Q&ADEAR DOCTOR...DELICATE ISSUES DEALT WITHBYSCIENCE FOCUS EXPERTSGel polish contains small molecules
called monomers. When you put
your hand under the ultraviolet
(UV) nail lamp, the UV radiation
triggers a chemical reaction that
causes the monomers to link
together to form long polymer
chains, setting the gel. The result is
a tough, flexible nail polish.
In 2009, US researchers sparked
concern with an article describing
how two nail bar regulars had
developed skin cancer on the backs
of their hands. However, the
researchers weren’t able to make
any strong conclusions about
whether the UV nail lamps were
responsible, and a separate 2018
review of the literature concluded
that the cancer risk from nail lamps
is low. Nevertheless, the authors of
the review recommend using
fingerless gloves or sunscreen to
protect the hands while under
the lamp.
Finally, the nail filing that occurs
before the polish, and the soaking
in acetone to remove gel nails, can
make nails more brittle and likely
to split. So treat yourself, but it
might be worth planning in some
gel-free periods, and protecting
your hands.ED
I’DLOVE TO TREAT
MYSELF TO A GEL
MANICURE, BUT ARE
THEY BAD FOR ME?
I HATE PUBLIC SPEAKING. IS ‘IMAGINE THE
AUDIENCE NAKED’ REALLY THE BEST
ADVICE FOR OVERCOMING NERVES?Thisadvice has been around for years. The idea is that it will make your
audience seem less threatening and so reduce your nerves. However,
public speaking experts say it’s an unwise technique – after all, the key
to being an effective presenter is to respect and engage your audience,
not to see them as the enemy or to mock them (if you have a vivid
imagination, the strategy could also be overly distracting!).
To calm your nerves, you’re better off using a technique known as
‘cognitive reappraisal’. Research at Harvard Business School has
shown that speakers who deliberately reevaluate their nerves as
excitement rather than anxiety (for example, by saying “I am excited”
out loud) perform better than those who try to calm themselves down.
More generally, one of the best things you can do is to prepare
thoroughly. Make sure your speech does not overrun, practise in front
of friends and family, and visit the venue ahead of time if you can.
Finally, create some ‘if-then’ plans to help you cope, such as “if I begin
to feel overwhelmed, then I will take a deep breath and refocus”.CJADAMKING,
HUDDERSFIELDWHYARESUNSPOTSBLACK?Sunspots are areas
of the Sun’s
photosphere (the
visible surface) that
are significantly
cooler than the
surrounding regions.
Although the exact
details of sunspot
formation are not
fully understood,
they are coincident
with areas of
increased magnetic
field. These intense
magnetic fields
appear to suppress
the release of heat
into the photosphere,
thus making
sunspots cooler than
their surroundings by
a couple of thousand
degrees Celsius. This
means that sunspots
are only about a third
as bright as the
surrounding
photosphere, and it’s
this contrast in
brightness that
makes them appear
dark, even black. If
you could pluck a
sunspot from the Sun
and put it in the night
sky, it would actually
be about as bright as
the surface of the
Moon as seen from
Earth.AGuDog food is nutritionally balanced for the canine metabolism, so it
has more fat and less protein than we need, and it’s also enriched
with vitamin A, which can be harmful in high doses to humans in the
long term. None of this should be a problem if you’re only eating one
tin. More of a risk is that – although most tinned pet food is made
from ingredients that are left over from human food manufacture- stringent human food safety regulations don’t always apply, and
there have been incidents of contaminated pet food. So it’s probably
best to find an all-night café!LV
I’MHUNGRY, THE SHOPS ARE SHUT AND
ALL I HAVE IN MY CUPBOARD IS DOG
FOOD. WOULD IT BE SAFE TO EAT?