Research advances mean that the time is ripe to ratify the ban on testing nuclear weapons.
The United Kingdom's new guidelines on alcohol consumption are a sound example of evidence-based policymaking.
World’s largest systematic identification project will use smart DNA-testing technology.
Epidemiologist who spearheaded response to outbreak is a popular choice.
Researchers aim to prevent recurrences by finding the virus’s natural host.
Fresh worlds found by K2 mission push beyond original discoveries.
Rumours frustrate physicists in a global competition to understand elusive particles.
Rapid changes in Tibetan grasslands are threatening Asia's main water supply and the livelihood of nomads.
Implicated in everything from traumatic brain injury to learning ability, boredom has become extremely interesting to scientists.
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A chronic lack of dietary fibre has been found to reduce the diversity of bacteria in the guts of mice. This effect is not fully reversed when fibre is reintroduced, and increases in severity over multiple generations. See Letter p.212
The detection of photons sufficiently energetic to ionize neutral hydrogen, coming from a compact, star-forming galaxy, offers clues to how the first generation of galaxies may have reionized hydrogen gas in the early Universe. See Letter p.178
The formation of blood vessels requires rapid proliferation of endothelial cells. The transcription factors FOXO1 and MYC have been found to regulate the metabolism and proliferation of vascular endothelial cells. See Letter p.216
An equation has been derived that allows the timing of the onset of glaciations to be predicted. This confirms that Earth has just missed entering a new glacial period, and is unlikely to enter one for another 50,000 years. See Letter p.200
Global assessments of variation in plant functional traits and the way that these traits influence competitive interactions provide a launching pad for future ecological studies. See Article p.167 & Letter p.204
The strength of synaptic connections between neurons needs to be variable, but not too much so. Evidence now indicates that regulation of such synaptic plasticity involves a complex cascade of feedback loops.
The authors found that the key elements of plant form and function, analysed at global scale, are largely concentrated into a two-dimensional plane indexed by the size of whole plants and organs on the one hand, and the construction costs for photosynthetic leaf area, on the other.
HIFα transcription factors are highly expressed in cancer stem cells from glioma; DYRK1 kinases inhibit the protein ID2 to modulate the level of HIF2α and the tumorigenic properties of glioblastoma-associated cancer stem cells.
Far-ultraviolet observations of the nearby low-mass star-forming galaxy J0925+1403 show that the galaxy is leaking ionizing radiation with an escape fraction of about 8 per cent, which is sufficient to ionize intergalactic medium material that is about 40 times as massive as the stellar mass of the galaxy.
The age of a young to middle-aged star can be determined from how quickly or slowly it rotates, but the relationship breaks down for old stars; models now show that old stars are rotating much more quickly than expected, perhaps because magnetic winds are weaker and therefore brake the rotation less effectively.
To be able to control the properties of a system that has strong electron–electron interactions using only an external electric field would be ideal, but the material must be thin enough to avoid shielding of the electric field in the bulk material; here pure electric-field control of the charge-density wave and superconductivity transition temperatures is achieved by electrolyte gating through an electric-field double layer transistor in the two-dimensional material 1T-TiSe2.
The global occurrence in water resources of organic micropollutants, such as pesticides and pharmaceuticals, has raised concerns about potential negative effects on aquatic ecosystems and human health. Activated carbons are the most widespread adsorbent materials used to remove organic pollutants from water but they have several deficiencies, including slow pollutant uptake (of the order of hours) and poor removal of many relatively hydrophilic micropollutants. Furthermore, regenerating spent activated carbon is energy intensive (requiring heating to 500–900 degrees Celsius) and does not fully restore performance. Insoluble polymers of β-cyclodextrin, an inexpensive, sustainably produced macrocycle of glucose, are likewise of interest for removing micropollutants from water by means of adsorption. β-cyclodextrin is known to encapsulate pollutants to form well-defined host–guest complexes, but until now cross-linked β-cyclodextrin polymers have had low surface areas and poor removal performance compared to conventional activated carbons. Here we crosslink β-cyclodextrin with rigid aromatic groups, providing a high-surface-area, mesoporous polymer of β-cyclodextrin. It rapidly sequesters a variety of organic micropollutants with adsorption rate constants 15 to 200 times greater than those of activated carbons and non-porous β-cyclodextrin adsorbent materials. In addition, the polymer can be regenerated several times using a mild washing procedure with no loss in performance. Finally, the polymer outperformed a leading activated carbon for the rapid removal of a complex mixture of organic micropollutants at environmentally relevant concentrations. These findings demonstrate the promise of porous cyclodextrin-based polymers for rapid, flow-through water treatment.
An iron-catalysed method for the direct 3H labelling of pharmaceuticals by hydrogen isotope exchange using tritium gas is reported; the site selectivity of the iron catalyst is orthogonal to currently used iridium catalysts and allows isotopic labelling of complementary positions in drug molecules.
A critical functional relationship between boreal summer insolation and global carbon dioxide concentration is proposed and tested with simulations; it accounts for the beginning of the past eight glacial cycles and predicts that the next one is unusually far off, even without the effect of anthropogenic emissions.
Data from millions of trees in thousands of locations are used to show that certain key traits affect competitive ability in predictable ways, and that there are trade-offs between traits that favour growth with and without competition.
New excavations in Sulawesi, where in situ stone artefacts associated with fossil remains of megafauna have been recovered from stratified deposits between 200,000 and 100,000 years ago, suggest that Sulawesi was host to a long-established population of archaic hominins.
In mice on a low microbiota-accessible carbohydrate (MAC) diet, the diversity of the gut microbiota is depleted, and the effect is transferred and compounded over generations; this phenotype is only reversed after supplementation of the missing taxa via faecal microbiota transplantation, suggesting dietary intervention alone may by insufficient at managing diseases characterized by a dysbiotic microbiota.
The transcription factor FOXO1 is identified as a crucial checkpoint of vascular growth, coupling the metabolic and proliferative activities of endothelial cells.
Epithelial tuft cells are shown to be the source of intestinal interleukin (IL)-25 that is required for activation of type 2 innate lymphoid cells (ILC2s), ILC2-regulated tuft and goblet cell expansion, and control of parasite infection.
Epithelial tuft cells secretion of IL-25 is shown to regulate type 2 epithelial responses to helminth parasite infection via an IL-13/IL-4Rα-dependent feedback loop.
Both DNA and RNA molecules have been shown to exhibit catalytic activity, but only the structure of catalytic RNAs has previously been determined; here the structure of an RNA-ligating DNA in the post-catalytic state is solved.
X-ray crystal structures of two distinct steps in the catalytic cycle of non-ribosomal peptide synthetases are described, offering the potential to generate novel products through engineering enzyme activity.
X-ray crystal structures are presented of each major step of the assembly-line synthesis by the initiation module of the nonribosomal peptide synthetase (NRPS) LgrA; the structures reveal large conformational changes, demonstrating a requirement for NRPSs to be very dynamic.