BEGIN:VCALENDAR
VERSION:2.0
PRODID:icalendar-ruby
CALSCALE:GREGORIAN
X-WR-CALNAME:MIE Seminar Presentation: Interplay of Fluid Dynamics and Coll
 ective Behavior of Microorganisms
X-WR-TIMEZONE:Eastern Time (US & Canada)
BEGIN:VEVENT
DTSTAMP:20260713T085353Z
UID:tag:localist.com\,2008:EventInstance_672183
DTSTART:20140407T140000Z
DTEND:20140407T160000Z
DESCRIPTION:~~ The Department of Mechanical and Industrial Engineering Pres
 ents\n\nDr. Alireza Karimi \n\nPostdoctoral Research Associate\, Departmen
 t of Aerospace and Mechanical Engineering\, University of Notre Dame\n\nTo
 pic: Interplay of Fluid Dynamics and Collective Behavior of Microorganisms
  \n\nDate: Monday\, April 7\, 2014 \n\nTime: 10:00am to 12:00pm (Refreshme
 nts from 9:30am to 10:00am) \n\nLocation: 348 Curry Student Center \n\n \n
 \nAbstract: The collective motion of self-propelled microorganisms in a fl
 uid environment is a ubiquitous phenomenon of nature and is at the core of
  a novel area of research known as active fluids. Scrutinizing the hydrody
 namic interaction of swimming microorganisms and the surrounding fluid pro
 vides us significant insights about the underlying mechanisms of a wide ra
 nge of physical phenomena\, including biofilm formation\, bioconvection\, 
 and evolution of algal blooms. In this study\, we employed intensive numer
 ical simulations of a deterministic model of the bioconvection to capture 
 the characteristics of the patterns triggered by the coordinated swimming 
 of algae in homogenous and stratified aquatic environments. The correspond
 ing outcomes exhibit the same trend of pattern evolution as observed in ex
 perimental investigations in the literature. As a result of this study\, t
 he buoyancy ratio is introduced as the key parameter to determine if the b
 ioconvcetive plumes are suppressed by stratification arising from thermal 
 or solutal gradients in the ambient fluid. In addition\, we elucidated the
  impact of viscoelasticity on the coordinated swimming of bacteria. The fo
 rmation of biofilms is often associated with production of extracellular p
 olymeric substances which impart viscoelastic behavior to the surrounding 
 fluid. To investigate this process\, we used a kinetic model developed to 
 study the behavior of self-propelled rod-shaped particles in conjunction w
 ith Oldroyd-B constitutive equation and the Stokes equations. Using large-
 scale numerical simulations of the system\, this study demonstrates that v
 iscoelasticity promotes the localization of the fluctuations in the patter
 n of the system by inhibiting the formation of large-scale dense regions o
 f bacteria. Further\, suspensions of polymers with higher relaxation time 
 are shown to slow down the collective motion of the microorganisms.\n\n \n
 \nBrief bio: Dr. Alireza Karimi received his Bachelors and Masters degrees
  in Mechanical Engineering from Sharif University of Technology\, Iran and
  his PhD degree in Engineering Science and Mechanics from Virginia Tech in
  2012. In his dissertation\, he developed a large-scale computational fram
 ework to study the pattern formation and complex dynamics in spatially ext
 ended chaotic systems. Presently\, Dr. Karimi is a Postdoctoral Research A
 ssociate in the Department of Aerospace and Mechanical Engineering at the 
 University of Notre Dame. His current research focuses on characterizing t
 he complex interplay of fluid dynamics and collective behavior of swimming
  microorganisms using intensive numerical simulations. He has been honored
  with significant awards based upon his key scientific contributions inclu
 ding the prestigious Liviu Librescu Memorial Scholarship Award.
GEO:42.34201;-71.086197
LOCATION:Curry Student Center\, 348
SUMMARY:MIE Seminar Presentation: Interplay of Fluid Dynamics and Collectiv
 e Behavior of Microorganisms
URL;VALUE=URI:https://calendar.northeastern.edu/event/mie_seminar_presentat
 ion_interplay_of_fluid_dynamics_and_collective_behavior_of_microorganisms
CATEGORIES:Seminar
END:VEVENT
END:VCALENDAR