The city that Mother Nature built

Unfortunately, we’ve chosen to build our cities out of two completely unsustainable materials: steel and concrete. If we want to lower carbon emissions we are going to have to invent new materials pretty quickly. Could looking to nature hold the key? We find out more

Pretty much ever since we stopped using branches and twigs to build homes, we’ve thought of concrete and steel as the materials of choice when it comes to construction. But these materials are responsible for as much as a tenth of worldwide carbon emissions, so we have two choices: either we start producing steel and concrete in more energy-efficient ways, or we create new building materials to take their place.

Ask the US’ Defence Advanced Research Projects Agency (DARPA) or University of Cambridge bioengineer Michelle Oyen what they think the cities of tomorrow will be made of, and they might answer bone, bark, egg shells or spider’s silk.

DARPA and Oyen are part of a growing movement that sees biomimicry, or the principle of seeking sustainable solutions to human challenges by emulating nature’s time-tested patterns and strategies, as the future of construction.

The benefit of letting nature guide our construction techniques is obvious. For example, despite knowing its cost to the environment we use steel because it’s really good at taking tension, but spider’s silk is stronger than steel and more flexible – because it is a perfectly designed composite of proteins. It makes sense then that we stop using steel and prop buildings up with spider’s silk; apart from anything else who wouldn’t want to live in a city that looks like Spiderman has had a particularly busy night of webslinging. The reason we don’t is because the construction industry is set in its ways, and we believe we can ‘green’ steel. But why bother when nature has already given us a better alternative?

Disrupting construction

“The construction industry is a very conservative one,” said Oyen in a statement. “All of our existing building standards have been designed with concrete and steel in mind. Constructing buildings out of entirely new materials would mean completely rethinking the whole industry. But if you want to do something really transformative to bring down carbon emissions, then I think that’s what we have to do. If we’re going to make a real change, a major rethink is what has to happen.”

Featured image courtesy of eVolo

Featured image courtesy of eVolo

If we want to move to a more sustainable future then some of our preconceptions about construction are going to have to be disrupted. The principal assumption that has to change is: just because we can make buildings out of concrete and steel, doesn’t mean we have to or we should. The cement industry, for example, is one of the world’s most polluting, accounting for 5% of man-made carbon-dioxide emissions each year, as making and transporting concrete puts a massive burden on the environment.

There seems to be little desire to change. Retrofitting old kilns to improve thermal efficiency could lower concrete manufacturers’ energy usage by two-fifths, according to the Carbon Disclosure Project, but even this would only represent symbolic greening.

What is needed is drastic change, and what could be more dramatic than replacing concrete and steel with bone? While bone cities may seem haunting at first glance, bone is stronger than steel, and just one cubic inch of it can bear a load four times greater than concrete. Bone gets its strength from having a roughly equal ratio of proteins and minerals – the minerals give bone stiffness and hardness, while the proteins give it toughness or resistance to fracture. Bones also have the advantage of being self-healing, which is another feature that engineers are trying to bring to biomimetic materials.

DARPA’s living materials

The US’ research agency, DARPA, has already realised that living materials provide many advantages, as they can be grown where needed, self-repair when damaged and respond to changes in their surroundings. The agency has recently launched the Engineered Living Materials (ELM) programme to create a new class of materials that combine the structural properties of traditional buildings with the added benefits that living systems provide.

Imagine that instead of shipping finished materials, we can ship precursors and rapidly grow them on site using local resources

“The vision of the ELM programme is to grow materials on demand where they are needed,” said ELM programme manager, Justin Gallivan. “Imagine that instead of shipping finished materials, we can ship precursors and rapidly grow them on site using local resources. And, since the materials will be alive, they will be able to respond to changes in their environment and heal themselves in response to damage.”

Being able to construct with living materials could offer significant benefits; however, DARPA has commenced its ELM programme because it concluded that scientists and engineers are currently unable to easily control the size and shape of living materials in ways that would make them useful for construction. But Oyen and her team at the Oyen Lab (which came into being in 2006 at Cambridge University’s Engineering Department) have been constructing small samples of artificial bone and eggshell, which they believe could be scaled up and used as low-carbon building materials.

Oyen’s laboratory

“What we’re trying to do is to rethink the way that we make things,” said Oyen. “Engineers tend to throw energy at problems, whereas nature throws information at problems – they fundamentally do things differently.”

Oyen cites eggshells as an example of nature doing something totally different that we can mimic. “If you look at a chicken, they go from zero to eggshell in 18 hours,” said Oyen in an interview with the Guardian. “It’s almost a millimetre thick, 95% ceramic and it has this organic component that makes it very tough. The whole thing has been put down in an extremely short period of time, at an ambient pressure and at body temperature, barely above ambient temperatures.”

Nature has already given us an idea of the kinds of resilient and sustainable materials that could be used to build the cities of the future. Oyen’s eggshells are already much more resistant to fracture than manmade ceramic. The experiments being carried out by Oyen and DARPA will hopefully contribute to the construction industry taking the way nature creates sustainable structures and putting this knowledge into practical use. Then we may well see skyscrapers made out of bone and eggshell.

factor-archive-28“From a timeline perspective,” said Oyen, “for the last 10 years we’ve been trying to figure these things out. We’ve probably still a few more years to go and then maybe the following decade will be taking all the things we’ve learned and being able to apply them to making new materials.”

Adding stem cells to the brains of mice “slowed or reversed” ageing

Albert Einstein College of Medicine scientists “slowed or reversed” ageing in mice by injecting stem cells into their brains.

The study, published online in the journal Nature, saw the scientists implant stem cells into mice’s hypothalamus, which caused molecules called microRNAs (miRNAs) to be released.

The miRNA molecules were then extracted from the hypothalamic stem cells and injected into the cerebrospinal fluid of two groups of mice: middle-aged mice whose hypothalamic stem cells had been destroyed and normal middle-aged mice.

This treatment significantly slowed aging in both groups of animals as measured by tissue analysis and behavioural testing that involved assessing changes in the animals’ muscle endurance, coordination, social behaviour and cognitive ability.

“Our research shows that the number of hypothalamic neural stem cells naturally declines over the life of the animal, and this decline accelerates aging,” said senior author Dongsheng Cai, M.D., Ph.D., professor of molecular pharmacology at Einstein.

“But we also found that the effects of this loss are not irreversible. By replenishing these stem cells or the molecules they produce, it’s possible to slow and even reverse various aspects of aging throughout the body.”

To reach the conclusion that stem cells in the hypothalamus held the key to aging, the scientists first looked at the fate cells in the hypothalamus as healthy mice got older.

The number of hypothalamic stem cells began to diminish when the mice reached about 10 months, which is several months before the usual signs of aging start appearing. “By old age—about two years of age in mice—most of those cells were gone,” said Dr. Cai.

Images courtesy of the Mayo Clinic.

The researchers next wanted to learn whether this progressive loss of stem cells was actually causing aging and was not just associated with it.

To do this, the scientists observed what happened when they selectively disrupted the hypothalamic stem cells in middle-aged mice.

“This disruption greatly accelerated aging compared with control mice, and those animals with disrupted stem cells died earlier than normal,” said Dr. Cai.

Finally, to work out whther adding stem cells to the hypothalamus counteracted ageing, the scientists injected hypothalamic stem cells into the brains of middle-aged mice whose stem cells had been destroyed as well as into the brains of normal old mice.

In both groups of animals, the treatment slowed or reversed various measures of aging.

The scientists are now trying to identify the particular populations of microRNAs that are responsible for the anti-aging effects seen in mice, which is perhaps the first step toward slowing the aging process and successfully treating age-related diseases in humans.

Self-driving delivery cars coming to UK roads by 2018

A driverless vehicle designed to deliver goods to UK homes is set to take to the road next year after the successful conclusion of an equity crowdfunding campaign.

Developed by engineers at The University of Aberystwyth-based startup The Academy of Robotics, the vehicle, Kar-Go, is road-legal, and capable of driving on roads without any specific markings without human intervention.

Kar-Go has successfully raised £321,000 through Crowdcube – 107% of its goal – meaning the company now has the funds to build its first commercially ready vehicles. This amount will also, according to William Sachiti, Academy of Robotics founder and CEO, be matched by “one of the largest tech companies” in the world.

Images courtesy of Academy of Robotics

The Academy of Robotics has already built and tested a prototype version of Kar-Go, and is working with UK car manufacturer Pilgrim to produce the fully street-legal version.

The duo has already gained legal approval from the UK government’s Centre for Autonomous Vehicles, meaning the cars will be able to immediately operate on UK roads once built.

The aim of Kar-Go is to partner with suppliers of everyday consumer goods to significantly reduce the cost of deliveries, and the company’s goal in this area is ambitious: Sachiti believes Kar-Go could reduce delivery costs by as much as 98%.

Whether companies go for the offering remains to be seen, but the company says it is in early stage discussions with several of the largest fast-moving consumer goods companies in Europe, which would likely include the corporations behind some of the most recognisable brands found in UK supermarkets.

Introducing Kar-go Autonomous Delivery from Academy of Robotics on Vimeo.

While some will be sceptical, Sachiti is keen to drive the company to success, and already has an impressive track record in future-focused business development. He previously founded Clever Bins – the solar powered digital advertising bins found in many of the nation’s cities – and digital concierge service MyCityVenue – now part of SecretEscapes.

“As a CEO, it is one of my primary duties to make sure Kar-go remains a fantastic investment, this can only be achieved by our team producing spectacular results. We can’t wait to show the world what we produce,” he said.

“We have a stellar team who are excited to have begun working on what we believe will probably be the best autonomous delivery vehicle in the world. For instance, our multi-award winning lead vehicle designer is part of the World Championship winning Brabham Formula One design team, and also spent years as a Design Engineer at McLaren.”