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San Juan County businesses face unknowns, hurdles when economy reopens after COVID-19 shutdown
A lingering sense of fear about the coronavirus pandemic's long-term impact is just one concern for Farmington-area business owners.
Mike Easterling
Many local business owners say they face sizable obstacles to resuming full operations after the shutdown ends.
The owners of two well-known local restaurants are especially concerned about what the future holds for their industry.
An Allen Theaters official says his company will struggle to find films to screen.
FARMINGTON — Although San Juan County was excluded from an order by Gov. Michelle Lujan Grisham on April 30 easing restrictions on business operations in New Mexico, many local merchants affected by the COVID-19 shutdown are hopeful that at some point this summer, they will be able to open their doors to customers and resume operations.
But even if that happens, they say, they are likely to face sizable hurdles in getting their business operations back to full speed.
The governor's changes to the public health order permitted some nonessential businesses to reopen through curbside service or on an appointment-only basis. The order applied to businesses such as gun shops and pet services. It also allowed golf courses and state parks to reopen.
But the order did not allow gyms, barber shops and hair salons, casinos, indoor malls or movie theaters to reopen, nor did it allow restaurants to welcome back dine-in customers.
The order did not apply to San Juan, McKinley or Cibola counties, where the virus continues to take a heavy toll.
MORE:San Juan County excluded in order easing coronavirus business restrictions
The shutdown has forced many businesses in the state to curtail or halt their operations. With no end to the pandemic in sight, some of those merchants are worried that even when they can reopen their doors, their situation will be far from ideal.
"It's going to be different for each business," Jamie Church, the president and CEO of the Farmington Chamber of Commerce, said about the restrictions and challenges merchants will continue to face for the foreseeable future.
Church said her organization is working with the San Juan County Business Response Team to help local business owners understand what to expect in terms of how they will be permitted to interact with customers. But she acknowledged that many elements of the resumption of economic activity include enormous unknowns.
"It's not going to be like, 'Monday's here, and we're all going to be back to business as usual,'" she said. "It's going to be a process."
The merchants interviewed for this story said they are worried about a number of issues, including whether they will be allowed to operate at full or partial customer capacity, how their supply lines will be impacted with reported shortages looming, how many of their employees will be willing to return to work and how the public will react to the continued threat of the virus.
"All of the above," said Martin Caddell, owner of The Cave Men's Grooming in Farmington, responding to a question about what has him most concerned.
The Cave has been closed since the shutdown went into effect in March and will remain shuttered until the governor alters her public health order or allows it to lapse. Caddell said he is itching to resume operations, but he knows even when he does, things won't quickly go back to normal in his shop.
Caddell is anticipating there will be a limit to the number of customers he can welcome inside at any one time, and he expects his barbers will be required to wear gloves, face masks and perhaps other protective gear when cutting a client's hair. It's also likely that the customers themselves will be required to cover up, he said.
"It's pretty hard to cut a guy's hair if he's wearing a face mask that ties around the back of his head," Caddell said with a chuckle, citing an example of how impractical some of those potential restrictions could be.
Even so, Caddell insisted he doesn't operate from a position of fear, and he looks forward to the day when he and his staff can get back to work.
"This is not fun. This is not ideal for anybody, and we'll attack the opportunity to go back to work with as much ferocity as we can," he said.
Church said as the reopening of the economy occurs in phases, she expects communities like Farmington to encourage consumers to support mom-and-pop businesses as opposed to the big-box stores that have escaped most restrictions.
"There's going to be a real push for local businesses to be able to do business in some fashion," she said. "The bigger stores have been essential, but I do think there's going to be quite a bit of push on behalf of locally owned businesses."
A 'bleak' future for restaurants?
Few sectors of the economy have been hit as hard by the shutdown as restaurants, especially those that operate under a dine-in model. While some of those eateries have adapted by moving toward take-out or delivery service, the shutdown has hampered their business and forced most of them to furlough or lay off many of their employees.
Many restaurant owners anticipate being allowed to open their doors to dine-in customers at some point over the next several months, but they understand that social distancing requirements will remain in place, mandating that only a percentage of seats ranging from 20 to 50 percent may be occupied.
They also anticipate having a certain amount of trouble accessing inventory from their suppliers, and they aren't sure if folks will want to enjoy a meal in public after weeks of being told to keep their distance from other people.
Randy Hodge, owner of Rubia's Mexican restaurant in Aztec, takes a pessimistic view of the future of his industry.
"I don't think it's ever going to happen," he said of a return to normal for restaurant operators. "I hope I'm wrong, but I foresee the future as being very bleak. I believe they've convinced people that you have to be very cautious. … I have no idea what to expect, but I'm prepared for the worst."
Hodge said he normally has 35 employees but is down to eight because of the shutdown.
In the early stages of the shutdown, his restaurant began selling fresh produce and some other items that had become scarce in grocery stores under a farmers market model in an attempt to maintain sales.
Hodge said he is considering doing some other things unique to the industry that might help his numbers because he believes he no longer will be able to rely on his former business model, even if an when all restrictions are lifted.
"If we hadn't opened that (farmers market), we wouldn't be open," he said of the way social distancing restrictions have impacted his business. "It's allowed us to continue to operate and keep a few people employed."
MORE:An Aztec restaurant is now offering groceries during the coronavirus pandemic
Hodge also is offering takeout service, but he said a big part of the experience of dining out is the energy and atmosphere a diner enjoys from being around other people. Take that away, or reduce it substantially, and the experience is diminished considerably, he said.
John Silva, the owner of the Three Rivers Brewery enterprises in downtown Farmington, echoed that sentiment.
"The restaurant business is a very social business," he said. "For us to open without being social is going to be very tough."
The limitations on seating capacity are only part of the new reality that could present major difficulties for restaurateurs. Hodge and Silver both confessed to being clueless about whether people will feel safe about venturing back out for a meal when they have the option to do so.
"We don't know until that day happens," Silva said.
Church said she won't be surprised if it takes diners a while to feel safe going out to eat again.
"I think people are going to be hesitant for a while about going out to a restaurant," she said. "It may take people a while to be ready to do that."
Hodge said his business is down 80 percent since the shutdown started, and he said he'll be shocked if his sales climb back to 50 percent of their average for the last five years even when he can welcome diners back inside.
"Having said that, I have a great following and a great clientele and a great market," he said. "But if I can stay open, I will be one of the lucky ones."
Silva said he isn't interested in reopening the dining rooms of his establishments under severe restrictions on capacity. That doesn't allow him to make enough money to make the effort worthwhile, he said.
"I can't operate a restaurant at 50 percent," he said. "This is going to be a crunch on my staff."
MORE:New Mexico restaurant group offering financial help to laid-off workers
Silva said he has been forced to lay off or furlough all but a handful of his nearly 100 employees over the past few months. He said his business has been hit by a series of circumstances — an increase in the state's minimum wage in January, the closure of a section of Main Street for Complete Streets construction and now the COVID-19 shutdown — that have conspired to eat up most of his profit.
"My business has been crushed," he said. "I got the perfect storm."
Hodge and Silva said both their enterprises are experiencing minor problems obtaining their normal inventory from their suppliers because of disruptions in the market. But they said the bigger issue could be how they are expected to manage their employees when they can resume dine-in service.
They are taking it as a given that all employees will be required to wear masks and gloves. But will that apply to diners, as well?
Silva voiced concern that he would be required to monitor the health of his employees, taking their temperature before and during a shift, to make sure they are not displaying any symptoms of the virus.
Those kinds of issues worry Hodge, too. And even though he expects to see a strong response initially if and when he can reopen his dining room, he foresees a future in which people eat out far less than they used to. He said the model he is moving toward — part restaurant, part retail outlet — could become the standard as people embrace one-stop shopping.
"I think there's going to be a mindset that the fewer stops you have to make and the fewer contacts you have to make, the better," he said.
Silva emphasized that he has no intention of closing the brewing operation that he has watched grow and thrive for more than 20 years. But he acknowledged the profound sense of discouragement he is feeling.
"I'm lost," he said. "I don't know what to say. I'm hoping personally we survive this, but something tells me right now it's a whole new ball game."
Movie theaters fixed up, but nothing to show
Other segments of the economy have been deeply impacted, as well.
Russell Allen, whose family has operated the Allen Theaters chain throughout New Mexico, Colorado and Arizona for generations, also has seen his business closed throughout the shutdown, and there is no indication of when the cinemas will be allowed to reopen.
The company president said even when his theaters are allowed reopen, they will have difficulty finding films to screen.
"That's the biggest challenge," he said, noting that film production has come to a standstill, and the studios are unwilling to release most movies that are in the can until market conditions improve substantially.
"They're not going to release anything until they can get back 75 percent of what they thought they could make," he said.
Allen said that doesn't mean there won't be any new content, noting that the situation could provide screening opportunities for small-budget, independent films that normally wouldn't make their way into mainstream theaters. He also said it's likely that films that were still early in their run when the shutdown occurred could be brought back for a second chance.
"There's some product out there we've never played," he said. "But we won't have any Hollywood blockbusters."
The most reliable sector of the moviegoing market is young people, Allen said, and that means that any new films that are released will be targeted for them. So if you like to watch slasher films, you're in luck, he said.
"To get the ice broken, there are going to be some horror flicks the first two or three weeks," he said.
The other challenges his industry is facing are far more manageable, Allen said. The new computerized ticketing operations most theaters have adopted will make social distancing easy, as it will be easy to space out moviegoers with assigned seating.
Allen said sneeze guards easily can be installed at concession stands, and an ordering app that will go online soon will limit most interaction between attendants and customers to the financial transaction.
Additionally, hospital-grade foggers will be installed in auditoriums, allowing each room to be disinfected quickly and efficiently instead of workers wiping clean each surface between shows. Allen said showtimes also could be further spaced out, lessening the chances of the virus being spread by contact as people pass each other in the lobby.
He said even though movies traditionally attract large groups of people to a confined space, he considers moviegoing a safe activity.
"It's a social activity that has no person-to-person contact," he said, explaining that people in a crowd react together to what is happening on the screen, but they don't engage with each other physically. "It's probably safer than most things when it comes to that kind of contact."
Allen said his theaters in New Mexico will not simply reopen when they receive permission from the governor to do so, explaining that a lot of other considerations — staffing, retraining of employees and availability of movies — will factor into that decision.
He also said it makes no sense to reopen his theaters if they can't operate at a minimum of 50 percent occupancy.
But he is anticipating a good response when his operations do resume.
"I think there's going to be quite a bit of pent-up demand," he said, explaining that he recently had seen a survey indicating the top two activities most people are looking forward to indulging in again are going out to dinner and going to watch a movie.
"You can only watch so much Netflix," he said. "The movies still offer 2 or 2½ hours of pure escape from the world, and I still believe there are a lot of people who are going to be looking for that."
A guessing game for everyone
One local business owner who voluntarily closed her doors could be resuming operations this week.
Tweeti Blancett, owner of the Step Back Inn in Aztec, said she shut down her lodging establishment March 17 even though she was permitted to continue operating at reduced capacity. Blancett said she may open her doors again on May 4, but she will meet with her employees this weekend and let them decide if they feel safe coming back to work.
"A lot of our business is foreign visitors who come to do the Anasazi ruins," she said. "I noticed a lot of our cancellations were coming from Europe, and I thought, 'This should be telling us something.'"
Blancett said she feels like the time has come to resume operations, but she doesn't want her workers to feel like she's putting them at risk.
"I want to make sure everybody's comfortable with that," she said. "If they're not comfortable with it, I won't do it. It's just not worth it."
Blancett said even though hotels are considered essential businesses and have been allowed to continue operating during the shutdown, she still faces a number of unknowns like other business owners.
"I think the biggest thing everybody faces is the unknown," she said. "We don't know if, when the restrictions are lifted, people are going to travel. Will they feel safe to get out and about?"
Caddell, owner of The Cave Men's Grooming, said he isn't sure how his clients will react, either.
He said the most disappointing thing about the shutdown for him was its timing. He opened his shop 20 months ago, and he said it had become well enough established that it was on the cusp of becoming highly successful.
Caddell isn't sure if he'll be able to recapture that momentum now.
"Hopefully, this doesn't set us back too far," he said. "But for our clients who were used to getting their hair cut monthly or every three weeks, will they start to think, 'I can go every six or eight weeks now'?"
At 4,000 square feet, Caddell said his shop is the largest men's grooming establishment in the area, so he has lots of room to accommodate social distancing requirements when he is allowed to reopen. But he said a big part of what The Cave offers is social interaction, and he worries that element will be lost if barber and client are hidden under layers of protective gear.
"It's not just a person who cuts hair," he said. "That interaction is important."
The atmosphere at The Cave — with its large, overstuffed leather couches, numerous big-screen TVs tuned to sporting events, snacks and even a bar from which patrons can sip a cold drink — is designed to make customers feel welcome and comfortable. Whether that inviting atmosphere continues to hold the same appeal in the future is anyone's guess, Caddell said.
When the restrictions against barber shops are lifted, Caddell said he anticipates new cleaning requirements being put in place, and that could place an additional burden on his business.
He said the average haircut is completed in 30 minutes now. But if every piece of equipment has to be disinfected, not just cleaned, in between clients, Caddell said that average might creep up to 40 minutes — and that will affect his profitability and likely force him to raise his prices or ask his employees to take a pay cut, neither of which is an attractive idea to him.
But as a relentlessly positive person, Caddell refuses to give in to despair.
He insisted he will adjust to whatever changes are required of his business, and he looks forward to the day when he can chat up his customers once again and perhaps even exchange a high five or a man hug.
"My mindset is, I'm a puncher, not a counterpuncher," he said. "We're going to hit the ground running. We're going to do the best we can to be open for our community."
Mike Easterling can be reached at 505-564-4610 or measterling@daily-times.com.


The Minteer Group focuses on improving the abiotic-biotic interface between biocatalysts and electrode surfaces for enhanced bioelectrocatalysis. These biocatalysts include microbial cells, organelles (mitochondria and thylakoid membranes), redox proteins, and oxidoreductase enzymes. We design electrode structures for enhanced flux at electrode surfaces for biosensor and biofuel cell applications. The group utilizes a variety of electroanalytical techniques (linear polarization, cyclic voltammetry, differential pulse voltammetry, differential pulse amperometry), as well as a variety of biological and spectroscopic techniques to accomplish these goals.
Shelley Minteer is a member of Utah MRSEC.
L. Lancaster, D.H. Hickey, M.S. Sigman, S.D. Minteer, and I. Wheeldon, "Bioinspired design of a hybrid bifunctional enzymatic/organic electrocatalyst for site selective alcohol oxidation," ChemComm, 2018, 54, 491-494.
K. Hendriks, S. Robinson, M. Braten, C. Sevov, B. Helms, M. Sigman, S. Minteer, and M. Sanford, "High-Performance Oligomeric Catholytes for Effective Macromolecular Separation in Nonaqueous Redox Flow Batteries," ACS Central Science, 2018, 4(2), 189-196.
S. Abdellaoui, F. Macazo, R. Cai, A. de Lacey, M. Pita, and S.D. Minteer, "Enzymatic Electrosynthesis of Alkanes via Bioelectrocatalytic Decarbonylation of Fatty Aldehydes," Angewandte Chemie, 2018, 57, 2404-2408.
R. Cai, R. Milton, S. Abdellaoui, T. Park, J. Patel, B. Alkotaini, and S.D. Minteer, "Electroenzymatic C-C bond formation from CO2," Journal of the American Chemical Society, 2018, 140, 5041-5044.
M. Yuan, S. Sahin, R. Cai, S. Abdellaoui, D.P. Hickey, S.D. Minteer, and R.D. Milton, "Creating a low-potential redox polymer for efficient electroenzymatic CO2 reduction," Angewandte Chemie, 2018, 130, 6692-6696.
S.L. Foster, S.I. Perez Bakovic, R. Duda, S. Maheshwari, R.D. Minteer, S.D. Minteer, M.J. Janik, J.N. Renner, and L.F. Greenlee, "Catalysts for Nitrogen Reduction to Ammonia," Nature Catalysis, 2018, 1, 490-500.
D.P. Hickey, K. Lim, R. Cai, A. Patterson, M. Yuan, S. Sahin, S. Abdellaoui, and S.D. Minteer, "Pyrene Hydrogel for Promoting Direct Bioelectrochemistry: ATP-Independent Electroenzymatic Reduction of N2," Chemical Science, 2018, 9, 5172-5177.
J. Kitt, D. Bryce, S.D. Minteer, and J. Harris, "Confocal Raman Microscopy for In-situ Measurement of Phospholipid-Water Partitioning into Model Phospholipid Bilayers within Individual Chromatographic Particles," Analytical Chemistry, 2018, in press.
R.D. Milton and S.D. Minteer, "Direct Enzymatic Bioelectrocatalysis: Differentiating Between Myth and Reality," Journal of the Royal Society Interface, 2017, 14, 20170253.
L. Xia, K. Nguyen, Y. Holade, H. Han, K. Dooley, P. Atanassov, S. Banta, and S.D. Minteer, "Improving the Performance of Methanol Biofuel Cells Utilizing an Enzyme Cascade Bioanode with DNA Bridged Substrate Channeling," ACS Energy Letters, 2017, 2, 1435-1438.
S. Abdellaoui, M. Snow, I. Matanovic, A. Stephens, P. Atanassov, and S.D. Minteer, "Hybrid Molecular/Enzymatic Catalytic Cascade for Complete Electro-oxidation of Glycerol Using a Promiscuous NAD-dependent Formate Dehydrogenase from Candida boidinii," ChemComm, 2017, 53, 5368 - 5371.
M. Grattieri, N.D. Shivel, I. Sifat, M. Bestetti, and S.D. Minteer, "Sustainable Hypersaline Microbial Fuel Cells: Inexpensive Recyclable Polymer Supports for Carbon Nanotube Conductive Paint Anodes," ChemSusChem, 2017, 10, 2053-2058.
K. Knoche, K. Hasan, E. Aoyama, and S.D. Minteer, "Role of Nitrogenase and Ferredoxin in the Mechanism of Bioelectrocatalytic Nitrogen Fixation by the Cyanobacteria Anabaena variabilis SA-1 Mutant Immobilized on Indium Tin Oxide (ITO) Electrodes," Electrochimica Acta, 2017, 232, 396-403.
K. Hasan, R. Milton, M. Grattieri, T. Wang, M. Stephanz, and S.D. Minteer, "Photobioelectrocatalysis of Intact Chloroplasts for Solar Energy Conversion," ACS Catalysis, 2017, 7, 2257-2265.
C. Serov, D.P. Hickey, M. Cook, S. Robinson, S. Barnett, S.D. Minteer, M.S. Sigman, and M. Sanford, "A Physical Organic Approach to Persistent, Cyclable, Low-Potential Electrolytes for Flow Battery Applications," Journal of the American Chemical Society, 2017, 139, 2924-2927.
R.D. Milton, R. Cai, S. Abdellaoui, D. Leech, A.L. De Lacey, M. Pita, and S.D. Minteer, "Bioelectrochemical Haber-Bosch Process: An Ammonia-Producing H2/N2 Fuel Cell," Angewandte Chemie, 2017, 56(10), 2680-2683.
R.D. Milton, S. Abdellaoui, D. Dean, L. Seefeldt, D. Leech, and S.D. Minteer, "Nitrogenase bioelectrocatalysis: heterogeneous ammonia and hydrogen production by MoFe protein," Energy and Environmental Science, 2016, 9, 2550-2554.
L. Pelster and S.D. Minteer, "Mitochondrial Inner Membrane Biomimic for the Investigation of Electron Transport Chain Supercomplex Bioelectrocatalysis," ACS Catalysis, 2016, 6, 4995-4999.
K. Knoche, D.P. Hickey, R.D. Milton, C. Curchoe, and S.D. Minteer, "Hybrid Glucose/O2 Biobattery and Supercapacitor Utilizing a Pseudocapacitive Dimethylferrocene Redox Polymer at the Bioanode," ACS Energy Letters, 2016, 1, 380-385.
B. Bulutoglu, K.E. Garcia, F. Wu, S.D. Minteer, and S. Banta, "Direct evidence for metabolon formation and substrate channeling in recombinant TCA cycle enzymes," ACS Chemical Biology, 2016, 11, 2847-2853.
T. Wang and S.D. Minteer, "Effect of Riboflavin Metabolites on Mitochondrial Electrochemistry," Journal of the Electrochemical Society, 2016, 163(13), H1047-1052.
C. Tapia, R.D. Milton, G. Pankratova, S.D. Minteer, H. Akerlund, D. Leech, A. De Lacey, M. Pita, and L. Gorton, "Wiring of Photosystem I and Hydrogenase on an Electrode for Photoelectrochemical H2 Production using Redox Polymers for Relatively Positive Onset Potential," ChemElectroChem, 2017, 4, 90-95.
Y. Holade, D.P. Hickey, and S.D. Minteer, "Halide-Regulated Growth of Electrocatalytic Metal Nanoparticles Directly on Carbon Paper Electrodes," Journal of Materials Chemistry A, 2016, 4, 17154-17162.
D. P. Hickey, K.L. Knoche, K. Albertson, C. Castro, R.D. Milton, and S.D. Minteer, "Improving O2 Reduction at an Enzymatic Biocathode: Mimicking the Lungs," ChemComm, 2016, 52, 13299-13302.
T. Wang, R.D. Milton, S. Adellaoui, D.P. Hickey, and S.D. Minteer, "Laccase Inhibition by As3+/As5+: Determination of Inhibition Mechanism and Preliminary Application to a Self-Powered Biosensor," Analytical Chemistry, 2016, 88, 3243-3248.
R.D. Milton, T. Wang, K. Knoche, and S.D. Minteer, "Tailoring Biointerfaces for Electrocatalysis," Langmuir, 2016, 32, 2291-2301.
I. Wheeldon, S.D. Minteer, S. Banta, S. Calabrese Barton, P. Atanassov, and M. Sigman, "Substrate channeling as an approach to cascade reactions," Nature Chemistry, 2016, 8, 299-309.


Over the years, CMC has gathered a wealth of international experience in the feedmill industry. From the Canadian prairies to South Africa, Mauritius, Singapore, Malaysia and India, our company has applied the integrated skills of its teams to design, construct, upgrade, manage projects, commission and create automated systems for these specialized structures. CMC-designed feedmills have been rated as some of the most efficient in the world.
CMC Engineering and Management Ltd. was awarded the contract for project management, detailed engineering design, procurement, contract supervision and automation software development for various upgrades and additions to this facility.
CMC provided engineering and construction services to two Moore-Clark fish feed manufacturing plants.
CMC provided design and construction services for various feedmill and petfood plants.
CMC provided design, installation, engineering, and construction services for several Shur-Gain Division facilities.
CMC provided design engineering and construction services to Ralston Purina for their Western Distribution Centre in Strathmore, Alberta.
CMC provided engineering and project management services to Strathmore Feed for their feedmill expansion.
Various Projects - Canada Packers Inc.


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O Centro Universitário de Caratinga (UNEC) é uma universidade privada situada nas cidades de Caratinga e Nanuque, estado de Minas Gerais.

Informações Gerais
O UNEC é mantido pela Fundação Educacional de Caratinga (FUNEC), que se define como uma instituição pública de direito privado. A sede está situada no centro da cidade de Caratinga.

Histórico
A FUNEC foi fundada em 1963 e reconhecida de utilidade pública pela Lei Municipal 638/70 e pela Lei Estadual5750/71. A instituição se integrou ao sistema estadual. Porém, em 1990, optou por extinguir esses vínculos. Em 1975, passaram a ser oferecidos os cursos de licenciatura de Letras, História, Matemática e Pedagogia. A pós-graduação Lato sensu iniciou-se em 1995. A partir dessa época várias outras graduações foram abertas.

Referências
Site do Centro Universitário de Caratinga, 2009.

Ligações externas
 Centro Universitário de Caratinga (UNEC)

Caratinga
Construções de Caratinga

redpajama_set_name: RedPajamaWikipedia


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University of Toronto, Faculty of Applied Science & Engineering
Chem Eng
Mass Spec Facility
COVID-19 Protein Manufacturing
BioZone CREATE
About BioZone
What is Bioengineering
Mass Spectrometry Facility
Protein Production, Screening, & Crystallization
Anaerobic Digestion Testing Services
Other BioZone Facilities
Full Faculty Members
Associate Faculty Members
Researchers (PDFs, RAs & Technicians)
BioZone Association
amir.arellano@mail.utoronto.ca
Amir Arellano
Structural and Molecular Insights of the Evolution of Parasitic Receptors of Striga hermonthica
Amir is a PhD student from the Cell and Systems Biology Department, currently working in the Savchenko Lab where he performs X-ray Crystallography and large scale protein purification for enzymatic analyses of parasitic receptors.
Strigolactone receptors in Striga hermonthica, crystallographic, biochemical, and genetic studies.
Striga spp. (Witchweed) is an obligate parasitic plant that attaches to the host roots to deplete them of nutrients. In Africa, the most destructive Striga species S. hermonthica parasitizes the major food crops sorghum, rice, millet and maize with yield losses ranging from 30 -100%. Presently, the most common method of Striga control is hand weeding, which is time-consuming, labour-intensive and disproportionately carried out by women and children.There are a number of potential solutions to the Striga problem, and breeding approaches are presently the most economically sought method of parasitic weed control. There are examples of improved genetic resistance to Striga in rice, sorghum, cowpea, and maize, however, complete resistance has not been attained (Afr J Plant Sci 8, 492, 2014). This is most likely due to the high genetic variability that is a consequence of the obligate outbreeding mating system of Striga hermonthica. This genetic variation not only results in resistance breakdown but almost certainly determines local host range and virulence. Thus, crop resistance across different parasitic plant populations will be difficult to achieve (Heredity 108, 96, 2012). This genetic complexity indicates innovative approaches will be required to eradicate Striga that exploit weaknesses in its lifecycle and an understanding of how this parasite evolves and adapts. However, such approaches also require a mechanistic molecular understanding of the Striga lifecycle.The overarching goal of this project is a complete understanding of Striga hermonthica SL receptors from the fundamental mechanism of perception to their evolution and population biology. Longer term, the information will be exploited to eradicate Striga from the Sub-Sahara Africa. Genetic variation most certainly contributes to SL perception and sensitivity and understanding how this mechanistically occurs is paramount to perturbing the system in ways in which the parasite will not be able to adapt. Biochemical and structural analysis of the Arabidopsis and the Striga receptors gives us some understanding of which amino acids may be important in determining SL receptors perception (Science, 349, 864 (2015), Science, 350, 203, (2015)). Comparisons of the low sensitive Arabidopsis SL receptor (AtHTL) and the highly sensitive Striga ShHTL7 receptor binding pockets identifies 8-10 key amino acids that most likely contribute to SL specificity and responsiveness.
MASc Student
ethan.agena@mail.utoronto.ca
Ethan Agena
Engineering microbes and microbial communities to produce valuable compounds from waste streams
Ethan's work revolves around engineering microbes and microbial communities to produce valuable compounds from waste streams. In particular, his project focuses on developing the alkane biosynthesis pathway in anaerobic chain elongating bacteria which are garnering interest for industrial waste valourization. He is a MASc student co-supervised by Profs. Lawson and Mahadevan.
M.A.Sc Student
olivia.bulka@mail.utoronto.ca
Olivia Bulka
Engineering Microbial Communities for Bioremediation
Olivia's research involves the analysis and engineering of metabolic networks within microbial communities to degrade chlorinated groundwater contaminants. She is co-supervised by Professor Elizabeth Edwards and Professor Krishna Mahadevan.
Microbial community engineering
joseluis.cadavidcardenas@mail.utoronto.ca
Jose Cadavid Cardenas
Modulating cancer-associated fibroblasts in a 3D tumour model towards a better treatment of pancreatic cancer.
Cancer-associated fibroblasts (CAFs) are a non-malignant cell population in the tumour stroma with a prominent pro-tumorigenic role in many cancers. In particular, CAFs are highly implicated in the lethality of pancreatic cancer, one of the deadliest forms of cancer. My work will focus on understanding the interaction between CAFs and tumour cells by culturing them in vitro in 3D tumour models. We will look for ways of modulating the behavior of CAFs towards an anti-tumorigenic one, thus helping us to fight the tumour from within and to enhance current treatments for pancreatic cancer.
xcharlie.chen@mail.utoronto.ca
Xu (Charlie) Chen
Correlative Microscopy in Biological Samples
Charlie's research involves electron microscopy sample preparation protocol developing and correlative microscopy study on mixed microbial culture. A novel biological electron microscopy sample preparation protocol by using Ionic liquid to maintain the "wet" sample in its nature state has been developed. In the future, the use of fluoresces in situ hybridization (FISH) can help to identify the different species and correlate to SEM morphology so that make it available to study the interaction between the different species in the mixed culture.
Correlative Microscopy; Microbial Dark Matter; Ultra-small Microorganism; Fluorescence in Situ Hybridization;
Biological samples such as biosludge and microbial culture contain a large amount of different components. It is a mixture of live and dead microorganisms, extracellular polymeric substances (EPS), fibers and inorganic matters. The efficiency of relative treatments such as sludge dewatering and contaminates degradation highly depend on the contributions of the different compositions. The size of those components various from tens of nanometers to hundreds of micrometers. The visualization study of these components need be carried by optical and electron microscope. The correlative microscopy combines two techniques enabling the use both optical and electronic analysis techniques on the same sample. For example, optical techniques, such as fluorescence staining, fluorescence in situ hybridization (FISH) could in principle be used with SEM and energy dispersive spectroscopy (EDS). However, current conventional sample preparation method cannot suit to both microscopy. Also, the involved dehydration and drying processes for the biological EM sample preparation make it enable to present the nature state of sample.
In order to solve these problem, I use a novel correlative sample preparation method ionic liquid exchanging. The ionic liquid is a conductive liquid salt at ambient temperature and also has very low vapor pressure which makes it very stable in the vacuum EM chamber. These properties enable a wet sample can be observed in its nature state and also makes it very easy to switch between different microscopy. Currently, an appropriate protocol has been developed and the further study of mixed culture species identification and interaction will be carried on.
M.A.Sc. Student
kiki.chan@mail.utoronto.ca
Yee Kei (Kiki) Chan
Nutrient Enhancement Using Moringa oleifera
Kiki works under the supervision of Professors Levente Diosady and Yu-Ling Cheng. Her research focuses on identifying potential uses of Moringa oleifera, a plant abundantly found in the tropical and subtropical regions, as a nutrient enhancement or supplement.
Food fortification and global food security
Over two billion people worldwide are affected by micronutrient deficiencies, with populations living in lower and middle income countries disproportionately affected as a result of food insecurity. Micronutrient deficiencies have devastating consequences ranging from the deterioration of an individual?s physical health to a nation?s economic growth, which in turn perpetuate the poverty cycle. Industrial food fortification of staple foods and condiments is a cost-effective and quick method for improving the nutritional status of communities most affected by micronutrient deficiencies. Processes for the industrial fortification of condiments are well-established, but possess challenges in stability and storage. Hence, endeavours in search for additional suitable food fortification vehicles are necessary in order to extend the reach of fortified foods, especially for those living in lower and middle income countries. Recent interest has arisen on the potential for using bouillon cubes as a food vehicle for industrial fortification. Bouillon cubes are widely used amongst households of all socioeconomic groups and its level of usage are consistent, which lends its suitability for industrial food fortification. Bouillon cubes contain both oil and water-soluble components, which could be suitable carriers for hydrophilic and hydrophobic micronutrients. Currently, salt and monosodium glutamate components constitute to over 50% of each bouillon cube by weight. As the control of sodium intake is of public health interest, the feasibility for the reduction of sodium content with regards to flavour retention will also be evaluated concurrent to evaluating bouillon cubes? suitability for food fortification.
samantha.cheung@mail.utoronto.ca
Samantha Cheung
Manipulation of algal biofilm communities through attachment surface and physiochemical conditions
Microalgae can be used to make a variety of materials including biofiuels. With fast growth rates and minimal growth requirements, they are a promising alternative to fossil fuels. In order to lower processing costs of algae biofuels, algae can be grown as biofilms in photobioreactors. My work aims to maximize product yield from algal biofilms by manipulating physiochemical conditions and attachment surface in order to select for species that are abundant in the product of interest. Maximizing yields and lowering production costs is a necessary step in order for algal biofuels to become commercially viable in the future.
Environmental biotechnology – algal biofilms
Microalgae have become a popular area of research for the production of biofuels and bioproducts because of their potential to compete with conventional sources of fuels and materials in a low-cost and environmentally friendly way. In order to be cost competitive with inexpensive products such as fossil fuels, inexpensive feedstocks such as wastewater and flue gas must be utilized in algal systems. Growing microalgae as a biofilm can utilize these inexpensive feedstocks while also reducing the cost of dewatering when compared to planktonic systems. However, non-sterile biofilms contain a variety of different organisms, some of which, may not produce the desired products. In order for algal biofilms to be economically competitive, there needs to be a better understanding of the communities and how to control them. The objective of my research is to determine whether species in algal biofilms can be manipulated by their attachment surface. Molecular biology techniques will be used to quantify individual biofilm species. This will contribute to the development of genetic techniques and fundamental knowledge in this emerging area of research. Additionally, this will be the first attempt at manipulating biofilm community composition through material. This research has incredible potential for the optimization of algal biofilm product yields where algal species with desired products can be selectively grown over other biofilm organisms. Algal biofilm species selection and control is a necessary step for algal biofuels to become an economically viable source of biofuels and bioproducts.
Ph.D. Student ruhi.choudhary@mail.utoronto.ca
Ruhi Choudhary
Engineering of probiotic strains for the targeted production of therapeutic molecules.
Crohn's disease is one of the most common chronic inflammatory diseases of the small and large intestine. The symptoms include diarrhea, fatigue, weight loss and abdominal pain due to inflammation of the lining of the digestive tract. Currently, there is no known cure for the disease. The symptoms can be managed using medication but not the underlying cause. The gut microbiome consists of trillions of microbes that have huge potential to impact our physiology by contributing to metabolic functions, regulation of immune system and resistance to pathogens. The interaction between microbes and gut cells is an important one as it can trigger immune response to dysbiosis. Probiotics are living medicine, which help the gut stay healthy by maintaining a good balance between the 'good' and 'bad' microbes. The gut microbiome of a Crohn's disease patient differs from that of a healthy patient in terms of microbial composition and mutations in epithelial gut cells. My goal is to genetically engineer probiotic strains to produce therapeutic molecules and assess the effect on the gut cells to help treat Crohn's disease.
Crohns disease is one of the most common chronic inflammatory diseases of the small and large intestine. The symptoms include diarrhea, fatigue, weight loss and abdominal pain due to inflammation of the lining of the digestive tract. Currently, there is no known cure for the disease. The symptoms can be managed using medication but not the underlying cause. The gut microbiome consists of trillions of microbes that have huge potential to impact our physiology by contributing to metabolic functions, regulation of immune system and resistance to pathogens. The interaction between microbes and gut cells is an important one as it can trigger immune response to dysbiosis. Probiotics are living medicine, which help the gut stay healthy by maintaining a good balance between the good and bad microbes. The gut microbiome of a Crohns disease patient differs from that of a healthy patient in terms of microbial composition and mutations in epithelial gut cells. My goal is to genetically engineer probiotic strains to produce therapeutic molecules and assess the effect on the gut cells to help treat Crohns disease.
Ph.D. Student ileana.co@mail.utoronto.ca
Ileana Co
Probing the Interaction of Macrophages in the Pancreatic Cancer Microenvironment
Immunotherapies have emerged as promising therapeutics for solid tumours like Pancreatic Ductal Adenocarcinoma (PDAC), but unfortunately still fail due to a poor understanding of how immune cells in the tumour microenvironment (TME) are modulated to favour tumour progression. My project is about understanding how highly plastic immune cells called tumour associated macrophages (TAMs) interact with the tumour microenvironment to promote immunosuppression and tumorigenesis using a unique in vitro rollable 3D tumour model called TRACER. Overall, we aim to understand how macrophage and tumour interactions are changed in small molecule gradients such as hypoxia in the TME using big data techniques like single cell RNA-seq and metabolomics to hopefully identify a new class of novel drug targets for immunotherapies and subsequently validate these targets in vivo.
patrick_diep@outlook.com
Patrick Diep
Engineering Nickel Uptake and Storage with Bacteria
The challenge of meeting future mineral demands is alarmingly complex. Earth's high-grade primary metal reserves are depleting, and stricter environmental regulations are pushing mining companies to reduce their waste. This is calling for new technologies to complement pyro-/hydrometallurgy techniques and remediate the wastewater effluents. Biotechnology holds promise as seen in the fields of biomining where microbes assist metal extraction, and bioremediation where microbes remove metal impurities from waste effluent. Underpinning these two fields is bioadsorption, a well-studied phenomenon where metal ions adhere to the surface of the cell and can be desorbed for collection. Bioabsorption and bioaccumulation, the uptake and storage of metal ions inside the microbe, has been explored far less as an enabling biotechnology for mining. My project's objective is to understand how bioadsorption, bioabsorption, and bioaccumulation can be rationally combined to develop genetically-engineered microbes able to sequester nickel from leachate and waste effluent. This is to be done through characterization of nickel binding and transport proteins, followed by genetic engineering of acid-resistant bacteria to use these proteins for metal extraction and remediation.
Biomining and Bioengineering
Supplying future mineral demands is alarmingly complex. Earth???s high-grade metal reserves are depleting, and stricter environmental regulations are pushing mining companies to drastically reduce their waste output. Biotechnology has the potential to alleviate such burdens as seen in the fields of biomining where bacteria can assist with metal purification, and bioremediation where bacteria remove impurities from the waste effluent. Underpinning these two fields is a well-studied phenomenon known as bioadsorption where the metal ions bind to the surface of the cell and can be desorbed for collection. Bioabsorption and bioaccumulation, the uptake and storage of metal ions inside the bacteria, has been explored far less as an enabling biotechnology. This is despite their own advantages like higher specificity for scarce metals, and the self-sustaining nature of constantly growing cells which eliminates the need for separate unit operations to produce and dispose of the bioadsorbent. My project???s objective is to study the molecular properties of nickel uptake and storage so as to generate new insights to explain their drawbacks. This will be done by exploring the interplay between nickel uptake and cellular energy expenditure, as well as the interplay between nickel storage proteins and the overall viability of the bacterial cell that is expressing it during active nickel uptake. Quantifying these relationships may generate a better understanding of how these molecular properties can give rise to the drawbacks of bioabsorption and bioaccumulation, which could empower scientists to better explore how they can overcome them.
Ph.D. Student christian.euler@mail.utoronto.ca
Dynamic Control of Metabolism Using Post-Translational Modifications
Christian primarily interested in examining native biological design principles for metabolic regulation at the protein level (i.e. allosteric regulation) to develop optimization tools and techniques for metabolic engineering. Ultimately, the aim of is to build fast, continuous control systems for the rational redirection of metabolic flux toward valuable products in microbial cell factories.
Metabolic Engineering, Bioinformatics, Systems Biology
Cells of all kinds must be able to robustly (re)organize metabolic fluxes in response to environmental changes over broad timescales in order to persist. As a result, complex systems from gene regulation to metabolic-level events have evolved to integrate environmental signals and coordinate appropriate metabolic responses. At the metabolic level, fluxes may be directly and dynamically controlled via the modulation of enzyme activities by effector metabolite binding. This form of regulation is referred to as "small-molecule regulation"" (SMR)
Ph.D. Student mauricio.garciabenitez@mail.utoronto.ca
Mauricio Garcia Benitez
Understanding the Contribution of Membrane Allocation as a Constrain in Metabolic Engineering
Our research is focused on developing a resource allocation model of the cell resources including the available membrane area as a constraint in the expression of membrane-associated proteins. This project is relevant to design better and more efficient organisms to produce biofuels and chemicals increasing their tolerance to solvents or redirecting metabolic fluxes of the cell.
Metabolic Engineering
Metabolic Burden
Biofuel Production
In metabolic engineering, one of the limitations to achieve higher production rates is to lose cellular fitness due to an overwhelming metabolic burden causing undesirable and unpredictable physiological responses. Many constraints have been identified that affect directly the robustness of the strain, including energy consumption, redox balance, ribosome availability and carbon source uptake rate. Many of these constraints are considered in cellular resource allocation models, which can predict the effect of metabolic burden in the physiology of engineered strains.
However, these models have not been considered the membrane area available for essential processes of the cell such as the area required for the carbon uptake machinery, the respiratory chain complexes or other membrane-associated proteins. Past studies have proposed the limited membrane space available as another constraint that leads to an overflow metabolism, which is characterized to produce undesirable by-products such as acetate and ethanol.
In this project, we will develop a membrane allocation model and we will study the contribution of the membrane space limitation in a cellular resource allocation model. In addition, we will compare the effect of overexpressing a membrane-associated protein, such as a transporter or an enzyme, with the overexpression of a cytosolic protein. Finally, in order to reduce the metabolic burden effect caused by the expression of a membrane-associated protein, we will use a synthetic construct to achieve dynamic control of the expression during the fermentation.
Ph.D. Student hamed.ghazisaidi@utoronto.ca
Hamed Ghazisaidi
The Effect of using Bioflocculants as Conditioners on Dewatering of Biosludge
The aim in my PhD project is to find bioflocculants that can replace synthetic polymers completely or partially. We also want to study the effect of dual conditioning using a combination of anionic and cationic polymers and bioflocculants. Protein, Lignin and Nano-Cellulose are some examples of biomolecules that have the potential to be used as coagulants. We are also interested in looking into finding accessible and cheaper resources for bioflocculants; therefore, lignin and nano-cellulose can be interesting potential options to examine.
dafni.giannari@utoronto.ca
Dafni Giannari
Metabolic Modeling of Microbial Communities
Dafni works on the development of algorithms that model metabolic functions of microbial communities and can be used for the study of the gut microbiome. She is a PhD student under the supervision of Prof. Krishna Mahadevan.
saiakhil.golla@mail.utoronto.ca
Saiakhil Golla
Systems metabolic engineering for bioproduction of adipic acid.
I am currently a PhD student in prof. Mahadevan's lab. My project aims at developing and implementing tools that facilitate dynamic regulation of pathways for adipic acid production.
kiana.haddadi@utoronto.ca
Kiana Haddadi
Investigating the metabolic control routes in response to external fluctuations by developing kinetic models. Developing a repository of systematicalle assembled data on enzymes, ligands and kinetic parameters
Metabolic Engineering,
Metabolism Dynamic Simulation, Data Science, Bioinformatics
Cellular metabolism is a densely connected network of metabolites, enzymatic reactions, and regulatory interactions, which fuels the cell with biomass building blocks and energy. All living systems can regulate their metabolism when facing environmental fluctuations for adjustment to the new condition. Although cells employ several regulatory mechanisms such as transcriptional regulation and enzyme inhibition/ activation by small molecules, the latter process has not been thoroughly investigated. Moreover, the rapid adaptation to environmental changes in a matter of seconds in organisms, such as Escherichia Coli, indicates that transcriptional regulation is usually insufficient to describe cellular metabolism because it is a relatively lengthy process.
In this project, we will develop novel computational tools to study the role of small molecule regulation (SMR) of enzymes on metabolic steady states and dynamic transitions in pathway fluxes. The proposed workflow will first involve the development of a repository of systematically assembled data on enzymes, ligands, and kinetic parameters. Such a database will facilitate the creation of novel scalable models that integrate small-molecule regulation for optimal prediction of flux distributions and responses to environmental perturbations. One such modeling method, the enzyme cost minimization (ECM) framework, calculates the minimum enzyme concentration required for a given measured flux based on thermodynamics, saturation, and reversibility of the enzyme(s) involved. The integration of SMR into the ECM framework will improve predictions of protein abundances on varied substrates and will expand our understanding of how cells handle transitions between carbon sources by investing in excess protein. Ultimately, our objective is to expand the foundational knowledge of SMR in order to understand how it could be manipulated to facilitate metabolic engineering and/or drug target choice.
gwyneth.jordan@utoronto.ca
Gwyneth Jordan
Anaerobic digestion of organic waste
My name is Gwyneth Jordan and I am currently a M.A.Sc student under the supervision of Dr. Elizabeth Edwards. I will be conducting my research on anaerobic digestion studying organic waste and the production of methane on a microbiological level.
s.kalhour@mail.utoronto.ca
Sadaf Kalhour
TRACKING THE MOTION OF WATER IN BIOSLUDGE
The activated sludge process is one of the most common techniques being used for wastewater treatment of organics in wastewater treatment plants because of its relatively low cost, reliability, and ease of implementation. There are challenges and costs associated with the handling and disposal of a by-product produced during activated sludge process, biosludge, which has been an issue for several industries including pulp and paper industry, due to its high amount of water (about 98%) and poor dewaterability. Furthermore, approximately 60 percent of the total wastewater plant costs are allocated to sludge management. Moreover, there is no direct visualization of water motion in the biosludge flocs. Therefore, understanding how the water flows through the flocs can be beneficial as can enhance fundamental understanding of the dewatering process. The aim of my research project is to obtain a better and more mechanistic understanding of biosludge dewatering by studying the water motion through the flocs. To accomplish this, I am looking at the biosludge flocs in a microfluidic channel by using the confocal microscope in combination with FRAP method.
MEng Student
farah.kubeer@mail.utoronto.ca
Farah Kubeer
Techno Economic Analysis on ECR-Bioproduction process
I am an MENG student under the supervision of Professor Radhakrishnan Mahadevan at Biozone centre. I am currently investigating the economic feasibility of an Electrochemical Carbon dioxide reduction (ECR) – Bioproduction process by conducting an in-depth technoeconomic analysis (TEA), using process design and simulation tools to study and analyze a variety of possible scenarios.
n.landon.brace@mail.utoronto.ca
Natalie Landon-Brace
Tissue-mimetic platforms, pancreatic cancer, cancer immunology
sofia.lemak@utoronto.ca
Sofia Lemak
Characterization and Engineering of the minimal RNA-guided Cascade complex from Escherichia coli
Sofia is working on characterizing the activity of E.coli Type I-E Cascade components with the aim to develop an alternative genome editing tool by understanding the specificities and limitations of the natural Cascade complex. This is done through purification of minimal Cascade components and in vitro characterization of their activity compared to wild-type Cascade. She works under the supervision of Alexander Yakunin.
Characterization and Engineering of the RNA-guided Cascade Complex from Escherichia coli
The Clustered Short Palindromic Repeats (CRISPR) immunity system utilizes a wide range of effector complexes in order to target and destroy invading nucleic acids. In the Type I systems, all are similar multi-subunit complexes, with varying composition. The CRISPR-associated complex for antiviral defense (Cascade) from the Type I-E system of Escherichia coli has been shown to be a versatile tool for bacteria to protect themselves against invading generic elements during CRISPR immunity. Type I is the most abundant CRISPR type in all organisms studied and several Type I Cascade complexes have shown versatility in complex composition. While the structure of the E.coli Cascade has been solved, the precise mechanism of action is not completely understood. Working both in the Interference and Adaptation stages of immunity, the role of Cascade has been shown to vary, and the specifics of the interactions between protein, RNA and DNA have not been described. By analyzing the proteins and substrate sequences in their native state we can eliminate unnecessary components and create a more efficient complex. In order to better understand the specificity and flexibility of the Cascade complex, my project goal is to characterize both the crRNA and protein components of the E.coli Cascade with respect to assembly and function. Elucidating the minimal requirements for each of these components that are still able to efficiently bind target DNA will lead to a clearer understanding of the mechanisms involved as well as the creation of a more flexible system that can be applied to several aspects of biology.
sergio.lunanino@mail.utoronto.ca
Sergio Andres Luna Nino
LOW COST, HIGH-HRT ANAEROBIC DIGESTERS FOR PULP AND PAPER MILL SECONDARY SLUDGE
My research is to study microbially-driven anaerobic treatment of pulp and paper mill secondary sludge with the goal to recommend low-cost reactor operation. In these anaerobic digesters, microbes convert secondary sludge to usable biogas and reduce the amount of remaining sludge, which is economically and environmentally advantageous. Economically feasible anaerobic digesters may be in the form of low-rate, high-residence time lagoon reactors that facilitate anaerobic activity. An economically feasible anaerobic digester strategy for secondary sludge could lower mill-wide operating costs and make mills more competitive.
nadia.morson@mail.utoronto.ca
Nadia Morson
Chlorinated Solvent Biodegradation
Nadia's research involves treatment of contaminated groundwater by anaerobic reductive dechlorination. She works under the supervision of Professor Elizabeth Edwards.
Chlorinated solvents are common groundwater and soil contaminants, as a result of poor disposal practices from industry. Bioaugmentation provides a solution, as microorganisms can anaerobically metabolize these toxic compounds. Dechlorinating microbes, such as Dehalococcoides mccartyi, are able to degrade highly chlorinated compounds, such as perchloroethene and trichloroethene, into ethene, a non-toxic end-product. KB-1, a mixed microbial culture used for bioaugmentation, contains multiple strains of D. mccartyi which allow for successful degradation of PCE. In collaboration with Cornell University, we have received a sample of a mixed dechlorinating culture called Donna II, that contains only D. mccartyi strain 195.
Putative mobile elements or genomic islands have been identified using bioinformatics in D. mccartyi genomes. One of these islands contains vcrA, a gene that encodes a reductive dehalogenase catalysing hydrogenolysis of vinyl chloride to ethene. It is unknown if and how these genomic islands are mobilized within microbial communities.
In an attempt to observe horizontal gene transfer (HGT) among different strains of D. mccartyi, the KB-1 culture was mixed with Donna II to create a culture called DKB, and grown under different conditions. The absence of ammonia is being used as an environmental stressor to stimulate HGT. D. mccartyi 195 from Donna II is capable of fixing nitrogen, however does not have a vcrA gene. At the same time, D. mccartyi from KB-1 do have vcrA but cannot fix nitrogen, creating a controlled environment which would favour a D. mccartyi with both traits.
One of the ways in which this HGT event can be determined is through development of D. mccartyi strain-specific biomarkers and bioinformatical analysis. This task is challenging in that most D. mccartyi strains have >98% 16S rRNA gene sequence similarity.
Determining D. mccartyi biomarkers will be a novel discovery, and will allow for the quantification and further study of this organism in mixed culture with possible in-field applications. Additionally, understanding the role of this vcrA mobile element in HGT may provide better insight to the community evolution of these bioaugmentation cultures, and open the possibility of naturally improving substrate range of D. mccartyi strains used for bioremediation.
navya.mopati@mail.utoronto.ca
Navya Reddy Mopati
COMPOSITIONAL ANALYSIS OF CORN FIBRES
Navya is a M.Eng student currently pursuing her research project in Master's Lab. She is working on Sugar recovery from corn fibres and their compositional analysis.
owen.mototsune@mail.utoronto.ca
Owen Mototsune
Oxidative enzymes for synthesis of bio-based crosslinkers
Owen is pursuing a MASc with Professor Emma Master, studying the use of carbohydrate-active enzymes to produce polyol crosslinkers from hemicellulose, an underused and undervalued by-product of the pulp and paper industry. In particular, Owen's research is concerned with the upscaling of enzyme production, the enzymatic conversion of carbohydrates to crosslinkers, and the characterization and evaluation of these crosslinkers.
jonalbert.obnamia@mail.utoronto.ca
Jon Obnamia
Sustainable production of biofuels
Jon is working on a kinetics-based enzymatic hydrolysis model for the optimization of hydrolysis process parameters and prediction of sugar concentration profiles. He is part of Bradley Saville's research group.
Biofuel Production Processes
Lignocellulosic Ethanol Production
Aviation Biofuel Production
The transportation sector contributes 22-27% to worldwide annual greenhouse gas (GHG) emissions from the combustion of fossil fuels. From annual global transportation GHG emissions, about 75% typically comes from road transport while 10% comes from aviation transport. Emissions from the transportation sector are projected to increase based on demand forecasts and continued fossil fuel use. To combat this upward trend, less carbon intensive biofuels are being developed for commercial deployment to replace some of the demand being met by fossil fuels. Full life cycle assessment is necessary to critically evaluate the environmental impacts of biofuels and determine the likelihood that these biofuels can achieve their environmental objectives.
folake.oyewole@mail.utoronto.ca
Ade. Oluwafolakemi Oyewole
Formulation of Functional Beverages from Three Sub-Saharan African Indigenous Herbs
Folake is part of Professor Levente Diosady's food engineering group and her research is looking into developing functional beverages from Sub-Saharan indigenous herbs: Moringa oleifera, Hibiscus sabdariffa and Cymbopogon citratus. She will also be looking into enhancing the functionality of the beverages if necessary through fortification using microencapsulation techniques.
chester.pham@mail.utoronto.ca
Chester Pham
Development of engineered biosensors for the detection of small molecules and metabolites
Chester is co-supervised by Krishna Mahadevan and Alexei Savchenko and focuses on the development of engineered biosensors. This project seeks to develop a screening method for the discovery of novel biosensors that can be used for virtually any chemical and apply this screen to engineer biosensors for specific compounds of interest. These biosensors will be key to the development and optimization of biosynthetic pathways that will enable the production of chemicals from renewable sources at a commercial scale.
Synthetic Biology, Metabolic Engineering, Protein Engineering
katherine.picott@mail.utoronto.ca
Katherine Picott
Investigating Substrate and Structural Differences Within the Reductive Dehalogenase Enzyme Family
Reductive dehalogenases are key enzymes involved in the biotic degradation of halogenated pollutants. Katherine's research is focused on developing tools for better characterization of this enzyme family, identifying how structure plays a role in defining the substrate ranges of particular dehalogenases, and looking for new reductive dehalogenation activity in anthropogenic environments. Increasing the understanding of this enzyme family will improve bioremediation efforts as well as facilitate their use in other industrial applications.
vera.pieters@mail.utoronto.ca
Vera Pieters
development of a co-culture platform to study the detrimental effects of obese fat on muscle regeneration.
With the global rise in obesity, there is interest in understanding interplay between fat and other tissues, such as skeletal muscle. In obese patients, fat cells overtake skeletal muscle resulting in inflammation, which impairs normal muscle activity. In the lab of Alison McGuigan, I will be working on creating a co-culture platform to study the detrimental effects of obese fat on muscle regeneration.
sofia.pimentel@hotmail.com
Sofia Pimentel Araujo
evaluation of the biodegradation potential (aerobic and anaerobic) of native microbes from contaminated sites
A PhD student from Federal University of Pernambuco (Brazil) who is evaluating the biodegradation potential (aerobic and anaerobic) of native microbes from a contaminated site in Camaçari-BA, Brazil, in degrading dichloroaniline (3,4-DCA and 2,3-DCA), o-dichlorobenzene (DCB), and dichloronitrobenzene (3,4 and 2,3-DCNB).
f.salama@mail.utoronto.ca
Fawzi Salama
Fawzi's research involves metabolic modeling of microbial communities. He works under the supervision of Professor Radhakrishnan Mahadevan.
Metabolic Engineering, Microbial Communities
Microbial communities, assemblies of more than one interacting microbial species, are essential to human and environmental heath. Communities in the soil provide nutrients to plants, communities in the ocean help regulate the planets carbon balance, and communities in the human body aid in the digestion of fibers and provide essential short-chain fatty acids. A simplified representation of this process is shown in the figure below. Typically, however, microbial communities are composed of hundreds or thousands of members. While individual species can be isolated and studied in vitro, communities composed of a large number of species are difficult to study using currently available experimental techniques. Mathematical modeling can aid in this task.
Using the sequenced genome and other biochemical data, the network of metabolic reactions in a species can be constructed, and flux balance analysis (FBA) can be used construct predictive models for a single species [1]. Furthermore, Dynamic FBA (dFBA), an extension of FBA, can be used to account for dynamic behaviours [2]. The goal of my research is to apply this technique and others to the modeling of microbial communities by improving, extending and generalizing previous efforts in this regard [3]. This research will aid in the study of natural microbial communities. It will also aid in the exploitation of synthetic communities for industrial applications, in which there has been growing interest in recent years.
1. Orth, J. D., Thiele, I. and Palsson, B. (2010). What is flux balance analysis? Nature Biotechnology, 28:245 248.
2. Mahadevan, R., Edwards, J. S. and Doyle, F. (2002). Dynamic flux balance analysis of diauxic growth in Escherichia coli. Biophysical Journal, 83:1331 1340.
3. Zhuang, K. et al. (2011). Genome-scale dynamic modeling of the competition between Rhodoferax and Geobacter in anoxic subsurface environments. ISME Journal, 5:305 16.
anupama.sharan@mail.utoronto.ca
Anupama Sharan
Fungal oxidoreductases for upgrading technical lignins to new bio-based polymers
Anupama is working under the co-supervision of Dr. Emma Master and Dr. Elizabeth Edwards. Her research is focused on value addition to the bioeconomy by upgrading under-utilised industrial (or technical) lignin sources to novel bio-based polymers.
Bioprocess and Environmental Engineering
Globally, majority of the biomass-based product development efforts have focused on degrading the cellulose, hemicellulose and lignin fractions to smaller, readily utilizable molecules. Given the complexity of these fractions, the cost of hydrolysis technology development often does not justify the value obtained from the end products. By contrast, our group concentrates on biocatalytic approaches to upgrade and functionalize intact biomass components. Specifically, I will biochemically characterize fungal oxidoreductases (e.g., peroxidases and laccases) predicted to act on diverse lignin sources, including technical lignins. These enzymes are known to enhance the reactivity and water miscibility of diverse lignins and consequently catalyse conversion to novel, bio-based polymers. A combination of analytical and surface modification tests including time of flight secondary ion mass spectrometry (ToF SIMS), asymmetric flow field flow fractionation, NMR, and HPLC/GC ? MS will be used to characterize the lignin pre and post enzyme action and thereby analyse the efficiency of the process. The research will also include techno-economic and feasibility assessments as well as life cycle analyses of the bio-products being developed.
leonardo.shen@mail.utoronto.ca
Heping (Leo) Shen
Leo is a PhD student under the joint supervision of Prof. Vlad Papangelakis and Prof. Elizabeth Edwards
kavya.siddartha@utoronto.ca
Kavya Siddartha
Metabolic engineering of microbes for sustainable and scalable chemical production.
Kavya primarily works on metabolic engineering of microbes for sustainable and scalable chemical production. Her focus has been designing modular biosynthetic pathways based on carbon-carbon bond formation, and modular host engineering. Her research interests include metabolic engineering, synthetic biology, and industrial biotechnology.
sheida.stephens@mail.utoronto.ca
Sheida Stephens
Engineering Photosynthetic Cell Factories
Sheida's research focuses on using light energy to produce chemicals via photosynthetic bacteria using a joint computational-experimental approach. Sheida is co-supervised by Prof. Allen and Prof. Mahadevan.
alexandre.tremblay@mail.utoronto.ca
Alexandre Tremblay
Engineering of microbial communities for the production of high-value chemicals
Inspired by nature, my project aims to increase the yield of the production of desired chemicals through the engineering of microbial communities. Doing so will require the adaptation of current modelling techniques to extend their use to target metabolic pathways that implies more than one organism.
MASc Candidate
kimberly.tok@mail.utoronto.ca
Kimberly Tok
Techno-economic Assessment and Life Cycle Analysis of Adipic Acid Production from Lignin
Research currently being conducted on using lignin as a feedstock for making value-added products. This research is motivated by the perspective that the use of lignin to produce a co-product generates more value for a lignocellulosic biorefinery than its traditional use of being burned for power generation. The potential economic and environmental value that upgrading lignin into a value-added co-product depends on what product is being derived from the lignin. In my research, adipic acid has been chosen as the co-product to be studied because it is a high value chemical that is used in the production of nylon-6,6. Adipic acid is also traditionally produced using non-renewable petroleum sources as a feedstock and the manufacturing process generates a significant amount of nitrous oxide, a potent greenhouse gas. Due to the environmental issues associated with the conventional production of adipic acid, research is being conducted on the production of adipic acid from renewable resources, such as lignin from lignocellulosic biomass. By using process models, techno-economic analyses, and life cycle assessments (LCA), my research aims to identify the economic and environmental values energy generation and the upgrading of lignin into adipic acid has for a biorefinery and to compare the value generated by these different uses of lignin to one another. The technical and economic viability and environmental performance of adipic acid production from lignin would also be compared to that of the conventional production process.
a.vatandoust@mail.utoronto.ca
Azadeh Vatandoust
Azadeh is currently working towards her PhD under the supervision of Professor Levente Diosady.
Multi-Micronutrient Fortification of Salt
Azadeh's research is focused on developing cost-effective technology for reducing micronutrient deficiencies through fortification of iodized salt with zinc alone and with other micronutrients such as iron, folic acid, and vitamin B12. The major challenge facing this project is the potential interactions between different micronutrients which may result in degradation of the micronutrients, reduction of their bioavailability and unfavorable organoleptic changes, hence using a physical barrier between these components is required.
kaushik.venkatesan@mail.utoronto.ca
Kaushik Raj Venkatesan
Enhancing the performance of synthetic biological circuits
My research aims at improving the robustness and response speed of genetic circuits in synthetic biology. Specifically, I am studying methods to enhance the performance of the genetic toggle switch, by examining natural switching circuits such as the lambda phage switch. By improving understanding the methods to improve these devices, I aim to make efficient synthetic switches that can be used in metabolic engineering and other applications.
Metabolic Engineering, Synthetic Biology
Microorganisms have been used to produce several chemicals of industrial and pharmaceutical importance over the past few decades. The advent of metabolic engineering has helped fuel an improvement in the production yields of these chemicals. However, several metabolic engineering strategies result in a growth impediment of the host organism and this results in strains that are not suitable for industrial scale production due to their low productivity.
Dynamic control of metabolism through input regulated switching of gene expression has been proposed as a potential solution to this problem. Advancements in synthetic biology have led to the creation of a device the genetic toggle switch which is able to switch the cells phenotype between stable states based on an input. Implementation of toggle switches however, has been limited due to a lack of robustness or very slow switching speed.
We hypothesize that in any synthetic biological circuit, there is an inherent tradeoff between the robustness to protein production rates and the response speed of the circuit. My work aims to examine the presence of such a tradeoff that a synthetic circuit poses on a cell through experimental evaluation using E.coli as a model host and will result in a deeper understanding of the reasons for failure of synthetic circuits. Design guidelines for synthetic biological circuits to minimize the probability of circuit failure will also be proposed.
kan.wu@mail.utoronto.ca
Kan Wu
Benzene Degradation
Kan is a PhD student working on Benzene Degradation in Prof. Elizabeth Edward's Lab.
nila.wu@mail.utoronto.ca
Nila Wu
Developing a 3D In Vitro Tumour Model to Functionally Assess Stromal Impact on Tumour Regrowth
Tumour recurrence is often unpredictable and as such remains a clinical challenge for cancer treatment. Current models for tumour regrowth in anti-cancer drug discovery relies on the 2D clonogenic assay whereby tumour cells are re-plated in monoculture after treatment to observe colony formation. However, cancer-associated fibroblasts (CAFs) are active contributors of disease progression within the stroma, that enable tumour cell proliferation and remodelling of the extracellular matrix. Moreover, targeting CAFs has received growing attention as a therapeutic strategy, due to their relative genetic stability. Another tumour regrowth model are murine studies which although better represent human systems, are low-throughput, expensive, and labour-intensive. In response to these limitations, we have developed a 3D in vitro, cell-based platform called GLAnCE (Gels for Live Analysis of Compartmentalized Environments), to investigate the tumour regrowth capacity, and concurrently the tumour regrowth mechanisms, after chemotherapy treatment. GLAnCE recapitulates tissue architecture within a scalable, high-throughput device that enables the study of single-cell and cell population biology, co-culture mechanisms, and organoid dynamics, through high-content imaging and analysis. Using GLAnCE, we have demonstrated CAF-mediated enhancement of tumour cell rate of regrowth in real-time. This functional regrowth assay will be used to perform a screen to identify compounds that inhibit CAF activity substantiating a pro-regrowth microenvironment that results in accelerated tumour recurrence. We envision that this will contribute to the discovery of a novel CAF-targeted compound, that will complement current standard-of-care.
johnny.xiao@mail.utoronto.ca
Zi (Johnny) Xiao
Heterologous functional expression using Clostridium
Many putative genes that could have important bioremediation applications fail to express well in traditional heterologous hosts such as E. coli. These genes are often from gram-positive anaerobes, which lack a representative host. Johnny's work focuses on the development of Clostridium acetobutylicum as a host to express an elusive benzene carboxylase isolated from a benzene degrading, nitrate-reducing culture. He is under the supervision of Elizabeth Edwards.
yuanzi.xu@mail.utoronto.ca
Yuanzi (Ester) Xu
Yuanzi (Ester) Xu is an MEng student in Prof. Grant Allen's lab.
mitchell.zak@mail.utoronto.ca
Mitchell Zak
APPLYING ALGAL BIOFILMS FOR THE RECOVERY OF RARE EARTH METALS
Mitchell works on analyzing potential applications for algal biofilms utilizing the waveguide photobioreactor. Currently he is looking at using algal biofilms for the separation and concentration of Rare Earth metals from mining effluents.
Bioprocess Engineering, Waste Reprocessing, and Bio-metallurgy
tianai.zhu@mail.utoronto.ca
Tian Ai (Alice) Zhu
Alice is a M.A.Sc Student in Prof. Bradley Saville's lab.
Biomining
Extraction of base metals from sulfide minerals has led to worldwide challenges with sulfide-laden tailings that represent a potential environmental problem which is costly to clean up. In addition, these sulfide-laden tailings may also contain large quantities of metals, such as nickel, gold, or copper, albeit at low concentrations, which can potentially be extracted for revenue.
Currently, the project is aiming to develop novel bioprocesses and bioleaching technologies that could treat mine discharges, thus recovering valuable metals and alleviating potential environmental risks. Since the project is currently being established in a laboratory scale for further development, assessment to potential economic and environmental outcomes associated with novel biotechnologies in comparison to conventional methods prior to implementation of the novel technologies would be beneficial. It is thus essential to translate laboratory-scale outcomes into an overall process through the use of Aspen Plus, and subsequently perform a techno-economic assessment on both existing and currently developing technologies for the management of mine discharges. In order to perform the assessment, aspects including but not limited to capital and operating costs, projection of overall performance in terms of metal recovery, improvements to water quality, and other regulatory requirements need to be considered. The outcome of the assessment could potentially help companies to identify the most viable tailing management method suitable for their mining processes.
info@biozone.utoronto.ca
BioZone, 200 College Street,
Toronto, Ontario, M5S 3E5, Canada
© 2022 Faculty of Applied Science & Engineering.

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Home » Supplemental Resources » STEM Concept Videos » Videos » Derivatives and Integrals » Electric Potential
Derivatives and Integrals
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This video begins with a review of electric field and electric potential, focusing on their similarities and differences and the way they are most commonly represented. A video clip from the Boston Museum of Science's Theatre of Electricity helps to transition into a discussion of electrical breakdown, which is described in detail. Students are asked to consider the role of the field and/or the potential in creating a spark during electrical breakdown.
After watching this video students will:
Have a clearer picture of the electric field and electric potential.
Be able to describe electrical breakdown in terms of the electric field or electric potential.
Funding provided by the Singapore University of Technology and Design (SUTD)
Developed by the Teaching and Learning Laboratory (TLL) at MIT for SUTD
MIT © 2012
Flux and Gauss' Law
Instructor Guide
Electric Potential Instructor Guide (PDF - 1.1MB)
Download this transcript - PDF (English - US)
Air is normally an insulator, but under certain conditions, it can suddenly and temporarily change into a conductor, and we end up with a spark. In this video, we'll use the related concepts of electric fields and electric potential to explain how insulators can suddenly, dramatically and temporarily become conductors.
This video is part of the Derivatives and Integrals video series.
Hello. My name is John McGreevy. I am a professor in the physics department at MIT, and today I'll be talking with you about the electric field and electrical potential.
To get the most out of this video you should already have some exposure to the electric field and electric potential. You should be able to take a mathematical expression for the field and obtain the potential, and vice versa. You should also know how to draw equipotential surfaces and electric field vectors.
Throughout this video our goal is to help you gain a clearer picture of the electric field and the electric potential. By the end of the video you should also be able to describe the process of electrical breakdown by using either the field or the potential.
Let's start with a review of electric field and electric potential. First we'll describe them conceptually. Then we'll show the mathematical relationship between them, and show some of their typical visual representations.
First, let's see what you remember. Take out a piece of paper and write down everything you remember about the electric field and the electric potential. Try to concentrate on their similarities and differences. Pause the video to do this.
Now you can compare the list you made to our list.
The electric field is generated by electric charges, and extends an infinite distance from them.
If you bring a second electric charge into a region of electric field, there will be a force exerted on it. Like all forces, that force has magnitude and direction. The stronger the charge is, the more force will be applied to it.
The electric field is a vector quantity. It has a vector value at every point in space, measured in Newtons per Coulomb or Volts per Meter.
Much like the electric field, electric potentials are created by charges and extend an infinite distance from them.
If you bring a second charge into a region of electrical potential, that second charge will gain or lose potential energy. The stronger that charge, the more its potential energy will change.
Unlike the electric field, the electric potential is a scalar quantity, which means that everywhere you look you can find a number that represents the potential, measured in Joules per Coulomb.
Let's look at two ways to envision an electric potential for a positively charged line near the origin. We're going to look at this in two dimensions to make things easier to see.
We can also draw the level curves for the electric potential function. These are called "equipotential lines," because the value of the potential is equal at every point on a given line. For instance, we might draw lines every ten volts.
If we plot the potential on the vertical axis, we end up with this mountain-like shape. We can imagine positive charges rolling down the mountain as they are pushed away from our line charge.
We can also sketch the electric field around a line charge. If we pick regularly spaced points at which to draw our electric field vectors, we end up with a picture like this one. Each vector shows the direction and strength of the electric field at that point. The longer the arrow, the stronger the field is. Here you might imagine the arrows pushing a positive charge away from our line
Displaying both the equipotential lines and the field vectors at once, we get this picture. You can see that the equipotential lines are always perpendicular to the field.
Since charges create both fields and potentials, both will be present all the time, though we might only draw one or the other.
The field and the potential are related mathematically through the gradient operator. As a vector operator, the gradient turns the scalar potential into a vector field. To go in the other direction, a line integral of the electric field turns that vector field into the scalar electric potential.
The negative sign that appears in both equations is important—the electric field points in the opposite direction from any changes in the potential. If the electric potential increases in a particular direction, the electric field points in the opposite direction.
We're going to use something called "electrical breakdown" to illustrate our concepts today. We'll start with an example, give a definition, then go into an explanation of the phenomenon. Here is a clip from the Boston Museum of Science to demonstrate the phenomenon.
Quite a dramatic demonstration! Let's look at this in a little more depth.
Electrical breakdown is defined as the process by which an insulating material in a strong electric field becomes electrically conductive. The material actually changes from being an insulator to being a conductor. In the clip you saw, this happened in the air near the Van de Graaff generator, and a large electric spark resulted.
You may sometimes hear this referred to as breakdown potential, or breakdown voltage, which is the same thing.
The exact value of the electric field needed depends on many factors, including distance, humidity, temperature, and the material itself.
Here is a simplified explanation of how electrical breakdown works in air. Consider this house in a thunderstorm.
If we zoom in on the air above the house, we can see the molecules of gas in the air.
Thunderstorms involve strong electric fields and high electric potential differences. We can represent those on our diagram.
Imagine that one electron is pulled from its atom by the strong electric field. Because the electron is negatively charged, it will accelerate against the electric field, and will eventually collide with another atom. That collision might knock another electron loose. Now there will be two electrons accelerating.
A single electron can thus create a chain reaction, where many atoms lose their electrons.
This creates a region of ionized air. Air is normally a good insulator, but the presence of ions allows it to conduct electricity.
...resulting in a lightning bolt!
Let's use the electric field and electric potential to investigate this situation further. Here are the Van de Graaff generators from the video, charged up, with a metal ball as a target.
Let's take a simplified version of the situation shown. Draw the equipotential surfaces around these two objects, and then draw in the electric field arrows as well. You can ignore the presence of the support pillars.
Here are two hints. First, the small metal ball is grounded, or "earthed," with an electrical potential of zero. Second, the electrical charge on the generator will spread itself equally over the surface of the conducting spheres.
Pause the video here to draw the equipotential lines and the field vectors.
Here's another picture of the generator with the target ball nearby.
This picture is too complex. Let's create a simpler version of the picture. That's
Now we can draw in the lines. Our equipotential lines will "hug" the surface of the conductors when they are nearby. Because the charge is spread evenly across the surface of the conductor, the whole surface will be at the same electric potential. The equipotential lines will tend to be smoother when farther away from the conductors.
Because the electric potential of the Van de Graaff generator gets up to about one million volts (or 1000 kilovolts), and we have drawn eight lines in the picture, each line must represent a difference of about 125 kilovolts.
In this view we have colored in the regions where the equipotential lines are more closely packed, or less closely packed.
In the blue area, with the close-packed lines, the gradient of the potential is larger. Because the electric field is proportional to the gradient of the potential, the places where our lines are more closely packed will have a stronger electric field.
In the red areas, where equipotential lines are far apart, the gradient of the potential is smaller. Therefore, the electric field will be weaker.
We can use this as a guide when drawing our field vectors.
Let's draw in those electric field vectors now. We have assumed here that the generator becomes positively charged, but if it were negatively charged, we could simply reverse the direction of our arrows.
Look carefully: our field arrows are perpendicular to the equipotential surfaces at all points. Check your own diagram - is this true on yours as well?
Our field arrows are longer where the equipotential lines are more closely packed—is this true on your diagram?
If you need to revise your diagram or draw a new one, do so now. If you have questions for your teacher, here is a chance to ask them.
Pause the video here.
Some of you may be confused by the terminology that is used for this phenomenon. Many people refer to the "breakdown potential" required to create a spark. However, but you may have noticed that the sparks in the video were produced where the electric field was the strongest, not where the electric potential was the highest. Turn to a friend and discuss why this is the case. Pause the video here to discuss.
If we return to the equations that relate the field and the potential, we can improve our understanding. You can see that we have a gradient term—a derivative with respect to distance.
If our potential changes slowly over distance, the field is weak, and no spark is generated. On the other hand, if the potential changes quickly over distance, the field is strong. A stronger field is more likely to remove an electron from an atom.
In fact, when numerical values are given for the breakdown potential, they are most often given in "volts per meter," which is a measurement of the electric field. The term "breakdown potential" is a little misleading, but it is still the standard terminology.
To review, the gradient connects the electric field to the electric potential. A steeper change in the potential results in a stronger electric field. We also saw that electrical breakdowns happen in areas of strong electric field, or of steep change in electrical potential.
We hope you enjoyed this clip from the Theatre of Electricity at the Boston Museum of Science. Good luck in your future studies of electricity.
It is highly recommended that the video is paused when prompted so that students are able to attempt the activities on their own and then check their solutions against the video.
During the video, students will:
Recall different aspects of the electric field and electric potential.
Discuss electrical breakdown in terms of both the electric field and the electric potential.
Draw electric field vectors and equipotential lines in a way that uses and reinforces the relationship between them.
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Schools also receive funding for children who have been looked after continuously for more than six months, and children of service personnel. For more information about Pupil Premium please click here to visit the Department for Education website.
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Technician wins support from iconic fashion brand to help children in hospital
A talented technician from Northumbria University has received support from a luxury North-East headquartered fashionwear retailer in her mission to adapt clothing for children receiving vital treatment.
Denise Crawford, a sewing machinist by trade who works at Northumbria University's School of Design, was inspired to start modifying t-shirts for children in Newcastle's Royal Victoria Infirmary (RVI) when her grandson, Finnley, was undergoing chemotherapy treatment for a brain tumour at the hospital in 2020.
Denise explained: "When children are having chemotherapy, as part of the treatment they often have a portacath or Hickman lines implanted in their chest to be accessed when having blood taken or to receive intravenous chemotherapy treatment. This usually requires the child to remove their top or take an arm out of a sleeve, which isn't always the best way for staff to have clear access. The anxiety or worry in removing clothing can make an already difficult time worse for children, particularly older girls.
"Whilst on the ward one day, my daughter-in-law and grandson were speaking to the play specialist, Lisa, who helps the children to feel as comfortable as possible while receiving their treatment. She showed them some t-shirts she'd received from a charity in America with zips in to make access easier and more comfortable for the children, but finding the right size for each child was taking a long time.
"I decided to put some zips in Finnley's t-shirts so he had different ones to wear that were the correct size for him. I realised that this could be useful for other patients so I continued to buy different styles and sizes of t-shirts, put zips in them and donate them to the ward for other children."
Since coming up with her novel idea, Denise has sent dozens of t-shirts to Ward 14 in the paediatric oncology day unit at the RVI's Great North Children's Hospital. Now her innovation has caught the attention of one of the country's most prominent fashionwear retailers, Barbour, a fifth-generation family-owned business that has been trading from its South Shields base since 1894.
Synonymous with the iconic wax cotton jacket and now trading in more than 55 countries, Barbour has donated more than 100 t-shirts which have been customised by Denise and her colleagues for children in the RVI.
Lisa Ternent, Nursery Nurse on Ward 14, said: "Our patients are anxious about having their ports accessed and removing a t-shirt can be difficult as this is often their security blanket.
"The zip t-shirts make the procedure a lot easier and more positive. When Denise started adapting the t-shirts, it was a massive help to the ward and patients. She is fabulous and we can't thank her enough."
Denise said she plans to continue supplying the RVI with customised t-shirts. Previously she purchased t-shirts from local high street stores and modified them with zips in the morning before starting work. She joined Northumbria University 16 years ago following a 20-year career as a sewing machinist in the garment industry.
"I really enjoy working with students to solve problems and create some of the wonderful designs they come up with," said Denise. "There are never two days the same and I love that I never know what the next challenge will be."
Kristen Pickering, Assistant Professor at Northumbria School of Design, said: "This is a commendable effort from Denise and her colleagues, one that has identified and tackled a real-world issue currently affecting hospital staff and young patients. This fantastic initiative also highlights how design can be successfully applied across different disciplines and social contexts."
Northumbria School of Design offer programmes in industrial, fashion, communication and innovation design, with students often exploring how design is used in the beauty industry as well as in society and culture. Art and Design at Northumbria was ranked fourth in the UK for research power in the 2021 Research Excellence Framework (REF 2021).
Any other suppliers who would like to donate t-shirts can contact Denise at d.crawford@northumbria.ac.uk
Northumbria School of Design
Northumbria's alumni include Apple's Sir Jonathan Ive, principal designer of the iPad, iPhone and iMac. Our School of Design covers the discipline areas of Industrial Design, Fashion Design and Innovation Design.


Jon and Maddee are some of our dearest friends. It was such an honor to be invited into these moments. From spending time at Jon's parents house watching him build the freaking coolest treehouse ever, to our friends pretending to propose to one another in an effort to "help" Jon prepare, to wearing gilly suits and strapping ourselves to trees while Jon asked Maddee to be his wife. We couldn't be more excited for these two to get hitched!