Mathematical, Computational and Experimental Neurosciencehttp://hdl.handle.net/20.500.11824/6722021-09-24T23:46:13Z2021-09-24T23:46:13ZMicrobial production of advanced biofuelsKeasling, J.Garcia Martin, H.Lee, TMukhopadhyay, A.Singer, S.Sundstrom, E.http://hdl.handle.net/20.500.11824/13162021-08-06T01:00:34Z2021-01-01T00:00:00ZMicrobial production of advanced biofuels
Keasling, J.; Garcia Martin, H.; Lee, T; Mukhopadhyay, A.; Singer, S.; Sundstrom, E.
Concerns over climate change have necessitated a rethinking of our transportation infrastructure. One possible alternative to carbon-polluting fossil fuels are biofuels produced from a renewable carbon source using engineered microorganisms. Two biofuels, ethanol and biodiesel, have been made inroads to displacing petroleum-based fuels, but their penetration has been limited by the amounts that can be used in conventional engines and by cost. Advanced biofuels that mimic petroleum-based fuels are not limited by the amounts that can be used in existing transportation infrastructure, but have had limited penetration due to costs. In this review, we will discuss the advances in engineering microbial metabolism to produce advanced biofuels and prospects for reducing their costs.
2021-01-01T00:00:00ZComputing Higher Leray–Serre Spectral Sequences of Towers of FibrationsGuidolin, A.Romero, A.http://hdl.handle.net/20.500.11824/13102021-07-26T01:00:33Z2020-10-27T00:00:00ZComputing Higher Leray–Serre Spectral Sequences of Towers of Fibrations
Guidolin, A.; Romero, A.
The higher Leray–Serre spectral sequence associated with a tower of fibrations represents a generalization of the classical Leray–Serre spectral sequence of a fibration. In this work, we present algorithms to compute higher Leray–Serre spectral sequences leveraging the effective homology technique, which allows to perform computations involving chain complexes of infinite type associated with interesting objects in algebraic topology. In order to develop the programs, implemented as a new module for the Computer Algebra system Kenzo, we translated the original construction of the higher Leray–Serre spectral sequence in a simplicial framework and studied some of its fundamental properties.
2020-10-27T00:00:00ZTargeting Impaired Antimicrobial Immunity in the Brain for the Treatment of Alzheimer’s DiseaseFülöp, T.Tripathi, S.Rodrigues, S.Desroches, M.Bunt, T.Eiser, A.Bernier, F.Beauregard, P.Barron, A.Khalil, A.Plotka, A.Hirokawa, K.Larbi, A.Bocti, C.Laurent, B.Frost, E.Witkowski, J.http://hdl.handle.net/20.500.11824/12972021-07-08T07:01:52Z2021-05-04T00:00:00ZTargeting Impaired Antimicrobial Immunity in the Brain for the Treatment of Alzheimer’s Disease
Fülöp, T.; Tripathi, S.; Rodrigues, S.; Desroches, M.; Bunt, T.; Eiser, A.; Bernier, F.; Beauregard, P.; Barron, A.; Khalil, A.; Plotka, A.; Hirokawa, K.; Larbi, A.; Bocti, C.; Laurent, B.; Frost, E.; Witkowski, J.
Alzheimer’s disease (AD) is the most common form of dementia and aging is the most common risk factor for developing the disease. The etiology of AD is not known but AD may be considered as a clinical syndrome with multiple causal pathways contributing to it. The amyloid cascade hypothesis, claiming that excess production or reduced clearance of amyloid-beta (Aβ) and its aggregation into amyloid plaques, was accepted for a long time as the main cause of AD. However, many studies showed that Aβ is a frequent consequence of many challenges/pathologic processes occurring in the brain for decades. A key factor, sustained by experimental data, is that low-grade infection leading to production and deposition of Aβ, which has antimicrobial activity, precedes the development of clinically apparent AD. This infection is chronic, low grade, largely clinically silent for decades because of a nearly efficient antimicrobial immune response in the brain. A chronic inflammatory state is induced that results in neurodegeneration. Interventions that appear to prevent, retard or mitigate the devel- opment of AD also appear to modify the disease. In this review, we conceptualize further that the changes in the brain antimicrobial immune response during aging and especially in AD sufferers serve as a foundation that could lead to improved treatment strategies for preventing or decreasing the progression of AD in a disease-modifying treatment.
2021-05-04T00:00:00ZSpike-adding and reset-induced canard cycles in adaptive integrate and fire modelsDesroches, M.Kowalczyk, P.Rodrigues, S.http://hdl.handle.net/20.500.11824/12962021-07-08T07:01:52Z2021-05-03T00:00:00ZSpike-adding and reset-induced canard cycles in adaptive integrate and fire models
Desroches, M.; Kowalczyk, P.; Rodrigues, S.
We study a class of planar integrate and fire (IF) models called adaptive integrate and fire (AIF) models, which possesses an adaptation vari- able on top of membrane potential, and whose subthreshold dynamics is piece- wise linear (PWL). These AIF models therefore have two reset conditions, which enable bursting dynamics to emerge for suitable parameter values. Such models can be thought of as hybrid dynamical systems. We consider a par- ticular slow dynamics within AIF models and prove the existence of bursting cycles with N resets, for any integer N. Furthermore, we study the transition between N- and (N + 1)-reset cycles upon vanishingly small parameter vari- ations and prove (for N = 2) that such transitions are organised by canard cycles. Finally, using numerical continuation we compute branches of bursting cycles, including canard-explosive branches, in these AIF models, by suitably recasting the periodic problem as a two-point boundary-value problem.
2021-05-03T00:00:00Z