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Stars of polymer science gather at KTH

Bones do a good job of repairing themselves, except when they can’t.

Molly Stevens

When bones are broken beyond self-repair, doctors take pieces of the hip bone, specifically a part called the iliac crest, and graft it where it is needed. But there’s only so much iliac crest available, and the procedure results in years of pain. But Molly Stevens has developed an alternative. Her in-vivo bioreactor system harvests stem cells from the leg bone to enable bone regeneration.

A professor in Biomedical Materials and Regenerative Medicine at London’s Imperial College, Stevens’ work in creating new biomaterials to detect disease and repair bones and human tissue has made her a rising star in life science. At this year’s Polymer Networks Group Meeting , June 19-23 at KTH Royal Institute of Technology, she will join an impressive line-up of plenary speakers.

Like biological tissue, polymer can also be made to self-heal, and that’s one of the research areas that keynote speaker Filip Du Prez, head of the Polymer Chemistry Research Group at Gent University in Belgium, and his 30 researchers are dealing with. Among others are the design of functional polymer architectures and polymer materials, various types of controlled polymerization techniques, and the development of new “click” chemistries.

Filip Du Prez

Also addressing the plenary is University of Tokyo Professor Mitsuhiro Shibayama, who is one of the world-leading researchers on the physics of so-called “soft matter” or “soft materials”.

Eva Malmström, Professor at Fibre and Polymer Technology at KTH, is proud that the conference is to be held at KTH for the first time, and says that the conference will bring together world-leading experts and graduate students from all around the

world in a dynamic mix. “It will be exciting to learn about the most recent findings in general and especially interesting to hear more about bio-based materials. Hopefully the conference’s setting will pave the way for stimulating discussions and fruitful networking”.

The plenary includes a host of international research leaders:

Dominique Hourdet, Université Pierre et Marie Curie, Paris, France — “Macromolecular assemblies in aqueous media: from controlled rheology of polymer solutions to mechanical reinforcement of covalent hydrogels”

Olli Ikkala, Aalto University, Helsinki, Finland — “Supramolecular Functionalization of Molecular Colloids and Colloidal Networks”

Mitsuhiro Shibayama

Bela Iván, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary —”Amphiphilic Conetworks as a New Material Platform of Bicontinuous Nanophasic Macromolecular Assemblies, Intelligent Gels and Unique Organic-Inorganic Nanohybrids”

James Lewicki, Lawrence Livermore National Laboratory, CA, USA — “A Multi-scale Experimental and Computational Approach to Studying Network Dynamics in Complex Polysiloxane Elastomers”

Zhigang Suo, Harvard John A. Paulson School of Engineering and Applied Sciences, Boston, USA — “Soft Materials and Soft Machines”

Françoise M. Winnik, University of Montreal, Montreal, Canada — “Biological Responses to Chitosan Substituted With Zwitterionic Groups”

Chi Wu, The Chinese University of Hong Kong, Hong Kong — “A Novel Microrheometer – Total Internal Reflection Microscope Marries Magnetic Tweezers”



Truck’s engine taps own heat for power

A 195-year-old discovery is the basis for a new system that will save vehicles hundreds of litres of fuel and reduce their carbon emissions by as much as 2 to 3 tonnes per year.

Working with automotive manufacturer Scania, researchers from KTH Royal Institute of Technology have been testing semi trucks equipped with a system that converts exhaust heat into power — with a thermoelectric generator (TEG). The voltage produced by the system can power the truck and reduce the strain on the engine, explains researcher Arash Risseh.

The TEG system operates on the principle of the thermoelectric effect, by which differences in temperature are converted into voltage — a phenomenon discovered in 1821 by German physicist Thomas Johann Seebeck, and often referred to as the “Seebeck effect”. (Watch video)

“Most fuel energy is not used to drive a truck forward,” Risseh says. “A great portion of this unused energy — some 30 percent — disappears in the form of heat through the exhaust pipes.”

How much energy are we talking about? For a truck that generates 440kW, that lost energy would total about 132kW. “That’s enough to power a typical passenger vehicle.”

Capturing this excess energy takes a load off the truck’s generator, and in turn, the engine, Risseh says. That means better fuel efficiency and lower emissions.

The Seebeck effect requires a temperature differential — cool on one end of the circuit and hot on the other, which means a truck must rely on a coolant in order to stimulate the voltage. Cooling the circuit is easier with natural alternatives, such as seawater for a ship’s engines. Ships also make good candidates for TEG because their buoyancy offsets the constraints of weight and volume that road vehicles face, he says.

TEG is also regarded as a potential energy saver in data centres that are located in cold climates. Near the Arctic circle in northern Sweden, a data centre that uses 1 Terawatt hour per year could potentially recover 1 Gigawatt per year — a savings of some EUR 100,000, he says.

The research project, which is funded by the Swedish Energy Agency, also includes partners Eberspächer, TitanX and Swerea IVF.

David Callahan

Rewinding a bike crash shows how helmets protect

What if you could go back in time and see exactly what would have happened if only you had done things differently?

That’s what researchers at KTH Royal Institute of Technology in Stockholm did with three actual bike crashes in which the riders wore no helmets. This squirm-inducing video shows the impact on an adult male’s brain when he lost control of his bike and crashed.

Then the video does something extraordinary: it reenacts the same crash and shows what would have happened if the rider had worn a helmet.

The visualization is based on computer-simulated motion recreation done by neuronics researcher Madelen Fahlstedt and colleagues at KTH Royal Institute of Technology in Stockholm (with the help of researchers at Leuven University). In order to show how much the brain’s tissues are stretched in each instance, they used a detailed computer model of the head (KTH head model) and reconstructed accidents. Then they compared their simulations against actual CT images of the damaged brains.

We know from epidemiology that helmets are more likely to protect people, but up until now, we could only guess at how much protection your brain tissues really get. Few studies have gone beyond epidemiological surveys to accurately map the cause-and-effect relationship between helmets and protection, she says.

“We can see how much the brain tissue is stretched in the collisions, and that the tissue is stretched most in those areas where the impact occurred,” Fahlsted says.

In the reenactments, an ordinary bicycle helmet reduced the brain tissue’s stretch rate between 33 to 43 percent in the three accidents studied, she says. “Given the factors in our study, we have also been able to see a reduced risk of 54 percent for concussion when using bicycle helmets.”

Not only do helmets decrease stress on brain tissue, they also reduce the risk of skull fractures, she says.

“We saw a great reduction of stress on the bones, as a result of wearing a bike helmet, from 80 megapascals down to 10 megapascals. This figure indicates how much load you put on a given surface, and translated into more understandable terms, this means a reduction from 100-percent risk of skull fracture down to 10 percent for those wearing helmets.”

David Callahan

Endangered fish need better PR to win over hearts

Unloading fish from a trawler to buckets containers truck
Unloading fish from a trawler to buckets containers truck. What would be your reaction if lambs or cows were treated this way?

Atlantic halibut
Bluefin tuna
Acadian Redfish
Orange Roughy
Goliath grouper
Winter skate
Beluga sturgeon
Bocaccio Rockfish
European eel
Maltese Ray

No, that’s not today’s seafood menu. Although I wouldn’t blame you for wondering if it were, because, truth be told, it sure looks like one. And a pretty good one at that.

What it is, in fact, is a list of the top 10 most endangered species of fish in the world.

Let that thought sink in for a second. Kind of alarming, no?

When the subject of extinction comes up, I tend to think of mammals — elephants and polar bears and Siberian tigers. Who doesn’t? But, fish? Hardly. Whales come to mind, sure, but that’s because they’re smart and they sing and play. And they’re not fish!

Do a Google image search for “endangered species”, and what you get are page after page of majestic creatures — the lion, the rhinoceros, owls and gorillas — roaming and at rest in their habitats. Furry and feathered creatures that have one thing in common: they — just like us — live on land.

animals image
These are the results when I searched “endangered species”.

And none of them appear on any menu you’ll ever see. When it comes to the land animals we consume, our markets prefer livestock, not hunting. But for seafood, it’s another tale. Fishing is really about plundering natural habitats.

We look at fish as nothing more than food.

And perhaps due to its vastness, we seem to regard the oceans with a sense that they can take all kinds of abuse — that the seas are some kind of infinite reservoir of life.

Even though we know better, our collective attitude to the ocean might spring from the fact that destruction of its ecosystems is happening where we can’t observe it and relatively few of us can experience it. As they say: out of sight, out of mind.

But why do fish get short shrift when it comes to public’s interest in protecting wildlife? Susanna Lidström is an ecocriticism researcher with the Environmental Humanities Laboratory at KTH Royal Institute of Technology who has been looking into this question.

Massive humpback whale playing in water captured from Whale whatching boat. The marine giant is on its route from New Zealand to Australia
Massive humpback whale playing in water.

“Even on land, it is a fact that some species — almost always so-called charismatic mammals — win the sympathy of the public in a completely different way than the more inconspicuous animals, although they also play very important roles in different ecosystems,” she says. “The sea reinforces the problem.”

And the creatures that we “harvest” from the sea are — let’s face it — a little alien. Their unblinking, expressionless eyes are a metaphor for impervious mindlessness. Scaly, slimy and coldblooded, they don’t even breathe the way we, or lions or even whales, do. And they make dubious cuddle toys for children, too.

Granted, I’ve seen some fluffy Nemo toys and they are really cute. But fish don’t have fur, so it’s a bit of a cheat. Imagine the reaction if you gave a 4-year-old a rubber fish to cuddle up with in bed. Why would anyone do that?

Mouth of the giant grouper in the deep blue water
A giant grouper

But by turning a cold shoulder to the lowly fish, we risk more than hurting its feelings — which we all know they don’t have because they can’t feel pain, right?

Lidström offers an example: “Time and time again we see how decision-making goes against scientific advice about overfishing, probably because pressure from the fishing industry is not countered by public demand for greater protection of fish species.”

The political decision-making thus far reflects the obvious: fish need better PR if they’re going to get the consideration that mammals and birds benefit from. Not that some people don’t try. Groups like the World Wild Fund do wonderful work on behalf of fish, but it is perhaps telling that the WWF relies on an image of a cuddly panda bear as its symbol.

And I suppose that’s unavoidable. If the logo had a fish in it, people would assume it’s a fishing club.

For fish, finding any sign of friendship on land is as hard as finding oxygen. Even people who care about wild fish talk about their populations as “fish stocks” and their habitats as “fisheries”, terms that convey the message that fish exist only for commercial exploitation.

It’s a peculiar status for these creatures. Everyone wants them hunted down and brought to their table, but if even a single species, such as the bluefin tuna, were to vanish from the seas, we’d be horrified.

Or maybe we wouldn’t. We just can’t help ourselves.

David Callahan


Six reasons why foam packaging from biomass should replace Styrofoam

Full frame closeup of a grey Polystyrene surface
Full frame closeup of a grey Polystyrene surface

KTH researchers recently developed a method of using wood cellulose to create a material similar to Styrofoam. The product is patented under the name Cellufoam. So, why is this good news?

Well, aside from it being an egregious waste of petroleum (this stuff isn’t going to last forever), polystyrene foam is just an awful material and we either have to learn how to live without it or replace it with something else. Here are six reasons why:

  1. Polystyrene contains carcinogens and neurotoxins, namely styrene and benzene — not exactly the kinds of things you want leaching into a hot cup of joe, or that warm chocolate you treat the children to. Which brings us to the next bad thing about
  1. What would you say about a pair of eyeglasses that was designed to cause gradual blindness, or a shampoo that made your hair fall out? Well, polystyrene containers leach toxic styrene when they come into contact with warm food or drink, alcohol, oils and acidic foods. How perverse is that? One of main things that Styrofoam is used for — storing things we consume — inevitably adds poison to our meal, or drink. Thanks!
  1. Styrene has been linked to cancer, impaired memory, nervous system effects, loss of vision and hearing, and I could list a bunch of other things, but do you really need to hear more?plastic and foam garbage, pollution of environment
  2. Polystyrene is not biodegradable. In fact, it can take hundreds of years for polystyrene to break down in the environment. And when it does — it’s bad news.
  1. Because of food contamination, polystyrene foam food packaging is not suitable for recycling.COLOURBOX8780374
  1. Because the foam is about 95 percent air, it blows easily out of landfills and travels easily in gutters and storm drains, it winds up in waterways, becoming one of the biggest types of marine debris worldwide.
  2. And it’s not renewable. Any food packaging made with Styrofoam can be substituted with paper products, which are renewable. Petroleum is precious, and until we replace petroleum-based plastics with bio-plastics, we might want to think very carefully about all the critical uses we really need the material for, such as as heart valves, plastic syringes and a million other things you might find in a hospital.