Repeated evolution

Cavitation corrosion is brought about by cavitation damage. It can be seen when the repeated evolution and collapse of tiny air bubbles on material surfaces occurs. Cavitation breaks the stable passive films on materials surfaces, which would easily lead to corrosirMi. 

Contrary to earlier beliefs, floral phyllotaxis patterns are very flexible. The direction is not only from spiral to whorled, but there was repeated evolution of spiral phyllotaxis from whorled in the perianth in basal angiosperms (Endress and Doyle, 2007, 2009 Doyle and Endress, 2011) and there is much evolutionary flexibility of patterns within families, genera or even species (Endress, 1987 Staedler and Endress, 2009). 

That a double perianth was reduced during evolution in many groups of eudicots has long been known. However, in some clades there was also repeated evolution of a double perianth with sepals and petals from a simple perianth with only one kind of organ or a fluctuation between both traits. An example is Caryophyllales sensu lato (APG, 2009), which originally had a simple perianth and a double perianth evolved independently in several families (Brockington et al., 2009), with petals at least in part derived from the androecium (Ronse De Craene, 2008). 

Repeated evolution of floral asymmetry from monosymmetry at several levels within a larger clade... 

Reimann A, Nurhayati N, Backenkohler A, Ober D (2004) Repeated evolution of the pytrolizidine alkaloid-mediated defense system in separate angiosperm lineages. Plant Cell 16 2772-2784... 

Rambla JL, Vera-Sirera F, Blazquez MA, Carbonell J, GraneU A (2010) Quantitation of biogenic tetramines in Arabidopsis thaliana. Anal Biochem 397 208-211 Reimann A, Nurhayati N, Backenkohler A, Ober D (2(XH) Repeated evolution of the pyrroU-zidine alkaloid-mediated defense system in separate angiosperm lineages. Plant CeU 16 2772-2784... 

Conduct the preparation in the fume cupboard. Dissolve 250 g. of redistilled chloroacetic acid (Section 111,125) in 350 ml. of water contained in a 2 -5 litre round-bottomed flask. Warm the solution to about 50°, neutralise it by the cautious addition of 145 g. of anhydrous sodium carbonate in small portions cool the resulting solution to the laboratory temperature. Dissolve 150 g. of sodium cyanide powder (97-98 per cent. NaCN) in 375 ml. of water at 50-55°, cool to room temperature and add it to the sodium chloroacetate solution mix the solutions rapidly and cool in running water to prevent an appreciable rise in temperature. When all the sodium cyanide solution has been introduced, allow the temperature to rise when it reaches 95°, add 100 ml. of ice water and repeat the addition, if necessary, until the temperature no longer rises (1). Heat the solution on a water bath for an hour in order to complete the reaction. Cool the solution again to room temperature and slowly dis solve 120 g. of solid sodium hydroxide in it. Heat the solution on a water bath for 4 hours. Evolution of ammonia commences at 60-70° and becomes more vigorous as the temperature rises (2). Slowly add a solution of 300 g. of anhydrous calcium chloride in 900 ml. of water at 40° to the hot sodium malonate solution mix the solutions well after each addition. Allow the mixture to stand for 24 hours in order to convert the initial cheese-Uke precipitate of calcium malonate into a coarsely crystalline form. Decant the supernatant solution and wash the solid by decantation four times with 250 ml. portions of cold water. Filter at the pump. 

Ethyl 3-amlnopropsnoate (5). To a tu solution of 4 in THF (frem the bromo ester with NaN3 In OMSO) was added a molar equivalent of Ph3P, t 5 equiv of water and a boiling chip (N2 evolution) Alter 8 h at 20°C and evaporation, the residue was treated with El20-hexane and PhaPO was filtered This process was repeated and 5 was distilled at 40-45° and 10.5 torr (83%). 

G.T. Gray III and J.C. Huang, Influence of Repeated Shock Loading on the Substructure Evolution of 99.99 wt.% Aluminum, Mater. Sci. Engrg. AI45 (1991),... 

Cyclic States which are configurations that appear in cycles and are repeatedly visited over the course of the evolution they are the attractor states of the system in the sense that they comprise the set toward which all evolutions ultimately lead. If all states are cyclic then the system is globally reversible. 

Repeat steps 2 and 3 to generate the LST approximation of the temporal evolution. 

History, Evolution and Development of Manual, Automatic, and Airborne Repeating Weapons , Prepd for The Bureau of Ordn, US Navy, US Govt Printing Office, Washington, DC (1951), 1688 pp 4) Collier s Encyd 15, 168-76 (1965) 5) Encycl Britannica 14, 521—26... 

Quaternary 3 Myr Repeated glaciations. North and South America join mass extinctions of large mammals, evolution of Homo rise of civilizations, humans begin to modify biogeochemical cycles... 

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