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In Euclidean plane geometry, a quadrilateral is a polygon with four edges and four vertices or corners. Sometimes, the term quadrangle is used, by analogy with triangle, sometimes tetragon for consistency with pentagon, hexagon and so on; the word "quadrilateral" is derived from the Latin words quadri, a variant of four, latus, meaning "side". Quadrilaterals are simple or complex called crossed. Simple quadrilaterals are either concave; the interior angles of a simple quadrilateral ABCD add up to 360 degrees of arc, ∠ A + ∠ B + ∠ C + ∠ D = 360 ∘. This is a special case of the n-gon interior angle sum formula × 180°. All non-self-crossing quadrilaterals tile the plane by repeated rotation around the midpoints of their edges. Any quadrilateral, not self-intersecting is a simple quadrilateral. In a convex quadrilateral, all interior angles are less than 180° and the two diagonals both lie inside the quadrilateral. Irregular quadrilateral or trapezium: no sides are parallel. Trapezium or trapezoid: at least one pair of opposite sides are parallel.

Trapezia and trapezoids include parallelograms. Isosceles trapezium or isosceles trapezoid: one pair of opposite sides are parallel and the base angles are equal in measure. Alternative definitions are a quadrilateral with an axis of symmetry bisecting one pair of opposite sides, or a trapezoid with diagonals of equal length. Parallelogram: a quadrilateral with two pairs of parallel sides. Equivalent conditions are. Parallelograms include rhomboids. In other words, parallelograms include all rhombi and all rhomboids, thus include all rectangles. Rhombus or rhomb: all four sides are of equal length. An equivalent condition is. Informally: "a pushed-over square". Rhomboid: a parallelogram in which adjacent sides are of unequal lengths and some angles are oblique. Informally: "a pushed-over oblong". Not all references agree, some define a rhomboid as a parallelogram, not a rhombus. Rectangle: all four angles are right angles. An equivalent condition is that the diagonals are equal in length. Rectangles include oblongs.

Informally: "a box or oblong". Square: all four sides are of equal length, all four angles are right angles. An equivalent condition is that opposite sides are parallel, that the diagonals perpendicularly bisect each other, are of equal length. A quadrilateral is only if it is both a rhombus and a rectangle. Oblong: a term sometimes used to denote a rectangle that has unequal adjacent sides. Kite: two pairs of adjacent sides are of equal length; this implies that one diagonal divides the kite into congruent triangles, so the angles between the two pairs of equal sides are equal in measure. It implies that the diagonals are perpendicular. Kites include rhombi. Tangential quadrilateral: the four sides are tangents to an inscribed circle. A convex quadrilateral is only if opposite sides have equal sums. Tangential trapezoid: a trapezoid where the four sides are tangents to an inscribed circle. Cyclic quadrilateral: the four vertices lie on a circumscribed circle. A convex quadrilateral is cyclic if and only if opposite angles sum to 180°.

Right kite: a kite with two opposite right angles. It is a type of cyclic quadrilateral. Harmonic quadrilateral: the products of the lengths of the opposing sides are equal, it is a type of cyclic quadrilateral. Bicentric quadrilateral: it is both tangential and cyclic. Orthodiagonal quadrilateral: the diagonals cross at right angles. Equidiagonal quadrilateral: the diagonals are of equal length. Ex-tangential quadrilateral: the four extensions of the sides are tangent to an excircle. An equilic quadrilateral has two opposite equal sides that, when extended, meet at 60°. A Watt quadrilateral is a quadrilateral with a pair of opposite sides of equal length. A quadric quadrilateral is a convex quadrilateral whose four vertices all lie on the perimeter of a square. A diametric quadrilateral is a cyclic quadrilateral having one of its sides as a diameter of the circumcircle. A Hjelmslev quadrilateral is a quadrilateral with two right angles at opposite vertices. In a concave quadrilateral, one interior angle is bigger than 180° and one of the two diagonals lies outside the quadrilateral.

A dart is a concave quadrilateral with bilateral symmetry like a kite, but one interior angle is reflex. See kite. A self-intersecting quadrilateral is called variously a cross-quadrilateral, crossed quadrilateral, butterfly quadrilateral or bow-tie quadrilateral. In a crossed quadrilateral, the four "interior" angles on either side of the crossing add up to 720°. Crossed trapezoid or trapezium: a crossed quadrilateral in which one pair of nonadjacent sides is parallel Antiparallelogram: a crossed

Kjell-Åke Andersson

Kjell-Åke Gunnar Andersson is a Swedish film director and cinematographer. His 1992 film Night of the Orangutan was nominated for Best Film, Best Director and Best Screenplay at the 28th Guldbagge Awards. 1980 - Vi hade i alla fall tur med vädret 1988 - Friends 1992 - Night of the Orangutan 1996 - Juloratoriet 2001 - Familjehemligheter 2002 - Stackars Tom 2003 - Mamma pappa barn 2005 - Wallander – Innan frosten 2008 - Vi hade i alla fall tur med vädret – igen Kjell-Åke Andersson at the Swedish Film Database Kjell-Åke Andersson on IMDb

Thomas Whitfield (entrepreneur)

Thomas Whitfield is a British/German biochemist and entrepreneur. He is known for his work on Thomas Whitfield was born in Scotland, he spent his childhood and early schooling in Germany. He holds a DPhil in Biochemistry from University of Oxford. Being an Idea Idol of University of Oxford, he was selected as one of the 2009 Flying Start Global Entrepreneurs by the National Council for Graduate Entrepreneurship of Department for Business and Skills, UK. In 2009 he was selected as a Kauffman Foundation Global Scholar, he was a co-founder and director of") which plots user-generated personal histories. The website attracted vast media attention throughout Europe and was ranked as one of the Top 10 UK Web 2.0 startups in 2007 with co-operation agreements including Microsoft, Wikipedia and the British Library. Despite its popularity the website went offline in 2008 for unknown reasons. In 2009 Whitfield founded the company Oxford Biolabs. In 2011 its first product TRX2, a dietary supplement became publicly available.

Work of Whitfield has been featured in The Daily Telegraph several times, as well as in The Observer, CNN, New Scientist, Der Spiegel, RTL and Tagesschau In 2007 he has been featured during the Google Zeitgeist Entrepreneur of the Year conference. Oxford BioLabs, Oxford BioLabs Official Website, TRX2 Official Website

Genetic memory (biology)

In biology, memory is present if the state of a biological system depends on its history in addition to present conditions. If this memory is recorded in the genetic material and stably inherited through cell division, it is genetic memory. Somatic memory is limited to the organism and not passed on to subsequent generations. However, its mechanism may involve mitotically stable genetic memory; the term applies for cellular memory, animals' memory, plants' memory, as described in the following paragraphs. All cells in multicellular organisms are derived from a pluripotent zygote and contain the same genetic material. However, they are capable of recording a history of their development within the organism leading to their specialized functions and limitations. Cells employ epigenetic processes that affect DNA-protein interactions to record this cellular memory in the form of mitotically stable changes of the genetic material without a change in the DNA sequence itself; this is achieved via changes of the chromatin structure.

Examples are methylation patterns of the DNA molecule itself and proteins involved in packaging DNA, such as histones. A case of somatic genetic memory is the immunological memory of the adaptive immune response in vertebrates; the immune system is capable of learning to recognize pathogens and keeping a memory of this learning process, the basis of the success of vaccinations. Antibody genes in B and T lymphocytes are assembled from separate gene segments, giving each lymphocyte a unique antibody coding sequence leading to the vast diversity of antibodies in the immune system. If stimulated by an antigen, these antibodies are further fine-tuned via hypermutation. Memory B cells capable of producing these antibodies form the basis for acquired immunological memory; each individual therefore carries a unique genetic memory of its immune system's close encounters with pathogens. As a somatic memory, this is not passed on to the next generation. Plants that undergo vernalization record a genetic memory of winter to gain the competence to flower.

The process involves epigenetically recording the length of cold exposure through chromatin remodeling which leads to mitotically stable changes in gene expression. This releases the inhibition of flowering initiation and allows the plants to bloom with the correct timing at the onset of spring; as a somatic memory, this state is not passed on to subsequent generations but has to be acquired by each individual plant. The process of vernalization was falsely assumed to be a stably inherited genetic memory passed on to subsequent generations by the Russian geneticist Trofim Lysenko. Lysenko's claims of genetic memory and efforts to obtain or fabricate results in proof of it had disastrous effects for Russian genetics in the early 20th century. In genetics, genomic imprinting or other patterns of inheritance that are not determined by DNA sequence alone can form an epigenetic memory, passed on to subsequent generations through meiosis. In contrast, somatic genetic memories are passed on by mitosis and limited to the individual, but are not passed on to the offspring.

Both processes include similar epigenetic mechanisms, e.g. involving histones and methylation patterns. In microbes, genetic memory is present in the form of inversion of specific DNA sequences serving as a switch between alternative patterns of gene expression. In population genetics and evolution, genetic memory represents the recorded history of adaptive changes in a species. Selection of organisms carrying genes coding for the best adapted proteins results in the evolution of species. An example for such a genetic memory is the innate immune response that represents a recording of the history of common microbial and viral pathogens encountered throughout the evolutionary history of the species. In contrast to the somatic memory of the adaptive immune response, the innate immune response is present at birth and does not require the immune system to learn to recognize antigens. In the history of theories of evolution, the proposed genetic memory of an individual's experiences and environmental influences was a central part of Lamarckism to explain the inheritance of evolutionary changes.

In ethology, genetic memory refers the inheritance of instinct in animals. Alan Bullock. "Genetic memory". The Harper Dictionary of Modern Thought. Harper & Row. p. 258

Rob Powell (athlete)

Rob Powell is an American athlete and fitness coach. He has two certified World Fitness Challenge /Guinness World Records and is a 4 time World Fitness/Conditioning Champion. Powell founded The World's Fittest Workout Apps, he retired from competition in 2011. Powell grew up on a ranch in Texas, he graduated from W. H. Ford High School as well as South Plains College and Texas Tech University. There are specific events for Guinness World Records set by Rob Powell. Powell's Guinness World Records consist of the following. October 26–27, 2002, 19:17:38 bettering his own world record by nearly 3 hours. WFC 1, October 25–26, 2003, 18:36:15 WFC 2, October 30–31, 2004, 17:45:03 The World fitness challenge consist of the following activities. 1 Mile Swim 5 Mile Run 5 Mile Hike 250 Pop-Ups 250 Hang Knee Lifts 50 Mile Cycle 10 Mile Row 10 Mile Elliptical 1,500 Crunches 150,000 Pounds LiftedThe World fitness championship for is: 2 Mile Swim 10 Mile Run 10 Mile Hike 500 Pop-Ups 500 Hang Knee Lifts 100 Mile Cycle 20 Mile Row 20 Mile Elliptical 3,000 Crunches 300,000 Pounds Lifted World Fitness Champion official site

Devilled kidneys

Devilled kidneys is a Victorian British breakfast dish consisting of lamb's kidneys cooked in a spiced sauce, referred to as "devilling". It has since become more used as a supper-time dish, is featured in cookbooks and by celebrity chefs; the devilling mixture consists of Worcestershire sauce, butter, cayenne pepper and black pepper, although some recipes can include curry powder in them. Chicken stock can be used in the sauce itself. James Boswell described devilling during the 18th century, although it was not until the 19th and 20th centuries that devilled kidneys grew in popularity as a breakfast dish. During the Edwardian era, the dish was served in gentlemen's clubs, was part of a cuisine which included items such as kedgeree or kippers. In the modern era it has been promoted as a supper dish instead of at breakfast. British celebrity chef Rick Stein created a recipe combining devilled kidneys with wild mushrooms to create an entrée; the dish is included in cookbooks, with versions gracing the covers of books by the Canteen restaurant, as well as books by The Hairy Bikers.

Chef Fergus Henderson described Caroline Conran's version of devilled kidneys as "the best recipe, ever!", Marco Pierre White created devils kidneys for the celebrities in one of his seasons of ITV's Hell's Kitchen. List of lamb dishes Food portal