# gst: sand dunes 'communication' via turbulent swirls

<< Even though they are inanimate objects, sand dunes can 'communicate' with each other. A team (..) has found that as they move, sand dunes interact with and repel their downstream neighbours. Using an experimental dune 'racetrack', (they) observed that two identical dunes start out close together, but over time they get further and further apart. This interaction is controlled by turbulent swirls from the upstream dune, which push the downstream dune away.  >>

Sand dunes can 'communicate' with each other. University of Cambridge. 

 Feb 4, 2020.

https://m.phys.org/news/2020-02-sand-dunes.html

Karol A. Bacik, Sean Lovett, et al. Wake Induced Long Range Repulsion of Aqueous Dunes. Phys. Rev. Lett. 124, 054501. Feb 4, 2020.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.124.054501

Also

keyword 'sand' in Notes

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

# 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

# gst: tiny deviations (inside a phase transition) to avoid a near-complete annihilation.

<< Recently discovered ripples of spacetime called gravitational waves could contain evidence to prove the theory that life survived the Big Bang because of a phase transition that allowed neutrino particles to reshuffle matter and anti-matter, >>

<< According to the Big Bang theory of modern cosmology, matter was created with an equal amount of anti-matter. If it had stayed that way, matter and anti-matter should have eventually met and annihilated one to one, leading up to a complete annihilation.

But our existence contradicts this theory. To overcome a complete annihilation, the Universe must have turned a small amount of anti-matter into matter creating an imbalance between them. >>  

<< the Universe went through a phase transition so that neutrinos could reshuffle matter and anti-matter. >>

Showing how the tiniest particles in our Universe saved us from complete annihilation. Kavli Institute for the Physics and Mathematics of the Universe. Feb 3, 2020.

https://m.phys.org/news/2020-02-tiniest-particles-universe-annihilation.html

Jeff A. Dror, Takashi Hiramatsu, et al.  Testing the Seesaw Mechanism and Leptogenesis with Gravitational Waves.  Phys. Rev. Lett. 124, 041804. doi: 10.1103/PhysRevLett.124.041804. Jan 28, 2020. 

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.124.041804

# life: ancient Siberian hunters used hot pots to survive the ice age

<< A new study shows that ancient Siberian hunters created heat resistant pots so that they could cook hot meals - surviving the harshest seasons of the ice age by extracting nutritious bone grease and marrow from meat. >>

Hot pots helped ancient Siberian hunters survive the Ice Age. University of York. Feb 1, 2020.

 

https://m.phys.org/news/2020-02-hot-pots-ancient-siberian-hunters.html

<< regional differences in pottery use also map onto contrasting manufacturing techniques, with vessels from the Middle and from the Lower Amur forming distinct pottery-making traditions. These combined insights appear to indicate a greater degree of variability in the development and use of early pottery in East Asia than has hitherto been indicated. >>

Shinya Shoda, Alexandre Lucquin, et al. Late Glacial hunter-gatherer pottery in the Russian Far East: Indications of diversity in origins and use. Quaternary Science Reviews. Volume 229, 1 February 2020, 106124. doi: 10.1016/j.quascirev.2019.106124.

https://www.sciencedirect.com/science/article/abs/pii/S0277379119305013

Also (in FonT)

keyword 'nomads'

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

keyword 'hunter-gatherer'

https://flashontrack.blogspot.com/search?q=hunter-gatherer

# life: a normal (fuzzy, bizarre) Nature jumping, the little carrier snake that can bite a world ...

<<  Reports indicate that snakes were sold in the local seafood market in Wuhan, raising the possibility that the 2019-nCoV might have jumped from the host species - bats - to snakes and then to humans at the beginning of this coronavirus outbreak. However, how the virus could adapt to both the cold-blooded and warm-blooded hosts remains a mystery. >>

Haitao Guo, Guangxiang “George” Luo, Shou-Jiang Gao. Snakes could be the original source of the new coronavirus outbreak in China. Jan 22, 2020.

https://theconversation.com/snakes-could-be-the-original-source-of-the-new-coronavirus-outbreak-in-china-130364

Wei Ji, Wei Wang, et al. Homologous recombination within the spike glycoprotein of the newly identified coronavirus may boost cross‐species transmission from snake to human. Journal of Medical Virology. doi: 10.1002/jmv.25682. Jan 22, 2020.

https://onlinelibrary.wiley.com/doi/abs/10.1002/jmv.25682

Also

here a Brazilian 'relative' of the Chinese snake ...

# life: squeezing jaraca' (Bothrops jararaca). FonT. Dec 24, 2019. 

https://twitter.com/flashontrack/status/1209527656091402243

https://flashontrack.blogspot.com/2019/12/life-squeezing-jaraca-bothrops-jararaca.html

# phys: nature does not always respect symmetry, the hypothesis

<< Physicists have been looking for laws that explain both the microscopic world of elementary particles and the macroscopic world of the universe and the Big Bang at its beginning, expecting that such fundamental laws should have symmetry in all circumstances. However, last year, two physicists found a theoretical proof that, at the most fundamental level, nature does not respect symmetry. >>

<< To try to understand gravity on the quantum level, Hirosi Ooguri, (..) and Daniel Harlow, (..) started with the holographic principle. This principle explains three-dimensional phenomena influenced by gravity on a two-dimensional flat space that is not influenced by gravity.  >>

<< The researchers showed that symmetry only affects the shaded regions in the diagram, not around the spot in the middle, thus there cannot be global symmetry.  >>

Motoko Kakubayashi. Gravity: We might have been getting it wrong this whole time. Kavli Institute for the Physics and Mathematics of the Universe. Jan 24, 2020.

https://m.phys.org/news/2020-01-gravity-wrong.html

Daniel Harlow, Hirosi Ooguri. Constraints on Symmetries from Holography. Phys. Rev. Lett. 122, 191601. doi: 10.1103/ PhysRevLett.122.191601. May 17, 2019.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.122.191601

Daniel Harlow, Hirosi Ooguri. Symmetries in quantum field theory and quantum gravity. arXiv: 1810.05338v2 [hep-th]. Jun 6, 2019.

https://arxiv.org/abs/1810.05338

# gst: self‐assembly of porous, chiral nano-patterns from simple building blocks.

<< Using a simple rod-like building block with hydroxamic acids at both ends scientists (..) created self- assembling porous, chiral nano structures.  >>

<< Like our left and right hands, the shape of two mirrored cage structures cannot be superimposed. Since the 19th century, academics have characterized this type of object symmetry as 'chiral,' from the ancient Greek meaning 'hand.' These kinds of molecules are frequently found in natural compounds. Chirality influences interactions of polarized light and magnetic properties and plays a vital role in life.  For example, our olfactory receptors react very differently to the two mirror images of the limonene molecule: one smells like lemon, the other like pine. This so-called chiral recognition is a process that can determine whether a molecule acts as medicine or poison. >>

Complex, porous, chiral nano-patterns arise from a simple linear building blocks. Technical University Munich. Jan 16, 2020.

https://m.phys.org/news/2020-01-complex-porous-chiral-nano-patterns-simple.html

<< Regrettably (in this specific experimental context), the end groups proved to be elusive >>

Chao Jing,  Bodong Zhang, et al. Snapshots of Dynamic Adaptation: Two‐Dimensional Molecular Architectonics with Linear Bis‐Hydroxamic Acid Modules. Angewandte Chemie International Edition. Volume 58, Issue 52. doi: 10.1002/anie.201912247. Oct 31, 2019. 

https://onlinelibrary.wiley.com/doi/full/10.1002/anie.201912247

Also

keyword 'chiral' in FonT

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