Saturday, September 21, 2019

Creation Moment 9/21/2019 - Walnut as 3-D Puzzle

..marvel not at the matter... Ecclesiastes 5:8----wouldn't it require intelligence to create a 3-D Puzzle?

"Considering that walnuts are widespread and commercially important, they decided to look at the nuts in detail. They found a unique architecture in the shell called “interlocked packing” that resembles a 3-D puzzle.
The outer protective shells of nuts can have remarkable
toughness and strength, which are typically achieved by a layered arrangement of sclerenchyma cells and fibers with a polygonal form. Here, the tissue structure of walnut shells is analyzed in depth, revealing that the shells consist of a single, never reported cell type: the polylobate sclereid cells. These irregularly lobed cells with concave and convex parts are on average interlocked with 14 neighboring cells. The result is an intricate arrangement that cannot be disassembled when conceived as a 3D puzzle. 
This architecture yields a strong, lightweight material of interest to engineers.
Mechanical testing reveals a significantly higher ultimate tensile strength of the interlocked walnut cell tissue
compared to the sclerenchyma tissue of a pine seed coat lacking the lobed cell structure. The higher strength value of the walnut shell is explained by the observation that the crack cannot simply detach intact cells but has to cut through the lobes due to the interlocking. Understanding the identified nutshell structure and its development will inspire biomimetic material design and packaging concepts. Furthermore, these unique unit cells might be of special interest for utilizing nutshells in terms of food waste valorization, considering that walnuts are the most widespread tree nuts in the world.
An animation movie embedded in the paper illustrates the interlocked packing. Now you know why these nuts sometimes require a hammer to open. There are no layers to peel away like an onion. Instead, the whole shell is held together by interlocking pieces, like a 3-D puzzle.

How does the walnut tree build its puzzle?
--After fertilization of the hanging clusters of flowers that drape down under the opposite-compound leaves, seeds begin to form. --The shells begin to develop inside hard green husks that will split open upon ripening. At first, the the sclerynchyma cells appear rounded, but as they grow, the cell walls show perforations.
--Out of the perforations, the cells bulge outward with usually about 14 protrusions, creating complex 3-dimensional shapes resembling 14-sided figures called tetrakaidecahedrons.
--These form the “unit cells” of the puzzle. Neighboring cells fit into the spaces between the protrusions with their own protrusions, interlocking into a tight, interlocking arrangement.
--Meanwhile, the seed develops into its characteristic wrinkly, bi-lobed shape, supported by thin walls in the center of the shell."
EN&V