giovedì 21 giugno 2018

# gst: to model a system that can "collapse without warning"

<< Volcanoes progressively weaken and may collapse without warning through hydrothermal alteration. These dangerous mass wasting processes occur less-frequently than eruptions or lahars but the resultant mass flows can be large in size, posing risk to local residents, and businesses. >>

<< Collapses are often multi-hazard events, with even small-scale landslides capable of triggering eruptions or creating break-out lahars. >>

<< These kind of events demonstrated the greater need to understand and assess this process >>

Gabor Kereszturi. Modelling volcanoes that "collapse without warning". Massey University. Jun 21, 2018.

martedì 19 giugno 2018

# gene: newtic1 to regenerate limbs

<< The newt, a group of urodele amphibians, has outstanding ability to repeatedly regenerate various body parts >>

<< In this animal, when the limb is amputated, a cell mass named the blastema appears on the stump and eventually gives rise to a new functional limb >>

AA << identified an orphan gene Newtic1, whose transcripts significantly increased in the blastema. Newtic1 was expressed in a subset of erythrocytes that formed a novel clump (EryC) >>

<< When the limb was amputated, EryCs were newly generated in the stump and accumulated into a distal portion of the growing blastema. >>

Roman M. Casco-Robles, Akihiko Watanabe, et al. Novel erythrocyte clumps revealed by an orphan gene Newtic1 in circulating blood and regenerating limbs of the adult newt. Scientific Reports. 8 (7455). May 10, 2018.

Novel gene in red blood cells may help adult newts regenerate limbs. University of Tsukuba. Jun 5, 2018.


# gene: the ability of the newt to safely regenerate parts of itself. Dic 30, 2017

lunedì 18 giugno 2018

# geo: low frequency sounds that resemble the shape of the tornillo seismic waves

AA << characterize and interpret a new type of infrasound signal originating from the summit of Volcán Cotopaxi (Ecuador) >>

<< This infrasound waveform is a slowly decaying sinusoid with exceptional low‐frequency (..) and high quality factor (..) and resembles the shape of tornillo seismic waveforms. >>

Johnson JB,  Ruiz MC, et al. Infrasound Tornillos Produced by Volcán Cotopaxi's Deep Crater. Geophysical Research Letters. doi: 10.1029/2018GL077766. Jun 13,  2018.

Volcano music could help scientists monitor eruptions. American Geophysical Union. Jun 15, 2018.

sabato 16 giugno 2018

# archeol: on the ancient turquoise

<< turquoise used by the Aztecs and Mixtecs likely derives from Mesoamerican sources and was not acquired through long-distance exchange with the Southwest >>

Alyson M. Thibodeau, Leonardo Lopez Lujan, et al. Was Aztec and Mixtec turquoise mined in the American Southwest?  Science Advances. Jun 13,  2018; 4 (6), eaas9370. doi: 10.1126/sciadv.aas9370

<< This work revises our understanding of these relatively rare objects and provides a new perspective on the availability of turquoise, which was a highly valued luxury resource in ancient Mesoamerica >>

<< These findings potentially re-shape our understanding of both the nature and extent of long-distance contacts between Mesoamerican and Southwestern societies (..) I hope this inspires people to be skeptical of claims >> Alyson Thibodeau.

New research unveils true origin of ancient turquoise. Dickinson College. Jun 13, 2018

venerdì 15 giugno 2018

# gst: Sustainability, Die-off, Collapse, Oscillation: 4 classes of traject. to depict interactions of a resource-intensive tech species with its host planet.

AA << have used the formalism of dynamical systems theory to explore a highly simplified model for the interaction of a resource-intensive technological species with its host planet. >>

AA << find four distinct classes of trajectories (..)

Sustainability: For these classes, stable equilibria (..) exist which can be approached monotonically. The population rises smoothly to a steady-state value. The planetary environment is monotonically perturbed from its initial value e0 and reaches a new steady state that can support a large population.

Die-off: For these classes, stable equilibria (..) exist which cannot be approached monotonically. The population overshoots the environment's carrying capacity, reaches a peak, and is forced to decline as the environment reaches its new steady state.

Collapse: For these classes, stable equilibria with nonzero population do not exist. In these cases the population experiences a rapid decline after reaching its peak value. It is noteworthy that collapse can occur even though the population has begun leveling off due to the civilization's switching from high-impact to low-impact energy modalities.

Oscillation: In this class, a stable limit cycle exists rather than an equilibrium. The population and the planetary environment cycle between high and low values. >>

Frank A, Carroll-Nellenback Jonathan, et al. The Anthropocene Generalized: Evolution of Exo-Civilizations and Their Planetary Feedback. Astrobiology. 18 (5), May 1, 2018. doi: 10.1089/ast.2017.1671.

Alien apocalypse: Can any civilization make it through climate change? University of Rochester. Jun 5, 2018.

lunedì 11 giugno 2018

# brain: understanding of zero even among honey bees

AA << trained individual honey bees to the numerical concepts of "greater than" or "less than" using stimuli containing one to six elemental features. Bees could subsequently extrapolate the concept of less than to order zero numerosity at the lower end of the numerical continuum. Bees demonstrated an understanding that parallels animals such as the African grey parrot, nonhuman primates, and even preschool children. >>

Scarlett R Howard, Aurore Avargues-Weber, et al. Numerical Ordering of Zero in Honey Bees. Science, 360 (6393), 1124-1126. 2018 Jun 8. doi: 10.1126/science.aar4975.


questa news la devo a mia moglie Tamara, anche lei pulsatile nomade di labirinti ...