Investigadores del Laboratorio de Física de Plasma de Princeton, del Departamento de Energía de Estados Unidos (PPPL) por primera vez han simulado la formación de estructuras llamadas "plasmoides" durante la Inyección Coaxial de “Helicidad” (CHI), un proceso que podría simplificar el diseño de plantas de energía a base de fusión, conocidos como “tokamaks”. Los resultados, publicados en la revista Physical Review Letters, implican la formación de plasmoides en el gas de plasma, caliente y cargado, que es el combustible de las reacciones de fusión. Estas estructuras (redondas) transportan corriente que podría eliminar la necesidad de solenoides, grandes bobinas magnéticas que serpentean por el centro de los tokamaks de hoy, para iniciar el plasma y completar el campo magnético que confina el gas caliente.
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El Niños and Bunny Booms
At times during the past 10,000 years, cottontails and hares reproduced like rabbits and their numbers surged when the El Niño weather pattern drenched the Pacific Coast with rain, according to a University of Utah analysis of 3,463 bunny bones. The study of ancient rabbit populations at a Baja California site may help scientists better understand how mammals that range from the coast to the interior will respond to climate change, says anthropology doctoral student Isaac Hart. He is first author of the study to be published in the July issue of the journal Quaternary Research.
Un gigante en peligro crÃtico de extinción, se reproduce asexualmente en estado silvestre
¿Son los machos verdaderamente esenciales para la reproducción? Las hembras, los reptiles y los tiburones que viven en cautividad en ocasiones han sorprendido a sus cuidadores por dar a luz a pesar de que, en lo que se tiene memoria, nunca han sido alojadas con un macho. Los científicos utilizaron análisis de ADN para resolver este misterio hace algún tiempo, lo que demuestra que estas crías fueron producidas por reproducción asexual, un proceso llamado partenogénesis, o "nacimiento virginal". Aunque estos eventos han captado gran interés público, no se sabía si esto alguna vez ocurrió en las poblaciones silvestres de estos animales.
Massive development possible near Grand Canyon National Park
More than 200,000 people flooded the U.S. Forest Service with comments over the last month calling for the agency to reject a plan for roads and infrastructure that would enable construction of a mega-development on the Grand Canyon’s doorstep.
The proposed roads, sewers and other utilities would pave the way for a multinational developer to transform the 580-resident community of Tusayan, Ariz., from a small, quiet tourist town into a sprawling complex of high-end homes, retail stores and restaurants only a mile from the Grand Canyon National Park boundary. The development threatens groundwater that feeds the Grand Canyon’s creeks, springs and seeps, endangering some of the park’s most important and biodiverse wildlife habitat.
The Dangers of Microbeads in Personal Care Products
Microbeads, those tiny plastic beads included in personal care products for exfoliating power, have been popular for a number of years, with a growing number of companies sneaking them into toothpaste, body scrubs, soap and more. That’s despite evidence that they cause significant environmental problems, an issue that’s led a number of states to ban them or seriously consider such bans in order to protect the environment. But there’s more: There’s evidence that microbeads are also harmful for human health.
EU considering new limitations on diesel engines in non-road machinery
As air pollution spikes in Europe’s cities prompt car-free days and talk of banning diesel cars, it’s easy to forget the other culprits behind the air quality crisis: diesel machines. Known in legislation by the innocuous term ‘non-road mobile machinery’, their air pollutant emission limits are now finally under revision.
The last directive dated back to 1997 and the new rules will set standards for decades to come. Air pollution is causing more than 450,000 premature deaths every year in Europe and a recent Eurobarometer survey confirmed that air pollution is now the biggest environmental concern of European citizens. Efficient regulation of emissions sources is therefore key to mitigating the exposure of citizens to air pollution.