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Valdivian temperate forests

The Valdivian temperate forests (NT0404) is an ecoregion on the west coast of southern South America, in Chile and Argentina. It is part of the Neotropical realm. The forests are named after the city of Valdivia. The Valdivian temperate rainforests are characterized by their dense understories of bamboos, ferns, and for being mostly dominated by evergreen angiosperm trees with some deciduous specimens, though conifer trees are also common.

Setting
Temperate rain forests comprise a relatively narrow Chilean coastal strip, between the Pacific Ocean to the west and the southern Andes Mountains to the east, from roughly 37° to 48° south latitude. North of 42°, the Chilean Coast Range stretches on, with just the north–south running Chilean Central Valley between it and the Andes. South of 42°, the coast range continues as a chain of offshore islands (including Chiloé Island and the Chonos Archipelago), while the "Central Valley" is submerged and continues as the Gulf of Corcovado. Much of the ecoregion was once covered by the Patagonian Ice Sheet and other glaciers during the peak of the last ice age, with ice descending from the Andes mountains; numerous bodies of water within the Chilean Lake District (in the central part of the ecoregion) are the remnants of ancient glacial valleys. The southern part of the region features many glacier-carved fjords.

To the north, the Valdivian forests give way to the Mediterranean forests, woodlands, and scrub of the Chilean Matorral ecoregion. A few coastal enclaves of Valdivian forest grow in north-central Chile (such as Bosque de Fray Jorge National Park) as remains of the last glacial maximum. To the south lies the Magellanic subpolar forests ecoregion. The temperate Valdivian, matorral, and Magellanic ecoregions are isolated from the subtropical/tropical forests that dominate northern South America by such landscapes as the Atacama desert (north of the matorral), the Andes Mountains, and the dry, rain-shadow Patagonian steppe east of the Andes. As a result, the temperate forest regions have evolved in relative isolation, with a high degree of endemic species.

Due to a similar location geographically and geologically (along the Pacific Plate), the coast-hugging temperate rainforests of the Pacific Northwest (from Northern California to Southern Alaska, roughly 40°-60° north latitude) exist in similar settings, with the Rocky Mountains to the east and the Pacific Ocean to the west. East of the Rocky Mountains, the North American prairie grassland stretches from south-central Canada to Texas, not unlike the Argentine grasslands to the east of the Andes. Similar to the Atacama region of Chile, the Baja California and Sonoran deserts in the US/Mexican states of California and Baja California act as climatic borders for the northwest’s rainforests.

Climate
Since the forest is located at around 40 degrees south, it is strongly influenced by the westerlies. The water vapour held by the westerlies condenses as they encounter the windward slope of the Chilean Coast Range and the Andes, creating orographic rainfall. Average annual precipitation varies from 1,000 mm at the northern edge of the ecoregion to more than 6,000 mm per year in the south. The northern portion of the ecoregion has a Submediterranean climate, with rainfall concentrated in the winter months. This seasonality decreases towards the south.

Average annual temperatures are fairly uniform within the area, especially at coastal locations where annual temperature differences between localities never exceed 7 °C. The northward-flowing oceanic Humboldt Current creates humid and foggy conditions near the coast. In the summer the temperature can climb to 16.5 °C (62 °F), while during winter the temperature can drop below 7 °C (45 °F). Winter temperatures are lower at higher elevations. The tree line is at about 2,400 m in the northern part of the ecoregion (35° S), and descends to 1,000 m in the south of the Valdivian region.

Flora
The Valdivian temperate rain forests are temperate broadleaf and mixed forests. The Valdivian and Magellanic temperate rainforests are the only temperate rain forests in South America and one of a small number of temperate rain forests in the world. Together they are the second largest in the world, after the Pacific temperate rain forests of North America (which stretches from Alaska to northern California). The Valdivian forests are a refuge for the Antarctic flora, and share many plant families with the temperate rainforests of New Zealand, Tasmania, and Australia. Fully half the species of woody plants are endemic to this ecoregion.

Chusquea quila is a bamboo that grows in humid areas below 500 m, where Chusquea culeou becomes more dominant above. Chusquea quila can form pure stands called quilantales. Very few plants can grow under this species. Other notable species are the nalca or Chilean rhubarb (Gunnera tinctoria) and the ferns Lophosoria quadripinnata and Parablechnum cordatum. Chile's national flower, the copihue (Lapageria rosea) is a pioneer species that grows in disturbed areas of the Valdivian rain forest.

The maximum plant species richness is found at latitudes 40 to 43° S.

Forest ecosystems
There are four main types of forest ecosystems in the Valdivian ecoregion.

Deciduous forests. At the northern end of the ecoregion are deciduous forests, dominated by deciduous species of southern beech, including rauli (Nothofagus alpina) and roble (N. obliqua). This is a transitional zone to the Mediterranean-climate region to the north. It grows from 35 to 36º S latitude along Chilean Coast Range, where it is known as Maulino forest. Nothofagus glauca and N. Alessandrii are predominant trees in Maulino forest. Deciduous Nothofagus forests also grow along the Andes of central Chile as far north as 33º S latitude, from approximately 1,200 meters elevation up to the tree line at 2,400 meters elevation. A krummholz of Nothofagus antarctica and N. pumilio grows near the tree line. The southern limit of these forests is 38º S latitude. Tall coniferous pehuén monkey-puzzle trees (Araucaria araucana) grow at the southern edge of the deciduous forests, from the coast at Nahuelbuta National Park to the Andes.

Valdivian laurel-leaved forests. Valdivian laurel-leaved forests, characterized by a variety of broadleaf evergreen trees, including Laureliopsis philippiana, Aextoxicon punctatum, Eucryphia cordifolia, Caldcluvia paniculata, and Weinmannia trichosperma, with an understory of Myrceugenia planipes, the arrayán (Luma apiculata) and other plants. Old-growth Valdivian evergreen forest (siempreverde) tend to form stratified canopy made up of two or three layers.

Patagonian Andean forests. The third forest type is the Patagonian Andean forests, which are distributed at higher elevations along the Andes mountain front, and are dominated by evergreen conifers, including pehuén (Araucaria araucana) and alerce (Fitzroya cupressoides). The alerce looks like a giant sequoia, and is a rival in longevity to the bristlecone pine, some with growth rings recording 3,625 years of local weather cycles. Closer to the treeline, the conifers give way to Andean scrublands of deciduous Nothofagus antarctica.

Northern Patagonian forests. The fourth and last type is the Northern Patagonian forests, which dominate the southern half of the ecoregion, with evergreen species such as the broadleaf Nothofagus dombeyi, Nothofagus betuloides and Drimys winteri and the coniferous podocarps, including Podocarpus nubigenus.

Distribution of plants follow Rapoport's rule with plant species distribution increasing at higher latitudes and decreasing at those closer to the equator, incidents of endemism becoming more frequent as one moves equatorward.

Lowland soils near the coast contain more available nutrients than more inland soils.

Origin and evolution
The flora of the forests has inherited and developed its characteristics due to a variety of causes. Its Neotropical affinities reflect its current geographic connection to the remaining South America. Its "Gondwanan" species are a legacy of the ancient supercontinent of Gondwana, a landmass formerly composed of South America, Africa, India, Antarctica and Australia. The high degree of endemic species and monospecific genera is thought to be linked to the geographic isolation came into being as result of the uplift of the Andes. There are a few "boreal" components in the Valdivian temperate rain forest which arrived by long-distance transport. Yet another component are the species from nearby South American ecosystems that adapted to the temperate rainforest.

During the Llanquihue glaciation much of the area west of Llanquihue Lake remained ice-free during the Last Glacial Maximum and had sparsely distributed vegetation dominated by Nothofagus species. Valdivian temperate rain forest proper was reduced to scattered remnants in to the west of the Andes. More specifically the refugia of the Valdivian temperate rain forest between latitudes 41 and 37° S were; the coastal region, the lower slopes of the Chilean Coast Range and the westernmost Chilean Central Valley all of which remained free of disturbance by the glacial, glacifluvial and periglacial disturbance through the glaciation.

Fauna
Some of the threatened mammals of the Valdivian forests include the monito del monte (Dromiciops gliroides), an arboreal marsupial, the southern pudú (Pudu puda) the world's smallest deer, and the kodkod (Leopardus guigna), South America's smallest cat. Since the beginning of the 20th century, there have also been nonnative wild boars living in the Valdivian forests. The Chilean climbing mouse (Irenomys tarsalis) and Chilean shrew opossum (Rhyncholestes raphanurus) are endemic to the ecoregion.

Most mammal genera in Valdivian forests are also found in semi-arid parts of Patagonia. Relative to similar forest in North America there is a low diversity of mammals in Chilean temperate forests.

The slender-billed parakeet (Enicognathus leptorhynchus) is endemic. Near-endemic and limited-range birds include the Chilean pigeon (Patagioenas araucana), Black-throated huet-huet (Pteroptochos tarnii), Chucao tapaculo (Scelorchilus rubecula), and Ochre-flanked tapaculo (Eugralla paradoxa). Hummingbirds are common in the Valdivian forests because of the presence of plants like the maqui (Aristotelia chilensis) and the copihue.

Conservation

The Valdivian forests include stands of huge trees, especially Nothofagus and Fitzroya, which can live to a great age. These magnificent rainforests are endangered by extensive logging and their replacement by fast-growing pines and eucalyptus, which are more sought-after by the pulp and paper industry. The native trees that are cleared to make way for these monocultures are often exported as woodchips to Japan. A start at conservation was made in November 2003 when a consortium of conservation groups, both local and international, bought at auction of a bankrupt logging firm 147,500 acres (600 km2) of biologically rich rainforest in the Valdivian Coastal Range. Gianni Lopez, Executive Director of CONAMA, Chile's national environmental agency remarked, "Ten years ago the existence of protected areas not owned by the government was unthinkable." Among the efforts supporting conservation, has been a growing ecotourism industry.

Protected areas
24.16% of the Valdivian temperate forests ecoregion is in protected areas.

Argentina

 * Los Alerces National Park
 * Los Arrayanes National Park
 * Lago Puelo National Park
 * Lanín National Park
 * Nahuel Huapí National Park

Chile

 * Public:

 * Alerce Andino National Park
 * Alerce Costero National Park
 * Altos de Lircay National Reserve
 * Altos de Pemehue National Reserve
 * Bosque de Fray Jorge National Park
 * Carlos Anwandter Sanctuary
 * Chiloé National Park
 * China Muerta National Reserve
 * Conguillío National Park
 * Corcovado National Park
 * Coyhaique National Reserve
 * Futaleufú National Reserve
 * Hornopirén National Park
 * Huerquehue National Park
 * Isla Guamblin National Park
 * La Campana National Park
 * Lago Rosselot National Reserve
 * Laguna del Laja National Park
 * Laguna San Rafael National Park
 * Lahuen Ñadi Natural Monument
 * Llanquihue National Reserve
 * Los Bellotos del Melado National Reserve
 * Los Huemules de Niblinto National Reserve
 * Los Queules National Reserve
 * Los Ruiles National Reserve
 * Melimoyu National Park
 * Mocho-Choshuenco National Reserve
 * Nahuelbuta National Park
 * Nonguén National Park
 * Península de Hualpén Nature Sanctuary
 * Pumalín Douglas Tompkins National Park
 * Puyehue National Park
 * Queulat National Park
 * Radal Siete Tazas National Park
 * Ralco National Reserve
 * Río Los Cipreses National Reserve
 * Tolhuaca National Park
 * Vicente Perez Rosales National Park
 * Villarrica National Park
 * Private:

 * Huilo-Huilo Biological Reserve (owned by Víctor Peterman)
 * Llancahue (administered by the Austral University of Chile)
 * Los Vertientes Private Nature Reserve
 * Meullín-Puye Nature Sanctuary (administered by the Kreen Foundation)
 * Oncol Park (owned by Celulosa Arauco y Constitución)
 * Área Costera Protegida Punta Curiñanco (owned by CODEFF)
 * Tantauco Park (owned by Sebastián Piñera)
 * Valdivian Coastal Reserve (owned by The Nature Conservancy)

title: Valdivian temperate forests


text:
Rivet

A rivet is a permanent mechanical fastener. Before being installed, a rivet consists of a smooth cylindrical shaft with a head on one end. The end opposite the head is called the tail. On installation, the deformed end is called the shop head or buck-tail.

Because there is effectively a head on each end of an installed rivet, it can support tension loads. However, it is much more capable of supporting shear loads (loads perpendicular to the axis of the shaft).

Fastenings used in traditional wooden boat building, such as copper nails and clinch bolts, work on the same principle as the rivet but were in use long before the term rivet was introduced and, where they are remembered, are usually classified among nails and bolts respectively.

History
Rivet holes have been found in Egyptian spearheads dating back to the Naqada culture of between 4400 and 3000 B.C. Archeologists have also uncovered many Bronze Age swords and daggers with rivet holes where the handles would have been. The rivets themselves were essentially short rods of metal, which metalworkers hammered into a pre-drilled hole on one side and deformed on the other to hold them in place.

Types
There are several types of rivets, designed to meet different cost, accessibility, and strength requirements:

Solid/round head rivets

Solid rivets are one of the oldest and most reliable types of fasteners, having been found in archaeological findings dating back to the Bronze Age. Solid rivets consist simply of a shaft and head that are deformed with a hammer or rivet gun. A rivet compression or crimping tool can also deform this type of rivet. This tool is mainly used on rivets close to the edge of the fastened material since the tool is limited by the depth of its frame. A rivet compression tool does not require two people and is generally the most foolproof way to install solid rivets.

Solid rivets are used in applications where reliability and safety count. A typical application for solid rivets can be found within the structural parts of aircraft. Hundreds of thousands of solid rivets are used to assemble the frame of a modern aircraft. Such rivets come with rounded (universal) or 100° countersunk heads. Typical materials for aircraft rivets are aluminium alloys (2017, 2024, 2117, 7050, 5056, 55000, V-65), titanium, and nickel-based alloys (e.g., Monel). Some aluminium alloy rivets are too hard to buck and must be softened by solution treating (precipitation hardening) prior to being bucked. "Ice box" aluminium alloy rivets harden with age, and must likewise be annealed and then kept at sub-freezing temperatures (hence the name "ice box") to slow the age-hardening process. Steel rivets can be found in static structures such as bridges, cranes, and building frames.

The setting of these fasteners requires access to both sides of a structure. Solid rivets are driven using a hydraulically, pneumatically, or electromagnetically actuated squeezing tool or even a handheld hammer. Applications where only one side is accessible require "blind" rivets.

Solid rivets are also used by some artisans in the construction of modern reproduction of medieval armour, jewellery and metal couture.

High-strength structural steel rivets
Until relatively recently, structural steel connections were either welded or riveted. High-strength bolts have largely replaced structural steel rivets. Indeed, the latest steel construction specifications published by AISC (the 14th Edition) no longer cover their installation. The reason for the change is primarily due to the expense of skilled workers required to install high-strength structural steel rivets. Whereas two relatively unskilled workers can install and tighten high-strength bolts, it normally takes four skilled workers to install rivets (warmer, catcher, holder, basher).

At a central location near the areas being riveted, a furnace was set up. Rivets were placed in the furnace and heated to approximately 900 °C or "cherry red". The rivet warmer or cook used tongs to remove individual rivets and throw them to a catcher stationed near the joints to be riveted. The catcher (usually) caught the rivet in a leather or wooden bucket with an ash-lined bottom. The catcher inserted the rivet into the hole to be riveted, then quickly turned to catch the next rivet. The holder up or holder on would hold a heavy bucking bar or dolly or another (larger) pneumatic jack against the round "shop head" of the rivet, while the riveter (sometimes two riveters) applied a hammer or pneumatic rivet hammer With a "rivet set" to the tail of the rivet, making it mushroom against the joint forming the "field head" into its final domed shape. Alternatively, the buck is hammered more or less flush with the structure in a counter-sunk hole. On cooling, the rivet contracted axially exerting the clamping force on the joint. Before the use of pneumatic hammers, e.g. in the construction of RMS Titanic, the person who hammered the rivet was known as the "basher".

The last commonly used high-strength structural steel rivets were designated ASTM A502 Grade 1 rivets.

Such riveted structures may be insufficient to resist seismic loading from earthquakes if the structure was not engineered for such forces, a common problem of older steel bridges. This is because a hot rivet cannot be properly heat treated to add strength and hardness. In the seismic retrofit of such structures, it is common practice to remove critical rivets with an oxygen torch, precision ream the hole, then insert a machined and heat-treated bolt.

Semi-tubular rivets
Semi-tubular rivets (also known as tubular rivets) are similar to solid rivets, except they have a partial hole (opposite the head) at the tip. The purpose of this hole is to reduce the amount of force needed for application by rolling the tubular portion outward. The force needed to apply a semi-tubular rivet is about 1/4 of the amount needed to apply a solid rivet. Tubular rivets are sometimes preferred for pivot points (a joint where movement is desired) since the swelling of the rivet is only at the tail. The type of equipment used to apply semi-tubular rivets ranges from prototyping tools to fully automated systems. Typical installation tools (from lowest to highest price) are hand set, manual squeezer, pneumatic squeezer, kick press, impact riveter, and finally PLC-controlled robotics. The most common machine is the impact riveter and the most common use of semi-tubular rivets is in lighting, brakes, ladders, binders, HVAC duct-work, mechanical products, and electronics. They are offered from 1/16-inch (1.6 mm) to 3/8-inch (9.5 mm) in diameter (other sizes are considered highly special) and can be up to 8 inches (203 mm) long. A wide variety of materials and platings are available, most common base metals are steel, brass, copper, stainless, aluminum and the most common platings are zinc, nickel, brass, tin. Tubular rivets are normally waxed to facilitate proper assembly. An installed tubular rivet has a head on one side, with a rolled-over and exposed shallow blind hole on the other.

Blind rivets

Blind rivets, commonly referred to as "pop" rivets (POP is the brand name of the original manufacturer, now owned by Stanley Engineered Fastening, a division of Stanley Black & Decker) are tubular and are supplied with a nail-like mandrel through the center which has a "necked" or weakened area near the head. The rivet assembly is inserted into a hole drilled through the parts to be joined and a specially designed tool is used to draw the mandrel through the rivet. The compression force between the head of the mandrel and the tool expands the diameter of the tube throughout its length, locking the sheets being fastened if the hole was the correct size. The head of the mandrel also expands the blind end of the rivet to a diameter greater than that of the drilled hole, compressing the fastened sheets between the head of the rivet and the head of the mandrel. At a predetermined tension, the mandrel breaks at the necked location. With open tubular rivets, the head of the mandrel may or may not remain embedded in the expanded portion of the rivet, and can come loose at a later time. More expensive closed-end tubular rivets are formed around the mandrel so the head of the mandrel is always retained inside the blind end after installation. "Pop" rivets can be fully installed with access to only one side of a part or structure.

Prior to the invention of blind rivets, installation of a rivet typically required access to both sides of the assembly: a rivet hammer on one side and a bucking bar on the other side. In 1916, Royal Navy reservist and engineer Hamilton Neil Wylie filed a patent for an "improved means of closing tubular rivets" (granted May 1917). In 1922 Wylie joined the British aircraft manufacturer Armstrong-Whitworth Ltd to advise on metal construction techniques; here he continued to develop his rivet design with a further 1927 patent that incorporated the pull-through mandrel and allowed the rivet to be used blind. By 1928, the George Tucker Eyelet Company, of Birmingham, England, produced a "cup" rivet based on the design. It required a separate GKN mandrel and the rivet body to be hand-assembled prior to use for the building of the Siskin III aircraft. Together with Armstrong-Whitworth, the Geo. Tucker Co. further modified the rivet design to produce a one-piece unit incorporating a mandrel and rivet. This product was later developed in aluminium and trademarked as the "POP" rivet. The United Shoe Machinery Co. produced the design in the U.S. as inventors such as Carl Cherry and Lou Huck experimented with other techniques for expanding solid rivets.

They are available in flat head, countersunk head, and modified flush head with standard diameters of 1/8, 5/32, and 3/16 inch. Blind rivets are made from soft aluminum alloy, steel (including stainless steel), copper, and Monel.

There are also , which are designed to take shear and tensile loads.

The rivet body is normally manufactured using one of three methods:

There is a vast array of specialty blind rivets that are suited for high strength or plastic applications. Typical types include:

Internally and externally locked structural blind rivets can be used in aircraft applications because, unlike other types of blind rivets, the locked mandrels cannot fall out and are watertight. Since the mandrel is locked into place, they have the same or greater shear-load-carrying capacity as solid rivets and may be used to replace solid rivets on all but the most critical stressed aircraft structures.

The typical assembly process requires the operator to install the rivet in the nose of the tool by hand and then actuate the tool. However, in recent years automated riveting systems have become popular in an effort to reduce assembly costs and repetitive disorders. The cost of such tools ranges from US$1,500 for auto-feed pneumatics to US$50,000 for fully robotic systems.

While structural blind rivets using a locked mandrel are common, there are also aircraft applications using "non-structural" blind rivets where the reduced, but still predictable, strength of the rivet without the mandrel is used as the design strength. A method popularized by Chris Heintz of Zenith Aircraft uses a common flat-head (countersunk) rivet which is drawn into a specially machined nosepiece that forms it into a round-head rivet, taking up much of the variation inherent in hole size found in amateur aircraft construction. Aircraft designed with these rivets use rivet strength figures measured with the mandrel removed.

Oscar rivets
Oscar rivets are similar to blind rivets in appearance and installation but have splits (typically three) along the hollow shaft. These splits cause the shaft to fold and flare out (similar to the wings on a toggle bolt's nut) as the mandrel is drawn into the rivet. This flare (or flange) provides a wide bearing surface that reduces the chance of rivet pull-out. This design is ideal for high-vibration applications where the back surface is inaccessible.

A version of the Oscar rivet is the Olympic rivet which uses an aluminum mandrel that is drawn into the rivet head. After installation, the head and mandrel are shaved off flush resulting in an appearance closely resembling a brazier head-driven rivet. They are used in the repair of Airstream trailers to replicate the look of the original rivets.

Drive rivet
A drive rivet is a form of blind rivet that has a short mandrel protruding from the head that is driven in with a hammer to flare out the end inserted in the hole. This is commonly used to rivet wood panels into place since the hole does not need to be drilled all the way through the panel, producing an aesthetically pleasing appearance. They can also be used with plastic, metal, and other materials and require no special setting tool other than a hammer and possibly a backing block (steel or some other dense material) placed behind the location of the rivet while hammering it into place. Drive rivets have less clamping force than most other rivets. Drive screws, possibly another name for drive rivets, are commonly used to hold nameplates into blind holes. They typically have spiral threads that grip the side of the hole.

Flush rivet
A flush rivet is used primarily on external metal surfaces where good appearance and the elimination of unnecessary aerodynamic drag are important. A flush rivet takes advantage of a countersunk or dimpled hole; they are also commonly referred to as countersunk rivets. Countersunk or flush rivets are used extensively on the exterior of aircraft for aerodynamic reasons such as reduced drag and turbulence. Additional post-installation machining may be performed to perfect the airflow.

Flush riveting was invented in America in the 1930s by Vladimir Pavlecka and his team at Douglas Aircraft. The technology was used by Howard Hughes in the design and production of his H-1 plane, the Hughes H-1 Racer.

Friction-lock rivet
These resemble an expanding bolt except the shaft snaps below the surface when the tension is sufficient. The blind end may be either countersunk ('flush') or dome-shaped.

One early form of blind rivet that was the first to be widely used for aircraft construction and repair was the Cherry friction-lock rivet. Originally, Cherry friction locks were available in two styles, hollow shank pull-through and self-plugging types. The pull-through type is no longer common; however, the self-plugging Cherry friction-lock rivet is still used for repairing light aircraft.

Cherry friction-lock rivets are available in two head styles, universal and 100-degree countersunk. Furthermore, they are usually supplied in three standard diameters, 1/8, 5/32 and 3/16 inch.

A friction-lock rivet cannot replace a solid shank rivet, size for size. When a friction lock is used to replace a solid shank rivet, it must be at least one size larger in diameter because the friction-lock rivet loses considerable strength if its center stem falls out due to vibrations or damage.

Self-piercing rivets
Self-pierce riveting (SPR) is a process of joining two or more materials using an engineered rivet. Unlike solid, blind and semi-tubular rivets, self-pierce rivets do not require a drilled or punched hole.

SPRs are cold-forged to a semi-tubular shape and contain a partial hole to the opposite end of the head. The end geometry of the rivet has a chamfered poke that helps the rivet pierce the materials being joined. A hydraulic or electric servo rivet setter drives the rivet into the material, and an upsetting die provides a cavity for the displaced bottom sheet material to flow. The SPR process is described in here SPR process.

The self-pierce rivet fully pierces the top sheet material(s) but only partially pierces the bottom sheet. As the tail end of the rivet does not break through the bottom sheet it provides a water or gas-tight joint. With the influence of the upsetting die, the tail end of the rivet flares and interlocks into the bottom sheet forming a low profile button.

Rivets need to be harder than the materials being joined. they are heat treated to various levels of hardness depending on the material's ductility and hardness. Rivets come in a range of diameters and lengths depending on the materials being joined; head styles are either flush countersunk or pan heads.

Depending on the rivet setter configuration, i.e. hydraulic, servo, stroke, nose-to-die gap, feed system etc., cycle times can be as quick as one second. Rivets are typically fed to the rivet setter nose from tape and come in cassette or spool form for continuous production.

Riveting systems can be manual or automated depending on the application requirements; all systems are very flexible in terms of product design and ease of integration into a manufacturing process.

SPR joins a range of dissimilar materials such as steel, aluminum, plastics, composites and pre-coated or pre-painted materials. Benefits include low energy demands, no heat, fumes, sparks or waste and very repeatable quality.

Compression rivets
Compression rivets are commonly used for functional or decorative purposes on clothing, accessories, and other items. They have male and female halves that press together, through a hole in the material. Double cap rivets have aesthetic caps on both sides. Single cap rivets have caps on just one side; the other side is low profile with a visible hole. Cutlery rivets are commonly used to attach handles to knife blades and other utensils.

Sizes
Rivets come in both inch series and metric series: The main official standards relate more to technical parameters such as ultimate tensile strength and surface finishing than physical length and diameter. They are:
 * Imperial units (fractions of inches) with diameters such as 1/8″  or 5/16″.
 * Système international or SI units with diameters such as 3 mm, 8 mm.

Imperial
Rivet diameters are commonly measured in $1/undefined$-inch increments and their lengths in $1/undefined$-inch increments, expressed as "dash numbers" at the end of the rivet identification number. A "dash 3 dash 4" (XXXXXX-3-4) designation indicates a $3/32$-inch diameter and $4/16$-inch (or $1/4$-inch) length. Some rivets lengths are also available in half sizes, and have a dash number such as –3.5 ($7/32$ inch) to indicate they are half-size. The letters and digits in a rivet's identification number that precede its dash numbers indicate the specification under which the rivet was manufactured and the head style. On many rivets, a size in 32nds may be stamped on the rivet head. Other makings on the rivet head, such as small raised or depressed dimples or small raised bars indicate the rivet's alloy.

To become a proper fastener, a rivet should be placed in a hole ideally 4–6 thousandths of an inch larger in diameter. This allows the rivet to be easily and fully inserted, then setting allows the rivet to expand, tightly filling the gap and maximizing strength.

Metric
Rivet diameters and lengths are measured in millimeters. Conveniently, the rivet diameter relates to the drill required to make a hole to accept the rivet, rather than the actual diameter of the rivet, which is slightly smaller. This facilitates the use of a simple drill-gauge to check both rivet and drill are compatible. For general use, diameters between 2 mm – 20 mm and lengths from 5 mm – 50 mm are common. The design type, material and any finish is usually expressed in plain language (often English).

Applications

Before welding techniques and bolted joints were developed, metal-framed buildings and structures such as the Eiffel Tower, Shukhov Tower and the Sydney Harbour Bridge were generally held together by riveting, as were automobile chassis. Riveting is still widely used in applications where light weight and high strength are critical, such as in an aircraft. Sheet metal alloys used in aircraft skins are generally not welded, because the aircraft in high-speed flight skins will be stretched, extrusion may occur deformation and change in material properties. Riveting can reduce the vibration transmission between joints, thereby reducing the risk of cracking. The firmness is better and more reliable against such repeated stress changes. In order to reduce air resistance, countersunk rivets are generally used in aircraft skins.

A large number of countries used rivets in the construction of armored tanks during World War II, including the M3 Lee (General Grant) manufactured in the United States. However, many countries soon learned that rivets were a large weakness in tank design since if a tank was hit by a large projectile it would dislocate the rivets and they would fly around the inside of the tank and injure or kill the crew, even if the projectile did not penetrate the armor. Some countries such as Italy, Japan, and Britain used rivets in some or all of their tank designs throughout the war for various reasons, such as lack of welding equipment or inability to weld very thick plates of armor effectively.

Blind rivets are used almost universally in the construction of plywood road cases.

Common but more exotic uses of rivets are to reinforce jeans and to produce the distinctive sound of a sizzle cymbal.

Joint analysis
The stress and shear in a rivet are analyzed like a bolted joint. However, it is not wise to combine rivets with bolts and screws in the same joint. Rivets fill the hole where they are installed to establish a very tight fit (often called an interference fit). It is difficult or impossible to obtain such a tight fit with other fasteners. The result is that rivets in the same joint with loose fasteners carry more of the load—they are effectively stiffer. The rivet can then fail before it can redistribute load to the other loose-fit fasteners like bolts and screws. This often causes catastrophic failure of the joint when the fasteners unzip. In general, a joint composed of similar fasteners is the most efficient because all fasteners reach capacity simultaneously.

Solid and semi-tubular rivets
There are several methods for installing solid rivets. Rivets small enough and soft enough are often bucked. In this process, the installer places a rivet gun against the factory head and holds a bucking bar against the tail or a hard working surface. The bucking bar is a specially shaped solid block of metal. The rivet gun provides a series of high-impulse forces that upsets and work hardens the tail of the rivet between the work and the inertia of the bucking bar. Rivets that are large or hard may be more easily installed by squeezing instead. In this process, a tool in contact with each end of the rivet clinches to deform the rivet.
 * Manual with hammer and handset or bucking bar
 * Pneumatic hammers
 * Handheld squeezers
 * Riveting machines
 * Pin hammer, rivet set

Rivets may also be upset by hand, using a ball-peen hammer. The head is placed in a special hole made to accommodate it, known as a rivet-set. The hammer is applied to the buck-tail of the rivet, rolling an edge so that it is flush against the material.

Solid rivets for construction
A hammer is also used to "ring" an installed rivet, as a non-destructive test for tightness and imperfections. The inspector taps the head (usually the factory head) of the rivet with the hammer while touching the rivet and base plate lightly with the other hand and judges the quality of the audibly returned sound and the feel of the sound traveling through the metal to the operator's fingers. A rivet tightly set in its hole returns a clean and clear ring, while a loose rivet produces a recognizably different sound.

Testing of blind rivets
A blind rivet has strength properties that can be measured in terms of shear and tensile strength. Occasionally rivets also undergo performance testing for other critical features, such as pushout force, break load and salt spray resistance. A standardized destructive test according to the Inch Fastener Standards is widely accepted.

The shear test involves installing a rivet into two plates at specified hardness and thickness and measuring the force necessary to shear the plates. The tensile test is basically the same, except that it measures the pullout strength. Per the IFI-135 standard, all blind rivets produced must meet this standard. These tests determine the strength of the rivet, and not the strength of the assembly. To determine the strength of the assembly a user must consult an engineering guide or the Machinery's Handbook.

Alternatives

 * Adhesives
 * Bolted joints
 * Brazing
 * Clinching
 * Folded joints
 * Nails
 * Screws
 * Soldering
 * Welding

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Rivet


text:
Cuthred of Kent

Cuthred (Old English: Cuþræd) was the King of Kent from 798 to 807.

After the revolt of Kent under Eadberht III Præn was defeated in 798 by Coenwulf, Cuthred was established as a client king. During Cuthred's reign, the Archbishopric of Lichfield was formally abolished at the Council of Clovesho on 12 October 803, and the Archbishopric of Canterbury thus regained the status of which Offa of Mercia had sought to deprive it. Cuthred's reign also saw the first raids of Kent by the Vikings. After his death in 807, Cœnwulf seems to have acted as King of Kent.

Cuthred died in 807, according to the Anglo-Saxon Chronicle. He issued coins and charters. His surviving charters are both dated 805, one precisely to 26 July 805, in the eighth year of his reign, so his accession fell between 27 July 797 and 26 July 798. In two charters issued by Cœnwulf, King of Mercia, he is described as brother of that king.

Family

Cuthred has been identified as one of three known sons of Cuthberht of Mercia, his brothers were Coenwulf (King of Mercia 796-821) and Ceolwulf (King of Mercia 821-823)

Cuthred has been identified as the father of Coenwald, and may also be the father of Cyneberht.

title: Cuthred of Kent


text:
Moshe Greenberg

Moshe Greenberg (משה גרינברג; July 10, 1928 – May 15, 2010) was an American rabbi, Bible scholar, and professor emeritus of the Hebrew University of Jerusalem.

Biography
Moshe Greenberg was born in Philadelphia in 1928. Raised in a Hebrew-speaking Zionist home, he studied Bible and Hebrew literature from his youth. His father, Rabbi Simon Greenberg, was the rabbi of Har Zion Temple and one of the most important leaders of the Conservative movement. Moshe Greenberg received his doctorate from the University of Pennsylvania in 1954, studying  Bible and Assyriology under E. A. Speiser; simultaneously, he studied post-Biblical Judaica at the Jewish Theological Seminary of America (JTSA), where he was ordained as a rabbi. Greenberg was married to Evelyn Gelber and had three sons. He died in Jerusalem after a long illness.

Academic and literary career
Greenberg taught Bible and Judaica at the University of Pennsylvania from 1964-1970. He held a chair in Jewish studies at the Hebrew University of Jerusalem, an institution at which he had taught since 1970. He also taught at Swarthmore College, the JTSA, the University of California, Berkeley and the Schechter Institute of Jewish Studies. Greenberg was editor-in-chief of the Ketuvim section of the Jewish Publication Society of America's new English translation of the Bible. He was the author of ten books and numerous articles. From 1994-1995 he held a fellowship at the Katz Center for Advanced Judaic Studies, doing research in Historiography.

Scholarship
Greenberg was the first Jewish Bible scholar appointed to a position in a secular university after World War II and had an important influence on the development of Biblical scholarship. He focused on the phenomenology of biblical religion and law, the theory and practice of interpreting biblical texts, and the role of the Bible in Jewish thought. In the area of prayer, Greenberg studied the development of biblical petition and praise, which he portrayed as  "a vehicle of humility, an expression of  un-selfsufficiency, which in biblical thought, is the proper stance  of  humans before God" (Studies, 75-108). He showed that the prose prayers embedded in biblical narratives reflect the piety of commoners, and reasoned that the frequency of spontaneous prayer strengthened the egalitarian tendency of Israelite religion which led to the establishment of  the  synagogue. In the area  of biblical law, Greenberg argued that "the law [is] the expression of underlying postulates or  values of culture" and that differences  between biblical and ancient Near Eastern laws  were not reflections  of  different stages of social  development  but  of different underlying legal and religious principles (Studies, 25-41). Analyzing economic, social, political,  and religious laws in the Torah, he showed that they dispersed authority throughout society and prevented the monopolization of prestige and  power by narrow elite groups (Studies, 51-61). In his commentaries on Exodus (1969) and Ezekiel (1983, 1997), Greenberg developed  a "holistic"  method  of  exegesis, redirecting attention from the text's  "hypothetically  reconstructed  elements"  to the  biblical  books  as integral  wholes and products of  thoughtful  and  artistic design. Greenberg's studies of Jewish thought include studies of the intellectual  achievements  of  medieval  Jewish   exegesis, investigations  of rabbinic  reflections on defying illegal orders (Studies, 395-403), and  attitudes toward members of other  religions  (Studies, 369-393; "A Problematic Heritage"). He argued that a Scripture-based  religion must avoid fundamentalism through selectivity and re-prioritizing values.

Awards

 * In 1961, Greenberg was awarded a Guggenheim Fellowship.
 * He was also awarded the Harrison Prize for Distinguished Teaching and Research.
 * In 1994, he was awarded the Israel Prize in Bible. Greenberg also taught at Beyt Midrash leShalom, the Peace Study Center sponsored jointly by the Israeli Religious Peace Movement Netivot Shalom and by Tikkun Magazine.

Published works

 * Hab Piru, 1955
 * Introduction to Hebrew, 1965
 * Understanding Exodus, 1967
 * Biblical Prose Prayer as a Window to the Popular Religion of Ancient Israel, 1983
 * Ezekiel in the Anchor Bible Series 3 volumes, 1983, 1997 (third volume was to be completed by Jacob Milgrom, who died June 5, 2010)
 * Torah: Five Books of Moses, 2000

title: Moshe Greenberg


text:
User talk:Dav4is

Hello, welcome to Wikipedia. Here's some tips:
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Other useful pages are: how to edit, how to write a great article, naming conventions, manual of style and the Wikipedia policies.

I hope you enjoy editing here and being a Wikipedian! Angela. 22:53, Mar 6, 2004 (UTC)

Harrison family
I think that within the, everyone should be sorted by their first name, and not by the default order. That's why I had left in that article. It overrides in that case. What do you think? Neier 23:12, 5 March 2007 (UTC)

Sorry, I disagree. The convention is to sort by surname, even when the list elements are presented as "given-name surname". See Categorization, particularly the example of Category:Presidents of the United States.

I know that, in the case of a family category, this may seem to overload one particular index (H, in this case), but to sort by given name just confuses things, with some name categories sorted by surname, others by given name. -dav4is 10:37, 6 March 2007 (UTC)

 * I put them all back under the H, including a few which were under W before I started. Neier 14:10, 6 March 2007 (UTC)

Tx. -dav4is

John Wayne / Tommy Morrison
I liked that one approach of citing answers.com (a wikipedia mirror site). In Geometry class, we used to call that "using the theorem to prove the theorem." If it's really true, it ought to be out there somewhere. Baseball Bugs What's up, Doc? 13:57, 6 September 2007 (UTC)

Misc
Good luck with your article - thanks for starting it before referencing it. Martinvl (talk) 15:40, 23 January 2010 (UTC)

Parting stone
Just a query, as you make progress with Parting stone, as to whether this might not be a type of Boundary marker (which includes Boundary stones) and might be worth including there rather than  as a separate article ?  Velela  Velela Talk 15:50, 23 January 2010 (UTC)

Hi, Velela]. I considered that, but decided against it because there is no boundary involved with a Parting stone. In each of its senses, a Parting stone marks only a point in space -- and in time in the case of a memorial parting stone. -dav4is (talk) 17:38, 25 January 2010 (UTC)

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Speedy deletion nomination of Lists of people with specific surnames
Hello Dav4is,

I wanted to let you know that I just tagged Lists of people with specific surnames for deletion, because it doesn't appear to contain any encyclopedic content. Take a look at our suggestions for essential content in short articles to learn what should be included.

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You can leave a note on my talk page if you have questions. Thanks,

Chihin.chong (talk) 20:10, 6 May 2013 (UTC)

Nomination of Lists of people with specific surnames for deletion
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Speedy deletion nomination of Noel Loomis

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Speedy deletion nomination of Noel Loomis

Hello, and welcome to Wikipedia. This is a notice to inform you that a tag has been placed on Noel Loomis requesting that it be speedily deleted from Wikipedia. This has been done under section A3 of the criteria for speedy deletion, because it is an article with no content whatsoever, or whose contents consist only of external links, a "See also" section, book references, category tags, template tags, interwiki links, images, a rephrasing of the title, or an attempt to contact the subject of the article. Please see Wikipedia:Stub for our minimum information standards for short articles. Also please note that articles must be on notable subjects and should provide references to reliable sources that verify their content.

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Wikilinking
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Thanks, and my best wishes.

Tony  (talk)  03:40, 22 April 2014 (UTC)

Category:People descended from Joseph Loomis
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title: User talk:Dav4is


text:
Ostracod

Ostracods, or ostracodes, are a class of the Crustacea (class Ostracoda), sometimes known as seed shrimp. Some 33,000 species (only 13,000 of which are extant) have been identified, grouped into 7 valid orders. They are small crustaceans, typically around 1 mm in size, but varying from 0.2 to 30 mm in the case of the marine Gigantocypris. The largest known freshwater species is Megalocypris princeps, which reach 8mm in length. In most cases, their bodies are flattened from side to side and protected by a bivalve-like valve or "shell" made of chitin, and often calcium carbonate. The family Entocytheridae and many planktonic forms do not have calcium carbonate. The hinge of the two valves is in the upper (dorsal) region of the body. Ostracods are grouped together based on shell and soft part morphology, and molecular studies have not unequivocally supported the group's monophyly. They have a wide range of diets, and the class includes carnivores, herbivores, scavengers and filter feeders, but most ostracods are deposit feeders.

Etymology
Ostracod comes from the Greek óstrakon meaning shell or tile.

Fossils
Ostracods are "by far the most common arthropods in the fossil record" with fossils being found from the early Ordovician to the present. An outline microfaunal zonal scheme based on both Foraminifera and Ostracoda was compiled by M. B. Hart. Freshwater ostracods have even been found in Baltic amber of Eocene age, having presumably been washed onto trees during floods.

Ostracods have been particularly useful for the biozonation of marine strata on a local or regional scale, and they are invaluable indicators of paleoenvironments because of their widespread occurrence, small size, easily preservable, generally moulted, calcified bivalve carapaces; the valves are a commonly found microfossil.

A find in Queensland, Australia in 2013, announced in May 2014, at the Bicentennary Site in the Riversleigh World Heritage area, revealed both male and female specimens with very well preserved soft tissue. This set the Guinness World Record for the oldest penis. Males had observable sperm that is the oldest yet seen and, when analysed, showed internal structures and has been assessed as being the largest sperm (per body size) of any animal recorded. It was assessed that the fossilisation was achieved within several days, due to phosphorus in the bat droppings of the cave where the ostracods were living.

Description
The body of an ostracod is encased by a carapace originating from the head region, and consists of two valves superficially resembling the shell of a clam. A distinction is made between the valve (hard parts) and the body with its appendages (soft parts). Studies of the embryonic development in Myodocopida shows that the bivalved carapace developes from two independent buds of the carapace valves. As the two halves grows, they meet in the middle. In Manawa, an ostracod in the order Palaeocopida, the carapace originates as a single element and during growth folds at the midline.

Body parts
The body consists of a head and thorax, separated by a slight constriction. Unlike many other crustaceans, the body is not clearly divided into segments. Most species have completely or partly lost their trunk segmentation, and there are no boundaries between the thorax and abdomen, and it has therefore been impossible to tell if the first pair of limbs after the maxillae belongs to the head or the thorax. With a few exception, like platycopids which have an 11-segmented trunk, the abdomen in ostracods has no visible segments.

The head is the largest part of the body, and bears four pairs of appendages. Two pairs of well-developed antennae are used to swim through the water. In addition, there are a pair of mandibles and a pair of maxillae. The thorax has three primary pairs of appendages. The first of these has different functions in different groups. It can be used for feeding (Cypridoidea) or for walking (Cytheroidea), and in some species it has evolved into a male clasping organ. The second pair is mainly used for locomotion, and the third is used for walking or cleaning, but can also be reduced or absent. Both the second and third pair are absent in suborder Cladocopina. In the Myodocopina the third pair is a multisegmented cleaning organ that resembles a worm. Their external genitals seem to originate from the fusion of three to five appendages. The two "rami", or projections, from the tip of the tail point downward and slightly forward from the rear of the shell.

All ostracods have a pair of "ventilatory appendages" that beat rhythmically, which create a water current between the body and the inner surface of the carapace. Podocopa, the largest subclass, have no gills, heart or circulatory system, so the gas exchange take place all over the surface. The other subclass of ostracods, the Myodocopa, do have a heart, and the family Cylindroleberididae also have 6-8 lamellar gills. Certain other larger members of Myodocopa, even if they don't have gills, have a circulatory system where hemolymph sinuses absorbs oxygen through special areas on the inner wall of the carapace. In addition, the respiratory protein hemocyanin has been found in the two orders Myodocopida and Platycopida. Nitrogenous waste is excreted through glands on the maxillae, antennae, or both.

The primary sense of ostracods is likely touch, as they have several sensitive hairs on their bodies and appendages. Compound eyes are only found in Myodocopina within the Myodocopa. The order Halocyprida in the same subclass is eyeless. Podocopid ostracods have just a naupliar eye consisting of two lateral ocelli and a single ventral ocellus, but the ventral one is absent in some species. Platycopida was assumed to be completely eyeless, but two species, Keijcyoidea infralittoralis and Cytherella sordida, have been found to both possess a nauplius eye too.

Palaeoclimatic reconstruction
A new method is in development called mutual ostracod temperature range (MOTR), similar to the mutual climatic range (MCR) used for beetles, which can be used to infer palaeotemperatures. The ratio of oxygen-18 to oxygen-16 (δ18O) and the ratio of magnesium to calcium (Mg/Ca) in the calcite of ostracod valves can be used to infer information about past hydrological regimes, global ice volume and water temperatures.

Distribution
Ecologically, marine ostracods can be part of the zooplankton or (most commonly) are part of the benthos, living on or inside the upper layer of the sea floor. Ostracods has been found as deep as 9,307 m (genus Krithe in family Krithidae). Subclass Myodocopa and the two podocop orders Palaeocopida and Platycopida are restricted to marine environments (except for Platycopida which have a few brackish species),  but we find non-marine forms in the four superfamilies Terrestricytheroidea, Cypridoidea, Darwinuloidea, and Cytheroidea in the order Podocopida. Terrestricytheroidea is semi-terrestrial and usually found in brackish and marine-influenced environments such as salt marshes, but not in freshwater. The other three superfamilies also live in freshwater (Darwinuloidea is exclusively non-marine). Of these three, only Cypridoidea have freshwater species able to swim. Representatives living in terrestrial habitats are also found in all three freshwater groups, such as genus Mesocypris which is known from humid forest soils of South Africa, Australia and New Zealand.

As of 2008, around 2000 species and 200 genera of non-marine ostracods are found. However, a large portion of diversity is still undescribed, indicated by undocumented diversity hotspots of temporary habitats in Africa and Australia. Non-marine species have been found to live in sulfidic cave ecosystems such as the Movile Cave, deep groundwaters, hypersaline waters, acidic waters with pH as low as 3.4, phytotelmata in plants like bromeliads, and in temperatures varying from almost freezing to more than 50 °C in hot springs. Of the known specific and generic diversity of non-marine ostracods, half (1000 species, 100 genera) belongs to one family (of 13 families), Cyprididae. Many Cyprididae occur in temporary water bodies and have drought-resistant eggs, mixed/parthenogenetic reproduction, and the ability to swim. These biological attributes preadapt them to form successful radiations in these habitats.

Lifecycle
Male ostracods have two penises, corresponding to two genital openings (gonopores) on the female. The individual sperm are often large, and are coiled up within the testis prior to mating; in some cases, the uncoiled sperm can be up to six times the length of the male ostracod itself. Mating typically occurs during swarming, with large numbers of females swimming to join the males. Some species are partially or wholly parthenogenetic. Superfamily Darwinuloidea was assumed to have reproduced asexually for the last 200 million years, but rare males have since been discovered in one of the species. In the subclass Myodocopa, all members of the order Myodocopida have brood care, releasing their offspring as first instars, allowing a pelagic lifestyle. In the order Halocyprida the eggs are released directly into the sea, except for a single genus with brood care. In the subclass Podocopa, brood care is only found in Darwinulocopina and some Cytherocopina in the order Podocopida. In the remaining Podocopa it is common to glue the eggs to a firm surface, like vegetation or the substratum. These eggs are often resting eggs, and remain dormant during desiccation and extreme temperatures, only hatching when exposed to more favorable conditions. Species adapted to vernal pools can reach sexual maturity in just 30 days after hatching. There is no larval stage or metamorphosis (direct development). Instead they hatch from the egg as juveniles with the bivalved carapace and at least three functional limbs. As the juvenile grows through a series of molts they acquire more limbs and develop further the already existing ones. They reach sexual maturity in the final instar and then never molts again. The number of instars they go through before adulthood varies. In Podocopa it is eight or nine (but family Entocytheridae and suborder Bairdiocopina has only seven), the Halocyprida goes through six or seven, and Myodocopida only four to six. They are able to produce several offspring many times as adults (iteroparity).

Predators
A variety of fauna prey upon ostracods in both aquatic and terrestrial environments. An example of predation in the marine environment is the action of certain Cytherocopina in the cuspidariid clams in detecting ostracods with cilia protruding from inhalant structures, thence drawing the ostracod prey in by a violent suction action. Predation from higher animals also occurs; for example, amphibians such as the rough-skinned newt prey upon certain ostracods.

Bioluminescence
Some ostracods, such as Vargula hilgendorfii, have a light organ in which they produce luminescent chemicals. These ostracods are called "blue sand" or "blue tears" and glow blue in the dark. Their bioluminescent properties made them valuable to the Japanese during World War II, when the Japanese army collected large amounts from the ocean to use as a convenient light for reading maps and other papers at night. The light from these ostracods, called umihotaru in Japanese, was sufficient to read by but not bright enough to give away troops' position to enemies. Bioluminescence has evolved twice in ostracods; once in Cypridinidae, and once in Halocyprididae. In bioluminescent Halocyprididae a green light is produced within carapace glands, and in Cypridinidae a blue light is produced and extruded from the upper lip. Most species use the light as predation defense, but the male of at least 75 known species of the Cypridinidae, restricted to the Caribbean, use pulses of light to attract females. Some species are the opposite where the females use pulses of light to attract males. This is seen in one example such as the glow worm. This bioluminiscent courtship display has only evolved once in ostracods, in a cypridinid group named Luxorina that originated at least 151 million years ago. Ostracods with bioluminescent courtship show higher rates of speciation than those who simply use light as protection against predators. The male will continue to swim after releasing its small ball of bioluminescent mucus, but the female is able to read the display to pinpoint the male's location. In one species hundreds of thousands of males synchronize their light display, and when one male creates a pattern of light, the new pattern will spread out as the neighboring males repeat it.

Classification
Early work indicated that Ostracoda may not be monophyletic, and early molecular phylogeny was ambiguous on this front. Recent combined analyses of molecular and morphological data suggested monophyly in analyses with broadest taxon sampling, but this monophyly had no or very little support (Fig. 1 - bootstrap 0, 17 and 46, often values above 95 are considered sufficient for the taxon support).

Class Ostracoda is divided into following living clades:
 * Subclass Myodocopa
 * Order Myodocopida
 * Suborder Myodocopina
 * Superfamily Cypridinoidea (1 family)
 * Superfamily Cylindroleberidoidea (1 family)
 * Superfamily Sarsielloidea (3 families)
 * Order Halocyprida
 * Suborder Halocypridina
 * Superfamily Thaumatocypridoidea (1 family)
 * Superfamily Halocypridoidea (1 family)
 * Suborder Cladocopina
 * Superfamily Cladocopoidea (1 family)
 * Subclass Podocopa
 * Order Palaeocopida
 * Suborder Kirkbyocopina
 * Superfamily Puncioidea (1 family)
 * Order Platycopida
 * Suborder Platycopina
 * Superfamily Cytherelloidea (1 family)
 * Order Podocopida
 * Suborder Cytherocopina
 * Superfamily Cytheroidea (27 families)
 * Superfamily Terrestricytheroidea (1 family)
 * Suborder Cypridocopina
 * Superfamily Macrocypridoidea (1 family)
 * Superfamily Pontocypridoidea (1 family)
 * Superfamily Cypridoidea (4 families)
 * Suborder Darwinulocopina
 * Superfamily Darwinuloidea (1 family)
 * Suborder Bairdiocopina
 * Superfamily Bairdioidea (3 families)
 * Suborder Sigilliocopina
 * Superfamily Sigillioidea (1 family)

title: Ostracod


text:
Adam's Mark

Adam's Mark Hotels & Resorts was a chain of upscale hotels in the United States. The company was headquartered in the HBE Corporation offices in Creve Coeur, Missouri, in Greater St. Louis. Fred Kummer founded the chain in the early 1970s, as well as its parent, HBE Corp.

History
In the late 1990s and early 2000s, Adams Mark faced several civil, state, and federal lawsuits for racial discrimination against Black customers. It was the first hotel chain, in its entirety, to face a United States Justice Department inquiry into racial discrimination for violations of the Civil Rights Act of 1964.

In the 1990s, Adams Mark settled multimillion-dollar racial discrimination lawsuits involving employees and consumers against individual hotels in Indianapolis and St. Louis.

In December 1999, five African–American hotel guests brought a class action lawsuit against the hotel chain after attending the Black College Reunion in Daytona Beach, Florida in 1999. The suit alleged that Adams Mark "charged black guests higher rates, required them to wear orange wrist bands and prohibited black visitors." Additionally, the claimants reported that "rooms rented to blacks had been 'stripped down' and lacked such basic amenities as telephones and maid service; pictures had been removed from the walls and room mini-bars were locked." The Justice Department agreed with the claimants in a nonmonetary settlement, finding that Adams Mark engaged in racial discrimination by "charging Black customers higher prices than Whites and segregating Black customers in less desirable rooms as part of a corporate pattern of discrimination."

The suit, and subsequent 17-month boycott of the chain called by the NAACP, was settled out of court for $8 million in 2000.

In July 2015, new allegations of racism against Adams Mark surfaced. The Daily Kos reported, "A white hotel manager of the Adams Mark Hotel in Kansas City, hung a black slave doll from the doorway of the office with a garbage bag in an apparent mocking of the death of Sandra Bland." Tweets about the incident documented a photograph of the doll hanging by a "white plastic bag noose" around her neck.

Hotels
While once numbering more than 20 large hotels, the chain, because of financial difficulties and changing corporate strategies, sold all of its properties during the 2000s.

 * In May, 2004, the Houston location, in the Westchase district, was rebranded as a Marriott.
 * In June, 2004, the Tulsa location was sold and rebranded as a Hyatt.
 * The Memphis Adam's Mark, originally built in 1975 as the Hyatt Regency Memphis, was sold in 2003, to a joint venture of Dallas-based Crow Holdings, manager of the real estate holdings of the Trammell Crow family, and Wilton D. 'Chick' Hill, the president of Memphis-based Davidson Hotel Co. The hotel underwent a $12 million renovation and reopened as the Hilton Memphis Hotel in 2005.
 * On October 3, 2004, the Adam's Mark at Clearwater Beach in Clearwater, Florida closed due to hurricane damage. It was demolished by implosion on October 8 the next year and the Opal Sands Resort opened on the site in February 2016.
 * In November 2004, Target Corporation purchased the Philadelphia Adam's Mark (opened in 1965 as a Holiday Inn) closing the 23-story building permanently to make way for a new Target store. On July 11, 2006, an unexpected collapse on the north side of the main tower trapped a construction worker helping to demolish the building. The new Target opened on the site in late 2007.
 * In 2005, Chartres Hospitality purchased the 966-room Adam's Mark in Jacksonville, Florida, which it converted to the Hyatt Regency Jacksonville Riverfront after a multimillion-dollar renovation.
 * The Florida Mall in Orlando, Florida contained an Adam's Mark which has since been rebranded as The Florida Mall Hotel.
 * The Adam's Mark in Dallas was built in 1959 as Southland Center, a multi-tower complex including an office building and the Sheraton-Dallas Hotel. The entire complex was converted into one enormous hotel, run by Adam's Mark, in the 1990s. In July 2006, the hotel completed a $30 million renovation and opened the "Tower Royale by Adam's Mark", a luxury 500-room hotel within a hotel. The hotel was home to many conventions such as Project A-Kon. In 2007, it was sold and reflagged as the Sheraton Dallas Hotel.
 * The Adam's Mark in Charlotte was built as the Sheraton Center in 1973 and became the Adam's Mark in 1984. It was sold to the Chetrit Group in 2005 and reopened as The Blake, a boutique hotel. It was converted into two separate hotels in 2013, each occupying one tower. After a $20 million renovation, one tower again became a Sheraton Hotel in August 2013, while the other tower opened as a Le Méridien Hotel in January 2014.
 * The Denver property, opened in 1961 as the Denver Hilton, designed by Araldo Cossutta and I.M. Pei, was also a Radisson before joining the chain in 1995. In 2008, it was reflagged as a Sheraton Hotel.
 * The St. Louis hotel became a Hyatt Regency in the spring of 2008, with Chartres Lodging Group spending at least $63 million to renovate the property.
 * In late August 2009, the Adam's Mark Indianapolis was re-flagged as the Wyndham Indianapolis West Hotel.
 * By 2010, the chain had dwindled to just one property, in Buffalo, New York, built as the Buffalo Hilton in 1978. Visions Hotels LLC, of Corning, New York, operator of several smaller size hotels in the Upstate New York region, purchased the property in February 2009 for $7.5 Million. By 2018 this hotel was purchased by developer Harry Stinson. Following renovations and upgrades, the hotel was renamed the Buffalo Grand Hotel.
 * The last remaining hotel to bear the Adam's Mark name, in Kansas City, Missouri was originally opened in 1974 as the Sheraton-Royal Hotel. It later became an Adam's Mark, then a Clarion Hotel in 2004, then a Sheraton again in 2007, then a Holiday Inn in 2009, then in April 2015 an Adam's Mark again. The hotel is near the Truman Sports Complex, home of both the Kansas City Chiefs and Royals. The hotel closed "indefinitely" in March 2020 due to the COVID-19 pandemic and was purchased by Community Builders of Kansas City later that year. They have since expressed plans to renovate the building into mixed-income housing or a sports training facility.

title: Adam's Mark