Nano-worries

The Council of Canadian Academies has written a report for the Canadian federal government recommending greater regulation on the use of nanomaterials in consumer products. Their reasoning being that a chemical compound, when incorporated into a nanoparticle will oftentimes display different properties than when it exists in its other forms.

I do not have a problem with the recommendations of the report as listed in the article. The whole purpose of developing nanoparticles is to create a material with different chemical properties than would be observed if the compound were simply a bulk solid or in solution. Therefore treating each nanoparticle as a separate chemical entity that needs an individual assesment of its environmental and toxicological effects only makes sense.

However, I can’t help but detect a bit of nano-hysteria in the article itself. The author seems to be suggesting that there is a danger posed by nanoparticles because of the fact that they are so small, which is a gross over-simplification.

Sure, nano is small, but it is quite large on the molecular scale. In terms of size, nanoparticles are more comparable to proteins or polymers, which are much larger than many of the individual chemical species found in your blood like sugar, caffeine, nicotine, ethanol, vitamins, minerals, hormones, etc.

It may be that titanium oxide nanoparticles found in sunscreen are more likely to enter your system perhaps than the bulk form found in house paint, especially when the former is applied directly to your skin and the latter, typically, is not. However, it’s rarely the solid form of a chemical that we’re concerned about. The problem with lead pipes isn’t that you’re likely to absorb lead into your system by simply touching them, it’s that water-soluble, oxidized forms of lead enter your body by means of the water the lead pipes are transporting. Water-soluble, oxidized forms that are smaller than any nanoparticle.

What needed to be stressed in this article is that there can be substantial differences in the chemical properties of compounds when alone or incorporated into a nanomaterial. Instead, it is suggested those differences are simply related to nanoparticles being so darn small.

They even mention drug delivery in the article, which is where multiple molecules of the drug are incorporated into a single nanoparticle. The goal is to achieve timed release of the drug from the nanoparticle structure to maintain a more consistent concentration of the drug in the blood stream as opposed to taking a pill of the bulk solid form which, after ingestion, results in a significant spike in the blood concentration of the drug. The chemical properties of the drug do not change, and the difference in how the drug is introduced into the blood stream is in no way related to the difference in size between a single nanoparticle and a drug tablet.

The field of nanoparticles is varied and complex, in some cases the difference in size may be a critical factor in the different properties of the materials while in other cases size may play little to no role at all. This is point where journalism and science commonly clash. Journalists aim for accuracy, yet when writing about science look for a simple, generalized way to present the concept to their readers. Science, however, in its own quest for accuracy, can rarely comply.

Kids’ Brains

I found a recent study that suggests that children’s brains are programmed to elicit empathy upon seeing someone get hurt, accidentally or intentionally.  The researchers performed MRI scans on 17 children while showing them an animation of people getting hurt.  They found the same areas of the brain that light up in the adult brain were also activated in the children studied, including the area responsible for moral reasoning.

It is an interesting finding, but perhaps not that surprising.  I think anyone who’s worked with a large number of children believes not only that children are capable of empathy, but also most kids, regardless of their upbringing, are inherently good and decent people.   At least in the age range of the children of this study, who were between 7 and 12 years old.

However, therein lies the problem with this study’s main conclusion, in my view.  The researchers are suggesting empathy is hardwired, not taught, but they didn’t study any children of the age when you would be teaching them about empathy.  In a daycare, the three-year-old who hits their playmate is made aware of the fact that they’ve hurt their friend and asked how they would feel if their friend hit them.   Is that not teaching empathy?

It’s a good question as to whether the child is capable of responding to such reasoning because their brain is programmed to do so, or whether scolding the child in this manner is actually creating the wiring that will allow the child to respond empathetically later in life.  A question this study, unfortunately, does not address.

All we need now is evidence of Mothra

Researchers have uncovered evidence of a giant sea scorpion; a fossilized claw that is so large, the creature that it belonged to would’ve been 2 metres long–longer than humans are tall.  The fossil record has provided evidence of other super-sized bugs, but this new scorpion would be the biggest found to date. 

It’s believed it lived about 400 million years ago, along with other really large arachnids and insects; organisms that died out in an epic evolutionary struggle with armoured fish.  At least, that’s what the paleontologists say. 

The timing of this discovery is a bit coincidental for me, personally, as I have just finished reading Dan Brown’s Deception Point.  So, an article about giant sea bugs immediately caught my attention.  And if you don’t know what I’m talking about, here’s the first (and probably only) book recommendation to appear on this blog:  Read Deception Point by Dan Brown, it’s good.

I hope John Tory reads this

It seems our understanding about how evolution can occur is changing.  Work published in the prestigious Proceedings of the National Academy of the Sciences (PNAS, tee-hee) has found evidence of sympatric speciation; the separation of a population into different species without the need of a physical, geographic barrier.  

The researchers, led by Canadian scientists at Queen’s University, have found that within five colonies of tropical birds living in the archipelagos where there are two populations with distinct breeding seasons, there is significant genetic variation between the populations and, in two of the colonies they have stopped exchanging genes entirely.  The data the researchers collected indicates at least four of these populations have arisen simply out of the difference in breeding periods. 

Darwin had initially proposed that sympatric speciation could occur, and now here’s the evidence.  Researcher Andrea Smith said “that it’s challenging the idea that you need a geographic barrier for species to arrive.”

It’s a good example of how a scientific theory, such as evolution, can be refined when new evidence is found.   

Highlight Reel

No one story has been sufficient inspiration for me to dedicate to it an entire post, however there were a few interesting stories I noticed recently.

In a recent post I mentioned how researchers are looking into clays used as ancient remedies for potential treatments of drug-resistant bacteria.  Well, this recent health alert in Ontario suggesting physicians be on the look-out for a particular sub-strain of Streptococcus pneumoniae 19A provides an example of why this work could be very valuable.  These bacteria commonly cause ear, chest and throat infections which can be readily treated with antibiotics, however this newly identified sub-strain cannot. 

In another post, I discussed research into pheromones, where attraction is (at least, partially) controlled by the sense of smell.  Well, here’s more evidence odours can have a direct affect on behaviour.  Japanese researchers have found a smell receptor in mice that detects the odour of cats and causes the mice to run away, naturally.  It was found that mice who had this receptor turned off would not fear cats, and in fact, they would play with kittens.  To demonstrate the importance of this particular receptor, mice were engineered to have a very poor sense of smell.  While these mice had difficulty detecting the odour of cats, once they did, their response was to flee.  The researchers say this points out there are two distinct functional modules of the olfactory system, one for innate responses to odours and one for learned, associative responses.

Finally, in February of this year researchers investigating if there’s a genetic factor behind type II diabetes stumbled upon a gene called FTO that is related to obesity.  However, at the time that’s all they could say–if you have two copies of a particular variant of the FTO-gene you were on average 3 kg heavier.  The challenge was then to find out how this gene worked and there have been a couple of recent discoveries working towards this end. 

In research involving mice, it has been found that the protein this gene codes for, the FTO-protein, would accumulate in the hypothalamus in the brain.  However, up to 60% less of this protein was found in the hypothalamus’ of mice who were underfed when compared to mice on a regular feeding schedule, suggesting the function of the gene may be related to appetite. 

In separate work, scientists examined the structure of the FTO-protein finding it is very similar to other known DNA demethylase enzymes; enzymes that repair altered DNA by removing a chemical moiety known as a methyl group.  The question of how demethylating DNA plays a role in obesity is still open, but it’s a crucial first step in determining how this gene and its related protein function.

While I am interested in how this gene actually works, I’m just glad there’s another reason why I can claim I’m at least 3 kg heavier than I should be, aside from the amount of time I spend sitting on my butt in front of a computer doing things like writing on my blog.

Critiquing the communication of science

I wanted to write about research from my alma mater; research examining links between brain function and memory.  I was excited when I first found this press release from the communications staff at The University of Western Ontario announcing that UWO researchers will have their work published in the Proceedings of the National Academy of Sciences (PNAS, he, he… get it?). 

But, I don’t have a good grasp of what the research actually demonstrates, at least not from the press release.  Consider that the writer chose this quote from Professor Kohler to help explain to readers what his research has found:

“Recognition based on familiarity can be contrasted with recognition when we spontaneously conjure up details about the episode in which we encountered the person before, such as where we met the person before and when it happened.”

I can’t think of a more obtuse way of saying memories of a person come from a different place in the brain than the memories of meeting them.  Is my paraphrasing an oversimplification?  Maybe, but the details that are omitted for simplicity aren’t as important as your central message, which otherwise gets lost in the pursuit of accuracy. 

I’d be happy if anyone could provide a clearer statement of what these fellows’ research actually entails.  I could ask them myself, but I’m not sure Dr. Kohler would be of much assistance. 

Clay cures

Antibiotic resistance in bacteria is becoming a serious problem.  Over-prescription and improper use of antibiotic drugs is one culprit, though pumping all our livestock full of them may have a role to play as well.  New ways to tackle difficult to treat infections are coming from surprising sources; scientists are investigating to French clays that were used as remedies for infections and ulcers long ago to identify what makes them effective in battling bacteria.  Since we don’t seem to be curbing our over-dependence on antibiotics, it’s as good an idea as any. 

Gay Worms!

The title just about says it all, doesn’t it?  Researchers have been studying microscopic soil worms known as nematodes and have found that through genetic modification they can alter the attraction behaviour of these worms.  In this case, they can apparently get hermaphrodite worms to seek out other hermaphrodite worms, and this doesn’t occur naturally since they reproduce asexually.

Clearly, it’s a loaded topic; if the sexual orientation of one organism is genetically determined, what does that mean for other organisms?  While in the article lead researcher, Erik Jorgensen, says the results are limited to these worms, he is quoted in the very next paragraph suggesting it might be a common mechanism for sexual orientation that could have been carried over through evolution to more advanced creatures. 

I think there’s a good chance there’s a genetic basis for homosexuality in humans, but the argument that if it is so in nematodes, it could be so for humans is weak.  The real potential for this research lies in where these findings lead researchers investigating the sexual orientation in all sorts of animals in the future.     

Research on the cutting edge

As a young boy, I watched many cartoons where good characters fought evil characters.  Roughly three quarters of any given episode would involve characters shooting at one another, but they didn’t shoot bullets; they shot laser beams.  Red and blue blasts of light making all manner of things blow up, but never actually killing anyone; these cartoons supplied me my first impression of lasers.  Ever since, I have considered pretty much anything to do with lasers to be incredibly cool.

So you can imagine how intrigued I was by this study examining how lasers actually work to cut human flesh.  Lasers are now widely used in different surgical procedures, but there was a lack of understanding of how the lasers actually managed to cut into flesh.  Turns out, there are two mechanisms, depending on the type of laser used. 

For longer wavelength, lower energy infrared lasers, they work by actually burning the body’s cells.  The intense heat from the laser causes chemical bonds in the cells to rupture, destroying the integrity of the cell.  It also has the added benefit of simultaneously cauterizing the wound.

Shorter wavelength, higher energy lasers work by causing micro-explosions that break molecules apart, leading to cell degradation.  Each laser pulse creates an electrically charged gas called plasma that collapses at the end of the pulse and the energy released causes a micro-explosion.

This study does more than answer a question that has undoubtedly vexed many a science fiction nerd.  Knowing how different lasers work will help determine which type will work best, depending on the procedure and what part of the body the surgeons are working on.  

However, despite providing valuable insights into laser surgery, I have my suspicions the genesis of this research was originally inspired by something other than the practicality of the knowledge to be gained.   

Fueling the anti-climate change fire?

One of the arguments people use to deny the threat of climate change is to point out that computer models are used to generate predictions of the effects of increasing greenhouse gas emissions and rising temperatures. 

“Models are flawed,” they argue, “we shouldn’t develop policies now to avoid the consequences of climate change when we only have computers providing predictions with high uncertainty telling us what those consequences might be.”

Unfortunately, a recent study seems, at first glance, to support this argument.  Computer models are inherently limited in how well they can predict the consequences if rising greenhouse gas emissions result in extreme increases in temperature, it says.  Most models predict moderate changes in temperature, and there is greater consensus on how the climate will respond.  But, the greater the predicted increase in temperature the greater the variance in the models’ results. 

However, the authors of the study point out that since our ability to precisely predict how the climate will react if specific levels of greenhouse gases in the atmosphere are reached, policies should be linked to temperature targets, not emissions levels.

It could be a dangerous argument to make; the results could easily be spun to argue the predicted consequences of climate change are too uncertain for us to be alarmed.  I’m not certain the momentum in public support for measures to offset climate change can be maintained if people aren’t convinced the results of doing nothing will be bad–very bad. 

Getting people in the Western world to make the necessary lifestyle changes to mitigate or offset climate change is a tall order.  Here, in London, Ontario, there was a big stink because a roadway recently re-named to commemorate war veterans was strewn with garbage.  We can’t even stop people from throwing garbage out the window of their cars!    The tearful Native American man of the infamous commercial would be inconsolable now.

 

It’s a clear sign you need a really solid argument if you want people to consider an alternative to driving themselves everywhere, let alone any other actions needed to curb emissions. 

On top of that, there’s also a call from people truly concerned about climate change to abandon the Kyoto protocol.  They don’t have to argue that it’s a failed policy; I think most people can see not much has been achieved in battling emissions.  In fact,  levels of atmospheric greenhouse gases are accelerating.  But, they make a very strong case the real problem with Kyoto is it’s the wrong tool for fixing the problem. 

As they point out, the greatest obstacle to moving away from Kyoto is it’ll be a huge political challenge for anyone who endorsed it to now suggest an alternative approach is necessary. Especially since non-signatory nations like the U.S. have already used the “alternative approach” terminology as code for a plan to doing nothing. 

However, I think it’s a worthwhile read for anyone concerned about climate change.  If enough people get the word out about their suggested alternative to Kyoto, who knows,  maybe it could motivate people to push for more localized strategies to reduce emissions?