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Topic Review
Big Three Television Networks
The Big Three television networks are the three major traditional commercial broadcast television networks in the United States : the American Broadcasting Company (ABC), CBS (formerly known as the Columbia Broadcasting System) and the National Broadcasting Company (NBC). Until the 1980s, the Big Three networks dominated American television.
  • 4.6K
  • 01 Dec 2022
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.
  • 4.6K
  • 01 Nov 2022
Topic Review
Fly Ash
Fly ash or coal fly ash causes major global pollution in the form of solid waste and is classified as a “hazardous waste”, which is a by-product of thermal power plants produced during electricity production. Si, Al, Fe Ca, and Mg alone form more than 85% of the chemical compounds and glasses of most fly ashes. Fly ash has a chemical composition of 70–90%, as well as glasses of ferrous, alumina, silica, and CaO. Therefore, fly ash could act as a reliable and alternative source for ferrous, alumina, and silica. The ferrous fractions can be recovered by a simple magnetic separation method, while alumina and silica can be extracted by chemical or biological approaches. Alumina extraction is possible using both alkali- and acid-based methods, while silica is extracted by strong alkali, such as NaOH. Chemical extraction has a higher yield than the biological approaches, but the bio-based approaches are more environmentally friendly. Fly ash can also be used for the synthesis of zeolites by NaOH treatment of variable types, as fly ash is rich in alumino-silicates. The present review work deals with the recent advances in the field of the recovery and synthesis of ferrous, alumina, and silica micro and nanoparticles from fly ash.
  • 4.6K
  • 06 Apr 2021
Topic Review
Artificial Gravity in Fiction
Artificial gravity is a common theme in fiction, particularly science fiction.
  • 4.6K
  • 21 Oct 2022
Topic Review
Induction of Polyploidy
Polyploidy has the utmost importance in horticulture for the development of new ornamental varieties with desirable morphological traits referring to plant size and vigor, leaf thickness, larger flowers with thicker petals, intense color of leaves and flowers, long lasting flowers, compactness, dwarfness and restored fertility. Polyploidy may occur naturally due to the formation of unreduced gametes or can be artificially induced by doubling the number of chromosomes in somatic cells.
  • 4.6K
  • 21 Dec 2021
Topic Review
Smart Grid Management, Control, and Operation
Smart grid management, control and operation (SGMCO) are key tasks for maintaining their proper functioning as well as for their extension and expansion. The current challenges of power generation, distribution, transmission, and consumption, as well as growing energy demand, facilitate the integration of a large number of smart grids with renewable energy generators and physical information systems, while smart grids are moving toward distribution and decentralization in response to the evolving application of the Internet of Energy (IoE). SGMCO handles not only traditional management, control, and operations, but also the future challenges for smart grids: Collaboration between stakeholders, control of network imbalances (e.g. frequency and voltage regulation), data analysis and management, decentralized network management and operation, and security and privacy.
  • 4.6K
  • 10 Jan 2022
Topic Review
Gaulish Language
Gaulish was an ancient Celtic language that was spoken in parts of Continental Europe before and during the period of the Roman Empire. In the narrow sense, Gaulish was the language spoken by the Celtic inhabitants of Gaul (modern-day France, Luxembourg, Belgium, most of Switzerland, Northern Italy, as well as the parts of the Netherlands and Germany on the west bank of the Rhine). In a wider sense, it also comprises varieties of Celtic that were spoken across much of central Europe ("Noric"), parts of the Balkans, and Anatolia ("Galatian"), which are thought to have been closely related. The more divergent Lepontic of Northern Italy has also sometimes been subsumed under Gaulish. Together with Lepontic and the Celtiberian language spoken in the Iberian Peninsula, Gaulish helps form the geographic group of Continental Celtic languages. The precise linguistic relationships among them, as well as between them and the modern Insular Celtic languages, are uncertain and a matter of ongoing debate because of their sparse attestation. Gaulish is found in some 800 (often fragmentary) inscriptions including calendars, pottery accounts, funeral monuments, short dedications to gods, coin inscriptions, statements of ownership, and other texts, possibly curse tablets. Gaulish texts were first written in the Greek alphabet in southern France and in a variety of the Old Italic script in northern Italy. After the Roman conquest of those regions, writing shifted to the use of the Latin alphabet. During his conquest of Gaul, Caesar reported that the Helvetii were in possession of documents in the Greek script, and all Gaulish coins used the Greek script until about 50 BC. Gaulish in Western Europe was supplanted by Vulgar Latin and various Germanic languages from around the 5th century AD onwards. It is thought to have gone extinct some time around the late 6th century.
  • 4.6K
  • 01 Dec 2022
Topic Review
Benefits of Agricultural Biotechnology
As agricultural production approaches a bottleneck due to limited arable lands, extreme weather, and increasing food demand, novel tools are needed to produce more resilient, efficient, and high-yielding crops to ensure global food security. Modern biotechnology tools with improved specificity and efficiency could eventually become the main driver of agricultural improvement, overcoming the limitations of conventional practices in improving crops. 
  • 4.6K
  • 23 May 2022
Topic Review
African Humid Period
The African humid period (AHP) is a climate period in Africa during the late Pleistocene and Holocene geologic epochs, when northern Africa was wetter than today. The covering of much of the Sahara desert by grasses, trees and lakes was caused by changes in Earth's orbit around the Sun; changes in vegetation and dust in the Sahara which strengthened the African monsoon; and increased greenhouse gases, which may, or may not imply that anthropogenic global warming could result in a shrinkage of the Sahara desert. During the preceding last glacial maximum, the Sahara contained extensive dune fields and was mostly uninhabited. It was much larger than today, but its lakes and rivers such as Lake Victoria and the White Nile were either dry or at low levels. The humid period began about 14,600–14,500 years ago at the end of Heinrich event 1, simultaneously to the Bølling-Allerød warming. Rivers and lakes such as Lake Chad formed or expanded, glaciers grew on Mount Kilimanjaro and the Sahara retreated. Two major dry fluctuations occurred; during the Younger Dryas and the short 8.2 kiloyear event. The African humid period ended 6,000–5,000 years ago during the Piora Oscillation cold period. While some evidence points to an end 5,500 years ago, in the Sahel, Arabia and East Africa the period appears to have taken place in several steps such as the 4.2 kiloyear event. The AHP led to a widespread settlement of the Sahara and the Arabian Deserts, and had a profound effect on African cultures, such as the birth of the Pharaonic civilization. They lived as hunter-gatherers until the agricultural revolution and domesticated cattle, goats and sheep. They left archeological sites and artifacts such as one of the oldest ships in the world, and rock paintings such as those in the Cave of Swimmers and in the Acacus Mountains. Earlier humid periods in Africa were postulated after the discovery of these rock paintings in now-inhospitable parts of the Sahara. When the period ended, humans gradually abandoned the desert in favour of regions with more secure water supplies, such as the Nile Valley and Mesopotamia, where they gave rise to early complex societies.
  • 4.5K
  • 10 Nov 2022
Topic Review
Artificial Neural Networks
Artificial Intelligence (AI) researches and builds intelligent software and machines, provides a particular solution to a particular defined complex problem. To carry out these tasks, it uses models and algorithms such as genetic algorithms, particle swarm optimization, artificial neural networks (ANNs), and hybrid models (two or more of the above). ANNs are flexible to accommodate non-linear and non-physical data; however, they require large multidimensional data set to reduce the risk of extrapolation. ANNs are widely used in different branches of science for their learning ability and adaptability to various settings.
  • 4.5K
  • 12 Apr 2021
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