Communicating Science 13w210

Oxytocin: The reason for monogamy?

Posted on February 10, 2014 by brendanguyen | 4 comments

To the insecure, the girlfriends, the wives and the crazies: I guess you can finally put an end to splurging on beauty products! It turns out it is not the endless hours we have spent before date nights that reminds your man to remain faithful to you – it is actually because of the hormone, oxytocin. Oxytocin is a hormone secreted by the pituitary gland. It is often referred to as the “love hormone” or the “cuddle hormone” since it’s released during hugging, touching, and other intimate moments.

Many people mistakenly call oxytocin the “love hormone” when “attachment hormone” or “bonding hormone” would be more suitable. This video outlines other chemicals released in the brain through the various stages of romance!

Chemical Structure of Oxytocin
Source: Wikimedia Commons

Monogamy is not prevalent in mammals. In fact, humans are part of the few species that serve as an exception to this and it is oxytocin that is responsible for this partner bonding.

Larry Young, a professor of psychiatry from Emory University in Atlanta, examined prairie vole brain activity during bonding. Young compares these rodents’ behaviour to humans, in that their oxytocin concentrations rise during bonding. It was observed that monogamous male voles had a strong desire for their partner and acted in a hostile manner towards other females.

This video outlines Young’s findings of prairie vole brain activity with regards to bonding.

Dr. René Hurlemann, an executive senior physician from Bonn University Medical Center, and researchers from Ruhr University of Bochum in Germany and the University of Chengdu in China, collaborated to examine the effects of oxytocin in humans, specifically in males. They showed pictures of their female partners and pictures of other women to 40 heterosexual males. These males were given a dose of oxytocin (in a nasal spray form) and then a placebo, on another day.

The Good?
After being administered oxytocin, it appeared that their reward system, in their brain, was very active when shown pictures of their female partners. In fact, according to their brain activity, males found their partners more attractive than other women.

The Bad?
With oxytocin activating the reward system between lovers, Hurlemann suggests that the lack-of oxytocin might be responsible for the immense sadness and depression people experience after parting ways with their partner. Individuals experience a state of withdrawal, with the reward system being significantly less active.

Your best bet for faithfulness would be to increase your oxytocin concentration! Give your special someone a hug or two and complete a challenge together! This should increase activity in your reward system and remind your significant other to remain faithful!

-Brenda Nguyen

4 Comments

Posted in Biological sciences, Science in the news

Tagged brain, hormone, love, monogamy, oxytocin, pituitary

Science behind the Morning Wood

Posted on February 10, 2014 by Kevin Lee | 2 comments

It happens to grown men, little boys, and even male still in utero: the ability to pitch a tent in the morning in your pyjamas without any camping skills.

All jokes aside, nocturnal penile tumescence, otherwise known as morning wood, is a phenomenon that males experience on a daily basis without a full understanding of how and why it happens.

An experience we men are too familiar with

It is revealed by studies that morning wood occurs numerously during sleep, and is in direct correlation with the sleep cycle that alternates between levels of sleep.

One of the most important stages of sleep is the Rapid Eye Movement (REM) stage. An average male undergoes REM stage around 4-8 times over regular sleep, and at this stage of sleep certain neurotransmitters decrease.

Of the many neurotransmitters that decrease during REM sleep, Norepinephrine is one of them.

Norepinephrine structure

Norepinephrine acts as a vasoconstrictor that regulates erections. Metaphorically, it is used as a stop sign chemical that inhibits blood flow into penis muscles and thus inhibiting the erection.

In REM sleep, it is proved that norepinephrine levels drastically drop and allow vasodilation, increasing the blood flow into the penile muscles.

So why is morning wood important?

To answer the question, increased blood flow into the penis muscles, like any other tissue in the body, increases oxygenation. This increased blood flow and oxygenation is critical in repairing and maintaining functionality.

Another question one might bring up is why we always wake up to this phenomena. The answer is because we most usually wake up just out of REM sleep and thus observe the remnants of this sleep stage.

It is profound how such phenomena we face everyday without much thought can be the result of chemical reactions in the male body. Perhaps next time you wake up with morning wood you’ll be assured that you’re fully repaired and fully functional.

2 Comments

Posted in Biological sciences, Science communication

Tagged Erections, MorningWood, Nocturnal Penile Tumescence, REM, Sex, sleep cycle

Omega-3: What’s “Fishy” about it?

Posted on February 10, 2014 by nakisa kiai | 1 comment

You may have heard of the importance of omega-3 fats into your diet and the numerous health benefits that come from it. Incorporating omega-3 fats into our daily diet has proven to have very notable results in decreasing risk of heart disease, cancer, dementia, Alzheimers disease and depression. All of which sound like things every person would want to avoid!

So, what are these magical fats?

There are 3 types of omega-3 fats, ALA (alpha-linolenic acid), EPA (eicasapentanoic acid) and DHA (docosahexaenoic acid). Surely it would be ideal to incorporate all of the three into our diet, but each can come from different sources. EPA and DHA are commonly found in fish– salmon, mackerel, anchovies, sardines etc. ALA can be found in soybeans, walnuts, flaxseeds as well as milk, eggs and margarine.

Sources of Omega-3 Fats Image: Mr-Ginseng.com

Wait, did you say fish?

For those of us on the West Coast who are fish fanatics, this should be no problem at all. What if you aren’t, though? Does this mean that you are doomed to an omega-3 deficiency?

The good news is that you can get your source of omega-3 fats from many other food sources besides fish! When you walk down the grocery isle, you will probably recognize labels that say “omega-3”, “ALA”, “EPA” or “DHA”. Many products in the dairy isle as well as some grains and cereals have these added benefits.

But what happens if you are a vegetarian or a vegan (on top of despising the taste of fish)? There are several omega-3 supplements available on the market that meet this dietary need. It may be smart, however, to consult with a health care professional before starting on a supplement.

Omega-3 Supplements Image: Jamieson Vitamins

Of course, eating fatty fish is a major source of omega-3 fats and many other health benefits, but this should also be done with caution- women who are pregnant or breastfeeding should be careful about their fish intake due to risk of higher levels of mercury.

Bottom line- eat healthy and know your options! Omega-3 fats do not need to be “fishy”!

Blog post by: Nakisa Kiai

1 Comment

Posted in Issues in science, Public engagement, Science in the news, Uncategorized

Tagged balanced diet, fish, health, heart disease, omega-3, supplements

Gold Medal Physics at the Olympic Games

Posted on February 10, 2014 by Sydney Honsberger-Grant | 3 comments

The 2014 Olympics in Sochi, Russia have begun, and for the past few days I’ve been watching various events with continuous awe. Initially, I was astonished by the sheer athleticism on display, but eventually I started wondering about the physical processes behind it all. How can a figure skater launch his teammate into the air and catch her while moving across the ice? How can speed skaters glide without losing significant velocity to friction? How does a mogul skier, like Canadian champion Alex Bilodeau, make all those twists and turns midair?

Alex Bilodeau’s gold-winning jump. Source: The Guardian.

For those of us who can’t call to mind any explanation for these questions, NBC Learn has provided some answers. They’ve teamed up with the National Science Foundation (NSF) to elucidate some essential physical principles utilized during the Winter Games. The 10 videos on NBC Learn’s website highlight a variety of events, including bobsledding, half pipe, and – in my opinion, the most fascinating sport – slopestyle skiing.

These videos use interviews with both athletes and scientists to illustrate their points. The athletes themselves discuss how they move and react in each event; scientists then go on to explain the detailed principles of these motions in a qualitative way. These complementary perspectives allows the viewer to get a well-rounded, comprehendible idea of the physics surrounding each sport, without getting smothered by scientific jargon. Thus, the Olympics have become a surprising conduit for scientific learning.

Mikael Kingsbury’s arm positions during a jump. Source: Montreal Gazette.

So, based on what NBC Learn has shared on ski jumping, how does Bilodeau execute his aforementioned twists and turns? First, he has to harness enough angular momentum upon taking off to ensure that he can continue spinning mid-air. He does this by twisting his torso and bending his legs, much like a loaded spring. Once he’s made the jump, he can manipulate the orientation of his arms to achieve the desired twists. For instance, lifting one arm up and keep the other down will cause a shift in his centre of mass that will produce a certain degree of twisting, as opposed to keeping both arms down. If he wants to slow his spin in preparation for landing, he can widen his arm span and increase his moment of inertia, thereby decreasing his angular velocity. These procedures, and more, go into making a gold-medal jump.

Physical model of a jump. Source: Wikipedia.

Although I’m still far from constructing a detailed physical model of a slopestyle jump (and even further from actually executing one on the hill), these videos have certainly enlightened me to the applications of some basic laws of physics. It’s amazing that some principles are consistently used among sports; for example, both Bilodeau and figure skater Patrick Chan would know how to alter their moments of inertia with their arms. My unifying outlook after watching the videos is that the utilization of physics’ basic laws are widespread and relevant in even non-academic situations – and it might be worthwhile to expand on these concepts.

If you’re captivated by the Olympics, but have trouble grasping the physical side of the events, definitely check out NBC Learn’s videos. They’re interesting and informative, and you’ll be wiser the next time you cheer on your home team.

Alex Bilodeau’s gold celebration. Source: CTV News.

Sydney Honsberger-Grant

3 Comments

Posted in Public engagement, Science communication

Tagged Olympics, physics

The Golden Ratio

Posted on February 10, 2014 by usagi | 3 comments

The golden ratio is a special number that is approximately equal to 1.618 and is symbolized by the Greek letter Phi. It has fascinated scientists for years and is found hidden almost everywhere on earth. The ratio was actually derived from the Fibonacci sequence, which looks something like this: 0, 1, 1, 2, 3, 5, 8, 13 and so on. Each number is just the sum of the two numbers before it, and it looks quite simple. However when examined in depth, mathematicians and scientists realized it seems to be hiding a secret to the universe.

The Fibonacci sequence is named after Leonardo Fibonacci who actually came up with the sequence when calculating the mating sequence of rabbits over the course of one year. The sequence itself doesn’t look special at all, but when you take each number in the series and divide it by the previous number, the ratios began to approach 1.618 as the numbers get bigger. That number is now known as “The Golden Mean”.

An example of where the golden ratio is found on earth is in the Pyramids. If the base of the pyramid is considered to be 1 unit, then its sides are calculated to be 1.618 units and the height is the square root of 1.618 units tall. The golden ratio is also frequently found in nature, particularly in flowers and trees. For example, the number of petals in a flower follows the Fibonacci sequence: Lily has 3 petals, buttercups have 5 petals, and chicory has 21 petals. All of the number of petals in different flowers are all just numbers found in the Fibonacci sequence. Each petal is placed at 0.618 per turn to allow for the maximum exposure to sunlight. In addition to that, the number of seeds in a sunflower is arranged in a spiral shape and when the spirals are counted, the total also matched a Fibonacci number.

Spirals found in sunflowers
Source: http://upload.wikimedia.org/wikipedia/commons/thumb/4/4f/Aeonium_tabuliforme.jpg/220px-Aeonium_tabuliforme.jpg

Similar patterns are found in fruits and vegetables such as pineapple and cauliflower. Shells, spiral galaxies and hurricanes also seemed to contain the golden ratio when put into a “golden rectangle”. A golden rectangle is a rectangle whose side lengths are in the golden ratio.

Golden ratio found in space
Source: http://io9.com/5985588/15-uncanny-examples-of-the-golden-ratio-in-nature

Last but not least, the golden ratio is found also in the human face. People whose face proportionality approached 1.618 are deemed more attractive- although every person’s body is different, the average across different populations still tend towards the golden ratio.

Posted by Jean Wang

3 Comments

Posted in Uncategorized

Tagged Fabonacci's Sequence, Phi, The Golden Ratio

Anti-wrinkle cream: a bottle full of empty promises?

Posted on February 10, 2014 by richellee | 1 comment

Throughout generations, there have been countless formulations of anti-wrinkle creams all claiming the same thing: younger, healthier, and brighter skin. The American Academy of Dermatology states that each year billions of dollars are spent on anti-aging face creams, all in an attempt to reduce the “signs of aging”. With formulations costing an average of $150 and upwards of $5,000 a jar, are consumers actually achieving their “naturally younger” skin?

Anti-aging in the media
Source: Wikimedia Commons

As we age our cells’ production of collagen, a protein found in connective tissues, naturally starts to slow. Thus skin begins to lose its elasticity, the epidermis thins, and wrinkles emerge. Other factors, such as UV light or cigarette smoke, can also accelerate the process. It is this natural process of aging that skin-care companies claim to be able to reverse.

Below is a typical anti-aging skin care advertisement, from Neutrogena:

Besides soft-voiced women, anti-aging ads often highlight certain “miracle” ingredients. What is actually in the jar?

Moisturizers: standard formulation to hydrate skin
Peptides: proteins used to hydrate skin, but it is uncertain as to whether they penetrate deep enough to “remove” wrinkles
Alpha hydroxy acids (AHAs): exfoliate skin and remove dead cells (most common are citric and lactic acid)
Retinol: a form of vitamin A, a key ingredient found in numerous skin-care products
Anti-oxidants: substances to reduce free radicals, found in numerous forms (vitamin A, vitamin C, vitamin E, etc.)
Sunscreens: used to protect against UV damage

Out of the numerous chemicals listed above, only retinol has actually been confirmed to visibly reduce the appearance of wrinkles. A study performed by Kafi et al. 2007 proved the effectiveness of retinol over a 12 week period, by injecting high concentrations into the patients’ skin daily. Another proven alternative is topical prescription retinoids (a derivative of vitamin A). However, both of these options involve doses of highly concentrated retinol. Such levels are not even close to the sub-concentrations you find in over-the-counter creams, of which have not been shown to be effective.

Vitamin A or Retinol
Source: Wikimedia Commons

The matter of fact remains that any moisturizer, whether $5 or $5,000, will temporarily plump up the look of skin until you wash it off. I do not negate the ingredients found in the creams, as some, such as vitamin C, are beneficial to our skin regardless of age. However, as it stands, none of them have been proven to reduce the appearance of wrinkles in the low concentrations present. In conclusion, the next time you feel the need to feel young again, buy a motorcycle or go bungee jumping, for at least these experiences will have a semi-lasting effect.

-Richelle Eger

References:

American Academy of Dermatology. 2011. Causes of Aging Skin [online]. Available from http://www.skincarephysicians.com/agingskinnet /basicfacts.html [accessed 8 February 2014].

Kafi, R., Kwak, H. R., and Schumacher, W. E. 2007. Improvement of naturally aged skin with vitamin a (retinol). Arch. Derm. 143(5): 606-612.

Thrasybule, L. 2012. The Truth About Anti-Aging Products [online]. Available from http://www.livescience.com/36720-anti-aging-products-lotions- supplements.html [accessed 8 February 2014].

1 Comment

Posted in Biological sciences, Public engagement

Tagged aging, cream, health, skin, wrinkle, young

Animal Vibrissae Inspire Electronic “Whiskers” for Robots

Posted on February 10, 2014 by Julia | 4 comments

If you have been following the news lately, you might have heard about a recent study published in Proceedings of the National Academy of Sciences by scientists from a Laboratory at Berkley University who have been developing electronic whiskers for use in robots.

In this video is a brief overview of the technology from the news:

http://www.dailymotion.com/video/x1a5e83
Video source: newsy videos daily motion

As fascinating as this technology is, you are probably wondering logistically about the inspiration — animal whiskers, or as they are scientifically know, vibrissae. So the question is, how do vibrissae actually work and why are they so important?

Image Source: anniejay on Flickr

If you have a pet cat or dog, you have probably noticed vibrissae protruding from either side of their snout. One might easily dismiss these as decoration, based on the fact the human facial hair is essentially cosmetic. However in the case of many animals, vibrissae are an integral part of how they view and interpret the stimuli of there surroundings.

These highly specialized hairs, also found on carnivores, rats, beavers, seals and bears, are very stiff and are rooted deep under their skin. At its base, there are touch receptor cells, as there are at the base of all ordinary hairs. Only here, they are in much higher concentration. Then since a vibrissa is long and very flexible, it is able to amplify a small touch at its end so as to be felt with high sensitivity.

Image Source: wikimedia commons

It has been suggested by neuropsycologists that the size of a brain region devoted to a particular sense can be correlated to its relative importance in interpreting sensory data. In the case of dogs, 40% of the area of their brain linked to touch is associated with the face and a large proportion of this is then specifically for vibrissae. Interestingly, for each separate vibrassa, it can be shown that it connects to a separate place in the brain of a dog. Therefore vibrissa are an absolutely essential facet of their sensory perception.

Vibrissae are controlled by muscles that move them forward in a “whisking” motion as the animal approaches an object. As they touch a surface they impart information about the texture as well as its location, which can help in the recognition of an object or surface. Their sensitivity is even so great, that they are able to detect changes in air currents. As an animal nears a solid object, his motion pushes air towards the object, of which some is reflected back and picked up by the vibrissae. Thus they are able to determine the location of an object without actually touching it.

Now that you know how vibrissae work, and their importance to animals, you can appreciate how valuable an electronic version would be. If robots could be equipped to interpret sensory information in this way, they could be used to execute tasks which previously would have been impossible.

Julia Brown

4 Comments

Posted in Science in the news

Tagged Animals, Berkley University, Robots, technology

Olympic Fallout: Just How ‘Green’ is 2014?

Posted on February 10, 2014 by gregoryubc | 1 comment

Source: Flickr commons

Last Friday night, the world turned its eyes to a small town on the eastern coast of the Black Sea; the Sochi 2014 Olympics had begun. With opening ceremonies full of winter wonder, and the promise of a brave new world from International Olympic Committee (IOC) President Thomas Bach, Russia ushered in the next iteration of winter competition.

Though mired in controversy regarding the overrun of this Olympics (it is expected to cost roughly 50 billion Euros in total, by comparison Vancouver 2010 cost about 5.5 billion Euros), quietly shuffled aside are the concerns raised over the environmental impact.

Sochi National Park
Source: Flickr commons

To construct the Olympic venue for Sochi 2014, an area encompassing 8,750 acres of wetlands within the Sochi National Park has been effectively demolished. Though this area represents roughly 1.8 % of the total park size, it remains a sizeable portion to be lost. During the bidding process, Russia assured a zero-waste games and promised to follow Green standards. While this looks good on paper, zoologist Suren Gazaryan says “Sochi organizers have failed on all Green promises”. Gazaryan asserts he has witnessed not only illegal dumping of waste material, but also the blocking of major migration routes of animals residing within Sochi National Park; the park itself represents an extremely productive ecological area home to over 65 species of bird, none of which have been seen recently around Sochi.

Bolshoi Ice Palace – 12,000 seat multi-purpose arena
Source: Flickr commons

All of this begs the question: Just how stringent is this concept of Green? It shouldn’t be a surprise that an undertaking of this magnitude will needlessly (as many other locations possess the infrastructure to support international games) require substantial environmental sacrifices. In spite of this, the IOC gave the go ahead to Russia in the face of their fabled ‘no-waste games’ concept. While Russia admittedly maintained their lofty ideal of planting three trees for every one that they cut down during the construction of Sochi 2014, Gazaryan makes the keen observation that “…ecosystems are not Lego sets that you can take apart and rebuild somewhere else”.

For the next two weeks the world will come together to celebrate the best of human triumph, but in the face of glory and prestige have we lost sight of the Green standard we hold ourselves so fervently to? During the opening ceremony, IOC President Thomas Bach implored us all to embrace our diversity; let us not forget that if we are to attain that brave new world, we must also embrace our biodiversity.

1 Comment

Posted in Biological sciences, Issues in science, Science in the news

Tagged Environment, Green, Olympics, Sochi 2014, Sustainability

The Memory Game: Does Caffeine Help?

Posted on February 3, 2014 by madeleinet | 2 comments

It is the night before that dreaded exam; the question surely revolving within your head is whether or not to chug down a cup of coffee. If the goal is not to merely stay awake and finish reading those last few chapters but to keep your optimal level of memory up, then the following information is your key to success.

A variety of beverages contain caffeine, such as energy drinks.
Source: Daniel Jurena, Flickr

The Bad:

Caffeine has a half-life of approximately 6 hours which implies after a full 12 hour day, 25% of the original caffeine dose will still be present in your bloodstream. Depending on dose, varying levels of sleep disruption or insomnia may follow. In addition to not being able to sleep (which certainly will not aid your memory), the side of the coin people often overlook about caffeine is after its intake, as research has shown, the REM (Rapid Eye-Movement) phase and slow-wave deep sleep are affected. REM sleep is believed to be the stage of the regular sleep cycle when memory is consolidated, thus it is critical that it remains undisturbed.

The Good:

Fortunately for coffee drinkers, there is new light shed on the beneficial effects of caffeine. Recently, a study conducted by undergraduate student Daniel Borota and a research team at John Hopkins University marked the first time direct results of caffeine stimulating the improvement of memory were recorded. In the study, participants observed a series of simple everyday images including an office chair, a duck, and a saxophone. To control for variances of individuals’ conditions, all participants viewed the images first, before half of the group was given a 200mg dose of caffeine while the other half was subject to a placebo. The next day, the participants viewed another series of similar images and the group with caffeine intake the previous day was found to identify slight image differences with greater accuracy than the placebo group. This differentiation is called pattern separation in neuroscience and leads to the conclusion that caffeine does indeed enhance memory consolidation in humans.

Dr. Michael Yassa from John Hopkins University further explains the study:

There is a fine line between over-caffeinating yourself to cram for exams and taking a healthy dose of it to help with alertness. This new research shows that perhaps, the recommended amount of caffeine to optimize memory may be 200mg- just about one strong cup of coffee.

Blog post by Madeleine Tsoi

2 Comments

Posted in Biological sciences, Science communication, Science in the news

Tagged caffeine, health, insomnia, memory, sleep

All-Nighters: Not worth it

Posted on February 3, 2014 by brendanguyen | 3 comments

Pulling An All-Nighter
Source: Pink and Black Magazine

I can recall the countless times I have found myself on Facebook, Twitter, Instagram or other social media sites when I should be studying. In wasting all that valuable time procrastinating, I end up pulling an all-nighter in order to complete my assignment. Or that time when I realize that I spent the majority of the term slacking off, so I resort to pulling all-nighters during final exams in attempt to learn all the material. 4 months’ worth of course load in 24 hours…that’s possible, is it not?

Many people believe that all-nighters are necessary to achieve better grades. Is it worth sacrificing a few hours of sleep to attain a higher GPA?

The answer, unfortunately, is no!

The Anatomy of an All-Nighter
Source: Staff Writers, OnlineColleges

Christian Benedict, a professor of Sweden’s Uppsala University in Sweden, and other researchers, performed a study to determine the repercussions of pulling an all-nighter. These sleep researchers analyzed the blood content in fifteen men: after they had a full 8 hours of sleep and after they pulled an all-nighter. After the participants pulled an all-nighter, researchers discovered an increase in the concentration of NSE and S-100B in the participants’ blood. The Swedish researchers compared the effects of sleep deprivation to that of head injuries’ (similar to a blow to the head or from a car accident), since it is known that the molecules NSE and S-100B increase in blood during head injuries.

According to study funded by NINDS (National Institute of Neurological Disorders and Stroke), the brain’s role during sleep is to rid itself of toxins. Lack of sleep may be connected to neurodegenerative disorders, which are result from toxin build-up between brain cells. Examples of neurodegenerative diseases include multiple sclerosis, Parkinson’s and Alzheimer’s.

Not only are all-nighters harmful to brain health, sleep deprivation leads to poor grades! Pamela Thacher, a professor at St. Lawrence University, discovered that students who frequently pulled all-nighters had worse GPAs than students who didn’t. Dr. Philip Alapat, a medical director and professor of Baylor College of Medicine, agrees with Thacher in that a lot of rest helps with memory retention and increases both academic performance and concentration. Alapat recommends that students get 8 hours of sleep, study during the evening (6-8pm), and not abuse caffeinated beverages to increase both health and GPA!

For the students who might disagree and exclaim that they have received a better score when they replaced an hour of sleep with an hour of studying: it is not worth it if it is at the expense of your well-being!

The video below outlines why sleep is necessary for maintaining brain health.

Happy studying!

-(Vy) Brenda Nguyen

3 Comments

Posted in Biological sciences, Issues in science, Science in the news

Tagged academics, all-nighter, brain, college, GPA, insomnia, Neurology, sleep

Oxytocin: The reason for monogamy?

Science behind the Morning Wood

Omega-3: What’s “Fishy” about it?

Gold Medal Physics at the Olympic Games

The Golden Ratio

Anti-wrinkle cream: a bottle full of empty promises?

Animal Vibrissae Inspire Electronic “Whiskers” for Robots

Olympic Fallout: Just How ‘Green’ is 2014?

The Memory Game: Does Caffeine Help?

All-Nighters: Not worth it

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