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Given the number of infections that can travel
through the air, it’s horrible when someone
coughs over us. But according to research by
scientists at the Massachusetts Institute of
Technology, it’s not just the person next to us
we should worry about: coughing spreads
droplets as far as six metres, and sneezing as
much as eight metres. These droplets stay
suspended in the air for up to 10 minutes. RM
How far do coughs
and sneezes travel?
Why do sheep all face the same way in a field?
Sheep tend to stand with their backs
to the wind when it is cold, but even
on sunny days, cows, sheep – and
even deer – all tend to face in the
same direction.
Research looking at satellite imageshas shown that they prefer to align
themselves north to south. It’s possible
that they might be sensitive to the
Earth’s magnetic field, but how they can
sense this, or why that might be useful,
isn’t currently understood. LVPHOTOS: ISTOCK, SCIENCE PHOTO LIBRARY X2Could we use antimatter radiation
to destroy cancer cells?
Radiotherapy uses an X-ray
beam to destroy tumours by
dumping enough energy into
their cells to break their DNA
molecules. The problem is
that the beam damages
everything in its path,
including healthy tissues,
particularly if the tumour is
deep in the body. Proton
therapy, which uses protons
instead of X-rays, is an
improvement on this. As
protons have mass, they
decelerate as they travel
through tissue and have the
greatest ionising effect only
once they’ve slowed down
enough to interact with theelectrons in other atoms.
This allows doctors to ‘focus’
the proton beam on the
tumour, without affecting
other tissues. Antiprotons
(the antimatter version of
protons) work even better
because they don’t just
ionise the atoms they strike,
they annihilate the protons in
the nucleus of the tumour
atoms. This releases gamma
rays, which do even more
damage to the tumour cells
in a targeted way. Sadly,
nowhere outside of CERN
currently produces enough
antiprotons to make this a
feasible treatment. LVA patient wears a mask to
immobilise their head
while undergoing proton
therapy on a brain tumour