Innovative Projects Realized

Processing of conducting polymers for biologica applications

Organic electroactive materials are used to produce flexible and easily processable electronic devices, such as organic light-emitting diodes, transistors and photovoltaic cells. Alongside these well-established applications, organic electroactive materials have been introduced in bioelectronics, where electronic signals are translated into ionic biosignals and vice versa. Examples of bioelectronic devices are sensors based on organic electrochemical transistors (OECTs).
The objective of this project is to provide a deeper understanding of the working mechanism of OECTs by exploring how the device electrical characteristics depend on the processing of the conducting polymer film.
Conducting polymer films will be deposited by different techniques, to explore how film processing affects the doping/dedoping processes. We will use spin-coating and vapor phase polymerization. We expect to obtain films with different doping/dedoping characteristics, which will shed light on the role of film processing on the ability of the conducting film to accommodate ions. The conducting polymer of choice for films to be processed by spin-coating is PEDOT:PSS. PEDOT:PSS is used because of its high conductivity, biocompatibility, and chemical stability. VPP will yield films of PEDOT doped with p-toluenesulfonate (or tosylate, TOS). PEDOT:PSS and PEDOT:TOS are expected to lead to different operation mechanisms of operation in OECTs. In PEDOT:PSS the dopant anions (PSS-) are essentially immobile, since they are part of a polymer chain. Therefore the OECT current modulation is controlled mainly by incorporation of electrolyte cations. In PEDOT:TOS the dopant ions (TOS-) can be released during dedoping, therefore the dedoping process is a result of both cation incorporation and anion release.
Spin-coated PEDOT:PSS films will be obtained from commercial aqueous suspensions, which need to be mixed with an organic compound (secondary dopant) to increase film conductivity. After spin-coating, the films will be annealed to temperatures higher than 100 °C to remove the excess of water and solvents. Although the role of secondary dopants is still under debate, it has been ascertained that their presence is required to achieve high conductivity. Typically employed secondary dopants are ethylene glycol, dimethyl sulfoxide, sorbitol, glycerol and, recently, polyethylene glycol. To date, it is still unclear which one of these secondary dopants is best suited for OECTs. We will investigate various formulations, with the aim to elucidate the correlation between the conductivity and the effectiveness of the doping/dedoping process.
VPP of PEDOT will be performed as follows. A layer of oxidant solution (Fe(III) p-toluenesulfonate tosylate, TOS) and pyridine dissolved in isopropanol will be deposited on the substrate. After annealing to 80 °C, the substrate will be transferred to the VPP vacuum chamber and exposed to vapors of the EDOT momoner, which will polymerize when in contact with the oxidant. Finally the substrate will be rinsed in ethanol (to remove excess of oxidant) and dried for a few hours at 50°C. This process yields PEDOT doped with the counter ion TOS-.

Global Special Interest Group (SIG) on Early Identification and Intervention in Autism

The project title is the Global Special Interest Group (SIG) on Early Identification and Intervention in Autism. Formed in 2012, the aim of this project is to enhance research impact in diverse communities through the iterative and dynamic process of knowledge translation: the synthesis, dissemination, exchange, and application of knowledge to improve quality of life for people affected by autism. The SIG is a knowledge translation network which brings together over 100 researchers, clinicians, and advocates from over 20 countries. The SIG was formed under the umbrella of the International Society for Autism Research, the largest professional organization in this area. The activities support global linkage and exchange by initiating dialogue, identifying knowledge gaps, barriers, and action priorities in autism early identification and intervention. All activities use a common toolbox that we developed and tested. The toolbox includes a review of evidence in a focus area, participant surveys to capture the experience and perspectives of researchers and practitioners in different parts of the world, obtaining expert input to address the themes identified, and finally, hosting a dialogue session (a meeting or online workshop) to build consensus and support the development of recommendations for practice and policy. Results of the surveys are analyzed and submitted for publication in a research journal and a report is prepared and sent to participants.

Climate change adaptation policy and practice: country case-study

The project will focus on a case-study of adaptation across scales in a single country (likely the applicant’s country of origin). The project is guided by the following research questions: What does adaptation look like in regions with limited formal and institutional reporting of adaptation action? In these regions, is adaptation absent, or is it occurring outside of governmental institutions (i.e. private industry or civil society)? At what scales and in what sectors is adaptation occurring, and what are the characteristics of adaptation stimuli and action? The project will systematically investigate, document, and critically assess the state of adaptation to climate change in the case-study country. This will include methodologies to systematically review and code (quantitative and/or qualitatively) a range of document sources, including on-line peer-reviewed and grey literature, and key policy documents, and well as possible phone or skype interviews with key informants. The project is targeted at the preparation of a paper in the style of a publishable manuscript.

Molecular mechanisms of synapse remodelling

In the CNS the majority of excitatory synapses are formed onto specialized structures known as dendritic spines which can undergo shape changes in the time frame of minutes to days. This inherent structural plasticity of dendritic spines even lasts into adulthood. It is still unclear why certain spines are more likely to be maintained, to provide a physical substrate for long-term information storage, while others are more structurally plastic. We have recently discovered a novel process by which mature dendritic spines can be maintained. The objective of the proposed study is to continue to contribute to the understanding of the rules that regulate the morphology and function of dendritic spines and develop novel targets for learning disorders.

Dynamics and Control of Quadrotor Vehicles

Research and development of small UAVs have accelerated over the past few years, spurred on by the progress in miniaturization of actuator, sensor and computer control technologies. A number of such UAVs are currently available commercially and many more have been developed by researchers for laboratory studies. The focus of the present project is on small UAVs (< ~5 kg in weight) and furthermore on rotary-wing rather than fixed-wing systems. Sharf's research group has been working with several rotary platforms (quadrotors) over the past five years. Problems in control, motion planning, state estimation and localization and mapping have been addressed. Sharf is interested in exploring further the following problems related to quadrotor UAVs: 1) dynamics and control for recovery from collision/impact 2) tau-control strategies for landing 3) design of UAVs with reversible thrust propellers 4) surveying and categorizing existing quadrotor platforms and developing guidelines for optimal size selection with respect to different types of missions 5) design of landing gear and control strategies for landing on ice-berg 6) inductive recharging of UAVs Student will work on a particular problem from the above list, depending on progress of research by 2015 and student's specific interests.

The duty to vote

From a purely utilitarian perspective, voting does not appear to be a ‘rational’ choice in a large electorate election if there is some opportunity cost in going to the polls, given the extremely low probability that one’s decision will be pivotal (Owen and Grofman 1984; Mueller 2003). Yet most people vote, which is known as the paradox of voting (Fiorina 1989; Grofman 1993). Why, then, do many people vote? One reason is that many persons feel that it is a citizen’s duty to vote in a democracy, they consider that this is the ‘right’, ‘ethical’ thing to do (Campbell et al.,1960, Riker and Ordeshook 1968, Verba et al. 1995, Blais 2000, Clarke et al. 2004, Blais and Achen 2012). Sense of civic duty even appears to be the most powerful predictor of voting (Blais 2000).
This moral basis for the act of voting is known in the literature as civic duty, the duty to vote or simply as “the D term”. In spite of its predictive power and popularity among political behaviour scholars, the
phenomenon remains fuzzy and unexplored. The danger exists that this attitudinal term becomes a hotchpotch for all the psychological determinants of voting outside the rational parameters. If we know
relatively little about the exact nature of civic duty, its causes are even more mysterious.
We intend to produce the first systematic study of the duty to vote. This is the logical follow-up to the book written by the principal co-investigator more than 10 years ago: To Vote or not to Vote?. This
capital work for the Political Behaviour studies (769 citations in Google Scholar) reached two main conclusions: first, the contribution of rational choice to our understanding of turnout is limited; second,
sense of civic duty is the most powerful motivation for voting. The next step is to examine in depth the sources of that belief, which is precisely what this project is about. We have identified eight research questions related to the duty to vote. We plan to write papers that
address these questions, present them at international conferences, publish some of them in top quality scientific journals, and finally produce a book manuscript. The eight research questions (RQ) are: (RQ1) How should duty be measured? (RQ2) How does it relate to other political attitudes? (RQ3) How widespread is it? (RQ4) Who feels that it is a duty to vote? (RQ5) Where does duty come from? (RQ6)
Does it vary over time? (RQ7) Does duty vary across countries and regions and, thus, according to contextual factors?(RQ8) How is duty enforced?
Since our goal is to understand why people do (or do not) construe voting as a duty, our main source of
data will consist of existing surveys. We will also make use of novel lab experiments to comprehend how the public norm that voting is a duty is enforced and new survey experiments to sort out to what
extent people feel a duty to vote as members of their society or as members of a democratic polity. We intend to collect and merge all the relevant surveys including questions about the duty to vote. A
preliminary search for surveys containing questions related to the moral obligation of voting yields no less than a hundred studies.
In short, we hope to make a substantial contribution to our understanding of the sources, both contextual and individual, of citizens’ view about whether voting is a duty or not

Combustion at microscales

Objectives: The proposed research program aims at studying the generation and propagation of unsteady compressible flow phenomena, with chemical heat release, at millimeter and sub-millimeter scales. Based on these findings, a number of biomedical and aerospace applications will be pursued in the area of high-power density microsystems.
Scientific approach: Our approach is based on the experimental observation of compressible flow phenomena at small scale using specially-built devices and on developing simple analytical models to explain the experimental observations. We then use this new knowledge to develop novel devices exploiting these phenomena.

There is great interest in continuous micro-combustion for various MEMS devices (engines, fuel cells, etc.) but only few studies have investigated the propagation of unsteady combustion waves at small scales, and never at the micrometer scale of our unique experimental facilities. So this should produce valuable new knowledge that can potentially be exploited in the design of novel high-power density microsystems.

Role of Nlrs in neurodegenerative diseases (New)

Nlrx1, belongs to NLR family of intracellular sensors that regulate mayor cellular pathway including cell death and inflammation. Previous research implicated Nlrx1 in regulation of autophagy and reactive oxygen species production during viral infection. In addition most recent publication implicated Nlrx1 in regulation of the cell death in fibroblasts cultures. Our preliminary data show that Nlrx1-/- mice are more prone to develop experimental autoimmune encephalomyelitis. The increased susceptibility of the Nlrx1-/- mice is associated with increased (2 fold) inflammatory infiltrate and induced astrogliosis (2 fold) compared to WT control. We also noted a drastic reduction (7 fold) in neuronal content in the spinal cords of Nlrx1-/- compared to WT mice. Such profound differences in the neuronal content cannot be explained by magnitude of the inflammatory response. Therefore, the cell death phenomenon that we observed has to be neuron specific.
Aim 1 is to characterize inflammation-induced cell death in primary cultures from WT and Nlrx1-/-mice.
Hypothesis: Nlrx1 inhibits inflammation-induced neuronal death. We will study inflammation-induced cell death in the mixed brain cultures that contain neurons, astrocytes, and microglia. In addition we will use oxygen/glucose deprivation model of stroke to screen several drag candidates. We will assess cell death by immunohistochemistry, flow cytometry, and Western blotting.
The results of these studies will lay foundation for development of new therapeutical agents to treat neurodegenerative diseases

Ontario Power Grid Modelling for Incorporation of Renewable Energy Sources

The research project is to model the Ontario power grid and its constituent zones in order to determine the best locations for wind turbine farms and distributed power sources. A basic model of the Niagara Zone has been constructed, involving the location of the power generation stations, major demand centres, and transmission systems. The model is to be advanced to simulate the hourly time history of power generation and demand throughout the zone. Once the past operation is accurately simulated, the model may be used to simulate the effects of incorporating distributed and intermittent renewable power sources within the grid. The past data is provided by the Independent Electrical System Operator for Ontario.

The model is to be developed in Matlab and requires the ability to interface with the necessary data files for both the operational history and wind distribution files. The wind distribution files provide the necessary data to simulate wind speeds at various altitudes and locations throughout Ontario.

The minimum final deliverable of the project is expected to be an operational Matlab simulation of the Niagara zone. The inclusion of other zones is desirable but optional.

Electrospun nanofibers for adsorption of pollutants from wastewaters

The overall objective of our research project is to develop a technology that will help many industries and more specifically the pulp and paper industry to reduce their fresh water consumption and by the same way their effluent discharge. To achieve this, it is mandatory to remove several contaminants from process waters because the reduction of fresh water consumption can only be made by closing down water systems. Therefore, reusing and recycling more process water within the mill is necessary. Unfortunately, as more process water is recycled back to the paper machine, an excessive accumulation of contaminants (dissolved and colloidal substances) in process waters results with detrimental consequences to the papermaking process itself as well as to the paper quality, and of course this is very costly. To overcome this problem, we have developed an experimental approach based on the adsorption process. We believe that if we can remove some of those contaminants from paper machine white water during the papermaking process; it will be possible to reuse it and replace an equivalent amount of fresh water, which is normally required to operate the paper machine without any disturbing problems.

The overall objective of the proposed research projet is thus to develop a filtration/adsorption device to adsorb specific pollutants (organic or inorganic) from wastewaters. The device will be made of electrospun nanofibers using various synthetic polymers as well as biopolymers.

The specific objectives of the project are:

-To manufacture electrospun nanofibers using various mixtures of polymers (synthetic/biopolymers) and to determine specific nanofiber properties (dimensions, strength, porosity, surface area, surface chemistry, etc).

– To study adsorption potential of those electrospun nanofibers towards specific contaminants (organic, inorganic).

-To determine adsorption isotherm (models) and kinetic adsorption isotherms under various experimental conditions.

The role of PML in anti-retroviral innate immunity (New)

The PML (promyelocytic leukemia) protein, also called TRIM19, is an interferon-induced antiviral factor. It directs the formation of nuclear bodies that are rich in heavily SUMOylated proteins and are often associated with viral replication sites. PML can “silence” (prevent the expression of) several viruses, including retroviruses, and its action is often counteracted by viral proteins.
We have recently set up a murine model to study the role of PML in the restriction (inhibition) of retroviral replication. By examining specific steps of the replication of HIV-1 and other retroviruses in cells isolated from wild-type or from PML-knockout mice, we can identify and characterize the effect of PML on pre- and post-integration steps.
An manuscript is in preparation, and I expect that this project will expand. By 2015, we will be conducint mechanistic studies, including:
– Microscopic analyses of PML-viral DNA co-localization
– Biochemical analyses of the physical interactions between PML, or cellular proteins found at PML bodies, with retroviral proteins and genomic DNA.
– Development of in vivo models to test the importance of PML in restricting a retrovirus.

Biomedical applications of HIV-1 restriction factors

Project: genome editing of restriction factors to confer resistance to HIV-1.

The human versions of restriction factors APOBEC3G and TRIM5alpha are unable to efficiently target HIV-1, because of 1) an inability of human TRIM5alpha to physically bind its target, the capsid protein of HIV-1; and 2) the degradation of human TRIM5alpha by the specialized HIV-1 viral protein Vif. My laboratory has isolated and characterized mutations of TRIM5alpha that confer restriction activity against HIV-1. Other groups have published that a single mutation in human APOBEC3G can make it resistant to HIV-1 Vif and thus can result in significant restriction as well. These two restriction factors act at different stages of viral replication, and it is likely that co-expressing the mutated, HIV-1-restrictive versions of TRIM5alpha and APOBEC3G would very effectively cripple the virus.
The project will thus consist in editing the human genome in cell line models in order to generate cells bearing mutations at either or both of the genes. For this, we will use genome editing approaches based on TALENs and also on the CRISPR-Cas system. Resistance of the cell lines created to HIV-1 will then be characterized by infection assays (potency, specificity, etc.). We will also investigate possible HIV-1 resistance to these tailored restriction factors, as well as the mechanism of restriction itself. We are also working at improving the efficiency of genome editing protocols, especially the homologous recombination step, through various strategies. We collaborate with partners for developing these projects toward in vivo applications, and the selected student might also work at this side of the project.
Interested students should contact Dr Berthoux for more information ([email protected]).