# gst astro: when a superbubble can generate trains of shock waves

<< Sixty-seven million light-years away, a galaxy is blowing enormous bubbles. We know what they are. Known as nuclear superbubbles, the structures are likely created by the supermassive black hole in the galaxy's centre. Now, thanks to new data, we know something incredible is occurring inside them. >>

<< Observations from NASA's Chandra X-ray Observatory of spiral galaxy NGC 3079 have revealed that the bubbles are actually a huge cosmic particle accelerator, producing energetic high-speed particles around their edges.  >>

<< As the bubbles expand into the surrounding gas of the interstellar medium, they generate shock waves, which in turn produce tangled magnetic fields. (..)  particles ricochet around these shock magnetic fields; when they pass through the shock front, they get an acceleration boost.  >>

Michelle Starr. Astronomers Have Found 'Superbubbles' Producing Shock Waves in Another Galaxy.  Mar 4, 2019.

https://www.sciencealert.com/colossal-bubbles-blown-by-a-supermassive-black-hole-are-a-cosmic-particle-accelerator

Jiang-Tao Li, Edmund Hodges-Kluck, et al. Detection of non-thermal hard X-ray emission from the "Fermi bubble" in an external galaxy.  ApJ in press. arXiv:1901.10536v1 [astro-ph.HE] Jan 31, 2019.

https://arxiv.org/abs/1901.10536

# astro: quiescent black holes abound in our Galaxy

AA << results provide new circumstantial evidences for a wandering intermediate-mass black hole in the Galactic center, suggesting also that high-velocity compact clouds can be probes of quiescent black holes abound in our Galaxy. >>

Shunya Takekawa, Tomoharu Oka, et al.  Indication of Another Intermediate - mass Black Hole in the Galactic Center. arXiv: 1812.10733v1 [astro-ph.GA]  doi: 10.3847/2041-8213/aafb07

https://arxiv.org/abs/1812.10733

"The Invisible Galaxy" - 100 Million Black Holes Lurking in the Milky Way (Weekend Feature). Mar 2, 2019

https://dailygalaxy.com/2019/03/the-invisible-galaxy-100-million-black-holes-lurking-in-the-milky-way-weekend-feature/

# gst phyto: an evidence for alternative transient states

AA << have discovered that plant communities follow different trajectories when they adapt to dryer conditions than when they adapt to more frequently flooded conditions. Further, in two side studies in the same experiment they found that flooding history of the vegetation alter the response of germinating seeds and of litter decomposition to the current conditions. >>

<< This is one of the most direct experimental evidence to date for alternative transient states, >> Judith Sarneel.

Plant communities do not take the same route from A to B as from B to A. Umea University. Feb 25, 2019.

https://m.phys.org/news/2019-02-route.html

Judith M. Sarneel  Maria Dolores Bejarano, et al. Local flooding history affects plant recruitment in riparian zones. Journal of Vegetation Science.
doi: 10.1111/jvs.12731 Feb 3, 2019

https://onlinelibrary.wiley.com/doi/abs/10.1111/jvs.12731

# behav: familiarity vs. aggression (among the fish Poecilia formosa)

<< Contrary to our predictions, fish that were the most familiar with each other showed the highest levels of aggression. Additionally, fish that were less familiar with each other exhibited the highest group cohesion and took the longest to begin feeding, compared to the more familiar fish. >>

Carolina Doran, David Bierbach, Kate L. Laskowski.  Familiarity increases aggressiveness among clonal fish. Animal Behaviour. Volume 148, February 2019, Pages 153-159. doi: 10.1016/j.anbehav.2018.12.013

https://www.sciencedirect.com/science/article/pii/S0003347218303725?via%3Dihub

Fish with a high level of familiarity are more aggressive towards each other. Forschungsverbund Berlin e.V. (FVB). Feb 19, 2019

https://m.phys.org/news/2019-02-fish-high-familiarity-aggressive.html

# acad aibot: the real success (also) in scientific research: the automatic search for deviations ...

<< Imagine that you have a lot of data, but you do not really know what you are looking for. So what do you do? In that case you use a computer that automatically searches for deviations. >>

Search engine for new breakthroughs in physics. Radboud University.  Feb 19, 2019

https://m.phys.org/news/2019-02-breakthroughs-physics.html

M. Aaboud, G. Aad, et al. A strategy for a general search for new phenomena using data-derived signal regions and its application within the ATLAS experiment. The European Physical Journal C (2019). doi: 10.1140/epjc/s10052-019-6540-y

https://link.springer.com/article/10.1140%2Fepjc%2Fs10052-019-6540-y

# gst: apropos chaotic cooperation

<< Ecological theory has demonstrated that when direct, pairwise interactions among a group of species are too numerous, or too strong, then the coexistence of these species will be unstable to any slight perturbation. >>

Stacey Butler & James P. O’Dwyer.
Stability criteria for complex microbial communities. Nature Communications Volume 9, Article number: 2970 (2018)

https://www.nature.com/articles/s41467-018-05308-z

https://www.biorxiv.org/content/10.1101/293605v2

<< Pairs of organisms that live off each other sometimes do so well in the mathematical simulations - thriving exponentially in extreme cases, in what Robert May, the theoretical ecology pioneer, once called "an orgy of mutual benefaction" — that everything else can go extinct. >>

AA << explored more precisely how the give-and-take in mutualism affects ecosystem stability and how, under the right conditions, it might contribute to it.  >>

Veronique Greenwood. How Nature Defies Math in Keeping Ecosystems Stable. Sep 26, 2018.

https://www.quantamagazine.org/how-nature-defies-math-in-keeping-ecosystems-stable-20180926/

https://twitter.com/QuantaMagazine/status/1099390696455323651

# soc: a study about income: more than 63% of American children live in "asset" poverty

<< More than 63 percent of American children and 55 percent of Americans live in "asset" poverty, meaning they have few or no assets to rely on in the event of a financial shock such as a job loss, a medical crisis or the recent federal government shutdown, >>

Michelle Klampe. Nearly two-thirds of American children live in asset poverty, new study shows. Oregon State University.  Feb 21, 2019.

https://m.phys.org/news/2019-02-two-thirds-american-children-asset-poverty.html

David W. Rothwell,  Timothy Ottusch, Jennifer K. Finders. Asset poverty among children: A cross-national study of poverty risk. Children and Youth Services Review. Volume 96, January 2019, Pages 409-19. doi: 10.1016/j.childyouth.2018.11.045. Nov 23, 2018.

https://www.sciencedirect.com/science/article/pii/S0190740918305759?via%3Dihub