Author Archives: ammarv

Concussions: Impacts on the Brain

The brain is a complex organ, and while researchers have made great strides in understanding its function and mechanisms, we still know relatively little about the consequences of damage to the delicate structure.

The brain is suspended in the skull cavity, and sharp accelerations can sometimes cause collisions between the unyielding bone of the skull and soft tissue, bruising the surface and damaging important neural connections within. This is known as a concussion, an injury common in contact sports where blows to the head are frequent.

A concussion can be harmful to anyone, but could the impact be greater on a developing brain, like that of a teenager’s?

Dr. Naznin Virji-Babul

Dr. Naznin Virji-Babul, a physical therapist and neuroscientist at the University of British Columbia, set out to discover the true extent of brain damage on concussed adolescents.

“The common perception of people is that your brain stops developing when you’re 3-5 years old. That’s not exactly true… the frontal areas of your brain are still developing when you’re a teenager,” she says, adding that this frontal area is what collides with the skull when a concussion occurs. The frontal and temporal lobes are most vulnerable to injury, and damage to these areas is associated with impairments of regular function. The study that her team conducted at UBC used Magnetic Resonance Imaging to gauge the extent of damage to the brain.

The study was conducted using a group of teen athletes, some of whom had experienced a sports-related concussion within the past two months and others who had not  Each athlete underwent an MRI scan which measured the rates of diffusion of the fluids within the brain.

The results were surprising to the team, who had expected to find clear evidence of damage, and lower rates of diffusion in the concussed group compared to the uninjured group.

“But it was completely opposite to what we had expected, we thought we would find a decrease in [one of the tests] but we found an increase… It was like solving a puzzle trying to find out what was so different.”

Diffusion Tensor Imaging scan for a healthy brain(left) and concussed brain(right)

Dr. Virji formulated a theory as to why the changes were different than expected: the neural damage in the brain was subtle, not outright breaking but causing smaller tears in the neuron which collect fluids and cause edema. This could throw off a diffusion tensor image but still indicates damage present in the brain long after the actual injury occurred.

“I wasn’t expecting to find changes in the kids who have had a concussion two months prior, but we still did… Kids and adolescents take longer to recover.”

These findings call to question the established guidelines concerning returning concussed athletes to play and school, as all of the concussed athletes scanned in the study had returned to their sport. Luckily, thanks to the findings of Dr. Virji and her team, new light is being shed on the nature of concussions on a teenager’s developing brain. This will hopefully lead to safer practices regarding the athletes care both during the game, and after.

Celebrating Hockey without injury

This podcast covers further the nature of this resistance by the public towards concussions in adolescents, and how the established safety measures are not adequate enough to prevent brain injury.

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For more information, feel free to watch this video on the impact of Dr. Virji’s research.

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By: Ammar Vahanvaty, Derrick Lee and Ashley Dolman

 

The Chameleons of the Sea

By: Ammar Vahanvaty

Not many people can relate to the experience Marine Biologist Roger Hanlon had when he came upon a seemingly innocuous piece of kelp in the shallows of the Caribbean. At first glance, an ordinary piece of underwater flora. But as he approached something incredible happened; a piece of the kelp suddenly turned stark white and the next few moments found Roger Hanlon blasted with a face-full of ink. He had encountered an octopus, so well camouflaged as to be mistaken for kelp. The offending octopus shot off into the distance only to settle next to another patch of ocean floor and change colours again to match its new surroundings. This event both awed and intrigued Hanlon, who, to this day, is exploring the magnificent abilities octopi and its cephalopod cousins share; the ability to camouflage.

What is camouflage?

Camouflage is the ability of an individual to blend into its surroundings. The most notable example of this technique in nature is the chameleon, who, in addition to its bulbous eyes and whip-like tongue, is famous for its ability to change its skin color to match the background. But even though the name chameleon is almost synonymous with camouflage in the public eye, they are not the masters of this ability. That honor falls to the cephalopod family, whose members include the squid, octopus and cuttlefish. These animals trump the camouflage ability of chameleons by not only shifting colour much quicker and with more accuracy, but by also adopting the texture of the object they are mimicking. This is what intrigued Hanlon the most as he began his research into these animals.

How does octopus camouflage work?

The mechanics are simple enough, at the microscopic level, animals harbour pigment cells called chromatophores, which lead to the variety of colour hues displayed by reptiles and fish, and the skin colour of humans etc. For the most part, these chromataphores are autonomic, and cannot be altered once set. But it appears cephalopods have control of each pigment cell in their bodies, and can alter the composition of the pigments at any moment to effect widespread and large colour changes throughout the animal. That part is fairly well understood, but less understood is the octopus and cuttlefishes’ ability to alter the pattern of their skin.

Hanlon and his team have identified three main forms of pattern generation for a cephalopod: uniform, mottled and disruptive. The bumps that allow an octopus to mimic the texture of the object they are up against appears to be formed by raising the papillae of the skin, much like controllable goose bumps. How exactly this process is achieved remains to be found.

The most vexing question though, is how does an octopus know what it is mimicking. Studies have shown that cephalopods are effectively colourblind, but they do not recognize the object’s colour through touch. So how do they do it? This is the question Hanlon is devoted to finding out, since  better understanding of this phenomenon could pave the way for advances in other fields. Who knows, an ‘invisibility cloak’ might not be so far off in our future.

For further reading into cephalopod coloration, Hanlon has created a nice primer to get started. 

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Will we ever leave our Solar System?

“Space: The final frontier” Capt. T. James Kirk

August 05, 2012  10:36am PDT

This day is not one that jumps out in the mind of the average person,  but for those that remember, it marked an astounding moment in the history of the National Aeronautics and Space Administration, better known as NASA; on this day, at this time, the wheels of the rover Curiosity, touched down safely on the surface of Mars.

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Though only the most recent of a handful of rovers humanity has already deposited on the surface of the Red Planet, Curiosity signifies a strengthening of our space-faring prowess, allowing mankind to look to the stars and truly entertain the notion: “We can go further.”

So how far have we gone?

In terms of manned missions, the furthest we have achieved is the Moon landings, the last of which occurred in December, 1972. Our unmanned endeavors have traveled further, since there is no need for pesky hindrances such as life support.

In 1977, the space probe Voyager 1 was launched. Its mission: to explore our  outer solar system. Travelling at a breakneck speed of 61,500 km/h, it has taken the small probe 35 years to reach the outer edge of our Solar system,  cementing it as the furthest man-made object from the Earth. NASA predicts the probe will reach the outer edge of the solar system sometime between 2013 and 2015.

NASA Artist concept of Voyager 1
(Source: NAACL.blogspot.ca)

 Can we go further?

Since we have reached the edge of our solar system, is it possible to reach and explore other solar systems in our galaxy?  Our Milky Way is comprised of billions of stars, out of which millions contain orbiting planets. So it seems feasible that we posses the means to reach these neighboring galaxies and extend our interstellar presence.

Not so fast, there is no doubt that the Voyager is travelling very fast, in fact, it is currently the fastest interstellar spacecraft in existence. But despite this incredible speed, fast enough to circumnavigate the globe 5 times in an hour, it might as well be travelling at a snail’s pace relative to the enormous interstellar distances between solar systems.

Distance between interstellar bodies is measured in Light Years, and the closest solar system to ours, Proxima Centauri  is 4.22 Light Years away. At Voyager’s current speed, it would take approximately 75,000 years for the probe to reach the solar system!

What does this mean?

Even as we advance to  where we can safely land rovers on Mars, and explore the outer reaches of our solar system, we still do not posses the means to conquer the massive distances between us and our interstellar neighbors  Still, NASA shows no signs of slowing down.

And trust me, there is plenty to do in our home solar system.

The Great Pacific Garbage Patch – A floating plastic island

 Plastics are ubiquitous, we use them everywhere in our daily lives: The bottles for our drinks, the packaging of our goods, even the insulation in our homes. But while these chemical polymers are undeniably useful, they are also everlasting. Every piece of plastic ever made is still here.

But where does it all go?

    The sad truth is, while some are recycled, a lot of it ends up in our oceans, where it is swept up in the ocean currents and deposited in Gyres. This process has continued unabated for close to 60 years, the result is The Great Pacific Garbage Patch, a 3.4 million square kilometer swath of plastic debris sitting on the surface of the North Pacific Ocean (Perkins 2010), three times the size of B.C. The vortex-like current of the gyre ensures the plastic remains localized to the area (Maximenko et al. 2012), and as it doesn’t degrade, it does nothing but affect the fragile ecosystem of the ocean and its inhabitants.

Plastic is left to gather in the Gyres

      In 2009, a team of graduate students from Scripps Institution of Oceanography in San Diego journeyed 1000 miles off the California coast to the eastern edge of the Garbage Patch.  There they collected samples and ran tests on the impact of the plastic on the area (Asian News International, 2009). They discovered  that the stomach contents of over 9% of the fish in the area contain plastic pellets . It might not seem like a large number but that accounts for over 12-24 thousand tonnes of ingested plastic a year (Ecology, Environment & Conservation, 2011) .

     And this garbage patch isn’t the only one floating in the vast expanses of the Pacific. The patch studied by the Scripps team was located in the northern region of the Pacific, but another patch has been discovered in the southern hemisphere by a team from the 5 Gyres Institute in California (Marcus et.al., 2013) .

How Does it Impact Us?

    There are a few answers to this, one of them is bio-accumulation of bisphenol A through ingestion of contaminated fish. Bisphenol A is a component of all manufactured plastics. The fish ingest the plastics and are in turn eaten by us, adding to the stores of bisphenol A in our systems (Canavan, 2010).

Chemicals affect a host of animals which we then eat.

         Even though the effects of plastic ingestion on humans hasn’t been well documented, there has been enough research done on its carcinogenic properties (Richter et al., 2007)  and neurological effects (Hajszan & Leranth, 2010)  that we can conclude it is in our best interests to keep our internal concentrations low. The presence of the Great Pacific Garbage Patch directly opposes this.

So What Can be Done?

    Thanks to pioneering efforts by people such as Capt. Charles Moore, awareness of the environmental effects of ocean plastic are better understood. As individuals, we can help by reducing the amount of plastic we waste by limiting our use of them, using cloth shopping bags and recycling bottles whenever we can.

Here Cpt. Moore describes his work on the Great Pacific Garbage Patch:

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     Until we as a global community are better educated about the possible harm our negligence is causing, the garbage patch will remain, a monument to our environmental apathy.

By Ammar Vahanvaty

References: 

 Anonymous. (2009, ). Ocean garbage patch. Journal of College Science Teaching, pp. 10.

DAVID CANAVAN. (2010, ). ‘Garbage island’: Lost at sea. The Bangkok Post

Eriksen, et al. Plastic pollution in the south pacific subtropical gyre. Marine Pollution Bulletin, (0) doi: 10.1016/j.marpolbul.2012.12.021

Hajszan, T., & Leranth, C. (2010). Bisphenol A interferes with synaptic remodeling. Frontiers in Neuroendocrinology, 31(4), 519-530.

Maximenko, N., Hafner, J., & Niiler, P. (2012). Pathways of marine debris derived from trajectories of lagrangian drifters. Marine Pollution Bulletin, 65(1–3), 51-62.

Perkins, S. (2010). Oceans yield huge haul of plastic. Science News, 177(7), p. 8.

Richter, C.A., et. al. 2007. In vivo effects of
bisphenol A in laboratory rodent studies. Reprod. Toxicol. 24, 199–224

Scientists discover extensive plastic debris in ‘great pacific ocean garbage patch’. (2009, ). Asian News International

Scripps study finds plastic in 9 percent of ‘garbage patch’ fishes. (2011). Ecology, Environment & Conservation, , 501.