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venerdì 18 maggio 2018

# astro: crazy chaotic encounters (and megamerger)

<< Binary black holes are basically like giant targets hanging out in the cluster, and as you throw other black holes or stars at them, they undergo these crazy chaotic encounters >>

<< What people had done in the past was to treat this as a purely Newtonian problem, (..)  Newton’s theory of gravity works in 99.9 percent of all cases. The few cases in which it doesn’t work might be when you have two black holes whizzing by each other very closely, which normally doesn’t happen in most galaxies >> Carl Rodriguez

Jennifer Chu. Dense stellar clusters may foster black hole megamergers. MIT News Office. Apr 10, 2018.

http://news.mit.edu/2018/dense-stellar-clusters-may-foster-black-hole-megamergers-0410

Carl L. Rodriguez, Pau Amaro-Seoane, et al. Post-Newtonian Dynamics in Dense Star Clusters: Highly-Eccentric, Highly-Spinning, and Repeated Binary Black Hole Mergers.

Phys. Rev. Lett. 120, 151101 (2018). doi: 10.1103/PhysRevLett.120.151101.

arXiv:1712.04937 [astro-ph.HE]. Mar 14, 2018

https://arxiv.org/abs/1712.04937

mercoledì 16 maggio 2018

# astro: a theoretical model of the final game: it will turn into gas and dust

AA << predict [the Sun] will turn into a massive ring of luminous, interstellar gas and dust, known as a planetary nebula >>

<< This is a nice result. Not only do we now have a way to measure the presence of stars of ages a few billion years in distant galaxies, which is a range that is remarkably difficult to measure, we even have found out what the sun will do when it dies! >> Albert Zijlstra

University of Manchester. What will happen when our sun dies? May 7, 2018.

https://m.phys.org/news/2018-05-sun-dies.html

K. Gesicki, A. A. Zijlstra & M. M. Miller Bertolami. The mysterious age invariance of the planetary nebula luminosity function bright cut-off. Nature Astronomy. doi: 10.1038/s41550-018-0453-9. May 07, 2018.

https://www.nature.com/articles/s41550-018-0453-9

martedì 15 maggio 2018

# brain: creativity, neural patterns involved in Jazz improvisation

<< "I had always intuitively understood that the creative process in jazz improvisation is very different than the process of memorization," he (Charles Limb) explained. "That is immediately apparent when you play" >>

<< While the musicians improvised, the parts of the brain that allow humans to express ourselves - the medial prefrontal cortex or "default network" - became more active. At the same time, the part of the brain responsible for self-inhibition and control, the dorsolateral prefrontal cortex, became dormant. >>

<< By inhibiting the part of the brain that allows self-criticism, the musicians were able to stay in their creative flow, known as "in the zone." >>

Sandee LaMotte, CNN. Jazz improv and your brain: The key to creativity?  Apr 29, 2018.

https://edition-m.cnn.com/2018/04/29/health/brain-on-jazz-improvisation-improv/index.html

Charles J. Limb, Allen R. Braun. Neural Substrates of Spontaneous Musical Performance: An fMRI Study of Jazz Improvisation.  PLOS ONE 3(2): e1679.  doi: 10.1371/journal.pone.0001679. Feb 27, 2008.

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0001679  

Also

# brain: about creativity in musical improvisation.  Apr 6, 2018.

https://flashontrack.blogspot.it/2018/04/brain-about-creativity-in-musical.html

2117 - la destra e la sinistra di Hines.
Feb 02, 2007.

https://inkpi.blogspot.it/2007/02/2117-la-destra-e-la-sinistra-di-hines.html


lunedì 14 maggio 2018

# behav: individual warning recognition among Jackdaws

<< Jackdaws recognise each other's voices and respond in greater numbers to warnings from familiar birds than strangers >>

AA << have discovered that each bird has a unique call, and the size of the mob depends on which bird calls the warning >>

University of Exeter. Angry birds: Size of jackdaw mobs depends on who calls warning. May 10, 2018.

https://m.phys.org/news/2018-05-angry-birds-size-jackdaw-mobs.html

<< (..) so the identity of the initiator may determine the magnitude of the group response >>

Richard D. Woods, Michael Kings, et al. Caller characteristics influence recruitment to collective anti-predator events in jackdaws. Scientific Reports.  8 : 7343 (2018). doi: 10.1038/s41598-018-25793-y

https://www.nature.com/articles/s41598-018-25793-y

FonT

quindi le taccole discriminano   l'individuo che lancia l'allarme, come per dare "un peso" alla veridicita' del segnale; se le taccole hanno una sorta di approccio analitico per la gestione del rumore legato al messaggio, significa che sanno gestire le "fake news" ... come gli umani, anzicheforse ...

sabato 12 maggio 2018

# brain: exploring a cold-blooded reptile using functional MRI: crocodiles listen to classical music

AA << exposed the animals to various visual and auditory stimuli, including classical music by Johann Sebastian Bach. At the same time, they measured the animals' brain activity. The results have shown that additional brain areas are activated during exposure to complex stimuli such as classical music - as opposed to exposure to simple sounds. The processing patterns strongly resemble the patterns identified in mammals and birds in similar studies >>

Ruhr-Universitaet-Bochum. Crocodiles listen to classical music in MRI scanner. May 3, 2018

https://m.phys.org/news/2018-05-crocodiles-classical-music-mri-scanner.html

Mehdi Behroozi, Brendon K. Billings, et al. Functional MRI in the Nile crocodile: a new avenue for evolutionary neurobiology. Proc Royal Soc B Biol Sci. doi: 10.1098/rspb.2018.0178. Apr 25, 2018.

http://rspb.royalsocietypublishing.org/content/285/1877/20180178.article-info

venerdì 11 maggio 2018

# gst: the dance of complex knots (in DNA), from mobile to jammed states

AA << show for the first time experimentally that knots can go from a mobile to a jammed state by varying an applied strain rate, and that this jamming is reversible >>

Alexander R. Klotz, Beatrice W. Soh, and Patrick S. Doyle. Motion of Knots in DNA Stretched by Elongational Fields.  Phys. Rev. Lett. 120, 188003. May 3, 2018.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.120.188003

Anne Trafton. Chemical engineers discover how to control knots that form in DNA molecules. Massachusetts Institute of Technology. May 3, 2018.

https://m.phys.org/news/2018-05-chemical-dna-molecules.html

giovedì 10 maggio 2018

# behav: group’s dominance hierarchy seems statistically non-linear (among chimps)

<< Through agonistic networks, [AA] found that group members reciprocally exhibited agonism, and the group’s dominance hierarchy was statistically non-linear. One chimpanzee emerged as the most dominant through agonism but was least connected to other group members across affiliative networks.  [AA] results indicate that the conventional methods used to calculate individuals' dominance rank may be inadequate to wholly depict a group's social relationships in captive sanctuary populations >>

Jake A. Funkhouser, Jessica A. Mayhew, John B. Mulcahy. Social network and dominance hierarchy analyses at Chimpanzee Sanctuary Northwest. PLoS One. 2018 Feb 14; 13(2):e0191898. doi: 10.1371/journal.pone.0191898. eCollection 2018.

https://www.ncbi.nlm.nih.gov/pubmed/29444112 

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0191898