In fluid dynamics, a vortex is a region in a fluid in which the flow revolves around an axis line, which may be straight or curved. Vortices form in stirred fluids, may be observed in smoke rings, whirlpools in the wake of a boat, the winds surrounding a tropical cyclone, tornado or dust devil. Vortices are a major component of turbulent flow; the distribution of velocity, vorticity, as well as the concept of circulation are used to characterize vortices. In most vortices, the fluid flow velocity is greatest next to its axis and decreases in inverse proportion to the distance from the axis. In the absence of external forces, viscous friction within the fluid tends to organize the flow into a collection of irrotational vortices superimposed to larger-scale flows, including larger-scale vortices. Once formed, vortices can move, stretch and interact in complex ways. A moving vortex carries with it some angular and linear momentum and mass. A key concept in the dynamics of vortices is the vorticity, a vector that describes the local rotary motion at a point in the fluid, as would be perceived by an observer that moves along with it.

Conceptually, the vorticity could be observed by placing a tiny rough ball at the point in question, free to move with the fluid, observing how it rotates about its center. The direction of the vorticity vector is defined to be the direction of the axis of rotation of this imaginary ball while its length is twice the ball's angular velocity. Mathematically, the vorticity is defined as the curl of the velocity field of the fluid denoted by ω → and expressed by the vector analysis formula ∇ × u →, where ∇ is the nabla operator and u → is the local flow velocity; the local rotation measured by the vorticity ω → must not be confused with the angular velocity vector of that portion of the fluid with respect to the external environment or to any fixed axis. In a vortex, in particular, ω → may be opposite to the mean angular velocity vector of the fluid relative to the vortex's axis. In theory, the speed u of the particles in a vortex may vary with the distance r from the axis in many ways. There are two important special cases, however: If the fluid rotates like a rigid body – that is, if the angular rotational velocity Ω is uniform, so that u increases proportionally to the distance r from the axis – a tiny ball carried by the flow would rotate about its center as if it were part of that rigid body.

In such a flow, the vorticity is the same everywhere: its direction is parallel to the rotation axis, its magnitude is equal to twice the uniform angular velocity Ω of the fluid around the center of rotation. Ω → =, r → =, u → = Ω → × r → =, ω → = ∇ × u → = = 2 Ω →. If the particle speed u is inversely proportional to the distance r from the axis the imaginary test ball would not rotate over itself. In this case the vorticity ω → is zero at any point not on that axis, the flow is said to be irrotational. Ω → =, r → =, u → = Ω → × r → =, ω → = ∇ × u → = 0. In the absence of external forces, a vortex evolves quickly toward the irrotational flow pattern, where the flow velocity u is inversely proportional to the distance r. Irrotational vortices are called free vortices. For an irrotational vortex, the circulation is zero along any closed contour that does not enclose

Filippo Baldi Rossi is an Italian professional basketball player for Virtus Bologna of the Italian Lega Basket Serie A. Standing at 2.07 m, he plays at center positions. Filippo Baldi Rossi began to play with the senior team of Virtus Bologna at the age 17. During the 2010-11 and 2011-12 he played on loan to Perugia Basket. In 2012 he went to Auxilium Torino. In 2013 he signed a contract with Aquila Basket Trento in Serie A2 Basket, he still plays in the Trento's major basketball club in the Italian LBA. In February 3, 2016, during a match of the Last 32 round in EuroCup against Pallacanestro Reggiana, he was injured on the left knee. and he had to undergo an operation on the front crusader. For that reason he blasted the rest of the season. A long rehabilitation took at the Isokinetic Centre in Bologna, where he got a full recovery after the operation. In November 30, 2017, Baldi Rossi signed a deal with Segafredo Virtus Bologna, his contract will run through 2019. Baldi Rossi played the 2011 FIBA Europe Under-20 Championship in 2011 with the Italy national under-20 basketball team, where he won the Silver medal.

In 2017 Filippo Baldi Rossi entered into the sperimental Italian Senior Basketball Team. He was in the 12s of coach Ettore Messina for EuroBasket 2017 in Israel and Turkey, because of Davide Pascolo who missed EuroBasket with a right knee injury. Filippo Baldi Rossi at legabasket.it Filippo Baldi Rossi at fiba.com Filippo Baldi Rossi at eurobasket.com Filippo Baldi Rossi at eurocupbasketball.com

The chapel of Notre-Dame-de-Jérusalem is a Catholic chapel of the Diocese of Fréjus-Toulon. The chapel is the last work of French poet Jean Cocteau. In 1957, Cocteau finished the decorated the 16th-century Romanesque chapel of Saint Peter in the Villefranche-sur-Mer chapel. At the origin of the chapel is Louis Martinon, a banker from Nice who wanted a private chapel for the inhabitants of the Tour de Mare district of Fréjus, a 1,200-hectare housing estate that he imagined as an "ideal city" to house a population of artists. In 1962, Martinon commissioned Jean Cocteau to design the plans and the decoration of the chapel. Cocteau was assisted by the architect Jean Triquenot, painter Raymond Moretti and ceramist Roger Pelissier; the foundation stone was laid on 24 February 1963 but the unexpected death of the poet on 11 October 1963 interrupted the work. Cocteau's adopted son Édouard Dermit transferred on the cement walls the 150 sketches left by Cocteau and realized the frescoes with the help of charcoal and oil color pencils.

Inspired by the Torcello Cathedral and the Pantheon, Triquenot designed an octagonal chapel with large walls to accommodate the frescoes and an oculus. From the entrance door, the frescoes of the chapel revolve around the theme of the Passion of Jesus Christ. At the Last Supper, Cocteau gave the 12 apostles his face, the face of his close relatives: Jean Marais, Coco Chanel, Max Jacob, Édouard Dermit and Francine Weisweiller. Knights of the Order of the Holy Sepulchre are represented on the stained glass of the entrance door and above it. Cocteau reinterpreted the coat of arms of the Order. A farandole symbolizing the resurrection surrounds the oculus of the rotunda; the stained glass windows and the floor covered with blue ceramics, evoking the Mediterranean Sea, are the creation of Roger Pélissier. The floor is decorated with a Jerusalem cross and the motto of the Crusaders: "Dieu le veut"; the ambulatory is decorated with 6 mosaics made in 1992 from Cocteau's drawings, with the tiles made of pâte de verre from Murano.

A red Jerusalem cross, whose 5 wings symbolize the 5 wounds of Christ, is placed on the top of the chapel roof. The chapel has been listed on the supplementary inventory of historical monuments since 20 January 1989, it became a museum after its restoration short after. Chapelle Notre-Dame de Jérusalem, dite chapelle Cocteau on the site Patrimages.culture.gouv.fr Grand sud insolite: La chapelle Notre-Dame de Jérusalem ou chapelle Cocteau, with vidéo Chapelle Notre-Dame-de-Jérusalem, dite aussi Chapelle Cocteau, on Monumentum

Mongol Post JSC is the national postal service of Mongolia. The state-owned Mongol Post was transformed to joint stock company on April 11, 2016 by offering 34 percent of the total shares to the public, it was founded by the Mongolian People's Republic in 1935 and went under several different names before its current structure was established in 1994. The Mongol Post JSC is charge of postal services and issuing of postage stamps; the headquarters are in Ulaanbaatar, the company employs over 900 people and has over 389 post offices. The company is charged with providing the following postal and communication services at the pot offices. Basic postal services Additional postal services International postal services Express Mail Services Postal InsuranceOf Mongolia's 3 million inhabitants, 30% are nomadic, 61% of Ulaanbaatar's population live in informal settlements; this population had "no consistent addressing system" until May 2016 when Mongol Post started using a geocoding system provided by what3words.

The modern postal system of Mongolia started with the establishment of a state committee for post and telegraph by the Mongolian People's Republic. From 1935 the postal system had a succession of names commencing as the'City Post Committee', including'Central Post','Telegraph and Communication Office', until 2002 when renamed Mongol Post. The'Mongol Post Bank', a private bank that operated from 1994 to 2009, was never related to the'Mongol Post' organisation. Postage stamps and postal history of Mongolia Mongol Shuudan, a rock band from Russia named after the Mongol Post Mongolian postal address format by UPU

The Centre for Advanced Spatial Analysis is a research centre at University College London, which specialises in the application and visualisation of spatial analytic techniques and simulation models to cities and regions. It is a constituent department of The Bartlett Faculty of the Built-Environment. CASA was established in 1995 by a group of UCL academics who wanted a focus for their research across different academic departments in the field of geographic information systems. Michael Batty was appointed the first director and held a joint appointment as Professor of Spatial Analysis and Planning in the Departments of Geography and The Bartlett School of Planning, he is now Chairman of the Centre. In 2000, Paul Longley was appointed Deputy Professor of Geographic Information Science, he now directs UCL's ESRC Consumer Data Research Centre. CASA is still funded through research grants but from 2010 it began to diversify, introducing Masters programmes in spatial analysis and in Smart Cities.

Professor Andrew Hudson-Smith took over the directorship in 2011 and appointed a Deputy Director, Dr Adam Dennett in 2016. Adam Dennett is now the Director of the Associate Professor. Masters courses developed since 2010 include MSc's in Smart Cities and Urban Analytics and Spatial Data Science and Visualisation, it has 10 lecturers/associate Professors and two teaching fellows leading its courses. Sir Alan Wilson was appointed Professor of Urban and Regional Systems in 2008 but moved to the Turing Institute in 2016; the Centre is now an administrative unit in The Bartlett School, the Faculty of the Built Environment. CASA researches the science of cities, working with city governments and related research groups on simulating and visualising urban problems, their work on transport and movement has included Transport for London’s Oyster card data, public bikes schemes such as the London's cycle hire scheme, population segregation in large cities as well as climate change in the London region.

The centre is active in exploring how the Internet of Things can be deployed in large urban areas linking objects in the built environment through internet technologies, was active with the Technology Strategy Board’s Future Cities Catapult in pioneering new software systems for smart cities such as dashboards and portals. Its research programme in city science concentrates on applying social physics to urban systems based on modelling the diffusion of behaviours such as the 2011 London riots and it is involved in using methods of scaling and allometry to examine city performance. CASA’s research programme is funded by research grants from the British research councils ESRC and EPSRC. Since 2008, the centre has been funded by EU research grants from the 7th Framework and from the European Research Council and in 2014, it was awarded funding from the Technology Strategy Board's Future Cities Catapult to provide demonstration capabilities for urban and regional modelling. CASA has graduated some 50 PhDs since 2000.

Several alumni have made important contributions to the science of cities working in geographic information systems, spatial analysis and urban modelling at UC Berkeley, Maryland, NYU, George Mason, UCL, KRISH, LSE, TU-Istanbul, KCL, Tehran, Manchester, OU, ETH-Zurich, Malta, Warwick and Liverpool. OpenStreetMap originated in UCL CASA and The Bartlett, the firms GeoFutures and Intelligent Space were associated with the centre; the company Prospective Labs spun-off from CASA in 2016 and is engaged on developing new software systems for planning and land management. Members of CASA have pioneered the development of urban and regional modelling through a series of books that go back to the 1970s, their work is published in a series of web sites on the CASA Blog Aggregator. Key works that reflect CASA’s research programme are Fractal Cities and Complexity, The Science of Cities and Regions, Agent Based Model of Geographical Systems, The New Science of Cities; the journals Environment and Planning B, edited by Batty, Future Internet, edited by Hudson-Smith, are run from CASA.

The major research focus of CASA is in blending the visualisation of complex urban systems with their simulation. CASA website CASA Blog Aggregator

The Madonna and Child with Two Musician Angels is an oil on panel painting by Correggio, now in the Uffizi in Florence. Some date it to 1514-15 but it is more dated to 1515-16. On the back of the painting is a 16th-century monogram from the grand-ducal gallery in Florence, showing the identification number 2523, which does not feature in any of the lists of the gallery's holdings at that time. Though it cannot be traced in any 17th-century inventories, it was one of the works taken to Düsseldorf by Anna Maria Luisa de' Medici in 1691 on her marriage to John William, Elector Palatine and which were brought back to Florence; the first official mention places the work in the inventory of the Gallerie fiorentine in 1798, in the Sala dei Maestri Italiani, where it remained until the mid-19th century. Many copies were commissioned from the 18th century onwards, it was attributed to Titian, but Giovanni Morelli reattributed it as an early work by a young Correggio - this became the dominant attribution, supported by "the minute technical execution and the clear and shining colours".

Giuseppe Adani, Correggio pittore universale, Silvana Editoriale, Correggio 2007. ISBN 9788836609772 "La scheda ufficiale di catalogo". "Scheda della Fondazione Correggio"