Burying nuclear waste

by Tyler Shendruk
Published: Apr 4

The problem

A FIFTH OF the world’s uranium comes from Canada. CANada Deuterium Uranium (CANDU) reactors have been safely running since the 1950s, but nuclear energy is not without its problems. A handful of leaks have occurred, raising questions about waste management.
Storage of nuclear waste is a particularly important question right now as there is a proposal to build up to four new nuclear reactors at the Darlington Nuclear Generating Station on the northwest shore of Lake Ontario.
Plans to ship waste to depositories in the shield are controversial amongst northern communities and many critics are uncomfortable with the idea of transporting nuclear waste over such long distances.

The researcher

Ian Clark is a professor in the Department of Earth Sciences at the U of O who uses the environmental isotopes found in nature to investigate deep crustal water and geochemical and biochemical processes that occurred millions of years ago.
Clark drills for rock samples and then analyzes the water and gases that have been trapped in these rocks for millions of years. He can determine if the groundwater has been totally isolated or if, over millions of years, new water has been slowly moving through the rocks.

The project

Clark uses natural isotopes as a tool but that knowledge is also extremely useful for predicting the outcome of burying nuclear waste. He was asked to be part of a team that would assess a site at Kincardine in southern Ontario, close to both the Darlington and the Bruce Nuclear generating stations.

The key

The Northern Shield may sound like the perfect place to bury nuclear waste, but according to Clark, it’s not. Yes, the igneous rock making up the shield is hard so nuclear waste shouldn’t diffuse through it, but it has fractures. The shield is leaky because faults let water flow quickly from one point to another.
Kincardine is much better according to Clark. He analyzed rock samples from six holes drilled 850 metres down to sedimentary rock—formed from deposited sand and clay at the bottom of ancient oceans—at the Kincardine site. Clark ground up these rocks and baked fistfuls to get about two drops of water, water that had been trapped for some 400 million years. Helium was also trapped in the rocks for more than 260 million years.
As these rocks are very tight and don’t fracture, and the site is very close to Ontario’s fleet of nuclear reactors, Clark believes Kincardine is an ideal environment and much better than any in the shield to bury nuclear waste.

The ice that shapes the Earth

by Allan Johnson

Published: Mar 28

 

The problem 

THE GREENLAND AND Antarctic ice sheets are melting at an accelerating rate, and we’re not sure how that melting is going to change in the future.
Ice sheets are a metre stick for climate change, but measurements of the Greenland ice sheets’ past changes are in disagreement with physical models. In fact, models underestimate the effect rising temperatures will have on ice and sea levels, and things might get even worse.
If we want to avoid stumbling into the future blindly, it’s vital we understand how ice sheets have responded to climate change in the past and how that, in turn, will affect the world in the future.

The researcher

Benoit Lecavalier is a graduate student working with professor Glenn Milne in the departments of physics and earth sciences at the U of O. By using computational modeling, he works on reconstructing the evolution of the Greenland ice sheet from the peak of the last ice age to the present moment using field observations.

The project

By attacking the problem of ice thickness from a geophysical perspective, Lecavalier is able to address the overall system as a set of interlocking feedback loops—when temperatures rise, the ice coverage begins to melt, and the melting ice raises sea levels.
But what’s not so obvious is the ice sheets are so heavy they deform the planet itself. When they melt, the removed weight causes the planet to reshape, making sea levels on the other side of the planet rise even more. The Earth itself behaves like a giant, slow-moving fluid, responding to pressure from the ice.

The key

By considering the physical processes of the Earth’s deformation and subsequent reshaping, it’s possible to take a second look at the history of Greenland’s ice sheet, considering not only sea level, temperature, and past ice extent, but also the fluid response of the Earth.
Considering this additional set of constraints, Lecavalier is able to improve the agreement between the ice model and field observations. This improves our understanding of how ice sheets behaved in the past, which helps us better comprehend their behaviour today and predict their future.
Since there were times in the past when the Earth was this warm, understanding how ice responded then gives geophysicists a chance to glimpse the future today.

Nanoengineering cyborgs

by Tyler Shendruk
Published: Mar 14

The problem

CYBORGS AREN’T SCIENCE fiction. All around us people with pacemakers, insulin pumps, and prosthetic implants continue to live normal lives because of mechanical and electronic parts within their bodies. It’s not sci-fi; it’s mundane.
But that doesn’t mean combining human bodies with technology is scientifically simple. Even relatively straightforward implants need to be biocompatible or human tissues won’t accept them. Implants also need to be reliable.
We may take it for granted, but our bodies are amazingly robust. When we sustain injuries, we heal—but implants don’t. Hip replacements are some of the most successful prosthetics, but even they have a 20 per cent failure rate after 20 years.

The researcher

Amirhossein Ketabchi came to Canada to do his undergraduate degree in engineering at the University of Ottawa. Here he found a tight-knit community of students and decided to stay in Ottawa to continue graduate studies. Ketabchi is now a master’s student in the Surface Nanoengineering Laboratory with an interest in medicine and bio-materials.

The project

Titanium is one of the best bio-materials for implants. It’s light, strong, non-toxic, resistant to corrosion, and isn’t bad at osseointegration—the merging of bone and non-bone into a single object. Not all metals are good at this, but titanium isn’t bad. Ketabchi thinks he can engineer it to be better.

The key

In order to engineer better biocompatibility, Ketabchi modifies the surface of the titanium. Because your body’s cells are in contact with implants, modifications must change nanoscopic details. Ketabchi does this nanoengineering by dipping titanium into an acid mixtures. The acid causes an oxide layer of open nanotubes to form on the surface of the titanium, which human bone can then grow into. Nanoengineering the surface of titanium like this improves its biocompatibility.
But soaking metal in strong acid for hours and hours weakens it, and the last thing you want is a titanium pin in an implant snapping. So Ketabchi knows there has to be a tradeoff between biocompatiblity and preserving strength to withstand years of fatigue. He tests the endurance limit of pin after pin, looking for the perfect compromise between biocompatibility and strength.

Explosive super sensing

by Allan Johnson
Published: Feb 29

The problem

A FEW YEARS ago there was a worldwide hike in food prices because the United States made incentives for making biofuels—gasoline with ethanol, an environmentally friendly alternative to regular gas—attractive. The need for biofuels is clear, but how do we tell if manufacturers are actually making fuel from crops and not just repackaging normal gas and charging double?
Seemingly unrelated, Vancouver sits directly over a relatively quiet fault line—a place where the pieces that make up the Earth’s surface meet. How quiet the fault line actually is, however, is difficult to determine without a history of its past activity.
There is also a need to monitor our nuclear waste, making sure that none of it is being spread from secure storage.
The solution to all these problems lays within tiny quantities of telltale radioactive isotopes that give the necessary history. How can the history of a few atoms within an isotope be detected to solve all of the above and similar problems?

The researcher

Liam Kieser is an associate professor of physics at the University of Ottawa and the director of the IsoTrace Laboratory in Toronto. He works on using accelerator mass spectrometry (AMS) to reach unparalleled levels of sensitivity, finding the smallest traces of isotopes that would be undetectable normally.

The project

AMS uses a particle accelerator to bombard a sample with fast-moving particles, freeing and ionizing them. Imagine billiard balls hit with a wrecking ball. The atoms in the sample shoot out, guided by electric and magnetic fields. Different masses move differently in the field and researchers can pick out the particles of interest by their mass.
Thanks to the high energy projected from the mass spectrometer, molecules that might have the same mass as the isotope in question explode into fragments, which no longer have the same mass. On the other hand, the isotopes come out with so much energy that techniques from particle physics can be used to detect them down to the single atom level. Altogether, AMS can detect the presence of an isotope down to a millionth of a billionth of a gram.

The key

Kieser works on ways of further increasing the sensitivity of AMS, devising methods of separating not just isotopes from molecules of the same mass, but isotopes from other atoms with the same mass. While molecules can be split easily, the other atoms are effectively indestructible.
Recently he’s developed a method for separating Sulphur 36 from the radioisotope Chlorine 36. Chlorine 36 is of great interest in ground water studies, since a great deal was generated during nuclear testing in the 1950s. Upon completion of the Centre for Advanced Photonics and Environmental Analysis at U of O, Canada’s only accelerated mass spectrometer will move to Ottawa in a new state of the art lab, providing the tools for extreme sensing.

Crammed in the capillaries

by Tyler Shendruk
Published: Feb 9

The problem

DO YOU EVER stop to think about your cells’ needs? Every one of the trillions of cells making up your body requires energy and is fed by blood. Armies of red blood cells continually parade through the heart, to the furthest backwaters of your body, and back again.
To get to every part of your body, the capillaries that conduct these nutrient-carrying cells to their destinations must be tiny. Blood cells are forced to march single file through severely confining micro-veins. In fact, the blood cells are actually 25 per cent larger than the smallest capillaries they travel through. How can this be?

The researcher

Alison Harman is a graduate student in the Department of Physics at the University of Ottawa. As a physicist, she is more interested in the mechanics of cells than anything else. She doesn’t worry about the fact that the cell is alive. Instead, Harman uses simplified computer models to simulate the physical properties of cells.
These virtual cells are still complicated, but they are simple enough that Harman can extract information about cellular membranes without worrying about the intricacies of life.

The project

Harman models the blood cells, simulating each of the lipids that make up the cell membrane, but not the contents of the cell. Each of the lipid molecules are made up of a head that likes water and a tail that avoids water.
To keep everyone happy, the lipids organize themselves into a bi-layer with tails facing in and heads facing out, which results in an empty vesicle.

The key

Vesicles are most comfortable as spheres, but they are very deformable. When they are carried through fairly large capillaries, the flow pulls them out into a flat, parachute-like shape. Faster flow stretches the vesicle longer.
Harman’s simulations show this stretching happens at the edges of the parachute. At very high flow rates—about 100 times faster than blood actually flows in the body—the vesicles eventually break.
Harman sees a different picture in the smallest capillaries. The vesicles are so crammed they must fill the entire tube of the capillary and deform into a pill-like shape. As the flow rate increases, vesicles stretch until they can’t stretch anymore. They usually break along their side where the membrane is closest to the wall, fitting into the capillaries.

Troubles with texting

by Allan Johnson
Published: Jan 25

The problem

LOOK AT THIS article. Now at your phone. Now back to this article. Chances are, you have plenty of text messages saying something like, “OMG, ttyl, g2g”—or at least that’s what some people might expect.
Expectations aside, there isn’t much scientific knowledge surrounding texting habits. Texting is private, and finding information about how texts are created is much more complicated.

The researchers

Elizabeth Marshman, assistant professor at the University of Ottawa’s School of Translation and Interpretation, and Lynne Bowker, chair of the School of Information Studies at the U of O, are trying to separate fact from fiction when it comes to texting.

The project

Marshman and Bowker head the Ottawa branch of text4science, a collaboration of Canadian researchers building a data set of text messages and demographic information about texters for scientific study.
Research volunteers provide information about their texting habits, language usage, and aspects of their day-to-day communications—with personal information kept confidential—and then forward their text messages to text4science. The goal is for the project to gather 100,000 text messages, and combine the data obtained in Canada with findings from similar projects in Europe.

The future

According to Marshman, “One of the things that’s really interesting … is that we don’t know what we’re going to find.” This research is considered exploratory  because so little is known about texting.
The researchers hope results will show how people compress ideas into texts. They’ll also look into how French and English mix in texting and what kind of variation there is in abbreviations used. Is “c u l8tr” a universal choice, or is there more creativity involved in conveying the phrase?
Bowker also hopes the data will lead to automatic translation mechanisms for text messages, allowing texters to stay in the loop without struggling to read through a mess of unfamiliar abbreviations.
If you’re interested in participating in the study by donating your text messages, visit Text4science.ca Participants are eligible for weekly prize draws.

LEED at the University of Ottawa

by Tyler Shendruk
Published: Jan 11
as an inset to Christopher Radojewski's
Social sciences under one roof

THE LEADERSHIP IN Energy and Environmental Design (LEED) is a rating system for judging green construction projects. Buildings are given a total of 100 possible points assessing the sustainability of the chosen site, water efficiency, energy and atmosphere impact, materials and resources used, quality of indoor environment, and 10 bonus points for innovative design and regional priority.

The number of achieved points gives the structure a grade:
Certified: 40–49
Silver: 50–59
Gold 60–79
Platinum: 79+

In 2008, the University of Ottawa’s Campus Sustainability Office pledged all new and retrofitted buildings would achieve Silver rating or higher.

What makes it green?

Green wall (also called a living wall).
One huge wall of the atrium will be entirely covered with vegetation and act as a natural air filter.

Heat recovery ventilation system 

Even with the green wall, some ventilation is needed, but exchanging warm indoor air with cold outdoor air (or vice versa) is a waste of energy. By processing the air before it leaves or enters the building, the ventilation system will keep 90 per cent of its heat.

Green roofs 

Three of the roofs will be covered in growth. This follows a strong tradition: The Colonel By building, built 40 years ago, was one of the first green roofs on a Canadian campus.

Data furnace 

The tower is designed to receive 80 per cent of its heat from local campus computers.

Natural light 

Only five per cent of the tower will require lighting. The rest will be naturally lit.

Cellular scaffolding

by Tyler  Shendruk
Published: Nov 30

The problem

EVERY CELL THAT makes up our body carries genetic information needed to create a human being. Before birth, those cells become specialized—some cells are blood cells, some are kidney cells, some are neurons, and some are stem cells that have the freedom to become any cell the body needs.
Cellular signalling summons stem cells to injuries, but doesn’t completely control the type of cell they turn into. The local environment plays a part in the process, deciding what the stem cells will become. Temperature, acidity, and material properties of the injury are essential to the stem cells. They will act differently whether the site is stiff, elastic, or immersed in a bodily fluid. Adding to the complexity, unless it’s blood or bone, our body’s contents are not pure solid or liquid—they’re something in-between, like jello or honey.

The researcher

Shane Scott, a master’s student in the physics department at the Univeristy of Ottawa, studies the properties of these complex fluids. He is a rheologist—he studies materials that both stretch and flow, like gels or molasses.

The project

To make stem cells in a lab, you grow them in protein gel. This gel can mimic the properties of different parts of the body. The gel is easy to tweak, and scientists like Scott can add binding domains that act like docking bays for cells to attach to, making them perfect cellular scaffolds.
The behaviour of those cells depends on the rheological properties of the gel, making it necessary to categorize the gel before you start growing cells.
Scott’s proteins are random coils with a helix cap at both ends, which means when he mixes these proteins into a solution, the coils tangle together and form a gel. If he wants a more permanent gel, Scott chemically links the proteins into a network.

The key

Scott characterized protein gels that were part physically tangled and part chemically linked for different temperatures, acidity, and concentrations. Scott showed when a binding domain was added to the gel to turn it into a cellular scaffold, the rheological properties didn’t change, meaning biologists don’t have to worry about stem cells behaving differently because making a protein gel into a cellular scaffold altered their environment.

Staring at the sun

by Allan Johnson
Published: Nov 16

The problem

THE WORLD IS in need of green energy solutions. Wind, solar, and geothermal are some of the energy-gathering meth- ods capturing researchers’ imaginations as alternative energy sources. Harnessing power from nature depends on geographic location. Solar is the best bet for Spain, while wind might be better for stormy Scotland. So, what type of power should Canada be using?

The researcher

Aaron Muron is an engineering student at the University of Ottawa SUNLab trying to figure out how advanced solar systems can work on campus. His work sits on the Sports Complex rooftop, tracking the sun.

The project

We can see the sun dim when a cloud passes over it, but there’s little data on how this impacts solar energy. Most simulations available are designed for a “standard atmosphere,” which might not accurately describe the climate in Canada.
To get a better sense of Ottawa’s and, subsequently, Canada’s climate, Mu- ron and his associates assembled a solar tracker with various types of solar cells. The cells include ultra-high efficiency triple junction cells that follow the sun throughout the day, generating power. The outputs of the various cells are constantly recorded and sent back to the lab for analysis.

The key

The tracker was also fitted with a spectrometer and a camera that point directly at the sun. This allows the SUNLab team to match changes in the computer systems to changes in the sun’s intensity and spectrum, com- paring them to weather conditions.
Different types of cloud cover have different effects on the sun’s light and can be dealt with differently—low-lying clouds tend to block most of the light while higher, thinner clouds just distort it.
With new information about how the climate changes the sun’s light, researchers can assess how solar energy will fit into Ottawa’s, and Canada’s, future.

Survival of the same

by Tyler Shendruk
Published: Nov 2

The problem

NATURAL SELECTION IS one of the cornerstones of modern science. Genetic mutations cause organisms to be more or less fit to survive; those who can’t compete die, while the strong pass on their genetic strengths to a new generation.
Still, genomes are complicated things. Genes can react to internal and external stimulus by changing the type and amount of proteins expressed at any given time. This allows species to respond to new situations faster than if they had to evolve over many generations.

The researcher

Daniel Charlebois is a PhD student in the physics department at the University of Ottawa who conducts research out of the Ottawa Institute of Systems Biology. A physicist studying biology may be a surprise to some, but Charlebois has an undergraduate degree in biology and his training in physics brings with it an extensive knowledge of non-linear systems and computation, which help him to understand gene expression.

The project

Charlebois wanted to look at the potential survival mechanisms besides genetic mutations. Clones all have the exact same genes, but natural variations in the local environment of each cell cause different genes to be expressed in each individual. This “noise” means even a population of genetically identical clones has some natural diversity.

The key


Charlebois simulated a community of clones, which he subjected to a harmful drug. He didn’t let the virtual-reality cells evolve through mutations. Because the cells couldn’t evolve and had no specialized defence against the drug, traditional evolution theory would say they could never develop any drug resistance and would all die—but that’s not what Charlebois saw.
Instead of all dying, a small amount of cells lived through the attack, because at the time they expressed the exact protein mix needed to survive by chance. The generations, which grew out of this small community, were genetically identical to the clones. No mutation or evolution had taken place, despite survival of the fittest occurring.
Genetic noise isn’t always something annoying to be rid of. Charlebois believes natural fluctuations are a survival mechanism life takes advantage of for adaptation without mutation.

Play on—nom, nom, nom

by Tyler Shendruk
Published:  Nov 2

Illustration by Devin Beauregard

    

New study shows correlation between video games and weight gain

Chaput and his collaborators invited 22 healthy, normal-weight boys between ages 15 and 19 into the lab. The night before the experiment, the boys were instructed not to eat. They arrived at 7:30 a.m. and were all given the exact same breakfast. At 10:30 a.m., they started playing the soccer game FIFA 09 on an Xbox 360 for one hour. Chaput then gave the participants a huge spaghetti lunch. The leftovers were weighed so that researchers could know how much they ate.

The boys usually ate more after gaming. In fact, they ate an average of 163 calories more. This may not sound like much compared to Health Canada’s recommendation of 2,450 calories daily, but these extra calories can have a long-term impact according to Chaput.

“Weight gain is just a small but chronic energy gap over time. Even a surplus of 50 calories per day on a chronic basis can lead to 10 kilograms of weight gain over 25 years,” he explains.

Chaput also wanted to know why boys eat more, so he took blood samples while they gamed. The samples told Chaput heart rates and blood pressure had gone up, but none of the hormones that trigger hunger were found in the work up.

“It seems that it’s more eating in the absence of hunger. Participants don’t feel [hungrier], but they eat more,” says Chaput.

“It’s not explained by the hormones that trigger hunger, so we think that it’s more related to the mental stress aspect of video gaming.”

Chaput’s findings are less than they would be in an outside setting because his subjects played alone, while kids tend to play with friends and usually eat more with others. Chaput also didn’t allow any eating during gaming and the boys played for only an hour.

Chaput also looked at males for a couple of reasons: First, they didn’t want to complicate things by having physical gender differences and “because there are more boys than girls playing video games,” says Chaput.
“Although I would like to know if it’s the same thing with girls,” he adds.
What are the next steps for Chaput’s research? Besides studying adults and interactive gaming, Chaput’s says his study is a warning and direct action is needed.

“Do we find this same pattern in adults? We don’t know … The next step is with active video gaming,” says Chaput. “Of course, we burn more calories when we’re playing this active gaming … but none of those studies have assessed energy intake.”

Chaput adds, “We need to have a better balance between physical work and mental work. We’re doing too much screen time and not enough physical activity.”

Demystifying tradition

by Allan Johnson
Published: Oct 10

The problem

THOUGH TRADITIONAL MEDICINE has been around for thousands of years, only recently has modern science started showing interest in the craft. In the past, peoples, such as the Maya and Native Americans, practiced herbal medicine and developed an extensive knowledge of their environment.
Today, many traditional healers wish to have their methods validated. Their wide expertise on vegetation and medicinal plant properties could provide modern medicine with new pharmaceuticals and a greater appreciation for biodiversity.

The researcher

John Arnason is a professor of biology at the University of Ottawa. His work focuses on ethnopharmacology, which studies the medicinal properties of plants. Like traditional healers, he seeks to validate folk medicine and better understand the role it can play today.

The project

Arnason was invited to Central America by Maya healers to collect plants believed to have medicinal properties. Back in Ottawa, the plants were grown and examined for active compounds, which can be recognized by their similarities to well-known drugs. These plants were then tested on animals in collaboration with the Royal Ottawa Hospital.

The key

Arnason’s team was shown over 70 active and previously unknown plants by the Mayan healers, many of them used for psychiatric purposes. The team applied this knowledge to identifying avenues for further research.
The results clearly show the strength of traditional medicine. The traditional beliefs are grounded; natural medicines can work. The breadth of plant life uncovered shows the value of biodiversity.
“Working with native healers is wonderful because they have a cosmocentric world view,” said Arnason, “I think the world needs a little more ecological vision right now.”

Liquid crystals can be radical

by Tyler Shendruk
Published: Oct 5

The problem

HEY, SCIENCE! WHY haven’t you built me an iPod the size of a single cell yet? I’m waiting.
Currently electronics are built out of bulk materials and have inherent size limitations: A wire can only be carved so small if it’s made from an everyday chunk of copper. But imagine if electronic components could be made from large molecules or organics instead of bulky metals.
One day, organic components might be smaller, cheaper, and even easier to fabricate than traditional wires. Sure, it sounds like a great idea, but is it possible?

The researcher

Alicea Leitch doesn’t know either, but she’s trying to find out. Leitch is a post-doctoral researcher in the chemistry department at the University of Ottawa who likes to work on projects that have concrete applications.
Before she arrived at the University of Ottawa, Leitch had already started working on highly reactive chemical substances called radicals.

The project

Radicals can be extremely reactive because they have an unpaired electron, which is just dying to find its soulmate. It’s not exactly picky—radicals will react with just about anything. However, when they are stabilized, the unpaired electron can become very valuable. Sometimes radicals can help carry charges, making otherwise non-conductive materials more interesting.
This makes radicals tempting for molecular electronics. Unfortunately, chemical stabilization almost always vetoes the properties of interest.

The key

To control the radicals without loosing the conductivity, Leitch doesn’t bother with chemical stabilization. Instead, she attaches the radicals to microscopic discs so the previously troublesome unpaired electron doesn’t belong to a single atom. It becomes shared between all the atoms that make up the disc, making it less reactive but still conductive.
On top of that, using discs has unexpected bonuses: They float in liquid and they like to stack in an orderly fashion, like a crystal. This makes them a liquid crystal. If Leitch can get the liquid crystals just right, the discs will automatically assemble into tiny chains.
This natural stacking is great because the structure of molecular electronic components plays a really important role, but is usually hard to control. Because they are stacked together, the single electron can jump from plate to plate, and eventually make its way from one end of the chain to the other.
Together, the conductivity of the unpaired electron and the discs’ self-assembly into long, flexible chains could make Leitch’s liquid crystals into pretty radical wires.

Why we woo

by Allan Johnson
Published: Sept 21
 

The problem

THE LONG, COLOURFUL tails on peacocks; the loud, distinctive cry of birds; the useless eye-stalks of some flies: All these traits are found in nature, even though all of them make the bearer an easier target for its enemies. But still, these traits are passed on through generations, making researchers wonder about their purpose.
Evolution is full of species that have naturally selected—and potentially dangerous—physical traits. Female peacocks, for example, prefer males with large and colourful tails, even though they make them easier for predators to spot.
A question arises: Why and how do animals choose their mates (something scientists refer to as sexual selection), and how does this selection affect the species? Does it hasten the removal of harmful genes, or does it promote diversity and speed up the development of the species?

The researcher

University of Ottawa biology professor Howard Rundle looks for logic behind sexual selection. Evolution happens at a different rate for different species, based on how long each generation lives and breeds. By using fruit flies for testing, with their short life cycle, he tracks evolutionary changes in populations in years instead of millennia, allowing him to watch evolution as it happens.

The project

Rundle set up many populations of flies and controlled for how they mate. For each population, he allowed some groups of flies to pick their mates themselves, while others were forced to select mates at random rather than according to their normal preferences.
After data from several generations was analyzed, it became clear how genes harmful to the flies were passed on. The answer surprised the researchers.
In theory, if sexual selection allows for harmful genes to be bred out faster than random mating, you’d expect less of those harmful genes in the flies allowed to mate selectively. Instead, Rundle found there were no differences between populations, and for a few genes, there were less copies of the harmful genes in the randomly mated population—completely the opposite of what you’d expect.

The key

With further analysis, the reason for the contradiction became apparent. While female and male flies both chose mates without the harmful genes, there were unforeseen consequences.
When males breed with healthy females, they inject the latter with proteins that put their reproductive systems into overdrive. This brings down their fitness compared to the females carrying the defective genes, hurting the healthy females in the long run.
This problem in studies of sexual selection has long been abundant with theories and absent in data. Experimental biology is finally catching up to

Chemistry as art

by Tyler Shendruk
Published: Sept 9

The problem

UNLIKE MEDIEVAL ALCHEMISTS, who only dreamt of turning lead to gold, modern chemists are experts at reshaping matter. They can produce many molecules, but the process is often wasteful and time consuming. On the other hand, Mother Nature is much more efficient at the task, proving that chemists still have a lot to learn.
Biological processes use enzymes to create specific chemical reactions with little waste and extreme precision. When compounds react to form new chemicals, they must overcome an interaction barrier keeping them separate substances. Enzymes are the tools that these systems use to lower interaction barriers so that a reaction can occur, and new compounds can be created. Enzymes accomplish this by temporarily tethering the reactants together and orienting them so that they approach each other in the best possible way, rather than just randomly reacting.

The researcher

Melissa Macdonald is a PhD candidate in André M. Beauchemin’s lab at the U of O, who knows that if chemists can learn to control and create their own enzymes, many reactions could be recreated more efficiently. In Macdonald’s eyes, chemistry can be an elegant art and not just a series of random reactions.

The project

One reaction in particular stands out for Macdonald: Worthless alkynes can become valuable amines by adding a nitrogen-hydrogen bond. Since amines are a common active ingredient in pharmaceuticals, it is shocking that this seemingly simple transformation is so difficult to reproduce. The usual process involves heating the reactants to extremely high temperatures and using metallic catalysts to lower the interaction barrier. It’s exactly the sort of problem that requires a more elegant, artistic strategy.

The key

By designing an organic catalyst that uses the same tethering method as enzymes, Macdonald tackled this notoriously difficult transformation. The tethering molecule directed the approach of the reactants so intelligently that the interaction barrier was reduced and the reaction could occur at room temperature without the help of toxic metal catalysts.