Genus ( / ˈ dʒ iː n ə s / ; pl. : genera / ˈ dʒ ɛ n ər ə / ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses . In binomial nomenclature , the genus name forms the first part of the binomial species name for each species within the genus.
111-558: Centaurea ( / ˌ s ɛ n t ɔː ˈ r iː ə / ) is a genus of over 700 species of herbaceous thistle -like flowering plants in the family Asteraceae . Members of the genus are found only north of the equator, mostly in the Eastern Hemisphere; the Middle East and surrounding regions are particularly species-rich. Common names for this genus are centaury , centory , starthistles , knapweeds , centaureas and
222-452: A bitter compound found mainly in the leaves and often used to flavor the digestif amaro . In western Crete , Greece a local variety of C. calcitrapa called gourounaki ( γουρουνάκι "little pig") also has its leaves eaten boiled by the locals. In the same island an endemic local species, C. idaea called katsoula ( κατσούλα ), tsita ( τσίτα ) or aspragatha ( ασπραγκάθα ), has its leaves eaten boiled by
333-440: A wheelwright , would cause the tire to expand by heating it in a forge fire, placing it over the wheel, and quenching it, causing the metal to contract back to its original size to fit tightly on the wheel. The first patent for what appears to be a standard pneumatic tire appeared in 1847 and was lodged by Scottish inventor Robert William Thomson . However, this idea never went into production. The first practical pneumatic tire
444-494: A 1968 article in an influential American magazine, Consumer Reports , highlighting the superiority of radial construction. The US tire industry lost its market share to Japanese and European manufacturers, which bought out US companies. Tires may be classified according to the type of vehicle they serve. They may be distinguished by the load they carry and by their application, e.g. to a motor vehicle, aircraft, or bicycle. Light-duty tires for passenger vehicles carry loads in
555-633: A bias tire are many, including longer tread life, better steering control, lower rolling resistance , improved fuel economy, more uniform wear, higher heat resistance, fewer blowouts, and a steadier, more comfortable ride at speed. Disadvantages, besides a higher cost than that of bias tires, are a harder ride at low speeds and generally worse performance on rough terrain. Radial tires are also seldom seen in diameters of greater than 42 inches, as such tires are difficult to make. Bias tire (bias-ply, or cross-ply) construction utilizes body ply cords that extend diagonally from bead to bead, usually at angles in
666-715: A comparatively long duration, many species of Centaurea are popular food sources for insects that may otherwise attack certain crops . It may be advisable for some types of farms to allow certain Centaurea species, such as cornflower ( C. cyanus ) in a European setting, to grow adjacent to fields. These areas are known as beetle banks , though they support and attract a diversity of beneficial life beyond beetles. When certain Centaurea species are present, some pests may be drawn away from crops, and predatory insects and arachnids that feed upon pest insects will be better-supported by these more naturalized areas. They additionally have
777-407: A genus is determined by taxonomists . The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: Moreover, genera should be composed of phylogenetic units of
888-462: A host plant for the black swallowtail butterfly, helps to bring nutrients up from soils with its deep taproot, and possesses evergreen foliage even in climate zones such as US zone 6. This foliage increases soil warmth and moisture which can be beneficial for certain types of life. Perhaps the most dramatic example of a generally disliked plant's beneficial qualities being usually overlooked is the often-despised ragwort, Jacobaea vulgaris , which topped
999-651: A later homonym of a validly published name is a nomen illegitimum or nom. illeg. ; for a full list refer to the International Code of Nomenclature for algae, fungi, and plants and the work cited above by Hawksworth, 2010. In place of the "valid taxon" in zoology, the nearest equivalent in botany is " correct name " or "current name" which can, again, differ or change with alternative taxonomic treatments or new information that results in previously accepted genera being combined or split. Prokaryote and virus codes of nomenclature also exist which serve as
1110-544: A lesser extentely diffuse knapweed, sometimes killing off the entire plant. Also used in biological control are Tephritidae (peacock flies) whose larvae feed on Centaurea . Knapweed peacock fly ( Chaetorellia acrolophi ) larvae eat spotted knapweed and some other species. The yellow starthistle peacock fly ( C. australis ) has an initial generation each year which often uses cornflower ( C. cyanus ) as larval food; later generations switch to yellow starthistle. The flies are generally considered less efficient in destroying
1221-628: A long time and redescribed as new by a range of subsequent workers, or if a range of genera previously considered separate taxa have subsequently been consolidated into one. For example, the World Register of Marine Species presently lists 8 genus-level synonyms for the sperm whale genus Physeter Linnaeus, 1758, and 13 for the bivalve genus Pecten O.F. Müller, 1776. Within the same kingdom, one generic name can apply to one genus only. However, many names have been assigned (usually unintentionally) to two or more different genera. For example,
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#17328014491691332-409: A reference for designating currently accepted genus names as opposed to others which may be either reduced to synonymy, or, in the case of prokaryotes, relegated to a status of "names without standing in prokaryotic nomenclature". An available (zoological) or validly published (botanical) name that has been historically applied to a genus but is not regarded as the accepted (current/valid) name for
1443-479: A separate inner tube . Semi-pneumatic tires have a hollow center, but they are not pressurized. They are lightweight, low-cost, puncture-proof, and provide cushioning. These tires often come as a complete assembly with the wheel and even integral ball bearings . They are used on lawn mowers , wheelchairs , and wheelbarrows . They can also be rugged, typically used in industrial applications, and are designed to not pull off their rim under use. An airless tire
1554-511: A spring ephemeral , as well as an annual that lacks difficult-to-combat roots. Plants that provide necessary structural supports for invertebrate and small vertebrate predators can help to keep overall pest populations low. The abundant nectar produced by C. solstitialis flowers attracts many pollinators . This is another reason for the success of the (situationally) highly invasive species . Due to genetic differences related to evolutionary adaption, not all members of Centaurea produce
1665-427: A taxon; however, the names published in suppressed works are made unavailable via the relevant Opinion dealing with the work in question. In botany, similar concepts exist but with different labels. The botanical equivalent of zoology's "available name" is a validly published name . An invalidly published name is a nomen invalidum or nom. inval. ; a rejected name is a nomen rejiciendum or nom. rej. ;
1776-524: A thin layer of brass, various additives will also be added to the rubber to improve binding, such as resorcinol / HMMM mixtures. The elastomer, which forms the tread and encases the cords to protect them from abrasion and hold them in place, is a key component of pneumatic tire design. It can be composed of various composites of rubber material – the most common being styrene-butadiene copolymer – with other chemical compounds such as silica and carbon black . Optimizing rolling resistance in
1887-455: A total of c. 520,000 published names (including synonyms) as at end 2019, increasing at some 2,500 published generic names per year. "Official" registers of taxon names at all ranks, including genera, exist for a few groups only such as viruses and prokaryotes, while for others there are compendia with no "official" standing such as Index Fungorum for fungi, Index Nominum Algarum and AlgaeBase for algae, Index Nominum Genericorum and
1998-507: A variety of profiles and carry loads in the range of 4,000 to 5,500 pounds (1,800 to 2,500 kg) on the drive wheel. These are typically mounted in tandem on the drive axle. Aircraft, bicycles, and a variety of industrial applications have distinct design requirements. Tire construction spans pneumatic tires used on cars, trucks, and aircraft, but also includes non-automotive applications with slow-moving, light-duty, or railroad applications, which may have non-pneumatic tires. Following
2109-687: A whole, providing the main advantage of this construction, better traction and smoother motion on uneven surfaces, with a greater tendency to conform to rocky ground and throw off mud and clay, especially because the rubber is usually of a softer compound than that used on radial tires. However, this conformity increases a bias tire's rolling resistance, and its stiffness allows less control, traction , and comfort at higher speeds, while shear between its overlapping plies causes friction that generates heat. Still, bias tires benefit from simpler structure and so cost less than like-size radials, and they remain in use on heavy equipment and off-road vehicles, although
2220-557: Is a non-pneumatic tire that is not supported by air pressure. They are most commonly used on small vehicles, such as golf carts, and on utility vehicles in situations where the risk of puncture is high, such as on construction equipment. Many tires used in industrial and commercial applications are non-pneumatic, and are manufactured from solid rubber and plastic compounds via molding operations. Solid tires include those used for lawnmowers, skateboards, golf carts, scooters , and many types of light industrial vehicles, carts, and trailers. One of
2331-430: Is a term used for a tire that failed inspection during manufacturing - but only for superficial/cosmetic/aesthetic reasons. For example, a tire with white painted lettering which is smudged or incomplete might be classified as a "blem". Blem tires are fully functional and generally carry the same warranty as flawless tires - but are sold at a discount. The materials of modern pneumatic tires can be divided into two groups,
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#17328014491692442-505: Is almost extinct , while the western Caucasus endemics C. leptophylla and C. straminicephala are at least very rare and C. hedgei and C. pecho from the same region are certainly not abundant either. The last four species would be adversely affected by the proposed Yusufeli Dam , which might actually destroy enough habitat to push the two rarer ones over the brink of extinction. Centaurea are copious nectar producers, especially on high-lime soils . The high nectar yield of
2553-402: Is also the national flower of Estonia where its local name rukkilill means "rye- lily ", Belarus where it is called vałoška ( Belarusian : валошка ), and one of those of Germany where it is called Kornblume ("cornflower"). The origin of the name " caltrop " for the ancient low-tech area denial weapon is probably in some way connected with C. calcitrapa and its spiny seeds. This plant
2664-694: Is attested to by the colloquial name "caltrop" at a time when the weapons were still called by their Roman name tribulus . Lastly, the color cornflower blue is named after C. cyanus . Cornflower is also used as a cut flower. As namesake member of the subtribe Centaureinae of tribe Cardueae , the knapweeds are probably most closely related to genera such as Carthamus (distaff thistles), Cnicus (blessed thistle), Crupina (crupinas) or Notobasis (Syrian thistle), and somewhat less closely to most other thistles . The monotypic Cnicus seems in fact to properly belong in Centaurea . Research in
2775-416: Is characterized by a system of circumferential grooves, lateral sipes, and slots for road tires or a system of lugs and voids for tires designed for soft terrain or snow. Grooves run circumferentially around the tire and are needed to channel away water. Lugs are that portion of the tread design that contacts the road surface. Grooves, sipes, and slots allow tires to evacuate water. The design of treads and
2886-426: Is constructed with robust steel cables encased in durable, specially formulated rubber designed to resist stretching. The precision of the bead's fit is crucial, as it seals the tire against the wheel, maintaining air pressure integrity and preventing any loss of air. The bead's design ensures a secure, non-slip connection, preventing the tire from rotating independently from the wheel during vehicle motion. Additionally,
2997-612: Is discouraged by both the International Code of Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants , there are some five thousand such names in use in more than one kingdom. For instance, A list of generic homonyms (with their authorities), including both available (validly published) and selected unavailable names, has been compiled by the Interim Register of Marine and Nonmarine Genera (IRMNG). The type genus forms
3108-513: Is even fraudulently relabeled and sold as the scarce and expensive sourwood honey of the Appalachian Mountains . Placing beehives near stands of Centaurea will cause increased pollination. As most seedheads fail however when biocontrol pests have established themselves, the plants will bloom ever more abundantly in an attempt to replace the destroyed seedheads, to the point where they exhaust their resources in providing food for
3219-590: Is found much more rarely by comparison, often in association with red fescue ( Festuca rubra ) in addition to cock's-foot and false oat-grass. Due to their habit of dominating ecosystems under good conditions, many Centaurea species can become invasive weeds in regions where they are not native. In parts of North America, diffuse knapweed ( C. diffusa ), spotted knapweed ( C. maculosa ) and yellow starthistle ( C. solstitialis ) cause severe problems in agriculture due to their uncontrolled spread. The seeds are typically transported by human traffic, in particular
3330-527: Is key in achieving safety and fuel efficiency in the transportation sector. The most common elastomer material used today is a styrene - butadiene copolymer. It combines the properties of polybutadiene , which is a highly rubbery polymer ( Tg = -100 °C) having high hysteresis and thus offering good wet grip properties, with the properties of polystyrene , which is a glassy polymer ( Tg = 100 °C) having low hysteresis and thus offering low rolling resistance in addition to wear resistance. Therefore,
3441-588: Is most prominently found in pastures or meadows dominated by cock's-foot ( Dactylis glomerata ) as well as either of crested dog's-tail ( Cynosurus cristatus ) and false oat-grass ( Arrhenatherum elatius ). It is also often found in mesotrophic grassland on rendzinas and similar calcareous soils in association with glaucous sedge ( Carex flacca ), sheep's fescue ( Festuca ovina ), and either tor-grass ( Brachypodium pinnatum ) and rough hawkbit ( Leontodon hispidus ), or upright brome ( Bromus erectus ). In these grasslands , greater knapweed ( C. scabiosa )
Centaurea - Misplaced Pages Continue
3552-617: Is not now accepted by the best English authorities, and is unrecognized in the US" , while Fowler's Modern English Usage of 1926 describes that "there is nothing to be said for 'tyre', which is etymologically wrong, as well as needlessly divergent from our own [sc. British] older & the present American usage". However, over the 20th century, tyre became established as the standard British spelling. The earliest tires were bands of leather , then iron (later steel ) placed on wooden wheels used on carts and wagons . A skilled worker, known as
3663-428: Is sometimes used, although this also refers to the unrelated plant genus Centaurium . The name is said to be in reference to Chiron , the centaur of Greek mythology who discovered medicinal uses of a plant eventually called "centaury". Knapweeds are robust weedy plants. Their leaves, spiny in some species, are usually deeply divided into elongated lobes at least in the plants' lower part, becoming entire towards
3774-460: Is somewhat arbitrary. Although all species within a genus are supposed to be "similar", there are no objective criteria for grouping species into genera. There is much debate among zoologists about whether enormous, species-rich genera should be maintained, as it is extremely difficult to come up with identification keys or even character sets that distinguish all species. Hence, many taxonomists argue in favor of breaking down large genera. For instance,
3885-437: Is that part of the tire at the edge of the tread as it makes the transition to the sidewall. Plies are layers of relatively inextensible cords embedded in the rubber to hold its shape by preventing the rubber from stretching in response to the internal pressure. The orientations of the plies play a large role in the performance of the tire and are one of the main ways that tires are categorized. Blem (short for "blemished")
3996-474: Is the type species , and the generic name is permanently associated with the type specimen of its type species. Should the specimen turn out to be assignable to another genus, the generic name linked to it becomes a junior synonym and the remaining taxa in the former genus need to be reassessed. In zoological usage, taxonomic names, including those of genera, are classified as "available" or "unavailable". Available names are those published in accordance with
4107-621: The International Code of Zoological Nomenclature ; the earliest such name for any taxon (for example, a genus) should then be selected as the " valid " (i.e., current or accepted) name for the taxon in question. Consequently, there will be more available names than valid names at any point in time; which names are currently in use depending on the judgement of taxonomists in either combining taxa described under multiple names, or splitting taxa which may bring available names previously treated as synonyms back into use. "Unavailable" names in zoology comprise names that either were not published according to
4218-824: The International Plant Names Index for plants in general, and ferns through angiosperms, respectively, and Nomenclator Zoologicus and the Index to Organism Names for zoological names. Totals for both "all names" and estimates for "accepted names" as held in the Interim Register of Marine and Nonmarine Genera (IRMNG) are broken down further in the publication by Rees et al., 2020 cited above. The accepted names estimates are as follows, broken down by kingdom: The cited ranges of uncertainty arise because IRMNG lists "uncertain" names (not researched therein) in addition to known "accepted" names;
4329-419: The nomenclature codes , which allow each species a single unique name that, for animals (including protists ), plants (also including algae and fungi ) and prokaryotes ( bacteria and archaea ), is Latin and binomial in form; this contrasts with common or vernacular names , which are non-standardized, can be non-unique, and typically also vary by country and language of usage. Except for viruses ,
4440-404: The platypus belongs to the genus Ornithorhynchus although George Shaw named it Platypus in 1799 (these two names are thus synonyms ) . However, the name Platypus had already been given to a group of ambrosia beetles by Johann Friedrich Wilhelm Herbst in 1793. A name that means two different things is a homonym . Since beetles and platypuses are both members of the kingdom Animalia,
4551-772: The purple starthistle ( C. calcitrapa ) is traditionally consumed by ethnic Albanians ( Arbëreshë people ) in the Vulture area (southern Italy); e.g. in the Arbëreshë communities in Lucania the young whorls of C. calcitrapa are boiled and fried in mixtures with other weedy non-cultivated greens. According to research by the Michael Heinrich group at the Centre for Pharmacognosy and Phytotherapy ( School of Pharmacy, University of London ) "the antioxidant activity [...] of
Centaurea - Misplaced Pages Continue
4662-479: The radial tire method of construction. Michelin had bought the bankrupt Citroën automobile company in 1934 to utilize this new technology. Because of its superiority in handling and fuel economy, use of this technology quickly spread throughout Europe and Asia. In the US, the outdated bias-ply tire construction persisted until the Ford Motor Company adopted radial tires in the early 1970s, following
4773-638: The subfamily Lixinae also feed on Centaurea . Some genera – such as Larinus whose larval food is flowerheads – have many species especially adapted to particular knapweeds or starthistle and are used in biological control too. These include the yellow starthistle flower weevil ( L. curtus ) for yellow starthistle, lesser knapweed flower weevil ( L. minutus ) for diffuse knapweed and blunt knapweed flower weevil ( L. obtusus ) for spotted knapweed. Broad-nosed seedhead weevil ( Bangasternus fausti ) larvae eat diffuse, spotted and squarrose knapweed ( C. virgata ssp. squarrosa ), while those of
4884-668: The taxonomic consequences of a rearrangement might be severe, with hundreds of species needing to be moved to new genera. It has thus been proposed to change the type species to one of the main lineages to avoid this problem. What seems certain however is that the basketflowers – presently treated as a section Plectocephalus – will be reinstated as a distinct genus in the near future. The rock-centauries ( Cheirolophus ), formerly usually included in Centaurea , are now already treated as separate genus. Better-known Centaurea species include: Plant species formerly placed in Centaurea include: Genus The composition of
4995-482: The tires of all-terrain vehicles . The two knapweeds are harmful mainly because they are strongly allelopathic , producing powerful toxins in their roots that stunt the growth of plants around them not adapted to this. Yellow starthistle, meanwhile, is inedible to most livestock due to its spines and apparently outright poisonous to horses and other equines . However, efficient methods of biological control by insect pests of these weeds have been developed;
5106-529: The vulcanization of natural rubber using sulfur, as well as the development of the "clincher" rim for holding the tire in place laterally on the wheel rim. Synthetic rubbers were invented in the laboratories of Bayer in the 1920s. Rubber shortages in the United Kingdom during WWII prompted research on alternatives to rubber tires with suggestions including leather, compressed asbestos, rayon, felt, bristles, and paper. In 1946, Michelin developed
5217-425: The yellow starthistle bud weevil ( B. orientalis ) do not seem to live on anything other than yellow starthistle and occasionally purple starthistle ( C. calcitrapa ). But perhaps most efficient in destroying developing yellow starthistle seedheads is the larva of the yellow starthistle hairy weevil ( Eustenopus villosus ). Knapweed root weevil ( Cyphocleonus achates ) larvae bore into the roots of spotted and to
5328-420: The " Polyglas " trademark tire featuring a polyester carcass with belts of fiberglass. The "belted" tire starts two main plies of polyester, rayon, or nylon annealed as in conventional tires, and then placed on top are circumferential belts at different angles that improve performance compared to non-belted bias tires. The belts may be fiberglass or steel. Tubeless tires are pneumatic tires that do not require
5439-630: The 1840s when the English began shrink-fitting railway car wheels with malleable iron. Nevertheless, many publishers continued using tire . The Times newspaper in London was still using tire as late as 1905. The spelling tyre began to be commonly used in the 19th century for pneumatic tires in the UK. The 1911 edition of the Encyclopædia Britannica states that "The spelling 'tyre'
5550-479: The 1968 Consumer Reports announcement of the superiority of the radial design, radial tires began an inexorable climb in market share, reaching 100% of the North American market in the 1980s. Radial tire technology is now the standard design for essentially all automotive tires, but other methods have been used. Radial (or radial-ply) tire construction utilizes body ply cords extending straight across
5661-442: The base for higher taxonomic ranks, such as the family name Canidae ("Canids") based on Canis . However, this does not typically ascend more than one or two levels: the order to which dogs and wolves belong is Carnivora ("Carnivores"). The numbers of either accepted, or all published genus names is not known precisely; Rees et al., 2020 estimate that approximately 310,000 accepted names (valid taxa) may exist, out of
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#17328014491695772-415: The beneficial aspect of supporting pollinators , unlike many field crops such as maize . Moreover, being untreated with pesticides and providing more diversity , plants growing in more wild areas adjacent to farms produce more insects that attract and support birds which can also feed on pests that would harm crops. Insect production is especially high for beetle banks that have enough plants that serve in
5883-408: The bottom of the tread grooves that indicate the tire has reached its wear limit. When the tread lugs are worn to the point that the wear bars connect across the lugs, the tires are fully worn and should be taken out of service, typically at a remaining tread depth of 1.6 millimetres (0.063 in). The tire bead is the part of the tire that contacts the rim on the wheel. This essential component
5994-416: The cords that make up the ply and the elastomer which encases them. The cords, which form the ply and bead and provide the tensile strength necessary to contain the inflation pressure, can be composed of steel , natural fibers such as cotton or silk , or synthetic fibers such as nylon or kevlar . Good adhesion between the cords and the rubber is important. To achieve this the steel cords are coated in
6105-401: The earthmoving market has shifted to radials. A belted bias tire starts with two or more bias plies to which stabilizer belts are bonded directly beneath the tread. This construction provides a smoother ride that is similar to the bias tire, while lessening rolling resistance because the belts increase tread stiffness. The design was introduced by Armstrong, while Goodyear made it popular with
6216-421: The elastomer material is a key challenge for reducing fuel consumption in the transportation sector. It is estimated that passenger vehicles consume approximately 5~15% of their fuel to overcome rolling resistance, while the estimate is understood to be higher for heavy trucks. However, there is a trade-off between rolling resistance and wet traction and grip: while low rolling resistance can be achieved by reducing
6327-503: The environment. Moreover, the regular use of tires produces micro-plastic particles that contain these chemicals that both enter the environment and affect human health. The word tire is a short form of attire , from the idea that a wheel with a tire is a dressed wheel. Tyre is the oldest spelling, and both tyre and tire were used during the 15th and 16th centuries. During the 17th and 18th centuries, tire became more common in print. The spelling tyre did not reappear until
6438-487: The first pneumatic tires. Cyclist Willie Hume demonstrated the supremacy of Dunlop's tires in 1889, winning the tire's first-ever races in Ireland and then England. In Dunlop's tire patent specification dated 31 October 1888, his interest is only in its use in cycles and light vehicles. In September 1890, he was made aware of an earlier development, but the company kept the information to itself. In 1892, Dunlop's patent
6549-446: The form "author, year" in zoology, and "standard abbreviated author name" in botany. Thus in the examples above, the genus Canis would be cited in full as " Canis Linnaeus, 1758" (zoological usage), while Hibiscus , also first established by Linnaeus but in 1753, is simply " Hibiscus L." (botanical usage). Each genus should have a designated type , although in practice there is a backlog of older names without one. In zoology, this
6660-737: The generic name (or its abbreviated form) still forms the leading portion of the scientific name, for example, Canis lupus lupus for the Eurasian wolf subspecies, or as a botanical example, Hibiscus arnottianus ssp. immaculatus . Also, as visible in the above examples, the Latinised portions of the scientific names of genera and their included species (and infraspecies, where applicable) are, by convention, written in italics . The scientific names of virus species are descriptive, not binomial in form, and may or may not incorporate an indication of their containing genus; for example,
6771-484: The genus can be exploited to the farmer's advantage, possibly in combination with biological control . In particular, the yellow starthistle ( C. solstitialis ) as well as spotted knapweed ( C. maculosa ) are major honey plants for beekeepers . Monofloral honey from these plants is light and slightly tangy, and one of the finest honeys produced in the United States – due to its better availability, it
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#17328014491696882-606: The genus makes it very attractive to insects such as butterflies – including the endangered Karner blue ( Plebejus melissa samuelis ) which visits introduced spotted knapweed – and day-flying moths – typically Zygaenidae , such as Zygaena loti or the six-spot burnet ( Z. filipendulae ). The larvae of some other Lepidoptera species use Centaurea species as food plants; see List of Lepidoptera that feed on Centaurea . Several of these are used in biological control of invasive knapweeds and starthistles. Larvae of several true weevils (Curculionidae) of
6993-436: The global automotive tire market indicate continued growth through 2027. Estimates put the value of worldwide sales volume around $ 126 billion in 2022, it is expected to reach the value of over $ 176 billion by 2027. Production of tires is also experiencing growth. In 2015, the US manufactured almost 170 million tires. Over 2.5 billion tires are manufactured annually, making the tire industry a major consumer of natural rubber. It
7104-419: The grooves, which allow the water from the grooves to escape sideways and mitigate hydroplaning . Different tread designs address a variety of driving conditions. As the ratio of tire tread area to groove area increases, so does tire friction on dry pavement, as seen on Formula One tires , some of which have no grooves. High-performance tires often have smaller void areas to provide more rubber in contact with
7215-434: The growing seedheads than the weevils, but may be superior under certain conditions; employing flies and weevils in combination is expensive and does not noticeably increase their effect. Despite the negative agricultural and environmental impacts of the more aggressive Centaurea species, there are many ways in which they benefit humans as well. For instance, due to their moderate to high nectar production, which can occur over
7326-408: The interaction of specific tire types with the roadway surface affects roadway noise , a source of noise pollution emanating from moving vehicles. These sound intensities increase with higher vehicle speeds. Tires treads may incorporate a variety of distances between slots ( pitch lengths ) to minimize noise levels at discrete frequencies. Sipes are slits cut across the tire, usually perpendicular to
7437-495: The interplay between the bead's dimensions and the wheel's width significantly influences the vehicle's steering responsiveness and stability, as it helps to maintain the tire’s intended shape and contact with the road. The sidewall is that part of the tire, or bicycle tire , that bridges between the tread and bead. The sidewall is largely rubber but reinforced with fabric or steel cords that provide for tensile strength and flexibility. The sidewall contains air pressure and transmits
7548-560: The knapweed and are little harmed if at all, aided by native microorganisms that break down or even feed on the abundantly secreted compound. Thus, 8-hydroxyquinoline is potentially useful to control American plants that have become invasive weeds in the diffuse knapweed's native range. Arctiin, found in C. imperialis , has shown anticancer activity in laboratory studies. The roots of the long-lost C. foliosa , an endemic of Hatay Province (Turkey), are used in folk medicine, and other species are presumably too. A South Italian variety of
7659-564: The knapweeds can also exploited to their detriment by targeted grazing . Controlled burning may also be used, though the timing is important to avoid the plants having seeded already, and neither allowing sufficient time for them to regrow from the rootstock. Yet other species of Centaurea – mostly ones that occur between Italy and the Caucasus – are endemics of a single island or valley, and some of these are endangered . The Akamas Centaurea ( Centaurea akamantis ) of Cyprus
7770-633: The largest component, with 23,236 ± 5,379 accepted genus names, of which 20,845 ± 4,494 are angiosperms (superclass Angiospermae). By comparison, the 2018 annual edition of the Catalogue of Life (estimated >90% complete, for extant species in the main) contains currently 175,363 "accepted" genus names for 1,744,204 living and 59,284 extinct species, also including genus names only (no species) for some groups. The number of species in genera varies considerably among taxonomic groups. For instance, among (non-avian) reptiles , which have about 1180 genera,
7881-415: The late 20th century shows that Centaurea as traditionally defined is polyphyletic . A number of 19th- and 20th-century efforts to reorganize the genus were not successful, and it is not yet clear what the consequences of the recent research will be for classification of this genus and other related genera. The type species C. centaurium stands somewhat apart from the main lineage of knapweeds and thus
7992-401: The list by a large amount for nectar production in a UK study, with a production per floral unit of (2921 ± 448μg). This very high nectar production, coupled with its early blooming period, makes the plant helpful for the establishment of bee colonies in spring — a period that is often not well-served by commercial flower meadow seed mixes. It also has the situationally-beneficial quality of being
8103-411: The lizard genus Anolis has been suggested to be broken down into 8 or so different genera which would bring its ~400 species to smaller, more manageable subsets. Tire A tire ( British spelling : tyre ) is a ring-shaped component that surrounds a wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide traction on the surface over which
8214-506: The locals too. Cornflower blue #6495ED Some species are cultivated as ornamental plants in gardens . As regards other aspects of popular culture , cornflower ( C. cyanus ) is the floral emblem of Östergötland province (Sweden) – where is it called blåklint , literally "blue mountain" – and of Päijänne Tavastia region in Finland , where it is known as ruiskaunokki (" rye -beaks") or ruiskukka ("rye-flower"). It
8325-484: The more aggressive species. An example is wild parsnip, Pastinaca sativa , which produces florets that feed predatory (and other beneficial) insects as well as large tubular stems that provide winter shelter for native bees, wasps, and other organisms that can be beneficial for agriculture. The plant is considered invasive in some areas of the United States and is also often considered undesirable due to its ability to cause contact skin irritation. However, it also serves as
8436-441: The more ambiguous " bluets "; a vernacular name used for these plants in parts of England is " loggerheads " ( common knapweed ). The Plectocephalus group – possibly a distinct genus – is known as basketflowers . "Cornflower" is used for a few species, but that term more often specifically means either C. cyanus (the annual cornflower) or Centaurea montana (the perennial cornflower). The common name " centaury "
8547-403: The most (>300) have only 1 species, ~360 have between 2 and 4 species, 260 have 5–10 species, ~200 have 11–50 species, and only 27 genera have more than 50 species. However, some insect genera such as the bee genera Lasioglossum and Andrena have over 1000 species each. The largest flowering plant genus, Astragalus , contains over 3,000 species. Which species are assigned to a genus
8658-458: The most common applications for solid tires is for material handling equipment (forklifts). Such tires are installed utilizing a hydraulic tire press. Wooden wheels for horse-drawn vehicles usually have a wrought iron tire. This construction was extended to wagons on horse-drawn tramways, rolling on granite setts or cast iron rails . The wheels of some railway engines and older types of rolling stock are fitted with railway tires to prevent
8769-434: The name "basketflowers". Many species, in particular those inhabiting more arid regions, have a long and strong taproot . Certain knapweeds have a tendency to dominate large stretches of landscape together with a few other plants, typically one or two grasses and as many other large herbaceous plants. The common knapweed ( C. nigra ) for example is plentiful in the mesotrophic grasslands of England and nearby regions. It
8880-428: The name could not be used for both. Johann Friedrich Blumenbach published the replacement name Ornithorhynchus in 1800. However, a genus in one kingdom is allowed to bear a scientific name that is in use as a generic name (or the name of a taxon in another rank) in a kingdom that is governed by a different nomenclature code. Names with the same form but applying to different taxa are called "homonyms". Although this
8991-423: The need to replace the entirety of a wheel. The tire, usually made of steel, surrounds the wheel and is primarily held in place by interference fit . Aircraft tires may operate at pressures that exceed 200 pounds per square inch (14 bar ; 1,400 kPa ). Some aircraft tires are inflated with nitrogen to "eliminate the possibility of a chemical reaction between atmospheric oxygen and volatile gases from
9102-453: The non-spiny knapweeds with relish. In Europe, common knapweed ( C. nigra ) and globe knapweed ( C. macrocephala ) are locally important pollen sources for honeybees in mid-late summer. 8-Hydroxyquinoline has been identified as a main allelopathic compound produced by diffuse knapweed ( C. diffusa ); native North American plants are typically sensitive to it, while those of Eastern Europe and Asia Minor usually have coevolved with
9213-562: The pests (seeds), bees ( pollen ) and humans (honey). Output of allelopathic compounds is also liable to be reduced under such conditions – the plant has to compromise between allocating energy to reproduction and defense. This renders the weeds more likely to be suppressed by native vegetation or crops in the following years, especially if properly timed controlled burning and/or targeted grazing by suitable livestock are also employed. While yellow starthistle and perhaps other species are toxic to equines , some other livestock may eat
9324-541: The provisions of the ICZN Code, e.g., incorrect original or subsequent spellings, names published only in a thesis, and generic names published after 1930 with no type species indicated. According to "Glossary" section of the zoological Code, suppressed names (per published "Opinions" of the International Commission of Zoological Nomenclature) remain available but cannot be used as the valid name for
9435-402: The range of 30 to 40 degrees from the direction of travel. Successive plies are laid at opposing angles, forming a crisscross pattern to which the tread is applied. Such a design is resistant to sidewall deformation and punctures (and to punctures’ expansion, or “torque splitting”) and therefore durable in severe use. Since the tread and sidewalls share their casing plies, the tire body flexes as
9546-639: The range of 550 to 1,100 pounds (250 to 500 kg) on the drive wheel. Light-to-medium duty trucks and vans carry loads in the range of 1,100 to 3,300 pounds (500 to 1,500 kg) on the drive wheel. They are differentiated by speed rating for different vehicles, including (starting from the lowest speed to the highest): winter tires, light truck tires, entry-level car tires, sedans and vans, sport sedans, and high-performance cars. Apart from road tires, there are special categories: Other types of light-duty automotive tires include run-flat tires and race car tires: Heavy-duty tires for large trucks and buses come in
9657-530: The ratio of the two monomers in the styrene-butadiene copolymer is considered key in determining the glass transition temperature of the material, which is correlated to its grip and resistance properties. Non-exhaust emissions of particulate matter, generated by the wearing down of brakes, clutches, tires, and road surfaces, as well as by the suspension of road dust, constitute a little-known but rising share of emissions from road traffic and significantly harm public health. Associated components of tires include
9768-435: The road for higher traction, but may be compounded with softer rubber that provides better traction, but wears quickly. Mud and snow (M&S) tires employ larger and deeper slots to engage mud and snow. Snow tires have still larger and deeper slots that compact snow and create shear strength within the compacted snow to improve braking and cornering performance. Wear bars (or wear indicators) are raised features located at
9879-443: The role of host plant for immature insects, rather than just in the roles of adult food and/or shelter provision. Some plants which are considered invasive or problematic in certain areas can have beneficial qualities that outweigh their negative qualities from a human and/or human agricultural point of view, although this sometimes requires some human management – particularly if adequate biological control has not been established for
9990-450: The same amount of nectar. Growing conditions, such as climate and soil, can have a very strong impact, even if the plants grow and flower. For instance, cornflower plants, Centaurea cyanus , produced 33% less seasonal nectar than Centaurea nigra in a UK study. C. nigra also ranked higher than ragwort in another UK study, although ragwort was still in the top 10 for yearly nectar production. The strong nectar production of certain members of
10101-470: The same kind as other (analogous) genera. The term "genus" comes from Latin genus , a noun form cognate with gignere ('to bear; to give birth to'). The Swedish taxonomist Carl Linnaeus popularized its use in his 1753 Species Plantarum , but the French botanist Joseph Pitton de Tournefort (1656–1708) is considered "the founder of the modern concept of genera". The scientific name (or
10212-408: The scientific epithet) of a genus is also called the generic name ; in modern style guides and science, it is always capitalised. It plays a fundamental role in binomial nomenclature , the system of naming organisms , where it is combined with the scientific name of a species : see Botanical name and Specific name (zoology) . The rules for the scientific names of organisms are laid down in
10323-497: The specific name particular to the wolf. A botanical example would be Hibiscus arnottianus , a particular species of the genus Hibiscus native to Hawaii. The specific name is written in lower-case and may be followed by subspecies names in zoology or a variety of infraspecific names in botany . When the generic name is already known from context, it may be shortened to its initial letter, for example, C. lupus in place of Canis lupus . Where species are further subdivided,
10434-412: The standard format for a species name comprises the generic name, indicating the genus to which the species belongs, followed by the specific epithet, which (within that genus) is unique to the species. For example, the gray wolf 's scientific name is Canis lupus , with Canis ( Latin for 'dog') being the generic name shared by the wolf's close relatives and lupus (Latin for 'wolf') being
10545-403: The surface. The materials of modern pneumatic tires are synthetic rubber , natural rubber , fabric, and wire, along with carbon black and other chemical compounds. They consist of a tread and a body. The tread provides traction while the body provides containment for a quantity of compressed air . Before rubber was developed, tires were metal bands fitted around wooden wheels to hold
10656-403: The taxon is termed a synonym ; some authors also include unavailable names in lists of synonyms as well as available names, such as misspellings, names previously published without fulfilling all of the requirements of the relevant nomenclatural code, and rejected or suppressed names. A particular genus name may have zero to many synonyms, the latter case generally if the genus has been known for
10767-400: The tire inner liner producing a tire explosion". Pneumatic tires are manufactured in about 450 tire factories around the world. Tire production starts with bulk raw materials such as rubber, carbon black, and chemicals and produces numerous specialized components that are assembled and cured. Many kinds of rubber are used, the most common being styrene-butadiene copolymer . Forecasts for
10878-404: The top. The "flowers" (actually pseudanthium inflorescences ) are diverse in colour, ranging from intense blues, reds and yellows to any mixture of these and lighter shades towards white. Often, the disk flowers are much darker or lighter than the ray flowers , which also differ in morphology and are sterile . Each pseudanthium sits atop a cup- or basket-like cluster of scaly bracts , hence
10989-461: The torque applied by the drive axle to the tread to create traction but supports little of the weight of the vehicle, as is clear from the total collapse of the tire when punctured. Sidewalls are molded with manufacturer-specific detail, government-mandated warning labels, and other consumer information. Sidewall may also have sometimes decorative ornamentation that includes whitewall or red-line inserts as well as tire lettering . The shoulder
11100-507: The tread from bead to bead—so that the cords are laid at approximately right angles to the centerline of the tread, and parallel to one another—as well as stabilizer belts directly beneath the tread. The plies are generally made of nylon, polyester, or steel, and the belts of steel, fiberglass, or Kevlar . The tire’s footprint, wider than a bias tire’s, and flexible sidewalls provide a better grip in turns, and its circumferential belts stabilize it. The advantages of this construction over that of
11211-576: The values quoted are the mean of "accepted" names alone (all "uncertain" names treated as unaccepted) and "accepted + uncertain" names (all "uncertain" names treated as accepted), with the associated range of uncertainty indicating these two extremes. Within Animalia, the largest phylum is Arthropoda , with 151,697 ± 33,160 accepted genus names, of which 114,387 ± 27,654 are insects (class Insecta). Within Plantae, Tracheophyta (vascular plants) make up
11322-590: The vehicle inoperable to blowouts , where tires explode during operation and possibly damage vehicles and injure people. The manufacture of tires is often highly regulated for this reason. Because of the widespread use of tires for motor vehicles, tire waste is a substantial portion of global waste. There is a need for tire recycling through mechanical recycling and reuse, such as for crumb rubber and other tire-derived aggregate , and pyrolysis for chemical reuse, such as for tire-derived fuel . If not recycled properly or burned , waste tires release toxic chemicals into
11433-429: The virus species " Salmonid herpesvirus 1 ", " Salmonid herpesvirus 2 " and " Salmonid herpesvirus 3 " are all within the genus Salmonivirus ; however, the genus to which the species with the formal names " Everglades virus " and " Ross River virus " are assigned is Alphavirus . As with scientific names at other ranks, in all groups other than viruses, names of genera may be cited with their authorities, typically in
11544-468: The viscoelastic properties of the rubber compound (low tangent (δ) ), it comes at the cost of wet traction and grip, which requires hysteresis and energy dissipation (high tangent (δ)). A low tangent (δ) value at 60 °C is used as an indicator of low rolling resistance, while a high tangent (δ) value at 0 °C is used as an indicator of high wet traction. Designing an elastomer material that can achieve both high wet traction and low rolling resistance
11655-567: The wheel together under load and to prevent wear and tear. Early rubber tires were solid (not pneumatic). Pneumatic tires are used on many vehicles, including cars , bicycles , motorcycles , buses , trucks , heavy equipment , and aircraft . Metal tires are used on locomotives and railcars , and solid rubber (or other polymers) tires are also used in various non-automotive applications, such as casters , carts , lawnmowers , and wheelbarrows . Unmaintained tires can lead to severe hazards for vehicles and people, ranging from flat tires making
11766-408: The wheel travels. Most tires, such as those for automobiles and bicycles, are pneumatically inflated structures, providing a flexible cushion that absorbs shock as the tire rolls over rough features on the surface. Tires provide a footprint, called a contact patch , designed to match the vehicle's weight and the bearing on the surface that it rolls over by exerting a pressure that will avoid deforming
11877-477: The young whorls of Centaurea calcitrapa , both in the DPPH and in the lipid peroxidation inhibition assays, [is] very interesting and [the] species should be investigated phytochemically and biochemically focusing on these properties". Extracts from C. calcitrapa were furthermore found to have significant xanthine oxidase (XO)-inhibiting activity. Spotted knapweed as well as other species are rich in cnicin ,
11988-697: Was declared invalid because of the prior art by forgotten fellow Scot Robert William Thomson of London (patents London 1845, France 1846, USA 1847). However, Dunlop is credited with "realizing rubber could withstand the wear and tear of being a tire while retaining its resilience". John Boyd Dunlop and Harvey du Cros worked through the ensuing considerable difficulties. They employed inventor Charles Kingston Welch and acquired other rights and patents, which allowed them some limited protection of their Pneumatic Tyre business's position. Pneumatic Tyre would become Dunlop Rubber and Dunlop Tyres . The development of this technology hinged on myriad engineering advances, including
12099-528: Was estimated that for 2019 onwards, at least 3 billion tires would be sold globally every year. However, other estimates put worldwide tire production of 2,268 million in 2021 and is predicted to reach 2,665 million tires by 2027. As of 2011, the top three tire manufacturing companies by revenue were Bridgestone (manufacturing 190 million tires), Michelin (184 million), Goodyear (181 million); they were followed by Continental , and Pirelli . The Lego group produced over 318 million toy tires in 2011 and
12210-410: Was made in 1888 on May Street, Belfast , by Scots-born John Boyd Dunlop , owner of one of Ireland's most prosperous veterinary practices. It was an effort to prevent the headaches of his 10-year-old son Johnnie while riding his tricycle on rough pavements. His doctor, John, later Sir John Fagan, had prescribed cycling as an exercise for the boy and was a regular visitor. Fagan participated in designing
12321-549: Was recognized by Guinness World Records as having the highest annual production of tires by any manufacturer. A tire comprises several components: the tread, bead, sidewall, shoulder, and ply. The tread is the part of the tire that comes in contact with the road surface. The portion that is in contact with the road at a given instant in time is the contact patch . The tread is a thick rubber, or rubber/composite compound formulated to provide an appropriate level of traction that does not wear away too quickly. The tread pattern
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