2020-01-25 New Scientist International Edition

25 January 2020 | New Scientist | 19

Immunology

Space Bionics

Pigeons inspire

flying machine

A robot that resembles

a pigeon can make tight

turns like a bird. PigeonBot

is powered by a propeller

and has wings that can

be controlled remotely.

Its average speed is about

40 kilometres per hour, a

bit slower than the average

pigeon (Science Robotics,

doi.org/djk4).

Metal has starring

role in bond movie

A chemical bond has been

filmed breaking and

forming for the first time.

Researchers fired a beam

of electrons at a molecule

composed of two atoms of

the metal rhenium. A bond

between them broke and

reformed. The researchers

filmed the atoms changing

shape as a result (Science

Advances, doi.org/djsb).

‘The blob’ is blamed

for avian massacre

A million seabirds that died

along the US west coast

were probably the victims

of an unprecedented

marine heatwave in the

Pacific. The killer appears

to have been “the blob”,

a vast, record-breaking

patch of warm water that

occurred off the west coast

of North America between

late 2013 and 2016

(PLoS One, doi.org/djk5).

Special nose cells

sniff out allergens

MICE have thousands of chemical

sensing nose cells that can trigger

an allergic reaction. Researchers

say this discovery could help us

fathom how the immune system

reacts to allergens we breath

in and why some people with

allergies lose their sense of smell.

We know that in people and

mice, inhaling allergens can cause

nasal inflammation. This prompts

a further allergic response driven

by immune cells, but we don’t

CLOSE to Sagittarius A*, the Milky

Way’s central, supermassive black

hole, six strange objects are defying

gravity. They look like clouds of gas

and dust, but behave like stars, and

scientists don’t know what they are.

The first two of these objects,

called G1 and G2, were discovered

nearly a decade ago. At the time,

astronomers thought they were just

gas clouds soon to be gobbled up.

But instead of being stretched out

and swallowed by the black hole,

the clouds continued to orbit it.

Anna Ciurlo at the University of

California, Los Angeles, and her

colleagues have spotted four more

of these weird clouds, which have

been called simply G objects. Each

of them is on the order of 15 billion

kilometres across, and from afar

they look like huge clouds that have

signatures of hydrogen atoms and

don’t emit very much heat.

Like the other two G objects, they

are orbiting Sagittarius A* the way

stars would, instead of falling in as

they would if they were just clouds

(Nature, doi.org/djmh).

Ciurlo suggests these could be

stars hidden by shrouds of gas and

dust thick enough to obscure their

light, possibly the result of stellar

smash-ups in which two stars

merge to leave a single large star

surrounded by debris. Leah Crane

fully understand the process.

To try to learn more, Lora

Bankova at Harvard University

and her colleagues isolated cells

from the noses of mice and sorted

them according to their shape, size

and the proteins on their surface.

They found chemical sensing

cells that react to allergens in the

air soon after they are inhaled.

These cells release molecules that

cause inflammation in the nose

before immune cells are delivered

to the nose in the bloodstream.

Bankova says she was surprised

to find mice have up to 30,000 of

these nose cells (Science, doi.org/

Orange jelly could

become robot skin

ARTIFICIAL electrified-skin made

of strange orange jelly can sense

a touch and heal itself. It could

be used to coat prostheses or to

cover robots so they can “feel”.

Many types of “e-skin” have

been made but are usually limited

to flat sheets that attach only to

flat surfaces, says Kyeongwoon

Chung at the Korea Institute of

Materials Science in South Korea.

Chung and his team made an

e-skin that can be 3D printed into

any shape. They made pyramids,

rings and a sort of cap that can fit

over a finger. Chung says it would

be possible to make a face shape.

The e-skin is made out of an

orange, jelly-like substance

composed mainly of water and

acrylic acid. The gel contains both

positively charged and negatively

charged particles, so when it is cut

or ripped, those particles attract

one another and it heals itself.

It can also detect if you touch

it. When a weak electric field is

applied to the skin via two wires,

a touch from a finger or any object

that conducts electricity makes

current flow through the gel.

The difference in the current

intensity at each wire allows the

point of touch to be identified

(ACS Applied Materials & Interfaces,

doi.org/djsg). LC

djs6). Equivalent chemical sensing

cells exist in the human nose, says

Bankova, but we don’t know if they

have a similar function.

The cells are mostly in the bit of

the nose involved in smell, which

hadn’t been thought to play a role

in allergic responses. This could be

why people with chronic allergies

can lose their sense of smell, says

Bankova. “It might be because

there is so much inflammation

in that area that we hadn’t

recognised.” Layal Liverpool

Could weaning babies earlier

help ease food allergy risks?

See p 20

Great balls of dust seem to

defy pull of vast black hole

LE
NT
INK

LA

B/S

TA
NF
OR

D^ U

NIV

ER
SIT

Y

IRI

NA

DM

ITR

IEN

KO

/AL

AM

Y^ S

TO

CK

PH

OT

O

Really brief

New Scientist Daily

Get the latest scientific discoveries in your inbox

newscientist.com/sign-up