The F region of the ionosphere is home to the F layer of ionization called the Appleton–Barnett layer, after the English physicist Edward Appleton and New Zealand physicist and meteorologist Miles Barnett. As with other ionospheric sectors,'layer' implies a concentration of plasma, while'region' is the volume that contains the said layer; the F region contains ionized gases at a height of around 150–800 km above sea level, placing it in the Earth's thermosphere, a hot region in the upper atmosphere, in the heterosphere, where chemical composition varies with height. Speaking, the F region has the highest concentration of free electrons and ions anywhere in the atmosphere, it may be thought of as comprising the F1-and F2-layers. The F-region is located directly below the protonosphere, it acts as a dependable reflector of HF radio signals as it is not affected by atmospheric conditions, although its ionic composition varies with the sunspot cycle. It reflects normal-incident frequencies at or below the critical frequency and absorbs waves of higher frequency.

The F1 layer is the lower sector of the F layer and exists from about 150 to 220 km above the surface of the Earth and only during daylight hours. It is composed of a mixture of molecular ions O2+ and NO+, atomic ions O+. Above the F1 region, atomic oxygen becomes the dominant constituent because lighter particles tend to occupy higher altitudes above the turbopause; this atomic oxygen provides the O + atomic ions. The F1 layer has 5 × 105 e/cm3 at noontime and minimum sunspot activity, increases to 2 × 106 e/cm3 during maximum sunspot activity; the density falls off to below 104 e/cm3 at night. The F1 layer merges into the F2 layer at night. Though regular in its characteristics, it is not observable everywhere or on all days; the principal reflecting layer during the summer for paths of 2,000 to 3,500 km is the F1 layer. However, this depends upon the frequency of a propagating signal; the E layer electron density and resultant MUF, maximum usable frequency, during high solar activity periods can refract and thus block signals of up to about 15 MHz from reaching the F1 and F2 regions, with the result that distances are much shorter than possible with refractions from the F1 and F2 regions.

But low radiation-angle signals can reach distances of 3000 km via E region refractions. The F2 layer exists from about 220 to 800 km above the surface of the Earth; the F2 layer is the principal reflecting layer for HF communications during both night. The horizon-limited distance for one-hop F2 propagation is around 4,000 km; the F2 layer has about 106 e/cm3. However, variations are large and pronounced during magnetic storms; the F layer behaviour is dominated by the complex thermospheric winds. Critical F2 layer frequencies are the ones; this article incorporates public domain material from the General Services Administration document: "Federal Standard 1037C"

The relationship between Uruguay and the International Monetary Fund began when Uruguay joined the IMF The IMF is an international organization founded in 1944 as part of the Bretton Woods Conference. Its primary purpose is to increase financial stability in member countries, with financial means ranging from loans to credit offers. Uruguay is a country in South America, it is a member of the IMF. The economy of Uruguay is diverse, with 7.5% of Gross domestic product originating from agriculture, 10% from tourism and 20.6% from industry. As of 2017, Uruguay had the ninth largest GDP in the 96th globally. Uruguay is a beneficiary of IMF intervention, although it has not undergone any of the substantial macroeconomic changes mandated by the IMF and no projects have been completed there. However, multiple arrangements have been made for the IMF to provide the country with standby credit, the first of, arranged in 1996; this is in line with the institution's goal of supporting economic stability. These standby credit lines started during a time of significant economic growth, but at a time of heavy dollarization.

For context, as of 2008, 60% of Uruguay's bank loans use U. S. Dollars as opposed to the national currency, the Uruguayan peso. In general, these stand-by arrangements have been available for terms of one to two years, each valued in the range of 150 - 2000 SDR. Additionally, the Uruguayan government has utilized 72% of funds made available to them between 2000 and 2006, the last arrangement expiring in December 2006; as of May 2017, the Uruguayan government owes 380,000 SDR to the IMF, which represents less than 0.00001% of the GDP, standing at US$53.44 billion as of June 2017. In concert with these stand-by arrangements, the Uruguayan government has been successful in its implementation of a “gradual anti-inflation strategy” started in the 1990s. Inflation has slowed to 9% in 2017, versus a peak of 140%. However, it is greater than the government's goal of 6%. In addition, Uruguay maintains a high degree of liquidity; the IMF speculated that an economic downturn in neighbouring countries Argentina and Brazil, as well as a slowdown in China, are contributing factors to Uruguay's slowed economic growth.

Despite this, Uruguay's heavy utilization of IMF credit has been correlated with its lasting stability in the South American region. Additionally, Uruguay has been able to keep pace with, or in some cases outperform, the GDP growth rate of neighbouring countries: Brazil and Argentina. IMF chief Christine Lagarde warns of'dark future' over climate change

Joan Carol Warnow-Blewett was an American archivist and staff member of the American Institute of Physics for 32 years. Warnow-Blewett was born to parents David Nelson and Edith Nelson, American immigrants who were born in Sweden. In 1965, Warnow-Blewett was hired at American Institute of Physics as Librarian of the Niels Bohr Library. In 1974, she was promoted to Associate Director for the Center for History of Physics. From 1986 to 1989, she was a council member of the Society of American Archivists. Warnow-Blewett's work was a significant influence on the book, Structures of Scientific Collaboration by Wesley Shrum, Joel Genuth and Ivan Chompalov. Starting in 1989, she assembled a multi-disciplinary team including social sciences and archives; this team collected data on 60 scientific collaborations over the span of a decade. They coded the interviews with the collaborative teams in order to create a massive database covering themes such as "invention and practice. Warnow-Blewett was married three times.

Her first marriage, until 1964, was to inventor Morton Warnow, with whom she had three children. In 1983, she married physicist John Paul Blewett and was married to Blewett until his death in 2000, her third marriage was to Martin Klein. Warnow-Blewett died in Alamo, California, on May 30, 2006, she was survived by three children, Paul Warnow, Kimmen Sjolander, Tandy Warnow. Between 1970 and 2001, Warnow-Blewett published 60 works in 105 publications, she continued to publish after her retirement from the AIP in August 1997. Selected notable publications Warnow-Blewett, Joan. AIP Study of Multi-Institutional Collaborations. Final Report Documenting Multi-Institutional Collaborations. College Park, MD: Center for History of Physics, American Institute of Physics. OCLC 47204030. Warnow-Blewett, Joan. Guide to Sources for History of Solid State Physics, Report No. 6. New York: Center for History of Physics, American Institute of Physics. ISBN 978-1-56-396068-0. OCLC 27761357. Warnow-Blewett, Joan. Guidelines for Records Appraisal at Major Research Facilities: Selection of Permanent Records of DOE Laboratories.

Institutional Management and Policy, Physics Research. New York: Center for History of Physics, American Institute of Physics. OCLC 13356678

Prisoner of Love is Jean Genet's final book, posthumously published from manuscripts he was working on at the time of his death. Under its French title, Un Captif Amoureux, the book was first published in Paris by Gallimard in May 1986. Translated into English by Barbara Bray and with an introduction by Edmund White it was published by Picador. Prisoner of Love was subsequently published in 2003 by New York Review Books. with a new lengthy introduction by Ahdaf Soueif. The book is a memoir of Genet's encounters with Black Panthers. Starting in 1970, he had spent two years in the Palestinian refugee camps in Jordan. Visiting Beirut in September 1982, he found himself in the midst of the Israeli invasion of the city, he was one of the first foreigners to enter Shatila refugee camp after the massacre of hundreds of its inhabitants. According to Edmund White, "For a book about one of the most ideologically heated conflicts of modern times, Prisoner of Love is curiously cool and unpolemical." As described by Publishers Weekly, "Part anti-Zionist tract, part memoir and philosophical discourse, this uninhibited cascade of images and associations is less a political document than a map of Genet's mental landscape."

Edward Said in The Observer called it "one of the strangest and most extraordinary books of the decade", the Washington Post Book World review said: "Written with pain’s steel nib, it is a product of long incubation and philosophical and Proustian." For the Los Angeles Reader, it is "An undeniable masterpiece, written with assurance and the fine white heat of lifelong rage." 1995 Prisoner of Love was staged as a performance piece by JoAnne Akalaitis at the New York Theatre Workshop from 12 May to 25 June 1995, with an original score composed by Philip Glass. Martin Kramer, "Prisoner of Hate: Jean Genet and Palestine". Review of Edmund White, Genet: A Biography, published in Commentary, July 1994, pp. 46–49

The Hungarian House of New York, founded in 1966, serves Hungarian communities of New York City as an independent cultural institution. It is located at New York City in the Upper East Side, it hosts and organises weekly as well as single events, gives place to a Hungarian library and to the János Arany Hungarian School. Five members of the Hungarian community – Peter Schell, Ede Neuman de Végvár, Károly Pulvári, Ferenc Chorin and Tibor Eckhardt, operating within the framework of the Széchenyi István Society, the Hungarian Catholic League, the American Hungarian Library and Historical Society – established the American Foundation for Hungarian Literature and Education on August 23, 1963, registered as a non-profit organization by the State of New York on April 16, 1964. With the generous support of their founding members, the three organizations purchased the building of the future Hungarian House from the German athletic club Central Turnverein of the City of New York at 213-215 East 82nd Street on September 9, 1966, when the AFHLE assumed responsibility for its maintenance.

Over the years, the Catholic League handed over its ownership rights to local Hungarian Franciscans, who in turn passed it on to the Hungarian Scout Association in Exteris, the third co-owner organization since. So today the Hungarian House of New York is owned by three non-profit organizations: the American Hungarian Library and Historical Society, the Hungarian Scout Association in Exteris, the Széchenyi István Society; the founders of the Hungarian House made sure the House would always stay in the hands of the Hungarian community. According to the Articles of Incorporation, the co-owners can only pass on ownership rights to organizations with similar objectives, with the consent of the other two co-owners. Furthermore, in the event the AFHLE were to be dissolved and the Hungarian House sold, none of the co-owners shall benefit from the proceeds, the entire amount is to be offered to organizations engaged in Hungarian scientific and cultural activities; as one of the central community establishments of Hungarian immigrants in New York, the Hungarian House has welcomed numerous leading personalities over the years.

It was among these walls that József Antall, the first democratically elected Prime Minister of Hungary after the fall of Communism in 1989, greeted the Hungarian-American community, as did Presidents Árpád Göncz and Pál Schmitt, Cardinal József Mindszenty Prince Primate of Hungary, Member of the European Parliament Otto von Habsburg, nuclear physicist Edward Teller, Nobel laureate physicist Dennis Gábor, Cardinal Péter Erdő Primate of Hungary, László Kövér President of the Hungarian Parliament. From the beginning, thanks to the work of hundreds of generous supporters and volunteers, thousands of visitors could learn about slices of Hungarian culture in the Hungarian House. Numerous lectures, film screenings, folk dances, fairs, gatherings and English language classes took place in these halls, all of them serving both the Hungarian émigrés and the host country. Between 1974 and 1975, 24 Hungarian organizations utilized the Hungarian House, according to the minutes of the AFHLE; the website of the Hungarian House of New York The Facebook-page of the Hungarian House of New York The website of the Hungarian Scout Association in Exteris The website of the Széchenyi István Society The website of the American Hungarian Library and Historical Society The website of the János Arany Hungarian School

Rosina Lhévinne was a pianist and famed pedagogue. Rosina Bessie was the younger of two daughters of Maria and Jacques Bessie, a prosperous jeweller from a Dutch Jewish family who emigrated to the Russian Empire to ply his trade as a diamond merchant. There were violent anti-Semitic riots in Kiev during her first year, the Bessies moved to Moscow in 1881 or 1882; the young Rosina began studying piano at the age of six with a teacher in Moscow, where the family had moved shortly after her birth. When her teacher became ill, a family friend suggested that she continue her studies with Josef Lhévinne, a talented student at the Moscow Imperial Conservatory, five years older than Rosina, she showed great talent and several years was admitted to the Conservatory, where she studied with Lhévinne's teacher, Vasily Safonov. At her graduation in 1898, she won the Gold Medal in piano as had Josef before her, that year the two were married, they had Constantine "Don" Lhevinne and Marianna Lhevinne Graham.

Rosina gave up her ambitions to be a solo performer to avoid clashing with her husband Josef's career as a concert pianist, a vow she kept until well after his death in 1944. Thus she confined her activities to performing on two pianos with her husband. Together they lived and taught in Moscow, Georgia and in Berlin before emigrating after World War I and the Russian Revolution to New York, where they joined the faculty of the Institute of Musical Art which became The Juilliard School. Having acted as a preparatory teacher to her more famous husband's students for 46 years, she felt reluctant after his death to assume his full duties at the school. Among her students were many of the best young pianists of the 1940s, 50s and 60s, including Van Cliburn, who arrived in her class in 1951. At the height of the Cold War in 1958, he was awarded the First Prize at the inaugural Tchaikovsky Competition in Moscow becoming an instant worldwide celebrity and bringing international fame to his teacher.

Other Lhévinne students include James Levine, Music Director of the Metropolitan Opera, John Williams and conductor of the Boston Pops Orchestra, the composer Judith Lang Zaimont, pianists John Browning, Walter Buczynski, Seth Carlin, Eduardo Delgado, Madeleine Forte, Edna Golandsky, Tong-Il Han, Anthony & Joseph Paratore, Daniel Pollack, Marcus Raskin, Misha Dichter, Edward Auer, Santos Ojeda, Joel Ryce-Menuhin, Garrick Ohlsson, Joseph William Fennimore, Hiroko Nakamura, Neal Larrabee, many others including several present-day teachers at the Juilliard School. In 1949 Mme. Lhévinne reconsidered her decision never to play in public as a soloist, in her 70s and 80s she made a remarkable series of appearances, first in collaboration with the Juilliard String Quartet, in concertos at the Aspen Summer Music Festival, her greatest moment as a soloist came in January 1963, aged 82, with her debut at the New York Philharmonic under conductor Leonard Bernstein playing Frédéric Chopin's Piano Concerto No.

1, a piece she had performed for her graduation from the Moscow Conservatory sixty-five years earlier. There are recordings of both the Chopin Concerto and Mozart's C major Concerto, K. 467. Madame Lhévinne continued to teach at Juilliard and at the University of Southern California in Los Angeles where she died in 1976 at age 96. Just prior to her death, Robert K. Wallace published a book about the Lhévinnes entitled A Century of Music-Making: The Lives of Josef and Rosina Lhévinne, for which she was extensively interviewed. In 2003, Madame Lhévinne's former student and assistant, Salome Ramras Arkatov, produced a documentary film, The Legacy of Rosina Lhévinne, which contains rare archival footage of Lhévinne's teaching and performing as well as interviews with a number of her former students. Rosina Lhévinne | Jewish Women's Archive Arkatov Productions - The Legacy of Rosina Lhevinne http://www.naxos.com/person/Rosina_Lhevinne/2230.htm The Rosina Lhevinne papers in the Music Division of The New York Public Library for the Performing Arts