In the greatest epic Ramayana, there are some interesting
characters. He was able to realize the mistakes and wrongdoings, tries to
intervene and moderate, but bound by warrior ethics, fights and gets
killed. Kumbhakarna (lit. pot-eared) is
a rakshasa and the younger brother of Ravana; despite his monstrous size and great
appetite, he was described to be of good character. It is stated that Kumbhakarna slept for six
months, and when he awoke, he ate everything in the vicinity !
Torpor
is a state of not being active and having very little energy. Many would know hibernation better. While
most mammals can adapt to the cold, many small mammals give up the struggle. As winter approaches, large mammals can often
migrate to warmer areas or grow a long, dense winter coat, but these options
are not open to small ones. Small mammals need a high metabolic rate to maintain body
temperature, they cannot increase this further when food is scarce. Nature has a solution – they give up the
struggle and allows body temperature to fall. The deep sleep allows them to conserve energy,
and survive the winter with little or no food.
Most
hibernators prepare in some way for the winter. Some store food in their
burrows or dens, to eat when they awake for short periods. Many eat extra food
in the fall while it is plentiful. It is stored as body fat to be used later
for energy. True hibernators go into such a deep sleep that they are difficult
to wake and may appear dead. Their body temperature drops and breathing and
heart beat slow down significantly.
To
differentiate, Torpor is a short-term reduction of body temperature on cool
days. Hibernation is an extended form of torpor. Could humans hibernate too ?
On
cold, dark days it is tempting to imagine shutting yourself away until the
warmer weather returns. Could humans ever hibernate in the same way animals do ?
Vladyslav Vyazovskiy, associate professor of neuroscience at the University of
Oxford has explained what torpor does to the body and how it could affect the
human body in an article for The Conversation.
Aside from providing a convenient way to avoid
winter, one reason to find out might be the advent of long-distance space
travel. A journey to our nearest planet
Mars would take around eight months using current technology. If we one day
hope to visit another star system, even if we could travel at the speed of
light, the journey would take years. Being
able to go into a state of long-term torpor would make such distances
considerably less tedious for the astronauts and conserve vital resources.
It's
still an open question but, at least in theory, we can't exclude that it might
be possible. Torpor appears to have
evolved to effectively fill the gaps during those periods of the year when
there is no need for certain animals to be out in the world, for example when
food is scarce. Technically it refers to a regulated state of reduced
metabolism, meaning the chemical reactions in an organism's body that keep it
alive slow down. Heart rate, breathing and energy consumption all dramatically
decrease and body temperature can also fall. When and for how long animals
enter torpor can vary hugely, from many months of the year, to just a few hours
a day over a period of a few months. Some animals, such as mice and
hummingbirds, enter a state of torpor daily. Others, such as bears, go into
prolonged periods of torpor during the winter, known as hibernation.
The
fact that large mammals such as bears and even primates, such as the fat-tailed
dwarf lemur of Madagascar can hibernate means that theoretically humans aren't
too big or energy-hungry to enter torpor. Nor does our evolutionary origin
prevent us from doing so, claims the expert. Last year, Dr Mark Schaffer from
SpaceWorks Enterprises in Atlanta suggested a proposal for putting astronauts
into hibernation. According to his plans, the astronauts would be put in stasis
using a system called RhinoChill. This would reduce body temperature by about
one degree per hour by supplying coolant through the nose. At a temperature of
between 32°C (89°F and 93°F), which takes six hours to reach, the crew would
enter stasis.
Stopping
the flow of coolant would then wake the crew when they arrive at their
destination. This means that on the journey to Mars, they could be placed in a
fairly small capsule. Lowering body temperature and metabolism mean cells need
less oxygen, enabling their survival in conditions when oxygen cannot be
delivered. This process of artificial cooling in humans appears similar to
spontaneous torpor in animals in that it includes reduced breathing, heart rate
and metabolism. But the key difference is that animals seems to 'know' the way to safely
and spontaneously enter torpor.
The
way to get to Mars using the minimum energy involves launching in a specific
window when the two planets are aligned in such a way that a craft can catch up
to the red planet when launched from Earth and enter orbit. This launch window
opens approximately every two years and two months, which is why mission to
Mars often launch and arrive at similar times – such as India’s recent Mars
orbiter and Nasa’s Maven mission. The
next window opens in April 2018, when Nasa’s next Mars mission – Insight – will
launch towards the red planet, while the as-yet unnamed Mars 2020 rover will do
the same when the next window opens in July 2020.
Interesting !!
With
regards –S. Sampathkumar
17th
Mar 2016-03-17
Science article credit : www.dailymail.co.uk/sciencetech/article-3495547