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Weightless in a “Zero G” Environment?

Chris HadfieldWith Commander Chris Hadfield returning home from the ISS this week, there has been a lot of talk about astronauts getting ”used to gravity” all over again after being “weightless” in a “zero G” environment.  Astronomers and space scientists use these terms in a specific way, and not necessarily the way in which they are used in the popular press.

First – I almost hesitate to mention this because it’s pretty obvious, except that, well, one reads this all the time – it’s just plain wrong to say that there is no gravity in space.  Yes indeed there is gravity in space.  That’s what keeps objects - such as the Moon and spacecraft, for example -  in orbit around planet Earth, that keeps the planets in orbit around the Sun, and that keeps the Sun and other stars in orbit around the centre of our Milky Way galaxy.  If there were no gravitational force in space, all moving objects – such as the Moon, spacecraft, planets, comets, stars, etc. – would move in straight lines according to Newton’s first law of motion: “Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.“  But such objects don’t move in straight lines; they follow curved paths under the combined force of gravity exerted by other objects in their vicinity (Einstein preferred to describe massive bodies as causing a curvature of space, rather than as exerting a “force” that we call gravity, but that’s beyond my little pea brain to comprehend).

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Rainbows: A Truly Spectacular Piece of Art

RainbowBy: Michael Watson, LLB

As we stepped out of the front door at 06.15 this morning, a few raindrops were starting to fall.  The entire sky was aglow with an orange-brown hue.  Turning to the west, we were startled by the dramatic sight of a bright, very colourful rainbow stretching over 100 degrees of sky.

We know that rainbows are caused by the reflection and refraction of light rays from the Sun through circular drops of water that are suspended in or falling through the atmosphere.  The required conditions are (i) early morning or late afternoon, so that the Sun is low in the sky – no more than about 30 degrees elevation above the horizon – (ii) an approaching or departing rainstorm, and (iii) a sharp demarcation between the storm and the sky conditions that precede or follow it, so that there is a clear path between the Sun and the water droplets in the air.

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A Beautiful Study: synthesis of petrol-like biofuel by Escherichia coli

Chloe Nevitt

Escherichia coliPaul Freemont of Imperial College London called it a “beautiful study.” My dad called it a load of “sciencey words.” I call it “innovation.”

John Love from the University of Exeter took DNA from the camphor tree, from soil bacteria and from blue-green algae and spliced them into the DNA of Escherichia coli bacteria. The genetically altered bacteria now were able to convert glucose into fatty acids which they then converted into hydrocarbons chemically identical to those found in gasoline. Since the original material, in this case glucose, comes from a plant source, such fuels are referred to as biofuels.

The reason biofuels are so desirable is because it means using carbon that is already in the atmosphere instead of digging up carbon that has been buried for millions of years (fossil fuels). They present an alternative: a carbon neutral cycle. It is as much a carbon sink as a carbon source. What then, does this ultimately mean?

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FOLLOW DR. KO: AAO x zero but everyone knows that the president is Obama!

Barack ObamaI have always found it bewildering that even the most demented patients, ones who barely know their own name, will be able to tell you that Barak Obama is the President of the United States..

There are a few standard questions we ask our patients in order to assess their mental status. Sometimes patients come in confused, either because they have baseline dementia from old age, are hypoglycemic (low serum glucose or sugar level), have had a stroke, or perhaps are acutely intoxicated with alcohol or drugs. The differential diagnoses for “altered mental status”, which doctors like to shorten to AMS, or confusion, are vast.

First, we want to know if the patient is awake, versus drowsy, or obtunded. Then we qualify the patient’s responsiveness. Is the patient responsive to verbal stimuli? Will they respond to their name? Or do they react only to noxious stimuli, such as inflicting pain by say rubbing their sternum.

Once a patient is responsive, you want to assess their level of orientation. Here come the questions. The quickest way to assess orientation is by asking three simple questions: What is your full name and date of birth?

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Mental Indigestion

Mahmoud AhmadinejadYou have to be careful what you read these days. With the plethora of social media platforms infiltrating our screens (wherever they may be) and the ability to do a simple one-click and get all the information you need, applying a critical eye has never been so – well, critical.

One of the most influential sources of news these days is not that of traditional media sources, but rather those that can be found in the blogosphere. Manufacturers of products depend on bloggers to test and review their products just as much as consumers of such products go to these same bloggers for reviews. But where do these lines get mirky? How do we know where credibility lies and nonsense rears its ugly head? Which sources are legitimate and which are, to say the least, totally full of it?

Let’s take the The Onion, for example, an online daily publication that covers world, national and local issues. Unlike other popular online news sources, The Onion is a satirical news forum, entertaining its readers with a variety of stories poking fun of daily news events, both real and fictional. The Onion has garnered quite the following since its 2007 inception and it is widely known for its work. Following in the steps of its popularity, other satirical news outlets have also sprouted. The problem with this, however, is that these sources are not as widely known and consequently, can be taken totally out of context. (At least initially, until the reader realizes that they’ve basically been “punked.”)

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Hormones: The Good, the bad, and the ugly

hormonesRegina Palamar, 4th year biology
University of Ottawa

Behind every bad mood, sad emotion or untimely face pimple, is a hormone.  Hormones are what Simon Cowell is to the American Idol contestant, what The Joker is to Batman, and what Biff Tannen is to Marty McFly.  Hormones are bullies who always seem to have it in for us.  Nobody likes a bully, but we always forget that they are central characters that play very important roles.  Without Biff Tannen, Marty McFly would never have become a hero, and as much as nobody likes Simon Cowell, he efficiently weeds out the good singers from the ones who should stick to their day jobs.  Similarly, hormones play a critical role in keeping our bodies running smoothly.

Hormones are part of what is called the endocrine system, a complex network of cells that work together to regulate a wide variety of our bodily functions such as our hunger, growth, and reproduction.  When a cell in one part of the body needs to communicate with a cell in another part of the body, it releases a hormone.  This hormone will travel through the bloodstream from one cell to the other, relaying information and stimulating certain types of cellular activity.  It’s kind of like a smoke signal except instead of using smoke from a fire, to communicate a message, the body uses hormones.  For example, when a person gets frightened the cells in the adrenal glands sound the alarm by releasing a hormone called epinephrine which travels to other cells in the body and stimulates the “fight or flight” response.

FOLLOW DR. KO: The Girl with a Lethal Secret

Sometimes, I feel like my life comes straight out of a movie.

Imagine this opening scene: A young woman who appears to be in her late teens to early twenties hails a passing ambulance in the middle of the night, says she has done cocaine for the first time and isn’t feeling well. She then has a seizure and collapses.

The EMS (Emergency Medicine Services) transports her to the closest Emergency Department (ED), which happens to be Lincoln Medical Center where I work. Upon arrival to the ED, the patient had another seizure before going into cardiac arrest. It took the emergency team seven attempts to shock her heart back to a detectable and regular rhythm, after which the now unconscious and intubated (a tube was inserted into her airway and connected to a ventilator to breathe for her) girl was transported up with all her tubes and ventilator to the Medical Intensive Care Unit (MICU) where I was assigned to be one of her doctors.

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YOU ASKED: Can you please comment on the “arsenic in your food” report?

The report by Consumer Reports is a compelling look at the quantities of arsenic found in various types of rice and rice products that they tested. Arsenic is found naturally all over the world in soil. Some plants happen to take up more arsenic than others and that’s how arsenic ends up in certain foods, such as rice. The truth is that arsenic being found in rice is not really something new. In fact, the U.S. Food and Drug Administration (FDA) and U.S. Environmental Protection Agency (EPA) have been monitoring arsenic in rice for over 20 years. The new report by Consumer Reports has got the attention of the FDA and in response they are currently undertaking a wide-scale survey of over 1,000 samples of rice to verify the findings. The most recent FDA statement claims that it is premature for adults and children to modify their diets and completely avoid rice due to potential levels of arsenic.

In terms of feeding your infant rice cereals and rice products, the American Academy of Pediatrics recommends “offering children a variety of foods, including products made from oats and wheat, [to] decrease children’s exposure to arsenic derived from rice”. Should one be concerned?

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