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Yaboyabo

Yaboyabo is an ancient village in the rural community of Séssène, in the Thies Region of Senegal. Linked to Serer mythology and religion and deemed one of the Serer holy sites, Yaboyabo is one of the oldest villages in Senegal. According to the Serer creation myth, Yaboyabo takes its name from the first human couple created by the supreme being Roog; the narrative went on to state that, the original twins were carried from the Empyrean Heaven by an ark. This is believed to be deposited in the sacred village of Yaboyabo. Although the ark of Yaabo-Yabo is an ancient relic under the guardianship of this Serer village, ritually venerated by those who adhere to the tenets of Serer religion, it is unlikely to be the original "ark" and was an ancient replica. Many Serer homes have ancient artifacts; the population is overrun by the original inhabitants. As of 2012, the population is estimated to be between 1715 and 1953; some of the nearest localities include Tattaguine, Saokom, Sakone and Diarab. The closest major cities include Kaolack.

Gravrand, Henry, "La Civilisation Sereer - Pangool", vol. 2. Les Nouvelles Editions Africaines du Senegal, ISBN 2-7236-1055-1 Becker, Charles, "Vestiges historiques, témoins matériels du passé dans les pays sereer", CNRS-ORSTOM, Dakar, 1993

Exoplanetology

Exoplanetology, or exoplanetary science, is an integrated field of astronomical science dedicated to the search for and study of exoplanets. It employs an interdisciplinary approach which includes astrobiology, astronomy, astrogeology and planetary science; the exoplanet naming convention is an extension of the system used for naming multiple-star systems as adopted by the International Astronomical Union. For an exoplanet orbiting a single star, the name is formed by taking the name of its parent star and adding a lowercase letter; the first planet discovered in a system is given the designation "b" and planets are given subsequent letters. If several planets in the same system are discovered at the same time, the closest one to the star gets the next letter, followed by the other planets in order of orbit size. A provisional IAU-sanctioned standard exists to accommodate the naming of circumbinary planets. A limited number of exoplanets have IAU-sanctioned proper names. Other naming systems exist.

The official definition of "planet" used by the International Astronomical Union only covers the Solar System and thus does not apply to exoplanets. As of April 2011, the only defining statement issued by the IAU that pertains to exoplanets is a working definition issued in 2001 and modified in 2003; that definition contains the following criteria: Objects with true masses below the limiting mass for thermonuclear fusion of deuterium that orbit stars or stellar remnants are "planets". The minimum mass/size required for an extrasolar object to be considered a planet should be the same as that used in the Solar System. Substellar objects with true masses above the limiting mass for thermonuclear fusion of deuterium are "brown dwarfs", no matter how they formed or where they are located. Free-floating objects in young star clusters with masses below the limiting mass for thermonuclear fusion of deuterium are not "planets", but are "sub-brown dwarfs"; the IAU's working definition is not always used.

One alternate suggestion is that planets should be distinguished from brown dwarfs on the basis of formation. It is thought that giant planets form through core accretion, which may sometimes produce planets with masses above the deuterium fusion threshold. Brown dwarfs form like stars from the direct gravitational collapse of clouds of gas and this formation mechanism produces objects that are below the 13 MJup limit and can be as low as 1 MJup. Objects in this mass range that orbit their stars with wide separations of hundreds or thousands of AU and have large star/object mass ratios formed as brown dwarfs. Most directly imaged planets as of April 2014 are massive and have wide orbits so represent the low-mass end of brown dwarf formation. One study suggests that objects above 10 MJup formed through gravitational instability and should not be thought of as planets; the 13-Jupiter-mass cutoff does not have precise physical significance. Deuterium fusion can occur in some objects with a mass below that cutoff.

The amount of deuterium fused depends to some extent on the composition of the object. As of 2011 the Extrasolar Planets Encyclopaedia included objects up to 25 Jupiter masses, saying, "The fact that there is no special feature around 13 MJup in the observed mass spectrum reinforces the choice to forget this mass limit"; as of 2016 this limit was increased to 60 Jupiter masses based on a study of mass–density relationships. The Exoplanet Data Explorer includes objects up to 24 Jupiter masses with the advisory: "The 13 Jupiter-mass distinction by the IAU Working Group is physically unmotivated for planets with rocky cores, observationally problematic due to the sin i ambiguity." The NASA Exoplanet Archive includes objects with less than 30 Jupiter masses. Another criterion for separating planets and brown dwarfs, rather than deuterium fusion, formation process or location, is whether the core pressure is dominated by coulomb pressure or electron degeneracy pressure with the dividing line at around 5 Jupiter masses.

Planets are faint compared with their parent stars. For example, a Sun-like star is about a billion times brighter than the reflected light from any exoplanet orbiting it, it is difficult to detect such a faint light source, furthermore the parent star causes a glare that tends to wash it out. It is necessary to block the light from the parent star in order to reduce the glare while leaving the light from the planet detectable. All exoplanets that have been directly imaged are both large and separated from their parent star. Specially designed direct-imaging instruments such as Gemini Planet Imager, VLT-SPHERE, SCExAO will image dozens of gas giants, but the vast majority of known extrasolar planets have only been detected through indirect methods; the following are the indirect methods that have proven useful: Transit methodIf a planet crosses in front of its parent star's disk the observed brightness of the star drops by a small amount. The amount by which the star dims depends on its size and on the size of the planet, among other factors.

Because the transit method requires that the planet's orbit intersect a line-of-sight between the host star

SNX1

Sorting nexin-1 is a protein that in humans is encoded by the SNX1 gene. The protein encoded by this gene is a sorting nexin. SNX1 is a component of the retromer complex; this gene encodes a member of the sorting nexin family. Members of this family contain a phox domain, a phosphoinositide binding domain, are involved in intracellular trafficking; this endosomal protein regulates the cell-surface expression of epidermal growth factor receptor. This protein has a role in sorting protease-activated receptor-1 from early endosomes to lysosomes; this protein may form oligomeric complexes with other family members. Sorting+nexins at the US National Library of Medicine Medical Subject Headings This article incorporates text from the United States National Library of Medicine, in the public domain

National Register of Historic Places listings in Hidalgo County, Texas

This is a list of the National Register of Historic Places listings in Hidalgo County, Texas This is intended to be a complete list of properties and districts listed on the National Register of Historic Places in Hidalgo County, Texas. There are 18 individual properties listed on the National Register in the county. One property is a State Antiquities Landmark. Seven properties are designated Recorded Texas Historic Landmarks while two districts and two more individual properties contain RTHLs within their boundaries; this National Park Service list is complete through NPS recent listings posted February 28, 2020. The locations of National Register properties and districts may be seen in a mapping service provided. National Register of Historic Places listings in Texas Recorded Texas Historic Landmarks in Hidalgo County Media related to National Register of Historic Places in Hidalgo County, Texas at Wikimedia Commons

Gonioreflectometer

A gonioreflectometer is a device for measuring a bidirectional reflectance distribution function. The device consists of a light source illuminating the material to be measured and a sensor that captures light reflected from that material; the light source should be able to illuminate and the sensor should be able to capture data from a hemisphere around the target. The hemispherical rotation dimensions of the sensor and light source are the four dimensions of the BRDF. The'gonio' part of the word refers to the device's ability to measure at different angles. Several similar devices have been used to capture data for similar functions. Most of these devices use a camera instead of the light intensity-measuring sensor to capture a two-dimensional sample of the target. Examples include: a spatial gonioreflectometer for capturing the SBRDF. A camera gantry for capturing the light field. An unnamed device for capturing the bidirectional texture function. Dana, Kristin et al. 1999. Reflectance and Texture of Real-World Surfaces. in ACM Transactions on Graphics.

Volume 18, Issue 1. New York, NY, USA: ACM Press. Pages 1-34. Foo, Sing Choong. 1997. A Gonioreflectometer for measuring the bidirectional reflectance of materials for use in illumination computations. Masters thesis. Cornell University. Ithaca, New York, USA. Levoy, Marc & Hanrahan, Pat. 1996. Light field rendering. In Proceedings of the 23rd annual conference on Computer graphics and interactive techniques. McAllister, David. 2002. A Generalized Surface Appearance Representation for Computer Graphics. PhD dissertation. University of North Carolina at Chapel Hill, Department of Computer Science. Chapel Hill, USA. 118p