The United States is overhauling its chemicals law; now it must tackle carbon emissions.
Just as the dark-coloured pepper moth disappears from northern England, researchers are finally getting to the bottom of how it gained its colour.
Our fascination with telescopes and the worlds they reveal spreads beyond science into culture.
Satellites and research aeroplanes could offer a better, broader view of coral health.
Free open-access journal supported until 2022.
Launch in July will test new way to explore the Solar System — and beyond.
The Department of Energy says the US should fund ITER until 2018, and then re-evaluate its progress.
A computer cracks the Boolean Pythagorean triples problem — but is it really maths?
A rare bipartisan compromise endorsed by industry and the White House will give the US government new authority to ensure that chemicals are safe.
The Asian nation is spending big in the hope of winning a Nobel prize, but it will need more than cash to realize its ambitions.
Mathematician Lydia Bourouiba uses high-speed video to break down the anatomy of sneezes and coughs — and to understand infectious disease.
News & Views
The Sputnik Planum basin of Pluto contains a sheet of nitrogen ice, the surface of which is divided into irregular polygons tens of kilometres across. Two studies reveal that vigorous convection causes these polygons. See Letters p.79 & 82
The finding that antibiotics are pumped out of drug-tolerant bacterial cells by the TolC protein complex provides insight into how some cells, known as persisters, survive in the face of antibiotic treatments.
In photosynthesis, the plant photosystem II uses the energy in sunlight to oxidize water. The high-resolution structure of this crucial supercomplex has now been obtained using cryo-electron microscopy. See Article p.69
The finding of 175,000-year-old structures deep inside a cave in France suggests that Neanderthals ventured underground and were responsible for some of the earliest constructions made by hominins. See Letter p.111
Measurements of the electrical resistance and thermal conductivity of iron at extreme pressures and temperatures cast fresh light on controversial numerical simulations of the properties of Earth's outer core. See Letters p.95 & 99
Whole-genome sequencing of tumours from 560 breast cancer cases provides a comprehensive genome-wide view of recurrent somatic mutations and mutation frequencies across both protein coding and non-coding regions; several mutational signatures in these cancer genomes are associated with BRCA1 or BRCA2 function and defective homologous-recombination-based DNA repair.
Quantitative mass-spectrometry-based proteomic and phosphoproteomic analyses of genomically annotated human breast cancer samples elucidates functional consequences of somatic mutations, narrows candidate nominations for driver genes within large deletions and amplified regions, and identifies potential therapeutic targets.
X-ray crystallography, single-particle electron cryomicroscopy and electrophysiology were used to study the conformational changes that take place during the activation and inhibition of a mammalian GluN1b–GluN2B N-methyl-d-aspartate receptor.
A high-resolution structural study sheds light on processes of energy transfer within the photosynthetic water-splitting machinery of plants.
A sustained, neutral wind from the outer accretion disk is observed in the transient black hole V404 Cygni during a violent outburst; this unusual wind, which expands at one per cent of the speed of light and triggers a nebular phase once accretion drops sharply and the ejecta become optically thin, probably regulates the outburst evolution of the black hole.
A parameterized convection model and observations of the puzzling polygons of the Sputnik Planum region of Pluto are used to compute the Rayleigh number of its nitrogen ice and show that it is vigorously convecting, kilometres thick and about a million years old.
The volatile-ice-filled basin informally named Sputnik Planum is central to Pluto’s geological activity; this ice layer is organized into cells or polygons, and it is now shown that convective overturn in a several-kilometre-thick layer of solid nitrogen can explain both the presence of the cells and their great width.
Electric-field-induced charge separation (polarization) is the most fundamental manifestation of the interaction of light with matter and a phenomenon of great technological relevance. Nonlinear optical polarization produces coherent radiation in spectral ranges inaccessible by lasers and constitutes the key to ultimate-speed signal manipulation. Terahertz techniques have provided experimental access to this important observable up to frequencies of several terahertz. Here we demonstrate that attosecond metrology extends the resolution to petahertz frequencies of visible light. Attosecond polarization spectroscopy allows measurement of the response of the electronic system of silica to strong (more than one volt per ångström) few-cycle optical (about 750 nanometres) fields. Our proof-of-concept study provides time-resolved insight into the attosecond nonlinear polarization and the light–matter energy transfer dynamics behind the optical Kerr effect and multi-photon absorption. Timing the nonlinear polarization relative to the driving laser electric field with sub-30-attosecond accuracy yields direct quantitative access to both the reversible and irreversible energy exchange between visible–infrared light and electrons. Quantitative determination of dissipation within a signal manipulation cycle of only a few femtoseconds duration (by measurement and ab initio calculation) reveals the feasibility of dielectric optical switching at clock rates above 100 terahertz. The observed sub-femtosecond rise of energy transfer from the field to the material (for a peak electric field strength exceeding 2.5 volts per ångström) in turn indicates the viability of petahertz-bandwidth metrology with a solid-state device.
The evaporation and atmospheric oxidation of low-volatility organic vapours from mined oil sands material is shown to be responsible for a large amount of secondary organic aerosol mass—which affects air quality and climate change—observed during airborne measurements in Canada.
Using a laser-heated diamond-anvil cell to measure the electrical resistivity of iron under the high temperature and pressure conditions of the Earth’s core yields a value that means Earth’s core has high thermal conductivity, suggesting that its inner core is less than 0.7 billion years old, much younger than thought.
The thermal conductivity of solid iron at the pressure and temperature conditions that prevail in the cores of planets is measured directly using a dynamically laser-heated diamond-anvil cell, yielding values that support findings from ancient magnetized rocks that suggest Earth’s magnetic field has persisted since the Earth’s earliest history.
The mutation responsible for the black carbonaria morph of the peppered moth is identified as a transposable element within the cortex gene.
Wing colour patterning of multiple species in the butterfly genus Heliconius is controlled by differential expression of the gene cortex, a member of a conserved family of cell cycle regulators.
Two ring-like structures made of low walls of broken stalagmite pieces, deep in a cave in France, are described and dated to around 176,000 years ago, suggesting human-made construction within the period of early Neanderthals, although the function of the structures remains conjectural.
A similar neural ensemble participates in the encoding of two distinct memories, resulting in the recall of one memory increasing the likelihood of recalling the other, but only if those memories occur very closely in time—within a day rather than across a week.
The transcription factor Pitx2 is upregulated in injured neonatal and Hippo-deficient mouse hearts, where it interacts with the Hippo effector protein Yap to activate reactive oxygen species scavengers, thus preventing oxidative damage of the heart.
The activation of lipid X receptors (LXRs) in mouse liver not only promotes cholesterol efflux but also inhibits cholesterol synthesis simultaneously; this is mediated by the lipid-responsive long non-coding RNA LeXis, which is induced by a Western diet and orchestrates crosstalk between LXRs and the cholesterol biosynthetic pathway.
An allosteric inhibitor, EAI045, is reported that is selective for certain drug-resistant EGFR mutants, but spares the wild-type receptor; combination therapy of EAI045 with EGFR-dimerization-blocking antibodies is effective in mouse models of lung cancer driven by mutant versions of EGFR that are resistant to all previously developed inhibitors.
Ribosome biogenesis is a highly complex process in eukaryotes, involving temporally
and spatially regulated ribosomal protein (r-protein) binding and ribosomal RNA
remodelling events in the nucleolus, nucleoplasm and cytoplasm.
Hundreds of assembly factors, organized into sequential functional groups, facilitate and guide the maturation process into productive
assembly branches in and across different cellular compartments. However, the
precise mechanisms by which these assembly factors function are largely unknown.
Here we use cryo-electron microscopy to characterize the structures of yeast
nucleoplasmic pre-60S particles affinity-purified using the epitope-tagged assembly
factor Nog2. Our data pinpoint the locations and determine the structures of over 20
assembly factors, which are enriched in two areas: an arc region extending from the
central protuberance to the polypeptide tunnel exit, and the domain including the
internal transcribed spacer 2 (ITS2) that separates 5.8S and 25S ribosomal RNAs. In
particular, two regulatory GTPases, Nog2 and Nog1, act as hub proteins to interact
with multiple, distant assembly factors and functional ribosomal RNA elements,
manifesting their critical roles in structural remodelling checkpoints and nuclear
export. Moreover, our snapshots of compositionally and structurally different
pre-60S intermediates provide essential mechanistic details for three major
remodelling events before nuclear export: rotation of the 5S ribonucleoprotein,
construction of the active centre and ITS2 removal. The rich structural information
in our structures provides a framework to dissect molecular roles of diverse
assembly factors in eukaryotic ribosome assembly.