Holiday Closure

The Department of Mechanical Engineering will be closed from 3:00 pm on Friday, December 20th, 2019 and will re-open at 8:30 am on Monday, January 6th, 2020.

We would like to wish everyone a Safe and Happy Holiday!

See you in 2020!

Biology meets engineering in York’s stem cell research program

LEUKEMIA, MULTIPLE SCLEROSIS, Parkinson’s disease, spinal cord injuries – these are very different ailments with one thing in common: all can potentially be treated with therapies rooted in stem cells. Known since the 1960s, when they were discovered by Canadian researchers Ernest McCulloch and James Till, stem cells have incredible potential value for regenerative medicine.

Research such as that being carried out at the Stem Cell Engineering Lab at York University finds that stem cells can develop into many different types of cells within the body, with a multitude of possible functions. No other cell in the human body is so malleable. But a major obstacle is that stem cells, once removed from a donor’s body, typically only stay alive for a couple of days.

“If we try to keep them alive in a dish, they die,” explains Eleftherios (Terry) Sachlos, York’s Stem Cell Engineering Lab director and principal investigator. With a PhD in tissue engineering and 3D printing from the University of Oxford, Sachlos continued his work with stem cells during his postdoctoral research at Harvard, MIT and McMaster. He joined York in 2014.

One of his main goals in this capacity is to figure out what conditions are needed to make stem cells survive for longer periods. Demand for stem cells always outstrips supply, so being able to grow them in the lab could have tremendous payoff. “We’re asking,” Sachlos says, “how can we keep these blood stem cells alive in a dish, so that we can grow more of them?”

Terry Sachlos: Investigating stem cell therapies to improve quality of life

For Sachlos, a cell’s environment is the key: conditions in a plastic dish are nothing like those within the human body, so the first step is to be able to move beyond the petri dish to a more realistic environment. Ideally, that environment would closely resemble and mimic that of real bone marrow.

“By engineering the bone marrow, we’re creating a ‘house’ for these stem cells. We’re creating these micro-environments, so that when the cells get removed from the body, it’s not too much of a shock for them.”

The challenge of keeping stem cells alive combines basic biology with techniques drawn from engineering – which makes it perfectly suited to Sachlos’s combination of talents. “We’re using engineering principles to try to control and manipulate the cells,” he says. That includes building a 3D matrix, a sponge-like structure in which cells can live and thrive as they would in human bone marrow.

The move to a 3D environment is crucial, says Farrah Sawh, a graduate student working in York’s Stem Cell Engineering Lab. “Traditionally, cell cultures have been created in a flat, 2D plastic dish,” she says. “But we’re not 2D organisms; we’re 3D.”

The next step is to duplicate the body’s building materials – calcium, collagen, elastin and the various proteins that hold it all together. In the lab located in York’s Life Sciences Building, Sawh tries out different combinations of those key ingredients, honing in on those that produce the best results.

“If you get even half of the cells still living after five days,” she says, “then you’re doing something right.”

It’s clear that there’s a growing demand for stem cells across North America. According to a recent report, the stem cell market is increasing by some 9.5 per cent annually. “Stem cells have the potential to transform the treatment of several chronic and incurable diseases,” says Sandra Donaldson, vice-president of the Ontario Institute for Regenerative Medicine.

We’re mindful that the work that we’re doing is applied research. We want to see the benefits trickle down to patients.…

“Innovative stem cell therapies have the potential to improve the quality of life of affected patients and families,” and can also generate considerable economic benefits as the technologies become commercialized, she says. At the Stem Cell Engineering Lab, which opened last year, research is front and centre – but with an eye on commercialization. Sachlos has been working with several industry partners and has been involved with the Bergeron Entrepreneurs in Science & Technology program at York, which supports tech-based start-ups.

“We’re mindful that the work that we’re doing is applied research,” says Sachlos. “We want to see the benefits trickle down to patients, and the best way you can do that is through a commercialization route.”

Bone marrow transplants have been used to treat leukemia since the late 1950s; so far, more than one million transplants have been carried out, with some 50,000 people receiving a bone marrow graft every year worldwide.

But bone marrow transplants also offer hope for the treatment of autoimmune diseases such as multiple sclerosis (MS), Sachlos says.

Unfortunately, bone marrow transplants remain dangerous; the mortality rate is about 10 per cent. In the case of leukemia, because the disease is so deadly, patients often decide to have the transplant despite the risks.

Because MS is less deadly, patients sometimes choose to forgo the transplant and live with the disease and its consequences. But if those transplants could be made safer, it would be a big step forward, Sachlos says, and having more stem cells available could do just that.

“What if we could get that 10 per cent down to 0.1 per cent? What if we could make it safer?” That can potentially be achieved just by having more stem cells available. “The more stem cells you inject, the safer it becomes.”  ■

Link to article on York University Magazine [Fall 2019 issue]

2020 Educational Summer Camp, York University, Toronto, Canada



Solomon Boakye-Yiadom
Assistant Professor, Mechanical Engineering Department
437 Bergeron Center for Engineering Excellence
Lassonde School of Engineering, York University
Toronto, Canada

1000 Islands Fluid Dynamics

Prof. Hanson attended the 1000 Islands Fluid Dynamics Meeting held near Gananoque, Ontario, with members of his research group including Vahid Nasr Esfahani, Hossein Khanjari, Tejas Alva, and Costa Kandias. The meeting hosted over 60 technical seminars on current research that was attended by academics from Ontario, Quebec, and the North East of the United States who work in the area of fluid mechanics and heat transfer.  A summary of the presentations by Hanson’s team is given below.

Vahid Nsar Esfanani: Comparative analysis of end conditions on vortex shedding from a circular cylinder in sub-critical flow

Tejas Alva: Plasma actuator body force using a phase resolved integral approach

Hossein Khanjari: Laminar boundary layer response to an impulse forcing by a spanwise array of plasma actuators

Costa Kandias: Analysis of an expanding corner flow with turning vanes

Mechanical Engineering Undergraduate Students headed to Michigan State University to compete in their first Human Powered Vehicle Challenge (HPVC)

On April 5th, thirteen students from Lassonde School of engineering headed over to Michigan State University to compete in their first Human Powered Vehicle Challenge(HPVC) organised by American Society of Mechanical Engineers(ASME).

These students worked hard over the last 8 months designing and building a vehicle. Capstone Team A was responsible for building the shell of the vehicle while Capstone Team M built the frame and drive train. The logistics and finances were handled by the executive members of the team, Affan Behzad(President) and Julia Delongis(Treasurer).

The team had to go through different challenges over the course of three days which included:

1) Full safety inspection that comprised of static judging, manoeuvrability, stopping distance, stability at different speeds and roll bar check that required inverting the vehicle with the largest rider buckled in.

2) Drag racing against other teams.

3) Endurance race which included a rumble strip, slalom, uphill, parcel pickup/drop-off and sharp turns. These obstacles repeatedly put the design to test over the course of two and a half hours.

After successfully completing all these challenges, the team received an overall rank of 34th among the 50 universities that were competing this year.

Check out the competition pictures on their Instagram: @lassondehpvc

You are also invited to their capstone showcase on Friday April 26th, 9:00am to 2:15pm at Life Sciences Building.

Here is a full list of team:

Faculty Advisor

  • Assistant Professor Ronald Hanson, Department of Mechanical Engineering

Executives from the Lassonde Human Powered Vehicle Club

  • Affan Behzad, President
  • Julia, Treasurer

Capstone Team A

  • Affan Behzad
  • Fabio Provenzano
  • Han Sun
  • Zaid Siddiqui
  • Michael Varacalli
  • Ho Lo

Capstone Team M

  • Thane Higgins
  • Joshua Marques
  • Ridham Patel
  • Jony Sureshkumar
  • Jolayemi Sowemimo
  • Swapnil Naik

Supporting Faculty Members

  • Assistant Professor Jeffrey Harris, Department of Mechanical Engineering
  • Assistant Professor Paul O’Brien, Department of Mechanical Engineering

Lassonde Professor’s paper named influential by the Physics of Fluids Journal

Lassonde Professor Alidad Amirfazli’s paper Shedding of multiple sessile droplets by an airflow was recently marked as an influential work by the Physics of Fluids journal.  The paper featured work by Professor Amirfazli and Lassonde graduate students Aysan Razzaghi and Hossein Banitabaei.

This work illustrates how shedding of droplets can improve water management for fuel cells, as well as anti-icing for aircrafts and wind turbines.

“We have indirectly been able to probe the effect of the flow field around sessile droplets as relates to droplet removal, for the first time” said co-author Alidad Amirfazli. “We found the size of the droplets and the surface wettability didn’t have a significant effect on the shedding, which was unexpected.”

A summary of the article can be found here.