Medical Physics Certificate

Medical Physics
University of Florida
2016

Postdoctoral Residency

Medical Physics Residency
Yale University School of Medicine
2015

Doctor of Philosophy (Ph.D.)

Theoretical Physics - Topological States of Matter
Sharif University of Technology/Indiana University
1997

Master of Science (M.Sc.)

Theoretical Physics - Cosmology, String Theory and Quantum Field Theory
Sharif University of Tech.
1992

Bachelor of Science (B.S.)

Engineering
Iran University of Science and Technology
1989

Computational physicist, developing stochastic and predictive multi-scale models (Monte Carlo - Molecular Dynamics, ...) for radiotherapy of cancer / Nano Dosimetry

I am interested in multi-scale modeling of radiation-matter interaction spanning over atto- to milli-seconds, and hours to years post-radiation, with spatial scales from fermi (dimension of nuclei, proton/neutron) to nano-meter (dimension of DNA) and micro-meter (dimension of a cell, normal or cancerous) and finally to human tissues. I dig into fundamental principles in nature from high to low energies including processes involving QCD, QED, that allow calculating Klein-Nishina, Moller, Bhabha, ... scattering processes, ... the weak nuclear interactions responsible for electron capture, positron emission, ... down to condensed matter, complex systems, fractal geometry of tumor cells, and classical description of charged particle energy deposition (e.g., Bethe-Bloch stopping power) to understand the underlying collective phenomenon interplaying optimization and control of clinical outcomes in nuclear medicine, therapeutic, and medical imaging techniques. A variety of phenomena that span over E&M or nuclear couplings to the hydrodynamics of shock-waves and non-equilibrium plasma physics. Along this path, we may discover some non-trivial phenomena such as the formation of the super-critical state of nano-cavities and nano-scale shock-waves by passage of heavy charged particles subsequent by the spontaneous emission of Cherenkov photons due to the sudden collapse of cavities (see my recent publications), as at this stage, the experimentalists in the medical physics community are capable of detecting these effects. To this end, my research tends to be translational medicine and requires multi-disciplinary synergy with chemists, biologists, clinicians, mathematicians, and computer scientists (e.g., to develop machine learning and artificial intelligence, AI, techniques). Currently, I am working on several topics on developing radiobiological and radiochemical models for FLASH-radiotherapy, in particular lower cognitive reduction post radiation, using neural network theories such as Hopfield and Hodgkin–Huxley models, ... and you are more than welcome to join my group at Howard University in these exciting projects.     

Clinical Medical Physicist

Several years of experience working as a clinical medical physicist in radiation oncology departments in CT and NJ.

Radiation Physics and Dosimetry - MP 501

Heath Physics MP 503

Radiobiology - MP 601

Junior associate member of the Abdus Salam International Center for Theoretical Physics, Strada Costiera 11, Trieste, Italy, 1998.

Universite Paul Sabatier Visiting Scientist, 1999

Award from the French Government to visit the Department of Physics of Universite Paul Sabatier in Toulouse as a visiting scientist

Travel Award; Indiana University, 1995-1996

One year PhD research study as exchange student

Innovative Strategies to Enhance Radiosensitivity

Innovative Strategies to Enhance Radiosensitivity: Hyperthermia, Nanoparticles, and DNA Repair Inhibition

This chapter explores innovative strategies to enhance radiosensitivity, focusing on hyperthermia, nanoparticle-based radiosensitizers, and DNA repair inhibition. ntegrating hyperthermia, nanoparticle-based radiosensitizers, and DNA repair inhibition represents a promising frontier in enhancing RT efficacy. These approaches offer multifaceted strategies to overcome tumor radioresistance, potentially revolutionizing cancer therapy and improving patient survival rates.

A Monte Carlo simulation framework for investigating the effect of inter-track coupling on H2O2 productions at ultra-high dose rates

A Monte Carlo simulation framework for investigating the effect of inter-track coupling on H₂O₂ productions at ultra-high dose rates

To present a multi-scale formalism to reconcile the theoretical modeling and the experimental observations of H₂O₂ production and provide a mechanism for the suppression of H₂O₂  at FLASH-UHDR.

A Semiclassical Model of the Immediate Temperature Distribution

A semiclassical model of the immediate temperature distribution surrounding the track of heavy ions with therapeutic energies

Spikes of high temperature and pressure are created in the vicinity of heavy ions, especially at the Bragg peak. The expected subsequent thermoacoustic effects are however not well understood. In particular, the distribution of the densely packed primary interactions has not been considered in molecular dynamics (MDs) simulations or shock wave solutions. In this work, we derive a dedicated model to describe the primary interactions and their radial distribution, applicable to the modeling of acoustic and thermodynamic effects at the nanoscale

A Molecular Dynamics Simulation Framework

A Molecular Dynamics Simulation Framework for Investigating Ionizing Radiation-induced Nano-bubble Interactions at Ultra-high Dose Rates

We present a microscopic formalism that accounts for the formation of nano-scale bubbles owing to a burst of water molecules after the passage of high energy charged particles that lead to the formation of “hot” non-ionizing excitations or thermal spikes (TS).

Renormalization of radiobiological response functions

Renormalization of radiobiological response functions by energy loss fluctuations and complexities in chromosome aberration induction: deactivation theory for proton therapy from cells to tumor control

We employ a multi-scale mechanistic approach built upon our recent phenomenological/computational methodologies to investigate radiation induced cell toxicities and deactivation mechanisms as a function of linear energy transfer in hadron therapy. Our theoretical model consists of a system of Markov chains in microscopic and macroscopic spatio-temporal landscapes, i.e., stochastic birth-death processes of cells in millimeter-scale colonies that incorporates a coarse-grained driving force to account for microscopic radiation induced damage.

Intertrack interaction at ultra-high dose rates and its role in the FLASH effect

Intertrack interaction at ultra-high dose rates and its role in the FLASH effect

We construct an analytical model of the distribution, diffusive evolution, and chemical interaction of particle tracks in an irradiated target. We fit parameters of the model to Monte Carlo (MC) simulations of electron tracks, and include the effects of scavenging capacities of different target media. We compare the model’s predictions to MC simulations of many interacting electron tracks, and use the comparison to predict the prevalence of intertrack interactions in the parameter space where the FLASH effect is observed in vivo, and where differential reactive species (RS) yields have been observed in aqua.