A review of net-zero emissions energy systems

Models show that to avert dangerous levels of climate change, global carbon dioxide emissions must fall to zero later this century. Most of these emissions arise from energy use. Davis et al. review what it would take to achieve decarbonization of the energy system. Some parts of … | Continue reading


@science.sciencemag.org | 5 years ago

Assessment of methane emissions from the U.S. oil and gas supply chain

Methane emissions from the U.S. oil and natural gas supply chain were estimated using ground-based, facility-scale measurements and validated with aircraft observations in areas accounting for ~30% of U.S. gas production. When scaled up nationally, our facility-based estimate of … | Continue reading


@science.sciencemag.org | 5 years ago

Artificial intelligence faces reproducibility crisis

The booming field of artificial intelligence (AI) is grappling with a replication crisis, much like the ones that have afflicted psychology, medicine, and other fields over the past decade. Just because algorithms are based on code doesn't mean experiments are easily replicated. … | Continue reading


@science.sciencemag.org | 5 years ago

Gut bacteria relieve epilepsy

MicrobiomeA high-fat and low-carbohydrate, or ketogenic, diet is used to treat children with refractory epilepsy. Olson et al. show that the ketogenic diet enriches populations of the gut commensal bacteria Akkermansia muciniphila and Parabacteroides spp. The presence of these sp … | Continue reading


@science.sciencemag.org | 5 years ago

Neural scene representation and rendering

To train a computer to “recognize” elements of a scene supplied by its visual sensors, computer scientists typically use millions of images painstakingly labeled by humans. Eslami et al. developed an artificial vision system, dubbed the Generative Query Network (GQN), that has no … | Continue reading


@science.sciencemag.org | 5 years ago

Crystallizing a memory

What is the physical basis of memory? What does it take to retrieve a memory in the brain? What would it take to activate or erase memories? In the early 20th century, the German zoologist Richard Semon coined the term “engram” to denote the physical manifestation of a memory in … | Continue reading


@science.sciencemag.org | 5 years ago

High burden and pervasive positive selection of somatic mutations in human skin

Within every tumor, a battle is being waged. As individual tumor cells acquire new mutations that promote their survival and growth, they clonally expand at the expense of tumor cells that are “less fit.” Martincorena et al. sequenced 234 biopsies of sun-exposed but physiological … | Continue reading


@science.sciencemag.org | 5 years ago

Organic matter preserved in 3B-year-old mudstones at Gale crater, Mars

The Curiosity rover has been sampling on Mars for the past 5 years (see the Perspective by ten Kate). Eigenbrode et al. used two instruments in the SAM (Sample Analysis at Mars) suite to catch traces of complex organics preserved in 3-billion-year-old sediments. Heating the sedim … | Continue reading


@science.sciencemag.org | 5 years ago

Experimental evidence for tipping points in social convention

Once a population has converged on a consensus, how can a group with a minority viewpoint overturn it? Theoretical models have emphasized tipping points, whereby a sufficiently large minority can change the societal norm. Centola et al. devised a system to study this in controlle … | Continue reading


@science.sciencemag.org | 5 years ago

Organic matter preserved in 3B-year-old mudstones at Gale crater, Mars

The Curiosity rover has been sampling on Mars for the past 5 years (see the Perspective by ten Kate). Eigenbrode et al. used two instruments in the SAM (Sample Analysis at Mars) suite to catch traces of complex organics preserved in 3-billion-year-old sediments. Heating the sedim … | Continue reading


@science.sciencemag.org | 5 years ago

Rules for Biologically Inspired Adaptive Network Design

In its vegetative phase, the slime mold Physarum polycephalum “slimes” its way through the world seeking food. As it explores, it links previously found food sources with tubular structures. Tero et al. (p. [439][1]) report that if food sources are deposited on a plate in a patte … | Continue reading


@science.sciencemag.org | 5 years ago

Reducing food’s environmental impacts through producers and consumers

Food is produced and processed by millions of farmers and intermediaries globally, with substantial associated environmental costs. Given the heterogeneity of producers, what is the best way to reduce food's environmental impacts? Poore and Nemecek consolidated data on the multip … | Continue reading


@science.sciencemag.org | 5 years ago

Reducing food’s environmental impacts through producers and consumers

Food is produced and processed by millions of farmers and intermediaries globally, with substantial associated environmental costs. Given the heterogeneity of producers, what is the best way to reduce food's environmental impacts? Poore and Nemecek consolidated data on the multip … | Continue reading


@science.sciencemag.org | 5 years ago

Some say artificial intelligence needs to learn like a child

In their adaptability, young children demonstrate common sense, a kind of intelligence that, so far, computer scientists have struggled to reproduce. Gary Marcus, a developmental cognitive scientist at New York University in New York City, believes the field of artificial intelli … | Continue reading


@science.sciencemag.org | 5 years ago

Recent Asian Origin of Chytrid Fungi Causing Global Amphibian Declines

Species in the fungal genus Batrachochytrium are responsible for severe declines in the populations of amphibians globally. The sources of these pathogens have been uncertain. O'Hanlon et al. used genomics on a panel of more than 200 isolates to trace the source of the frog patho … | Continue reading


@science.sciencemag.org | 5 years ago