LEGO bricks are commercially available interlocking pieces of plastic that are conventionally used as toys. We describe their use to build engineered environments for cm-scale biological systems, in particular plant roots. Specifically, we take advantage of the unique modularity of these building blocks to create inexpensive, transparent, reconfigurable, and highly scalable environments for plant growth in which structural obstacles and chemical gradients can be precisely engineered to mimic soil.
Lind, K., Sizmur, T., Benomar, S., Miller, A., & Cademartiri, L. (2014). LEGO® Bricks as Building Blocks for Centimeter-Scale Biological Environments: The Case of Plants PLoS ONE, 9 (6) DOI: 10.1371/journal.pone.0100867
Even Nobel Prize winners like to play with Legos. Here, Peter Higgs — theorist of the eponymous Higgs particle — signs a Lego scale model of the ATLAS detector, which was instrumental in tracking down the particle that carries his name (and endows some particles with mass).
Yonggang Ke, Luvena L. Ong, William M. Shih, Peng Yin described an interesting brick model for the DNA that is analogous to LEGO® brick structures:
We describe a simple and robust method to construct complex three-dimensional (3D) structures by using short synthetic DNA strands that we call “DNA bricks.” In one-step annealing reactions, bricks with hundreds of distinct sequences self-assemble into prescribed 3D shapes. Each 32-nucleotide brick is a modular component; it binds to four local neighbors and can be removed or added independently. Each 8–base pair interaction between bricks defines a voxel with dimensions of 2.5 by 2.5 by 2.7 nanometers, and a master brick collection defines a “molecular canvas” with dimensions of 10 by 10 by 10 voxels. By selecting subsets of bricks from this canvas, we constructed a panel of 102 distinct shapes exhibiting sophisticated surface features, as well as intricate interior cavities and tunnels.
The first picture was extracted from the divulgative article:
(A) A DNA brick consists of four regions of 8 nucleotides each and corresponds to a two-stud LEGO brick. Half–DNA-bricks corresponding to one-stud LEGO bricks are used for edges. DNA bricks are connected by an 8–base pair hybrid, causing a 90° shift between two layers. (B) Ke et al. used one- and two-stud bricks (represented by the LEGO bricks in the blue frame) to assemble a 10 by 10 by 10 voxel cuboid (C). With subsets of the bricks used for the cuboid, the authors also assembled many other shapes, such as a space shuttle–like structure, shown both as a LEGO (D) and DNA model (E). The extra bricks in the red-framed section in (B) are the boundary and protector bricks required for formation of the space shuttle structure.
The second image is extracted from the research paper:
Ke Y., Ong L.L., Shih W.M. & Yin P. (2012). Three-Dimensional Structures Self-Assembled from DNA Bricks, Science, 338 (6111) 1177-1183. DOI: 10.1126/science.1227268
A Turing machine is a device that manipulates symbols on a strip of tape according to a table of rules. Despite its simplicity, a Turing machine can be adapted to simulate the logic of any computer algorithm, and is particularly useful in explaining the functions of a CPU inside a computer.
The “Turing” machine was described by Alan Turing in 1936,(1) who called it an “a(utomatic)-machine”. The Turing machine is not intended as a practical computing technology, but rather as a hypothetical device representing a computing machine. Turing machines help computer scientists understand the limits of mechanical computation.
If you want, you can read my posts dedicated to Alan Turing on Doc Madhattan (english) and DropSea (italian)
(1) Turing, A.M. (1937). On Computable Numbers, with an Application to the Entscheidungsproblem, Proceedings of the London Mathematical Society, s2-42 (1) 265. DOI: 10.1112/plms/s2-42.1.230 (scan version)