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Tendencias 21

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Scientists find cell fate switch that decides liver, or pancreas? - 13/02/2014 / Leido 2 veces/ Comentarios 0

Stem cell scientists have a new theory for how stem cells decide whether to become liver or pancreatic cells during development. A cell's fate, the researchers found, is determined by the nearby presence of prostaglandin E2, a messenger molecule best known for its role in inflammation and pain. The...

Arctic marine mammals are ecosystem sentinels - 13/02/2014 / Leido 2 veces/ Comentarios 0

As the Arctic continues to see dramatic declines in seasonal sea ice, warming temperatures and increased storminess, the responses of marine mammals can provide clues to how the ecosystem is responding to these physical drivers. Fuente :

Cat parasite found in western Arctic Beluga deemed infectious - 13/02/2014 / Leido 0 veces/ Comentarios 0

Scientists have found for the first time an infectious form of the cat parasite Toxoplasma gondii in western Arctic Beluga, prompting a health advisory to the Inuit people who eat whale meat. Fuente :

Educados pero desempleados en el norte de Sri Lanka - 13/02/2014 / Leido 341 veces/ Comentarios 0

La Provincia Norte de Sri Lanka, que aún se recupera de las consecuencias de la guerra civil, tuvo motivos para celebrar cuando se anunciaron en diciembre los resultados de un examen realizado en todo el país. De los 16.604 estudiantes que participaron en la prueba, 63,8 por ciento obtuvieron las...

Superconductivity in orbit: Scientists find new path to loss-free electricity - 13/02/2014 / Leido 13 veces/ Comentarios 0

Researchers have combined atoms with multiple orbitals and precisely pinned down their electron distributions. Using advanced electron diffraction techniques, the scientists discovered that orbital fluctuations in iron-based compounds induce strongly coupled polarizations that can enhance electron...

Embryology: Scientists crack open 'black box' of development and see a 'rosette' - 13/02/2014 / Leido 3 veces/ Comentarios 0

We know much about how embryos develop, but one key stage -- implantation -- has remained a mystery. Now, scientists have discovered a way to study and film this 'black box' of development. This new method revealed that on its way from ball to cup, the blastocyst becomes a 'rosette' of wedge-shaped...

Mixed genes: Interactive world map of human genetic history reveals likely genetic impacts of historical events - 13/02/2014 / Leido 4 veces/ Comentarios 0

When individuals from different groups interbreed, their offspring's DNA becomes a mixture of the DNA from each admixing group. Pieces of this DNA are then passed along through subsequent generations, carrying on all the way to the present day. Researchers have now produced a global map detailing...

Psychologist shows why talking to kids really matters - 13/02/2014 / Leido 6 veces/ Comentarios 0

Exposure to child-directed speech sharpens infants' language processing skills and can predict future success. New work indicates early intervention can improve language skills in kids lagging behind. Fuente :

Crazy ants dominate fire ants by neutralizing their venom - 13/02/2014 / Leido 6 veces/ Comentarios 0

Invasive "crazy ants" are rapidly displacing fire ants in areas across the southeastern US by secreting a compound that neutralizes fire ant venom, according to a new study. It's the first known example of an insect with the ability to detoxify another insect's venom. Fuente :...

El petróleo altera las células del corazón de los atunes - 13/02/2014 / Leido 198 veces/ Comentarios 0

Un vertido de crudo puede causar la muerte de los peces al provocarles un paro cardíaco. Investigadores estadounidenses han descrito por primera vez el mecanismo por el que los hidrocarburos aromáticos policíclicos hacen que sus contracciones cardíacas se ralenticen y el ritmo del latido se vuelva...
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