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Topic Review
Triceratops
Triceratops (/traɪˈsɛrəˌtɒps/ trahy-ser-uh-tops; lit. three-horned face) is a genus of herbivorous chasmosaurine ceratopsid dinosaur that first appeared during the late Maastrichtian stage of the Late Cretaceous period, about 68 million years ago in what is now North America. It is one of the last-known non-avian dinosaur genera, and became extinct in the Cretaceous–Paleogene extinction event 66 million years ago. The name Triceratops, which literally means 'three-horned face', is derived from the Greek words trí- (τρί-) meaning 'three', kéras (κέρας) meaning 'horn', and ṓps (ὤψ) meaning 'face'. Bearing a large bony frill, three horns on the skull, and a large four-legged body, exhibiting convergent evolution with rhinoceroses and bovines, Triceratops is one of the most recognizable of all dinosaurs and the most well-known ceratopsid. It was also one of the largest, up to 8–9 metres (26–30 ft) long and 5–9 metric tons (5.5–9.9 short tons) in body mass. It shared the landscape with and was most likely preyed upon by Tyrannosaurus, though it is less certain that two adults did battle in the fanciful manner often depicted in museum displays and popular images. The functions of the frills and three distinctive facial horns on its head have long inspired debate. Traditionally, these have been viewed as defensive weapons against predators. More recent interpretations find it probable that these features were primarily used in species identification, courtship, and dominance display, much like the antlers and horns of modern ungulates. Triceratops was traditionally placed within the "short-frilled" ceratopsids, but modern cladistic studies show it to be a member of the Chasmosaurinae which usually have long frills. Two species, T. horridus and T. prorsus, are considered valid today, from the seventeen species that have ever been named. Research published in 2010 concluded that the contemporaneous Torosaurus, a ceratopsid long regarded as a separate genus, represents Triceratops in its mature form. This view has been disputed; further data is needed to settle the debate. Triceratops has been documented by numerous remains collected since the genus was first described in 1889 by American paleontologist Othniel Charles Marsh. Specimens representing life stages from hatchling to adult have been found. As the archetypal ceratopsid, Triceratops is one of the most popular dinosaurs, and has been featured in film, postal stamps, and many other types of media.
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  • 01 Nov 2022
Topic Review
Grinder (Biohacking)
Grinders are people who apply the hacker ethic to improve their own bodies with do it yourself cybernetic devices or introducing Biochemicals into the body to enhance or change their bodies' functionality. Many grinders identify with the biopunk movement, open-source transhumanism, and techno-progressivism. The Grinder movement is strongly associated with the body modification movement and practices actual implantation of cybernetic devices in organic bodies as a method of working towards transhumanism, such as designing and installing do-it-yourself body-enhancements such as magnetic implants. Biohacking emerged in a growing trend of non-institutional science and technology development. According to Biohack.me, "Grinders are passionate individuals who believe the tools and knowledge of science belong to everyone. Grinders practice functional extreme body modification in an effort to improve the human condition. [Grinders] hack [them]selves with electronic hardware to extend and improve human capacities. Grinders believe in action, [thei]r bodies the experiment." "Biohacking" can also refer to managing one's own biology using a combination of medical, nutritional and electronic techniques. This may include the use of nootropics, non-toxic substances, and/or cybernetic devices for recording biometric data (as in the Quantified Self movement).
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  • 21 Nov 2022
Topic Review
Head-Up Display (Video Gaming)
In video gaming, the HUD (heads-up display) or status bar is the method by which information is visually relayed to the player as part of a game's user interface. It takes its name from the head-up displays used in modern aircraft. The HUD is frequently used to simultaneously display several pieces of information including the main character's health, items, and an indication of game progression (such as score or level).
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  • 31 Oct 2022
Topic Review Peer Reviewed
OAM of Light: Origins and Applications
Orbital Angular Momentum (OAM) of light is generating growing interest within the scientific community. This entry reviews the origins and applications of OAM. It is the counterpart of linear momentum for systems in rotation. The general expression of OAM is discussed, followed by its implications in terms of phase distribution and donut-shaped intensity profiles. Applications described include the generation of optical torque, telecommunications enhancement, and the rotational Doppler effect, emphasizing the role and consequences of angular momentum. In particular, its use to manipulate systems or to detect rotations is described. Finally, further developments and technological barriers are considered.
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  • 17 Sep 2025
Topic Review
PSA XUD
The PSA XUD is a Diesel engine designed and built by PSA - Peugeot and Citroën. It is an Indirect injection (IDI) engine, that uses a version of the Ricardo Consulting Engineers Ricardo Comet V prechamber cylinder head design. The engine comes in 1.8 L (1,769 cc) N/A, 1.8 Turbo, 1.9 L (1,905 cc) N/A, Turbo, 2.1 12 valve N/A and Turbo and was the predecessor to the HDI range of engines. Early HDi Engines were a PSA design, later 16 valve engines were jointly developed with Ford.
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  • 28 Oct 2022
Topic Review
Terminology of the British Isles
The terminology of the British Isles refers to the various words and phrases that are used to describe the different (and sometimes overlapping) geographical and political areas of the islands of Great Britain, Ireland, and the smaller islands which surround them. The terminology is often a source of confusion, partly owing to the similarity between some of the actual words used, but also because they are often used loosely. In addition, many of the words carry both geographical and political connotations which are affected by the history of the islands. The purpose of this article is to explain the meanings of and relationships among the terms in use; however many of these classifications are contentious and are the subject of disagreement (See the British Isles naming dispute).
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  • 03 Nov 2022
Topic Review
Semaphore Telegraph
A semaphore telegraph is an early system of conveying information by means of visual signals, using towers with pivoting shutters, also known as blades or paddles. Information is encoded by the position of the mechanical elements; it is read when the shutter is in a fixed position. The most widely used system was invented in 1792 in France by Claude Chappe, and was popular in the late eighteenth to early nineteenth centuries. Lines of relay towers with a semaphore rig at the top were built within line-of-sight of each other, at separations of 5–20 miles (8.0–32.2 km). Operators at each tower would watch the neighboring tower through a spyglass, and when the semaphore arms began to move spelling out a message, they would pass the message on to the next tower. This system was much faster than post riders for conveying a message over long distances, and also had cheaper long-term operating costs, once constructed. Semaphore lines were a precursor of the electrical telegraph, which would replace them half a century later, and would also be cheaper, faster, and more private. The line-of-sight distance between relay stations was limited by geography and weather, and prevented the optical telegraph from crossing wide expanses of water, unless a convenient island could be used for a relay station. Modern derivatives of the semaphore system include flag semaphore (a flag relay system) and the heliograph (optical telegraphy using mirror-directed sunlight reflections).
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  • 28 Nov 2022
Topic Review
Derringer
A derringer is a small handgun that is neither a revolver nor a semi/fully automatic pistol. It is not to be confused with mini-revolvers or pocket pistols, although some later derringers were manufactured with the pepperbox configuration. The modern derringer is often multi-barreled, and is generally the smallest usable handgun of any given caliber and barrel length due to the lack of a moving action, which takes up more space behind the barrel. It is frequently used by women because it is easily concealable in a purse or a stocking. The original Philadelphia Deringer was a muzzleloading caplock single-shot pistol introduced in 1825 by Henry Deringer. In total, approximately 15,000 Deringer pistols were manufactured. All were single barrel pistols with back-action percussion locks, typically .41 caliber with rifled bores, and walnut stocks. Barrel length varied from 1.5 to 6 in (38 to 152 mm), and the hardware was commonly a copper-nickel alloy known as "German silver". The term "derringer" (/ˈdɛrɪndʒər/) became a genericized misspelling during the reporting of the Lincoln assassination, which was committed with a concealed Philadelphia Deringer. Many copies of the original Philadelphia Deringer pistol were made by other gunmakers worldwide, and the name remained often misspelled; this misspelling soon became an alternative generic term for any pocket pistol, along with the generic phrase "palm pistol'", which Deringer's competitors invented and used in their advertising. With the advent of metallic cartridges, pistols produced in the modern form are still commonly called "derringers".
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  • 01 Nov 2022
Biography
Victor Hugo
Victor Marie Hugo French: [viktɔʁ maʁi yɡo] 26 February 1802 – 22 May 1885) was a French poet, novelist, and dramatist of the Romantic movement. Hugo is considered to be one of the greatest and best-known French writers. Outside of France, his most famous works are the novels Les Misérables, 1862, and The Hunchback of Notre-Dame (French: Notre-Dame de Paris), 1831. In France, Hugo is kno
  • 8.3K
  • 30 Nov 2022
Topic Review
BMW 5 Series Gran Turismo
The BMW 5 Series Gran Turismo (also referred to as "5 Series GT") models are the 5-door fastback versions of the F10 5 Series model range and use the model code F07. The F07 uses the F10 platform and shares many components with the other 5 Series models. It was released in 2009. Engine choices were turbocharged straight-6 petrol, straight-6 diesel and V8 petrol. At launch, all models were rear-wheel drive ("sDrive"), with all-wheel drive ("xDrive") models being added in 2010. For the following G30 generation, the Gran Turismo models were moved to the 6 Series model range and renamed the G32 6 Series Gran Turismo.
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  • 29 Sep 2022
Topic Review
Various Attachments for Implant Overdentures
This study presents an overview of the biomechanical and biomolecular aspects of various attachments for implant overdenture. We focused on the following topics: attachment systems, retention of various attachments, stress distribution with different attachments, the design and fabrication of attachments, digital techniques in overdenture attachments, and the effects of attachments in peri-implant health. We found that plastic resin is commonly used for ball and bar attachments, whereas nylon resin is commonly used in locator attachments. The locator system offers a valuable attachment option for implant-retained overdenture. Attachment retention reduces while lateral force increases with implant inclination in overdenture. The higher the retention of an overdenture attachment, the higher the transferred stresses. Additionally, clip loading produces more stress in implants and precision elements than bar-retained dentures. As such, we conclude that the ball and locator systems the best overdenture systems due to their superior tissue response, survival rate, and patient satisfaction.
  • 8.3K
  • 03 Nov 2021
Topic Review
Biochemistry of Hydrogen Peroxide
Hydrogen Peroxide (H2O2) is the nonionized 2-electron reduction product of unstable molecular oxygen (O2), which plays a central role in maintaining the redox cycle of living cells.
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  • 10 Jan 2022
Topic Review
Laser Absorption Spectroscopy
Laser absorption spectroscopy (LAS) is an absorption spectroscopic method that employs a laser as the light source and measures the chemical concentration based on detection of a variation of laser beam intensity after transmission along the optical path. 
  • 8.3K
  • 10 Sep 2020
Topic Review
List of Temples in Tamil Nadu
This is a list of temples in the Indian state of Tamil Nadu which is famed for Hindu temples, culture and tradition and commonly known as the Land of Temples. Tamil Nadu has more temples than any other states of India. Tamil Nadu is home to more than 40,000 Hindu, Buddhist, Jain, local deities, Ayyavazhi temples and is aptly called "the land of temples" by media. Many are at least 800 to 5000 years old and are found scattered all over the state. The rulers of various dynasties constructed these temples over centuries. Vimanas (storeys) and Gopuram (towering gateways to the temple complex) best characterize the temples of Tamil Nadu. As per Tamil Nadu Hindu Endowments Board, there are 38,615 temples. Most of the largest Hindu temples reside here. Studded with complex architecture, variety of sculptures, and rich inscriptions, the temples remain the very essence of the culture and heritage of Tamil land, with historical records dating back to at least 3,000 years. In Madurai, Meenakshi Amman Temple has high ‘Gopuram’ towers ornamented with colourful figures. On Pamban Island, Ramanathaswamy Temple is a famous pilgrimage site. The town of Kanyakumari, at India's southernmost tip, is the site of ritual sunrises. The state also abounds with temple tanks. The state has 2,359 temple tanks located in 1,586 temples. The government has identified 1,068 tanks for renovation. People from all over the world visits Temples of Tamil Nadu and it is the major Tourist attraction in India.
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  • 07 Nov 2022
Topic Review
Self-confidence
The concept of self-confidence is commonly used as self-assurance in one's personal judgment, ability, power, etc. One's self confidence increases from experiences of having satisfactorily completed particular activities. It is a positive belief that in the future one can generally accomplish what one wishes to do. Self-confidence is not the same as self-esteem, which is an evaluation of one's own worth, whereas self-confidence is more specifically trust in one's ability to achieve some goal, which one meta-analysis suggested is similar to generalization of self-efficacy. Abraham Maslow and many others after him have emphasized the need to distinguish between self-confidence as a generalized personality characteristic, and self-confidence with respect to a specific task, ability or challenge (i.e. self-efficacy). Self-confidence typically refers to general self-confidence. This is different from self-efficacy, which psychologist Albert Bandura has defined as a “belief in one’s ability to succeed in specific situations or accomplish a task” and therefore is the term that more accurately refers to specific self-confidence. Psychologists have long noted that a person can possess self-confidence that he or she can complete a specific task (self-efficacy) (e.g. cook a good meal or write a good novel) even though they may lack general self-confidence, or conversely be self-confident though they lack the self-efficacy to achieve a particular task (e.g. write a novel). These two types of self-confidence are, however, correlated with each other, and for this reason can be easily conflated.
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  • 18 Oct 2022
Topic Review
Slow Sand Filtration for Raw Water Treatment
Filtration methods are traditional techniques of water purification used by mankind since ancient times. By filtering, water can be cleaned of sand, silt, turbidity, scale, and other suspended particles. Modern slow sand filters (SSFs) for water purification were first used in the 19th century in England. Therefore, they are often called English filters. The first slow filter was built by the English engineer James Simpson in 1829 in London to purify water from the river Thames.
  • 8.3K
  • 02 Jun 2023
Topic Review
Two-Dimensional Space
Two-dimensional space (also known as 2D space, 2-space, or bi-dimensional space) is a geometric setting in which two values (called parameters) are required to determine the position of an element (i.e., point). The set [math]\displaystyle{ \mathbb{R}^2 }[/math] of pairs of real numbers with appropriate structure often serves as the canonical example of a two-dimensional Euclidean space. For a generalization of the concept, see dimension. Two-dimensional space can be seen as a projection of the physical universe onto a plane. Usually, it is thought of as a Euclidean space and the two dimensions are called length and width.
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  • 28 Nov 2022
Topic Review
Urban Open Space
In land-use planning, urban open space is open-space areas reserved for parks, "green spaces", and other open areas. The landscape of urban open spaces can range from playing fields to highly maintained environments to relatively natural landscapes. Generally considered open to the public, urban open spaces are sometimes privately owned, such as higher education campuses, neighborhood/community parks/gardens, and institutional or corporate grounds. Areas outside city boundaries, such as state and national parks as well as open space in the countryside, are not considered urban open space. Streets, piazzas, plazas and urban squares are not always defined as urban open space in land use planning.
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  • 14 Oct 2022
Topic Review
Polyelectrolyte
Polyelectrolytes are polymers of oppositely charged ions and their properties differ profoundly than their repeating units. Over recent years, much advancement has been made in the synthesis, characterization, and application of polyelectrolytes and polyelectrolyte complexes (PECs). It has many applications as flocculation agents, dispersant agents, and as super-plasticizers. In this article, the synthesis, types, characteristics, and application of PECs mainly for drug delivery and dynamics study are reviewed.
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  • 27 Oct 2020
Topic Review
Frogs in Culture
Frogs play a variety of roles in culture, appearing in folklore and fairy tales such as the Brothers Grimm story of The Frog Prince. In ancient Egypt and Mesopotamia, frogs symbolized fertility, while in classical antiquity, the Greeks and Romans associated frogs with fertility, harmony, and licentiousness. Frogs are the subjects of fables attributed to Aesop, of proverbs in various cultures, and of art. Frog characters such as Kermit the frog and Pepe the Frog feature in popular culture. They are eaten in some parts of the world including France. In Australia, a fondant dessert is known as frog cake.
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  • 27 Nov 2022
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