Volume 545 Number 7655



News Features

News & Views

A firmer grip on the Hubbard model p.414

The Hubbard model describes the behaviour of interacting quantum particles, but many of its properties remain unknown. A system of ultracold atoms could provide the key to determining the model's underlying physics. See Letter p.462

doi: 10.1038/545414a

Education for stem cells p.415

Haematopoietic stem cells give rise to all lineages of blood cell, and their production in vitro has been a long-sought goal of stem-cell biology. Two groups now achieve this feat through different means. See Articles p.432 & p.439

doi: 10.1038/nature22496

Personalized test tracks cancer relapse p.417

Genomic analysis of lung-tumour evolution has been used to create personalized blood tests that enable successful clinical monitoring for early signs of cancer relapse — a promising step on the road to precision medicine. See Article p.446

doi: 10.1038/545417a

Quasars signpost massive galaxies p.418

The neighbourhoods of extremely bright astronomical objects called quasars in the early Universe have been incompletely probed. Observations suggest that these regions harbour some of the most massive known galaxies. See Letter p.457

doi: 10.1038/545418a

An immunity boost combats crop disease p.420

Plants precisely express some immune regulators by controlling the translation of messenger RNA into protein. This insight enabled a disease-resistant rice to be engineered without compromised productivity. See Letters p.487 & p.491

doi: 10.1038/nature22497

Global health estimated over two decades p.421

Reliably measuring global health is a huge challenge. Four papers published in 1997 laid foundations for future global-health estimates, but, despite subsequent advances, better integration of data systems and models is still needed.

doi: 10.1038/545421a




Impacts and mitigation of excess diesel-related NOx emissions in 11 major vehicle markets p.467

Vehicle emissions contribute to fine particulate matter (PM2.5) and tropospheric ozone air pollution, affecting human health, crop yields and climate worldwide. On-road diesel vehicles produce approximately 20 per cent of global anthropogenic emissions of nitrogen oxides (NOx), which are key PM2.5 and ozone precursors. Regulated NOx emission limits in leading markets have been progressively tightened, but current diesel vehicles emit far more NOx under real-world operating conditions than during laboratory certification testing. Here we show that across 11 markets, representing approximately 80 per cent of global diesel vehicle sales, nearly one-third of on-road heavy-duty diesel vehicle emissions and over half of on-road light-duty diesel vehicle emissions are in excess of certification limits. These excess emissions (totalling 4.6 million tons) are associated with about 38,000 PM2.5- and ozone-related premature deaths globally in 2015, including about 10 per cent of all ozone-related premature deaths in the 28 European Union member states. Heavy-duty vehicles are the dominant contributor to excess diesel NOx emissions and associated health impacts in almost all regions. Adopting and enforcing next-generation standards (more stringent than Euro 6/VI) could nearly eliminate real-world diesel-related NOx emissions in these markets, avoiding approximately 174,000 global PM2.5- and ozone-related premature deaths in 2040. Most of these benefits can be achieved by implementing Euro VI standards where they have not yet been adopted for heavy-duty vehicles.

doi: 10.1038/nature22086