lunedì 19 marzo 2018

# evol: the early bird Archaeopteryx was an incidental, short-distance, active flyer

<< The wing bones of Archaeopteryx were shaped for incidental active flight, but not for the advanced style of flying mastered by today's birds >>

European Synchrotron Radiation Facility. The early bird got to fly: Archaeopteryx was an active flyer. Mar 13, 2018.

AA << analyses reveal that the architecture of Archaeopteryx's wing bones consistently exhibits a combination of cross-sectional geometric properties uniquely shared with volant birds, particularly those occasionally utilising short-distance flapping >>

Dennis F. A. E. Voeten, Jorge Cubo, et al.  Wing bone geometry reveals active flight in Archaeopteryx. Nature Communications. 2018; 9 (923). doi: 10.1038/s41467-018-03296-8.  

venerdì 16 marzo 2018

# age: E3-ubiquitin ligases, the 'garbage disposal system' and the cell immortality

<< Human embryonic stem cells are considered to be immortal: they do not age, they can proliferate indefinitely >>

<< One of the mechanisms underlying immortality is the 'garbage disposal system' known as the proteasome >>

<< Of key relevance in the proteasome system are the so-called E3-ubiquitin ligases >>

AA << screened more than 600 proteins systematically and narrowed it down to 30 E3 ligases of special interest >>

AA << found that a global reduction in the proteolytic activity affects many intrinsic characteristics of embryonic stem cells, providing a link between immortality and up-regulated protein degradation >>

University of Cologne. On the immortality of stem cells. Mar 7, 2018.

Isabel Saez, Seda Koyuncu, et al. Insights into the ubiquitin-proteasome system of human embryonic stem cells. Scientific Reports. 2018; 8 (4092). doi: 10.1038/s41598-018-22384-9.     Mar 6, 2018.

mercoledì 14 marzo 2018

# gst: chemical waves exhibit fascinating patterns

<< Waves are known in many very different forms; as water waves, light waves or sound waves. But here we are dealing with something quite different - chemical waves >>

<< Typically, one imagines a chemical reaction like this: from specific initial reactants one obtains specific final products. But it does not need to be as simple as that. Self-sustaining oscillations may occur, i.e. periodic changes between two different states >>

<< On a polycrystalline surface, there are then different regions in which the cyclical process occurs at different frequencies. It is precisely this effect that creates those fascinating wave patterns. When a chemical wave moves across the surface and passes from the edge of one grain of crystal to another, it speeds up or slows down, similar to light passing from the air to water.  This changes the complex spiral wave structures according to the particular orientation of the grain surface >>

Vienna University of Technology. Chemical waves guide to catalysts of the future. Feb 20, 2018.

Yuri Suchorski, Martin Datler, et al. Visualizing catalyst heterogeneity by a multifrequential oscillating reaction. Nature Communication. 2018; 9 (600). doi: 10.1038/s41467-018-03007-3. Feb 9,  2018.

lunedì 12 marzo 2018

# game: a hypothesis to test a generic "generous tit-for-tat" approach to manage a self-catalytic (a cascade of period-doubling bifurcation) social transition dynamics

<< "La grande opportunità (..) è quella di tentare una 'mossa del cavallo': una scelta inaspettata, spiazzante, al limite del temerario" >>

che proponga  << un governo con gli elementi portanti del proprio programma, la cui guida sia affidata a una personalità fuori dei partiti, che scelga ministri tutti della società civile >>

"Modello Zagrebelsky per convincere il Pd". Intervista a Paolo Flores d’Arcais. Mar 11, 2018.

<< Adding "generous tit-for-tat" greatly increases the overall level of cooperation and can lead to long periods of steady cooperation >>

Nowak M, Sigmund K. Chaos and the evolution of cooperation.  Proc Natl Acad Sci USA. 1993; 90 (11): 5091-4. Jun 1, 1993.


<< The former child prodigy is 20 &wise beyond her years! @mohinidey17 talks to me of “when the person goes deeper than the technique” >> Jan 2, 2018


<< Amico,  qualunque  cosa suonerai ... >>

2113 - soniche a ramulo. Jan 28, 2007.

sabato 10 marzo 2018

# game: an interesting question of "worth" that circulates around a pulsatile meta-cycle of kidnapping and negotiation

<< There’s an interesting question of "worth" that circulates around this cycle of kidnapping and negotiation. Harold is dismayed that his company would rather negotiate than pay a full ransom for him, and that they’ve let their kidnapping insurance lapse. When Harold continually evades capture, he suddenly accrues more worth because he’s scarce. It’s a fascinating idea that’s explored with far more depth and nuance in the Danish drama "A Hijacking." >>

Katie Walsh. Film review: 'Gringo' lacks the intelligence to make a dark comedy work. Mar 8, 2018.

venerdì 9 marzo 2018

# astro: differential rotation in Jupiter

<< Jupiter's atmosphere is rotating differentially, with zones and belts rotating at speeds that differ by up to 100 metres per second >>

<< The discovery by the Juno spacecraft that Jupiter's gravity field is north–south asymmetric [..] demonstrates that the observed zonal cloud flow must persist to a depth of about 3,000 kilometres from the cloud tops >>

AA << find that the deep interior of the planet rotates nearly as a rigid body, with differential rotation decreasing by at least an order of magnitude compared to the atmosphere >>

AA << expect the outer, differentially rotating region to be at least three times deeper in Saturn and to be shallower in massive giant planets and brown dwarfs >>

Guillot T, Miguel Y, et al. A suppression of differential rotation in Jupiter’s deep interior. Nature. 2018; 555; 227 - 30.  doi: 10.1038/nature25775. Mar 8, 2018.

<< Scientists have long wondered what lies beneath Jupiter's surface. Now, using data from NASA's Juno mission, four research teams have published studies revealing incredible new information about the gas giant >>

Chelsea Gohd.  We Now Know What Lies Beneath Jupiter's Clouds. Mar 7, 2018.

NASA Juno Findings - Jupiter's Jet - Streams Are Unearthly.  March 7, 2018.

giovedì 8 marzo 2018

# sec: oops! also blockchain system seems to show some security vulnerabilities

<< Smart contracts - stateful executable objects hosted on blockchains like Ethereum - carry billions of dollars worth of coins and cannot be updated once deployed >>

AA << present a new systematic characterization of a class of trace vulnerabilities, which result from analyzing multiple invocations of a contract over its lifetime >>

Ivica Nikolic, Aashish Kolluri, et al. Finding The Greedy, Prodigal, and Suicidal Contracts at Scale. arXiv: 1802.06038 [cs.CR]. Feb 16, 2018.

Kristin Houser. Uh Oh: Blockchain May Not Be as Secure as We Thought. Mar 2, 2018. 

Mike Orcutt. Ethereum's smart contracts are full of holes. MIT Tech Rev. Mar 1, 2018.


# e-ai: an intriguing hypothesis: cheating that system will become near impossible. Jun 18, 2017