ECEN5341/4341Bioelectromagnetics Spring 2019 Frank S. Barnes Contact Info:             (303)492-8225       frank.barnes@colorado.edu, ECOT 433 the website. http://ecee.colorado.edu/~ecen4341/supplement.html http://ecee.colorado.edu/~ecen4341/5341 index.html Kim Newman at Kimberly.Newman@colorado.edu For web support.

INTRODUCTION OBJECTIVES: To explore the field of bioelectromagnetics and maybe to push the frontier a little bit. To have you become acquainted with the complexity of going from the physics through the chemistry to the biology and possible health effects to public policy for risk. To have you gain some experience in acquiring information from the literature and putting it into a useful form. OUTLINE OF THE COURSE A review of some of the electrical properties of biological materials and the problems of coupling electric and magnetic fields into them. A review of the physics of the effects of electric fields on biological systems at low frequencies A review of the physics of the effects of magnetic fields on biological systems A discussion of some possible health effects of these fields

INTRODUCTION A review of radio and microwaves The coupling of radio waves into a biological system Some physics of the interactions of RF on biological systems and some effects. A review of lasers and laser safety if time permits APPROACH TO THE SUBJECT Start with the physics at the simplest levels and work up through the layers of biological complexity. The scope of the problem is: From 10-12 seconds to generations. From electrons and atoms to the whole body. From DC to gamma rays The major part of the problem is our lack of understanding of the biology and the biochemistry

INTRODUCTION COURSE OPERATIONS: Assigned reading: "Handbook of Biological Effects of Electromagnetic Fields", 4th Edition, Edited by Ben Greenebaum and Frank Barnes. Also of interest: “The Physiology of Bioelectricity in Development, Tissue Regeneration, and Cancer” Edited Christine Pullar and other literature depending on your interests. Requirements. 1. Read and Work through a large part of  the material in both volumes of the Handbooks Biological Effects of Electromagnetic Fields 2. Review at least two new papers a week and bring in at least a one or two page review of them to class. Also be prepared to present your review to the class. The first assignment will be to read the hand book preface and first part of the introduction for Friday. The second will be to find papers on the measurement of the electrical properties of biological materials and related it to the material in the Handbook. You will need to write up each paper you read at the level of about one page per paper. I want critical comments on the papers strengths and weakness as well as brief review of the important results. Also you should be prepared to present some of the most interesting result in class. It is likely that with 15 students you will be asked to make presentation nearly every week. 3. Two term papers. These papers may be presented to the class and discussed. They may also be handed back for farther development. 4. Two  one hour tests and a final. The course will be flexible in the choice of material to be covered to match the interests of the class.

Some History 1. Debate on Thermal vs. Non-thermal Health effects from radar goes back to at least 1960s. 2. Wertheimer, N., and E. Leeper.1979. 3. Cordless phones, cell phone, WiFi 4. In all cases there are problems in going from the physics through the chemistry to the biology to possible health effects.

Some Uses of Electric and Magnetic Fields 1. Use of Electric and Magnetic Fields as Patent medicine 2. Use for repairing nonunion bone breaks 3. Depression 4. Electro surgery 5. Stimulating Nerves 6. Blocking Pain 7. Imaging, MRI, Microwaves, Optics

Research topics that we might include: Can we treat electromagnetic fields as a source of biological stress? What do we mean by stress? What are the effects of small periodic temperature variations on biological systems? In particular what might they do to the brain and nerve cells? What are the differences between cancer and normal tissues that can be observed with electromagnetic fields from DC to light? Can we build an optical fiber system that will detect cancer that will fit in a needle? Can we change growth patterns with electric or magnetic fields? Are there some ways to use electric or magnetic fields in therapy? What are the effects of electric and magnetic fields on the immune system? How are Type-B Cytochromes and Free Radicals effected by electric and magnetic fields. What are the effects of DC Magnets on pain? NH Abrami 5G Health Environment Bill Jan 2019 How do electric forces on molecules compare with mechanical stresses at membranes in different directions?

Definitions of Electric Fields Define the electric field E by Where F is the force and q is the charge on the particle The force between two point charges is given by Coulomb’s Law Where ε is the dielectric constant and r is the separation between charges.

Magnetic Flux Density We can define the magnetic flux density B in terms of the time rate of change of charge or in terms of the velocity of the charge by the Lorentz force law. Where Static Case N S N S For a magnetic Dipole

Magnetic Field The magnetic field is defined from Maxwell’s equations and is related to the magnetic flux density by Where µ is the magnetic permeability and is magnetic Fields The magnetic field around a current carrying wire is given by The induced voltage V is given by The magnetic field from a short wire is given By : Ampere’s Law

Radiation . The power W radiated from a charged q is given by Where a is the acceleration and c is the velocity of light For a short wire power radiated is given by η Is the impedance of free space The difference between induced fields and radiation depends on the dimensions of the device and the wave length. At 60Hz the wavelength is given by The radiation resistance for short linear dipoles of length l <<λ is given by The radiated power is given by