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Livyatan is an extinct genus of macroraptorial sperm whale containing one known species: L. melvillei. The genus name was inspired by the biblical sea monster Leviathan, and the species name by Herman Melville, the author of the famous novel Moby-Dick about a white bull sperm whale. Herman Melville often referred to wh... | Livyatan | Wikipedia | 459 | 27900561 | https://en.wikipedia.org/wiki/Livyatan | Biology and health sciences | Cetaceans | Animals |
Holotype and naming
In November 2008, a partially preserved skull, as well as teeth and the lower jaw, belonging to L., the holotype specimen MUSM 1676, were discovered in the coastal desert of Peru in the sediments of the Pisco Formation, southwest of the city of Ica. Klaas Post, a researcher for the Natural Histor... | Livyatan | Wikipedia | 469 | 27900561 | https://en.wikipedia.org/wiki/Livyatan | Biology and health sciences | Cetaceans | Animals |
In 2016 in Beaumaris Bay, Australia, a large sperm whale tooth measuring , specimen NMV P16205, was discovered in Pliocene strata by a local named Murray Orr, and was nicknamed the "Beaumaris sperm whale" or the "giant sperm whale". The tooth was donated to Museums Victoria at Melbourne. Though it has not been given a ... | Livyatan | Wikipedia | 467 | 27900561 | https://en.wikipedia.org/wiki/Livyatan | Biology and health sciences | Cetaceans | Animals |
In 2023, graduate student Kristin Watmore and paleontologist Donald Prothero reported in a preprint a giant sperm whale tooth identified as cf. Livaytan discovered in Mission Viejo, California during housing development during the 1980s and '90s. The tooth resided in the Orange County Paleontological Collection catalog... | Livyatan | Wikipedia | 462 | 27900561 | https://en.wikipedia.org/wiki/Livyatan | Biology and health sciences | Cetaceans | Animals |
Skull
The holotype skull of Livyatan was about long. Like other raptorial sperm whales, Livyatan had a wide gap in between the temporal fossae on the sides of the skull and the zygomatic processes on the front of the skull, indicating a large space for holding strong temporal muscles, which are the most powerful muscl... | Livyatan | Wikipedia | 356 | 27900561 | https://en.wikipedia.org/wiki/Livyatan | Biology and health sciences | Cetaceans | Animals |
Teeth
Unlike the modern sperm whale, Livyatan had functional teeth in both jaws. The wearing on the teeth indicates that the teeth sheared past each other while biting down, meaning it could bite off large portions of flesh from its prey. Also, the teeth were deeply embedded into the gums and could interlock, which w... | Livyatan | Wikipedia | 479 | 27900561 | https://en.wikipedia.org/wiki/Livyatan | Biology and health sciences | Cetaceans | Animals |
All tooth sockets were cylindrical and single-rooted. The tooth sockets increased in size from the first to the fourth and then decreased, the fourth being the largest at around in diameter in the upper jaws, which is the largest of any known whale species. The tooth sockets were smaller in the lower jaw than they wer... | Livyatan | Wikipedia | 363 | 27900561 | https://en.wikipedia.org/wiki/Livyatan | Biology and health sciences | Cetaceans | Animals |
Classification
Livyatan was part of a fossil stem group of hyper-predatory sperm whales commonly known as macroraptorial sperm whales, or raptorial sperm whales, alongside the extinct whales Brygmophyseter, Acrophyseter and Zygophyseter. This group is known for having large, functional teeth in both the upper and lower... | Livyatan | Wikipedia | 483 | 27900561 | https://en.wikipedia.org/wiki/Livyatan | Biology and health sciences | Cetaceans | Animals |
Hunting
Livyatan was an apex predator, and probably had a profound impact on the structuring of Miocene marine communities. Using its large and deeply rooted teeth, it is likely to have hunted large prey near the surface, its diet probably consisting mainly of medium-sized baleen whales ranging from in length. It prob... | Livyatan | Wikipedia | 414 | 27900561 | https://en.wikipedia.org/wiki/Livyatan | Biology and health sciences | Cetaceans | Animals |
Another theory says that the enlarged forehead caused by the presence of the spermaceti organ is used in all sperm whales between males fighting for females during mating season by head-butting each other, including Livyatan and the modern sperm whale. It may have also been used to ram into prey; if this is the case, i... | Livyatan | Wikipedia | 357 | 27900561 | https://en.wikipedia.org/wiki/Livyatan | Biology and health sciences | Cetaceans | Animals |
The holotype of L. melvillei is from the Tortonian stage of the Upper Miocene 9.9–8.9 mya in the Pisco Formation of Peru, which is known for its well-preserved assemblage of marine vertebrates. Among the baleen whales found, the most common was an undescribed species of cetotheriid whale measuring around , and most of ... | Livyatan | Wikipedia | 393 | 27900561 | https://en.wikipedia.org/wiki/Livyatan | Biology and health sciences | Cetaceans | Animals |
L. melvillei is also known from the Bahía Inglesa Formation of Chile, whose fossiliferous beds are dated between the Tortonian and Messinian 9.03–6.45 mya. Like the Pisco Formation, the Bahía Inglesa Formation famously holds one of the richest marine vertebrate assemblages. Baleen whale remains include ancient minke wh... | Livyatan | Wikipedia | 456 | 27900561 | https://en.wikipedia.org/wiki/Livyatan | Biology and health sciences | Cetaceans | Animals |
The South African teeth attributed as cf. Livyatan are from the Avontuur Member of the Alexander Bay Formation near the village of Hondeklip Bay, Namaqualand, which is also dated to around 5mya in the Pliocene. The Hondeklip Bay locality enjoys a rich heritage of marine fossils, whose diversity may have been thanks to ... | Livyatan | Wikipedia | 460 | 27900561 | https://en.wikipedia.org/wiki/Livyatan | Biology and health sciences | Cetaceans | Animals |
In mathematics, a space is a set (sometimes known as a universe) endowed with a structure defining the relationships among the elements of the set.
A subspace is a subset of the parent space which retains the same structure.
While modern mathematics uses many types of spaces, such as Euclidean spaces, linear spaces, to... | Space (mathematics) | Wikipedia | 484 | 5308894 | https://en.wikipedia.org/wiki/Space%20%28mathematics%29 | Mathematics | Set theory | null |
Two equivalence relations between geometric figures were used: congruence and similarity. Translations, rotations and reflections transform a figure into congruent figures; homotheties — into similar figures. For example, all circles are mutually similar, but ellipses are not similar to circles. A third equivalence rel... | Space (mathematics) | Wikipedia | 441 | 5308894 | https://en.wikipedia.org/wiki/Space%20%28mathematics%29 | Mathematics | Set theory | null |
A Euclidean model of a non-Euclidean geometry is a choice of some objects existing in Euclidean space and some relations between these objects that satisfy all axioms (and therefore, all theorems) of the non-Euclidean geometry. These Euclidean objects and relations "play" the non-Euclidean geometry like contemporary ac... | Space (mathematics) | Wikipedia | 433 | 5308894 | https://en.wikipedia.org/wiki/Space%20%28mathematics%29 | Mathematics | Set theory | null |
Simultaneously, numbers began to displace geometry as the foundation of mathematics. For instance, in Richard Dedekind's 1872 essay Stetigkeit und irrationale Zahlen (Continuity and irrational numbers), he asserts that points on a line ought to have the properties of Dedekind cuts, and that therefore a line was the sa... | Space (mathematics) | Wikipedia | 434 | 5308894 | https://en.wikipedia.org/wiki/Space%20%28mathematics%29 | Mathematics | Set theory | null |
Three taxonomic ranks
While each type of space has its own definition, the general idea of "space" evades formalization. Some structures are called spaces, other are not, without a formal criterion. Moreover, there is no consensus on the general idea of "structure".
According to Pudlák, "Mathematics [...] cannot be exp... | Space (mathematics) | Wikipedia | 430 | 5308894 | https://en.wikipedia.org/wiki/Space%20%28mathematics%29 | Mathematics | Set theory | null |
The third-level classification distinguishes, for example, between spaces of different dimension, but does not distinguish between a plane of a three-dimensional Euclidean space, treated as a two-dimensional Euclidean space, and the set of all pairs of real numbers, also treated as a two-dimensional Euclidean space. Li... | Space (mathematics) | Wikipedia | 404 | 5308894 | https://en.wikipedia.org/wiki/Space%20%28mathematics%29 | Mathematics | Set theory | null |
Relations between species of spaces
Topological notions (continuity, convergence, open sets, closed sets etc.) are defined naturally in every Euclidean space. In other words, every Euclidean space is also a topological space. Every isomorphism between two Euclidean spaces is also an isomorphism between the correspondin... | Space (mathematics) | Wikipedia | 463 | 5308894 | https://en.wikipedia.org/wiki/Space%20%28mathematics%29 | Mathematics | Set theory | null |
In contrast, the transition from "3-dim Euclidean" to "Euclidean" is not forgetful; a Euclidean space need not be 3-dimensional, but if it happens to be 3-dimensional, it is full-fledged, no structure is lost. In other words, the latter transition is injective (one-to-one), while the former transition is not injective ... | Space (mathematics) | Wikipedia | 405 | 5308894 | https://en.wikipedia.org/wiki/Space%20%28mathematics%29 | Mathematics | Set theory | null |
The diagram on Fig. 4 is commutative. That is, all directed paths in the diagram with the same start and endpoints lead to the same result. Other diagrams below are also commutative, except for dashed arrows on Fig. 9. The arrow from "topological" to "measurable" is dashed for the reason explained there: "In order to t... | Space (mathematics) | Wikipedia | 368 | 5308894 | https://en.wikipedia.org/wiki/Space%20%28mathematics%29 | Mathematics | Set theory | null |
Hipparionini is a tribe of three-toed horses in the subfamily Equinae. They had body forms similar to modern equines, with high-crowned teeth. They first appeared in North America during the Early Miocene around 17 million years ago, before migrating into the Old World around 11.4-11.0 million years ago. The youngest s... | Hipparionini | Wikipedia | 421 | 37285387 | https://en.wikipedia.org/wiki/Hipparionini | Biology and health sciences | Equidae | Animals |
The geomagnetic poles are antipodal points where the axis of a best-fitting dipole intersects the surface of Earth. This theoretical dipole is equivalent to a powerful bar magnet at the center of Earth, and comes closer than any other point dipole model to describing the magnetic field observed at Earth's surface. In c... | Geomagnetic pole | Wikipedia | 307 | 31696675 | https://en.wikipedia.org/wiki/Geomagnetic%20pole | Physical sciences | Geophysics | Earth science |
Definition
As a first-order approximation, the Earth's magnetic field can be modeled as a simple dipole (like a bar magnet), tilted about 9.6° with respect to the Earth's rotation axis (which defines the Geographic North and Geographic South Poles) and centered at the Earth's center. The North and South Geomagnetic Pol... | Geomagnetic pole | Wikipedia | 509 | 31696675 | https://en.wikipedia.org/wiki/Geomagnetic%20pole | Physical sciences | Geophysics | Earth science |
The locations of geomagnetic poles are calculated by a statistical fit to measurements of the Earth's field by satellites and in geomagnetic observatories. This can be the International Geomagnetic Reference Field (covering a wide time-span in history) or the U.S. World Magnetic Model (only covering a five-year period)... | Geomagnetic pole | Wikipedia | 404 | 31696675 | https://en.wikipedia.org/wiki/Geomagnetic%20pole | Physical sciences | Geophysics | Earth science |
The Manchester computers were an innovative series of stored-program electronic computers developed during the 30-year period between 1947 and 1977 by a small team at the University of Manchester, under the leadership of Tom Kilburn. They included the world's first stored-program computer, the world's first transistori... | Manchester computers | Wikipedia | 478 | 21629856 | https://en.wikipedia.org/wiki/Manchester%20computers | Technology | Early computers | null |
Development of the Manchester Mark 1 began in August 1948, with the initial aim of providing the university with a more realistic computing facility. In October 1948 UK Government Chief Scientist Ben Lockspeiser was given a demonstration of the prototype, and was so impressed that he immediately initiated a government ... | Manchester computers | Wikipedia | 418 | 21629856 | https://en.wikipedia.org/wiki/Manchester%20computers | Technology | Early computers | null |
Two versions of the machine were produced. The first was the world's first transistorised computer, a prototype, and became operational on 16 November 1953. "The 48-bit machine used 92 point-contact transistors and 550 diodes". The second version was completed in April 1955. The 1955 version used 250 junction transisto... | Manchester computers | Wikipedia | 348 | 21629856 | https://en.wikipedia.org/wiki/Manchester%20computers | Technology | Early computers | null |
At the end of 1958 Ferranti agreed to collaborate with Manchester University on the project, and the computer was shortly afterwards renamed Atlas, with the joint venture under the control of Tom Kilburn. The first Atlas was officially commissioned on 7 December 1962, and was considered at that time to be the most powe... | Manchester computers | Wikipedia | 512 | 21629856 | https://en.wikipedia.org/wiki/Manchester%20computers | Technology | Early computers | null |
The most significant novel features of the MU5 processor were its instruction set and the use of associative memory to speed up operand and instruction accesses. The instruction set was designed to permit the generation of efficient object code by compilers, to allow for a pipeline organisation of the processor and to ... | Manchester computers | Wikipedia | 403 | 21629856 | https://en.wikipedia.org/wiki/Manchester%20computers | Technology | Early computers | null |
Once MU5 was fully operational, a new project was initiated to produce its successor, MU6. MU6 was intended to be a range of processors: MU6P, an advanced microprocessor architecture intended for use as a personal computer,
MU6-G, a high performance machine for general or scientific applications and MU6V, a parallel ve... | Manchester computers | Wikipedia | 281 | 21629856 | https://en.wikipedia.org/wiki/Manchester%20computers | Technology | Early computers | null |
In string theory and related theories (such as supergravity theories), a brane is a physical object that generalizes the notion of a zero-dimensional point particle, a one-dimensional string, or a two-dimensional membrane to higher-dimensional objects. Branes are dynamical objects which can propagate through spacetim... | Brane | Wikipedia | 483 | 26010282 | https://en.wikipedia.org/wiki/Brane | Physical sciences | Particle physics: General | Physics |
Categorical description
Mathematically, branes can be described using the notion of a category. This is a mathematical structure consisting of objects, and for any pair of objects, a set of morphisms between them. In most examples, the objects are mathematical structures (such as sets, vector spaces, or topological sp... | Brane | Wikipedia | 505 | 26010282 | https://en.wikipedia.org/wiki/Brane | Physical sciences | Particle physics: General | Physics |
Tinder is an online dating and geosocial networking application launched in 2012. On Tinder, users "swipe right" to like or "swipe left" to dislike other users' profiles, which include their photos, a short bio, and some of their interests. Tinder uses a "double opt-in" system, also called "matching", where two users ... | Tinder (app) | Wikipedia | 493 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
2013: Swipe feature developed
Tinder's selection function, which was initially click-based, evolved into the company's swipe feature. The feature was established when Rad and Badeen, interested in gamification, modeled the feature on a deck of cards. Badeen then streamlined the action after a trial on a bathroom mirror... | Tinder (app) | Wikipedia | 476 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
In March 2017, Tinder launched Tinder Online, a web-optimized version of the app. Initially, it was available only in Argentina, Brazil, Colombia, Indonesia, Italy, Mexico, the Philippines, and Sweden, and did not include special features such as "Super Likes" or "Tinder Boost". Tinder Online launched globally in Septe... | Tinder (app) | Wikipedia | 474 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
On May 10, it was reported that Tinder was planning for a lighter version of the app, Tinder Lite, aimed at growing markets where data usage, bandwidth and storage space are a concern.
Tinder had 5.2 million paying subscribers at the end of 2019's second quarter, up 1.5 million from the year-ago quarter and up 503,000... | Tinder (app) | Wikipedia | 504 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
On November 4, Tinder reported higher than expected third-quarter earnings and significant platform growth amid the pandemic: the app grew its user base by 15% and its subscriber count by 16% since the third quarter of 2019. According to Business Insider, Tinder's growth was fueled by a large population that turned to ... | Tinder (app) | Wikipedia | 464 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
In May 2023, Match Group announced its intent to restrict access to Tinder in Russia and withdraw from the Russian market by June 30, 2023, citing the need to protect human rights. In doing so, it became one of many Western companies to leave Russia after the Russian invasion of Ukraine. Tinder became unavailable in Ru... | Tinder (app) | Wikipedia | 507 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
In March 2014, media and internet conglomerate IAC increased its majority stake in Tinder, a move that is believed to have valued Tinder at several billion dollars. In July 2015, Tinder was valued at $1.35 billion by Bank of America Merrill Lynch based upon an estimate of $27 per user on an estimated user base of 50 mi... | Tinder (app) | Wikipedia | 420 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
Users
Tinder is used widely throughout the world and available in over 190 countries and 56 languages. As of September 2021, an estimated 75 million people used the app every month. In late 2014, Tinder users averaged 12 million matches per day. To get those 12 million matches, users collectively made around 1 billion ... | Tinder (app) | Wikipedia | 512 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
In December 2018, The Verge reported that Tinder had dismissed its vice president of marketing and communication, Rosette Pambakian. Pambakian alleged former Match Group and IAC CEO Greg Blatt sexually assaulted her in a hotel room after a company party in December 2016. She further accused the company of firing her wh... | Tinder (app) | Wikipedia | 413 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
In July 2017, a study published in Advances in Intelligent Systems and Computing found that Tinder users are excessively willing to disclose their personally identifiable information. In September 2017, The Guardian published an article by a journalist who requested all data that the Tinder app had recorded about her f... | Tinder (app) | Wikipedia | 425 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
In March 2018, an article in The Cut reported that a trans woman sued Tinder for removing her profile and refusing to explain why it had been deleted. The article further reported that many transgender people had their accounts reported and banned, some within several hours of opening them. In October 2019, PinkNews re... | Tinder (app) | Wikipedia | 418 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
Men use dating apps and websites more than women do—both by frequency of use and number of users. According to Statista, as of March 2021, 75.8% of the U.S. Tinder user base is male and 24.2% is female. The first study on swiping strategies revealed that "men tend to like a large proportion of the women they view but r... | Tinder (app) | Wikipedia | 301 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
In August 2015, journalist Nancy Jo Sales wrote in Vanity Fair that Tinder operates within a culture of users seeking sex without relationships. In 2017, the Department of Communications Studies at Texas Tech University conducted a study to see how infidelity was connected to Tinder. The experiment was conducted on 550... | Tinder (app) | Wikipedia | 247 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
Before Tinder, most online dating services matched people according to their autobiographical information, such as interests, hobbies, and future plans. Tinder places a higher weight on first impressions. For social scientists studying human courtship behavior, Tinder offers a much simpler environment than its predeces... | Tinder (app) | Wikipedia | 410 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
Tyson and his team found that even though the men-to-women ratio of their data set was approximately one, the male profiles received 8,248 matches while the female profiles received 532, because the vast majority of the matches for both the male and female profiles came from male profiles (with 86% of the matches for t... | Tinder (app) | Wikipedia | 124 | 40078184 | https://en.wikipedia.org/wiki/Tinder%20%28app%29 | Technology | Social network and blogging | null |
Non-stoichiometric compounds are chemical compounds, almost always solid inorganic compounds, having elemental composition whose proportions cannot be represented by a ratio of small natural numbers (i.e. an empirical formula); most often, in such materials, some small percentage of atoms are missing or too many atoms ... | Non-stoichiometric compound | Wikipedia | 293 | 3947316 | https://en.wikipedia.org/wiki/Non-stoichiometric%20compound | Physical sciences | Alloys and ceramic compounds | Chemistry |
Iron oxides
Nonstoichiometry is pervasive for metal oxides, especially when the metal is not in its highest oxidation state. For example, although wüstite (ferrous oxide) has an ideal (stoichiometric) formula , the actual stoichiometry is closer to . The non-stoichiometry reflect the ease of oxidation of to effectiv... | Non-stoichiometric compound | Wikipedia | 510 | 3947316 | https://en.wikipedia.org/wiki/Non-stoichiometric%20compound | Physical sciences | Alloys and ceramic compounds | Chemistry |
Tungsten oxides
It is sometimes difficult to determine if a material is non-stoichiometric or if the formula is best represented by large numbers. The oxides of tungsten illustrate this situation. Starting from the idealized material tungsten trioxide, one can generate a series of related materials that are slightly ... | Non-stoichiometric compound | Wikipedia | 508 | 3947316 | https://en.wikipedia.org/wiki/Non-stoichiometric%20compound | Physical sciences | Alloys and ceramic compounds | Chemistry |
Superconductivity
Many superconductors are non-stoichiometric. For example, yttrium barium copper oxide, arguably the most notable high-temperature superconductor, is a non-stoichiometric solid with the formula YxBa2Cu3O7−x. The critical temperature of the superconductor depends on the exact value of x. The stoichiom... | Non-stoichiometric compound | Wikipedia | 244 | 3947316 | https://en.wikipedia.org/wiki/Non-stoichiometric%20compound | Physical sciences | Alloys and ceramic compounds | Chemistry |
The free surface effect is a mechanism which can cause a watercraft to become unstable and capsize.
It refers to the tendency of liquids — and of unbound aggregates of small solid objects, like seeds, gravel, or crushed ore, whose behavior approximates that of liquids — to move in response to changes in the attitude o... | Free surface effect | Wikipedia | 409 | 3947744 | https://en.wikipedia.org/wiki/Free%20surface%20effect | Physical sciences | Fluid mechanics | Physics |
The momentum of large volumes of moving liquids cause significant dynamic forces, which act against the righting effect. When the vessel returns to vertical the roll continues and the effect is repeated on the opposite side. In heavy seas, this can become a positive feedback loop, causing each roll to become more and m... | Free surface effect | Wikipedia | 465 | 3947744 | https://en.wikipedia.org/wiki/Free%20surface%20effect | Physical sciences | Fluid mechanics | Physics |
Effects on land and aircraft
The free surface effect can affect any kind of craft, including watercraft (where it is most common), bulk cargo or liquid tanker semi-trailers and trucks (causing either jackknifing or roll-overs), and aircraft (especially fire-fighting water-droppers and refueling tankers where baffles mi... | Free surface effect | Wikipedia | 177 | 3947744 | https://en.wikipedia.org/wiki/Free%20surface%20effect | Physical sciences | Fluid mechanics | Physics |
A cyclic compound (or ring compound) is a term for a compound in the field of chemistry in which one or more series of atoms in the compound is connected to form a ring. Rings may vary in size from three to many atoms, and include examples where all the atoms are carbon (i.e., are carbocycles), none of the atoms are ca... | Cyclic compound | Wikipedia | 413 | 3949010 | https://en.wikipedia.org/wiki/Cyclic%20compound | Physical sciences | Substance | Chemistry |
Structure and classification
A cyclic compound or ring compound is a compound in which at least some its atoms are connected to form a ring. Rings vary in size from three to many tens or even hundreds of atoms. Examples of ring compounds readily include cases where:
all the atoms are carbon (i.e., are carbocycles),
... | Cyclic compound | Wikipedia | 390 | 3949010 | https://en.wikipedia.org/wiki/Cyclic%20compound | Physical sciences | Substance | Chemistry |
Inorganic cyclic compounds
Inorganic atoms form cyclic compounds as well. Examples include sulfur and nitrogen (e.g. heptasulfur imide , trithiazyl trichloride , tetrasulfur tetranitride ), silicon (e.g., cyclopentasilane ), phosphorus and nitrogen (e.g., hexachlorophosphazene ), phosphorus and oxygen (e.g., metaphosph... | Cyclic compound | Wikipedia | 348 | 3949010 | https://en.wikipedia.org/wiki/Cyclic%20compound | Physical sciences | Substance | Chemistry |
The term macrocycle is used for compounds having a rings of 8 or more atoms. Macrocycles may be fully carbocyclic (rings containing only carbon atoms, e.g. cyclooctane), heterocyclic containing both carbon and non-carbon atoms (e.g. lactones and lactams containing rings of 8 or more atoms), or non-carbon (containing on... | Cyclic compound | Wikipedia | 478 | 3949010 | https://en.wikipedia.org/wiki/Cyclic%20compound | Physical sciences | Substance | Chemistry |
Stereochemistry
The closing of atoms into rings may lock particular atoms with distinct substitution by functional groups such that the result is stereochemistry and chirality of the compound, including some manifestations that are unique to rings (e.g., configurational isomers).
Conformational isomerism
Depending ... | Cyclic compound | Wikipedia | 418 | 3949010 | https://en.wikipedia.org/wiki/Cyclic%20compound | Physical sciences | Substance | Chemistry |
Cyclic compounds may or may not exhibit aromaticity; benzene is an example of an aromatic cyclic compound, while cyclohexane is non-aromatic. In organic chemistry, the term aromaticity is used to describe a cyclic (ring-shaped), planar (flat) molecule that exhibits unusual stability as compared to other geometric or co... | Cyclic compound | Wikipedia | 402 | 3949010 | https://en.wikipedia.org/wiki/Cyclic%20compound | Physical sciences | Substance | Chemistry |
In terms of the electronic nature of the molecule, aromaticity describes a conjugated system often made of alternating single and double bonds in a ring. This configuration allows for the electrons in the molecule's pi system to be delocalized around the ring, increasing the molecule's stability. The molecule cannot be... | Cyclic compound | Wikipedia | 459 | 3949010 | https://en.wikipedia.org/wiki/Cyclic%20compound | Physical sciences | Substance | Chemistry |
Ring-closing reactions
In organic chemistry, a variety of synthetic procedures are particularly useful in closing carbocyclic and other rings; these are termed ring-closing reactions. Examples include:
alkyne trimerisation;
the Bergman cyclization of an enediyne;
the Diels–Alder, between a conjugated diene and a sub... | Cyclic compound | Wikipedia | 403 | 3949010 | https://en.wikipedia.org/wiki/Cyclic%20compound | Physical sciences | Substance | Chemistry |
The Blue Java (also known as the blue banana, Ice Cream banana, Vanilla Banana, Hawaiian banana, Ney Mannan, Krie, or Cenizo) is a hardy, cold-tolerant banana cultivar known for its sweet aromatic fruit, which is said to have an ice cream-like consistency and flavor reminiscent of vanilla. It is native to Southeast Asi... | Blue Java banana | Wikipedia | 443 | 23139600 | https://en.wikipedia.org/wiki/Blue%20Java%20banana | Biology and health sciences | Tropical and tropical-like fruit | Plants |
Rhinocerotoidea is a superfamily of perissodactyls that appeared 56 million years ago in the Paleocene. They included four extinct families, the Amynodontidae, the Hyracodontidae, the Paraceratheriidae, and the Eggysodontidae. The only extant family is the Rhinocerotidae (true rhinoceroses), which survives as five livi... | Rhinocerotoidea | Wikipedia | 174 | 37299388 | https://en.wikipedia.org/wiki/Rhinocerotoidea | Biology and health sciences | Perissodactyla | Animals |
The Giant Void (also known as the Giant Void in NGH, Canes Venatici Supervoid, and AR-Lp 36) is an extremely large region of space with an underdensity of galaxies and located in the constellation Canes Venatici. It is the second-largest-confirmed void to date, with an estimated diameter of 300 to 400 Mpc (1 to 1.3 bil... | Giant Void | Wikipedia | 307 | 41529802 | https://en.wikipedia.org/wiki/Giant%20Void | Physical sciences | Notable patches of universe | Astronomy |
Effects of climate change are well documented and growing for Earth's natural environment and human societies. Changes to the climate system include an overall warming trend, changes to precipitation patterns, and more extreme weather. As the climate changes it impacts the natural environment with effects such as more... | Effects of climate change | Wikipedia | 371 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Humans are vulnerable to climate change in many ways. Sources of food and fresh water can be threatened by environmental changes. Human health can be impacted by weather extremes or by ripple effects like the spread of infectious diseases. Economic impacts include changes to agriculture, fisheries, and forestry. Higher... | Effects of climate change | Wikipedia | 401 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
How much the world warms depends on human greenhouse gas emissions and on how sensitive the climate is to greenhouse gases. The more carbon dioxide () is emitted in the 21st century the hotter the world will be by 2100. For a doubling of greenhouse gas concentrations, the global mean temperature would rise by about . I... | Effects of climate change | Wikipedia | 500 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Heatwaves over land have become more frequent and more intense in almost all world regions since the 1950s, due to climate change. Heat waves are more likely to occur simultaneously with droughts. Marine heatwaves are twice as likely as they were in 1980. Climate change will lead to more very hot days and fewer very co... | Effects of climate change | Wikipedia | 471 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Climate change has increased contrasts in rainfall amounts between wet and dry seasons. Wet seasons are getting wetter and dry seasons are getting drier. In the northern high latitudes, warming has also caused an increase in the amount of snow and rain. In the Southern Hemisphere, the rain associated with the storm tra... | Effects of climate change | Wikipedia | 402 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Droughts
Climate change affects many factors associated with droughts. These include how much rain falls and how fast the rain evaporates again. Warming over land increases the severity and frequency of droughts around much of the world. In some tropical and subtropical regions of the world, there will probably be les... | Effects of climate change | Wikipedia | 512 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Seismic and volcanic activity
In regions sensitive to climate change the frequency and intensity of eruptions will change as global warming increases. Glacier retreat and stronger precipitation can increase the chances for an eruption. As of 2024, government agencies are already addressing these changes and scientist... | Effects of climate change | Wikipedia | 482 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Since the beginning of the twentieth century, there has been a widespread retreat of glaciers. Those glaciers that are not associated with the polar ice sheets lost around 8% of their mass between 1971 and 2019. In the Andes in South America and in the Himalayas in Asia, the retreat of glaciers could impact water suppl... | Effects of climate change | Wikipedia | 482 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Sea ice in the Arctic has declined in recent decades in area and volume due to climate change. It has been melting more in summer than it refreezes in winter. The decline of sea ice in the Arctic has been accelerating during the early twenty-first century. It has a rate of decline of 4.7% per decade. It has declined o... | Effects of climate change | Wikipedia | 425 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
The impacts of climate change on nature are likely to become bigger in the next few decades. The stresses caused by climate change, combine with other stresses on ecological systems such as land conversion, land degradation, harvesting, and pollution. They threaten substantial damage to unique ecosystems. They can even... | Effects of climate change | Wikipedia | 225 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Climate change is a major driver of biodiversity loss in different land types. These include cool conifer forests, savannas, mediterranean-climate systems, tropical forests, and the Arctic tundra. In other ecosystems, land-use change may be a stronger driver of biodiversity loss, at least in the near term. Beyond 2050,... | Effects of climate change | Wikipedia | 451 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Warm-water coral reefs are very sensitive to global warming and ocean acidification. Coral reefs provide a habitat for thousands of species. They provide ecosystem services such as coastal protection and food. But 70–90% of today's warm-water coral reefs will disappear even if warming is kept to . Coral reefs are frame... | Effects of climate change | Wikipedia | 455 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Health, food security and water security
Humans have a climate niche. This is a certain range of temperatures in which they flourish. Outside that niche, conditions are less favourable. This leads to negative effects on health, food security and more. This niche is a mean annual temperature below 29 °C. As of May 2023... | Effects of climate change | Wikipedia | 502 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Between 1.5 and 2.5 billion people live in areas with regular water security issues. If global warming reaches , water insecurity would affect about twice as many people. Water resources are likely to decrease in most dry subtropical regions and mid-latitudes. But they will increase in high latitudes. However, variable... | Effects of climate change | Wikipedia | 470 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Low-lying coastal regions
Low-lying cities and other settlements near the sea face multiple simultaneous risks from climate change. They face flooding risks from sea level rise. In addition they may face impacts from more severe storms, ocean acidification, and salt intrusion into the groundwater. Changes like contin... | Effects of climate change | Wikipedia | 477 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Displacement is when people move within a country. Migration is when they move to another country. Some people use the terms interchangeably. Climate change affects displacement in several ways. More frequent and severe weather-related disasters may increase involuntary displacement. These destroy homes and habitats. C... | Effects of climate change | Wikipedia | 466 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Research has shown that climate change is not the most important conflict driver, and that it can only affect conflict risks under certain circumstances. Relevant context factors include agricultural dependence, a history of political instability, poverty, and the political exclusion of ethnic groups. Climate change ha... | Effects of climate change | Wikipedia | 426 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Climate change has long been described as a severe risk to humans. Climate change as an existential threat has emerged as a key theme in the climate movement. People from small island nations also use this theme. There has not been extensive research in this topic. Existential risks are threats that could cause the ext... | Effects of climate change | Wikipedia | 345 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Economic impacts are bigger the more the temperature rises. Scientists have compared impacts with warming of 1.5 °C (2.7 °F) and a level of 3.66 °C (6.59 °F). They use this higher figure to represent no efforts to stop emissions. They found that total damages at 1.5 °C were 90% less than at 3.66 °C. One study found tha... | Effects of climate change | Wikipedia | 439 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Highly affected sectors
Climate change has a bigger impact on economic sectors directly affected by weather than on other sectors. It heavily affects agriculture, fisheries and forestry. It also affects the tourism and energy sectors. Agriculture and forestry have suffered economic losses due to droughts and extreme h... | Effects of climate change | Wikipedia | 374 | 2119174 | https://en.wikipedia.org/wiki/Effects%20of%20climate%20change | Physical sciences | Climate change | Earth science |
Climate change mitigation (or decarbonisation) is action to limit the greenhouse gases in the atmosphere that cause climate change. Climate change mitigation actions include conserving energy and replacing fossil fuels with clean energy sources. Secondary mitigation strategies include changes to land use and removing c... | Climate change mitigation | Wikipedia | 421 | 2119179 | https://en.wikipedia.org/wiki/Climate%20change%20mitigation | Physical sciences | Climate change | Earth science |
Various policies can encourage climate change mitigation. Carbon pricing systems have been set up that either tax emissions or cap total emissions and trade emission credits. Fossil fuel subsidies can be eliminated in favor of clean energy subsidies, and incentives offered for installing energy efficiency measures or ... | Climate change mitigation | Wikipedia | 479 | 2119179 | https://en.wikipedia.org/wiki/Climate%20change%20mitigation | Physical sciences | Climate change | Earth science |
Electricity generation and transport are major emitters. The largest single source is coal-fired power stations with 20% of greenhouse gas emissions. Deforestation and other changes in land use also emit carbon dioxide and methane. The largest sources of anthropogenic methane emissions are agriculture, and gas venting ... | Climate change mitigation | Wikipedia | 511 | 2119179 | https://en.wikipedia.org/wiki/Climate%20change%20mitigation | Physical sciences | Climate change | Earth science |
In 2022, the Intergovernmental Panel on Climate Change (IPCC) released its Sixth Assessment Report on climate change. It warned that greenhouse gas emissions must peak before 2025 at the latest and decline 43% by 2030 to have a good chance of limiting global warming to 1.5 °C (2.7 °F). Or in the words of Secretary-Gene... | Climate change mitigation | Wikipedia | 445 | 2119179 | https://en.wikipedia.org/wiki/Climate%20change%20mitigation | Physical sciences | Climate change | Earth science |
The energy system includes the delivery and use of energy. It is the main emitter of carbon dioxide (). Rapid and deep reductions in the carbon dioxide and other greenhouse gas emissions from the energy sector are necessary to limit global warming to well below 2 °C. IPCC recommendations include reducing fossil fuel co... | Climate change mitigation | Wikipedia | 438 | 2119179 | https://en.wikipedia.org/wiki/Climate%20change%20mitigation | Physical sciences | Climate change | Earth science |
Other renewables
Other well-established renewable energy forms include hydropower, bioenergy and geothermal energy.
Hydroelectricity is electricity generated by hydropower and plays a leading role in countries like Brazil, Norway and China. but there are geographical limits and environmental issues. Tidal power can b... | Climate change mitigation | Wikipedia | 500 | 2119179 | https://en.wikipedia.org/wiki/Climate%20change%20mitigation | Physical sciences | Climate change | Earth science |
Nuclear power could complement renewables for electricity. On the other hand, environmental and security risks could outweigh the benefits.
The construction of new nuclear reactors currently takes about 10 years. This is much longer than scaling up the deployment of wind and solar. And this timing gives rise to credit... | Climate change mitigation | Wikipedia | 434 | 2119179 | https://en.wikipedia.org/wiki/Climate%20change%20mitigation | Physical sciences | Climate change | Earth science |
Global primary energy demand exceeded 161,000 terawatt hours (TWh) in 2018. This refers to electricity, transport and heating including all losses. In transport and electricity production, fossil fuel usage has a low efficiency of less than 50%. Large amounts of heat in power plants and in motors of vehicles go to wast... | Climate change mitigation | Wikipedia | 489 | 2119179 | https://en.wikipedia.org/wiki/Climate%20change%20mitigation | Physical sciences | Climate change | Earth science |
Some scientists say that avoiding meat and dairy foods is the single biggest way an individual can reduce their environmental impact. The widespread adoption of a vegetarian diet could cut food-related greenhouse gas emissions by 63% by 2050. China introduced new dietary guidelines in 2016 which aim to cut meat consump... | Climate change mitigation | Wikipedia | 484 | 2119179 | https://en.wikipedia.org/wiki/Climate%20change%20mitigation | Physical sciences | Climate change | Earth science |
To enhance the ability of ecosystems to sequester carbon, changes are necessary in agriculture and forestry. Examples are preventing deforestation and restoring natural ecosystems by reforestation. Scenarios that limit global warming to 1.5 °C typically project the large-scale use of carbon dioxide removal methods over... | Climate change mitigation | Wikipedia | 443 | 2119179 | https://en.wikipedia.org/wiki/Climate%20change%20mitigation | Physical sciences | Climate change | Earth science |
Afforestation is the establishment of trees where there was previously no tree cover. Scenarios for new plantations covering up to 4000 million hectares (Mha) (6300 x 6300 km) suggest cumulative carbon storage of more than 900 GtC (2300 Gt) until 2100. But they are not a viable alternative to aggressive emissions reduc... | Climate change mitigation | Wikipedia | 497 | 2119179 | https://en.wikipedia.org/wiki/Climate%20change%20mitigation | Physical sciences | Climate change | Earth science |
There are many measures to increase soil carbon. This makes it complex and hard to measure and account for. One advantage is that there are fewer trade-offs for these measures than for BECCS or afforestation, for example.
Globally, protecting healthy soils and restoring the soil carbon sponge could remove 7.6 billion ... | Climate change mitigation | Wikipedia | 456 | 2119179 | https://en.wikipedia.org/wiki/Climate%20change%20mitigation | Physical sciences | Climate change | Earth science |
Some wetlands are a significant source of methane emissions. Some also emit nitrous oxide. Peatland globally covers just 3% of the land's surface. But it stores up to 550 gigatonnes (Gt) of carbon. This represents 42% of all soil carbon and exceeds the carbon stored in all other vegetation types, including the world's ... | Climate change mitigation | Wikipedia | 422 | 2119179 | https://en.wikipedia.org/wiki/Climate%20change%20mitigation | Physical sciences | Climate change | Earth science |
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