articles

La semana pasada, una masiva mina de carbón a cielo abierto, de 350 hectáreas en Druridge Bay, ganó su permiso de planificación. Esto hizo que Chris Goodall se preguntara: ¿y si la tierra se convirtiera en una granja solar en su lugar? Su descubrimiento es sorprendente: la energía solar en la costa sur de Inglaterra ya no cuesta más que el carbón: Sólo es cada vez más barata.

On the surface, trees may look stationary, but underground their roots -- aided by their fungal allies -- are constantly on the hunt and using a surprising number of strategies to find food, according to an international team of researchers.

The precision of the nutrient-seeking strategies that help trees grow in temperate forests may be related to the thickness of the trees' roots and the type of fungi they use, according to David Eissenstat, professor of woody plant physiology, Penn State. The tree must use a variety of strategies because nutrients often collect in pockets -- or hot spots -- in the soil, he added.

"What we found is that different species get nutrients in different ways and that depends both on that species' type of root -- whether it's thin or thick -- and that species' type of mycorrhizal fungi, which is a symbiotic fungus," said Eissenstat. "What we show is that you really can't understand this process without thinking about the roots and the mycorrhizal fungi together."

Tree species with thicker roots -- for example, the tulip poplar and pine - avoid actively seeking nutrient hot spots and instead send out more permanent, longer-lasting roots. On the other hand, some trees with thinner roots search for nutrients by selectively growing roots that are more temporary, or by using their fungal allies to find hot spots.

Hace doce años, una profesora de cierta primaria consideró beneficioso que sus alumnos vieran un documental sobre el calentamiento global. Tema bastante sonado pero que por alguna razón no impactaba en las personas como debería, como debemos buscar que impacte. Así, a mis ocho años, vi por primera vez a un oso polar asustado por los cambios en su hogar. Observé inmensas cantidades de basura en lugares que en ese instante creí lejanos. Me preocupé. ¿Por qué hubo diferencias entre mi sentir y el de otros niños? 

A lo largo de mi vida continué notando diferencias. Unos separaban la basura, otros preferían culpar al basurero de revolverla y así ahorrarse el crucial hábito. Vi personas capaces de caminar a la orilla de la playa sin sentir punzadas en el estómago al ver pañales flotando en el mar o ríos contaminados o personas que deben aprender a tolerar olores nauseabundos afuera de sus casas, porque ahí les tocó vivir, porque así siempre ha sido. Cambiar implica romper con las costumbres y es más fácil mantenernos quietos, a la espera de… ¿de qué? ¿De perderlo todo, perdernos entre hedores y enfermedades? 

Harvard researchers have identified a whole new class of high-performing organic molecules, inspired by vitamin B2, that can safely store electricity from intermittent energy sources like solar and wind power in large batteries.

The development builds on previous work in which the team developed a high-capacity flow battery that stored energy in organic molecules called quinones and a food additive called ferrocyanide. That advance was a game-changer, delivering the first high-performance, non-flammable, non-toxic, non-corrosive, and low-cost chemicals that could enable large-scale, inexpensive electricity storage.

While the versatile quinones show great promise for flow batteries, Harvard researchers continued to explore other organic molecules in pursuit of even better performance. But finding that same versatility in other organic systems has been challenging.

Hummingbirds are among nature's most agile fliers. They can travel faster than 50 kilometres per hour and stop on a dime to navigate through dense vegetation.

Now researchers have discovered that the tiny birds process visual information differently from other animals, perhaps to handle the demands of their extreme aerial acrobatics.

"Birds fly faster than insects and it's more dangerous if they collide with things," said Roslyn Dakin, a postdoctoral fellow in the UBC's department of zoology who led the study. "We wanted to know how they avoid collisions and we found that hummingbirds use their environment differently than insects to steer a precise course."

Note: Watch a video of the experiments here: https://youtu.be/6Z45BaswaOs

Scientists at UBC placed hummingbirds in a specially-designed tunnel and projected patterns on the walls to figure out how the birds steer a course to avoid collisions when they are in flight. They set up eight cameras to track the movement of hummingbirds as they flew through a 5.5-metre long tunnel.