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Mesoscopic physics

Disambiguation: This page refers to the sub-discipline of condensed matter physics, not the branch of mesoscale meteorology concerned with the study of weather systems smaller than synoptic scale systems. Mesoscopic physics is a subdiscipline of condensed matter physics that deals with materials of an intermediate length; these materials range in size between the nanoscale for a quantity of atoms and of materials measuring micrometres. The lower limit can be defined as being the size of individual atoms. At the micrometre level are bulk materials. Both mesoscopic and macroscopic objects contain many atoms. Whereas average properties derived from its constituent materials describe macroscopic objects, as they obey the laws of classical mechanics, a mesoscopic object, by contrast, is affected by thermal fluctuations around the average, its electronic behavior may require modeling at the level of quantum mechanics. A macroscopic electronic device, when scaled down to a meso-size, starts revealing quantum mechanical properties.

For example, at the macroscopic level the conductance of a wire increases continuously with its diameter. However, at the mesoscopic level, the wire's conductance is quantized: the increases occur in discrete, or individual, whole steps. During research, mesoscopic devices are constructed and observed experimentally and theoretically in order to advance understanding of the physics of insulators, semiconductors and superconductors; the applied science of mesoscopic physics deals with the potential of building nanodevices. Mesoscopic physics addresses fundamental practical problems which occur when a macroscopic object is miniaturized, as with the miniaturization of transistors in semiconductor electronics; the mechanical and electronic properties of materials change as their size approaches the nanoscale, where the percentage of atoms at the surface of the material becomes significant. For bulk materials larger than one micrometre, the percentage of atoms at the surface is insignificant in relation to the number of atoms in the entire material.

The subdiscipline has dealt with artificial structures of metal or semiconducting material which have been fabricated by the techniques employed for producing microelectronic circuits. There is no rigid definition for mesoscopic physics but the systems studied are in the range of 100 nm to 1 000 nm: 100 nanometers is the approximate upper limit for a nanoparticle. Thus, mesoscopic physics has a close connection to the fields of nanotechnology. Devices used in nanotechnology are examples of mesoscopic systems. Three categories of new electronic phenomena in such systems are interference effects, quantum confinement effects and charging effects. Quantum confinement effects describe electrons in terms of energy levels, potential well, valence bands, conduction band, electron energy band gaps. Electrons in bulk dielectric material can be described by energy bands or electron energy levels. Electrons exist at different energy bands. In bulk materials these energy levels are described as continuous because the difference in energy is negligible.

As electrons stabilise at various energy levels, most vibrate in valence bands below a forbidden energy level, named the band gap. This region is an energy range in. A smaller amount have energy levels above the forbidden gap, this is the conduction band; the quantum confinement effect can be observed once the diameter of the particle is of the same magnitude as the wavelength of the electron's wave function. When materials are this small, their electronic and optical properties deviate from those of bulk materials; as the material is miniaturized towards nano-scale the confining dimension decreases. But the characteristics are no longer averaged by bulk, hence continuous, but are at the level of quanta and thus discrete. In other words, the energy spectrum becomes discrete, measured as quanta, rather than continuous as in bulk materials; as a result, the bandgap asserts itself: there is a small and finite separation between energy levels. This situation of discrete energy levels is called quantum confinement.

In addition, quantum confinement effects consist of isolated islands of electrons that may be formed at the patterned interface between two different semiconducting materials. The electrons are confined to disk-shaped regions termed quantum dots; the confinement of the electrons in these systems changes their interaction with electromagnetic radiation as noted above. Because the electron energy levels of quantum dots are discrete rather than continuous, the addition or subtraction of just a few atoms to the quantum dot has the effect of altering the boundaries of the bandgap. Changing the geometry of the surface of the quantum dot changes the bandgap energy, owing again to the small size of the dot, the effects of quantum confinement. In the mesoscopic regime, scattering from defects – such as impurities – induces interference effects which modulate the flow of electrons; the experimental signature of mesoscopic interference effects is the appearance of reproducible fluctuations in physical quantities.

For example, the conductance of a given specimen oscillates in an random manner as a function of fluctuations in experimental parameters. However, the same pattern may be retraced if the experimental parameters are cycled back to their original values; these are known as universal conductance fluctuations. Time-resolved experiments in mesoscopic dynamics: the observation and study, at nanoscales, of condensed ph

James Mworia

James Mwirigi Mworia is a Kenyan lawyer and business executive. He is the managing director and chief executive officer of Centum Investment Company, the largest publicly traded private capital firm in Eastern Africa, he has served in that capacity since 2008. Mworia was born in 1978, he attended Alliance High School, Strathmore University, the University of Nairobi. He has a Bachelor of Laws from Nairobi University, he is a certified public accountant and a chartered financial analyst. In 2016, Machakos University awarded him an honorary doctorate degree. In 2001, Mworia began working as a filing clerk at Centum Investment Company. Despite having a law degree and several other financial and accounting diplomas and certificates, he accepted this entry-level position, he rose through the ranks, in 2005 he was appointed chief investment officer at Centum Investments. He served in that position until December 2006, when he joined TransCentury Investments as its head of investments. In 2008, at age 30, he was appointed chief managing director at Centum.

During his first six years as CEO, Centum increased its asset base from KES:6 billion to KES:30 billion. He serves as the chairman of the board of directors at Sidian Bank, he serves as a board member at the Nairobi Stock Exchange, effective June 2015. In June 2018, he is expected to leave the board of the NSE, having served his three year term, having declined to offer himself for re-election. In September 2016, he was named the highest paid executive among the five largest corporations in Kenya, with an annual compensation package valued at KES:201.1 million annually. In October 2016, he was appointed Chancellor of Machakos University, a public university in Machakos County, Kenya. According to a 2011 published report, James Mworia is a married father. Nairobi Securities Exchange Uganda Securities Exchange Tutu's Children - James Mworia:'Being World Class'

Fran├žoise Aron Ulam

Françoise Aron Ulam was the wife of Polish-American mathematician, Stanislaw Ulam. Born March 8, 1918, in Paris, the daughter of Daniel Pierre Aron and Madeleine. In 1939, she came to the United States as an exchange student, she studied at Mills College and Mount Holyoke College, earning a Master's degree in Comparative Literature. In 1941 she met Stanislaw Ulam. In 1943, the Ulams moved from Los Alamos to Santa Fe following Stanislaw's involvement in the Manhattan Project in Los Alamos at its inception. In Los Alamos, Francoise became part of the international community of scientists and mathematicians during the Atomic Age. Like many of the Manhattan Project wives she knew little about the purpose of the "Gadget," as the bomb was known at the time, she devoted herself to creating a home and raising a baby in the American Southwest, developing a taste for computers and feldenkrais. In 1984, when her husband died, Françoise arranged for Santa Fe Institute to receive Stanislaw Ulam's library. On April 30, 2011, Françoise died at El Castillo, aged 93.

Françoise was buried in Paris. Ulam, Françoise. Analogies Between Analogies: The Mathematical Reports of S. M. Ulam and his Los Alamos Collaborators. 1990. ISBN 978-0520052901 Ulam, Françoise. De Paris a Los Alamos, Une odyssée franco-americaine. ISBN 978-2738459626 Ulam, Stanislaw. Adventures of a Mathematician. 1976. ISBN 978-0520071544

Spirit (Earth, Wind & Fire album)

Spirit is the seventh studio album by Earth, Wind & Fire, released in September 1976 by Columbia Records. The album rose to No. 2 on both Top Soul Albums charts. Spirit has been certified Double Platinum in the US by the RIAA; as Charles Stepney died in the midst of its recording sessions, Maurice White went on to arrange and produce the album. The LP was thus entitled Spirit in dedication to Stepney. Billboard magazine in its review found that the album's "arrangements, sweet floating vocal harmonies and punching instrumental phrases are all best described as impeccable". Vibe called the album "one of the group's defining moments" and "soul for the ages"; the New York Times described Spirit as an LP which crosses "any stylistic formats" of music. Spirit was nominated for an American Music Award for Favorite B Album; the album cut Earth and Fire was Grammy nominated for Best Instrumental Composition. "Getaway" reached No. 1 on the Billboard Hot Soul Songs chart. The single rose to No. 12 on both the Billboard Hot 100 and Disco Action Top 30 charts.

"Saturday Nite, peaked at No. 4 on the Billboard Hot Soul Songs chart and No. 21 on the Billboard Hot 100 chart. The song reached No. 12 on Billboard's Disco Action Top 30 chart and No. 17 on the UK Singles chart. Credits are adapted from the album’s text. Vocals - Maurice White, Philip Bailey, Verdine White Piano, Keyboards - Larry Dunn, Jerry Peters Organ - Larry Dunn Moog synthesizer - Larry Dunn Guitar - Al McKay, Johnny Graham Bass - Verdine White Congas - Philip Bailey Kalimba - Maurice White Timbales - Maurice White Drums - Fred White, Ralph Johnson, Maurice White Percussion - Fred White, Ralph Johnson, Al McKay, Andrew Woolfolk, Verdine White, Philip Bailey, Harvey Mason Saxophone - Don Myrick, Andrew Woolfolk Trombone - George Bohanon, Louis Satterfield, Charles Loper Bass Trombone - Lew McCreary Trumpet - Oscar Brashear, Charles Findley, Michael Harris, Steve Madaio French horn - David Duke, Arthur Maebe, Sidney Muldrow, Marilyn Robinson Tuba - Tommy Johnson Concertmaster - Charles Veal Harp - Dorothy Ashby Cello - Ronald Cooper, Marie Fera, Dennis Karmazyn, Harry Shlutz Viola - Marilyn Baker, David Campbell, Denyse Buffum, Rollice Dale, James Dunham, Paul Polivnick, Lynn Subotnick, Barbara Thomason Violin - Asa Drori, Winterton Garvey, Harris Goldman, Carl LaMagna, Joy Lyle, Sandy Seemore, Haim Shtrum, Ken Yerke Producers - Maurice White, Charles Stepney, Leo Sacks Arrangers - Jerry Peters, Charles Stepney, Tom Tom 84 Engineer, Remix - George Massenburg Audio Mixing - Paul Klingberg, Leo Sacks, Maurice White

Rohrbach Romar

The Rohrbach Ro X Romar was a German long-range commercial flying-boat and the last aircraft designed and built by Rohrbach Metall Flugzeugbau GmbH. The Romar was the final production aircraft from Rohrbach and was a monoplane flying-boat with a crew of four or five and two cabins for a total of 12 passengers; the revised Romar II could accommodate 16 passengers. It had three BMW VIUZ Vee piston engines strut mounted above the wing; the first aircraft flew on 7 August 1928 and was unveiled at the Berlin Aviation Exhibition in October 1928. Only four aircraft were built, three were used on Baltic services by Deutsche Luft Hansa and one was supplied to the French Navy. FranceFrench Navy Weimar RepublicDeutsche Luft Hansa Data from Jane's all the World's Aircraft 1928General characteristics Crew: 4 Capacity: 12 pax Length: 22 m Wingspan: 36.9 m Height: 8.3 m Wing area: 170 m2 Empty weight: 9,900 kg Gross weight: 19,000 kg Powerplant: 3 × BMW VI UZ V-12 water-cooled piston engines, 370 kW each -540 kW Propellers: 4-bladed fixed pitch pusher propellersPerformance Maximum speed: 217 km/h at 14,900 kg.

Jane's Encyclopedia of Aviation. London: Studio Editions; the Illustrated Encyclopedia of Aircraft. Orbis Publishing. Rohrbach X "Romar"

The Pest (1997 film)

The Pest is a 1997 American comedy film inspired by the classic short story "The Most Dangerous Game". Comedian John Leguizamo plays a Puerto Rican con artist in Miami, Florida named Pestario Rivera Garcia Picante Salsa Vargas who agrees to be the human target for a German manhunter for a US$50,000 reward. Puerto Rican teenage con artist Pestario “Pest” Vargas owes $50,000 U. S. dollars to the Scottish mob, led by Angus, eager to exact revenge against Pest so that the Scottish mob will be feared. Pest, along with his friends Ninja and Chubby, perform a scam at a festival. While there, Pest promises his girlfriend Xantha Kent he will have dinner with her parents. Racist German hunter Gustav Shank, who desires to hunt the warriors of different nationalities, decides to hunt an athlete, his servant mistakenly believes Shank has decided to hunt Pest and brings Pest to Shank, who decides to hunt Pest anyway due to how irritating he is. Shank tricks Pest into allowing himself to be hunted, but despite the warnings from Shank's weirdly effeminate son Himmel in regards to what has gotten himself into, Pest decides to participate anyway, since he will get a $50,000 reward if he survives.

As Pest is brought to Shank's private island, Pest is supplied with a tiny gun and runs off into the jungle. Pest convinces Himmel to get him off the island, both escape in Shank's boat. Himmel and Pest are attacked by seagulls, Pest swims to shore, meeting up with Chubby and Ninja at a pool party. Shank arrives in a helicopter and Pest and Ninja flee. Pest goes to Xantha's house for the dinner, only for a tracking device Shank has attached to him to explode. Shank arrives and goes after Pest, only to inadvertently tranquilize Xantha's father and Ninja. Pest and Chubby hide in a nightclub. Shank once again attacks Pest, only for Pest to cover Shank in a pheromone that results in him being swarmed by horny men. Pest and Chubby reunite with Ninja, only for them to be shoved into a car with Angus, who Shank has convinced Pest is trying to skip town. Shank reveals he has kidnapped Pest's family and Xantha and her family, has them on board a large boat. Pest and Chubby outwit Shank and free the captives.

Shank reveals he had poisoned a drink Pest had drunk, tells Pest how to find his reward to taunt him. The next day, Shank discovers his money has been stolen by Pest, who had vomited the poison out due to getting seasick while escaping the island. Pest has revealed Shank's crimes to the authorities. Shank is dragged away by several police officers, while Pest, Chubby and Xantha drive off with Shank's money. John Leguizamo as Pestario'Pest' Vargas Jeffrey Jones as Gustav Shank Edoardo Ballerini as Himmel Shank Freddy Rodríguez as Bruce "Ninja" Tammy Townsend as Xantha Kent Aries Spears as Chubby Charles Hallahan as Angus Tom McCleister as Leo Joe Morton as Mr. Kent Ivonne Coll as Gladyz Pat Skipper as Glen Livitt The film was a box office bomb. Jeff Millar of the Houston Chronicle wrote that "This film is utterly without discipline or focus in a way that—to one's shame—one finds oddly endearing". Dwayne E. Leslie of Boxoffice magazine said that "The script and Leguizamo's talents don't mesh, so the actor comes off as more offensive than funny."

Bill Hoffman of The New York Post gave the comedy half out of five stars. Mick LaSalle of San Francisco Chronicle said of Leguizamo's performance "Obviously, someone must have told Leguizamo he's a comic genius. Whoever did that wasn't a good friend." Ken Fox of TV Guide gave the film 1.5 out of 4, wrote: "Even surrounded by unbearable sloppiness, Leguizamo is fascinating to watch."The film holds an 8% approval rating on Rotten Tomatoes based on 24 reviews, with an average rating of 2.3/10. Leguizamo was nominated for Worst Actor for his performance in the film at the 1997 Stinkers Bad Movie Awards but lost to Tom Arnold for McHale's Navy; the film grossed $3.5 million on an estimated budget of $17 million. Director Paul Miller provided an audio commentary track for the film's 2001 DVD release; the film was rated PG-13 for sexual and ethnic humor. The Pest on IMDb The Pest at AllMovie The Pest at Rotten Tomatoes The Pest at Box Office Mojo