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According to research supported by the U.S. National Science Foundation, gene duplications being selected over evolutionary time — not the specialization of certain enzymes — allows wood rats to feed on creosote bush, a highly toxic desert shrub. The findings could aid in understanding genetic adaptations to poisonous foods in other mammals and even why individual humans metabolize drugs differently.

Around the end of the ice age, two species of wood rats in certain locations were forced to change their diet from juniper to creosote bush when the former died out in their native habitat and creosote invaded. The team of researchers, led by Denise Dearing, a distinguished professor in the School of Biological Sciences at the University of Utah, set out to understand just how these wood rats were able to switch to eating the toxic plant when so many other animals in the area couldn’t. They found that natural selection favored genetic changes leading to the duplication of genes that increased levels of existing detoxification enzymes to clear creosote toxins rather than modifying these enzymes to break down the toxic creosote faster.

“Rather than new tools specially designed for metabolizing this toxin, evolution made use of existing machinery — just by making more of it,” said Dearing. “That’s not to say it wasn’t a massive change. There wasn’t just an increase in

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Scientists have discovered the most distant and therefore oldest blazar ever seen. Labeled J0410–0139, the blazar is at the center of a galaxy 12.9 billion light years away and provides a rare glimpse into what the universe was like when it was less than 800 million years old.

The discovery challenges scientists’ current notions about the early universe, especially black holes. Namely: how big they could get, how fast they could grow, and how many could have existed. The findings are published in Nature Astronomy and The Astrophysical Journal Letters and made possible by multiple facilities, including the U.S. National Science Foundation Very Large Array, the NSF Very Long Baseline Array, the Chandra X-ray Observatory and the Atacama Large Millimeter/submillimeter Array (ALMA).

Detecting a blazar is rare to begin with. A blazar is a type of active galactic nucleus, or “AGN” for short. Supermassive black holes, sometimes millions to billions of times larger than the sun, are found within these nuclei. When feeding on matter, these black holes may project jets of charged particles shooting out in two directions and at almost the speed of light. If it is apparent that a jet is pointed almost directly at the viewer, the object is classified as a blazar.

With the jet of the blazar pointed right at Earth, one can see deep inside the galaxy to

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A new artificial intelligence-based method quickly solves complex math equations used broadly across many industries — and it’s faster running on a personal computer than traditional methods using supercomputers. The research was funded by multiple grants from the U.S. National Science Foundation and published in Nature Computational Science.

Engineers, scientists and others use partial differential equations to create complex models that can predict how fluids, electrical currents or other forces move through or impact various materials or shapes. These equation-based models can predict anything from how air moves around an airplane wing to how a building buckles under stress or what shape a metal car frame takes in a collision. This computationally heavy modeling work is time-consuming and generally requires a supercomputer to solve the many differential equations involved.

But now, a new AI-based framework — dubbed Diffeomorphic Mapping Operator Learning (DIMON) — is able to solve these equations much faster than other methods that use a supercomputer, and it can do so using just a regular personal computer.

“This is a solution that we think will have generally a massive impact on various fields of engineering because it’s very generic and scalable,” said Natalia Trayanova, a Johns Hopkins University biomedical engineering and medicine professor who co-led the research. “It can work basically on any problem, in any domain of science or engineering, to solve

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