# gst: liquid–liquid phase transition, the two forms of liquid water (mixed with the natural antifreeze trehalose)

<< Liquids are structurally disordered, so it’s not immediately obvious how they can support two distinct structures with different densities. But that does seem to be possible for liquids in which some degree of directional bonding, such as hydrogen bonds between adjacent water molecules, makes distinct local structures possible. Liquid–liquid transitions have been reported, for example, in silicon, gallium, phosphorus and silicates. But finding one in supercooled water has proved very challenging. There have been previous claimed observations of a liquid–liquid transition in aqueous solutions at ambient pressure, (..) where the solute, such as the sugar glycerol, sometimes used as a cryoprotectant, lowers the freezing point. But such claims have been disputed.(..) Other researchers have reported liquid-like behaviour as the two well-established high- and low-density forms of amorphous (glass-like) ice interconvert. (..) >>

<< In 2014 Yoshiharu Suzuki (..) working with veteran water researcher Osamu Mishima, reported possible signs of a liquid–liquid transition, ending in a critical point where the two liquid states become indistinguishable, in emulsified, supercooled solutions of glycerol. (..) They saw signs of two distinct disordered states with different densities at a temperature of 150K. But there was no direct evidence that both were liquids, rather than amorphous ice. >>

<< Suzuki has now explored the same approach using trehalose as the solute – a sugar produced as a natural cryoprotectant by some organisms, such as insects, that experience extreme cold, to prevent their blood from freezing. He pressurised dilute emulsified solutions to about 0.6GPa at a range of temperatures below 159K, and then decompressed them again.  >>

<< Such hysteresis – whereby the density jumps at different pressures on compression and decompression – is normal for a first-order transition where a parameter such as density changes discontinuously. It reflects the fact that the transition has to start with the chance formation of a ‘nucleus’ of the new phase, which then grows. >>

<< Suzuki is not yet sure why trehalose stabilises water so well against crystallisation, compared with glycerol – but this might help explain why life uses it as an antifreeze. >>

Philip Ball. Direct evidence emerges for the existence of two forms of liquid water. Feb 1, 2022.

https://www.chemistryworld.com/news/direct-evidence-emerges-for-the-existence-of-two-forms-of-liquid-water/4015144.article  

Also

keyword 'water' in FonT

https://flashontrack.blogspot.com/search?q=water

keyword 'transition' | 'transitional' in FonT

https://flashontrack.blogspot.com/search?q=transition

https://flashontrack.blogspot.com/search?q=transitional

keyword 'transition' | 'transizion*' in Notes (quasi-stochastic poetry)

https://inkpi.blogspot.com/search?q=transition

https://inkpi.blogspot.com/search?q=transizione

https://inkpi.blogspot.com/search?q=transizioni

keywords: gst, transition, liquid-liquid transition, water

# chem: more on the weirdness of water, "T" and "non-T" Tetrahedral arrangements

<< the unusual properties of liquid water, if compared with other liquids, has puzzled us for centuries because the basic structure of liquid water has remained unclear and has continued to be a matter of serious debate. >>

AA << show that there are two overlapped peaks hidden in the apparent “first diffraction peak” of the structure factor. One of them (ordinary peak) corresponds to the neighboring O–O [Oxygen-Oxygen bond] distance as in ordinary liquids, and the other (anomalous peak) corresponds to a longer distance. >>

the << anomalous peak arises from the most extended period of density wave associated with a tetrahedral water structure and is to be identified as the so-called first sharp diffraction peak >>

<< In contrast, the ordinary peak arises from the density wave characteristic of local structures lacking tetrahedral symmetry. This finding unambiguously proves the coexistence of two types of local structures in liquid water. >>

Rui Shi, Hajime Tanaka. Direct Evidence in the Scattering Function for the Coexistence of Two Types of Local Structures in Liquid Water. J. Am. Chem. Soc. doi: 10.1021/ jacs.9b11211. Jan 21, 2020. 

https://pubs.acs.org/doi/10.1021/jacs.9b11211#

Water, water everywhere—and it's weirder than you think. University of Tokyo. Feb 4, 2020.

https://m.phys.org/news/2020-02-everywhereand-weirder.html

# s-chem: more on the anomalous properties of water

<< Most of us know that water is essential for our existence on planet Earth. It is less well-known that water has many strange or anomalous properties and behaves very differently from all other liquids >>

<< Some examples are the melting point, the density, the heat capacity, and all-in-all there are more than 70 properties of water that differ from most liquids >>

<< These anomalous properties of water are a prerequisite for life as we know it >>

<< "The new remarkable property is that we find that water can exist as two different liquids at low temperatures where ice crystallization is slow" >> Anders Nilsson.

Water exists as two different liquids. June 26, 2017.

https://m.phys.org/news/2017-06-liquids.html

Fivos Perakisa, Katrin Amann-Winkela, et al. Diffusive dynamics during the  high-to-low density transition in amorphous ice. PNAS 2017 doi: 10.1073/pnas.1705303114.

http://m.pnas.org/content/early/2017/06/23/1705303114

# phyto: feel sounds to spot water

AA << used the model plant Pisum sativum to investigate the mechanism by which roots sense and locate water >>

AA << found that roots were able to locate a water source by sensing the vibrations generated by water moving inside pipes, even in the absence of substrate moisture. When both moisture and acoustic cues were available, roots preferentially used moisture in the soil over acoustic vibrations, suggesting that acoustic gradients enable roots to broadly detect a water source at a distance, while moisture gradients help them to reach their target more accurately >>

AA << results also showed that the presence of noise affected the abilities of roots to perceive and respond correctly to the surrounding soundscape >>

Monica Gagliano, Mavra Grimonprez, et al. Tuned in: plant roots use sound to locate water. Oecologia. Volume 184, Issue 1, pp 151–160. May 2017

https://link.springer.com/article/10.1007%2Fs00442-017-3862-z

# s-astro: old, very old water

<< As much as half of all the water on Earth may have come from that interstellar  gas  according  to astrophysicists ’ calculations. That means the same liquid we drink and that fills  the  oceans  may be millions  of  years  older  than the  solar  system  itself. >>

Nicholas St. Fleur. The Water in Your Glass Might Be OlderThan the Sun.  April 15, 2016

http://www.nytimes.com/2016/04/16/science/the-water-in-your-glass-might-be-older-than-the-sun.html

L.  Ilsedore  Cleeves ,  Edwin  A.  Bergin ,  et al. The  ancient  heritage  of  water  ice  in  the  solar  system. Science    26 Sep 2014: Vol.  345,  Issue  6204,  pp.  1590-1593 DOI:  10.1126/science.1258055

http://science.sciencemag.org/content/345/6204/1590

# qubit: an energy control approach to build quantum computers: quickly jump two rungs at a time without spilling any water from the glass

<< Dr. Sergey Danilin, (..) describes quantum control-the process of using chips like transmons to build quantum computers-by extending the "climbing a ladder" analogy. "To get a useful quantum system, you need to imagine climbing a ladder while holding a glass of water-it works if one does it smoothly, but if you do it too fast, the water spills. Certainly, this requires a special skill."  (..)  in the quantum world, the trick for climbing the ladder quickly without spilling any water is by carefully jumping two rungs at a time. >>

Life on the edge in the quantum world. Aalto University. Feb 8, 2019

https://m.phys.org/news/2019-02-life-edge-quantum-world.html

Antti Vepsalainen, Sergey Danilin,  Gheorghe Sorin Paraoanu. Superadiabatic population transfer in a three-level superconducting circuit. Science Advances  Feb 8, 2019:
Vol. 5, no. 2, eaau5999
doi: 10.1126/sciadv.aau5999

http://advances.sciencemag.org/content/5/2/eaau5999

Also

https://flashontrack.blogspot.com/search?q=%23+qubit

# gst: to find a separation between plunging and spilling wave breakers

<< While understanding breaking waves is crucial for the development of parametrizations used in ocean wave modeling for both deep and shallow water, the complete process of wave breaking is not well understood. Here (AA) present direct numerical simulations of two-dimensional solitary waves that shoal and break on a uniform beach in shallow water, with the presence of storm surge represented by an inshore region. >>️

They << classify wave breaker types and find a separation between plunging and spilling breakers when scaled by breaking amplitude and depth. (AA) compare energy dissipation during the breaking process with results from the literature without storm surge.  >>️

They << conclude that a previously developed shallow-water inertial dissipation model for wave breaking on a uniform slope can be extended to this storm surge environment with good data collapse, and further discuss possibilities for a general parametrization of wave breaking valid across different depth regimes. >>️

Hunter Boswell, Guirong Yan, Wouter Mostert. Characterizing energy dissipation of shallow-water wave breaking in a storm surge. Phys. Rev. Fluids 8, 054801. May 5, 2023. 

https://journals.aps.org/prfluids/abstract/10.1103/PhysRevFluids.8.054801

Also: waves, soliton, drop, in https://www.inkgmr.net/kwrds.html

Keywords: gst, waves, soliton, drop 

# s-gst: about internal tides

<< In certain parts of the ocean, towering, slow-motion rollercoasters called internal tides trundle along for miles, rising and falling for hundreds of feet in the ocean's interior while making barely a ripple at the surface >>

<< Internal tides are generated in part by differences in water density, and created along continental shelf breaks, where a shallow seafloor suddenly drops off like a cliff, creating a setting where lighter water meets denser seas. In such regions, tides on the surface produce oscillating, vertical currents, which in turn generate waves below the surface, at the interface between warmer, shallow water , and colder, deeper water >>

<< Now for the first time [AA] have accurately simulated the motion of internal tides along a shelf break called the Middle Atlantic Bight ... >>

Jennifer  Chu. Researchers  find  explanation  for  interacting  giant, hidden  ocean  waves. Sept. 28,  2016.

http://phys.org/news/2016-09-explanation-interacting-giant-hidden-ocean.html

Samuel M. Kelly, Pierre F. J. Lermusiaux. Internal-tide interactions with the Gulf Stream and Middle Atlantic Bight shelfbreak front. Journal of Geophysical Research: Oceans. Volume 121, Issue 8 Aug. 2016 Pages 6271–6294 DOI:10.1002/2016JC011639

http://onlinelibrary.wiley.com/doi/10.1002/2016JC011639/abstract

# gst: the dance (swimming and sinking behavior) of pelagic snails

<< Swimming and sinking behavior by pelagic snails is poorly studied but is important in their ecology, predator-prey interactions, and vertical distributions. >>

AA << focused on how the shell shape, body geometry, and body size affect their swimming behavior from a fluid mechanics perspective. In addition, ZooScan image analysis and metabarcoding of archived vertically stratified MOCNESS samples were used to relate swimming behaviors to night time and daytime vertical distributions. While different large scale swimming patterns were observed, all species exhibited small scale sawtooth swimming trajectories caused by reciprocal appendage flapping. Thecosome swimming and sinking behavior corresponded strongly with shell morphology and size, with the tiny coiled shell pteropods swimming and sinking the slowest, the large globular shelled pteropods swimming and sinking the fastest, and the medium-sized elongated shell pteropods swimming and sinking at intermediate speeds. However, the coiled shell species had the highest normalized swimming and sinking speeds, reaching swimming speeds of up to 45 body lengths s–1. The sinking trajectories of the coiled and elongated shell pteropods were nearly vertical, but globular shell pteropods use their hydrofoil-like shell to glide downwards at approximately 20° from the vertical, thus retarding their sinking rate. The swimming Reynolds number (Re) increased from the coiled shell species [Re ∼ O(10)] to the elongated shell species [Re ∼ O(100)] and again for the globular shell species [Re ∼ O(1000)], suggesting that more recent lineages increased in size and altered shell morphology to access greater lift-to-drag ratios available at higher Re. Swimming speed does not correlate with the vertical extent of migration, emphasizing that other factors, likely including light, temperature, and predator and prey fields, influence this ecologically important trait. Size does play a role in structuring the vertical habitat, with larger individuals tending to live deeper in the water column, while within a species, larger individuals have deeper migrations. >>

Ferhat Karakas, Jordan Wingate, et al. Swimming and Sinking Behavior of Warm Water Pelagic Snails. Front. Mar. Sci. doi: 10.3389/ fmars.2020.556239. Sep 7, 2020. 

https://www.frontiersin.org/articles/10.3389/fmars.2020.556239/full    

<< And it's stunning to think that these sea butterflies are using the same fluid dynamics principles to fly through water that insects use to fly through air, >> David Murphy.

Poetry in motion: Engineers analyze the fluid physics of movement in marine snails. Frontiers. Sep 07, 2020

https://phys.org/news/2020-09-poetry-motion-fluid-physics-movement.html   

Also

<< Snails usually lumber along on their single fleshy foot; but not sea butterflies (Limacina helicina). These tiny marine molluscs gently flit around their Arctic water homes propelled by fleshy wings that protrude out of the shell opening. >>

These << snails swim using the same technique as flying insects, beating their wings in a figure-of-eight pattern,>>

Bizarre snail that swims like a flying insect. The Company of Biologists. Feb 17, 2016. 

https://phys.org/news/2016-02-bizarre-snail-insect.html   

David W. Murphy, Deepak Adhikari, et al. Underwater flight by the planktonic sea butterfly. Journal of Experimental Biology. 2016 219: 535-543. doi: 10.1242/jeb.129205. Feb 17, 2016.

https://jeb.biologists.org/content/219/4/535

# gst: apropos of breaking mechanisms, crack of a floating particle raft caused by waves.

<< When particles of a few tens of microns are spread on the surface of water, they aggregate under the action of capillary forces and form a thin floating membrane, a particle raft. >>

<< For a sufficiently strong wave amplitude, the raft breaks up progressively by developing cracks and producing fragments whose sizes decrease on a timescale long compared to the period of the wave. (AA)  characterize the breaking mechanisms.  >>️️

<< The visual appearance of the fragments distributed in size and surrounded by open water bears a notable resemblance to the floes produced by the fracturing of sea ice by waves in the polar oceans. Fragmentation concepts and morphological tools built for sea ice floes can be applied to (AA) macroscopic analog, on which the entire dynamic evolution is accessible. However, the mechanics of the two systems differ, as (AA) particle raft breaks due to the viscous stresses, whereas the sea ice fractures due to its bending by the waves. >>️

Louis Saddier, Ambre Palotai, et al. Breaking of a floating particle raft by water waves. Phys. Rev. Fluids 9, 094302. Sep 27, 2024.

https://journals.aps.org/prfluids/abstract/10.1103/PhysRevFluids.9.094302 

Also: 'crack', 'particle', in  https://www.inkgmr.net/kwrds.html 

Also: 'break' in  https://flashontrack.blogspot.com/search?q=break

Also: 'raft' in  https://flashontrack.blogspot.com/search?q=raft

Also: 'zattera' (quasi-stochastic poetry) in  https://inkpi.blogspot.com/search?q=zattera  'randa' (quasi-stochastic poetry) in https://inkpi.blogspot.com/search?q=randa

Keywords: gst, crack, break, particle, raft, particle raft

# gst: spontaneous bouncing, trampolining, and hovering behaviors of a levitating water droplet without constraints.

<< The levitating Leidenfrost (LF) state of a droplet on a heated substrate is often accompanied by fascinating behaviors such as star-shaped deformations, self-propulsion, bouncing, and trampolining. These behaviors arise due to the vapor flow instabilities at the liquid-vapor interface beneath the droplet at sizes typically comparable to the capillary length scale of the liquid. >>

AA << report on the spontaneous bouncing, trampolining, and hovering behavior of an unconstrained LF water droplet. (..) the water droplet exhibits an increase in bouncing height at specific radii with intermittent reduction in the height of bounce leading to a quiescent LF state. The reemergence of the trampolining behavior from the quiescent hovering state without any external forcing is observed at sizes as low as 0.1 times the capillary length. (AA) attribute the droplet bouncing behavior to the dynamics of vapor flow beneath the LF droplet. >>

AA << propose that the trampolining behavior of the droplet at specific radii is triggered by harmonic and subharmonic resonance between the natural frequency of the vapor layer and Rayleigh frequency of the droplet. This proposed mechanism of resonance-driven trampolining of LF droplets is observed to be applicable for different liquids irrespective of the initial volume and substrate temperatures, thus indicating a universality of the behavior. (AA) attribute the intermittent trampolining events to the change in the natural frequency of the droplet and the vapor layer due to evaporative mass loss. >>

Pranjal Agrawal, Susmita Dash. Reemergence of Trampolining in a Leidenfrost Droplet. arXiv: 2408.02335v1 [physics.flu-dyn]. Aug 5, 2024. 

https://arxiv.org/abs/2408.02335

Also: drop, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, drop, droplet, droploid, behav, behaviour

# gst: when and how a levitating droplet sings (as a pipe)

<< Sprinkle water onto a very hot pan, and you may notice that the droplets evaporate surprisingly slowly. They stick around because of what’s called the Leidenfrost effect—a thin layer of vapor forms between the droplets and the hot surface, insulating them from the heat, and keeping them from boiling off immediately. (..) droplets of water in this Leidenfrost regime emit periodic sounds, or beats.  >>️

<< While emitting sounds, the droplets oscillated as pulsing stars whose points moved radially in and out. (..) this vapor-layer frequency matched the period of the beats, and (AA) therefore concluded that vapor escaping from beneath the droplet was responsible for producing the periodic sounds. >>️

<< the frequency of the sounds made by a droplet depended on the droplet’s size—following the model of an organ pipe, whose tone depends on the velocity of sound and the length of the pipe. This implies that the sound production mechanism in a Leidenfrost droplet is similar to that of a wind instrument. >>

️

Erika K. Carlson. The Sounds of Levitating Water Droplets. Physics 13, s148. Nov 19, 2020.

https://physics.aps.org/articles/v13/s148

Tanu Singla,  Marco Rivera. Sounds of Leidenfrost drops. Phys. Rev. Fluids 5, 113604. doi: 10.1103/ PhysRevFluids.5.113604. Nov 19, 2020.

https://journals.aps.org/prfluids/abstract/10.1103/PhysRevFluids.5.113604

img     https://physics.aps.org/assets/73455c27-7d24-443b-a685-de931db74e09/e148_1.png

# gst: hidden complexity during the twinkle of a shrinking droplet

<< Captivating patterns found in the light scattered by an evaporating water droplet could be used to infer the properties of the droplet as it shrinks. >>

AA << collected the light that bounced off a spherical water droplet as the droplet shrunk, which happened naturally as it evaporated. The team observed twinkling patterns called Fano combs, which resemble the outlines of hedgehogs. >>

Ryan Wilkinson. Twinkling of a Shrinking Droplet Reveals Hidden Complexity. Physics 16, s9. Jan 24, 2023.

https://physics.aps.org/articles/v16/s9

AA << then fully explain it by expanding the quantum analogy. This turns the droplet into an “optical atom" with angular momentum, tunneling, and excited states. >>

Javier Tello Marmolejo, Adriana Canales, et al. Fano Combs in the Directional Mie Scattering of a Water Droplet. Phys. Rev. Lett. 130, 043804. Jan 24, 2023.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.130.043804

Also

keyword 'evaporation' in FonT

https://flashontrack.blogspot.com/search?q=evaporation

keyword 'drop' | 'droplet' | 'droploids' in FonT

https://flashontrack.blogspot.com/search?q=drop

https://flashontrack.blogspot.com/search?q=droplet

https://flashontrack.blogspot.com/search?q=droploids

keyword 'goccia' in Notes 

(quasi-stochastic poetry): 

https://inkpi.blogspot.com/search?q=goccia

Keywords: gst, drop, droplet, shrink, shrinking droplet, evaporation, transition

# astro: the turbulent history of Ryugu

<< The asteroid Ryugu may look like a solid piece of rock, but it's more accurate to liken it to an orbiting pile of rubble. >>

<< Ryugu is considered a C-type, or carbonaceous, asteroid, meaning it's primarily composed of rock that contains a lot of carbon and water (..) As expected, most of the surface boulders are also C-type; however, there are a large number of S-type, or siliceous, rocks as well. These are silicate-rich, lack water-rich minerals and are more often found in the inner, rather than outer, solar system. Given the presence of S- as well as C-type rocks on Ryugu, researchers are led to believe the little rubble-pile asteroid likely formed from the collision between a small S-type asteroid and Ryugu's larger C-type parent asteroid.  If the nature of this collision had been the other way around, the ratio of C- to S-type material in Ryugu would also be reversed. >>

Rock types on Ryugu provide clues to the asteroid's turbulent history. University of Tokyo. Sep 21, 2020. 

https://phys.org/news/2020-09-ryugu-clues-asteroid-turbulent-history.html

Tatsumi E., Sugimoto C., et al. Collisional history of Ryugu’s parent body from bright surface boulders. Nat Astron. doi: 10.1038/ s41550-020-1179-z. Sep 21, 2020.

https://www.nature.com/articles/s41550-020-1179-z   

Also

How small particles could reshape an asteroid. FonT. Sep 26, 2020.

https://flashontrack.blogspot.com/2020/09/gst-how-small-particles-could-reshape.html

# gst art: an image of chaotic hydrodynamics, by "Leo"

<< One of the first to visualize these flows was scientist, artist, and engineer Leonardo da Vinci, who combined keen observational skills with unparalleled artistic talent to catalog turbulent flow phenomena. Back in 1509, Leonardo was not merely drawing pictures. He was attempting to capture the essence of nature through systematic observation and description. In this figure,  https://cdn.arstechnica.net/wp-content/uploads/2018/10/daVinciWake.png   we see one of his studies of wake turbulence, the development of a region of chaotic flow as water streams past an obstacle. >>

Lee Phillips. Turbulence, the oldest unsolved problem in physics. The flow of water through a pipe is still in many ways an unsolved problem. Oct 10, 2018.

https://arstechnica.com/science/2018/10/turbulence-the-oldest-unsolved-problem-in-physics/

# gst: fingerprints of reality: water drops that vibrate, flames that oscillate, and viscous fluids that form rivulets ...

<< In one of this year’s three winning videos, a drop of blue-dyed water at the bottom of an anise-oil and alcohol mixture begins to grow and shake, eventually pinching off a fragment that floats up. The process repeats several times. Created by now four-time Gallery-of-Fluid-Motion winner Oscar Enríquez of Carlos III University of Madrid and his colleagues, the visuals are accompanied by a soundtrack featuring a musical improvisation by a trio consisting of Enríquez on percussion, a violinist, and a clarinetist. Each instrument in the trio represents one of the three fluids. >>

Award-Winning Fluid Videos. APS. Physics 11, 121. Nov 21, 2018.

https://physics.aps.org/articles/v11/121

# gst: breakup of Janus droplet in a bifurcating microchannel

<< Droplet breakup is frequently observed in natural and industrial processes (..)  Although valuable insights on the breakup mechanisms of single-phase droplets in microchannels have been provided over the past decades, the breakup physics of complex emulsions is still poorly understood. >>️

<< Spatially asymmetric Janus microdroplets, distinct from single-phase or double emulsion droplets possessing one uniform interface with the ambient phase, are anticipated to show unique breakup behaviors, which has not been explored.  >>️

AA << conduct both microfluidic experiments and three-dimensional lattice Boltzmann simulations to investigate the dynamic breakup of ionic liquid (IL)-water Janus droplets in an assembled 3D-printed microchannel with a bifurcation. >>️

<< Three different flow regimes are identified: (i) division into two daughter Janus droplets, (ii) breakup into a single-phase droplet and a smaller Janus droplet, and (iii) nonbreakup.  >>️

AA << find that the strong constraint effect of the main channel and large Ca_av (average capillary numbers) values are essential to the symmetrical breakup of Janus droplets. The tunnel between the mother droplet and the wall of the main channel, which allows the lateral shift of the Janus droplet, and moderate flow rates facilitate the breakup of the IL single-phase portion of Janus droplets.  >>

<< Through 90° rotation of the splitting microchannel, (AA) elucidate the distinctions in Janus droplet behaviors under two baffle orientations. Potential impacts of the oblique flow characteristic of [bmim]⁢Fe⁢Cl4-water Janus droplets on the droplet breakup are discussed. >>️

️

Hao Wang, Shiteng Wang, et al. Dynamic breakup of Janus droplet in a bifurcating microchannel. Phys. Rev. Fluids 9, 064203. Jun 11, 2024. 

https://journals.aps.org/prfluids/abstract/10.1103/PhysRevFluids.9.064203 

Also: 'Janus' in FonT https://flashontrack.blogspot.com/search?q=janus

Also: 'drop', 'droplet', 'droploid', in https://www.inkgmr.net/kwrds.html 

Keywords: gst, Janus, drop, droplet, droploid

# life: the 'built-in float' of an ancient marine predator

<< About 240 million years ago, when reptiles ruled the ocean, a small lizard-like predator floated near the bottom of the edges in shallow water, picking off prey with fang-like teeth. >>

<< Our analysis of two well-preserved skeletons reveals a reptile with a broad, pachyostotic body (denser boned) and a very short, flattened tail. A long tail can be used to flick through the water, generating thrust, but the new species we've identified was probably better suited to hanging out near the bottom in shallow sea, using its short, flattened tail for balance, like an underwater float, allowing it to preserve energy while searching for prey, >> Qing-Hua Shang.

<< Perhaps this small, slow-swimming marine reptile had to be vigilante for large predators as it floated in the shallows, as well as being a predator itself, >> Xiao-Chun Wu.

Taylor & Francis. Ancient marine predator had a built-in float. Oct 28, 2020. 

https://phys.org/news/2020-10-ancient-marine-predator-built-in.html

Qing-Hua Shang, Xiao-Chun Wu, Chun Li. A New Ladinian Nothosauroid (Sauropterygia) from Fuyuan, Yunnan Province, China. Journal of Vertebrate Paleontology. doi: 10.1080/ 02724634.2020.1789651. Oct 29, 2020.

https://www.tandfonline.com/doi/10.1080/02724634.2020.1789651  

# gst: even a single bubble can produce creative musical outcomes

<< Producing original and arranging existing musical outcomes is an art that takes years of learning and practice to master. Yet, despite the constant advances in the field of AI-powered musical creativity, production of quality musical outcomes remains a prerogative of the humans. Here we demonstrate that a single bubble in water can be used to produce creative musical outcomes, when it nonlinearly oscillates under an acoustic pressure signal that encodes a piece of classical music. >>️

Ivan S. Maksymov. Musical creativity enabled by nonlinear oscillations of a bubble in water. arXiv:2304.00822v1 [cs.SD]. Apr 3, 2023. 

https://arxiv.org/abs/2304.00822

keyword "bubble" in FonT

https://flashontrack.blogspot.com/search?q=bubble

Keywords: gst, ai, fluid dynamics, bubble, sound, music, audio processing

# gst: when a soliton juggles ('catches' and 'throws') droplets

<< Jugglers normally work with solid objects, but a research team has now demonstrated a system that juggles liquid drops. (AA)  have previously shown that liquid drops can bounce in place above the surface of the same liquid—or bounce while moving across the surface—if the container is continuously vibrated (..) In these past experiments, the surface was nearly flat, except for waves generated by the bouncing drop. In the new work by undergraduate student Camila Sandivari of the University of Chile and her colleagues, the vibrations cause the liquid surface to form a large standing wave that actively “catches” and “throws” the drop during each cycle of its oscillation. The trapping of the drop is similar in principle to other types of wave traps, such as laser-based optical tweezers, and the system could potentially lead to new types of traps for larger objects. >>

AA << placed water mixed with a dye and a surface-tension-reducing agent in a 20-cm-long, 2.6-cm-wide basin that supports an unusual type of surface wave when the basin is vibrated in a specific frequency range. In this wave, rather than a series of oscillating peaks and valleys, there is only a single standing wave peak, called a soliton. However, this peak doesn’t oscillate uniformly across the basin’s short dimension (the width). A peak appears at one of the long walls coincident with a valley at the opposite wall, and then the peak and the valley switch places moments later, keeping a relatively flat “node” line along the central long axis of the basin. >>

AA << used a pipette to place a few-millimeter-wide drop of the same fluid just above the oscillating soliton, close to one of the long walls, and found that drops could be juggled for up to 90 minutes. The team attributes this unusual stability in part to a property of the soliton: if the drop wanders off-center, the oscillating surface wave pulls it back toward its center, similar to the way the laser field in optical tweezers is able to stably hold a small particle at its center. >>

David Ehrenstein. Juggling Water Drops. Physics 16, 21. Feb 10, 2023. 

https://physics.aps.org/articles/v16/21

Also

keyword 'drop' | 'droplet' | 'droploids' in FonT

https://flashontrack.blogspot.com/search?q=drop

https://flashontrack.blogspot.com/search?q=droplet

https://flashontrack.blogspot.com/search?q=droploids

keyword 'goccia' in Notes 

(quasi-stochastic poetry)

https://inkpi.blogspot.com/search?q=goccia

keyword 'solitons' in FonT

https://flashontrack.blogspot.com/search?q=soliton

https://flashontrack.blogspot.com/search?q=solitons

Keywords: gst, solitons, drop, droplet, droploids, goccia