A cell wall is a structural layer surrounding some types of cells, situated outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering mechanism. Cell walls are present in most prokaryotes (except mycoplasma bacteria), in algae, plants and fungi but rarely in other eukaryotes including animals.  A major function is to act as pressure vessels, preventing over-expansion of the cell when water enters.

The composition of cell walls varies between species and may depend on cell type and developmental stage. The primary cell wall of land plants is composed of the polysaccharides cellulose, hemicellulose and pectin. Often, other polymers such as lignin, suberin or cutin are anchored to or embedded in plant cell walls. Algae possess cell walls made of glycoproteins and polysaccharides such as carrageenan and agar that are absent from land plants. In bacteria, the cell wall is composed of peptidoglycan. The cell walls of archaea have various compositions, and may be formed of glycoprotein S-layers, pseudopeptidoglycan, or polysaccharides. Fungi possess cell walls made of the glucosamine polymer chitin. Unusually, diatoms have a cell wall composed of biogenic silica.

ប្រវត្តិសាស្ត្រ
A plant cell wall was first observed and named (simply as a "wall") by Robert Hooke in 1665. However, "the dead excrusion product of the living protoplast" was forgotten, for almost three centuries, being the subject of scientific interest mainly as a resource for industrial processing or in relation to animal or human health.

In 1804, Karl Rudolphi and J.H.F. Link proved that cells had independent cell walls. Before, it had been thought that cells shared walls and that fluid passed between them this way.

The mode of formation of the cell wall was controversial in the 19th century. Hugo von Mohl (1853, 1858) advocated the idea that the cell wall grows by apposition. Carl Nägeli (1858, 1862, 1863) believed that the growth of the wall in thickness and in area was due to a process termed intussusception. Each theory was improved in the following decades: the apposition (or lamination) theory by Eduard Strasburger (1882, 1889), and the intussusception theory by Julius Wiesner (1886).

In 1930, Ernst Münch coined the term apoplast in order to separate the "living" symplast from the "dead" plant region, the latter of which included the cell wall.

By the 1980s, some authors suggested replacing the term "cell wall", particularly as it was used for plants, with the more precise term "extracellular matrix", as used for animal cells, but others preferred the older term.

Properties

Cell walls serve similar purposes in those organisms that possess them. They may give cells rigidity and strength, offering protection against mechanical stress. In multicellular organisms, they permit the organism to build and hold a definite shape (morphogenesis). Cell walls also limit the entry of large molecules that may be toxic to the cell. They further permit the creation of stable osmotic environments by preventing osmotic lysis and helping to retain water. Their composition, properties, and form may change during the cell cycle and depend on growth conditions.

Rigidity of cell walls
In most cells, the cell wall is flexible, meaning that it will bend rather than holding a fixed shape, but has considerable tensile strength. The apparent rigidity of primary plant tissues is enabled by cell walls, but is not due to the walls' stiffness. Hydraulic turgor pressure creates this rigidity, along with the wall structure. The flexibility of the cell walls is seen when plants wilt, so that the stems and leaves begin to droop, or in seaweeds that bend in water currents. As John Howland explains:

The apparent rigidity of the cell wall thus results from inflation of the cell contained within. This inflation is a result of the passive uptake of water.

In plants, a secondary cell wall is a thicker additional layer of cellulose which increases wall rigidity. Additional layers may be formed by lignin in xylem cell walls, or suberin in cork cell walls. These compounds are rigid and waterproof, making the secondary wall stiff. Both wood and bark cells of trees have secondary walls. Other parts of plants such as the leaf stalk may acquire similar reinforcement to resist the strain of physical forces.

Permeability
The primary cell wall of most plant cells is freely permeable to small molecules including small proteins, with size exclusion estimated to be 30-60 kDa.  The pH is an important factor governing the transport of molecules through cell walls.

ការវិវត្តន៍

Cell walls evolved independently in many groups, even in the photosynthetic eukaryotes. In these lineages, the cell wall is closely related to the evolution of multicellularity, terrestrialization and vascularization.

Plant cell walls
The walls of plant cells must have sufficient tensile strength to withstand internal osmotic pressures of several times atmospheric pressure that result from the difference in solute concentration between the cell interior and external solutions. Plant cell walls vary from 0.1 to several µm in thickness.

ស្រទាប់

Up to three strata or layers may be found in plant cell walls:

The primary cell wall, generally a thin, flexible and extensible layer formed while the cell is growing.
The secondary cell wall, a thick layer formed inside the primary cell wall after the cell is fully grown. It is not found in all cell types. Some cells, such as the conducting cells in xylem, possess a secondary wall containing lignin, which strengthens and waterproofs the wall.
The middle lamella, a layer rich in pectins. This outermost layer forms the interface between adjacent plant cells and glues them together.

ការតែងនិពន្ធ
In the primary (growing) plant cell wall, the major carbohydrates are cellulose, hemicellulose and pectin. The cellulose microfibrils are linked via hemicellulosic tethers to form the cellulose-hemicellulose network, which is embedded in the pectin matrix. The most common hemicellulose  in the primary cell wall is xyloglucan. In grass cell walls, xyloglucan and pectin are reduced in abundance and partially replaced by glucuronarabinoxylan, another type of hemicellulose. Primary cell walls characteristically extend (grow) by a mechanism called acid growth, which involves turgor-driven movement of the strong cellulose microfibrils within the weaker hemicellulose/pectin matrix, catalyzed by expansin proteins. The outer part of the primary cell wall of the plant epidermis is usually impregnated with cutin and wax, forming a permeability barrier known as the plant cuticle.

Secondary cell walls contain a wide range of additional compounds that modify their mechanical properties and permeability. The major polymers that make up wood (largely secondary cell walls) include:
 cellulose, 35-50%
 xylan, 20-35%, a type of hemicellulose
 lignin, 10-25%, a complex phenolic polymer that penetrates the spaces in the cell wall between cellulose, hemicellulose and pectin components, driving out water and strengthening the wall.

Additionally, structural proteins (1-5%) are found in most plant cell walls; they are classified as hydroxyproline-rich glycoproteins (HRGP), arabinogalactan proteins (AGP), glycine-rich proteins (GRPs), and proline-rich proteins (PRPs). Each class of glycoprotein is defined by a characteristic, highly repetitive protein sequence. Most are glycosylated, contain hydroxyproline (Hyp) and become cross-linked in the cell wall. These proteins are often concentrated in specialized cells and in cell corners. Cell walls of the epidermis may contain cutin. The Casparian strip in the endodermis roots and cork cells of plant bark contain suberin. Both cutin and suberin are polyesters that function as permeability barriers to the movement of water. The relative composition of carbohydrates, secondary compounds and proteins varies between plants and between the cell type and age. Plant cells walls also contain numerous enzymes, such as hydrolases, esterases, peroxidases, and transglycosylases, that cut, trim and cross-link wall polymers.

Secondary walls - especially in grasses - may also contain microscopic silica crystals, which may strengthen the wall and protect it from herbivores.

Cell walls in some plant tissues also function as storage deposits for carbohydrates that can be broken down and resorbed to supply the metabolic and growth needs of the plant. For example, endosperm cell walls in the seeds of cereal grasses, nasturtium
and other species, are rich in glucans and other polysaccharides that are readily digested by enzymes during seed germination to form simple sugars that nourish the growing embryo.

Formation

The middle lamella is laid down first, formed from the cell plate during cytokinesis, and the primary cell wall is then deposited inside the middle lamella. The actual structure of the cell wall is not clearly defined and several models exist - the covalently linked cross model, the tether model, the diffuse layer model and the stratified layer model. However, the primary cell wall, can be defined as composed of cellulose microfibrils aligned at all angles. Cellulose microfibrils are produced at the plasma membrane by the cellulose synthase complex, which is proposed to be made of a hexameric rosette that contains three cellulose synthase catalytic subunits for each of the six units. Microfibrils are held together by hydrogen bonds to provide a high tensile strength. The cells are held together and share the gelatinous membrane called the middle lamella, which contains magnesium and calcium pectates (salts of pectic acid). Cells interact though plasmodesmata, which are inter-connecting channels of cytoplasm that connect to the protoplasts of adjacent cells across the cell wall.

In some plants and cell types, after a maximum size or point in development has been reached, a secondary wall is constructed between the plasma membrane and primary wall. Unlike the primary wall, the cellulose microfibrils are aligned parallel in layers, the orientation changing slightly with each additional layer so that the structure becomes helicoidal.  Cells with secondary cell walls can be rigid, as in the gritty sclereid cells in pear and quince fruit. Cell to cell communication is possible through pits in the secondary cell wall that allow plasmodesmata to connect cells through the secondary cell walls.

Fungal cell walls

There are several groups of organisms that have been called "fungi". Some of these groups (Oomycete and Myxogastria) have been transferred out of the Kingdom Fungi, in part because of fundamental biochemical differences in the composition of the cell wall.  Most true fungi have a cell wall consisting largely of chitin and other polysaccharides.  True fungi do not have cellulose in their cell walls.

True fungi
In fungi, the cell wall is the outer-most layer, external to the plasma membrane. The fungal cell wall is a matrix of three main components:
 chitin: polymers consisting mainly of unbranched chains of β-(1,4)-linked-N-Acetylglucosamine in the Ascomycota and Basidiomycota, or poly-β-(1,4)-linked-N-Acetylglucosamine (chitosan) in the Zygomycota. Both chitin and chitosan are synthesized and extruded at the plasma membrane.
 glucans: glucose polymers that function to cross-link chitin or chitosan polymers. β-glucans are glucose molecules linked via β-(1,3)- or β-(1,6)- bonds and provide rigidity to the cell wall while α-glucans are defined by α-(1,3)- and/or α-(1,4) bonds and function as part of the matrix.
 proteins: enzymes necessary for cell wall synthesis and lysis in addition to structural proteins are all present in the cell wall. Most of the structural proteins found in the cell wall are glycosylated and contain mannose, thus these proteins are called mannoproteins or mannans.

Other eukaryotic cell walls

សារាយ

Like plants, algae have cell walls. Algal cell walls contain either polysaccharides (such as cellulose (a glucan)) or a variety of glycoproteins (Volvocales) or both. The inclusion of additional polysaccharides in algal cells walls is used as a feature for algal taxonomy.

 Mannans: They form microfibrils in the cell walls of a number of marine green algae including those from the genera, Codium, Dasycladus, and Acetabularia as well as in the walls of some red algae, like Porphyra and Bangia.
 Xylans:
 Alginic acid: It is a common polysaccharide in the cell walls of brown algae.
 Sulfonated polysaccharides: They occur in the cell walls of most algae; those common in red algae include agarose, carrageenan, porphyran, furcelleran and funoran.

Other compounds that may accumulate in algal cell walls include sporopollenin and calcium ions.

The group of algae known as the diatoms synthesize their cell walls (also known as frustules or valves) from silicic acid (specifically orthosilicic acid, H4SiO4). The acid is polymerised intra-cellularly, then the wall is extruded to protect the cell. Significantly, relative to the organic cell walls produced by other groups, silica frustules require less energy to synthesize (approximately 8%), potentially a major saving on the overall cell energy budget and possibly an explanation for higher growth rates in diatoms.<ref>{{Cite journal | doi = 10.1093/plankt/12.6.1117 | author = Furnas, M. J. | year = 1990 | title = In situ growth rates of marine phytoplankton : Approaches to measurement, community and species growth rates | url = | journal = J. Plankton Res. | volume = 12 | issue = 6| pages = 1117–1151 }}</ref>

In brown algae, phlorotannins may be a constituent of the cell walls.

Water molds
The group Oomycetes, also known as water molds, are saprotrophic plant pathogens like fungi. Until recently they were widely believed to be fungi, but structural and molecular evidence has led to their reclassification as heterokonts, related to autotrophic brown algae and diatoms.  Unlike fungi, oomycetes typically possess cell walls of cellulose and glucans rather than chitin, although some genera (such as Achlya and Saprolegnia) do have chitin in their walls.  The fraction of cellulose in the walls is no more than 4 to 20%, far less than the fraction of glucans.  Oomycete cell walls also contain the amino acid hydroxyproline, which is not found in fungal cell walls.

Slime molds
The dictyostelids are another group formerly classified among the fungi. They are slime molds that feed as unicellular amoebae, but aggregate into a reproductive stalk and sporangium under certain conditions. Cells of the reproductive stalk, as well as the spores formed at the apex, possess a cellulose wall. The spore wall has been shown to possess three layers, the middle of which is composed primarily of cellulose, and the innermost is sensitive to cellulase and pronase.

Prokaryotic cell walls

Bacterial cell walls

Around the outside of the cell membrane is the bacterial cell wall. Bacterial cell walls are made of peptidoglycan (also called murein), which is made from polysaccharide chains cross-linked by unusual peptides containing D-amino acids. Bacterial cell walls are different from the cell walls of plants and fungi which are made of cellulose and chitin, respectively. The cell wall of bacteria is also distinct from that of Archaea, which do not contain peptidoglycan. The cell wall is essential to the survival of many bacteria, although L-form bacteria can be produced in the laboratory that lack a cell wall.  The antibiotic penicillin is able to kill bacteria by preventing the cross-linking of peptidoglycan and this causes the cell wall to weaken and lyse. The lysozyme enzyme can also damage bacterial cell walls.

There are broadly speaking two different types of cell wall in bacteria, called Gram-positive and Gram-negative. The names originate from the reaction of cells to the Gram stain, a test long-employed for the classification of bacterial species.

Gram-positive bacteria possess a thick cell wall containing many layers of peptidoglycan and teichoic acids. In contrast, Gram-negative bacteria have a relatively thin cell wall consisting of a few layers of peptidoglycan surrounded by a second lipid membrane containing lipopolysaccharides and lipoproteins. Most bacteria have the Gram-negative cell wall and only the Firmicutes and Actinobacteria (previously known as the low G+C and high G+C Gram-positive bacteria, respectively) have the alternative Gram-positive arrangement. These differences in structure can produce differences in antibiotic susceptibility, for instance vancomycin can kill only Gram-positive bacteria and is ineffective against Gram-negative pathogens, such as Haemophilus influenzae or Pseudomonas aeruginosa.

Archaeal cell walls
Although not truly unique, the cell walls of Archaea are unusual. Whereas peptidoglycan is a standard component of all bacterial cell walls, all archaeal cell walls lack peptidoglycan, with the exception of one group of methanogens. In that group, the peptidoglycan is a modified form very different from the kind found in bacteria.  There are four types of cell wall currently known among the Archaea.

One type of archaeal cell wall is that composed of pseudopeptidoglycan (also called pseudomurein).  This type of wall is found in some methanogens, such as Methanobacterium and Methanothermus.  While the overall structure of archaeal pseudopeptidoglycan superficially resembles that of bacterial peptidoglycan, there are a number of significant chemical differences. Like the peptidoglycan found in bacterial cell walls, pseudopeptidoglycan consists of polymer chains of glycan cross-linked by short peptide connections.  However, unlike peptidoglycan, the sugar N-acetylmuramic acid is replaced by N-acetyltalosaminuronic acid, and the two sugars are bonded with a β,1-3 glycosidic linkage instead of  β,1-4.  Additionally, the cross-linking peptides are L-amino acids rather than D-amino acids as they are in bacteria.

A second type of archaeal cell wall is found in Methanosarcina and Halococcus.  This type of cell wall is composed entirely of a thick layer of polysaccharides, which may be sulfated in the case of Halococcus.  Structure in this type of wall is complex and not fully investigated.

A third type of wall among the Archaea consists of glycoprotein, and occurs in the hyperthermophiles, Halobacterium, and some methanogens.  In Halobacterium, the proteins in the wall have a high content of acidic amino acids, giving the wall an overall negative charge.  The result is an unstable structure that is stabilized by the presence of large quantities of positive sodium ions that neutralize the charge.  Consequently, Halobacterium thrives only under conditions with high salinity.

In other Archaea, such as Methanomicrobium and Desulfurococcus, the wall may be composed only of surface-layer proteins, known as an S-layer. S-layers are common in bacteria, where they serve as either the sole cell-wall component or an outer layer in conjunction with polysaccharides. Most Archaea are Gram-negative, though at least one Gram-positive member is known.

Other cell coverings

Many protists and bacteria produce other cell surface structures apart from cell walls, external (extracellular matrix) or internal.Becker, B. The cell surface of flagellates . In: The Flagellates. Unity, diversity and evolution. Ed.: Barry S. C. Leadbeater and J. C. Green Taylor and Francis, London 2000. Many algae have a sheath or envelope of mucilage outside the cell made of exopolysaccharides. Diatoms build a frustule from silica extracted from the surrounding water; radiolarians, foraminiferans, testate amoebae and silicoflagellates also produce a skeleton from minerals, called test in some groups.  Many green algae, such as Halimeda'' and the Dasycladales, and some red algae, the Corallinales, encase their cells in a secreted skeleton of calcium carbonate.  In each case, the wall is rigid and essentially inorganic. It is the non-living component of cell. Some golden algae, ciliates and choanoflagellates  produces a shell-like protective outer covering called lorica. Some dinoflagellates have a theca of cellulose plates, and coccolithophorids have coccoliths.

An extracellular matrix is also present in metazoans. Its composition varies between cells, but collagens are the most abundant protein in the ECM.

សូមមើលផងដែរ
 Bacterial cell structure
 Plant cell

ឯកសារយោង

តំណភ្ជាប់ខាងក្រៅ

 Cell wall ultrastructure
 The Cell Wall

ជញ្ជាំងកោសិកា


Sir Alec Guinness,  (1914–2000) was an English actor. After an early career on the stage, Guinness was featured in several of the Ealing Comedies, including The Ladykillers and Kind Hearts and Coronets in which he played nine different characters. He is known for his six collaborations with David Lean: Herbert Pocket in Great Expectations (1946), Fagin in Oliver Twist (1948), Col. Nicholson in The Bridge on the River Kwai (1957, for which he won the Academy Award for Best Actor), Prince Faisal in Lawrence of Arabia (1962), General Yevgraf Zhivago in Doctor Zhivago (1965), and Professor Godbole in A Passage to India (1984). He is also known for his portrayal of Obi-Wan Kenobi in George Lucas' original Star Wars trilogy; for the original film, he was nominated for Best Supporting Actor at the 50th Academy Awards.

Theatre

Filmography

Notes and references

Sources

External links
 Alec Guinness at the British Film Institute

Male actor filmographies
British filmographies

Alec Guinness on stage and screen


The origin of birds is one of the most interesting questions in palaeontology and evolution. Birds evolved from theropod dinosaurs during the Mesozoic era.

Thomas Henry Huxley ("Darwin's bulldog"), who was a comparative anatomist, made a study of this nearly 150 years ago. He compared the first fossil bird, Archaeopteryx, with a small theropod dinosaur, Compsognathus. They are two fossils from the same place and time: the Solnhofen limestone in Bavaria, Germany. The strata come from the end of the Jurassic period, about 144 million years ago.

Huxley's papers on Archaeopteryx, and the origin of birds, were of great interest then, and still are. He showed that the two fossils were almost identical, except for the front limbs and feathers of Archaeopteryx.

He united reptiles and birds under the title of Sauropsida, and thought that birds had evolved from small carnivorous dinosaurs.

Modern ideas
All palaeontologists since Huxley agreed that Archaeopteryx evolved from reptiles, but many thought it was derived from an earlier type than dinosaurs. It took a long time before they agreed with Huxley. Almost all now think that early members of a group of small carnivorous dinosaur were ancestral to birds.

The group most favoured as ancestral is the Paraves or Eumaniraptora, which includes the dromaeosaurs and the troodonts. The dromaeosaurs include Velociraptor and Deinonychus but, of course, it would have been an earlier type of dromaeosaur, perhaps from the lower Jurassic. Dromaeosaurs have several traits we used to think were special to birds: hollow bones with holes for air-sacs, limbs with many bones either lost or fused, clavicles fused into wishbones, and feathers.

The discovery of feathered dinosaurs and birds in the Lower Cretaceous of China was what finally convinced palaeontologists. What seems to have happened is this. Theropod dinosaurs evolved feathers for heat regulation rather than flight. From then, a small group began to use them for primitive flight. This group is represented in the Jurassic by Archaeopteryx and Anchiornis.

Mosaic of old and new
Huxley had pointed out that Archaeopteryx was a mixture of reptile and bird features. Without the feathers and arms, its skeleton looked just like that of Compsognathus. We now know its bone growth physiology was much slower than modern birds, and more like that of its dinosaur ancestors. This means it would take longer after hatching before it could fly. A modern precocial bird takes for 3–6 weeks from hatching to flying. In Archaeopteryx this milestone might have taken about 18 weeks. It might have taken two to three years to reach its final adult size. The evolution of the physiology of modern forms occurred later in the group's history. They have had over 140 million years to evolve after Archaeopteryx. This is an example of mosaic evolution, where some characters in a transitional form are basal, while others are remarkably advanced.

Chinese bird fossils

Jurassic fossils
Anchiornis huxlei is so far the only dinobird fossil known which lived before Archaeopteryx. It was found in Liaoning, China. The strata dates to the mid-late Jurassic period, 160 to 155 million years ago. There are also feather-bearing non-flying dinosaurs from the Jurassic of China, such as the maniraptoran Epidexipteryx. Epidexipteryx is the earliest known example of ornamental feathers in the fossil record, about 152 to 168 million years ago.

Anchiornis had large wings, made up of flight feathers attached to the arm and hand (as in modern birds) as well as flight feathers on the hind legs, forming an arrangement of fore and hind wings. The forewing of Anchiornis was composed of 11 primary feathers and 10 secondary feathers. The primary feathers in Anchiornis indicated poorer aerodynamic ability compared to its later relatives. In Microraptor and Archaeopteryx, the longest forewing feathers were closest to the tip of the wing, making the wings appear long, narrow, and pointed. However, in Anchiornis, the longest wing feathers anchored near the wrist, making the wing broadest in the middle and tapering near the tip for a more rounded, less flight-adapted profile.

So the animal could glide, but probably not fly.

Cretaceous fossils

Flying gave the birds access to many new habitats, and an adaptive radiation took place. We see the results of this rapid evolution in the Chinese fossils from the Lower Cretaceous, which are more varied, and mostly more advanced, than Archaeopteryx. There are now 31 different bird genera from the Lower Cretaceous of China. It is also clear, from the tail feathers of Confuciusornis (one of the Chinese fossils), that some of these birds were already using feathers for signalling and display, just as they do today. Like heat regulation, using feathers for display may be much earlier than flight. Confuciusornis is the fifth oldest bird fossil, about 25 million years after Archaeopteryx.
Most dinosaurs died out in the K/T extinction event, at the end of the Cretaceous. The only ones that survived were the birds. The birds, therefore, are not just the descendents of reptiles, but the descendents of theropod dinosaurs. Birds are the last surviving dinosaurs.

Colour of feathers
The pigments preserved in a 120 million year old fossil bird have been revealed using X-rays. A team scanned the beautifully preserved fossils of Gansus yumenensis and Confuciusornis sanctus. Their study, published in the journal Science, revealed the chemical fingerprint of pigments that once tinted the ancient bird's feathers. The trace metal copper is a marker for the dark pigment eumelanin. "The X-ray technique was so sensitive that it was able to show that each molecule of copper it detected was being tugged and squashed into a particular shape because it was bound within a eumelanin molecule".

Research of this kind has now been repeated several times.

Dinobirds
This is an informal grouping of theropods closest related to birds. These groups are small dinosaurs. They definitely have pennaceous feathers (like birds), and therefore probably temperature regulation. One proposed classification is:
 Eumaniraptora or Paraves
 Deinonychosauria
 Troodontidae
 Dromaeosauridae
 Aves

The earliest example of a dinobird is a troodont, Anchiornis huxlei, from the Upper Jurassic. This specimen pre-dates Archaeopteryx by 5–10 million years, and predates any other feathered dinosaur from its location (Liaoning Province, China) by 25–35 million years. This species had long feathers on its hind limbs as well as fore limbs, and could glide, but probably not fly.

At least this clade of theropods had well-developed genuine feathers before the first known bird. Feathering in other groups of theropods is still uncertain. One compsognathid, Sinosauropteryx, has plumaceous feathers, as does Shuvuuia, another small theropod. Apparently, many small theropods carried feathers, whose function was thermoregulation (to keep warm).

If we look just before the extinction event. there are examples of birds which are even more like modern birds, such as Asteriornis.

Extinction event
There is now evidence that many early bird groups went extinct at the end of the Cretaceous period (K/T extinction event). This is the same time that the other dinosaurs went extinct.

"Analysing 24 specimens, the researchers identified 17 species, seven of which were 'archaic birds' that are not seen after the K-T mass extinction. These findings show for the first time a diversity of archaic birds alive, right up until the end of the Cretaceous. This would mean that the archaic birds went extinct abruptly 65 million years ago, and that modern birds must have descended from just a few groups that survived the event".

Researchers dated the fossils to within 300,000 years of the boundary layer at the end of the Cretaceous.

A May 2018 report, in Current Biology, says that its authors think that the birds that survived the end-of-Cretaceous disaster were Neornithes, Neognathae (Galloanserae + Neoaves). They were not tree-living, and could not fly far. After the world-wide destruction of forests, it took a long time for the world's forests to return properly. Virtually the same conclusions were already reached before, in a 2017 book on avian evolution.

Origin of modern birds
All living birds are Neornithes, a subclass in traditional taxonomy. The Ornithurae is the natural group made up of modern birds and their extinct relatives. Their relatives include Ichthyornis and Hesperornis, and some of the Chinese Cretaceous birds. They all have a plough-shaped pygostyle, a bone at the end of the tail which allows the tail feathers to fan and retract. Other groups of birds became extinct in the K/T extinction event.

Gansus is a genus of aquatic birds that lived during the Lower Cretaceous, somewhere between 115 and 105 million years ago in what is now Gansu province, western China. It may be the oldest-known of the Ornithurae, depending how that group is defined.

Under any definition, all living birds, including taxa as diverse as ostriches, hummingbirds and eagles, are descended from basal ornithurans, many of which were semi-aquatic. It is now thought possible that all modern birds descended specifically from a semi-aquatic bird similar to Gansus. Thus, while Gansus is not necessarily a direct ancestor of today's birds, it is closely related to such an ancestral species.

Related pages
 Lagerstätte
 Jehol biota
 Bird

References

Coelurosaurs
Birds
Evolutionary biology
Fossils

Origin of birds


Johann Sebastian Bach (21 Machi 1685 hadi 28 Julai 1750) alikuwa mtungaji wa muziki na mpiga piano na kinanda cha filimbi kutoka nchi ya Ujerumani. Alitunga muziki za aina zote, iliyotumika kidini na kidunia. Alitunga muziki kwa kwaya, chombo kimoja cha muziki, na kundi la wanamuziki (okestra). Ingawa hakuunda mifumo mipya ya muziki, alitajirisha mitindo ya muziki kule Ujerumani; tena alitohoa mitindo ya muziki ya Kiitalia na ya Kifaransa.

Marejeo

Utaalamu wa kisasa
 Butt J (ed), The Cambridge companion to Bach, Cambridge, Cambridge University Press, 1997 (ISBN 0-521-58780-8)
 A collection of writings on the historical context (society, beliefs and world view), profiles of his music, and influence and reception.
 David HT, Mendel A (eds), revised and expanded by C Wolff, The new Bach reader, 2nd ed, New York, Norton, 1999 (ISBN 0-393-31956-3)
 A significant repository of documentary evidence, including contemporary documents, some by Bach himself. This book includes an English translation of the biography of Bach, by the early 19th-century German musicologist Forkel.
 Wolff C, Johann Sebastian Bach: the learned musician, New York, Norton, 2001 (ISBN 0-393-32256-4)
 A comprehensive and engaging account of Bach's life.
 Williams P, The life of Bach, Cambridge, Cambridge University Press, 2004 (ISBN 0-521-53374-0)
 A shorter expose of the composer's life, using his obituary as the starting point; a valuable complement to Wolff's biography.
 Stauffer G, J. S. Bach as organist: his instruments, music, and performance practices, Indiana University Press, 1999 (ISBN 0-253-21386-X) (paperback reprint of hardcover, 1986, ISBN 0-253-33181-1)
 Boyd, Malcolm. Bach, Oxford University Press; 3rd ed. (2000) ISBN 0-19-514222-5

Utaalamu wa zamani
 Schweitzer A, J. S. Bach, 2 vol, Dover, 1966, translated by Ernest Newman (ISBN 0-486-21631-4) (reprint of New York, Macmillan, 1955-1958)
 Spitta P, Johann Sebastian Bach, his work and influence on the music of Germany, 1685-1750, London, Novello, 1884-85
 An early, groundbreaking, three-volume study of Bach's life and music.
 Forkel, Johann Nicolaus; On Johann Sebastian Bach's Life, Genius, and Works, (1802), translated by A. C. F. Kollmann (1820)

Masomo mengine
 Rasmussen, Michelle (Agosti 2001) "Bach, Mozart, and the 'Musical Midwife'", The New Federalist
 Hofstadter D, Gödel, Escher, Bach: an eternal golden braid
Explores cognition, formal methods, logic and mathematics—particularly Gödel's incompleteness theorem—in the music of Bach, the art of MC Escher and other sources.

Marejeo ya nje

Marejeo ya jumla
 Bach-Leipzig.de , Bach-Archiv Leipzig
 JSBach.org, by Jan Hanford - extensive information on Bach and his works; huge and growing database of user-contributed recordings and reviews
 J.S. Bach FAQ (from the Internet Archive), by Bernard Greenberg - answers many common questions about Bach
 JSBach.net, maintained by David J. Grossman - includes a catalog of works, images, MIDI files, and audio
 J.S. Bach on Radio 3 - extensive resources on Bach, on occasion of BBC Radio 3's complete airing of Bach's works in Dec 2005
 J.S. Bach bibliography , by Yo Tomita of Queen's Belfast - especially useful to scholars
 Bach-Cantatas.com, by Aryeh Oron - information on the cantatas as well as other works
 Canons and Fugues , by Timothy A. Smith - various information on these contrapuntal works
 Carolina Classical: J.S. Bach  - detailed biography with PDF scores of selected cantatas
 1911 Encyclopaedia Britannica entry on J.S. Bach, provided by Jim McKeeth

Maandishi ya muziki
 IMSLP's ongoing project to sort and make freely avalible all of Bach's works from the Bach Gesellschaft Ausgabe.
 Piano Sheet Music of Bach  including Fugues, Preludes, and more in PDF.
 Arrangements of music by Bach for guitar

Kurekodiwa kwa muziki
 james kibbie - bach organ works, Free downloads of the complete organ works of Johann Sebastian Bach, recorded by Dr. James Kibbie on original baroque organs in Germany
 Piano Society: J.S. Bach - A biography and various free recordings in MP3 format.
 Bach cylinder recordings , from the Cylinder Preservation and Digitization Project at the University of California, Santa Barbara Library.
 Skwik.com downloads - Toccata and Fugue in D minor and more
 Music for piano (midi)

Mada maalumu
 Bach manuscripts  - video lectures by Christoph Wolff on the Bach family's hidden manuscripts archive
 Faces of Bach  - Site discussing the portraits of J.S.Bach.
 Bach Tuning
 An article on Bach's tuning script from his manuscript of The Well Tempered Clavier
 J.S. Bach's work in films

Makundi ya wanamuziki wanaocheza muziki ya Bach
 Bach Collegium - Fort Wayne Utlizing early instruments and techniques
 Washington Bach Consort
 The American Bach Society
 The Bach Choir of Bethlehem
 Oregon Bach Festival
 Mathayo Passion

Waliozaliwa 1685
Waliofariki 1750
Watunzi
Wanamuziki wa Ujerumani

Johann Sebastian Bach


Blackheath is a town in the Sandwell Metropolitan Borough, in the county of West Midlands, England.

History
Before 1841, Bleak Heath or Blake Heath was a small group of farm houses and inns on the turnpike road from Oldbury to Halesowen, within Rowley Regis. The changes brought about by the industrial revolution led to a Private Act in June that year that allowed the sale of the Rowley Regis glebe lands in order to finance the building of a new vicarage.

The land was purchased by developers who, throughout the remainder of the 19th century, expanded Blackheath as a dormitory town for the surrounding industries, in particular, the coal mine at Coombes Wood and the Hailstone quarry. Workers migrated to Blackheath from across England and particularly from Wales until the town and its neighbours grew to form the existing conurbation with nearby Birmingham.

Churches
The parish of St Paul was established in 1865 as a distinct entity from that of Rowley Regis and the new church consecrated in 1869. There has also been a long tradition of nonconformism with many Methodist and Baptist chapels.

Manufacturing, railways, and industrialisation
A market was established and an extension of the Great Western Railway linking Birmingham and Worcester opened a  in the town in 1867.

Into the 20th century, manufacturing grew and extractive industries declined with the last coal mine closing in 1919. Major employers were the fasteners business at the Excelsior Works of Thomas William Lench and the electrical engineering business of British Thomson-Houston (BTH). Manufacturing remained the main source of income up to the start of the 21st century with the BTH works still in operation though in the intervening years it has worked under the successive names of AEI, GEC, GEC-ALSTHOM, Hawker Siddeley, BTR and Electrodrives.

Borough and county membership
Blackheath was part of the borough of Rowley Regis until 1966, when it became part of the county borough of Warley. Since 1974 it has formed part of the metropolitan borough of Sandwell.

It was historically part of Staffordshire until 1966, when the boundaries were altered to incorporate the new borough of Warley into Worcestershire. Since 1974, it has been part of the West Midlands metropolitan county.

Economy
Blackheath has always been a predominantly working class area dominated by modest housing. The town was hard hit by the economic slow-down of the 1970s and unemployment of the early 1980s. However, in the 1990s the town became more prosperous with improving housing stock and some substantial development in town centre stores and improvement in the road network. A J Sainsbury supermarket opened in the town centre around this time.

Blackheath has many transport links with buses travelling throughout the borough and Rowley Regis railway station is nearby.

Other information
Blackheath Primary School is located in the area, and was originally built by Rowley Regis urban district council on Powke Lane during the late 19th century, incorporating a 5-7 infant school and 7-11 junior school and later including a nursery unit for 3 and 4 year olds. The schools merged in September 1990 to form Blackheath Primary School. It relocated to a site on Britannia Road, previously occupied by Britannia High School, in September 2005.

Football team Blackheath Town F.C. played in the West Midlands (Regional) League Division One (South) but are now just a youth development squad.

On 6 April 1959, the town was the scene of the first major racially motivated incident in the West Midlands when some 30 Teddy Boys clashed with a group of black people.

With rising traffic on local roads after the Second World War, Blackheath became a congestion hotspot. Things improved slightly with the construction of a new road around the north of the town centre towards the end of the 1970s, but this was only of use to traffic coming to and from Cradley Heath and Brierley Hill. Motorists travelling from Quinton still had to negotiate the original route that was little better than it had been in the days before cars. This problem was solved in 2006 with a new relief road that circles the eastern half of the town centre and diverts traffic coming from Halesowen, Quinton and Oldbury.

Blackheath has some of the strongest public transport links in the Black Country. It has direct bus and rail links with Birmingham, while the extensive bus network gives locals a direct route to Oldbury, Halesowen, Dudley, Cradley Heath, West Bromwich, Wolverhampton, Merry Hill Shopping Centre and Walsall.

Notable people
Tommy Smart, professional footballer for England and Aston Villa
Glenn Tipton, guitarist with Judas Priest was born in Blackheath in 1947
Samuel Page (fl. 1925), professional football goalkeeper
Debbie McGee, magician's assistant, visited Blackheath in 1984.

Notes

References

Towns in the West Midlands (county)
Areas of Sandwell
Rowley Regis

Blackheath, West Midlands


Invincible is a 2006 American biographical sports drama film directed by Ericson Core. It is based on the nonfictional story of Vince Papale (Mark Wahlberg), who played for the Philadelphia Eagles from 1976 to 1978 with the help of his coach, Dick Vermeil (Greg Kinnear). The film was released in the United States on August 25, 2006.

Plot

In the 1970s, Philadelphia is in chaos as southern portions of the city protest the shutdown of several job sites while their NFL team, the Philadelphia Eagles, endures a string of losing seasons. In 1976, a 30 year old substitute teacher Vince Papale goes to a sandlot one night and joins his friends playing a pick-up football game against another group of young men. After the game ends, Papale goes home and finds his wife Sharon disgusted with his failure to provide proper support.

The next morning, Papale is unexpectedly laid off from his job at the school. That night, Papale goes to the bar where he works as a part-time bartender. The bar contains die-hard Eagles fans, who are watching a TV report on Eagles hiring a new head coach, Dick Vermeil, who will be staging open public tryouts for the Eagles; the bar regulars encourage Papale to attend the tryout. Returning home, Papale finds out that Sharon has left him, leaving him a note saying he will never be anything in the world. Distraught, Papale trashes the few remaining belongings that she left behind.

The next night at the bar, Papale meets a new co-bartender, Janet Cantrell, who is a Giants fan. Desperate for income in the aftermath of his wife's departure, Papale receives support from his friends and attends the tryout hosted at Veterans Stadium. Papale is competing against several hundred Philadelphia residents, but performs well during the workouts. After the tryouts, Dick Vermeil comes by as Papale is trying to start his car. Vermeil is impressed by Papale's performance and invites him to training camp to compete for a roster spot with the Eagles. Accepting, Papale receives a warm welcome at the bar, and has an interview with a newscaster.

The next day, Papale is jogging in the city and stops by his empty home; running into friends, he tells them about joining the Eagles. His father, meanwhile, offers to let Vince stay with him. The following day, he goes to his first training camp with the Eagles. As the days of training camp progress, Papale endures hard training and disrespect from other players. One night, Papale takes Janet out on a date. He is unsure if he can start a new relationship, since he needs to try his best to make the team. Janet claims that she did not know it was a date. She goes back to work and he leaves. As training camp ends, the final roster spot is down to Papale and a veteran. Against his assistants' advice, Vermeil hands the final spot to Papale.

As Papale's career with the Eagles begins, the team loses all six preseason games and their regular season opener against the Dallas Cowboys. Papale plays poorly against the Cowboys, and Vermeil faces pressure from the fans and media. After the team returns to Philadelphia, Papale goes to the sandlot where he played with his friends once before. He is invited to play, but he declines because of his upcoming Eagles game and watches for a few minutes. However, as a rainstorm begins, Papale joins his pals and plays against another sandlot team to help his friends. He ends the wet and dirty game by throwing a touchdown pass. When he runs into Janet later, they speak briefly before passionately embracing and tumbling into Papale's home.

During the home opener against the New York Giants, Janet's appearance in a Giants shirt angers the Eagles fans. In the locker room, Papale looks again at the note Sharon had left and tears it up. He opens the game by solo-tackling the kickoff returner inside the fifteen-yard line. After an up-and-down game, Papale gets downfield during an Eagles' fourth quarter punt to tackle the returner, forcing a fumble that he recovers and takes into the end zone for a touchdown, giving the Eagles their first win in Papale's career. Eagles fans go wild with joy. During the end credits, media highlights of Papale's career with the Eagles are shown. Papale plays for the team for three seasons and eventually marries Janet while Vermeil succeeds in turning the Eagles into a winning team, culminating in an appearance in Super Bowl XV.

Cast

Differences from the true story
In reality, Papale started playing football in the Delaware County Rough Touch League (PA) in the late 60's before his semi-professional and pro football experience. He then played with the semi-pro Aston Green Knights of the Seaboard Football League and two seasons with the Philadelphia Bell of the World Football League, one of the NFL's rival leagues on the level of the AFL and the USFL. Papale was a standout special teams star for the Bell, who played at Philadelphia's JFK Stadium.

Mark Wahlberg was shorter (5'8") than Vince Papale, who stood at 6'2" while playing for the Eagles. Mark Wahlberg was closer to Vince Papale's high-school height of 5'7".

Vince Papale's first wife did leave him, leaving a similar note. However, that happened in 1971, five years before the events of the movie.

The movie portrays Vince meeting Janet before the tryouts. In real life, Papale dated and married his second wife, Sandy during the movie's time frame. He was divorced and met Janet after his Eagles career as the couple married in 1993.

Papale did participate in an open tryout before earning his spot on the Bell roster, which the filmmakers used as a model for the tryout shown in the movie. For the Eagles, Papale actually participated in a private workout that was by invitation only.

The opening scene of the movie features the Eagles' 31−0 loss to the Cincinnati Bengals on December 7, 1975. One of the fans makes a comment that the Eagles lost to a team worse than they were. In 1975, the Bengals actually went 11–3 and were the wild card team in the AFC.

The game versus the New York Giants is depicted as being a close defensive struggle, with the Giants scoring first to take a 7–0 lead. The Eagles actually won easily, 20–7, with the Giants not scoring until late in the game. The fumble recovery depicted in the climactic scene did occur, but Papale's touchdown did not count, under NFL rules at the time, since the ball could not be advanced. It was still a key play in the victory for the Eagles. Papale never scored a regular-season touchdown in the NFL. His only offensive stat came in the 1977 season, where he had 1 catch for 15 yards. However, he scored his first NFL touchdown against the Patriots in a 1977 exhibition game. As with so many of his breaks, this was a big one—the game-winning score. Rookie Quarterback Mike Cordova threw from the Pats' 14, and Cornerback Raymond Clayborn deflected the ball slightly allowing Papale to make a diving catch in the end zone.

Filming

The preseason/tryout scenes were filmed at Franklin Field at the University of Pennsylvania, and the Central High School Lancers field during July and August 2005. (For 13 seasons, 1958–1970, Franklin Field was the home field of the Eagles.) The crew used their locker room and field. The Lancers, who had a preseason, used Fairmount Park in West Philadelphia during this time. The office scenes were filmed in Delaplaine McDaniel Middle School, during renovations to the school at 1801 Moore Street South Philadelphia. The carnival scenes were filmed at Our Lady of Mount Carmel School in South Philadelphia at 2329 South Third Street. Some of the street scenes were filmed on location in the city. The remainder of the film was filmed in a former aircraft carrier parts warehouse on Langley Avenue in the Philadelphia Naval Business Center. The crew shared this facility with the floats for the Philadelphia Thanksgiving Day Parade. The film opens with Jim Croce's "I Got a Name".

Box office
In opening weekend the movie made approximately $17,031,122 domestically. The movie generated an estimated $57,806,952 domestically.

Reception
The film received generally positive reviews from critics. It is certified "fresh" with a 72% approval rating on Rotten Tomatoes and has an average rating of 6.46/10, based on 135 reviews. The website's critical consensus reads, "As simple and authentic as the gritty South Philly environs in which it's set in, Invincible sends a uplifting and heartfelt message packed with an athletic enthusiasm that shouldn't be missed". On Metacritic, the film reached a score of 63 based on 28 critics, indicating "generally favorable reviews". Common Sense Media gave the film 4 out of 5 stars. Audiences polled by CinemaScore gave the film an average grade of "A-" on an A+ to F scale.

In popular culture
The film also inspired the show It's Always Sunny in Philadelphia in its third season in an episode called "The Gang Gets Invincible" in which Dennis, Mac and Dee try out for the Philadelphia Eagles due to the movie Invincible; they also repeatedly refer to it as "that New Kids on the Block movie", seemingly confusing lead Mark Wahlberg, and specifically his lead role with Marky Mark and the Funky Bunch, with his brother Donnie Wahlberg.

Home media
The film released on DVD and Blu-ray on December 19, 2006. It re-released on a two-disc Blu-ray set on March 29, 2011.

See also

The Garbage Picking Field Goal Kicking Philadelphia Phenomenon
 List of American football films

References

External links

 Invincible at the Sports Movie Database

2006 films
2000s sports drama films
American football films
2006 directorial debut films
Films set in Philadelphia
Films shot in Philadelphia
Films set in the 1970s
Films set in 1976
Philadelphia Eagles
Sports films based on actual events
Walt Disney Pictures films
Films scored by Mark Isham
Biographical films about sportspeople
Biographical films about educators
Cultural depictions of players of American football
Films directed by Ericson Core
2006 drama films
2000s English-language films
2000s American films

Invincible (2006 film)


Chaparral is a shrubland or heathland plant community. It is found mainly in the U.S. state of California. Also in the northern portion of the Baja California peninsula, Mexico. It is caused by a Mediterranean climate (mild, wet winters and hot dry summers) and wildfire.

A chaparral has summer drought-tolerant plants. They have hard sclerophyllous evergreen leaves. Chaparral covers 5% of the state of California. Of the associated Mediterranean shrubland, it covers an additional 3.5%. The name comes from the Spanish word chaparro, referring to scrub oaks.

There are four other chaparral regions in the world.
parts of the Mediterranean coast, known as maquis
Central Chile, known as matorral
South African Cape, known as fynbos
South Australia, known as kwongan

Chaparral does not often have fires. These are usually at intervals from 10–15 years to over a hundred years. Mature chaparral often has dense thickets. They are highly flammable.

References

Ecoregions

Chaparral


Full employment is an idea from economics. It means that every person that is able and willing to work can get a job. It does not mean that all people have a job: People who do not have the skills the employers want may still not have a job, because there simply is no role that fits them. This is called structural unemployment. Also, it is very likely that there will be people looking for jobs (called frictional unemployment).

In general, people say there is full employment, if the percentage of people who are able and willing to work, but who do not have a job is below a given rate. In 1945, William Henry Beveridge said there was full employment if there are more jobs than job seekers. He said that an unemployment rate of three percent of frictional (short term) unemployment can be considered full employment.

Related pages
Job guarantee

Employment

Full employment


Samuel Merwin, Sr. (6 October 1874 – 17 October 1936) was an American playwright and author.

Biography
Merwin was born on 6 October 1874 in  Evanston, Illinois to Ella B. and Orlando H. Merwin. His father was the postmaster of Evanston. In 1901, Merwin married Edna Earl Fleshiem. The couple had two sons, Samuel Kimball Merwin, Jr. and Banister Merwin and one adopted son, John Merwin.

After attending Northwestern University, he worked between 1905 and 1911 as associate editor and then editor of Success magazine. In 1907 the magazine sent him to China to investigate the opium trade.

He died of a stroke while dining at The Player's Club in Manhattan on 17 October 1936.

Publications

The Short Line War (1899) with Henry Kitchell Webster
Calumet "K" (1901) with Henry Kitchell Webster
The Road to Frontenac:  A Romance of Early Canada (1901)
The Whip Hand (1903)
His Little World: The Story of Hunch Badeau (1903)
The Merry Anne (1904)
The Road Builders (1905)
Comrade John (1907) with Henry Kitchell Webster
Drugging a Nation. (1908)
The Citadel:  A Romance of Unrest (1912)
Anthony the Absolute (1914)
The Charmed Life of Miss Austin (1914)
The Honey Bee:  A Story of a Woman in Revolt (1915)
The Trufflers (1916)
Temperamental Henry:  An Episodic History of the Early Life and the Young Loves of Henry Calverly, 3rd (1917)
Henry Is Twenty:  A Further Episodic History of Henry Calverly, 3rd (1918)
The Passionate Pilgrim:  Being the Narrative of an Oddly Dramatic Year in the Life of Henry Calverly, 3rd (1919)
Hills of Han: A Romantic Incident (1919)
In Red and Gold (1921)
Goldie Green (1922)
Hattie of Hollywood (serialized in Photoplay, July–December 1922)
Silk : A Legend as Narrated in the Journals and Correspondence of Jan Po (1923)
The Moment of Beauty (1925)
The Entertaining Angel (1926)
"Old Concord, Seen through Western Spectacles" (1926)
Anabel at Sea (1927)
Lady Can Do (1929)
Bad Penny (1933)
Rise and Fight Againe:  The Story of a Life-Long Friend (1935)

References

External links

1874 births
1936 deaths
19th-century American novelists
20th-century American novelists
American male novelists
19th-century American male writers
20th-century American male writers

Samuel Merwin (writer)


Bilahari is a rāgam in Carnatic music (musical scale of South Indian classical music). It is a janya rāgam (derived scale) from the 29th melakarta scale Sankarabharanam. It is a janya scale, as it does not have all the seven swaras (musical notes) in the ascending scale. It is a combination of the pentatonic scale Mohanam and the sampurna raga scale Sankarabharanam.

Structure and Lakshana

Bilahari is an asymmetric rāgam that does not contain madhyamam or nishādham in the ascending scale. It is an audava-sampurna rāgam (or owdava rāgam, meaning pentatonic ascending scale). Its  structure (ascending and descending scale) is as follows:

 :  they are used in every song

 :

The notes used in this scale are shadjam, chathusruthi rishabham, antara gandhara, panchamam and chathusruthi dhaivatham in ascending scale, with kakali nishadham and shuddha madhyamam included in descending scale. For the details of the notations and terms, see swaras in Carnatic music.

This rāgam also uses kaishiki nishadham (N2) as an external note (anya swara) in the descending scale. Hence it is considered a bhashanga rāgam, a scale with notes external to the parent scale.

Popular compositions
There are many compositions set to Bilahari rāgam. Here are some popular kritis composed in Bilahari.

Sharanu Janakana By Purandara Dasa
Belagu Javadi Baro By Vadiraja Tirtha
Lakshmi Shobhane By Vadiraja Tirtha. This is one of the greatest literary works of Vadiraja Tirtha with 112 Charanas and the longest composition known by a carnatic composer
Hanumana Maneyavaru by Vidyaprasanna teertha in Kannada
Na jeevadhara, Dorakuna ituvanti and Kanukontini composed by Tyagaraja
Sri Balasubramanya, Kamakshi Sri Varalakshmi by Muthuswami Dikshitar
Smara Sada, Aaradhayami, Gopalam Seveham, Pahi Padmanabha, Jaya Suganalaya, Pahi Sarasanabha, Santhatham Bhajami and Vimukhava Tava by Maharaja Swathi Thirunal Rama Varma
Parithana michite by Patnam Subramania Iyer
Sri Chamundeshwari by Mysore Vasudevacharya
Anaamilo mahaboob is a Khayal in Hindi by Maharaja Swathi Thirunal Rama Varma
 Puraya Mama Kamam  is a Tharangam by Narayana Teertha
 "Raa ra venu gopala" a famous Swarajathi was composed in Bilahari
Rabindranath Tagore has composed 'Ami Marer Sagor Pari Debo' In Raga Bilahari.
" Intha Chouka" is a varnam composed by Veenai Kuppaiyer
Maa Mayura a Tamil Kriti composed by Mazhavai Chidambara Bharathi

Film songs

Language:Tamil

Related rāgams
This section covers the theoretical and scientific aspect of this rāgam.

Scale similarities
Mohanam has a symmetric pentatonic scale, with the notes same as the ascending scale of Bilahari. Its  structure is S R2 G3 P D2 S : S D2 P G3 R2 S
Mohanakalyani is a rāgam which has the prati madhyamam in descending scale (descending scale of Kalyani) in place of the shuddha madhyamam. Its  structure is S R2 G3 P D2 S : S N3 D2 P M2 G3 R2 S
Garudadhvani is a rāgam which has the ascending and descending scales interchanged, in comparison with Bilahari. Its  structure is S R2 G3 M1 P D2 N3 S : S D2 P G3 R2 S
Desakshi is a raga which is similar to Bilahari. The arohana remains the same, while the sampoorna avarohana has Kaishiki Nishada in place of Kakali Nishada.

Notes

References

Janya ragas

Bilahari


The Oregon Trail is a text-based strategy video game developed by Don Rawitsch, Bill Heinemann, and Paul Dillenberger in 1971 and produced by the Minnesota Educational Computing Consortium (MECC) beginning in 1975. It was developed as a computer game to teach school children about the realities of 19th-century pioneer life on the Oregon Trail. In the game, the player assumes the role of a wagon leader guiding a party of settlers from Independence, Missouri, to Oregon City, Oregon via a covered wagon in 1847. Along the way the player must purchase supplies, hunt for food, and make choices on how to proceed along the trail while encountering random events such as storms and wagon breakdowns. The original versions of the game contain no graphics, as they were developed for computers that used teleprinters instead of computer monitors. A later Apple II port added a graphical shooting minigame.

The first version of the game was developed over the course of two weeks for use by Rawitsch in a history unit at Jordan Junior High School in Minneapolis. Despite its popularity with the students, it was deleted from the school district's mainframe computer at the end of the school semester. Rawitsch recreated the game in 1974 for the MECC, which distributed educational software for free in Minnesota and for sale elsewhere, and recalibrated the probabilities of events based on historical journals and diaries for the game's release the following year. After the rise of microcomputers in the 1970s, the MECC released several versions of the game over the next decade for the Apple II, Atari 8-bit family, and Commodore 64 computers, before redesigning it as a graphical commercial game for the Apple II under the same name in 1985.

The game is the first entry in The Oregon Trail series; games in the series have since been released in many editions by various developers and publishers, many titled The Oregon Trail. The multiple games in the series are often considered to be iterations on the same title, and have collectively sold over 65 million copies and have been inducted into the World Video Game Hall of Fame. The series has also inspired a number of spinoffs such as The Yukon Trail and The Amazon Trail.

Gameplay

The Oregon Trail is a text-based strategy video game in which the player, as the leader of a wagon train, controls a group journeying down the Oregon Trail from Independence, Missouri to Oregon City, Oregon in 1847. The player purchases supplies, then plays through approximately twelve rounds of decision making, each representing two weeks on the trail. Each round begins with the player being told their current distance along the trail and the date, along with their current supplies. Supplies consist of food, bullets, clothing, miscellaneous supplies, and cash, each given as a number. Players are given the option to hunt for food, and in some rounds to stop at a fort to purchase supplies, and then choose how much food to consume that round. The game closes the round by randomly selecting one or two events and weather conditions. The events include storms damaging supplies, wagons breaking down, and attacks by wild animals or "hostile riders"; weather conditions can slow down the rate of travel, which can result in additional rounds needed to reach Oregon.

When hunting, or when attacked, the game prompts the player to type a word—"BANG" in the original version, or a randomly selected word like "BANG" or "POW" in later versions—with misspellings resulting in no effect. When hunting, the faster the word is typed, the more food is gathered. The game ends when the player reaches Oregon, or if they die along the trail; death can occur due to an attack or by running out of supplies. Running out of food results in starvation, while lack of clothing in cold weather, low levels of food, or random events such as snakebite or a hunting accident lead to illness; this results in death if the player does not have miscellaneous supplies for minor or regular illnesses, or cannot afford a doctor in the case of serious illnesses.

Development

Original version

In 1971, Don Rawitsch, a history major and senior at Carleton College in Northfield, Minnesota, taught an 8th-grade history class at Jordan Junior High School in Minneapolis as a student teacher. His supervising teacher assigned him to prepare a unit on "The Western Expansion of the Mid-19th Century", and Rawitsch decided to create a board game activity about the Oregon Trail for the students. After one week of planning the lessons, he was in the process of drawing out the trail on sheets of paper on the floor of his apartment when his roommates, fellow Carleton students Bill Heinemann and Paul Dillenberger, came in. Heinemann, who along with Dillenberger was a math student and student teacher with experience in programming, discussed the project with Rawitsch, and told him that it would be well-suited to a computer program, as it could keep track of the player's progress and calculate their chances of success based on their supplies instead of a dice roll. Rawitsch was initially hesitant, as the unit needed to be complete within two weeks, but Heinemann and Dillenberger felt it could be done if they worked long hours each day on it. The trio then spent the weekend designing and coding the game on paper.

The Minneapolis school district had recently purchased an HP 2100 minicomputer, and the schools the trio were teaching in, like the other schools in the district, were connected to it via a single teleprinter. These teleprinters could send and print messages from programs running on the central computer. The video game industry was in its infancy in 1971, and the three had no resources to draw on to develop the game software beyond their own programming knowledge; instead, they spent two weeks working and coding in HP Time-Shared BASIC on their own. Rawitsch focused on the design and historical portions of the game, while Heinemann and Dillenberger did the programming, working on the teleprinter kept in a small room that was formerly a janitor's closet at the school they taught at, Bryant Junior High School, as well as bringing it to the apartment to continue working. Heinemann focused on the overall programming flow, and came up with the hunting minigame, while Dillenberger made subroutines for the game to use, wrote much of the text displayed to the player, and tested for bugs in the code. As there was only one terminal, Heinemann wrote code on paper while Dillenberger entered it into the system along with his own.

They implemented the basics of the game in those two weeks, including purchasing supplies, making choices at specific points of the journey, and the hunting minigame. They also included the random events happening to the player, and Heinemann had the idea to make the random events tied to the geography of the trail, so that cold weather events would be more likely in the mountains and attacks more likely in the plains. They also added small randomization of outcomes such as the amount of food gained from hunting; they expected that in order for the children to be interested in playing the game multiple times there needed to be variations between plays. Prior to the start of Rawitsch's history unit, Heinemann and Dillenberger let some students at their school play it to test; the students were enthusiastic about the game, staying late at school to play. The other teachers were not as interested, but did recommend changes to the game, particularly removing negative depictions of Native Americans as they were based more on Western movies and television than history, and could be problematic towards the several students with Native American ancestry at the schools.

The Oregon Trail debuted to Rawitsch's classes on December 3, 1971. He was unsure how interested the students would be in the game, as they had had limited exposure to computers and several seemed uninterested in history altogether, but after he showed them the game students would line up outside the door for their turn and stay after school for another chance. Rawitsch has recounted that, as only one student could use the teleprinter at one time and he could only reserve it for one week, he had the students play in groups, and they organized themselves into voting for responses and delegating students to handle hunting, following the map, and keeping track of supplies. Other teachers at the school came up with "flimsy excuses" for their students to try the game as well. The trio adjusted the game's code as the students played in response to bugs found, such as purchasing clothes for negative money. As the school district shared a single central minicomputer, schools across the city began to play the game as well. When the semester and their student teaching term ended, the team printed out copies of the source code—about 800 lines of code—and deleted the program from the computer.

MECC version
In 1974, Rawitsch was hired by the Minnesota Educational Computing Consortium (MECC), a state-funded organization that developed educational software for the classroom, as an entry-level liaison for local community colleges. The MECC had a similar system to the Minneapolis school district's setup in 1971, with a CDC Cyber 70/73-26 mainframe computer which schools across the state could connect to via terminals. The system contained several educational programs, and Rawitsch's boss let him know that it was open to submissions. Rawitsch, with permission from Heinemann and Dillenberger, spent the 1974 Thanksgiving weekend copying and adjusting the printed BASIC source code into the system. Rather than submit the recreated copy, he instead enhanced the game with research on the events of the Oregon Trail that he had not had time for with the original version, and changed the frequency and types of random events, such as bad weather or wagons breaking down, to be based on the actual historical probabilities for what happened to travelers on the trail at each location in the game. Rawitsch calculated the probabilities himself, basing them on historical diaries and narratives of people on the trail that he read. He also added in more positive depictions of Native Americans, as his research indicated that many settlers received assistance from them along the trail. He placed The Oregon Trail into the organization's time-sharing network in 1975, where it could be accessed by schools across Minnesota.

Legacy
The 1975 mainframe game was the most popular software in the system for Minnesota schools for five years, with thousands of players monthly. Rawitsch, Heinemann, and Dillenberger were not publicly acknowledged as the creators of the original game until 1995, when MECC honored them in a ceremony at the Mall of America. By then, several versions of the game had been created. Rawitsch published the source code of The Oregon Trail in Creative Computings May–June 1978 issue, along with some of the historical information he had used to refine the statistics. That year MECC began encouraging schools to adopt the Apple II microcomputer, purchasing large amounts at a discount and reselling them to schools. MECC began converting several of their products to run on microcomputers, and John Cook adapted the game for the Apple II; though the text-based gameplay remained largely the same, he added a display of the player's position along the trail on a map between rounds, and replaced the typing in the hunting and attack minigame with a graphical version in which a deer or attacker moves across the screen and the player presses a key to fire at it. A version for the Atari 8-bit family, again titled The Oregon Trail, was released in 1982. The Apple II version was included under the name Oregon as part of MECC's Elementary series, distributed to Minnesota schools for free and for profit to schools outside of the state, on Elementary Volume 6 in 1980. Oregon was ported to the Commodore 64 in 1984 as part of a collection like Elementary Volume 6 titled Expeditions. By the mid-1980s, MECC was selling their educational software to schools around the country, and The Oregon Trail was their most popular product by far.

In 1985, MECC produced a fully-graphical version of the game for Apple II computers, redesigned by R. Philip Bouchard as a greatly expanded product for home consumers under the same name. The Oregon Trail was extremely successful, and along with successive versions of the game it sold over 65 million copies. Several further games have been released in The Oregon Trail series, many under the title The Oregon Trail, as well as a number of spinoffs such as The Yukon Trail and The Amazon Trail.

The original Oregon Trail has been described in Serious Games and Edutainment Applications as "one of the most famous ancestors" of the serious game subgenre. The text-based and graphical versions of The Oregon Trail are often described as different iterations of the same game when discussing the game's legacy; Colin Campbell of Polygon, for example, has described it collectively as one of the most successful games of all time, calling it a cultural icon. Kevin Wong of Vice claimed that the collective game was "synonymous with edutainment". Due to its widespread popularity, The Oregon Trail, referring to all versions of the game released over 40 years, was inducted into the World Video Game Hall of Fame in 2016. Time named the game as one of the 100 greatest video games in 2012, and placed it 9th on its list of the 50 best games in 2016.

References

External links
 The 1975 version of The Oregon Trail can be played for free in the browser at the Internet Archive

The Oregon Trail (series)
1971 video games
1975 video games
Apple II games
Children's educational video games
Commercial video games with freely available source code
Classic Mac OS games
History educational video games
Mainframe games
Survival video games
Video games developed in the United States
Video games set in the 19th century
Video games with textual graphics
Western (genre) video games
World Video Game Hall of Fame
Video games set in the United States
Teleprinter video games

The Oregon Trail (1971 video game)


The Rookwood Cemetery Line used to be a part of the Sydney suburban network. The line serviced Rookwood Cemetery and was built in 1864, opening on 22 October 1864.<ref
name="list_of_openings">List of Opening Dates of N.S.W. Rail Lines Prior to June 1942: Compiled from listings in The Retired Rail and Tramwayman, 1942</ref>

History

With the closure of the Town Hall and Devonshire Cemeteries by the mid-19th century and an ever-increasing population, a decision was made to purchase a huge area of land (250 acres) in 1862 to establish the Necropolis at Haslem's Creek in 1867. The term "necropolis" comes from the Greek "nekropolis" or "city of the dead".

As this location was some distance from the centre of Sydney and from the main-line train station at Haslem's Creek, now Lidcombe station, it was considered necessary to establish a railway station at the centre of the cemetery. This line would run as a spur line from the existing station at Haslem's creek and allow easier movement into and out of the cemetery.  The railway line construction began in November 1864 and from 1 January 1865 trains began their run into the cemetery.  However, The Sydney Morning Herald advertised the first regular services from 1 April 1867. The times advertised were for services at 8.30am and 4.15pm. Later this was changed to 9.15am and 3pm. It stopped at prearranged stations on the journey from central Sydney in order to pick up mourners and coffins. Some stations, such as Newtown had special platform areas and buildings reserved for mourners and coffins.

At the time of its opening, the line went as far as Cemetery Station No. 1. On 26 May 1897, an extension of the line to Cemetery Station No. 3 was opened. The extension required the removal of a waiting room on the rear wall of the Cemetery Station No. 1, so the line could pass right through the building. A final extension, to Cemetery Station No. 4 opened on 19 June 1908. The line closed in 1948.

Closure

The last trains that ran funeral processions all but ceased in the late 1930s. Following this, they were only used for visitors on Sundays and Mother's Day. The service was briefly revived during World War II during petrol rationing. The last railway timetable was recorded in 1947 and read Sydney 2.17 p.m. to Strathfield 2.33 p.m. to Rookwood #1, 2.50 p.m.

On 3 April 1948, the service was officially terminated while the spur was recorded as closed on 29 December 1948. The tracks remained until the 1980s, with the line used to transport stonework.

Rookwood Cemetery line stations
Station names are based on the current name of the station, or the name of the station when it was closed.
 Regent Street
 Cemetery Station No. 1
 Cemetery Station No. 2
 Cemetery Station No. 3
 Cemetery Station No. 4

References

Further reading
 The Rookwood Cemetery Line Singleton, C.C. Australian Railway Historical Society Bulletin, February 1960 pp. 17–28

External links
 Rookwood Cemetery line in OpenStreetMap.

Closed railway lines in Sydney
Standard gauge railways in Australia
Railway lines opened in 1864
Railway lines closed in 1948

Rookwood Cemetery railway line


Gary Alan Sargent (born February 18, 1954) is an American former professional ice hockey defenseman who played 402 games in the National Hockey League with the Los Angeles Kings and Minnesota North Stars between 1975 and 1983. Internationally he played for the American national team at the 1976 Canada Cup. A first team all-star and league MVP at Bemidji State University, his professional hockey career was cut short by injuries.

Early life
A member of the Ojibwa (Chippewa) nation, he was born on a reservation. Sargent was also a highly promising high school baseball and gridiron football player, receiving an offer to sign a professional contract with the Major League Baseball Minnesota Twins as well as several college football scholarship offers. However, Sargent decided to pursue a career in hockey instead; his distant cousin Henry Boucha and later his first cousin T. J. Oshie also played in the NHL, while his younger brother Earl Sargent is a former NHL draft choice who played minor league hockey.

Pro career
Sargent was drafted by the Los Angeles Kings with the 48th pick in the 1974 NHL Entry Draft and joined the Kings in 1975 after excelling for the United States national hockey team in the 1973 Ice Hockey World Championship and 1974 World Junior Ice Hockey Championships tournament, where he was voted most valuable defenseman. He was named the Kings outstanding newcomer after his rookie year. He was also a member of the US team at the inaugural 1976 Canada Cup tournament and was voted the Kings defenseman of the year in 1976-77. In the 1977–78 season, Sargent tallied 54 points, had a plus/minus of plus 18 on a team that was minus 2 for the season. However, the Kings failed to re-sign Sargent and he became a free agent.

In the summer of 1978, Sargent signed with his native Minnesota North Stars as a restricted free agent when his contract with the Kings ended. Minnesota had to give up three players to Los Angeles (Rick Hampton, Steve Jensen and Dave Gardner) as compensation, but Sargent quickly became one of his new team's most important defensemen in 1978–79, being on ice for a league-record 53.1 percent of his team's goals that season. Sargent was selected for the 1980 NHL All Star game (in Los Angeles) but was unable to participate due to persistent back and knee problems which eventually forced him to retire prematurely in 1983 after missing most of the previous three seasons.

Post career
Sargent returned to the Los Angeles Kings after retiring as a player. He worked as a talent scout for them in 1986–1988.

Career statistics

Regular season and playoffs

International

References

External links

 Sargent's player profile at HockeyDraftCentral.com

1954 births
Living people
American men's ice hockey defensemen
Bemidji State Beavers men's ice hockey players
Ice hockey players from Minnesota
Indianapolis Racers draft picks
Los Angeles Kings scouts
Los Angeles Kings draft picks
Los Angeles Kings players
Minnesota North Stars players
Native American sportspeople
People from Bemidji, Minnesota
People from Red Lake, Minnesota
Springfield Indians players

Gary Sargent


Keith Bernard Burns (born May 16, 1972) is an American football coach and former professional linebacker and special teams player. He was formerly the Special Teams coordinator for the Washington Redskins of the National Football League.

Early life and high school
Burns was born in Greeleyville, South Carolina. He was raised by his mother, Tracy, in Alexandria, Virginia, as the youngest of four children.
He was a 1990 graduate of T. C. Williams High School in Alexandria, where he won three varsity letters in football, two in basketball, and one in baseball.

College
Burns lettered in football at Navarro Junior College in Corsicana, Texas, where he garnered first-team JuCo All-America honors, and finished his sophomore season with six sacks, three interceptions, and 192 tackles.

Burns then transferred to Oklahoma State  for the 1992-1993 season and immediately made an impact with 126 tackles (102 solo), 5 sacks, and 3 forced fumbles.  He was voted captain of the team after just four games and was named the Big Eight Conference's Defensive Newcomer of the Year.  Entering his final year at Oklahoma State, he made several pre-season All-America teams and was ranked the No. 1 inside linebacker by The Sporting News.  He was named to the conference's All-Big Eight team both of his years there.

Playing career
The Denver Broncos drafted Burns in the seventh round (#210 overall) of the 1994 NFL Draft. A Bronco for most of his thirteen-year career, Burns saw playing time as a reserve linebacker and a prominent special teams player. He spent the 1999 season with Chicago Bears, and the 2004 season with Tampa Bay Buccaneers. He won two Super Bowls with the Broncos.  For his entire NFL career, Burns played 197 games (3 starts) and totaled 231 special-teams tackles. He also posted 77 career defensive stops (50 solo), 1.5 sacks (9 yds.), one interception (15 yds.), three pass breakups and one forced fumble.

Coaching career
On March 27, 2007, the Broncos announced Burns would retire as Special Teams Captain and assume the role of instructing the special teams.  He was given the title of Assistant Special Teams Coach in 2011.

Burns was hired by the Washington Redskins to be their Special Teams Coordinator on February 11, 2013. In moving to Washington, he rejoined Mike Shanahan who was his coach in Denver and who also gave Burns his first coaching job. In his first coaching position Keith Burns' Special Teams unit struggled during 2013 season. According to Football Outsiders, under Burns' leadership, the Washington Redskins' Special Teams unit finished the 2013 regular season ranked last in points compared to league average. After less than a year in the position, Keith Burns was dismissed by the Washington Redskins on December 30, 2013, along with Mike Shanahan.

Personal life
Burns met his wife, Michelle, at college.  They have three children together.  His oldest daughter, Danielle is a star for the women's basketball team at Fordham University, wearing number 22. Danielle earned her masters in just four years, having graduated in three years. His other daughter Rachel is currently a member of Charleston Southern. His son Keith is still in High School. In Keith Burns' off time, he has performed stand-up comedy routines around the country.

References

External links
 Tennessee State profile

1972 births
Living people
American football linebackers
Chicago Bears players
Denver Broncos coaches
Denver Broncos players
Los Angeles Chargers coaches
Navarro Bulldogs football players
Oklahoma State Cowboys football players
Tampa Bay Buccaneers players
Tennessee State Tigers football coaches
Washington Redskins coaches
T. C. Williams High School alumni
Sportspeople from Alexandria, Virginia
People from Williamsburg County, South Carolina
Coaches of American football from Virginia
Players of American football from Virginia
African-American coaches of American football
African-American players of American football
21st-century African-American sportspeople
20th-century African-American sportspeople

Keith Burns (linebacker)


Lake Mungo is a dry lake in the south-western part of New South Wales, Australia. It is about 760 km due west of Sydney and 90 km north-east of Mildura. The lake is the main feature of Mungo National Park. It is one of 17 lakes in the World Heritage listed Willandra Lakes Region.

Many important archaeological discoveries have been made at the lake. This includes Mungo Man, the oldest human remains found in Australia,  and Mungo Lady, the oldest human remains in the world to be ritually cremated.

It is also the site of the Lake Mungo geomagnetic excursion, the first convincing evidence that Geomagnetic excursions are a geomagnetic phenomenon rather than sedimentological.

Geology

Sediments at Lake Mungo have been deposited over more than 100,000 years. On the eastern shore of the lake are the 'Walls of China'. These are a 26 km long series of lunettes, about 30 metres high, formed over thousands of years. There are three distinct layers of sands and soil forming the Walls. The oldest is the reddish Gol Gol layer, formed between 100,000 and 120,000 years ago. The middle greyish layer is the Mungo layer, deposited between 50,000 and 25,000 years ago. The most recent is the Zanci layer, which is pale brown, and was laid down between 25,000 and 15,000 years ago.

The Mungo layer, which was deposited before the last ice age period, is the most archaeologically rich. It was a time of low rainfall and cooler weather, but more rainwater ran off the western side of the Great Dividing Range, keeping the lake full. It supported a large human population, as well as many varieties of Australian megafauna.

During the last ice age period, the water level in the lake dropped, and it became a salt lake. This made the soil alkaline, which helped to preserve the remains left behind in the Walls of China. Although the lake completely dried up several thousand years ago, ground vegetation remained on the Walls. This which helped to stabilise them and preserve them. With the arrival of European settlers in the area in the 1880s, introduced species, mostly rabbits, sheep and goats have destroyed the vegetation cover. This has led to increased erosion of the dunes. However, this erosion has led to the uncovering of many human and animal remains. Wind has moved sand and soil eastwards from the Walls, forming a mobile sand dune which moves further east every year.

Archaeology
The most important findings at Lake Mungo have been Mungo Man and Mungo Lady. Mungo Lady, a partly cremated body, was discovered in 1969 by Dr Jim Bowler from the Australian National University (ANU). At first she was thought to be 25,000 years old. A more recent study in 2003 found that she was probably closer to 40,000 years old. Mungo Lady is the earliest known human to have been cremated. Mungo Man was also discovered by Dr Bowler, on 26 February 1974. The remains were covered with red ochre, in what is the earliest known incidence of such a burial practice. Although some studies have shown his age at more than 60,000 years, the current agreement is that he is also about 40,000 years old.

Humans have been living around Lake Mungo for at least 50,000 years. Stone tools have been found in the dunes which are older than the Mungo Man. Grinders for making flour have been found which are between 5,000 and 10,000 years old; they were made of sandstone sourced from the

Murray River basin 100 km away. A stone axe head, at least 500 years old, was also found in the dunes; it was made from stone from Mount Camel, near Shepparton, well over 300 km away.

The rich archaeological heritage of the site is very significant to the Aboriginal Australian people from the area. The Willandra region is home to the Barkindji, Nyiampaa and Mutthi Mutthi people. They have Joint Management Agreements with the Government of New South Wales to manage the lake and the Mungo National Park.

Lake Mungo Geomagnetic Excursion
In 1972, Archaeomagnetic studies were carried out on the prehistoric aboriginal fireplaces found along the ancient shoreline of Lake Mungo. Magnetization preserved in oven-stones and baked hearths show that the axial dipole field moved up to 120 degrees from its normal position around 30,000 years ago. This is called a geomagnetic excursion. Because most of the excursions found before Lake Mungo were in sedimentary material, it had been thought that the magnetic field directional anomalies were detrital or diagenetic in origin. The Lake Mungo results were due to thermoremanent magnetization, ruling out a sedimentological phenomena.

Two excursions have been recorded in sediments from Skjonghelleren on Valderøy, Norway. The Virtual Geomagnetic Pole (VGP) of one happened at the same time as Lake Mungo which suggests the event was global rather than local. Data from lake sediments of a similar age in France having near identical magnetic field lines also support Lake Mungo being a global event. However, it has been suggested that Lake Mungo's anomalous field is the result of lightning strikes.

References

Lakes of Australia
Archaeological sites in Australia

Lake Mungo


Mark Hill Dunnell (July 2, 1823 – August 9, 1904) was a member of the U.S. House of Representatives from Minnesota from 1871 to 1883 and from 1889 to 1891.

Biography
Born in Buxton, York County, Maine, he completed preparatory studies, and was graduated from Waterville College (now Colby College), Waterville, Maine, in 1849. For five years he was principal of the Norway and Hebron Academies. He became a member of the Maine House of Representatives in 1854 and served in the Maine Senate in 1855. He served as state superintendent of common schools in 1855 and 1857 – 1859. He was a delegate to the Republican National Convention in 1856. He studied law, was admitted to the bar in 1856 and commenced practice in Portland, Maine, in 1860. He entered the Union Army as colonel of the 5th Maine Volunteer Infantry Regiment, May 6, 1861, but mustered out on August 31, 1861. He served as United States consul at Vera Cruz, Mexico, in 1861 and 1862.

Dunnell moved to Minnesota in 1865, settling first in Winona, in 1865, and moving to Owatonna in 1867. He became a member of the Minnesota House of Representatives in 1867 and served as state superintendent of public instruction from April 2, 1867, to August 1870, when he resigned.

He was elected as a Republican to the 42nd, 43rd, 44th, 45th, 46th, and 47th Congresses, (March 4, 1871 – March 3, 1883); unsuccessful candidate for Speaker of the Forty-Seventh Congress; was not a candidate for renomination in 1882; unsuccessful candidate for election to the United States Senate in 1883; elected to the 51st Congress, (March 4, 1889 – March 3, 1891); unsuccessful candidate for reelection in 1890 to the 52nd Congress; delegate to the Republican National Convention in 1892.

He was one of the founders and a member of the board of trustees of Minnesota Academy, a high school for boys and girls in Owatonna, being renamed Pillsbury Academy in 1887, and becoming a military academy for high school boys only in 1920.

Dunnell died in Owatonna in 1904 and is buried in Forest Hill Cemetery. He is the namesake of the city of Dunnell, Minnesota.

References

Minnesota Legislators Past and Present
 Retrieved on 2008-10-18

1823 births
1904 deaths
Colby College alumni
Members of the Minnesota House of Representatives
Republican Party members of the Maine House of Representatives
Republican Party Maine state senators
Maine lawyers
Minnesota lawyers
People of Maine in the American Civil War
People from Buxton, Maine
Union Army colonels
Republican Party members of the United States House of Representatives from Minnesota
19th-century American politicians
People from Owatonna, Minnesota
Military personnel from Minnesota

Mark H. Dunnell


Nikolai Nikolayevich Tcherepnin (Russian: Николай Николаевич Черепнин;  – 26 June 1945) was a Russian composer, pianist, and conductor.  He was born in Saint Petersburg and studied under Nikolai Rimsky-Korsakov at the Saint Petersburg Conservatory. He conducted for the first Paris season of Sergei Diaghilev's Ballets Russes.

Life
Nikolai Tcherepnin was born in 1873 to a well-known and wealthy physician of the same name. The elder Nikolai moved in elite circles of artists including Fyodor Dostoyevsky and Modest Mussorgsky. Young Nikolai's mother died when he was a baby, and when his father remarried, was replaced by an ambivalent stepmother. As a child, Nikolai's father beat him regularly and enforced a general code of strict discipline.

At his father's insistence, Nikolai earned a law degree, though during this time he composed steadily.  In 1895 he graduated with his degree in law from the University of Saint Petersburg.  In 1898, he earned a degree in composition under Nikolai Rimsky-Korsakov and a degree in piano under K.K. Fan-Arkh. His talents and high family status earned him a job as the orchestral teacher at the Court Chapel in 1899.  For six years he taught there before returning to the St. Petersburg Conservatory to teach there.  During his 13-year tenure (from 1909 onward as professor) he taught many notable students, including Sergei Prokofiev, Aleksandr Gauk, Yuri Shaporin and Lazare Saminsky.

In 1902 he became the regular conductor of the Russian Symphony Concerts and later made guest appearances with the Russian Musical Society, the Moscow Philharmonic Society, the Siloti Concerts and Ivan Vasilenko's Historic Concerts as well conducting at the Mariinsky Theatre (1906–9). A member of the Belyayev circle, he was also involved with the Kruzhok sovremennoy muzïki ('The Contemporary Music Circle') and worked with the Mir iskusstva ('World of Art') movement. Tcherepnin was a friend of the musicologist Alexander Ossovsky.

In 1907, during his time at the Conservatory, he wrote possibly his most famous work, the ballet Le Pavillon d'Armide. Two years later, Tcherepnin conducted the ballet at the premiere performance of Diaghilev's legendary Ballets Russes. He conducted for the entire first season and returned to conduct multiple times over the next five years. He conducted performances with the Ballets Russes in Berlin, Monte Carlo, Paris, Rome, and the Royal Opera House at Covent Garden in London. In addition to his professorship and his commitments with the Ballet, in 1908, he became conductor at the Mariinsky Theatre.  At this post, he directed the Paris premiere of Rimsky-Korsakov's opera The Golden Cockerel.

From 1905 to 1917, he was principal of the conservatory of St. Petersburg, where he taught conducting. In 1918 he was invited to take the post of director of the National Conservatory of Tbilisi, the capital of the Democratic Republic of Georgia. Following the Bolshevik takeover of Georgia in 1921, he moved to Paris and lived there for the rest of his life. While in France, he worked with Anna Pavlova and her ballet troupe as composer and conductor (1922–4) and made concert tours around Europe and the United States but abandoned his concert career in 1933 because of a deterioration in his hearing. In 1925 he founded the Russian Conservatory in Paris and served as its director for a number of years (1925–9 and 1938–45). In 1926 he became a member of the board of trustees of the Belyayev publishing house, where he later became president from 1937 until his death in 1945.

He was the father of the composer and pianist Alexander Tcherepnin.

Works

Opera
The Matchmaker (1930)
Vanka the Steward (1933)

Ballet
Le Pavillon d'Armide (1907)
Narcisse et Echo (1911)
The Masque of the Red Death (1915)
Bacchus (1922)
A Magical Russian Fairytale (1923)
The Romance of the Mummy (1924)

Choral
2 Choruses (1899)
The Song of Sappho (1899)
The Descent of the Virgin Mary to Hell oratorio, 1934)

Orchestral
La princesse lointaine (prelude to a play of the same name by Edmond Rostand), Op. 4 (1896)
Macbeth (after act 4, scene 1), Op. 12 (1902)
From Land to Land (1903)
Piano Concerto in C-sharp minor, Op. 30 (1905)
Mar'ya Morevna (symphonic poem) (1909)
The Enchanted Kingdom (1910)
6 Musical Illustrations to Pushkin's "Tale about the Fisherman and the Fish" (1917)
Destiny (1938)

Chamber music
Lyrical Poem, for string quartet (1898)
Melody, for violin and piano (1902)
5 Pieces for Piano (1904)
6 Horn Quartets (1910)
The Alphabet in Pictures, for Piano (1910)
Cadence fantastique, for Violin and Piano (1915)

Orchestrations and completions
Modest Mussorgsky: Sorochyntsi Fair (1923)
Sokolovsky: The Miller-Wizard, Cheat and Matchmaker (1925)

Family
His son Alexander Tcherepnin (1899-1977), grandsons (son of Alexander) Ivan Tcherepnin (1943-1998) and Serge Tcherepnin, and great-grandsons (sons of Ivan) Sergei and Stefan Tcherepnin, are also composers.

References

Sources
 Tcherepnin, Nikolay by Christopher Palmer, in 'The New Grove Dictionary of Opera', ed. Stanley Sadie (London, 1992)
Savenko, Svetlana, et al. "Tcherepnin: (1) Nikolay Tcherepnin".  2002.  New Grove Dictionary of Music and Musicians.  7 June 2008.

External links

 Biography at the Tcherepnin Society website
 Memoirs by Nikolai Tcherepnin at the Tcherepnin Society website

1873 births
1945 deaths
Composers from the Russian Empire
Impressionist composers
Male opera composers
Pianists from the Russian Empire
Academic staff of Saint Petersburg Conservatory
Nikolai
Burials at Sainte-Geneviève-des-Bois Russian Cemetery
Emigrants from the Russian Empire to France
Ballets Russes composers
Conductors (music) from the Russian Empire
Russian male conductors (music)

Academic staff of Tbilisi State Conservatory

Nikolai Tcherepnin