BioDynaMo is a biological processes simulator developed by an international community of researchers and software engineers working closely with neuroscientists. The authors have taken part in the development of the physical engine, and they are currently working on gene expression, i.e. the process by which the heritable information in a gene the sequence of DNA base pairs is made into a funct...

This essay is a recapitulation of an earlier Kramers-Krönig analysis of biological tissue, published in 2010 [1]. The intent is to both complement and bolster the antecedent analysis by furnishing supplemental clarification on the electromagnetic model employed and provide further technical details. Biological tissue is modeled a dielectric embedded in a conductor, which necessitates using both...

We investigated the propagation of light in biological tissues that have aligned cylindrical microstructures (e.g., muscle, skin, bone, tooth). Because of pronounced anisotropic light scattering by cylindrical structures (e.g., myofibrils and collagen fibers) the spatially resolved reflectance exhibits a directional dependence that is different close to and far from the incident source. We appl...

Microwave-induced thermoacoustic tomography was explored to image biological tissue. Short microwave pulses irradiated tissue to generate acoustic waves by thermoelastic expansion. The microwave-induced thermoacoustic waves were detected with a focused ultrasonic transducer. Each time-domain signal from the ultrasonic transducer represented a one-dimensional image along the acoustic axis of the...

Collagen has an important role in many biological tissues such as bone, tendon, teeth, skin and cartilage. Despite significant research efforts over the past five decades, the nanostructure of collagen is still not well known. Coherent X-ray diffraction imaging is a good candidate for addressing this issue, but it is limited as a result of radiation damage and the inability to invert coherent d...

We present a numerical spectroscopic study of visible and infrared laser radiation in a biological tissue. We derive a solution of a general two-dimensional time dependent radiative transfer equation in a tissue-like medium. The used model is suitable for many situations especially when the external source is time-dependent or continuous. We use a control volume-discrete ordinate method associa...

We present a method based on photon migration of extracting intrinsic fluorescence spectra from turbid media, using concomitantly measured fluorescence and reflectance. Intrinsic fluorescence is defined as fluorescence that is due only to fluorophores, without interference from the absorbers and scatterers that are present. Application to fluorescence spectra taken with tissue phantoms and huma...

Blood flow speed is an important functional parameter. Doppler ultrasound flowmetry lacks sufficient sensitivity to slow blood flow (several to tens of millimeters per second) in deep tissue. To address this challenge, we developed ultrasonically encoded photoacoustic flowgraphy combining ultrasonic thermal tagging with photoacoustic imaging. Focused ultrasound generates a confined heat source ...

By "listening to photons," photoacoustics allows the probing of chromosomes in depth beyond the optical diffusion limit. Here we report the photoacoustic resonance effect induced by multiburst modulated laser illumination, which is theoretically modeled as a damped mass-string oscillator and a resistor-inductor-capacitor (RLC) circuit. Through sweeping the frequency of multiburst modulated lase...

Achieving the stability of bone tissue in field dental implants is still most urgent and completely unsolved problem implantological practice. Modern ideas about biological principles structure functioning tissues periimplant zone are one significant factors ensuring crestal tissue. The soft-tissue component that forms basis complex at implant-suprastructure interface plays a key role protectin...