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.

Membrane madness

by Tyler Shendruk

Published: Apr 7

The problem
ONE IMPORTANT STEP in water treatment is filtration. Nobody wants little gritty pieces of dreg or oily bits of gunk in their drinking water. River water is passed through membranes in water treatment plants which block oversized contaminants from going any farther. Making membranes with large surface areas, but with small enough pores (micro- or nanofiltration), is possible by casting polymers into a film. These films are either hydrophilic (water-loving) or hydrophobic (water-hating).
It turns out that most contaminants are oily, hydrophobic gook, and since “the enemy of my enemy is my friend” the contaminants are very likely to bury themselves in the hydrophobic membrane to hide from the water. They can’t get through at first, but eventually contamination degradates the membrane’s performance.
On the other hand, hydrophilic membranes have their own set of problems. The contaminants don’t like the membrane, don’t bury themselves in it, and so degradation is slower. But hydrophilic membranes tend to be significantly weaker than hydrophobic ones, and so will often break during water treatment.

The researcher
Takeshi Matsuura is a chemical engineer at the University of Ottawa who develops modified membranes that can improve the distillation and filtration processes. In particular, he is interested in modifying surfaces using large macromolecules that can be attached to membranes.

The project
Filtration science would really benefit from filters that are strong, and that do not rapidly degrade. Hydrophobic and hydrophilic membranes each have their drawbacks, but by combining them, Matsuura hopes that he can get the best of both worlds.

The key
While other scientists cast a strong hydrophobic membrane, and later modify it by grafting hydrophilic polymers on top to make a protective coating, Matsuura thinks this is too slow (and costly). He mixes the hydrophilic and hydrophobic polymers together in solution and then casts them. As the water evaporates, the polymers naturally separate. Matsuura is left with a single membrane with a strong bottom layer and protective coating on top. In just one step, he gets a surface modified film that has the strength of a hydrophobic filter, but degrades slowly like a hydrophilic filter. That really is the best of both worlds.

Busy bees

by Allan Johnson

Published: Mar 31

The problem
THERE’S AN OLD urban myth that scientists don’t know how bees fly, that their wings can’t beat fast enough to keep the bees in the air. In reality, bees beat their wings 200–300 times a second, courtesy of the most efficient metabolic rate in nature. This ultra-efficient energy use makes them the ideal creature for studying the workhorse of biological systems: the metabolism.
This system breaks down large energy storing molecules via a series of chemical reactions, each assisted by enzymes. This creates ATP, the energy-carrying molecule that provides power to all the other functions in the body. The general pathways of this process are common to all higher organisms, so what’s true for bees is true for the animal kingdom.

The researcher
University of Ottawa professor Charles Darveau studies metabolism from a physiological and evolutionary perspective, using bees as a model organism. By comparing metabolic differences across different species of bees and weighing them with physiological differences, he can identify which changes in the series of reactions that make up bees’ metabolisms are important.

The project
Most people are familiar with the honeybee and bumblebee, but there are over 300 species of bees in Ontario alone. Darveau has a wide array of species to make comparisons. In addition to this cross-species approach, he can also look at variations within a species to examine these changes. The goal is to develop a complete characterization of the metabolic process: which enzymes make key changes, what steps bottleneck the metabolic rate, and what kind of system is most favoured evolutionarily.

The key
Darveau’s research is on the fundamentals of physiological change, but it has a number of immediate consequences. Because bees burn energy so quickly and efficiently, their wing muscles can heat up to 40°C. This allows them to flourish in environments where many other pollinators would be unable to survive, making bees an important part of northern ecosystems. Darveau’s fundamental characterization also allows other researchers to determine which species have metabolisms suited to adapting to different conditions, vital in determining the impact of climate change on fauna.

Experimenting with evolution

by Tyler Shendruk

Published: Mar 16

The problem
LOOK AROUND YOU. The world is brimming with the diversity of life. The great assortment of species is so much a part of our world that we take it for granted. It’s easy to say that diversity results from the theory of evolution and be done with it. But why is there such a wide gamut of life and how does diversification actually unfold? The question isn’t ‘Does evolution happen?’ but rather ‘How does evolution happen?’
When we look back in time we see that evolution has been punctuated by bursts of spectacularly rapid diversification during which many new species suddenly appeared. This process (called adaptive radiation) is very fast compared to the usually steady march of evolution, but it’s still too slow for scientific study.

The researcher
Rees Kassen is the University of Ottawa’s Research Chair in Experimental Evolution. When it comes down to it, Kassen wants to know the answer to a straightforward question: Why are there so many different kinds of living things in the world?

The project
To study the process of biodiversity, Kassen needs to watch evolution take place in his laboratory. He can do this by studying microbes. Since microbes live for only a short time, Kassen can observe changes that occur over generations in only a matter of days. This makes microbes an ideal model for studying adaptive evolution.

The key
When Kassen places colonies of microbes in a beaker of nutrient-rich broth, the colonies choose to live at the centre where there’s the most food. Early on the colony is smooth and round. After a while, resources become scarcer and competition becomes more fierce. Some of the colonies realize that if they stop fighting for control of the centre and move to the fringes they will have an ecological niche all to themselves. And so some colonies fall to the bottom of the beaker where they evolve into brush-shaped colonies. Others rise to the top where they change into very wrinkly colonies.
The new ecosystem offers the microbes opportunities to specialize and to a certain extent determines the form of the diversity. On the other hand, it is competition for resources that drives the specialization. Kassen suspects that these two factors cause adaptive radiation to occur quickly and helps explain why diversification happens in bursts.