Science - USA (2019-01-04)

SCIENCE sciencemag.org 4 JANUARY 2019 • VOL 363 ISSUE 6422 39

RESEARCH

Edited by Stella Hurtley

IN SCIENCE JOURNALS

V I R O L O GY

Mobile detection

of Lassa virus

Lassa fever is a hemorrhagic viral

disease endemic to West Africa.

Usually, each year sees only a

smattering of cases reported, but

hospitalized patients risk a 15%

chance of death. Responding to

fears that a 10-fold surge in cases

in Nigeria in 2018 signaled an

incipient outbreak, Kafetzopoulou

et al. performed metagenomic

nanopore sequencing directly

from samples from 120 patients

(see the Perspective by Bhadelia).

Results showed no strong

evidence of a new strain emerg-

ing nor of person-to-person

transmission; rather, rodent

contamination was the main

source. To prevent future escala-

tion of this disease, we need to

understand what triggers the

irruption of rodents into human

dwellings. —CA

Science, this issue p. 74;

see also p. 30

PROTEIN TRANSLOCATION

Posttranslational

translocon architecture

About a third of proteins are

transported into endoplasmic

reticulum by the universally

conserved Sec61 protein-

conducting channel. Itskanov

and Park determined a cryo–

electron microscopy structure

of the Sec complex from yeast,

which mediates posttranslational

translocation of many secretory

proteins across the endoplasmic

reticulum membrane. The study

reveals how Sec63 activates

the Sec61 channel for substrate

polypeptide insertion. The

structure also explains the

mutually exclusive binding of

Sec63 and the ribosome to the

channel. —SMH

Science, this issue p. 84

CHEMICAL PHYSICS

C 60 at high resolution

It generally takes more energy

for molecules to vibrate than to

rotate. A vibrational absorption

band thus encompasses many

distinct concurrent rotational

transitions, but these tend to blur

together when the molecules

have more than a few atoms.

Changala et al. succeeded in cool-

ing C 60 fullerenes sufficiently to

obtain rotational resolution within

a C–C stretching band. Success

hinged on careful optimization

of argon buffer gas flow. Such

quantum state–resolved features

could aid characterization of

fullerene-type compounds in

exotic environments such as

interstellar space. —JSY

Science, this issue p. 49

ATO M I C P H YS I CS

Making a strongly

coupled plasma

Plasmas—gases of ionized

atoms and electrons—are

naturally formed at high temper-

atures, such as those reached in

the interiors of stars. Describing

plasmas theoretically is tricky

when they are in the strongly

coupled regime; reaching that

regime in the laboratory would

provide a valuable benchmark

for theory. To that end, Langin

et al. worked with a cold plasma

created out of atoms of stron-

tium that were ionized by laser

light (see the Perspective by

Bergeson). They used lasers to

cool the ions down to about 50

CROWD DYNAMICS

A crowd that flows like water

T

he behavior of large numbers of insects, animals, and

other flocks is often based on rules about individual inter-

actions. Bain and Bartolo applied a fluid-like model to the

behavior of marathon runners as they walked up to the

start line of the Chicago Marathon (see the Perspective by

Ouellette). They observed nondamping linear waves with the

same speed for different starting corrals of runners and at dif-

ferent races around the world. Their model should apply both

to this type of polarized crowd as well as to other groups, which

may help guide crowd management. —BG

Science, this issue p. 46; see also p. 27

Runners moving down Columbus Drive at the Chicago Marathon, October 2017

Fluorinated aryl groups couple

to form nanographenes

Kolmer et al., p. 57

CREDITS: (TOP TO BOTTOM) KOLMER

ET AL

.; DYLAN BUELL /STRINGER/GETTY IMAGES

Published by AAAS