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Continuous casting, also called strand casting, is the process whereby molten metal is solidified into a "semifinished" billet, bloom, or slab for subsequent rolling in the finishing mills. Prior to the introduction of continuous casting in the 1950s, steel was poured into stationary molds to form ingots .
For example, one study [12] used serial passage in baboons to create a strain of HIV-2 that is particularly virulent to baboons. Typical strains of HIV-2 only infect baboons slowly. [ 12 ] This specificity makes it challenging for scientists to use HIV-2 in animal models of HIV-1, because the animals in the model will only show symptoms slowly.
The outer circle demonstrates steps in a typical experiment. The red symbols indicate functional variants, the pale symbols indicate variants with reduced function. Directed evolution ( DE ) is a method used in protein engineering that mimics the process of natural selection to steer proteins or nucleic acids toward a user-defined goal. [ 1 ]
The pygmy mammoth is an example of insular dwarfism, a case of Foster's rule, its unusually small body size an adaptation to the limited resources of its island home.. A biological rule or biological law is a generalized law, principle, or rule of thumb formulated to describe patterns observed in living organisms.
This example of design experiments is attributed to Harold Hotelling, building on examples from Frank Yates. [21] [22] [14] The experiments designed in this example involve combinatorial designs. [23] Weights of eight objects are measured using a pan balance and set of standard weights. Each weighing measures the weight difference between ...
Waddington used the concept of canalisation to explain his experiments on genetic assimilation. [3] In these experiments, he exposed Drosophila pupae to heat shock. This environmental disturbance caused some flies to develop a crossveinless phenotype. He then selected for crossveinless. Eventually, the crossveinless phenotype appeared even ...
Griffith's experiment discovering the "transforming principle" in Streptococcus pneumoniae (pneumococcal) bacteria. Griffith's experiment, [1] performed by Frederick Griffith and reported in 1928, [2] was the first experiment suggesting that bacteria are capable of transferring genetic information through a process known as transformation.
The classic example of genetic assimilation was a pair of experiments in 1942 and 1953 by Waddington. He exposed Drosophila fruit fly embryos to ether, producing an extreme change in their phenotype: they developed a double thorax, resembling the effect of the bithorax gene. This is called a homeotic change.