About
• An initiative-taking and meticulous firmware and software engineer with more than 8…
Services
Experience
Education
-
University of Iowa
-
Thesis title: "Integration of Magnetic Tweezers and Traction Force Microscopy to Investigate Extracellular Matrix Microrheology and Keratinocyte Mechanobiology"
-
-
• Notable coursework: Big Data Analytics, Bioinformatics Techniques, Biomaterials, Bioseparations, Biostatistics, Biotransport, Cell Material Interactions, Computational Genomics, Human Physiology, Implant Design, Micro/Nanofabrication, Numerical Method, Stem Cells in Regenerative Engineering, Systems Biology.
-
• Minor: Biology
• Notable courses: Biochemical Engineering, Biochemistry, Cell Biology, Chemical Reaction Engineering, Genetics, Immunology, Transport Phenomena, Process Control, Process & Plant Design, Process Numerical Methods & Analysis
Licenses & Certifications
-
-
-
-
-
-
-
-
-
-
Diplôme d'Etudes en Langue Française (DELF): A1 and A2
Centre International d'Etudes Pedagogiques (CIEP)
Publications
-
Integration of Magnetic Tweezers and Traction Force Microscopy to Investigate Extracellular Matrix Microrheology and Keratinocyte Mechanobiology
The University of Iowa ProQuest Dissertations Publishing
Ph.D. Dissertation
-
Integration of magnetic tweezers and traction force microscopy for the exploration of matrix rheology and keratinocyte mechanobiology: Model force- and displacement-controlled experiments
AIP Advances
In this work, we present a new experimental methodology that integrates magnetic tweezers (MT) with substrate deformation tracking microscopy (DTM) and traction force microscopy (TFM). Two types of MT-DTM/TFM experiments are described: force-control mode and displacement-control mode experiments. In model bead-on-gel experiments for each mode, an MT device is used to apply a controlled force or displacement waveform to a fibronectin-coated superparamagnetic bead attached to a fibrillar type I…
In this work, we present a new experimental methodology that integrates magnetic tweezers (MT) with substrate deformation tracking microscopy (DTM) and traction force microscopy (TFM). Two types of MT-DTM/TFM experiments are described: force-control mode and displacement-control mode experiments. In model bead-on-gel experiments for each mode, an MT device is used to apply a controlled force or displacement waveform to a fibronectin-coated superparamagnetic bead attached to a fibrillar type I collagen gel containing a layer of covalently attached red-fluorescent microspheres. Serial fast time-lapse differential interference contrast and epifluorescence image acquisition steps are used to capture displacements of the bead and microspheres, respectively, in response to the applied force or displacement. Due to the large number of acquired images and the dynamic nature of the experiment, new quantitative approaches are implemented to adapt TFM for the analysis of the data, including (i) a temporospatial correction algorithm for improved tracking of microsphere displacements, (ii) a method for the objective determination of L2 regularization parameters for computing incremental traction stress solutions, and (iii) an empirical means for identifying time intervals within the data that can be approximated by elastostatic conditions. We also illustrate how force and energy balances in a force-control mode bead-on-gel experiment can be used to estimate the elastic modulus of a collagen substrate. Finally, in a proof-of-concept, bead-on-cell demonstration, measurements of incremental cell–matrix traction stresses are used to observe how a force applied to a focal contact on the apical surface of a keratinocyte is transmitted to the collagen substrate below the cell.
-
Magnetic tweezers with magnetic flux density feedback control
Review of Scientific Instruments
In this work, we present a single-pole magnetic tweezers (MT) device designed for integration with substrate deformation tracking microscopy and/or traction force microscopy experiments intended to explore extracellular matrix rheology and human epidermal keratinocyte mechanobiology. Assembled from commercially available off-the-shelf electronics hardware and software, the MT device is amenable to replication in the basic biology laboratory. In contrast to conventional solenoid…
In this work, we present a single-pole magnetic tweezers (MT) device designed for integration with substrate deformation tracking microscopy and/or traction force microscopy experiments intended to explore extracellular matrix rheology and human epidermal keratinocyte mechanobiology. Assembled from commercially available off-the-shelf electronics hardware and software, the MT device is amenable to replication in the basic biology laboratory. In contrast to conventional solenoid current-controlled MT devices, operation of this instrument is based on real-time feedback control of the magnetic flux density emanating from the blunt end of the needle core using a cascade control scheme and a digital proportional–integral–derivative (PID) controller. Algorithms that compensate for a spatially non-uniform remnant magnetization of the needle core that develops during actuation are implemented into the feedback control scheme. Through optimization of PID gain scheduling, the MT device exhibits magnetization and demagnetization response times of less than 100 ms without overshoot over a wide range of magnetic flux density setpoints. Compared to current-based control, magnetic flux density-based control allows for more accurate and precise magnetic actuation forces by compensating for temperature increases within the needle core due to heat generated by the applied solenoid currents. Near field calibrations validate the ability of the MT device to actuate 4.5 μm-diameter superparamagnetic beads with forces up to 25 nN with maximum relative uncertainties of ±30% for beads positioned between 2.5 and 40 µm from the needle tip.
Languages
-
English
Native or bilingual proficiency
-
Spanish
Native or bilingual proficiency
-
Arabic
Native or bilingual proficiency
-
French
Professional working proficiency
Organizations
-
Graduate Student Senate at the University of Iowa
Senator for the Department of Biomedical Engineering
- -
Chemical Engineering Honors Society, Omega Chi Epsilon (OXE)
President
- -
Chemical Engineering Honors Society, Omega Chi Epsilon (OXE)
Treasurer
-
Other similar profiles
Explore collaborative articles
We’re unlocking community knowledge in a new way. Experts add insights directly into each article, started with the help of AI.
Explore MoreOthers named Waddah Moghram, Ph.D.
1 other named Waddah Moghram, Ph.D. is on LinkedIn
See others named Waddah Moghram, Ph.D.