Oxaloacetic acid

Oxaloacetic acid is a crystalline organic compound with the chemical formula HO2CCCH2CO2H. Oxaloacetic acid, in the form of its conjugate base oxaloacetate, is a metabolic intermediate in many processes that occur in animals, it takes part in gluconeogenesis, the urea cycle, the glyoxylate cycle, amino acid synthesis, fatty acid synthesis and the citric acid cycle. Oxaloacetic acid undergoes successive deprotonations to give the dianion: HO2CCCH2CO2H ⇌ −O2CCCH2CO2H + H+ pKa = 2.22 −O2CCCH2CO2H ⇌ −O2CCCH2CO2− + H+, pKa = 3.89At high pH, the enolizable proton is ionized: −O2CCCH2CO2− ⇌ −O2CCCHCO2− + H+, pKa = 13.03The enol forms of oxaloacetic acid are stable, so much so that the two tautomers have different melting points. Oxaloacetate forms in several ways in nature. A principal route is upon oxidation of L-malate, catalyzed by malate dehydrogenase, in the citric acid cycle. Malate is oxidized by succinate dehydrogenase in a slow reaction with the initial product being enol-oxaloacetate, it arises from the condensation of pyruvate with carbonic acid, driven by the hydrolysis of ATP: CH3CCO2− + HCO3− + ATP → −O2CCH2CCO2− + ADP + PiOccurring in the mesophyll of plants, this process proceeds via phosphoenolpyruvate, catalysed by pyruvate carboxylase.

Oxaloacetate can arise from trans- or de- amination of aspartic acid. Oxaloacetate is an intermediate of the citric acid cycle, where it reacts with acetyl-CoA to form citrate, catalyzed by citrate synthase, it is involved in gluconeogenesis, the urea cycle, the glyoxylate cycle, amino acid synthesis, fatty acid synthesis. Oxaloacetate is a potent inhibitor of complex II. Gluconeogenesis is a metabolic pathway consisting of a series of eleven enzyme-catalyzed reactions, resulting in the generation of glucose from non-carbohydrates substrates; the beginning of this process takes place in the mitochondrial matrix, where pyruvate molecules are found. A pyruvate molecule is carboxylated by a pyruvate carboxylase enzyme, activated by a molecule each of ATP and water; this reaction results in the formation of oxaloacetate. NADH reduces oxaloacetate to malate; this transformation is needed to transport the molecule out of the mitochondria. Once in the cytosol, malate is oxidized to oxaloacetate again using NAD+.

Oxaloacetate remains in the cytosol, where the rest of reactions will take place. Oxaloacetate is decarboxylated and phosphorylated by phosphoenolpyruvate carboxykinase and becomes 2-phosphoenolpyruvate using guanosine triphosphate as phosphate source. Glucose is obtained after further downstream processing; the urea cycle is a metabolic pathway that results in the formation of urea using two ammonium molecules and one bicarbonate molecule. This route occurs in hepatocytes; the reactions related to the urea cycle produce NADH), NADH can be produced in two different ways. One of these uses oxaloacetate. In the cytosol there are fumarate molecules. Fumarate can be transformed into malate by the actions of the enzyme fumarase. Malate is acted on by malate dehydrogenase to become oxaloacetate, producing a molecule of NADH. After that, oxaloacetate will be recycled to aspartate, as transaminases prefer these keto acids over the others; this recycling maintains the flow of nitrogen into the cell. The glyoxylate cycle is a variant of the citric acid cycle.

It is an anabolic pathway occurring in plants and bacteria utilizing the enzymes isocitrate lyase and malate synthase. Some intermediate steps of the cycle are different from the citric acid cycle; this means that oxaloacetate in this cycle acts as the primary reactant and final product. In fact the oxaloacetate is a net product of the glyoxylate cycle because its loop of the cycle incorporates two molecules of acetyl-CoA. In previous stages acetyl-CoA is transferred from the mitochondria to the cytoplasm where fatty acid synthase resides; the acetyl-CoA is transported as a citrate, formed in the mitochondrial matrix from acetyl-coA and oxaloacetate. This reaction initiates the citric acid cycle, but when there is no need of energy it is transported to the cytoplasm where it is broken down to cytoplasmatic acetyl -CoA and oxaloacetate. Another part of the cycle requires NADPH for the synthesis of fatty acids. Part of this reducing power is generated when the cytosolic oxaloacetate is returned to the mitochondria as long as the internal mitochondrial layer is non-permeable for oxaloacetate.

Firstly the oxaloacetate is reduced to malate using NADH. The malate is decarboxylated to pyruvate. Now this pyruvate can enter the mitochondria, where it is carboxylated again to oxaloacetate by pyruvate carboxylase. In this way, the transfer of acetyl-CoA, from the mitochondria into the cytoplasm produces a molecule of NADH; the overall reaction, spontaneous, may be summarized as: HCO3– + ATP + acetyl-CoA → ADP + Pi + malonyl-CoA Six essential amino acids and three nonessential are synthesized from oxaloacetate and pyruvate. Aspartate and alanine are formed from oxaloacetate and pyruvate by transamination from glutamate. Asparagine, methionine and threonine are synthesized by aspartate, therefore given importance to oxaloacetate as without it, no aspartate would be formed and the following other amino acids would neither be produced. Oxaloacetate produces oxalate by hydrolysis. Oxaloacetate + H2O ⇌ oxalate + acetateThis; this enzyme is not known in the animal kingdom. Dioxosuccinic acid Glycolysis Oxidative phosphorylation Citric acid cycle

Steel Panthers

Steel Panthers is a series of computer wargames and published by several different companies, with various games simulating war battles from 1930 to 2025. The first Steel Panthers game was released in 1995, the most recent update was released in 2018 and is still updated regularly. Players control individual tanks and vehicles from a top-down perspective, on a map with a hexagonal overlay. Infantry are in squad/section sized units, but some units, like snipers, can be controlled individually; the whole force under a players control would be Battalion sized, but may be as small as a Platoon or Company, or as large as a Regiment/Brigade. The games are played against the AI or other humans via email or hotseat; as with other tactical turn-based wargames, the game features realistic military control, with the smallest common units being squads, up to a brigade sized force. The player takes control of nearly every aspects of warfare around his soldiers, from simple ammunition usage, to the morale and command-chain of his troops.

The game features: packed single-battle scenarios and campaigns, single battle generator, campaign generator, long campaign generator. All of the games in the series are quite similar in features and appearance. However, the third part in the original series is distinct in that it offers platoon-size formations instead of the scale of individual tanks and squads of the other installments; the games offer various modes of play: human vs. human, human vs. AI and PBEM; the players receive historical military units at the beginning of a scenario and have the option to buy reinforcements with points earned in different ways. The units are moved on a hexagon grid map similar to a large number of board and computerized wargames. In addition to ready-made battles and campaigns, players can customize single scenarios or create their own campaigns; the Steel Panthers series includes the following titles: 1995 Steel Panthers by Strategic Simulations 1996 Steel Panthers: Campaign Disk by Strategic Simulations 1997 Steel Panthers: Campaign Disk #2 by Strategic Simulations 1996 Steel Panthers II: Modern Battles by Strategic Simulations 1996 Steel Panthers II: Modern Battles - Campaign Disk by Strategic Simulations 1997 Steel Panthers III: Brigade Command: 1939-1999 by Strategic Simulations 1998 SP2WW2 by Camo Workshop 1999 SPWW2 by Camo Workshop 2006 WinSPWW2 by Camo Workshop, Distributed by Shrapnel Games 2000 Steel Panthers: World at War by Matrix Games 2002 SPMBT by Camo Workshop 2005 WinSPMBT by Camo Workshop, Distributed by Shrapnel GamesRights to the game and source code were acquired by both Matrix Games and the Camo Workshop.

Matrix Games developed and released as a freeware a remake based on the Steel Panthers III engine, Steel Panthers: World at War! Steel Panthers was named the best wargame of 1995 by Computer Gaming World, PC Gamer US and Computer Games Strategy Plus; the editors of PC Gamer US called it "easily one of the best tactical simulations developed for the PC."Steel Panthers and Steel Panthers II were named, the 62nd best computer game by PC Gamer UK in 1997. Walker M. H. Games That Sell!. — Wordware Publishing, 2003. — 550 p. —. — ISBN 9781556229503. — ISBN 155622950X. Black M. Kurlander E. Revisiting the «Nazi Occult»: Histories, Legacies. — Boydell & Brewer, 2015. — 297 p. —. — ISBN 9781571139061. — ISBN 1571139060. Steel Panthers series at MobyGames

Fire in the Attic

Fire in the Attic is a German Post-Hardcore band, founded in October 2003 in Bonn. The band features singer Ole Feltes, guitarists Richard Meyer and Daniel Crebelli, bassist Dennis Meyer and drummer Daniel Plotzki. All musicians played in former bands Fastplant; the first CD the band released was the Decision & Action EP in May 2004. In 2004 FITA opened for bands like Coheed and Cambria. In April 2005 the album début Crash/Rebuild followed on the EP; the same year FITA played some support gigs with groups like Taking Back Sunday, Hot Water Music, Millencolin and Boysetsfire. Fire in the Attic played on Rheinkultur 2005 in front of more than 145,000 people. On 2 June 2006 the band released their second studio album I´ll Beat You, City!. The album was published on Cargo Records. In May and June 2006 the band supported Moneen on their German tour. In November 2006 FITA shared stage at the Taste of Chaos 2006s tour with Anti-Flag. On 18 April 2008 the band released their third album Cum Grano Salis. Two days before official release date the whole album was published on German magazine VISIONS and had sold over 87,000 copies.

In August 2008 singer Ole Feltes left FITA. He was replaced by British singer Thomas Prescott of Kenai. On 13 March 2009 the band released their fourth self-titled studio album on Redfield Records. Since 2009 the band paused; the band's musical style was compared with Emocore. FITA is a post-hardcore band with harder and melodic screams since 2008 when Thomas Prescott became lead vocalist of the band; the music was compared with the band Thrice. The band uses influences of modern Emocore. 2004: Decision & Action 2005: Crash/Rebuild 2006: I´ll Beat You, City! 2008: Cum grano Salis 2009: Fire In The Attic Official site