# evol: the rare art of surviving: the case of Actinopterygians ray-finned fishes

<< Actinopterygians (ray-finned fishes) successfully passed through four of the big five mass extinction events of the Phanerozoic >>

<< Many researchers have assumed that the Permo-Triassic mass extinction (..) and end-Triassic extinction (..) had little impact on actinopterygians, despite devastating many other groups. >>

Fiann M. Smithwick, Thomas L. Stubbs. Phanerozoic survivors: Actinopterygian evolution through the Permo-Triassic and Triassic-Jurassic mass extinction events.  Evolution. 2018; 72 (2): 348 - 62. doi: 10.1111/evo.13421. Feb 2, 2018

http://onlinelibrary.wiley.com/doi/10.1111/evo.13421/abstract

University of Bristol. The resilience of ray-finned fishes. Feb 5, 2018.

https://m.phys.org/news/2018-02-resilience-ray-finned-fishes.html 

# web: about ghostly followers: the real Jessica

<< The real Jessica [..] is a Minnesota teenager with a broad smile and wavy hair. [..] But on Twitter, there is a version of Jessica that none of her friends or family would recognize. >>

<< The accounts that most resemble real people [..] reveal a kind of large-scale social identity theft. At least 55,000 of the accounts use the names, profile pictures, hometowns and other personal details of real Twitter users, including minors, according to a Times data analysis. >>

<< By some calculations, as many as 48 million of Twitter’s reported active users - nearly 15 percent - are automated accounts designed to simulate real people, though the company claims that number is far lower. >>

Nicholas Confessore, Gabriel JX  Dance, Richard Harris, Mark Hansen.  The Follower Factory. Jan 27, 2018.

https://www.nytimes.com/interactive/2018/01/27/technology/social-media-bots.html

<< A big chunk of those "likes," "retweets," and "followers" lighting up your Twitter account may not be coming from human hands. According to new research from the University of Southern California and Indiana University, up to 15 percent of Twitter accounts are in fact bots rather than people. >>

Michael Newberg. As many as 48 million Twitter accounts aren't people, says study. March 10, 2017.

https://www.cnbc.com/2017/03/10/nearly-48-million-twitter-accounts-could-be-bots-says-study.html

Onur Varol, Emilio Ferrara, et a. Online Human-Bot Interactions: Detection, Estimation, and Characterization. arXiv: 1703.03107.v2 Mar 27, 2017.

https://arxiv.org/pdf/1703.03107.pdf

Allie Nicodemo. Why buy social bots? For 'illusion of popularity,' researcher says. Jan 30, 2018

https://m.phys.org/news/2018-01-social-bots-illusion-popularity.html

# ecol: first census of Zanzibar Red Colobus monkey

AA << present the first systematic assessment of the population, demography and distribution of the Endangered Zanzibar red colobus Piliocolobus kirkii, in Unguja in the Zanzibar archipelago >>

AA << estimate the total population comprises 5,862 individuals in 342 groups (mean group size 17.12); 3.4 times the mean of all previous estimates >>

<< The results indicate that P. kirkii is resilient and thriving far better than assumed >>

Tim RB Davenport, Said A Fakih, et al.  Zanzibar's  endemic red colobus Piliocolobus kirkii: first systematic  and total assessment  of population, demography and distribution. Oryx, 1-9. doi: org/10.1017/S003060531700148X. Dec 07, 2017

https://www.cambridge.org/core/journals/oryx/article/zanzibars-endemic-red-colobus-piliocolobus-kirkii-first-systematic-and-total-assessment-of-population-demography-and-distribution/F084062464F9C99208E5F7E8CB155880

Wildlife Conservation Society. Hope for one of the world's rarest primates: First census of Zanzibar Red Colobus monkey. Dec 14, 2017.

https://m.phys.org/news/2017-12-world-rarest-primates-census-zanzibar.html

# gene: inducing pluripotent stem cells from mice skin cells using CRISPR tech.

<< In a scientific first, researchers at the Gladstone Institutes turned skin cells from mice into stem cells by activating a specific gene in the cells using CRISPR technology. The innovative approach offers a potentially simpler technique to produce the valuable cell type and provides important insights into the cellular reprogramming process. >>

Gladstone Institutes. Researchers create first stem cells using CRISPR genome activation. Jan 18, 2018.

https://m.phys.org/news/2018-01-stem-cells-crispr-genome.html

AA << study generated authentic iPSCs [induced pluripotent stem cells] with CRISPR activation through precise epigenetic remodeling of endogenous loci and shed light on how targeted chromatin remodeling triggers pluripotency induction. >>

Peng Liu, Meng Chen, et al. CRISPR-Based Chromatin Remodeling of the Endogenous Oct4 or Sox2 Locus Enables Reprogramming to Pluripotency. Cell Stem Cell. 2018; 22 (2): 252 - 61.e4

http://www.cell.com/cell-stem-cell/fulltext/S1934-5909(17)30501-5

# gst: an intriguing model of pulsating dissolution

<< The reaction of crystalline material with fluids is of relevance for natural and technical processes. A basic assumption has been that the reaction products are continuously released from the crystal surface. New experimental and analytical results show something fundamentally different: Material is released in a series of reaction pulses. >>

Cornelius Fischer, Andreas Luttge. Pulsating dissolution of crystalline matter. PNAS 2018; 115 (5) 897-902. doi: 10.1073/pnas.1711254115. Jan 30, 2018.

http://www.pnas.org/content/115/5/897

Helmholtz Association of German Research Centres. Study: Pulsating dissolution found in crystals. Jan 17, 2018.

https://m.phys.org/news/2018-01-pulsating-dissolution-crystals.html

# brain: self-evaluation of one's own ignorance

<< Self-evaluation of one's own ignorance requires us to peer into our own mind retrospectively. [AA] found that only the bilateral frontopolar cortices (area 10) are recruited for metacognitive evaluation of non-experienced events in macaque monkeys performing metacognitive confidence judgment on memory >>

Kentaro Miyamoto, Rieko Setsuie, et al. Reversible Silencing of the Frontopolar Cortex Selectively Impairs Metacognitive Judgment on Non-experience in Primates.
Neuron. doi: 10.1016/j.neuron. 2017.12.040. Jan 25, 2018.

http://www.cell.com/neuron/fulltext/S0896-6273(17)31208-4

Cognitive Neuroscience and the Awareness of Ignorance. Jan 27, 2018.

https://neurosciencenews.com/ignorance-awareness-8383

# chem: extreme superconductive in random atomic-scale mixture

<< High-entropy alloys (HEAs) are a new class of materials that are composed of multiple transition-metal elements in equimolar or near-equimolar ratios >>

<< many HEAs have been found in disordered solid-solution phases with body-centered-cubic, hexagonal closest-packed, and face-centered-cubic crystal structures >>

<< In many respects, HEAs display novel properties, including ultrahigh fracture toughness at cryogenic temperatures, excellent specific strength, and superior mechanical performance at high temperatures. In addition to their promising mechanical properties, some HEAs also exhibit interesting electronic properties: [TaNb]1−x(ZrHfTi)x HEAs were found to display superconductivity, for example >>

AA << report high-pressure studies on the superconducting HEA (TaNb)0.67(HfZrTi)0.33, [..] this alloy exhibits extraordinarily robust superconductivity - its zero-resistance superconducting state is still achieved even at a pressure of 190.6 GPa, or almost 2 megabars (1 Mbar = 1011 pascal), a pressure like that within the outer core of the earth. >>

Jing Guo, Honghong Wang, et al.  Robust zero resistance in a superconducting high-entropy alloy at pressures up to 190 GPa. PNAS 2017; 114 (50) 13144-7.  doi: 10.1073/pnas.1716981114.

http://www.pnas.org/content/114/50/13144

Laura Mgrdichian. A material that superconducts continuously up to extreme pressures.  Jan 17, 2018

https://m.phys.org/news/2018-01-material-superconducts-extreme-pressures.html