-pop."


title: BoA

text: Born and raised in Gyeonggi-do, South Korea, BoA was discovered by SM Entertainment talent agents when she accompanied her older brother, a music video director, to a talent search in 1998. She was trained for two years and made her debut in August 2000. BoA has released twenty studio albums, including ten in Korean, nine in Japanese, and one in English. On television, she appeared as a judge on the reality competition show "K-pop Star" (2011–2013), as an actress on the television drama "Listen to Love" (2016), as a host for the second season of "Produce 101" (2017), and as a coach for the third season of "The Voice of Korea" (2020).


title: BoA

text: BoA's ability to sing in Japanese, English and Mandarin has helped her find commercial success beyond South Korea, in China, Japan, Taiwan, and Singapore. With the release of her debut Japanese studio album, "Listen to My Heart" (2002), BoA became the first South Korean pop star to break through in Japan following the fall of barriers that had restricted the import and export of entertainment between the countries since the end of World War II. She is the only foreign artist with three albums that have sold more than one million copies in Japan and one of only three female artists with six consecutive number-one studio albums on the Oricon charts since her debut, the others being Japanese singers Ayumi Hamasaki and Hikaru Utada.


title: BoA

text: At age eleven, BoA accompanied her older brother to an SM Entertainment talent search. Though her brother was the one who auditioned as a break-dancer, SM talent scouts instead took notice of BoA and offered her a contract on the same night as the auditions. Her parents initially opposed the notion of BoA leaving school to enter the entertainment business but eventually consented at her older brothers' persuasion. She has said that her early influence as a singer was Seo Taiji.


title: BoA

text: BoA underwent two years of training (involving vocal, dance, English, and Japanese lessons), and at the age of thirteen she released her debut album "ID; Peace B" in South Korea on August 25, 2000. The album was moderately successful; it entered the Top 10 of the South Korean charts and sold around 156,000 units. Meanwhile, her Korean record label, SM Entertainment, made arrangements with Japanese label Avex Trax to launch her music career in Japan. She was forced to quit school to prepare and in early 2001, BoA released her first mini-album, "Don't Start Now"; it sold around 90,000 units. After its release, she took a hiatus from the Korean music industry to focus on the Japanese market at which time she worked to solidify her skills in Japanese.


title: BoA

text: BoA began her Japanese music career singing at the Avex-owned club Velfarre. Her debut Japanese album, "Listen to My Heart", was released on March 13, 2002. The album was a breakthrough in BoA's career, becoming an RIAJ-certified million-seller and debuted atop the Oricon, the first album by a Korean artist to do so. It was promoted with several singles: the Top 20 hit "ID; Peace B" (originally from the eponymous album), "Amazing Kiss", "Kimochi wa Tsutawaru", the Top 5 hit "Listen to My Heart," and the Top 10 "". After the September 11, 2001 attacks, BoA recorded the charity single "The Meaning of Peace" with Kumi Koda as part of Avex's Song Nation project to raise funds for charity. From 2001 to 2007, BoA hosted "Beat it BoA's World", a radio program on the Japan FM Network.


title: BoA

text: After the release of "Listen to My Heart", BoA released her second Korean studio album, "No. 1", a month later on April 12, 2002. The album sold around 544,853 units and became the fourth-best-selling record of the year in South Korea. "Jumping into the World" (a Japanese re-release of the mini-album "Don't Start Now") and the Japanese single "Don't Start Now" were released a month later on the same day. At the end of the year, BoA released her second Korean mini-album "Miracle".


title: BoA

text: BoA's second Japanese studio album, "Valenti" (January 2003), became her best-selling album, with over 1,249,000 copies sold. Three singles preceded its release: "Valenti," which peaked at the number-two position on the Oricon chart, "Kiseki / No.1" and "", both which also peaked at the number-three position. In support of the album, BoA launched "BoA 1st Live Tour Valenti", her first Japanese concert tour. Later in the same year, BoA released her third Korean-language studio album, "Atlantis Princess" on May 30, 2003 and then released a mini-album "Shine We Are!" on December 4, 2003.The former was the fifth-best-selling South Korean record of the year with around 345,000 units sold; the latter sold around 58,000 units.


title: BoA

text: Her third Japanese studio album, "Love & Honesty" (January 2004) was a musical "change in direction": it contained a rock-dance song ("Rock with You") and "harder" R&B. Though the album failed to match "Valenti" in sales, it topped the Oricon chart for two weeks and became RIAJ-certified triple-platinum. In support of the album, BoA held a tour, "Live Concert Tour 2004: Love & Honesty", spanning nine performances and attracted approximately 105,000 attendants. In contrast with "1st Live Tour", which "emphasized exotic Asian design", the "Love & Honesty" tour had an "outer-space, sci-fi" theme; among the props were a three-storey-high space ship and the robot Asimo. Her first compilation album, "Best of Soul" (February 2005), however, sold over a million copies, making BoA the first non-Japanese Asian singer to have two million-selling albums in Japan.


title: BoA

text: BoA reinvented her image for her fourth and fifth Korean albums, "My Name" (June 2004) and "Girls on Top" (June 2005), shedding the "cute" and "youthful" style that had characterized previous years and adopted a more "sexy" and "sultry" look. The sales of BoA's Korean albums began to decline: "My Name" sold 191,000 units and became the eleventh-best-selling South Korean album in 2004 while "Girls on Top" ranked fourteenth in 2005 with 113,000 units sold. In September 2004, BoA instigated controversy in Japan when she donated ₩50 million to a memorial project for Korean independence activist and nationalist An Jung-geun.


title: BoA

text: Her fourth Japanese studio album, "Outgrow", (February 2006) reached the number-one spot on the Oricon chart for its first week of release, making it her fourth consecutive original Japanese album to do so. With 220,000 copies sold, it became her lowest-selling first-week debut for a studio album at that point. "Do the Motion", the first single from the album, reached the top spot, making her the fourth non-Japanese Asian to have a number-one single on the Oricon charts. "Merry Christmas from BoA" (2005), the album's last single, was the singer's first digital single. That May, BoA renewed her contract with SM Entertainment until 2012. At the time it was noted that she had a shareholding in the company of 100,000 (Approximately worth $1m USD). She also voiced Heather the possum in the Korean and Japanese version of the animated film "Over the Hedge". On September 21, 2006, she released her first digital single in Korea, a Korean version of "Key of Heart". In support of "Outgrow", BoA launched a special Zepp tour, B0A The Live, on September 29, 2006, which lasted until October 29. She staged her first Christmas concert on December 7, 2006.


title: BoA

text: Three singles preceded BoA's fifth Japanese studio album, "Made in Twenty" (January 2007): the Top 3 "Nanairo no Ashita (Brand New Beat)/Your Color," the Top 10 "Key of Heart," and the No. 2 hit "Winter Love." The album, which contained R&B and dance songs as well as ballads, debuted at the top of the weekly Oricon charts, making the album her sixth in a row to do so (including one compilation). Having previously compose the song "No More Make Me Sick" for "Made in Twenty", BoA assumed creative control over her sixth Japanese album, "The Face" (February 2008). The album debuted at the top of the weekly Oricon charts, making BoA one of only two artists in Japan to have six consecutive studio albums top the Oricon weekly charts (the other is Ayumi Hamasaki, who has eight consecutive number-one albums). On June 9, 2008, BoA and nine other artists from around the world recorded an English cover of Wei Wei's "Dedication of Love". Produced by Roald Hoffmann and Brian Alan, the single was used to raise funds for victims of the Sichuan earthquake. But due to a tight schedule, BoA was pulled back from this project. Korean jewelry brand Ramee also released, "Ramee by BoA", a line of jewelry designed by the singer herself.


title: BoA

text: On September 2, 2008, it was announced that BoA would make her American debut under a new subsidiary label, SM Entertainment USA. Hoping to become a "world-renowned entertainer" in the vein of Janet Jackson, BoA's debut American single "Eat You Up," was produced by Thomas Troelsen, and released on October 21, 2008. It charted at No. 9 on the "Billboard" Hot Dance Club Play chart. To promote the single, BoA performed "Eat You Up" as well as other songs at YouTube's Tokyo Live concert, and performed in New York City on December 3, 2008, as well as the Jingle Ball at the Anaheim Honda Center on December 6, 2008. The following year, she released "Eien/Universe/Believe in Love" and was also featured in Ravex's single "Believe in Love."


title: BoA

text: BoA's self-titled English album was released in the U.S. on March 17 and featured tracks by producers Bloodshy and Avant as well as a duet with Sean Garrett. Her second Japanese compilation album, "Best & USA" was released on March 18 tying together a compilation of recent hits in Japan with her English-language debut. Though she stated that "[i]t has always been my dream to debut in America," she found English tougher to learn than Japanese and despite living in West Beverly Hills, found it difficult to make friends. BoA later headlined the San Francisco Pride Festival on June 28, 2009, alongside Solange Knowles and The Cliks, where she also performed the song "Energetic" for the first time in public, in addition to "Eat You Up" and "I Did It for Love." On August 31, SM USA released "BoA Deluxe", a repackaged version of her debut English album. The album contained two new tracks and the radio edit version of "Energetic".


title: BoA

text: With her U.S. career struggling to gain traction, BoA returned to East Asia to release her seventh Japanese album, "Identity" (February 2010). Promoted by the singles "Bump Bump!" featuring Verbal from M-Flo and "" (December 2009), the album only charted at No. 4, selling 37,606 copies in its first week. With little promotion from her label, it ended her run of six consecutive No. 1 albums, suggesting that it would be impossible for her to sustain her career in three territories simultaneously. Her first Korean album in five years, "Hurricane Venus," was released on August 5, 2010, and sold 55,776 units making it the 22nd best selling album in South Korea for 2010. She also represented South Korea and performed at the 7th Asia Song Festival, organized by "Korea Foundation for International Culture Exchange", at the Seoul Olympic Stadium.


title: BoA

text: BoA made her Hollywood movie debut in the dance film "Make Your Move 3D", playing the character Aya opposite Derek Hough. Although production ended in 2011, the film was released in 2013. The movie received mixed reviews, with Inkoo Kang of the "Los Angeles Times" praising the choreography but stating that "[w]henever actor Derek Hough and BoA stop leaping and twirling, [it] is an underwritten mess." To celebrate the 10th anniversary of her Japanese debut, BoA released "Milestone," which ranked at No. 4 on the Oricon Weekly Music-DVD charts. She also held her 10th anniversary concert on December 10–11 at Tokyo International Forum.


title: BoA

text: Following the concert, BoA shifted her activities to her native county, joining the judging panel on SBS's audition program "K-pop Star" as a representative of S.M. Entertainment, alongside Yang Hyun-suk from YG Entertainment and Park Jin-young from JYP Entertainment. BoA received praise for her ability as a judge with her insightful comments and discerning eyes, and also sang the theme song "One Dream." For her seventh Korean album, "Only One" (July 2012), BoA wrote and composed its title track, while its dance steps choreographed by NappyTabs, who has previously worked with BoA in "Cobu". Upon its release, "Only One" achieved an all-kill on several music charts. She followed this up with the second "The Shadow," was released August 18, 2012. Additionally, she recorded the song "Lookin'" featuring The Quiett for Hyundai's 'Premium Younique Lifestyle' campaign.


title: BoA

text: BoA launched her first Korean tour with tour at the Olympic Hall, and released the song "Disturbance," which she wrote and composed, to commemorate her first concert tour in South Korea. In September 2013, BoA starred in KBS' two-episode drama special "Expect to Date" alongside Choi Daniel and Im Si-wan, her full first role in a drama, following a string of cameo appearances. She received praise for her acting performance. She also participated in "Infinity Challenge's" bi-annual song festival and was paired with Leessang's Gil, with the two co-produced the song "G.A.B". In March 2014, BoA was appointed as a de facto creative director in S.M. Entertainment, alongside labelmate Kangta; she was placed in charge of mental care of artists who debut at a young age.


title: BoA

text: The singles for BoA's eighth Japanese album, "Who's Back?" (September 2014), were released over a span of four years prior to the album's release:"Woo Weekend" and "I See Me" in 2010, "Milestone" in 2011, Only One," "Tail of Hope" and "Message / Call My Name" in 2013, and "Shout It Out" and "Masayume Chasing" in 2014. To promote the album, she embarked on her BoA Live Tour 2014 Who's Back? tour in September, her first Japanese tour in four years. After the tour concluded, BoA starred in her first Korean film, "Big Match" alongside Lee Jung-jae and Shin Ha-kyun though a Japanese single "Fly" was released on December 3, 2014.


title: BoA

text: Her eighth Korean album "Kiss My Lips" (May 2015) became her first entirely self-written, self-produced album, working alongside American producers The Underdogs and Stereotypes. The single "Who Are You" (feat. Gaeko) was released prior to the album's unveiling, along with its accompanying music video, which starred EXO's Sehun as the male lead. The rest of the album was unveiled on May 12 along with an official music video of the eponymous title track. "Billboard" called the singer a promising songwriter despite moments of musical blandness.


title: BoA

text: In July, she performed at the BoA Special Live 2015: Nowness to commemorate her 15th anniversary. The concert took place on August 22 and 23 at the Sejong Center for the Performing Arts in South Korea, making BoA the first female idol to hold a solo concert at the venue. This was followed by BoA Special Live 2015: Nowness in Japan which took place on December 11, 2015, at Tokyo International Forum Hall-A. Her 15th anniversary in Japan the following year was celebrated in a similar fashion, including the release of the song "Lookbook", and a 15th anniversary edition of BoA's Japanese Winter hit, "Meri Kuri." As part of S.M. Entertainment's special winter project, "Winter Garden," BoA released a digital single entitled "Christmas Paradise."


title: BoA

text: On January 12, 2016, BoA released an English-language single "Make Me Complete", which serves as the theme song for the Fuji TV special drama "Ooku", starring Sawajiri Erika and Watanabe Mayu. In June, she collaborated with Korean rapper Beenzino for S.M. Entertainment's "SM Station" project. The duo released the single "No Matter What," which ranked atop five domestic charts. BoA worked with BeatBurger for another "SM Station" single titled "Music Is Wonderful", where she participated in the composing and writing of the track. From October to November 2016, BoA starred in JTBC's romance melodrama "Listen to Love", returning to the small screen after three years.


title: BoA

text: The following year, BoA became one of the producers for Mnet's boy group survival reality show, "Produce 101 Season 2", which aired from April 7 to June 16. BoA later released another song for "SM Station", "Spring Rain", an R&B number produced by Kenzie. In May, BoA embarked on her BoA The live in "Billboard" Live Tour, held in Tokyo and Osaka. She also released the single "Camo," a dance song with a heavy emphasis on bass and synthesizer sounds, which was a change in sound from her previous materials and produced by The Underdogs. In July, she released the Japanese single "Right Here, Right Everywhere" for the soundtrack of drama "Yaneura no Koibito". She later starred in the film "Autumn Sonata" alongside Lee Hak-joo, playing a terminally ill patient.


title: BoA

text: In 2018, BoA returned to Japan and released her ninth Japanese album "Watashi Konomama de Iinokana" on February 14, 2018, followed by EP "Unchained" in March. To accompany the release of the EP, she embarked on the BoA The Live 2018: Unchained Tour from March 15 to April 4. People who attend the concerts received a copy of "Unchained". On January 31, she released "Nega Dola", which served as a single for BoA's then-upcoming first extended play. The EP, "One Shot, Two Shot", was released on February 20, alongside its titular lead single and the song's music video. The EP peaked at number six at the South Korean Gaon Album Chart and number seven at the "Billboard" World Albums Chart. On October 24, she released her ninth Korean album "Woman" alongside a lead single of the same name. The album peaked at number six at the Gaon Album Chart, number eleven at the "Billboard" World Albums Chart.


title: BoA

text: On June 4, 2019, she released the single "Feedback", which features rapper Nucksal, alongside the song's music video. BoA embarked on her #Mood Tour, which had six dates in Japan and two dates in Seoul, from September to October 2019. On October 23, she released a new Japanese single, "Wishing Well," which she earlier debuted on the tour. On December 11, 2019, she released her second extended play "Starry Night".


title: BoA

text: In May 2020, BoA was featured as one of the coaches for the third season of The Voice of Korea, alongside Dynamic Duo, Sung Si-kyung, and Kim Jong-kook. On December 1, 2020, she released her tenth Korean album "Better". SpoTV News shared BoA to join as a judge for Mnet Dance program "Street Woman Fighter". It is a female dance crew competition premiering in August 2021. On November 5, 2021, BoA released the Japanese single, "My Dear", to commemorate her 20th anniversary.


title: BoA

text: BoA was revealed as a member of the supergroup Got the Beat on December 27, 2021. The group debuted on January 3, 2022.


title: BoA

text: To celebrate her 20th anniversary, BoA released the Japanese compilation album "The Greatest" on May 30, 2022.


title: BoA

text: BoA lists hip hop as her main musical influence, though she also enjoys R&B. Her favorite musicians are Whitney Houston, Michael Jackson, Justin Timberlake, and Ne-Yo; as a result, much of BoA's music is either dance-pop or R&B. Because she also sings ballads, she is often compared to Japanese singers Namie Amuro and Ayumi Hamasaki. Her debut album, "ID; Peace B", contained urban pop, "slickly produced" ballads, and "upbeat dance tunes". As her career went on, she began experimenting with different styles: "Valenti" contained mostly ballads; "Love and Honesty" was an experiment with "harder" R&B and rock music. "The Face" was influenced by electropop and included "happy spring" songs ("Sweet Impact" and "Bad Drive"), a guitar-driven "groovy dance" song ("Lose Your Mind"), and ballads. Because the composition and writing of BoA's songs is handled mostly by her staff, BoA has been criticized as being a "manufactured pop star". In response to such criticism, BoA said that "if one person were to force their own will on something, then things that should have gone right could easily go wrong" and that she is "not all that unhappy with the expression that [she is] a manufactured star. In a way, that is true. Because SM Entertainment created the environment and all the surrounding conditions, [she is] able to be successful in the way [she is] now." She later assumed creative control with "The Face," while "Kiss My Lips" became her first entirely self-written, self-produced album.


title: BoA

text: BoA has collaborated with high-profile artists. Among the Japanese artists she has performed with are the hip hop group M-Flo (for the single "The Love Bug"), pop singer Kumi Koda, and house DJ Mondo Grosso. She has performed with Western artists: the song "Flying Without Wings" from her album "Next World" was a collaboration with Irish band Westlife covering the original song; the Bratz single "Show Me What You Got" was performed with Howie D of the American band Backstreet Boys. She also worked with Akon, singing the song "Beautiful", which was featured on the Japanese release of his third album, "Freedom". Other artists she has collaborated with are Soul'd Out, Dabo, Verbal (of M-Flo), Rah-D, Seamo, TVXQ, Yutaka Furakawa (of the band Doping Panda), and Crystal Kay (for her single ). American rock band Weezer covered "Meri Kuri" on the Japanese version of their album "Weezer".


title: BoA

text: Because of her wide appeal, BoA has appeared in advertisements for many brands. Among the brands she has promoted are Olympus, Lotte, Nike, L'Oréal, Japanese cosmetic company KOSÉ, Skechers, Audio-Technica, GM Daewoo and L'Occitane. Several of her songs have been used in affiliation with television shows. "Every Heart: Minna no Kimochi" was used as the ending theme for the anime "InuYasha"; "Beside You: Boku o Yobu Koe" was used as the opening theme for the anime "Monkey Typhoon"; "Key of Heart" was the theme song for the Japanese release of "Over the Hedge"; "Your Color" was the theme song of the video game "Ninety-Nine Nights"; "Mamoritai: White Wishes" was the theme song of the video game "Tales of Graces,". "Tail of Hope" was used as the theme for the Japanese drama ""Hakui no Namida,"" and "Masayume Chasing" was used as the 15th opening theme song for the anime ""Fairy Tail.""


title: BoA

text: In 2007, Anycall (a Samsung brand) signed BoA, Xiah (of TVXQ), Tablo (of Epik High), and jazz pianist Jin Bora onto "Anyband", a band created specifically to promote Anycall. The band released only one single, "AnyBand". In December 2010, she recorded "I See Me" for to promote Audio Technica headphones in Japan. The song "Woo Weekend" was used to promote Disney on Ice's 25th Anniversary in Japan while "Lookbook" served as the ending theme for the NTV Kei program "Tokui to Goto to Uruwashi no SHELLEY ga Konya Kurabete Mimashita." In August 2017, it was announced that BoA was chosen as promotional ambassador for Jeju Biennale, an inaugural international art event on the resort island of Jeju. In Her widespread popularity has also made her a "cultural ambassador"; she has represented South Korea in inter-Asian musical events and has appeared in an Oxford University Press-published English-language textbook.


title: BoA

text: Dubbed the "Queen of K-pop", BoA is considered one of this century's top artists in East Asia; her popularity in the latter is attributed to her linguistic skills (she speaks and records in Japanese, Korean, and English) and a Japanese interest in Korean pop culture started in the early 2000s when the two countries began promoting cultural exchanges. BoA's popularity extends throughout East Asia; she has fans in China, Hong Kong, Singapore and Taiwan. She had expressed plans to enter a global market; in June 2006, the music video of her Korean song "My Name" became the first music video ever shown on MTV K, an MTV music channel directed at Korean Americans. In 2021, "South China Morning Post" estimated her net worth to be over US$25 million.


title: BoA

text: Though her earlier releases were marked by a "cute" and "youthful" style, BoA began to present a more "mature" image starting from the album "My Name". In a "Talk Asia" interview, Anjali Rao noted that some felt that "My Name" marked the beginning of BoA's decline in popularity and asked if the public would always see the singer as "Little Baby BoA"; BoA replied, "So while I apologize to those people who still want the baby BoA, in fact, what can I do? I just keep growing up! I can't stop that from happening."


title: BoA

text: Various artists have cited BoA as an influence and role model, such as Girls' Generation's Taeyeon, Sunny, Tiffany, Hyoyeon, Seohyun, Shinee's Key, Exo's Sehun, Red Velvet's Irene, I.O.I's Chungha, Billlie's Tsuki, and Aespa's Karina and Winter.


title: Homeostasis

text: In biology, homeostasis (British also homoeostasis) is the state of steady internal, physical, and chemical conditions maintained by living systems. This is the condition of optimal functioning for the organism and includes many variables, such as body temperature and fluid balance, being kept within certain pre-set limits (homeostatic range). Other variables include the pH of extracellular fluid, the concentrations of sodium, potassium and calcium ions, as well as that of the blood sugar level, and these need to be regulated despite changes in the environment, diet, or level of activity. Each of these variables is controlled by one or more regulators or homeostatic mechanisms, which together maintain life.


title: Homeostasis

text: Homeostasis is brought about by a natural resistance to change when already in the optimal conditions, and equilibrium is maintained by many regulatory mechanisms: it is thought to be the central motivation for all organic action. All homeostatic control mechanisms have at least three interdependent components for the variable being regulated: a receptor, a control center, and an effector. The receptor is the sensing component that monitors and responds to changes in the environment, either external or internal. Receptors include thermoreceptors, and mechanoreceptors. Control centers include the respiratory center, and the renin–angiotensin system. An effector is the target acted on, to bring about the change back to the normal state. At the cellular level, effectors include nuclear receptors that bring about changes in gene expression through up-regulation or down-regulation, and act in negative feedback mechanisms. An example of this is in the control of bile acids in the liver.


title: Homeostasis

text: Some centers, such as the renin–angiotensin system, control more than one variable. When the receptor senses a stimulus, it reacts by sending action potentials to a control center. The control center sets the maintenance range—the acceptable upper and lower limits—for the particular variable, such as temperature. The control center responds to the signal by determining an appropriate response and sending signals to an effector, which can be one or more muscles, an organ, or a gland. When the signal is received and acted on, negative feedback is provided to the receptor that stops the need for further signaling.


title: Homeostasis

text: The cannabinoid receptor type 1 (CB1), located at the presynaptic neuron, is a receptor that can stop stressful neurotransmitter release to the postsynaptic neuron; it is activated by endocannabinoids (ECs) such as anandamide ("N"-arachidonoylethanolamide; AEA) and 2-arachidonoylglycerol (2-AG) via a retrograde signaling process in which these compounds are synthesized by and released from postsynaptic neurons, and travel back to the presynaptic terminal to bind to the CB1 receptor for modulation of neurotransmitter release to obtain homeostasis.


title: Homeostasis

text: The polyunsaturated fatty acids (PUFAs) are lipid derivatives of omega-3 (docosahexaenoic acid, DHA, and eicosapentaenoic acid, EPA) or of omega-6 (arachidonic acid, ARA) are synthesized from membrane phospholipids and used as a precursor for endocannabinoids (ECs) mediate significant effects in the fine-tune adjustment of body homeostasis.


title: Homeostasis

text: The word "homeostasis" () uses combining forms of "homeo-" and "-stasis", New Latin from Greek: ὅμοιος "homoios", "similar" and στάσις "stasis", "standing still", yielding the idea of "staying the same".


title: Homeostasis

text: The concept of the regulation of the internal environment was described by French physiologist Claude Bernard in 1849, and the word "homeostasis" was coined by Walter Bradford Cannon in 1926. In 1932, Joseph Barcroft a British physiologist, was the first to say that higher brain function required the most stable internal environment. Thus, to Barcroft homeostasis was not only organized by the brain—homeostasis served the brain. Homeostasis is an almost exclusively biological term, referring to the concepts described by Bernard and Cannon, concerning the constancy of the internal environment in which the cells of the body live and survive. The term cybernetics is applied to technological control systems such as thermostats, which function as homeostatic mechanisms, but is often defined much more broadly than the biological term of homeostasis.


title: Homeostasis

text: The metabolic processes of all organisms can only take place in very specific physical and chemical environments. The conditions vary with each organism, and with whether the chemical processes take place inside the cell or in the interstitial fluid bathing the cells. The best known homeostatic mechanisms in humans and other mammals are regulators that keep the composition of the extracellular fluid (or the "internal environment") constant, especially with regard to the temperature, pH, osmolality, and the concentrations of sodium, potassium, glucose, carbon dioxide, and oxygen. However, a great many other homeostatic mechanisms, encompassing many aspects of human physiology, control other entities in the body. Where the levels of variables are higher or lower than those needed, they are often prefixed with "hyper-" and "hypo-", respectively such as hyperthermia and hypothermia or hypertension and hypotension.


title: Homeostasis

text: If an entity is homeostatically controlled it does not imply that its value is necessarily absolutely steady in health. Core body temperature is, for instance, regulated by a homeostatic mechanism with temperature sensors in, amongst others, the hypothalamus of the brain. However, the set point of the regulator is regularly reset. For instance, core body temperature in humans varies during the course of the day (i.e. has a circadian rhythm), with the lowest temperatures occurring at night, and the highest in the afternoons. Other normal temperature variations include those related to the menstrual cycle. The temperature regulator's set point is reset during infections to produce a fever. Organisms are capable of adjusting somewhat to varied conditions such as temperature changes or oxygen levels at altitude, by a process of acclimatisation.


title: Homeostasis

text: Homeostasis does not govern every activity in the body. For instance the signal (be it via neurons or hormones) from the sensor to the effector is, of necessity, highly variable in order to convey information about the direction and magnitude of the error detected by the sensor. Similarly the effector's response needs to be highly adjustable to reverse the error – in fact it should be very nearly in proportion (but in the opposite direction) to the error that is threatening the internal environment. For instance, the arterial blood pressure in mammals is homeostatically controlled, and measured by stretch receptors in the walls of the aortic arch and carotid sinuses at beginnings of the internal carotid arteries. The sensors send messages via sensory nerves to the medulla oblongata of the brain indicating whether the blood pressure has fallen or risen, and by how much. The medulla oblongata then distributes messages along motor or efferent nerves belonging to the autonomic nervous system to a wide variety of effector organs, whose activity is consequently changed to reverse the error in the blood pressure. One of the effector organs is the heart whose rate is stimulated to rise (tachycardia) when the arterial blood pressure falls, or to slow down (bradycardia) when the pressure rises above set point. Thus the heart rate (for which there is no sensor in the body) is not homeostatically controlled, but is one of effector responses to errors in the arterial blood pressure. Another example is the rate of sweating. This is one of the effectors in the homeostatic control of body temperature, and therefore highly variable in rough proportion to the heat load that threatens to destabilize the body's core temperature, for which there is a sensor in the hypothalamus of the brain.


title: Homeostasis

text: Mammals regulate their core temperature using input from thermoreceptors in the hypothalamus, brain, spinal cord, internal organs, and great veins. Apart from the internal regulation of temperature, a process called allostasis can come into play that adjusts behaviour to adapt to the challenge of very hot or cold extremes (and to other challenges). These adjustments may include seeking shade and reducing activity, or seeking warmer conditions and increasing activity, or huddling.


title: Homeostasis

text: Behavioural thermoregulation takes precedence over physiological thermoregulation since necessary changes can be affected more quickly and physiological thermoregulation is limited in its capacity to respond to extreme temperatures.


title: Homeostasis

text: When core temperature falls, the blood supply to the skin is reduced by intense vasoconstriction. The blood flow to the limbs (which have a large surface area) is similarly reduced, and returned to the trunk via the deep veins which lie alongside the arteries (forming venae comitantes). This acts as a counter-current exchange system which short-circuits the warmth from the arterial blood directly into the venous blood returning into the trunk, causing minimal heat loss from the extremities in cold weather. The subcutaneous limb veins are tightly constricted, not only reducing heat loss from this source, but also forcing the venous blood into the counter-current system in the depths of the limbs.


title: Homeostasis

text: The metabolic rate is increased, initially by non-shivering thermogenesis, followed by shivering thermogenesis if the earlier reactions are insufficient to correct the hypothermia.


title: Homeostasis

text: When core temperature rises are detected by thermoreceptors, the sweat glands in the skin are stimulated via cholinergic sympathetic nerves to secrete sweat onto the skin, which, when it evaporates, cools the skin and the blood flowing through it. Panting is an alternative effector in many vertebrates, which cools the body also by the evaporation of water, but this time from the mucous membranes of the throat and mouth.


title: Homeostasis

text: Blood sugar levels are regulated within fairly narrow limits. In mammals the primary sensors for this are the beta cells of the pancreatic islets. The beta cells respond to a rise in the blood sugar level by secreting insulin into the blood, and simultaneously inhibiting their neighboring alpha cells from secreting glucagon into the blood. This combination (high blood insulin levels and low glucagon levels) act on effector tissues, chief of which are the liver, fat cells and muscle cells. The liver is inhibited from producing glucose, taking it up instead, and converting it to glycogen and triglycerides. The glycogen is stored in the liver, but the triglycerides are secreted into the blood as very low-density lipoprotein (VLDL) particles which are taken up by adipose tissue, there to be stored as fats. The fat cells take up glucose through special glucose transporters (GLUT4), whose numbers in the cell wall are increased as a direct effect of insulin acting on these cells. The glucose that enters the fat cells in this manner is converted into triglycerides (via the same metabolic pathways as are used by the liver) and then stored in those fat cells together with the VLDL-derived triglycerides that were made in the liver. Muscle cells also take glucose up through insulin-sensitive GLUT4 glucose channels, and convert it into muscle glycogen.


title: Homeostasis

text: A fall in blood glucose, causes insulin secretion to be stopped, and glucagon to be secreted from the alpha cells into the blood. This inhibits the uptake of glucose from the blood by the liver, fats cells and muscle. Instead the liver is strongly stimulated to manufacture glucose from glycogen (through glycogenolysis) and from non-carbohydrate sources (such as lactate and de-aminated amino acids) using a process known as gluconeogenesis. The glucose thus produced is discharged into the blood correcting the detected error (hypoglycemia). The glycogen stored in muscles remains in the muscles, and is only broken down, during exercise, to glucose-6-phosphate and thence to pyruvate to be fed into the citric acid cycle or turned into lactate. It is only the lactate and the waste products of the citric acid cycle that are returned to the blood. The liver can take up only the lactate, and by the process of energy consuming gluconeogenesis convert it back to glucose.


title: Homeostasis

text: Copper is absorbed, transported, distributed, stored, and excreted in the body according to complex homeostatic processes which ensure a constant and sufficient supply of the micronutrient while simultaneously avoiding excess levels. If an insufficient amount of copper is ingested for a short period of time, copper stores in the liver will be depleted. Should this depletion continue, a copper health deficiency condition may develop. If too much copper is ingested, an excess condition can result. Both of these conditions, deficiency and excess, can lead to tissue injury and disease. However, due to homeostatic regulation, the human body is capable of balancing a wide range of copper intakes for the needs of healthy individuals.


title: Homeostasis

text: Many aspects of copper homeostasis are known at the molecular level. Copper's essentiality is due to its ability to act as an electron donor or acceptor as its oxidation state fluxes between Cu(cuprous) and Cu (cupric). As a component of about a dozen cuproenzymes, copper is involved in key redox (i.e., oxidation-reduction) reactions in essential metabolic processes such as mitochondrial respiration, synthesis of melanin, and cross-linking of collagen. Copper is an integral part of the antioxidant enzyme copper-zinc superoxide dismutase, and has a role in iron homeostasis as a cofactor in ceruloplasmin.


title: Homeostasis

text: Changes in the levels of oxygen, carbon dioxide, and plasma pH are sent to the respiratory center, in the brainstem where they are regulated.


title: Homeostasis

text: The partial pressure of oxygen and carbon dioxide in the arterial blood is monitored by the peripheral chemoreceptors (PNS) in the carotid artery and aortic arch. A change in the partial pressure of carbon dioxide is detected as altered pH in the cerebrospinal fluid by central chemoreceptors (CNS) in the medulla oblongata of the brainstem. Information from these sets of sensors is sent to the respiratory center which activates the effector organs – the diaphragm and other muscles of respiration. An increased level of carbon dioxide in the blood, or a decreased level of oxygen, will result in a deeper breathing pattern and increased respiratory rate to bring the blood gases back to equilibrium.


title: Homeostasis

text: Too little carbon dioxide, and, to a lesser extent, too much oxygen in the blood can temporarily halt breathing, a condition known as apnea, which freedivers use to prolong the time they can stay underwater.


title: Homeostasis

text: The partial pressure of carbon dioxide is more of a deciding factor in the monitoring of pH. However, at high altitude (above 2500 m) the monitoring of the partial pressure of oxygen takes priority, and hyperventilation keeps the oxygen level constant. With the lower level of carbon dioxide, to keep the pH at 7.4 the kidneys secrete hydrogen ions into the blood, and excrete bicarbonate into the urine. This is important in the acclimatization to high altitude.


title: Homeostasis

text: The kidneys measure the oxygen content rather than the partial pressure of oxygen in the arterial blood. When the oxygen content of the blood is chronically low, oxygen-sensitive cells secrete erythropoietin (EPO) into the blood. The effector tissue is the red bone marrow which produces red blood cells (RBCs)(erythrocytes). The increase in RBCs leads to an increased hematocrit in the blood, and subsequent increase in hemoglobin that increases the oxygen carrying capacity. This is the mechanism whereby high altitude dwellers have higher hematocrits than sea-level residents, and also why persons with pulmonary insufficiency or right-to-left shunts in the heart (through which venous blood by-passes the lungs and goes directly into the systemic circulation) have similarly high hematocrits.


title: Homeostasis

text: Regardless of the partial pressure of oxygen in the blood, the amount of oxygen that can be carried, depends on the hemoglobin content. The partial pressure of oxygen may be sufficient for example in anemia, but the hemoglobin content will be insufficient and subsequently as will be the oxygen content. Given enough supply of iron, vitamin B12 and folic acid, EPO can stimulate RBC production, and hemoglobin and oxygen content restored to normal.


title: Homeostasis

text: The brain can regulate blood flow over a range of blood pressure values by vasoconstriction and vasodilation of the arteries.


title: Homeostasis

text: High pressure receptors called baroreceptors in the walls of the aortic arch and carotid sinus (at the beginning of the internal carotid artery) monitor the arterial blood pressure. Rising pressure is detected when the walls of the arteries stretch due to an increase in blood volume. This causes heart muscle cells to secrete the hormone atrial natriuretic peptide (ANP) into the blood. This acts on the kidneys to inhibit the secretion of renin and aldosterone causing the release of sodium, and accompanying water into the urine, thereby reducing the blood volume.


title: Homeostasis

text: This information is then conveyed, via afferent nerve fibers, to the solitary nucleus in the medulla oblongata. From here motor nerves belonging to the autonomic nervous system are stimulated to influence the activity of chiefly the heart and the smallest diameter arteries, called arterioles. The arterioles are the main resistance vessels in the arterial tree, and small changes in diameter cause large changes in the resistance to flow through them. When the arterial blood pressure rises the arterioles are stimulated to dilate making it easier for blood to leave the arteries, thus deflating them, and bringing the blood pressure down, back to normal. At the same time, the heart is stimulated via cholinergic parasympathetic nerves to beat more slowly (called bradycardia), ensuring that the inflow of blood into the arteries is reduced, thus adding to the reduction in pressure, and correction of the original error.


title: Homeostasis

text: Low pressure in the arteries, causes the opposite reflex of constriction of the arterioles, and a speeding up of the heart rate (called tachycardia). If the drop in blood pressure is very rapid or excessive, the medulla oblongata stimulates the adrenal medulla, via "preganglionic" sympathetic nerves, to secrete epinephrine (adrenaline) into the blood. This hormone enhances the tachycardia and causes severe vasoconstriction of the arterioles to all but the essential organ in the body (especially the heart, lungs, and brain). These reactions usually correct the low arterial blood pressure (hypotension) very effectively.


title: Homeostasis

text: The plasma ionized calcium (Ca) concentration is very tightly controlled by a pair of homeostatic mechanisms. The sensor for the first one is situated in the parathyroid glands, where the chief cells sense the Ca level by means of specialized calcium receptors in their membranes. The sensors for the second are the parafollicular cells in the thyroid gland. The parathyroid chief cells secrete parathyroid hormone (PTH) in response to a fall in the plasma ionized calcium level; the parafollicular cells of the thyroid gland secrete calcitonin in response to a rise in the plasma ionized calcium level.


title: Homeostasis

text: The effector organs of the first homeostatic mechanism are the bones, the kidney, and, via a hormone released into the blood by the kidney in response to high PTH levels in the blood, the duodenum and jejunum. Parathyroid hormone (in high concentrations in the blood) causes bone resorption, releasing calcium into the plasma. This is a very rapid action which can correct a threatening hypocalcemia within minutes. High PTH concentrations cause the excretion of phosphate ions via the urine. Since phosphates combine with calcium ions to form insoluble salts (see also bone mineral), a decrease in the level of phosphates in the blood, releases free calcium ions into the plasma ionized calcium pool. PTH has a second action on the kidneys. It stimulates the manufacture and release, by the kidneys, of calcitriol into the blood. This steroid hormone acts on the epithelial cells of the upper small intestine, increasing their capacity to absorb calcium from the gut contents into the blood.


title: Homeostasis

text: The second homeostatic mechanism, with its sensors in the thyroid gland, releases calcitonin into the blood when the blood ionized calcium rises. This hormone acts primarily on bone, causing the rapid removal of calcium from the blood and depositing it, in insoluble form, in the bones.


title: Homeostasis

text: The two homeostatic mechanisms working through PTH on the one hand, and calcitonin on the other can very rapidly correct any impending error in the plasma ionized calcium level by either removing calcium from the blood and depositing it in the skeleton, or by removing calcium from it. The skeleton acts as an extremely large calcium store (about 1 kg) compared with the plasma calcium store (about 180 mg). Longer term regulation occurs through calcium absorption or loss from the gut.


title: Homeostasis

text: Another example are the most well-characterised endocannabinoids like anandamide ("N"-arachidonoylethanolamide; AEA) and 2-arachidonoylglycerol (2-AG), whose synthesis occurs through the action of a series of intracellular enzymes activated in response to a rise in intracellular calcium levels to introduce homeostasis and prevention of tumor development through putative protective mechanisms that prevent cell growth and migration by activation of CB1 and/or CB2 and adjoining receptors.


title: Homeostasis

text: The homeostatic mechanism which controls the plasma sodium concentration is rather more complex than most of the other homeostatic mechanisms described on this page.


title: Homeostasis

text: The sensor is situated in the juxtaglomerular apparatus of kidneys, which senses the plasma sodium concentration in a surprisingly indirect manner. Instead of measuring it directly in the blood flowing past the juxtaglomerular cells, these cells respond to the sodium concentration in the renal tubular fluid after it has already undergone a certain amount of modification in the proximal convoluted tubule and loop of Henle. These cells also respond to rate of blood flow through the juxtaglomerular apparatus, which, under normal circumstances, is directly proportional to the arterial blood pressure, making this tissue an ancillary arterial blood pressure sensor.


title: Homeostasis

text: In response to a lowering of the plasma sodium concentration, or to a fall in the arterial blood pressure, the juxtaglomerular cells release renin into the blood. Renin is an enzyme which cleaves a decapeptide (a short protein chain, 10 amino acids long) from a plasma α-2-globulin called angiotensinogen. This decapeptide is known as angiotensin I. It has no known biological activity. However, when the blood circulates through the lungs a pulmonary capillary endothelial enzyme called angiotensin-converting enzyme (ACE) cleaves a further two amino acids from angiotensin I to form an octapeptide known as angiotensin II. Angiotensin II is a hormone which acts on the adrenal cortex, causing the release into the blood of the steroid hormone, aldosterone. Angiotensin II also acts on the smooth muscle in the walls of the arterioles causing these small diameter vessels to constrict, thereby restricting the outflow of blood from the arterial tree, causing the arterial blood pressure to rise. This, therefore, reinforces the measures described above (under the heading of "Arterial blood pressure"), which defend the arterial blood pressure against changes, especially hypotension.


title: Homeostasis

text: The angiotensin II-stimulated aldosterone released from the zona glomerulosa of the adrenal glands has an effect on particularly the epithelial cells of the distal convoluted tubules and collecting ducts of the kidneys. Here it causes the reabsorption of sodium ions from the renal tubular fluid, in exchange for potassium ions which are secreted from the blood plasma into the tubular fluid to exit the body via the urine. The reabsorption of sodium ions from the renal tubular fluid halts further sodium ion losses from the body, and therefore preventing the worsening of hyponatremia. The hyponatremia can only be "corrected" by the consumption of salt in the diet. However, it is not certain whether a "salt hunger" can be initiated by hyponatremia, or by what mechanism this might come about.


title: Homeostasis

text: When the plasma sodium ion concentration is higher than normal (hypernatremia), the release of renin from the juxtaglomerular apparatus is halted, ceasing the production of angiotensin II, and its consequent aldosterone-release into the blood. The kidneys respond by excreting sodium ions into the urine, thereby normalizing the plasma sodium ion concentration. The low angiotensin II levels in the blood lower the arterial blood pressure as an inevitable concomitant response.


title: Homeostasis

text: The reabsorption of sodium ions from the tubular fluid as a result of high aldosterone levels in the blood does not, of itself, cause renal tubular water to be returned to the blood from the distal convoluted tubules or collecting ducts. This is because sodium is reabsorbed in exchange for potassium and therefore causes only a modest change in the osmotic gradient between the blood and the tubular fluid. Furthermore, the epithelium of the distal convoluted tubules and collecting ducts is impermeable to water in the absence of antidiuretic hormone (ADH) in the blood. ADH is part of the control of fluid balance. Its levels in the blood vary with the osmolality of the plasma, which is measured in the hypothalamus of the brain. Aldosterone's action on the kidney tubules prevents sodium loss to the extracellular fluid (ECF). So there is no change in the osmolality of the ECF, and therefore no change in the ADH concentration of the plasma. However, low aldosterone levels cause a loss of sodium ions from the ECF, which could potentially cause a change in extracellular osmolality and therefore of ADH levels in the blood.