JJ

@JosephJacks_ • 43,978 subscribers

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This is a bacterial flagellar motor … one of nature’s most sophisticated molecular machines - a rotary motor embedded in the cell membrane consisting of ~25-30 protein types totaling 20,000-50,000 atoms in a multi-part structure of rotor, stator, drive shaft, and propeller. Operating at 100-300 Hz (6,000-18,000 RPM) with some species reaching 1,700 Hz (~100,000 RPM) at nearly 100% efficiency, this nanoscale engine features rotor proteins FliG/FliM/FliN forming the C-ring, MotA/MotB stator complexes, FlgG rod protein drive shaft, FliC flagellin propeller filament, and FlgE hook proteins acting as a universal joint, all powered by proton or sodium flow across the membrane generating torque through conformational changes in the stator complexes.

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This is why NVIDIA wins.

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Woah.. Jensen is NOT happy about OpenAI.

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Can we just make Yann LeCun president of AI and call it a day please?

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$This 40-micrometer single-celled organism with zero neurons … hunts, kills, and eats other living creatures using nothing but microtubules and geometry. Lacrymaria olor is a freshwater ciliate found in ponds worldwide and one of the most ferocious predators in microbiology. At rest, it’s a teardrop barely visible to the naked eye. When hunting, it launches a neck-like proboscis up to 30× its body length — 1.5mm in under 30 seconds — whipping it through the water in violent, snaking arcs to locate and strike prey by contact alone. No eyes. No chemotaxis. Pure mechanical search-and-destroy. 1.Anchor. Attaches its rear to debris via adhesive secretion. Body stays planted. 2.Deploy. Head cilia activate. The neck rockets outward along a helical microtubule scaffold, unspooling stored membrane like origami unfolding. 3.Sweep. The neck whips, bends, and buckles through 360° in rapid stochastic bursts — covering ~66% of its strike zone in ~93-second hunting events. 4.Strike. Mechanoreceptor cilia on the head distinguish food from non-food at the instant of contact. 5.Kill. Toxicysts — venom organelles armed with polyketide synthases and L-amino acid oxidases — fire on contact, paralyzing the target. 6.Engulf. The oral apparatus swallows the prey whole via phagocytosis. Sub-second. 7.Reel. The contractile myoneme system hauls prey back through the neck to the cell body. 8.Digest. Enzymatic breakdown in food vacuoles. ~15 seconds. 9.Reset. The neck retracts, repleating its origami perfectly. Rest. Hunt again. Prey: Cyclidium, Tetrahymena, Chilomonas, Halteria, Vorticella, flagellates, amoebae. If it encounters something too large to swallow — Blepharisma, Stentor — it tears chunks out of them. If the neck tip hits debris — instant ciliary reversal and full contraction. Retreat. If the neck tip hits prey — toxicyst discharge, amplified ciliary beating, engulfment. Commit. Two opposite behavioral programs, selected and executed at the point of contact, in a fraction of a second, by a cell with no nervous system. No neurons. No synapses. No action potentials. In 2024, Flaum and Prakash at Stanford published on the cover of Science.. The cell’s membrane is wrapped by 15 stiff helical microtubule ribbons — a cortical cytoskeleton unlike anything in any other known organism. These ribbons form a curved-crease origami. Membrane tucks into precise pleats between ribbons, storing enormous surface area in compact folds. Microtubule sheets spool in multiple layers inside the cell body — nested like a compressed helical accordion. When the cell hunts, the origami unfolds. When it retracts, it refolds. Deployment is controlled by topological singularities — d-cones and twisted domain walls — that act as geometric controllers. The structure can only unfold one way and refold one way. Deterministic deployment from pure geometry. Everything pre-stored, pre-folded, topologically locked. Beneath the microtubule scaffold: a contractile myoneme network of centrin-myosin fibers using unconventional Plasmodium-like actin. The two systems are antagonistic. Cilia pull the neck out along the microtubule rails. The myoneme contracts it back. The tug-of-war across timescales generates the full behavioral repertoire. Neither system alone produces the behavior. It emerges from their coupling!!$