A team of researchers from the US Naval Research Laboratory and Washington University has learned more about possible ways to store modern nuclear waste by studying an ancient natural fission reactor. In their paper published in Proceedings of the National Academy of Sciences, the group describes their study of cores taken from the natural Oklo nuclear reactor and what they found. Read more.
The world’s ancient civilizations were resourceful blends of language, ethnicity and popular culture. Entangled in the middle of Mesoamerican genesis was a precocious society whose attributes are now coming into sharper relief thanks in part to investigations financed by Brigham Young University’s New World Archaeological Foundation and the National Geographic Society, in collaboration with investigators from Mexico’s Instituto Nacional de Antropología e Historia (INAH) and National Autonomous University (UNAM). The ancient Zoque of western Chiapas appear to have shaped beliefs and traditions that became commonplace among their Mesoamerican neighbors. Read more.
Using high-intensity proton beams, researchers made significant quantities of titanium-44 (44Ti), which is particularly useful to the astrophysics research community in their studies of supernovae. In pursuit of alternative uses for this isotope, the researchers also designed a system that fixes this isotope on a surface. There, it decays into the much shorter-lived scandium-44g (44gSc). The scandium is vital to positron emission tomography (PET) scans of activities in the brain, heart and elsewhere. Read more.
In a world of quantum oddities, the phenomenon of indistinguishability, the impossibility of distinguishing between two quantum particles, remains notable. Superposition is one of the underlying causes of indistinguishability because there is no sure way to lock down an exact position of a quantum particle. This, in turn, makes it impossible to know which particle is which when two quantum particles interact in the same place. This leads to exotic particle behaviors, especially at low temperatures. Under those conditions, behavioral qualities of particles can resemble each other closely, causing phenomena such as Bose-Einstein condensates and superfluidity. Read more.
Myrtle warblers breed across much of Canada and the eastern United States, but winter in two distinct groups -- one along the Atlantic and Gulf coasts, another along the US Pacific Coast. They are also one of the few breeds of eastern warbler that have been able to extend their range into the far northwest of the continent.
"The Pacific Coast warblers migrate through the Vancouver area, but it's been a bit of a mystery exactly where they breed over the summer," says David Toews, who began the research while a graduate student at the University of British Columbia (UBC). Read more.
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