Science - USA (2022-06-03)

PHOTO: MAURITIUS IMAGES GMBH/ALAMY STOCK PHOTO

SCIENCE science.org 3 JUNE 2022 • VOL 376 ISSUE 6597 1063

its core folds DNA ahead of its

track, whereas its peripheral

part specifies directionality by

holding onto the DNA double

helix. —DJ

Science, abm4012, this issue p. 1087

NEURODEVELOPMENT

Brain structure in ASD

Autism spectrum disorder

(ASD) may be characterized by

impaired social interactions, but

persons with ASD also struggle

with a variety of other behav-

ioral and intellectual difficulties.

Are individual differences better

understood as ASD subtypes

or as continuous variation?

Aglinskas et al. analyzed

MEMBRANES

Mixed-matrix membranes

using nanosheets

Selective adsorbents can

show enhanced separation of

components from mixed-gas

streams, but these materials

can often be difficult to fabri-

cate into large-scale, robust

membranes. Datta et al. report

the synthesis and charac-

terization of a mixed-matrix

membrane. They first describe

the synthesis of sheets of

the metal organic framework

(MOF) material AlFFIVE-1-Ni.

By using nanosheets instead of

the more commonly synthe-

sized MOF nanoparticles, the

authors were able to achieve

much better alignment, load-

ing fractions up to 60%, and

better polymer-MOF com-

patibility when embedding

the MOF nanosheets into a

polymer matrix. These mixed-

matrix membranes exhibited

improved carbon dioxide and

methane selectivity relative to

many other comparable ones,

as well as the ability to remove

hydrogen sulfide. —MSL

Science, abe0192, this issue p. 1080

DYNAMIC GENOME

Lots of loops

Protein complexes of the

structural maintenance of

chromosomes (SMC) family

organize genomes by extruding

DNA loops that are hundreds

of thousands of base pairs in

length. Molecular biologists

have wondered how these

motor complexes move in

consecutive steps that are sev-

eral times their own size while

consuming only a minimal

amount of ATP energy, as well

as why some reel in DNA from

only one side whereas others

do so symmetrically. By iden-

tifying the path of DNA though

the condensin SMC complex

at single-molecule resolu-

tion, Shaltiel et al. uncovered

a solution for how condensin

leapfrogs on chromosomes as

Alpine regions above the tree line, such as this site in Tyrol, Austria, are experiencing a mixture of higher productivity and reduced snow cover due to climate change.

CLIMATE CHANGE

Alpine snow loss and vegetation gain

M

ountains are experiencing more dramatic warming than

lower elevations, with increasing snowmelt and chang-

ing patterns of snowfall. Rumpf et al. examined how the

past four decades of climate change have influenced

snow cover and vegetation productivity in the European

Alps. Using remote sensing data, they found that snow

cover declined significantly, but so far this has been over less than

10% of the study region. Vegetation productivity has increased

across more than two-thirds of the area above the tree line, with

potential ecological and climate impacts. Feedbacks between snow

and vegetation will likely lead to even more pronounced changes in

the future. —BEL Science, abn6697, this issue p. 1119

Edited by Michael Funk

IN SCIENCE JOURNALS

RESEARCH