Flint is a hard, sedimentary cryptocrystalline form of the mineral quartz, categorized as a variety of chert. It occurs chiefly as nodules and masses such as chalks and limestones. Inside the nodule, flint is dark grey, green, white or brown in colour, has a glassy or waxy appearance. A thin layer on the outside of the nodules is different in colour white and rough in texture. From a petrological point of view, "flint" refers to the form of chert which occurs in chalk or marly limestone. "common chert" occurs in limestone. Flint is durable and can be found along streams and beaches, its use to make stone tools dates back millions of years. Due to some properties of flint it breaks into sharp edged pieces making it useful for knife blades and other sharp tools. During the Stone Age access to flint was so important for survival that people would travel or trade to obtain flint. Flint Ridge in eastern Ohio was an important source of flint and Native Americans extracted the flint from hundreds of quarries along the ridge.
This "Ohio Flint" was traded across the eastern United States and has been found as far west as the Rocky Mountains and south around the Gulf of Mexico. The exact mode of formation of flint is not yet clear, but it is thought that it occurs as a result of chemical changes in compressed sedimentary rock formations, during the process of diagenesis. One hypothesis is that a gelatinous material fills cavities in the sediment, such as holes bored by crustaceans or molluscs and that this becomes silicified; this hypothesis explains the complex shapes of flint nodules that are found. The source of dissolved silica in the porous media could be the spicules of silicious sponges. Certain types of flint, such as that from the south coast of England, contain trapped fossilised marine flora. Pieces of coral and vegetation have been found preserved like amber inside the flint. Thin slices of the stone reveal this effect. Puzzling giant flint formations known as paramoudra and flint circles are found around Europe but in Norfolk, England on the beaches at Beeston Bump and West Runton.
Flint sometimes occurs in large flint fields for example, in Europe. The "Ohio flint" is the official gemstone of Ohio state, it is formed from limey debris, deposited at the bottom of inland Paleozoic seas hundreds of millions of years ago that hardened into limestone and became infused with silica. The flint from Flint Ridge is found in many hues like red, pink, blue and gray, with the color variations caused by minute impurities of iron compounds. Flint was used in the manufacture of tools during the Stone Age as it splits into thin, sharp splinters called flakes or blades when struck by another hard object; this process is referred to as knapping. The process of making tools this way is called "flintknapping". In Europe, some of the best toolmaking flint has come from Belgium, the coastal chalks of the English Channel, the Paris Basin, Thy in Jutland, the Sennonian deposits of Rügen, Grimes Graves in England, the Upper Cretaceous chalk formation of Dobruja and the lower Danube, the Cenomanian chalky marl formation of the Moldavian Plateau and the Jurassic deposits of the Kraków area and Krzemionki in Poland, as well as of the Lägern in the Jura Mountains of Switzerland.
Flint mining became more common since the Neolithic. In 1938, a project of the Ohio Historical Society, under the leadership of H. Holmes Ellis began to study the flintknapping "methods and techniques" of Native Americans. Like past studies, this work involved experimenting with actual flintknapping techniques by creation of stone tools through the use of techniques like direct freehand percussion, freehand pressure and pressure using a rest. Other scholars who have conducted similar experiments and studies include William Henry Holmes, Alonzo W. Pond, Sir Francis H. S. Knowles and Don Crabtree; when struck against steel, a flint edge produces. The hard flint edge shaves off a particle of the steel that exposes iron, which reacts with oxygen from the atmosphere and can ignite the proper tinder. Prior to the wide availability of steel, rocks of pyrite would be used along with the flint, in a similar way; these methods are popular in woodcraft and amongst people practising traditional fire-starting skills.
A major use of flint and steel was in the flintlock mechanism, used in flintlock firearms, but used on dedicated fire-starting tools. A piece of flint held in the jaws of a spring-loaded hammer, when released by a trigger, strikes a hinged piece of steel at an angle, creating a shower of sparks and exposing a charge of priming powder; the sparks ignite the priming powder and that flame, in turn, ignites the main charge, propelling the ball, bullet, or shot through the barrel. While the military use of the flintlock declined after the adoption of the percussion cap from the 1840s onward, flintlock rifles and shotguns remain in use amongst recreational shooters. Flint and steel used to strike sparks were superseded by ferrocerium; this man-made material, when scraped with any hard, sharp edge, produces sparks that are much hotter than obtained with natural flint and steel, allowing use of a wider range of tinders. Because it can produce sparks when wet and can start fires
The Deptford culture was an archaeological culture in the United States characterized by the appearance of elaborate ceremonial complexes, increasing social and political complexity, mound burial, permanent settlements, population growth, an increasing reliance on cultigens. Deptford is named for the Deptford area near Georgia; the culture is defined by the presence of sand-tempered pottery decorated with the impressions of carved wooden paddles that were pressed against the vessels before they were fired. The sand-tempering distinguishes Deptford ceramics from the fiber-tempered ceramics of the late-Archaic Stallings Island/St. Simons and Norwood cultures that preceded it. Other contemporary cultures of the southeastern United States produced paddle decorated ceramics; the Deptford culture was oriented to the coast. From northern Georgia it spread along the Atlantic coast, reaching Cape Fear, North Carolina to the north and the mouth of the St. Johns River to the south; the Deptford culture spread along the Gulf of Mexico coast, reaching from the Perdido River on the western border of Florida to Tampa Bay on the lower west coast of Florida.
Deptford culture appeared in Florida around 500 BCE. The Deptford culture in the Gulf region evolved into the Swift Creek and Santa Rosa-Swift Creek cultures around 200 CE, while the culture in the Atlantic coastal region continued until about 700. In the eastern Florida Panhandle the Deptford culture has been divided into an early Deptford period, in which fiber-tempered and Deptford series ceramics are found together, a middle Deptford period, with only Deptford series ceramics present, a late Deptford period with both Deptford series and Swift Creek series ceramics present. Archaeological sites associated with the Deptford culture include: Tar River, North Carolina G. S. Lewis-West site, middle Savannah River Brewton Hill site, eastern Savannah, Georgia Dulany site, eastern Savannah Irene site, northwest of Savannah Refuge site, north of Savannah Meldrim site, southeast of Savannah Haven Home site, southwest of Savannah The Florida Panhandle from the Perdido River to the Aucilla River.
Hawkshaw site, in Pensacola, Florida The Block-Sterns site, Lake Lafayette, Florida Site 8LE484 on the northern shore of Lake Miccosukee, Leon County, FloridaThe sites in Leon County represent significant inland Deptford period sites. The Gulf coast of Florida from the Aucilla River to the Anclote River, extending 15 miles to 20 miles inland. Bird Island, near Horseshoe Beach, Florida Garden Patch, near Horseshoe Beach, Florida Cat Island, north of the mouth of the Suwannee River Little Bradford Island, in the mouth of the Suwannee River Sites 8LV75 and 8LV76 on Deer Island, between the mouth of the Suwannee River and Cedar Key, Florida Shell Mound, north of Cedar Key Palmetto Mound, north of Cedar Key Richards Island, north of Cedar Key North Key, in the Cedar Keys Seahorse Key, in the Cedar Keys Crystal River site, FloridaMany Deptford culture sites along the Gulf coast may now be under water, or eroded by rising water levels, as the sea level along the coast of the Florida Panhandle has risen 80 inches in the last 2,000 years.
Early Deptford ceramics appear to have been developed in Georgia around 2,600 years ago out of the Early Woodland Refuge phase, spread north into South Carolina and North Carolina and south into Florida. Deptford ceramics continued to be made and found on Middle Woodland sites in the southeastern U. S. until about 600 BCE. Occupation for the Atlantic coastal plain of Georgia and the Carolinas seems to have followed a seasonal pattern of winter shellfish camps on the coast inland occupation during the spring and summer for deer hunting, fall for nut gathering. From the Early through the Middle Woodland periods, the extensive, low-lying coastal environment of the South Atlantic coast, stretching from North Carolina to northern Florida, was used by numerous Deptford hunter-gatherer bands who lived seasonally within a variety of ecosystems and took advantage of seasonally available foods. Along the Gulf Coast, the Deptford culture continued the seasonal existence throughout the Middle Woodland.
Settlements in this geographical area lacked permanence of occupation, although the cultures here participated in the Hopewellian trading network to a limited extent and constructed numerous low sand burial mounds. These sand burial mounds along coastal Georgia and Florida, as well as in the Carolinas, are believed to represent local lineage burial grounds rather than the resting place of an elite individual. In northwestern Florida, the Early Woodland Deptford culture evolved in place to become the Swift Creek and Santa Rosa-Swift Creek cultures. Trade items recovered from burial mounds include copper panpipes, ear ornaments, stone plummets, stone gorgets; these show this area's incorporation within the Hopewellian Interaction Sphere by about 1,900 years ago. McFadden, Paulette S.. "Archaeological Investigations at Bird Island, Dixie County, Florida". University of Florida Laboratory of Southeastern Archaeology. Technical Report 14. Retrieved May 25, 2012. Milanich, Jerald T.. "The Southeastern Deptford Culture: a Preliminary Definition".
Bureau of Historic Sites and Properties. 3: 51–63. Retrieved 14 May 2012. Milanich, Jerald T.. Archaeology of Precolumbian Florida. Gainesville, Florida: University Press of Florida. ISBN 0-8130-1273-2. Monés, Micah P..
In the sequence of cultural stages first proposed for the archaeology of the Americas by Gordon Willey and Philip Phillips in 1958, the Lithic stage was the earliest period of human occupation in the Americas, as post-glacial hunters and collectors spread through the Americas. The stage derived its name from the first appearance of Lithic flaked stone tools; the term Paleo-Indian is an alternative indicating much the same period. This stage was conceived of as embracing two major categories of stone technology: unspecialized and unformulated core and flake industries, with percussion the dominant and only technique employed, industries exhibiting more advanced "blade" techniques of stoneworking, with specialized fluted or unfluted lanceolate points the most characteristic artifact types. Throughout South America, there are stone tool traditions of the lithic stage, such as the "fluted fishtail" that reflect localized adaptations to the diverse habitats of the continent; the indications and timing of the end of the Lithic stage vary between regions.
The use of textiles, fired pottery and start of the gradual replacement of hunter gatherer lifestyles with the use of agriculture and domesticated animals would all be factors. End dates are around 5,000 to 3,000 BC in many areas; the Archaic stage is the most used term for the succeeding stage, but in the periodization of pre-Columbian Peru the Cotton Pre-Ceramic may be used, as in the Norte Chico civilization cultivated cotton seems to have been important in economic and power relations, from around 3,200 BC. One of the leading figures is Alex Krieger who has documented hundreds of sites that have yielded crude, percussion-flaked tools; the most convincing evidence for a lithic stage is based upon data recovered from sites in South America where such crude tools have been found and dated to more than 20,000 years ago. In North America, the time encompasses the Paleo-Indian period that subsequently is divided into more specific time terms such as Early Lithic stage or Early Paleo-Indians and Middle Paleo-Indians or Middle Lithic stage.
Examples include the Clovis culture and Folsom tradition groups. The Lithic stage was followed by the Archaic stage. 12,340 BCE–10,800 BCE: a stone-lined hearth and coprolites left in Paisley Caves, Oregon 10,200 BCE: Cooper Bison skull is painted with a red zigzag in present-day Oklahoma, becoming the oldest known painted object in North America. 9500 BC: Cordilleran and Laurentide ice sheets retreat enough to open a habitable ice-free corridor through Canada along the eastern flank of the Rocky Mountains. 9500 BC: People craft early Clovis spear points and skin scrapers from rock in New Mexico. 9250–8950 BC: Clovis points - thin, fluted projectile points created using bifacial percussion flaking - are created by Clovis culture peoples in the Plains and Southwestern North America 9001 BC: Archaeological materials found on the Channel Islands of California and in coastal Peru. 9000 BC: Archaeological materials found on Channel Islands off the California coast 9000 BC: Human settlers arrive in the Great Basin with its cool, wet prevailing climate 9000–8900 BC: The Folsom culture in New Mexico leaves Bison bones and stone spear points.
8700 BC: Human settlement reaches the Northwestern Plateau region. 8000 BC: The last glacial ends, causing sea levels to rise and flood the Beringia land bridge, closing the primary migration route from Siberia. 8000 BC: Sufficient rain falls on the American Southwest to support many large mammal species--mammoth, a bison species-—that soon go extinct. 8000 BC: Native Americans leave documented traces of their presence in every habitable corner of the Americas, including the American Northeast, the Pacific Northwest, a cave on Prince of Wales Island in the Alexander archipelago of southeast Alaska following these game animals. 8000 BC: Hunters in the American Southwest both use the atlatl. 8000 BC: Sufficient rain falls on the American Southwest to support many large mammal species, such as mammoth, a bison species-—that soon go extinct. 8000 BC: Hunters in the American Southwest use the atlatl. Times from the 8000 BC to about 3000 BC may be classified as part of the lithic stage or of an archaic stage, depending on authority and on region.
7500 BC: Early basketry. 7560—7370 BC: Kennewick Man dies along the shore of the Columbia River in Washington State, leaving one of the most complete early Native American skeletons. 7000 BC: Northeastern peoples depend on deer and wild grains as the climate warms. 7000 BC: Native Americans in Lahontan Basin, Nevada mummify their dead to give them honor and respect, evidencing deep concern about their treatment and condition. 6500 BC–200 AD: The San Dieguito-Pinto tradition and Chihuahua Tradition flourish in southern California, the Southwest, northwestern Mexico. 6000 BC: Ancestors of Penutian-speaking peoples settle in the Northwestern Plateau. 6000 BC: Nomadic hunting bands roam Subarctic Alaska following herds of caribou and other game animals. 6000 BC: Aleuts begin to arrive in the Aleutian Islands. 5700 BC: Cataclysmic eruption of Mount Mazama in Oregon. 5500 BC–500 AD Oshara Tradition, a Southwestern Archaic Tradition, arises in north-central New Mexico, the San Juan Basin, the Rio Grande Valley, southern Colorado, southeastern Utah.
Natives of the Northwestern Plateau begin to rely on salmon runs. 5000 BC: Early cultivation of food crops began in Mesoamerica. 5000 BC: Native Americans in the Pacific Northwest from Alaska to California develop a fishing economy, with salmon as a staple. 5000 BC: The Old Copper Culture of the Great Lakes area hammers the metal into various tools and ornaments, such as knives, awls, bracelets and pendants. Archaeology of the Amer
Caborn-Welborn was a prehistoric North American culture defined by archaeologists as a Late Mississippian cultural manifestation that grew out of – or built upon the demise of – the Angel chiefdom located in the territory of southern present-day Indiana. Caborn-Welborn developed around 1400 and seems to have disappeared around 1700; the Caborn-Welborn culture was the last Native American occupation of southern Indiana before European contact. It remains unclear; the Caborn-Welborn culture is a cluster of more than 80 sites located on ridges along the Wabash and Ohio rivers from Geneva, Kentucky to the mouth of the Saline River. Most are concentrated near the confluence of the Wabash rivers; the sites range in size from 0.6 acres to 35 acres for the larger villages. Most sites are located on the higher flood plain ridges situated near sloughs and swamps; the Ohio River floodplain of this region has an extensive system of natural levees which parallel the river, with sloughs and swampy areas in between the levees.
Ashworth Archaeological Site – Located in Posey County and placed on the National Historic Register in 1985. Bone Bank Site – The site was a large village on the Wabash River in Posey County, it was nicknamed "Bone Bank" for the large number of remains of graves washed out of the site in the 19th century. It was established early in the Caborn-Welborn phase, about 1400. Hovey Lake-Klein Archeological Site – The site is located on the west bank of a backwater lake near the Ohio River, it was established about 1400. Murphy Archaeological Site – Located in Posey County and placed on the National Historic Register in 1975. Known as the Sullivan Farm Site and the Mouth-of-the-Wabash Site. Slack Farm Site – A large village near the mouth of the Wabash River in Union County, Kentucky. Welborn Village Archeological Site known as the Murphy's Landing Site – Located in Posey County. An internal temporal subdivision for the Caborn-Welborn culture, based on ceramic decorative attributes and the presence of European trade goods.
Pottery made by the Caborn-Welborn women was built up from strips of clay, smoothed out by the potter, much like other pottery in the Eastern America area, where the potters wheel was unknown. Common vessel shapes include jars, pans and funnels. Most jars tend to have rims with rounded necks and strap handles; the majority of the pottery found at Caborn-Welborn sites are of the kinds known as Mississippian Plain and Bell Plain, which are varieties common to most Mississippian cultures throughout the Ohio and Mississippi River valleys. It was buff colored, contains large fragments of ground mussel shell as a tempering agent, is not as smooth and polished as other varieties. Certain unique kinds of pottery and decorations define the Caborn-Welborn people as distinct from other cultures. Caborn-Welborn Decorated, Kimmswick Fabric Impressed, Kimmswick Plain are varieties which are present in greater frequencies in Caborn-Welborn sites, are hallmarks of the culture. Effigy jars, both of humans and animals, are common in Caborn-Welborn sites.
Some have a human or animal head and sometimes a tail attached to the rim, others are shaped into the forms of heads, with attached clay lugs to represent limbs. Caborn-Welborn Decorated, the most found decorated ceramic style, is characterized by incised or punctated lines on the shoulders of the jar forms. Other less common varieties found are indicative of continuity from preceding Lower Ohio Valley cultures and contact with the wider Mississippian world the Central Mississippi valley and the Oneota culture; these types include Old Town Red, O'Byam Incised/Engraved, Manly Punctate, Angel/Kincaid Negative Painted, Beckwith Incised, Barton Incised, Ranch Incised-Like, Parkin Punctate, Campbell Punctate, Walls Engraved, Vernon Paul Applique. The people of Caborn-Welborn were intensely involved in maize agriculture, as well as other food crops originating in the Americas, such as beans, squash and gourds; the addition of beans to their diet came after the demise of the Angel Phase peoples thought to have preceded the Caborn-Welborn.
It would have been a valuable source of protein to add to their maize-rich diet. Maize lacks the amino acids lysine and tryptophan, which the body needs to make proteins and niacin, but beans contain both, they collected local wild foodstuffs, including a variety of nuts such as hickory, black walnut and acorns, as well as fleshy fruits and berries such as persimmon and plums. The hunting of whitetail deer, squirrel, turkey and beaver added vital protein to their diet. But, unlike other Mississippian peoples in the central Mississippi Valley, they did not eat quantities of fish and waterfowl as part of their diet. By the final phase of Caborn-Welborn culture, European trade items began to be included among grave goods; these included copper and brass tubes, glass beads, bracelets. This is not indicative of direct European contact, however; the items could have made their way to the Caborn-Welborn area by the native traders along the routes which had brought exotic materials such as marine shells and native copper from other regions to the area for centuries.
But with the traders contracted and carried European diseases such as smallpox and measles, which penetrated the American continents far in advance of European-manned expeditions. With little or no immunity to the new European diseases, many Native cultures died or were disrupted before the Europeans made direct physical contact with them. The
Fort Walton culture
The Fort Walton culture is the term used by archaeologists for a late prehistoric Native American archaeological culture that flourished in southeastern North America from 1200~1500 CE and is associated with the historic Apalachee people. The Fort Walton culture was named by archaeologist Gordon Willey for the Fort Walton Mound site near Fort Walton Beach, based on his work at the site. Through more work in the area archaeologist have now come to believe the Ft. Walton site was built and used by people of the contemporaneous Pensacola culture; the peoples of the Ft. Walton culture used sand, grog, or combinations of these materials as tempering agents in their pottery, whereas the Pensacola culture peoples used the more typical Mississippian culture shell tempering for their pottery. Using this unique combination of sand/grit/grog tempering as its criterion Fort Walton culture is now defined within the geographical area stretching from the Aucilla River in the east to a Pensacola–Fort Walton transitional area around Choctawhatchee Bay in the west and north into the interior of south Alabama and Georgia, 107 miles up the Apalachicola River and 50 miles up the Chattahoochee River.
1000 to 1200 CE local Weeden Island peoples began adapting and adopting intensive maize agriculture, the building of platform mounds for ceremonial and religious purposes and making a new variety of ceramics, changes influenced by contact with the major Mississippian culture centers to the north and west. Early archaeologists thought that the Fort Walton culture represented the intrusion of peoples from Mexico or Mississippian cultures from the northwest replacing the indigenous Weeden Island peoples, but by the late 1970s this theory was discounted. Layouts and locations for Fort Walton sites are similar to other Mississippian culture sites, with the exception of sites in the Tallahassee Hills area which because of the local geography are located around lakes and swamps instead of rivers. Settlement types include single family homesteads, multi family hamlets, small single mound centers, large multimound centers; the hierarchical settlement patterns suggests. By the Late Fort Walton period increased contact with Lamar Phase peoples from central Georgia saw another change in styles of decoration and manufacture of ceramics.
This new phase is known as the Leon-Jefferson culture. This period sees the collapse of the chiefdoms as aboriginal populations declined following contact with European explorers and colonizers, such as the Hernando de Soto Expedition in 1539; the Fort Walton and Leon-Jefferson peoples are the direct ancestors of the Apalachee peoples. The Lake Jackson Mounds site in Leon County is the largest known ceremonial center of the Fort Walton culture, although there are eight other known ceremonial sites in the Apalachee Province, it was occupied during the entire Fort Walton period, but abandoned at about 1500 CE when the capital of the chiefdom was moved to nearby Anhaica, the capital when the de Soto entrada encamped there in the winter of 1539. Another large site located nearby is the Velda Mound, occupied from 1450 to 1625. Other sites include the Yon Mound and Village Site in Liberty County, the Thick Greenbriar Site in Jackson County. Woodville Karst Plain Project Gabrielle Shahramfar. Determining Fort Walton burial patterns and their relationship within the greater Mississippian world.
University of South Florida
Iron oxides are chemical compounds composed of iron and oxygen. All together, there are sixteen known iron oxyhydroxides. Iron oxides and oxide-hydroxides are widespread in nature, play an important role in many geological and biological processes, are used by humans, e.g. as iron ores, catalysts, in thermite and hemoglobin. Common rust is a form of iron oxide. Iron oxides are used as inexpensive, durable pigments in paints and colored concretes. Colors available are in the "earthy" end of the yellow/orange/red/brown/black range; when used as a food coloring, it has E number E172. Oxide of FeIIFeO: iron oxide, wüstite FeO2: iron dioxide Mixed oxides of FeII and FeIIIFe3O4: Iron oxide, magnetite Fe4O5 Fe5O6 Fe5O7 Fe25O32 Fe13O19 Oxide of FeIIIFe2O3: iron oxide α-Fe2O3: alpha phase, hematite β-Fe2O3: beta phase γ-Fe2O3: gamma phase, maghemite ε-Fe2O3: epsilon phase iron hydroxide iron hydroxide, akaganéite, feroxyhyte, ferrihydrite, or 5 Fe 2 O 3 ⋅ 9 H 2 O, better recast as FeOOH ⋅ 0.4 H 2 O high-pressure FeOOH schwertmannite green rust Several species of bacteria, including Shewanella oneidensis, Geobacter sulfurreducens and Geobacter metallireducens, metabolically utilize solid iron oxides as a terminal electron acceptor, reducing Fe oxides to Fe containing oxides.
Under conditions favoring iron reduction, the process of iron oxide reduction can replace at least 80% of methane production occurring by methanogenesis. This phenomenon occurs in a nitrogen-containing environment with low sulfate concentrations. Methanogenesis, an Archaean driven process, is the predominate form of carbon mineralization in sediments at the bottom of the ocean. Methanogenesis completes the decomposition of organic matter to methane; the specific electron donor for iron oxide reduction in this situation is still under debate, but the two potential candidates include either Titanium or compounds present in yeast. The predicted reactions with Titanium serving as the electron donor and phenazine-1-carboxylate serving as an electron shuttle is as follows: Ti-cit + CO2 + 8H+ → CH4 + 2H2O + Ti + cit ΔE = –240 + 300 mV Ti-cit + PCA → PCA + Ti + cit ΔE = –116 + 300 mV PCA + Fe3 → Fe2+ + PCA ΔE = –50 + 116 mV Note: cit = citrate. Titanium is oxidized to Titanium; the reduced form of PCA can reduce the iron hydroxide.
On the other hand when airborne, iron oxides have been shown to harm the lung tissues of living organisms by the formation of hydroxyl radicals, leading to the creation of alkyl radicals. The following reactions occur when Fe2O3 and FeO, hereafter represented as Fe3+ and Fe2+ iron oxide particulates accumulate in the lungs. O2 + e− → O2• –The formation of the superoxide anion is catalyzed by a transmembrane enzyme called NADPH oxidase; the enzyme facilitates the transport of an electron across the plasma membrane from cytosolic NADPH to extracellular oxygen to produce O2• –. NADPH and FAD are bound to cytoplasmic binding sites on the enzyme. Two electrons from NADPH are transported to FAD which reduces it to FADH2. One electron moves to one of two heme groups in the enzyme within the plane of the membrane; the second electron pushes the first electron to the second heme group so that it can associate with the first heme group. For the transfer to occur, the second heme must be bound to extracellular oxygen, the acceptor of the electron.
This enzyme can be located within the membranes of intracellular organelles allowing the formation of O2• – to occur within organelles. 2O2• – + 2 H+ → H2O2 + O2 The formation of hydrogen peroxide can occur spontaneously when the environment has a lower pH at pH 7.4. The enzyme superoxide dismutase can catalyze this reaction. Once H2O2 has been synthesized, it can diffuse thro
University of Chicago
The University of Chicago is a private research university in Chicago, Illinois. Founded in 1890 by John D. Rockefeller, the school is located on a 217-acre campus in Chicago's Hyde Park neighborhood, near Lake Michigan; the University of Chicago holds top-ten positions in various international rankings. The university is composed of an undergraduate college as well as various graduate programs and interdisciplinary committees organized into five academic research divisions. Beyond the arts and sciences, Chicago is well known for its professional schools, which include the Pritzker School of Medicine, the Booth School of Business, the Law School, the School of Social Service Administration, the Harris School of Public Policy Studies, the Divinity School and the Graham School of Continuing Liberal and Professional Studies; the university has additional campuses and centers in London, Beijing and Hong Kong, as well as in downtown Chicago. University of Chicago scholars have played a major role in the development of many academic disciplines, including sociology, economics, literary criticism and the behavioralism school of political science.
Chicago's physics department and the Met Lab helped develop the world's first man-made, self-sustaining nuclear reaction beneath the viewing stands of university's Stagg Field, a key part of the classified Manhattan Project effort of World War II. The university research efforts include administration of Fermi National Accelerator Laboratory and Argonne National Laboratory, as well as the Marine Biological Laboratory; the university is home to the University of Chicago Press, the largest university press in the United States. With an estimated completion date of 2021, the Barack Obama Presidential Center will be housed at the university and include both the Obama presidential library and offices of the Obama Foundation; the University of Chicago has produced faculty members and researchers. As of 2018, 98 Nobel laureates have been affiliated with the university as professors, faculty, or staff, making it a university with one of the highest concentrations of Nobel laureates in the world. 34 faculty members and 18 alumni have been awarded the MacArthur "Genius Grant".
In addition, Chicago's alumni and faculty include 54 Rhodes Scholars, 26 Marshall Scholars, 9 Fields Medalists, 4 Turing Award Winners, 24 Pulitzer Prize winners, 20 National Humanities Medalists, 16 billionaire graduates and a plethora of members of the United States Congress and heads of state of countries all over the world. The University of Chicago was incorporated as a coeducational institution in 1890 by the American Baptist Education Society, using $400,000 donated to the ABES to match a $600,000 donation from Baptist oil magnate and philanthropist John D. Rockefeller, including land donated by Marshall Field. While the Rockefeller donation provided money for academic operations and long-term endowment, it was stipulated that such money could not be used for buildings; the Hyde Park campus was financed by donations from wealthy Chicagoans like Silas B. Cobb who provided the funds for the campus' first building, Cobb Lecture Hall, matched Marshall Field's pledge of $100,000. Other early benefactors included businessmen Charles L. Hutchinson, Martin A. Ryerson Adolphus Clay Bartlett and Leon Mandel, who funded the construction of the gymnasium and assembly hall, George C. Walker of the Walker Museum, a relative of Cobb who encouraged his inaugural donation for facilities.
The Hyde Park campus continued the legacy of the original university of the same name, which had closed in 1880s after its campus was foreclosed on. What became known as the Old University of Chicago had been founded by a small group of Baptist educators in 1856 through a land endowment from Senator Stephen A. Douglas. After a fire, it closed in 1886. Alumni from the Old University of Chicago are recognized as alumni of the present University of Chicago; the university's depiction on its coat of arms of a phoenix rising from the ashes is a reference to the fire and demolition of the Old University of Chicago campus. As an homage to this pre-1890 legacy, a single stone from the rubble of the original Douglas Hall on 34th Place was brought to the current Hyde Park location and set into the wall of the Classics Building; these connections have led the Dean of the College and University of Chicago and Professor of History John Boyer to conclude that the University of Chicago has, "a plausible genealogy as a pre–Civil War institution".
William Rainey Harper became the university's president on July 1, 1891 and the Hyde Park campus opened for classes on October 1, 1892. Harper worked on building up the faculty and in two years he had a faculty of 120, including eight former university or college presidents. Harper was an accomplished scholar and a member of the Baptist clergy who believed that a great university should maintain the study of faith as a central focus. To fulfill this commitment, he brought the Old University of Chicago's Seminary to Hyde Park; this became the Divinity School in the first professional school at the University of Chicago. Harper recruited acclaimed Yale baseball and football player Amos Alonzo Stagg from the Young Men's Christian Association training Shool at Springfield to coach the school's football program. Stagg was given a position on the first such athletic position in the United States. While coaching at the University, Stagg invented the numbered football jersey, the huddle, the lighted playing field.
Stagg is the namesake of the university's Stagg