NEWS
IN BRIEF
886 News at a glance
IN DEPTH
888 Critics question whether novel
reactor is ‘walk-away safe’
Design approval nears for NuScale Power’s
small modular reactors, but deployment
plans slip 3 years By A. Cho
889 Paradox puts objectivity
on shaky footing
Quantum test of venerable thought
experiment suggests facts are relative
By G. Musser
890 Coronavirus creates a flu
season guessing game
SARS-CoV-2’s interactions with other
pathogens remain unknown as winter looms
By K. Servick892 Pandemic’s fallout on
malaria control appears limited so far
Countries avert disaster by resuming
bed net campaigns By L. Roberts893 Pandemic lockdown stirs up
ecological research
Biologists launch studies of how
wildlife around the world
responded to the “anthropause”
By E. Stokstad
PODCAST882 21 AUGUST 2020 • VOL 369 ISSUE 6506 sciencemag.org SCIENCE
21 AUGUST 2020 • VOLUME 369 ISSUE 6506PHOTO: DOUGLAS MAGNO/AFP VIA GETTY IMAGESINSIGHTS
POLICY FORUM
912 Knowledge transfer for large-scale
vaccine manufacturing
Massive, rapid production will require
firms to share know-how not just about
what to make but how to make it
By W. Nicholson Price II et al.PERSPECTIVES
915 The foundation
of efficient robot learning
Innate structure reduces data requirements
and improves robustness By L. P. Kaelbling917 A glycoprotein in urine binds
bacteria and blocks infections
Direct imaging of a human fluid illuminates
the molecular basis of urinary tract
protection from disease By W. Kukulski
REPORT p. 1005918 When the smallest details count
The type of liquid crystals formed by
smooth colloidal rods depends on their
degree of curvature By M. H. Godinho
RESEARCH ARTICLE p. 950919 Remodeling vasculature
to avoid blindness
Pathological vasculature marks itself for
repair by deploying neutrophil extracellular
traps By E. A. Podrez and T. V. Byzova
RESEARCH ARTICLE p. 934921 Immunotherapy with a sting
New agonists of an innate immune pathway
induce antitumor immunity in mice
By T. F. Gajewski and E. F. Higgs
RESEARCH ARTICLE p. 935; REPORT p. 993923 Past, present, and future
of lead–acid batteries
Improvements could increase energy density
and enable power-grid storage applications
By P. P. Lopes and V. R. Stamenkovic925 James G. Townsel (1935–2020)
Neuroscientist and devoted mentor
of diverse scientists By R. Nishi et al.BOOKS E T A L.
926 One step forward, two steps back
Interest groups and state-level political
inertia have stalled many of America’s clean
energy initiatives By S. H. Ali927 Ray Bradbury, luminary
of the space age, at 100
A new biography chronicles the golden
years of Earth’s first martian
By I. OckertCONTENTS
SPECIAL SECTIONMUD
894 INTRODUCTION
By D. Malakoff896 MUD ON THE MOVE
By D. Malakoff, N. Desai, and X. Liu898 A MUDDY LEGACY
A dozen years after two scientists showed
how centuries-old mud has smothered
many U.S. streams, their ideas are guiding
restoration efforts B y P. Vo o s e n902 THE MUD IS ELECTRIC
Bacteria that conduct electricity are
transforming how we see sediments
By E. Pennisi
904 Next up: a phone powered by
microbial wires? By E. Pennisi
PODCASTON THE COVER
The muddy
Markarfljót River
in Iceland carries
a heavy load of
sediment to the
sea. Throughout the
world, mud—a mix
of fine sediment
and water—is one
of the most common and consequential
substances. For better and worse, humans
are now heavily influencing how mud forms
and where it piles up. See page 894.
Photo: Arctic-Images/Getty Images9 06 A DAM BIG PROBLEM
A string of catastrophic failures
has raised alarm about dams meant
to contain muddy mine wastes
B y W. C o r n w a l l910 RED ALERT
Researchers are working to find new
uses for red mud, the caustic byproduct
of aluminum production By R. F. ServicePublished by AAAS