Science - 27.03.2020

SCIENCE

PHOTO: SION ANG/SOPA IMAGES/LIGHTROCKET VIA GETTY IMAGES

Computer mimics neurons

ARTIFICIAL INTELLIGENCE | The computer

got a nose job. Intel researchers reported

last week that they trained Loihi, the com-

pany’s “neuromorphic” processing chip, to

identify 10 odors based on input from

72 chemical sensors—an ability they say

could be used to sniff out bombs and

drugs. After just one exposure, the chip

could identify each odor even when oth-

ers masked it. Unlike traditional circuits,

neuromorphic processors intermingle

logic and memory. That makes them

energy efficient, and good at artificial

intelligence tasks such as pattern recogni-

tion. Loihi contains more than 2 billion

transistors, which mimic the behavior of

130,000 neurons and 130 million synapses.

This month, Intel said, researchers could

access its neuromorphic computing sys-

tem, containing 64 Loihi chips, through a

cloud-based server.

A call for waterworks

GLOBAL WARMING | To adapt to climate

change and improve health and living

standards, countries should triple spend-

ing, to $114 billion annually, to build safe

drinking water and wastewater manage-

ment systems, the United Nations says in

a 22 March report. Warming temperatures

threaten to deplete groundwater supplies,

among other risks. But increased spend-

ing on unconventional technologies—such

as collecting water from fog and using

low-volume irrigation—could help provide

adequate supplies while decreasing the

overall carbon footprint of water and

wastewater utilities, the report says. Few

countries say much about water projects

in their plans for reducing carbon emis-

sions under the Paris agreement. And in

2016, water management projects directly

received only about 3% of financing to

mitigate and adapt to climate change. Half

the world’s population lacks safely man-

aged wastewater systems.

Iran, France swap detainees

INTERNATIONAL RELATIONS | A French

sociologist jailed in Tehran, Iran, since

I

n a victory for conservation, the Cambodian govern-

ment announced on 18 March that it is suspending for

10 years plans to build two hydropower dams on the

Mekong River. The move helps preserve a freshwater

ecosystem that, after the Amazon, is the world’s most

biologically diverse. It also supports a vast fishing in-

dustry. Cambodia now relies on hydropower for nearly 50%

of its electricity, but will turn to coal, natural gas, and solar

energy to meet its future power needs. The Mekong begins

on the Tibetan Plateau and flows through several countries,

including Cambodia and Vietnam, before emptying into the

South China Sea. It has been under increasing pressure from

development, pollution, and climate change; drought and

upstream dams in China have exacerbated recent low water

levels in the lower Mekong. Adding to the river system’s

woes, Laos opened two hydropower dams on the Mekong’s

main branch in the past 6 months, and Cambodia said it may

yet build dams on Mekong tributaries. Still, conservationists

praised Cambodia’s decision. Maintaining the free flow of

the lower Mekong is “the best decision for both people and

nature,” Teak Seng, Cambodia country director for the World

Wildlife Fund, said in a statement.

BIODIVERSITY

Cambodia halts Mekong dams

NEWS

IN BRIEF

Edited by Jeffrey Brainard

Cambodia’s Lower Sesan 2

hydroelectric dam,

built on a Mekong River

tributary and opened

in 2018, drew criticism.

1408 27 MARCH 2020 • VOL 367 ISSUE 6485