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Video: C.S. Lewis’ View of Evolution & Intelligent Design – John West


OT: F18 Carrier Ops - video http://www.youtube.com/watch?v=nw0gjw1XIIk bornagain77
That term, 'natural selection' is a grotesque misnomer, as 'selection' predicates mind, and act or acts of will. Atheists ought to use a term such as 'natural serendipity', leaving open the question of creation and design by an agent of the propitious context; of which, of course, they, themselves, have not the slightest inkling - except that it must not be God. To the atheist knowledge is fine just left as a blur, where it threatens their nihilistic world-view. Day doan wan no steenkin' philosophy. Axel
OT: Tough, light and strong: Lessons from nature could lead to the creation of new materials - February 14, 2013 Excerpt: For example, at the nanoscale, an abalone shell is made of thousands of layers of "tiles" made of calcium carbonate (more commonly known as chalk), about 10 micrometers across and 0.5 micrometer thick—about one-one hundredth the thickness of a strand of human hair. The irregular stacks of thin tiles refract light to yield the characteristic luster of mother of pearl. They are organized in a highly ordered brick-like structure arranged in the toughest configuration theoretically possible,, A key to the strength of the abalone shell, Meyers said, is a protein adhesive that binds to the top and bottom surfaces of the calcium carbonate tiles. The glue is strong enough to hold layers of tiles firmly together, but weak enough to permit the layers to slip apart, absorbing the energy of a heavy blow in the process. Abalones quickly fill in fissures due to impacts, and they also deposit "growth bands" of organic material during seasonal lulls in shell growth. The growth bands further strengthen the shells. Meyers believes that designs inspired by the structure of the abalone shell could help improve advanced ceramic materials in the future.,,, The interior of the toucan's beak is rigid "foam" made of bony fibers and drum-like membranes sandwiched between outer layers of keratin, the protein that makes up fingernails, hair and horn. The result is solid ?foam? made of air-tight cells that gives the beak additional rigidity. Like a house covered by a shingled roof, the foam is covered with overlapping keratin tiles, each about 50 micrometers in diameter and 1 micrometer thick, which are glued together to produce sheets. Meyers said the bio-composite found in the toucan's beak could inspire the design of ultra-light aircraft and vehicle components.,,, "Natural systems are built from so few elements, yet they use ingenious ways to assemble all these different materials to maximize their properties," ,,, For example, spider silk has both high tensile strength and extensibility. "It's stronger than almost any material," Meyers said. The silk is made of pleated sheets of nanocrystals connected by weak hydrogen bonds and embedded in protein strands. Under low stress, the protein strands uncoil and straighten, much like biopolymers. Under larger stress, the load gets transferred to the nanocrystals. If necessary, some of the hydrogen bonds slip, allowing the structure to stretch without breaking. Silk's reliance on hydrogen bonds for strength suggests that researchers may need to pursue new avenues to engineer stronger materials, Meyers said. Incidentally, similar structures can be found in bone, where sacrificial hydrogen bonds between mineralized collagen fibrils impart excellent fracture resistance. More complex strong structures can be found in everything from wool to whelk eggs. http://phys.org/news/2013-02-tough-strong-lessons-nature-creation.html bornagain77
OT: Even the Cell's Shredder Looks Designed - February 14, 2013 Excerpt: They have established that this machine is irreducibly complex in eukaryotes. Does it have any evolutionary precursors? Quote: "The RNA-binding and threading mechanism used by the exosome in eukaryotes is very similar to that of the exosome in bacteria and archaebacteria that the researchers had structurally characterized in earlier studies. "Although the chemistry of the shredding reaction in eukaryotes is very different from that used in bacteria and archaebacteria, the channeling mechanism of the exosome is conserved, and conceptually similar to the channeling mechanism used by the proteasome, a complex for shredding proteins," says Elena Conti.,,, With this description in mind, several problems become apparent for evolutionary explanations of these machines. First of all, they are already present in bacteria and archaebacteria, presumably the simplest living things. Moreover, the bacterial exosome is chemically different but structurally similar. This means the design is "conserved" but not the ancestry. Then there is another chemically different but structurally similar machine in eukaryotes: the proteasome. These machines all appear to be irreducibly complex. They are composed of multiple parts, each essential for function. They are also essential for life: the article says that "unwanted accumulation of RNAs can be damaging to the cell" and that these complex machines have multiple functions. In addition to shredding excess RNAs, the exosome "processes certain RNA molecules into their mature form." Since all living things rely on DNA translation via RNA molecules (messenger RNAs and transfer RNAs), it is difficult to imagine any putative ancestor getting by without functional exosomes from the very beginning. Maybe that's why the article did not even mention evolution. http://www.evolutionnews.org/2013/02/even_the_cells_1068921.html bornagain77

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