Applications of constrained chaos: Two-dimensional constrained chaos and industrial revolution cycles: "Since the 1760s, at least three industrial revolutions have occurred. To explain this phenomenon, we introduce two-dimensional (2D) constrained chaos. Using a model of innovation dynamics, we show that an industrial-revolution-like technology burst, driven by investment/saving motives for R&D activities, recurs about every one hundred years if the monopolistic use of a new technology lasts about 8 y." Full paper @PNAS.
Researchers have crafted synthetic genomes for several types of bacteria, and an 18-year-long project to do the same for brewer’s yeast is close to completion. Now, a group in China has tackled a multicellular organism, synthesizing part of the genome of a type of moss.Full news article at Science.
Peter Hilton (1923-2010) discusses intriguing number tricks that can be explained by analysing the properties of Fibonacci numbers and the related Lucas numbers. The explanations themselves benefit from further explanations which, in their turn, lead to further discoveries. Recorded at Imperial College London during the 1996 London Mathematical Society Popular Lecture series.
Patterns of Life – D’Arcy Thompson, Structuralism and the Shape of Life
Treasures of the Library 5. D'Arcy Thompson, On growth and form
BLOOMS: Strobe Animated Sculptures Invented by John Edmark from Charlie Nordstrom on Vimeo. "This series of 3D printed sculptures was designed in such a way that the appendages match Fibonacci's Sequence, a mathematical sequence that manifests naturally in objects like sunflowers and pinecones. When the sculptures are spun at just the right frequency under a strobe light, a rather magical effect occurs: the sculptures seem to be animated or alive!"
Diversity of information pathways drives sparsity in real-world networks
"What if the same physics that governs quantum particles could also explain the peculiar patterns observed in protein-protein interactions, in complex brains, in social relationships, in the Internet infrastructure or the intricate web of air traffic routes? This is not science fiction: it is a mathematical framework, based on thermodynamics and information theory, that has been used for decades to describe entanglement in quantum systems." See an explanation in the great Complexity Thoughts newsletter and the full paper at Nature Physics.
"As they collect and analyze massive amounts of genetic sequences from plants, animals, and microbes, biologists keep encountering surprises, including some that may challenge the very definition of life. The latest, reported this week in a preprint, is a new kind of viruslike entity that inhabits bacteria dwelling in the human mouth and gut. " Full News Report @ "Science"
RNA editing is hypothesized to facilitate adaptive evolution via flexibly diversifying the proteome temporally or spatially. However, direct experimental evidence is lacking. This study unveils the functional importance of conserved missense adenosine-to-inosine (A-to-I) RNA editing (CME) sites in Fusarium graminearum and provides convincing experimental evidence for the adaptive advantages of two CME sites. The first CME site drives the CME5 gene gaining a new important function in ascus and ascospore formation during evolution. Having an editable A at this site is fitter than an uneditable A or a genomically encoded G. The second CME site in the CME11 gene confers a “heterozygote advantage” during ascosporogenesis, meaning that concurrently expressing both edited and unedited versions is more advantageous than either. Full article: Xin, Kaiyun, et al. "Experimental evidence for the functional importance and adaptive advantage of A-to-I RNA editing in fungi." Proceedings of the National Academy of Sciences120.12 (2023): e2219029120.
A new take on Ai, is "Wet" AI using organoids and other sythetic biology methods. "We anticipate OI-based biocomputing systems to allow faster decision-making, continuous learning during tasks, and greater energy and data efficiency. Furthermore, the development of “intelligence-in-a-dish” could help elucidate the pathophysiology of devastating developmental and degenerative diseases (such as dementia), potentially aiding the identification of novel therapeutic approaches to address major global unmet needs." Full article @ Frontiers in Science. Thank you Xuanchi Li for the article.
"Laning is a paradigmatic example of spontaneous organization in active two-component flows that has been observed in diverse contexts, including pedestrian traffic, driven colloids, complex plasmas, and molecular transport. We introduce a kinetic theory that elucidates the physical origins of laning and quantifies the propensity for lane nucleation in a given physical system. Our theory is valid in the low-density regime, and it makes different predictions about situations in which lanes may form that are not parallel with the direction of flow. We report on experiments with human crowds that verify two notable consequences of this phenomenon: tilting lanes under broken chiral symmetry and lane nucleation along elliptic, parabolic, and hyperbolic curves in the presence of sources or sinks." Full article @ Science.
We propose a biologically plausible model, based on a variant of the reinforced random walk on a graph, which explains this observation and suggests surprising algorithms for the shortest path problem and its variants. Full paper @ PNAS.
Scientists created DNA nanotube rails that branch in multiple directions, with each unique track made up of unique DNA patterns. Protein motors designed to recognize these patterns then carry their cargo down the desired tracks. Nanoswitchyards should help scientists better test and understand the real thing inside cells. They may also eventually help researchers steer different drug cargoes to different tissues or engineer novel DNA computers that respond to their environment. In the video, proteins called dyneins have been engineered to glide along DNA tracks. At a branch point, different DNA patterns of the tracks steer dyneins carrying orange fluorescent cargo to the left and dyneins carrying cyan fluorescent compounds to the right.
3D underwater collective behaviors in a fish-inspired robot swarm
"most underwater robot collectives rely on centralized, above-water, explicit communication and, as a result, exhibit limited coordination complexity. Here, we demonstrate 3D collective behaviors with a swarm of fish-inspired miniature underwater robots that use only implicit communication mediated through the production and sensing of blue light. We show that complex and dynamic 3D collective behaviors—synchrony, dispersion/aggregation, dynamic circle formation, and search-capture—can be achieved by sensing minimal, noisy impressions of neighbors, without any centralized intervention." Full paper @ Science Robotics.
Exciting work bridging biology and computing from josh Bongard and Michael Levin, who "present a method that designs completely biological machines from the ground up: computers automatically design new machines in simulation, and the best designs are then built by combining together different biological tissues." Full article @ PNAS.
"A yellow organism which looks like fungus but acts like an animal has gone on display at the Paris Zoological Park. The slime mould - Physarum polycephalum - has almost 720 sexes and has been described as one of "nature's mysteries" by scientists. It can heal itself in two minutes if cut in half, and detect and digest food despite not having eyes, a mouth or a stomach." From BBC News.
"A robotic system has been demonstrated in which the random motion of individual components leads to deterministic behaviour, much as occurs in living systems. Environmental and medical applications could follow." News article and full paper @ Nature.
"Novelty detection is a fundamental biological problem that organisms must solve to determine whether a given stimulus departs from those previously experienced. [The authors show] the algorithmic basis of an important neurobiological problem and offers strategies for novelty detection in computational systems." Full paper @ PNAS.
"A common theme in the self-organization of multicellular tissues is the use of cell-cell signaling networks to induce morphological changes. We used the modular synNotch juxtacrine signaling platform to engineer artificial genetic programs in which specific cell-cell contacts induced changes in cadherin cell adhesion. Despite their simplicity, these minimal intercellular programs were sufficient to yield assemblies with hallmarks of natural developmental systems: robust self-organization into multi-domain structures, well-choreographed sequential assembly, cell type divergence, symmetry breaking, and the capacity for regeneration upon injury. The ability of these networks to drive complex structure formation illustrates the power of interlinking cell signaling with cell sorting: signal-induced spatial reorganization alters the local signals received by each cell, resulting in iterative cycles of cell fate branching. These results provide insights into the evolution of multi-cellularity and demonstrate the potential to engineer customized self-organizing tissues or materials."
" By combining three-dimensional electron tomography with two-dimensional electron microscopy, Reznikov et al. observed structural ordering from the nanoscale upward. At the smallest scale, needle-shaped mineral units form platelets that organize into stacks bridging multiple collagen units." Full article @ Science.
"Most robots stick out in nature like a sore thumbdrive. Now, scientists have found a new way to help them blend in—by changing not only the color, but also the texture of their skin. Inspired by cephalopods—squid, octopus, and cuttlefish—which use ring-shaped muscles to squeeze small bumps on their skin into large bulges that mimic rocks and algae, researchers created similar reversible protrusions with sheets of stretchy silicone. " Full news @ Science.
"Even asking how much the body contributes to intelligent action presupposes a division between brain and body that seems not to apply to the octopus. The octopus’s body is pervaded by nervousness: it is not a thing controlled by the animal’s thinking part, but itself a thinking thing". Full book review at London Review of Books. Thank you to Thiago Carvalho for sharing.
"[...] many math sculptors also aim to connect their pieces to the observable, natural world. A gypsum sculpture by David Bachman, for example, looks just like a seashell in both shape and color. But it’s wholly artificial: Bachman first drew—on a computer screen—a curve representing the profile of the shell. Then, he used a computer program to generate equations to describe the spiral shape seen on the outside, as well as the twisting internal structure. Bachman sent his design to a 3D printer, and a convincingly real shell emerged layer by layer. It’s so convincing that the first thing people do when they see it, he says, is put it to their ear. “I wanted to prove the point that you can create a very natural looking thing with mathematics,” he says." Full article at PNAS.
DNA Fountain approaches the theoretical maximum for information stored per nucleotide. Efficient encoding of information is demonstrated by storing a full computer operating system, movie, and other files with a total of 2.14 × 106 bytes in DNA oligonucleotides and perfectly retrieved the information after multiple rounds of polymerase chain reaction. Full paper @ Science
Efficient Switches in Biology and Computer Science
"Biological systems are adapted to respond quickly to changes in their environment. Signal processing often leads to all-or-none switch-like activation of downstream pathways. Such biological switches are based on molecular interactions that form positive feedback loops. [...] We discuss here how the structure and dynamical features of a computational algorithm resemble the behaviour of a large class of biological switches and what makes them work efficiently." Full article @ PLOS Computational Biology