Commission K (Electromagnetics in Biology & Medicine) Activity Report

 - March, 2005 to June, 2005 -


July 15, 2005

Masao Taki and Tsukasa Shigemitsu


1.       Meeting

A. Domestic Meeting

(1)March 25-27, 2005: 44th Annual Meeting of Japanese Society for Medical and Biological Engineering,

Tsukuba, Japan (

(2) April 4-8, 2005: The 2005 IEEE International Magnetics Conference, Nagoya Congress Center, Nagoya

(3) August, 2008; BIOMAG2008, Sapporo, Japan


B. International Meeting

(1) March 1-5, 2005: UNESCO seminar and practical workshop on molecular and cellular mechanisms of biological effects of EMF. Yerevan, Armenia. Sponsored by WHO and European Office of Aerospace Research and Development (EOARD).

(2) May 16-18, 2005: ElectroMed 2005, Portland, Oregon,

(3) June 13-14, 2005: 10th International Advisory Committee (IAC) Meeting of the WHO International Electromagnetic Field Project, Geneva, Switzerland

     This tenth Meeting covers activities and outputs for the period June 2004 to June 2005. In the meeting, the following topics were presented; Research (Research review of the past year, Update on the INTERPHONE study etc.), Standards (WHO framework for developing EMF standards, update on the precautionary framework), Summary of WHO-sponsored workshops (Electrical hypersensitivity, Children and EMF et c.), Communication activities (WHO publications and website, Research database, world wide standards database et c), NIR activities, Occupational exposure to EMF fields (The EU directive, Managing EMF workplace exposures etc.)

   Details of this meeting can be found on homepage at:


(4) June 15-16, 2005: Base stations & wireless networks: exposures & health consequences. WHO, Geneva, Switzerland,

(5) June 19-24, 2005: 27th, Bioelectromagnetics, Joint Meetings of BEMS and EBEA, Dublin, Ireland.

(6) June 19, 2005: The XVIII International Symposium on Bioelectrochemistry and Bioenergetics, Coimbra, Portugal. http://www.bes-ise-2005.uc.p

(7) July 1, 2005: Coherence and Electromagnetic Fields in Biological Systems, Prague, Czech Republic.

(8) July 11-13, 2005: Applying precautionary measures to EMF public health policy. Ottawa, Canada.


2. Future meeting

A.   Domestic meeting

(1) July 21-22, 2005: 20th Annual Meeting of Japan Biomagnetism and Bioelectromagnetics Society, Osaka

(2) November 14-17, 2005: 9th Symposium on New Magneto-Science and 3rd open symposium on innovative utilization of strong magnetic fields. Yokohama.


B.   International meeting

(1)August 3-5, 2005: International Symposium on Antennas and Propergation, Seoul, Korea,

(2) September 12-16, 2005: The 4th International Seminar on Electromagnetics Fields and Biological Effects. Kunming, or

(3) September 19-21, 2005: EMC Europe Workshop 2005, Rome, Italy,

(4) September 26-30, 2005: South American regional meeting on health effects of EMF fields. Brazil.

(5) October 2-9, 2005: Electromagnetic fields and genotoxicity. The School of Bioelectromagentism,

(6) October 23-29, 2005: URSI 28th General Assembly, New Delhi.

(7) 30 October – 1 November, 2005: Workshop on Application of Proteomics and Transcriptions in EMF Research. Helsinki, Finland.

(8) November 5-6, 2005: European cancer prevention organization annual meeting, gMobile phones and cancer prevention.h. The Floreal Club Blanenberge, Belgium.

(9) November 14-18, 2005: WHO & Australian radiation protection society workshop. Melbourne, Australia.
















































4. Technical Trends


K1 Biological Effects of Electromagnetic Fields

K1.1 DC and ELF Electric Fields@

On dosimetry, Shimizu, et al. developed user-friendly software to visualize the ELF electric field exposed to a human body [Shimizu, 2003a]. It provides the distributions of the surface field and the current induced in the human body within a practical computation time using a regular personal computer. The GUI made the changes of body proportion and environmental conditions practically simple. On instrumentation, Yamashita, et al has developed a ring-type telemeter for the photoelectric pulse measurement [Yamashita, 2000a]. The variation in the autonomic nervous system could be measured and analyzed. They have also developed a telemetry technique to measure EEG and ECG at the subject exposed to strong ELF electric field. Since it makes unconstrained measurement possible, it is useful to evaluate the physiological change in field exposure [Yamashita, 2000b]

On cellular effects, Shimooka, et al. has pursued the possibility of immuno-modulation caused by the electric stimulation of the current induced in the body on field exposure [Shimooka, 2004]. They have reported the suppression effects of macrophage phagocytosis [Fujii, 20002; Kagawa, 2004], histamine release [Morita, 2002] and the generation of the reactive oxygen species [Tatebe, 2004].

Biological effects were evaluated with plants. Nitta, et al. has found that bean sprout has the better growth in the higher electric field in the range of 10-25kV/m [Kiatgamjorn, 2003]. Nitta, et al. have found the growth rate of ice plants in the electric field of 28.5kV/m than the no field condition [Rotcharoen, 2003].

In the experiments with human subjects, Yamashita, et al. exposed ELF electric field on the skin surface of the human forearm, and measured the physiological changes such as the skin temperature, the surface blood flow and the blood volume in the arm. In the local field exposure, the increases in these parameters were observed. The results of these experiments suggested that this response was controlled by the central nervous system [Yamashita, 2004]. Shimizu, et al. analyzed the body hair movement caused by ELF electric field exposure. Through theoretical and experimental study, the mechanism of field perception was explained in detail. In this study, the cause of the seasonal variation of the perception threshold was clarified [Shimizu, 2003b, 2004]. Ohsaki, et al. has attempted to apply the strong field exposure to therapeutic use. Using the apparatus approved by a government, they performed various fundamental studies and clinical tests. In objective parameters, the alleviation of pain in various muscles was demonstrated [Ohsaki, 2004] [Shimizu].



Chalise.P.R., M.S.Rahman, H.Ghomi, Y.Hayashi, M.Watanabe and A.Okino [2004], gBacterial inactivation using low-energy pulsed-electron beam.h IEEE Transaction on Plasma Science, vol.32, pp.1532-1539


Fujii,I., T.Shimooka,Y.Morita and K.Shimizu [2002], gExperimental verification for the effect of capacitively coupled electrostimulation on macrophagefs endocytosis,h Technical Report of IEICE,MBE-2001-176, pp.97-102. (In Japanese)


Ikeya.M., Y.Emoto, H.Asahara and C.Yamanaka [2004], gAir bubble movements and animal behavior as responses to electromagnetic signals before earthquakes: Network monitoring of catfish.h Proceedings of EMCf04 Sendai, 3E1-3, pp.749-752


Hasegawa.H and T.Tamura [2003], gDevelopment of sterilization technology by application of pulsed high.h J Institute of Electrostatics Japan, Vol.27, pp.117-122 voltage (In Japanese)


Harakawa.S., N.Inoue, A.Saito, F.Doge, H.Nagasawa and N.Suzuki [2004a], g60Hz electric field upregulates cytosolic Ca2+ level in mouse splenocytes stimulated by lectin,h Bioelectromagnetics, vol.25, pp.204-210


Harakawa.S., I.Takahashi, F.Doge and D.E.Martin [2004b], gEffect of a 50Hz electric field on plasma ACTH, glucose, lactate, and pyruvate levels in stressed rats,h Bioelectromagnetics, vol.25, pp.346-351


Harakawa.S., N.Inoue, A.Saito, F.Doge, H.Nagasawa and N.Suzuki [2004c], g60Hz electric field upregulates cytosolic Ca2+ level in mouse splenocytes stimulated by lectin.h Bioelectromagnetics 25 pp.204-210


Kagawa,M., T.Shimooka, T.Tatebe and K.Shimizu [2004], gChange of endocytic activity of macrophage by electrostimulaiton-Fundamental study for possible association of humoral factors,h Technical Report of IEICE, MBE2003-131, pp.19-24 (In Japanese)


Kiatgamjorn,P., W.Khan-ngern and S.Nitta [2003], gThe comparison of electric field intensity affects to the bean sprouts growing,h Proc.CEEM 2003, pp.142-147.


Kiatgamjorn.P., W.Khan-ngern and S.Nitta [2004], gElectric field direction affects on the growth of bean sprouts.h Proceedings of EMCf04 Sendai, 4D3-1, pp.885-888


Morita,Y., T.Shimooka, I.Fujii and K.Shimizu [2002], gEffect of ELF electrostimulation on histamine release from mast cells,h Technical Report of IEICE, MBE2001-175, pp.91-96 (In Japanese)


Ohsaki.K. and A.Hara [2004], gResearch on biological responses related to the effects of extremely low frequency electric fields,h Proceedings of EMCf04, Sendai, 4B2-3, pp.785-788.


Rotcharoen,T., W.JKhan-ngern and S.Nitta [2003], g The study of rice growing with the electromagnetic field effect stimulated 300kV switching substation,h Proc.CEEM 2003, pp.148-152.


Rotscaroen.T., P.Kerdonfag, W.Khan-ngren and S.Nitta [2004], gThe study of bending effect on the growth of the primary root of rice caused by electric field.h Proceedings of EMCf04 Sendai, 4D4-3, pp.901-904 


Sakae.M., A.Asakawa, K.Ikesue, T.Shindo, S.Yokoyama and M.Hara [2003], gEffects of different kinds of live trees and a tree model on discharge characteristics to an open wire and a nearby tree,h IEEJ Trans. PE, Vol.123, pp.60-67 (In Japanese)


Sato.M [2003], gInactivation of microorganisms by pulsed electric field,h J Institute of Electrostatics Japan, Vol.27, pp.106-110


Shimizu, K., F. Doge and K. Ohsaki [2003a], gDevelopment of user-friendly software to visualize ELF electric field exposed to human body,h Proc. of CEEM 2003, pp.122-125.


Shimizu.H.O. and K.Shimizu [2003b], gAnalysis of electric force exerted on human hair in ELF electric field exposure.h Trans.IEICE, Vol.J86-B, No.7, pp.1225-1233 (In Japanese)


Shimizu.H.O. and K.Shimizu [2004], gAnalysis of human perception of ELF electric fields.h Proceedings of EMCf04, Sendai, 4B2-2, pp.781-784


Shimooka,T., I.Fujii, M.Kagawa, T.Tatebe and K.Shimizu [2004], h Effect of ELF electrostimulation on function of macrophage.h Proceedings of EMCf04 Sendai, 4B2-1, pp.777-780


Shindo.T., A.Asakawa, H.Honda, M.Sakae and S.Tanaka [2003], gNecessary clearance to prevent side flashes.h IEEJ Trans. PE, Vol.123, pp.90-974 (In Japanese)


Tatebe,T., T.Shimooka, M.Kagawa and K.Shimizu [2004], gEffect of ELF electrostimulation on reactive oxygen generation of macrophage.h Technical Report of IEICE, MBE2003-130, pp.13-18 (In Japanese)


Taki.M., Y.Suzuki and K.Wake [2003], gDosimetry considerations in the head and retina for extremely low frequency electric fields.h Radiation Protection Dosimetry, vol.106, pp.349-356


Yamashita.M., M.Sugano and K.Shimizu [2000a], gPhotoelectric pulse measurement with a ring-type telemeter and analysis on the variation in autonomic nerve activity.h Proc of BPES 2002, pp.325-328 (In Japanese)


Yamashita.M., K.Ohsaki and K.Shimizu [2000b], gDevelopment of biotelemetry technique for EEG/ECG measurement in a strong ELF electric field.h IEEJ, vol.122-C, pp.1589-1594 (In Japanese)


Yamashita,M., K.Ohsaki adnK.Shimizu [2004], gAnalysis of physiological changes caused by local exposure of ELF electric field.h Technical Report of IEICE. (In Japanese)

Yoshimura.N., M.Suzuki and K.Mitobe [2003], gThe research on the sterilization in the a-thermal process.h J Institute of Electrostatics Japan, Vol.27, 111-116p (In Japanese)


K1.2 DC Magnetic Fields on cells and genetics

In several kinds of microbial species, example of reports of the positive effect of DC magnetic field have been confirmed. SoxR on Escherichia coli in which there are too many examples of reports until now. Variant sodAsodB [Zhang et al.,2003] which reports rising, since the mutagenesis frequency has it by 5 or high magnetic field of 9 teslas in the double mutant. Saccharomyces cerevisiae with the paper which found the rise in expression strength of several kinds genes of by the high magnetic field of 14 teslas [Ikehata, 2003]. Rhodobacter sphaeroides [Utsunomiya, 2003] in which the production of porphyrin reports the increase at 5.3 times in the high magnetic field of 0.3 teslas. There are some inhibition of multiplication by 0.1mT magnetic field, example of reports of the effect by magnetic field to 0.51mT conidium formation rate besides on 3 kinds of Plant pathogenic fungi (Ikehata and Miyakoshi).

There are several studies to determine the mutagenicity by exposure to strong static magnetic fields. Takashima et al. reported dose response relationship between magnetic field density and its mutagenicity using DNA repair-proficient and -deficient strains of fruit fly Drosophila melanogaster. It was found that exposure to 2, 5 or 14 T fields for 24h caused a statistically significant enhancement in somatic recombination frequency in the post-replication repair deficient flies, whereas the frequency remained unchanged in the nucleotide excision repair deficient flies and in the DNA repair-proficient flies after exposure.  An increase linearly dependent on the flux density was observed between 0.5 T and 2 T, while it was saturated at exposure levels over 2 T. These findings suggest that exposure to high density magnetic fields induce somatic recombination in Drosophila, and that the dose-response relationship is not linear.

Zhang et al. using an Escherichia coli mutation assay to assess the mutagenic effects of strong magnetic filed. The mutation frequency was significantly increased by the static magnetic field exposure in soxR and sodAsodB mutants, which are defective in defense mechanisms against oxidative stress. In addition, the expression of superoxide-inducible socS:: lacZ fusion gene was stimulated 1.4- and 1.8-fold in E.coli when exposed to 5 and 9 T, respectively. These results indicate that strong static magnetic field induces mutations through elevated production of intracellular superoxide radical in E.coli.(Ikehata and Miyakoshi).




Hashimoto.Y., M.Kawasumi and M.Saito [2004], gEffect of static magnetic field on cell migration.h IEEJ Trans EIS, Vol.124, pp.1719-1724


Ikehata.M, M.Iwasaka, J.Miyakoshi, S.Ueno and T.Koana [2003], gEffects of intense magnetic fields on sedimentation pattern and gene expression profile in budding yeast,h J.Appl.Phys, vol.93, pp.6724-6726


Ikehara.M., Y.Takashima, H.Takeyama, M.Iwasaka, S.Ueno, T.Matsunaga, J.Miyakoshi and T.Koana [2003], gEstimation of mutagenicity and perturbative effects by exposure to strong magnetic field,h Proceedings of the WHO 3rd International EMF Seminar in China, pp.96-98, Oct


Nagy.P and G.Fiscl [2004], gEffect of static magnetic field on growth and sporulation of some plant pathogenic fungi,h Bioelectromagnetics, vol.25, pp.316-318


Nakahara,T., H.Yaguchi, M.Yoshida and J.Miyakoshi [2002] gEffects of exposure of CHO-k1 cells to a 10 T static magnetic fieldh. Radiology, vol.224, pp.817-822.


Okano.H and C.Ohkubo [2003], gEffects of static magnetic fields on plasma levels of angiotensin II and aldosterone associated with arterial blood pressure in genetically hypertensive rats.h Bioelectromagnetics vol.24, pp.403-412


Takashima.Y., J. Miyakoshi, M. Ikehata, M. Iwasaka, S. Ueno and T. Koana, gGenotoxic effects of strong static magnetic fields in DNA-repair defective mutants of Drosophila melanogaste,h Journal of Radiation Research (in press)


Utsunomiya.T et al. [2003] J.Biosci.Bioeng, vol.95, pp.401-404

Zhang.Q.M., M.Tokiwa, T.Doi, T.Nakahara, P.W.Chang, N.Nakamura, M.Hori, J.Miyakoshi and S.Yonei [2003], gStrong static magnetic field and the induction of mutations through elevated production of reactive oxygen species in Escherichia coli soxR,h Int.J.Radiat.Biol., vol.79, pp..281-286.


4.1.2 Magnetic orientation- Agarose and Microorganisms

Bull sperm and paramecium cilium are oriented in a strong static magnetic field. An anisotropic diamagnetic susceptibility of microtubules which are one of their components contributes it [Higashi].
  Magnetic fields of 5-10T were applied to agarose molecules to obtain the random, the planar and the axial gels. As a result, the electrophoretic velocity depended on the gel structure as well as the size and structure of DNAs. The magnetically ordered agarose gels can be used for a new separation method of DNAs at a high resolution [Higashi, Yamaguchi and Iwasaka].



Emura.R., T.Takeuchi, Y.Nakaoka and T.Higashi [2003], gAnalysis of anisotropic diamagnetic susceptibility of a bull sperm,h Bioelectromagnetics., vol.24, pp.347-355


Higashi. T., R.Emura and T.Takeuchi [2002], gEffects of on-and-off static magnetic field on fibrinolysis,h Biological Effects of Electromagnetic Fields, Proceeding of 2nd International Workshop, 790-797p


Ichioka.S., M.Minegishi, M.Iwasaka, M.Shibata, T.Nakatsuka and J.Ando [2003], gSkin temperature changes induced by strong static magnetic field exposure,h Bioelectromagnetics, vol.24, pp.380-386


Iwasaka.M., J.Miyakoshi and S.Ueno [2003a], gMagnetic field effects on assembly pattern of smooth muscle cells,h In Vitro Cell Biol-Animal, vol.39


Iwasaka.M., K.Yamamoto, J.Ando and S.Ueno [2003b], gVerification of magnetic field gradient effects on medium convection and cell adhesion,h J Applied Physics, vol.93, pp.6715-1717


Iwasaka.M and S.Ueno [2003c], gDetection of intracellular macromolecule behavior under strong magnetic fields by linearly polarized light.h Bioelectromagnetics, vol.24, pp.564-570


Iwasaka.M and S.Ueno [2003d], gDetection of intracellular macromolecule behavior under strong magnetic field by linearly polarized light,h Bioelectromagnetics, vol.24, pp.564-570


Sungkhaphun.P, W.Khan-ngren and S.Nitta [2004], gThe study of magnetic field intensity and time@variation affect on the rice growth.h Proceedings of EMCf04 Sendai, 4D3-1, pp.881-884


Takeuchi. T., Y.Nakaoka, R.Emura.and T.Higashi [2002], gDiamagnetic orientation of bull sperms and related materials in static magnetic fields,h J. Phys. Soc. Japan., vol.71, 363-368p


Takeuchi.M., M.Sekino, N.Iriguchi and S.Ueno [2005], gT2 relaxation and diffusion of collagen gel oriented.h J Magn Soc Japan, vol.29, pp.347-350 (In Japanese)Chiba.A and M.Inase [2003], gPhosphate metabolites in muscular contraction caused by magnetic stimulation,h Bioelectromagnetics, vol.24, pp.366-371


Yamaguchi.M and I. Yamamoto [2004]: Proc. Int. Workshop on Materials Analysis and Processing in Magnetic Fields, March 17-19,Tallahassee, USA


K1.3 DC and ELF Magnetic Field


K1.3.1 In vivo studies

Human and AnimalidAvہj



Kezuka.E., M.Masada, T.Shigemitsu and M.Kato [2004], gThe vertically polarized magnetic field has no effect on the content of pteridine in mouse liver,h Asia-Pacific Radio Science Conference Proceedings, pp.450-451

Kezuka.E., M.Masada, T.Shigemitsu and M.Kato [2005], gEffects of 50Hz magnetic field exposure on secretion of pteridine in mice is dependent on field polarization.h 2005 BioEM Meeting, Dublin


Kobayashi.M., N.Soda, T.Miyo and Y.Ueda [2004], gEffects of combined DC and AC magnetic fields on germination of hornwort seeds.h Bioelectromagnetics vol.25, pp.552-559


Kurokawa.Y., H.Nitta, H.Imai and M.Kabuto [2003a], gAcute exposure to 50Hz magnetic fields with harmonics and transient components: lack of effects on nighttime hormonal secretion in men,h Bioelectromagnetics, vol.24, pp.12-20


Kurokawa.Y., H.Nitta, H.Imai and M.Kabuto [2003b], gCan extremely low frequency alternating magnetic fields modulate heart rate or its variability in humans?h Autonomic Neuroscience: Basic and Clinical, vol.105, pp.53-61


Mizoue.T., Y.Onoe, H.Moritake, J.Okamura, S.Sokejima, and H.Nitta [2004], gResidential proximity to high-voltage power lines and risk of childhood hematological malignancies.h J Epidemiology, vol.14, pp.118-123


Oda.T and T.Koike [2004], gMagnetic field exposure saves rat cerebellar granule neurons from apoptosis in vitro.h Neuroscience Letters., vol.365, pp 83-86


Okano.H and C.Ohkubo [2003a], gAnti-stressor effects of whole body exposure to static magnetic field on pharmacologically induced hypertension in conscious rabbits,h Bioelectromagnetics, vol.24, pp.139-147


Okano.H and C.Ohkubo [2003b], gEffects of static magnetic fields on plasma levels of angiotensin II and aldostrone associated with arterial blood pressure in genetically hypertensive rats,h Bioelectromagnetics vol.24, pp.403-412


Okano.H., H.Masuda and C.Ohkubo [2005], gDecreased plasama levels of nitric oxide metabolites, angiotesin II, and aldosterone in spontaneously hypertensive rats exposed to 5mT static magnetic field.h Bioelectromagnetics vol.26, pp.161-172


Shigemitsu.T [2004], gBiological and health effects of ELF electromagnetic field.h Proceedings of EMCf04 Sendai, 4B1-1, pp.765-768


Sawaguchi.Y., K.Kimura, K.Misawa and J.Arisawa [2004], gEffects of 50Hz magnetic field exposure on the body color and the urine quantity of goldfish.h Proceedings of EMCf04 Sendai, 4B1-3, pp.773-776


Ushiyama.A And C.Ohkubo [2004a], gAcute effects of low-frequency electromagnetic fields on leukocyte-endothelial interactions in vivo,h In Vivo, vol.18, pp.125-132


Ushiyama.A., H.Masuda, S.Hirota and C.Ohkubo [2004b], gSubchronic effects on leukocyte-endothelial interactions in mice by whole body exposure to extremely low frequency electromagnetic fields.h In Vivo vol.18, pp.425-432


Ushiyama.A., Y.Suzuki, H.Masuda, S.Hirota, M.Taki and C.Ohkubo [2004c], gEffects of continuous whole-body exposure to 50Hz electromagnetic fields with repetitive transient magnetic fields on the intramicrovascular leukocyte behavior in mice. Asia-Pacific Radio Science Conference Proceedings pp.424-426


Yamaguchi.S., M.Ogiue-Ikeda, M.Sekino and S.Ueno [2005], gEffects of transcutaneous magnetic stimulation on tumor and immune functions in mice.h J Magn Soc Japan., vol.29, pp.360-363 (In Japanese)


Yano.A., Y.Ohashi, T.Hirasaki and K.Fujiwara [2004], gEffects of a 60Hz magnetic field on photosynthetic Co2 uptake and early growth of radish seedlings.h Bioelectromagnetics vol.25, pp.572-581


Yokoi.S., M.Ikeya, T.Yagi and K.Nagai [2003], gMouse circadian rhythm before the Kobe earthquake in 1995,h Bioelectromagnetics, vol.24, pp.289-291


K1.3.2 In Vitro studies


Cell; proliferation, cell cycle, mutationi{zj

No or very little effects of ELF electromagnetic field were found on basic cellular behaviors (proliferation, survival and cell cycle). Exposure to a high-density ELF electromagnetic field increased mutation and chromosomal aberration dose-dependently.  Such a result was more significant under a combined exposure with external factors. Results of molecular biological analysis for its mechanism revealed that a response to an ELF electromagnetic field had an effect on the signal transduction system that was involved with intracellular calcium and protein kinase (Miyakoshi).



Fu-Rong Tian., T.Nakahara, M.Yoshida, N.Honda, H.Hirose and J.Miyakoshi [2002], gExposure to power frequency magnetic fields suppresses X-Ray-induced apoptosis transiently in Ku80-deficient xrs5 cells.h Biochemical and Biophysical Research Communications, vol.292, pp.255-261


Guig-Rong Ding., T.Nakahara, Fu-Rong Tian, Yao Guo and J.Miyakoshi [2001a], gTransient suppression of X-ray-induced apoptosis by exposure to power frequency magnetic fields in MCF-7 cells.h Biochemical and Biophysical Research Communications, vol.286, pp.953-957


Guig-Rong Ding., K.Wake, M.Taki and J.Miyakoshi [2001b], gIncrease in hypoxanthine-guanine phosphribosyl transferase gene mutations by exposure to electric field,h Life Sciences, vol.68, pp.1041-1046


Guig-Rong.Ding., T.Nakahara and J.Miyakoshi [2002], gExposure to power frequency magnetic fields and X-rays induces GAP-43 gene expression in human glioma MO54 cells.h Bioelectromagnetics, vol.23, pp.586-591


Guig-Rong Ding., T.Nakahara and J.,Miyakoshi [2003], gInduction of kinetochore-positive and kinetochore-negative micronuclei in CHO cells by EMF magnetic field and/or X-rays.h Mutagenesis. vol.18, pp.439-443


Guig-Rong Ding, T.Nakahara, H.,Hirose, S.koyama and J.Miyakoshi [2004], gELF magnetic fields promote H2O2 -induced cell death in HL-60 cells.h International Journal of Radiation Biology., vol.80, pp.317-324


Koyama.S., T.Nakahara, H.Hirose, Gui-Rong Ding, Y.Takashima, Y.Isozumi and J.Miyakoshi [2004a], gELF Electromagnetic fields increase hydrogen peroxide (H2O2)-induced mutations in pTN89 plasmids.h Mutation Research., vol.560, pp.27-32


Koyama.S., T.Nakahara, H.Hirose, Y.Takashima, Y.Isozumi and J.Miyakoshi [2004b], gCombined effects of extremely low frequency electromagnetic fields (ELFMFs) and X-rays or H2O2 on mutation in pTN89 plasmids.h Asia-Pacific Radio Science Conference Proceedings pp.414-417 


Miyakoshi.J [2004], gCellular and molecular effects of electromagnetic fields,h Proceedings of EMCf04 Sendai, 4B1-2, pp.769-772


Sakurai.T., A.Satake, S.Sumi, K.Inoue and J.Miyakoshi [2004a], gAn extremely low frequency magnetic field attenuated insulin secretion from the insulinoma cell line, RIN-m,h Bioelectromagnetics vol.25, pp.160-166


Sakurai,T., S.satake, S.Sumi, K.Inoue, N.Nagata, Y.Tabata and J.Miyakoshi [2004b] gThe efficient prevasculariation induced by fibroblast growth factor 2 with collagen coated-device improves the cell survival of a bioartificial pancreash. Pancreas, vol.28, pp.70-79.


Cell; Time-varying 1.7 T fields, ion channels, bone cell


Exposure to a time-varying magnetic field (maximum flux density of 1.7T) inhibits K+ influx via Ca2+-dependent K+ channel and an increase in intracellular Ca2+ concentration ([Ca2+]i) of HeLa cells incubated in high K+ medium [Ikehara, 2002]. Addition of Ca2+ ionophore (ionomycin) to the high K+ medium increase [Ca2+]i to the level of control cells, regardless of exposure to the magnetic field. But the inhibition of K+ uptake by exposure to the magnetic field is not restored by addition of the ionophore. This strong time-varying magnetic field (maximum of 1.51T) also inhibits a transient increase in [Ca2+]i in bovine adrenal chromaffin cells induced by bradykinin (BK) in a Ca2+-free medium [Ikehara, 2002]. The exposure does not affect BK induced production of inositol 1,4,5 trisphosphate (IP3). Inhibition of the BK-induced increase in [Ca2+]i by exposure for 30 min is mostly recovered 1 hr after exposure ended. Our results reveal that the magnetic field exposure inhibits Ca2+ release from intracellular Ca2+ stores. Moreover, effects of exposure to a 50Hz magnetic field (maximum of 41.7 to 43.6mT) on the membrane structures of living HeLa cells were studied using attenuated total reflection infrared spectroscopy [Ikehara, 2003]. Exposure to the ELF magnetic field has reversible effects on the N-H inplane bending and C-N stretching vibrations of peptide linkages the secondary structure of -helix and sheet in cell membrane proteins.

On the other hand, in cultured osteoblast-like cells (MC3T3-E1), exposure to ELF magnetic field (60Hz, 3.0,T) for 3 days, both collagen and non-collagen protein content by multispectral imaging method, increased in the cells at peripheral; regions of culture dish than that at central regions of same dish. The treatment of IGF increased in collagen content at the peripheral cells for 17 days culture. But the additive effects of the exposure and IGF treatment were not observed [Yamaguchi, 2004].

ALP activity was increased significantly by the exposure alone or by combined with NGF treatment. These results indicate that the mechanisms of differentiation related to IGF and NGF in the osteoblasts were altered by the magnetic fields of extremely low frequency [Hosokawa, 2004]



Ikehara.T., K.H.Park, H.Yamaguchi, K.Hosokawa, K.Yoshizaki, H.Miyamoto, K.Aizawa and Y.Kinouchi. [2000], gEffects on Rb+ (K+) uptake of HeLa cells in a high K+ medium of exposure to a switched 1.7 tesla magnetic field.h Bioelectromagnetics vol.21, pp.228-237


Ikehara.T., K.H.Park, H.Yamaguchi, K.Hosokawa, H.Houchi, M.Azuma, K.Minakuchi, H.Kashimoto, M.Kitamura, Y.Kinouchi, K.Yoshizaki. and H.Miyamoto [2002], gEffects of a time-varying strong magnetic field on release of cytosolic free Ca2+ from intracellular stores in cultured bovine adrenal chromaffin cells.h Bioelectromagnetics, vol.23, pp.505-515


IkeharaT., H.Yamaguchi, K.Hosokawa, H.Miyamoto and K.Aizawa [2003], gEffects of ELF magnetic field on membrane protein structure of living HeLa cells studied by Fourier transform infrared spectroscopy,h Bioelectromagnetics, vol.24, pp.457-464


Hosokawa.K., H.Yamaguchi, T.Ikehara, H.Shichijo, M.Kitamura, K.Yoshizaki, Y.Kinouchi,  H.Miyamoto and K.Aizawa [2004], gEffects of ELF magnetic fields on signal for differentiation of cultured osteoblast-like cell by ImSpector system,h Jpn J Physiol, vol.53, S141


Yamaguchi.H., K.Hosokawa, H.Shichijo, M.Kitamura, A.Soda, T.Ikehara, Y.Kinouchi, K.Yoshizaki, H.Miyamoto and K.Aizawa [2004], gEffects of ELF magnetic fields on signal for differentiation of cultured osteoblastic cells by multispectral imaging system,h BEMS Abstract Book, 26th Annual Meeting, 216p


M1.3.3 other studies

Mutation in yeastsir[j

Takashima et al. reported that the effect of ELF magnetic fields on the DNA damage repair process, the gene conversion frequency and cell cycle kinetics in a DNA repair-proficient and nucleotide excision repair (NER)-deficient strain of diploid yeast Saccharomyces cerevisiae. DNA repair- or NER-deficient cells were irradiated with sub-lethal doses of ultraviolet light (UV) radiation followed by exposure to 50 Hz magnetic fields up to 30mT for 48 h. After exposure, gene conversion rate was increased by the combined exposure in DNA repair-proficient cells, whereas it remained unchanged between UV alone and the combined exposure in NER-deficient cells. The UV-induced G1 arrest was inhibited by exposure to 30mT ELF magnetic fields in both repair-proficient and -deficient cells. The results suggest that exposure to high-density (30 mT) ELF magnetic field decreases the efficiency of NER by suppressing G1 arrest, which in turn led to enhancement of the UV-induced gene conversion [Ikehata].

  Moreover, there are several fundamental research activities to clarify ELF or combined fields with static and ELFs.




Ikehara.T., H.Yamaguchi, K.Hosokawa, H.Miyamoto and K.Aizawa [2003], gEffects of ELF magnetic field on membrane protein structure of living HeLa cells studied by Fourier transform infrared spectroscopy,h Bioelectromagnetics, vol.24, pp.457-464


Ikehata.M., Y. Takashima, Y. Suzuki, H. Shimizu, J. Miyakoshi and T. Koana [2001], gExposure to a power frequency magnetic field (50 Hz, 40 mT) did not cause point mutation in bacteria.h Environ. Mut Res., vol.23, pp.215-222


Ikehata.M., M.Iwasaka, T.Nagai,, M.Taki and T.Koana [2004a], gEstimation of biological effects of complex environmental magnetic fields with various frequency components,h Proceedings of the ICNIRP/WHO International NIR Workshop and URSI Symposium, May


Ikehata.M., Y.Takashima, J.Miyakoshi and T.Koana [2004b], gEstimation of biological effects of extremely low frequency magnetic fields,h 11th International Congress of the International Radiation Protection Association, May


Ikeda.K., Y.Shnmura, H.Mizoe, H.Yoshizawa, A.Yoshida and H.Hirose [2003], gNo effects of extremely low frequency magnetic fields found on cytotoxic activities and cytokine production of human peripheral blood mononuclear cells in vitro,h Bioelectromagnetics, vol.24, pp.21-31


Kobayashi.M., N.Soda, T.Miyo and Y.Ueda [2004], gEffects of combined DC and AC magnetic fields on germination of hornwort seeds,h Bioelectromagnetics, vol.25, pp.552-559


Mizoue.T., Y.Onoe, H.Moritake, J.Okamura, S.Sokejima and H.Nitta [2004], gResidential proximity to high-voltage power lines and risk of childhood hematological malignancies,h J Epidemiology, vol.14, pp.118-123p


Sakurai.T., A.Satake, S.Sumi, K.Inoue and J.Miyakoshi [2004], gAn extremely low frequency magnetic field attenuates insulin secretion from the insulinoma cell line, RIN-m,h Bioelectromagnetics, vol.25, pp.160-166


Takashima.Y., M. Ikehata, J. Miyakoshi and T. Koana [2003], gInhibition of UV-induced G1 arrest by exposure to 50 Hz magnetic fields in repair-proficient and -deficient yeast strains.h Int J Radiat Biol., vol.79, pp.919-924


K1.4 IF Magnetic fieldiRA؁Adj

  WHO defines the intermediate frequency (IF) region of the EMF spectrum as being between 300Hz to 10MHz. Compared to ELF and RF fields, little research has been done of the effects of IF fields. There are two reports on the biological effects of IF magnetic fields. Haga et al. used a highly sensitive mutagenesis assay method (umu system) to evaluate the direct impact of exposure to 20kHz, 60T for DNA destruction gene mutation [Haga, 2004]. This exposure experiment induced bacterial umu DNA repair response in one experimental case. Tachi et al. also investigated whether IF magnetic field (20kHz, 0.5mT, 1mT) induce the DNA damage and physiological abnormality in bacterial cells containing bacteriophage [Tachi, 2005]. After about 4 and 8 hourfs exposure, this result suggests IF magnetic fields induce physiological damage in bacterial cells. Further studies are needed (Yamazaki and Suzuki).



Haga.A., Y.Kumagai, H.Matsuki and G.Endo [2004], gEvaluation of damage in DNA molecules by very low frequency magnetic fields using bacterial cells with bioluminescence gene.h Proceedings of EMCf04 Sendai, 4D4-2, pp.897-900


Tachi.S, M.Kakikawa, S.Hashimoto, M.Iwahara and S.Yamada [2005], gEffects on bacterial cells of exposure to very-low-frequency magnetic fields.h J Magn Soc Japan., vol.29. pp.356-359

K.1.5 RF and Microwaves – Animal 

Learning and Memory Study

Effects of exposure to electromagnetic waves (EMW) used in cellular phones on learning and memory processes were examined in Sprague-Dawley rats using a carousel type exposure system [Tsurita, 2000 and T-maze [Yamaguchi, 2003]. This study suggests that the exposure to a TDMA field at levels about four times stronger than emitted by cellular phones does not affect the learning and memory processes when there are no thermal effects 



Jarupat.S., A.Kawabata, H.Tokura and A.Borkiewicz [2003], gEffects of the 1900MHz electromagnetic field emitted from cellular phone on nocturnal melatonin secretion,h J Physiol Anthropol, vol.22, pp.61-63


Kojima.M., I.Hata, K.Wake, S.Watanabe, Y.Yamanaka and Y.Kamimura [2004], gInfluence of anesthesia on ocular effects and temperature in rabbit eyes exposed to microwaves,h Bioelectromagnetics, vol.24, pp.28-233


Tsurita.G., H.Nagawa, S.Ueno, S.Watanabe and M.Taki [2000], gBiological and morphological effects on the brain after exposure of rats to a 1439 MHz TDMA field,h Bioelectromagnetics, vol.21, pp.364-371


Yamaguchi.H., G.Tsurita, S.Ueno, S.Watanabe, K.Wake, M.Taki and H.Nagawa [2003], g1439MHz pulsed TDMA fields affects performance of rats in a T-maze task only when body temperature is elevated,h Bioelectromagnetics, vol.24, pp.223-230


RF-cell ({z)


Genotoxic effect of high frequency electromagnetic field (HFFMF) at 2.45GHz with a wide range of specific absorption rates (SARs) was examined in cultured cells. The micronucelus (MN) frequency of cells exposed to a HFEME at SAR of up to 50 W/kg was not different to that in sham-exposed cells, while those at SARs of 100 and 200 W/kg were significantly higher than in the sham-exposed controls. An increase in SAR causes a rise in temperature and this may be connected to the increase in MN formation generated by exposure to HFEMF. Effect of HFEMF on DNA damage was also examined using alkaline comet assay method. There was no significant difference in the tail moments between HFEMF- and sham-exposed groups. This finding suggests that exposure to HFEMF does not cause DNA strand breaks even at a SAR of 100 W/kg. For the gene expression, effect of HFEMF on the synthesis of heat shock protein 70 (Hsp70) was examined. Exposure to a HFEMF induced hsp70 expression at a high SAR of more than 20 W/kg but not at 5 W/kg in human glioma cells. In addition, there were no significant differences in Hsp27 and Hsp70 expressions between RF (1950 MHz)-exposed and sham-exposed cells at a SAR of lower than 10 W/kg. However, exposure to the RF field at 10 W/kg decreased the protein level of phosphorylated Hsp27 (78Ser) significantly.




Fu-Rong Tian., T.Nakahara, K.Wake, M.Taki and J.Miyakoshi [2002], gExposure to 2.45GHz electromagnetic fields induces hsp70 at a high SAR of more than 20W/kg, but not at a lower SAR of 5W/kg, in human glioma MO54 cells,h International Journal of Radiation Biology, vol.78, pp.433-440


Koyama.S., T.Nakahara, K.Wake, M.Taki, Y.,Isozumi and J.Miyakoshi [2003], gEffects of high frequency electromagnetic fields on micronucleus formation in CHO-K1 cells,h Mutation Research, vol.541, pp.81-89


Koyama.S., Y.Isozumi, Y.Suzuki, M.Taki and J.Miyakoshi [2004], gEffects of 2.45GHz electromagnetic fields with wide range of SARs on micronucleus formation in CHO-K1 cells.h The Scientific World Journal. vol.4, pp.29-40


Miyakoshi.J., M.Yoshida, Y.Tarusawa, T.Nojima, K.Wake and M.Taki [2002], gEffects of high-frequency electromagnetic fields on DNA strand breaks using Comet assay method,h Electrial Engineering in Japan, vol.141, pp.9-15


Miyakoshi,J., K.Takemasa, Y.takashima, G.-R.Ding, H.Hirose and S.Koyama [2005] gEffects of exposure to a 1950 MHz radio-frequency field on expression of Hsp70 and Hsp27 in human glioma cellsh. Bioelectromagnetics, vol.26, pp.251-257.


K2 Tissue Properties, Materials, and Phantoms


K.2.1 Design Methods of the Electromagnetic Environmenti{j

In order to use the EM power effectively in dairy life without losing the safety in every respect, only the EM waves which are actually needed inside the living space should be transmitted into the space. A stratified construction material that is consisted of two low loss materials has been developed for satisfying such a demand. The new functional material can absorb more than 70 percent of the incident EM power at specific frequencies that are pre-designed according to the demand (Miyakawa).



Ishii.N., M. Miyakawa and K. Sakai: "Method for Achieving Electromagnetic Wave Absorption by Low-loss Stratified Construction Materials", IEEE Trans. EMC (in press).


Ishii.N., M. Miyakawa and K. Sakai [2003], gAnalysis and design on EM wave absorption by stratified construction materials – a case of vertically incident wave,h Proc. IEEE Symposium on EMC, pp.800-805


Miyakawa.M., K. Sakai, and N. Ishii [2001a], gSelective use of EM waves in the closed space constructed by traditional but new construction materials with various surface structures,h Proc. IEEE EMC International Symposium, 2, pp.794-798


Miyakawa.M., M. Shimada, N. Ishii, T. Saeki, and Y. Kanai [2001b], gModel-based permittivity measurement of construction materials by the standing wave method,h Proc. IEEE EMC International Symposium, 2, pp.1135-1140


Miyakawa.M and S. Hoshina [2002a], gA self-supporting gel phantom used for visualization and/or measurement of the three-dimensional distribution of SAR,h Proc. IEEE EMC International Symposium, 2, pp.809-814


Miyakawa.M., K. Yaguchi, N. Ishii, T. Saeki and Y. Kanai [2002b], gAccuracy improvement in permittivity measurement of construction materials by use of a model of the standing wave method in free space,h Proc. IEEE EMC International Symposium, 2, pp.671-676


Miyakawa.M., N. Komiyama and N. Ishii [2003], gQuick search for a permittivity value in model-based standing wave method used for construction material measurement,h Proc. 2003 IEEE Symposium on EMC, pp.372-377


Tamada.T., N. Ishii and M. Miyakawa [2003], gAnalysis on the standing wave method in free space using spectral domain approach,h Proc. IEEE Symposium on EMC, pp.759-764


K2.2 Tissue Properties- Bioelectromagnetics parametersinӁA㑺j

The radio frequency safety guideline compliance for mobile phones has been evaluated by measuring the specific absorption rate (SAR) in the phantom material. The electromagnetic properties of bio-tissues and phantom material need to be specified in order to achieve precise and accurate SAR measurements. Recently, there are many research activities focused on Liquid phantoms (Watanabe and Kamimura).




Fukunaga.K., S.Watanabe, Y.Yamanaka, H.Asou, Y.Ishi and K.Sato [2004a], gDielectric properties of liquid phantoms for evaluations of mobile phones,h Proceedings of EMC f04 SENDAI, 4B3-5, pp.805-808


Fukunaga.K., S.Watanabe and Y.Yamanaka [2004b], gDielectric properties of tissue-equivalent liquids and their effects on specific absorption rate.h IEE EMC, vol.46, pp.126-129


Kamimura.Y [2004], gHuman body impedance for contact current measurement in Japan,h Proceedings of EMC f04 SENDAI, 3B4-1, pp.585-588


Kato.H [2002], gPhantoms for electromagnetic waves in medical use,h IEICE Trans. J-85-B, pp.597-608 (In Japanese)


Kawai.H, et al [2002], gEffects of inaccurate electric constants of the tissue-equivalent phantom on the local SAR and the SAR distribution,h IEICE trans. J85-B, pp.619-630 (In Japanese)


Kuriyama.Y [2004], gLiquid materialfs complex permittivity measurement using a rectangular waveguide and a dielectric tube at 800 and 900MHz band,h Proceedings of EMC f04 SENDAI, 3C3-3, pp.645-648


Hashimoto, et al [2003], gA study on measurement of dielectric constant by free space transmission method at C band,h IEICE Trans. J86-B, pp.1089-1095 (In Japanese)


Ueda.N, et al [2002], gInfluence of through hole on liquid materialfs complex permittivity measurement using a rectangular waveguide and a dielectric tube,h Tec. Rep. of IEICE, EMCJ2002-80, pp.21-26 (In Japanese)


K2.3 Phantomsiɓj

Various phantoms for the SAR (Specific Absorption Rate) estimation have been studied. A real-shaped torso bust phantom is developed to achieve an accurate evaluation of the SAR in the head as well as the characteristics of an antenna for a mobile terminal placed close to the human body [Ito, 2004]. The shape and size of the torso bust phantom are based on the average Japanese youths in their twenties. Moreover, an abdomen phantom of pregnant women including the amniotic fluid and the fetus is developed to estimate the SAR in the fetus [Kawai, 2003, Ito, 2005]. The targeted frequency range of this phantom is the VHF band. The dielectric constants of the amniotic fluid and the fetus of rabbits were measured to determine the dielectric constants of the phantom. In addition, solid phantoms, whose targeted frequency range is up 3 to 6 GHz, are investigated [Ishido, 2004]. The phantoms can reproduce the electrical properties of human biological tissues in the range of 3 to 6 GHz without changing their compositions.

In IEICE Transactions, the special issue on phantom has been published, and a review concerning the tissue equivalent phantoms has been reported [Ito, 2002]. High-molecular gel phantom with high transparency and viscosity has been proposed to realize the evaluation of the three dimensional EM wavesfexposure using a micro-capsulated thermo-chromic liquid crystal [Sunaga, 2003; Baba, 2004a, 2004b; Fukunaga, 2004; Suzuki, 2004]. Moreover, the phantom test phantom for implantable medical device to estimate the impact from RF EMF has been presented [Ohshita, 2004] [Ito].



Baba.M., Y.Suzuki, A.Ishi, M.Taki, K.Fukunaga and S.Watanabe [2004a], gDevelopment of a transparency high molecular gel phantom for three-dimensional visualization of radio frequency electromagnetic power absorption with capsulate thermo-chromic liquid crystal.h Asia-Pacific Radio Science Conference Proceedings, pp.418-419


Baba.M., A.Ishi, Y.Suzuki, S.Watanabe and M.Taki [2004b], gVisualization of three-dimensional lectromagnetic power absorption using gel containing liquid crystal.h Proceedings of EMCf04 Sendai, 3B5-3, pp.605-608


Fukunaga.K., S.Watanabe, Y.Yamanaka, H.Asou, Y.Ishi and K.Sato [2004], gDielectric properties of liquid phantoms for evaluations of mobile phones.h Proceedings of EMCf04 Sendai, 4B3-5, pp.805-808


Ishido.R., T. Onishi, K. Saito, S. Uebayashi, and K. Ito [2004], gA study on the solid phantoms for 3-6 GHz and evaluation of SAR distributions based on the thermographic method,h Proceedings of 2004 International Symposium on Electromagnetic Compatibility, EMC'04 Sendai, 3B3-2, pp.577-580


Ito.K., H.Kawai and K.Saito [2002], gState of the art and future prospects of biological tissue-equivalent phantom.h Transaction on IEICE, vol.J85-B, n0.5, pp.582-596 (In Japanese).


Ito.K and H. Kawai [2004], gPhantoms for evaluation of interactions between antennas and human body,h Proceedings of URSI Symposium on Electromagnetic Theory, (Pisa, Italy), 2, pp.1104-1106


Ito.K., H.Kawai, M.Takahashi, K.Saito, T.Ueda, M.Saito, H.Ito, H.Osada, Y.Koyanagi and K.Ogawa [2005], gA simple abdomen phantom of pregnant women at VHF band.h Proceedings of USNC.URSI United States National Committee, Colorado, USA, K1-6, P.460, Jan.


Kawai.H., Y. Koyanagi, K. Ogawa, K. Saito, and K. Ito [2003], gA study on the evaluation of the electromagnetic exposure in the human fetus model at 150 MHz,h IEEE Antennas and Propagation Society International Symposium Digest (Columbus, USA), 3, pp.1087-1090


Ohshita.K., Y.Tarusawa, S.Uebayashi and T.Nojima [2004], gThe test phantom for implantable medical device to estimate the impact from RF EMF.h Proceedings of EMCf04 Sendai, 2B4-1, pp.341-344


Onishi.T and S.Uebayashi [2004], gThe influence of a phantom shell on SAR measurement in the higher frequency range (3-6GHz).h Proceedings of EMCf04 Sendai, 3B3-1, 573-576


Sunaga.T., H.Ikehira, S.Furukawa, M.Tamura, E.Yoshitome and T.Obata [2003], gDevelopment of a dielectric equivalent gel for better impedance matching for human skin,h Bioelectromagnetics, vol.24, pp.214-217


Suzuki.Y., M.Baba, M.Taki, K.Fukunaga and S.Watanabe [2004]. gNew method for visualizing three-dimensional electromagnetic power absorption by capsulate liquid crystal dispersed in transparency high-molecular gel phantom,h Annual Report Conference on Electrical Insulation and Dielectric Phenomena, pp.194-197


K3 Field Measurement, Dosimetry and exposure assessment

K.3.1 DC and ELF fieldsidARj


Several analyses have been conducted focusing on induced currents inside the human body. Chiba et al conducted calculations of induced currents for grounded and ungrounded simple homogeneous human model when exposed to vertical uniform electric field, using finite element method (FEM) [Chiba, 2004]. Matusmoto et al developed a method for the analysis of the induced current using two-step process achieved by combination of the surface charge method and the FEM [Matsumoto, 2004].

In the analysis of magnetically induced currents, non-uniformity of the fields has been an key issue especially when assessing compliance with existing guidelines. Kamimura et al calculated the induced currents in human head using both analytical formulae and numerical computations when exposed to magnetic fields produced by AC driven electric shaver, that represents localized magnetic dipole sources [kamimura, 2002, 2004]. Nishizawa et al introduced equivalent magnetic source model which consists of multiple magnetic dipoles assumed to be distributed on a cylindrical surface to simulate magnetic fields around electric appliances, and calculated induced current in a simple homogeneous human model [Nishizawa, 2003, 2004a, 2004b]. Related to he characterization of the magnetic field sources, Yagitani et al studied a method of MUSIC algorithm and applied it to identification of localized field sources [Yagitani, 2004]. Tarao et al calculated the induced current due to usage of a hair dryer for a realistic human head model [Tarao, 2003]. Yamazaki et al characterized the effects of the field uniformity on maximum induced current fro homogeneous spherical human model for easy assessment of compliance with the guidelines [Yamazaki, 2005].

Yoshitomi et al measured environmental ELF magnetic filed in an apartment I Japan and proposed reduction method for the fields [Yoshitomi, 2002; Moriyama, 2005a]. They also measured ELF magnetic fields originating from equipments used for medical diagnoses and treatments. Sakurazawa et al measured personal exposure to ELF magnetic fields in working environments such as electric power substations, VDT operator, electric furnace operators, and arc welders [Sakurazawa, 2003].

Sasada reported a simple three-square-coil system to produce a uniform magnetic field in a fairly large volume inside the coil system which is advantageous over the formely proposed systems [Sasada, 2003]. Nagai et al reported exposure setups fro in vitro experiment for complex magnetic fields with static and time-varying components [Nagai, 2004].(Yamazaki)



Chiba.A., K.Isaka, K.Shoukura and T.Matsumoto [2004], gAnalysis of induced current density inside grounded and ungrounded human model exposed to electric field.h Proceedings of EMCf04 Sendai, 4C1-1, pp.809-812


Hayami.T., O.Watanabe and O.Hiwaki [2004a], gSimulation study on estimation of current sources in a nerve fiber using L1-norm method with magnetic measurement.h IEEJ Trans. EIS, Vol.124, pp.1712-1718 (In Japanese)


Hayami.T and O.Hiwaki [2004b], gA method to estimate the condition of the path of a nerve by measuring neural generation of magnetic fields.h IEEJ Trans.FM, Vol.124, pp.381-386 (In Japanese)


Hayami,T and O.Hiwaki [2004c], gSimulation study of magnetic fields produced by an active bundle of nerve fibers to estimate the distribution of fiver diameterh, Trans. Japanese Society for Medical and Biological Engineering, Vol.42, pp.261-268.


Kamimura,Y., K.Kojima and Y.Yamada [2002], gInduced current inside a spherical model of a human head due to magnetic current sources of AC drive electic shaverh. IEICE Trans.B, vol.J85-B, pp.706-714 (in Japanese).


Kamimura.Y., T.Akutsu, Y.Yamada nd K.wake [2004], gInduced current inside of the human head in the vicinity of an electric shaver.h Proceedings of EMCf04, Sendai, 4B3-2, pp.793-796


Kawahito.S., A.Cerman, K.Aramaki and Y.Tadokoro [2003], gA weak magnetic field measurement system using micro-fluxgate sensors and delta-sigma interface,h IEEE IM, pp.103-110


Kawakatsu.M., H.Ishibashi, M.Adachi, Y.Uchikawa and M.Kotani [2004], gA study on noise reduction using ICA for magnetoencephalography.h IEEJ Trans.EIS, vol.124, pp.1685-1691 (In Japanese)


Kobayashi.K., Y.Sato, D.Ando, K.Osashi, B.S.Kim and Y.Uchikawa [2004], gAnalysis of exercise-induced magnetocardiogram of normal subjects using three-dimensional magnetic measurement.h J Magnetic Society of Japan, vol.28, pp.747-751 (In Japanese)


Matsumoto.T., A.Chiba, K.Shoukura, H.Ikeda and K.Isaka [2004], gAnalysis of current density induced in an ungrounded human model by the method combining the surface-charge integral equation and the finite element method.h IEEJ Trans.PE, Vol.124, pp.778-784 (In Japanese)


Moriyama.K and K.Yoshitomi [2005a], gApartment electrical wiring: a cause of extremely low frequency magnetic field in residential areas.h Bioelectromagnetics, vol.26, pp.238-241


Moriyama,K., H.sato, K.Tanaka, Y.Nakashima, and K.Yoshitomi [2005b], gExtremely low frequency magnetic fields originating from equipment used for assisted reproduction, umbilical cord and peripheral blood stem cell transplantation, transfusion, and hemodynamicsh. Bioelectromagnetics, vol.26, pp.69-73.


Nagai.T., Y.Suzuki, T.Tanaka, M.Ikehata and M.Taki [2004], gExposure setups for in vitro experiment on biological effects of complex magnetic fields with static and time-varying components.h Asia-Pacific Radio Science Conference Proceedings, pp.422-423


Nishizawa.S and F.Landstorfer and O.Hashimoto [2003], gExperimental study on equivalent magnetic source in ELF range (in Japanese).h IEICE Trans.B, J86-B, pp.1251-1254


Nishizawa.S., H.Ruoss, F.Landstorfer and O.Hashimoto [2004a]. gNumerical study on an equivalent source model for inhomogeneous magnetic field dosimetry in the low frequency range,h IEEE on BME, Vol.51, pp.612-616


Nishizawa,S., F.Landstorfer and O.Hashimoto [2004b], gStudy of the magnetic field properties around household appliances using coil source model as prescribed by the European standard EN50366h, IEICE Trans Electron, Vol.E87-C, pp.1636-1639.


Sakurazawa.H., A.Iwasaki, T.Higashi, T.Nakayama and Y.Kusaka [2003], gAssessment of exposure to magnetic fields in occupational settings,h J Occup Health, vol.45, pp.104-110


Sasada.I [2003], gThree-coil system for producing uniform magnetic fields.h J Magnetic Society of Japan, Vol.27, pp.612-615 (In Japanese)


Tarao.H., N.Hayashi and K.Isaka [2003], gNumerical analysis of induced current in human head exposed to nonuniform magnetic field including harmonics.h IEEJ Trans.FM, Vol.123, pp.1100-1107 (In Japanese)


Yagitani.S., K.Ishibana, I.Nagao, Y.Nishi, Y.Yoshimura, H.Hayakawa and K.Tsuruda [2004], gLocalization of low-frequency electromagnetic sources.h IEICE Trans, Vol.J87-B, pp.1085-1093 (In Japanese)


Yamada.K and O.Hiwaki [2004], gEstimation of damaged area of nerve fiber by neural magnetic stimulation.h IEEJ Trans.FM, Vol.124, pp.375-380 (In Japanese)


Yamazaki.K., T.Kawamoto, H.Fujinami and T.Shigemitsu [2005], gSimplified dosimetry for human exposure to non-uniform ELF magnetic field.h IEEJ Trans FM, Vol.125,


Yoshitomi.K [2002], gMeasurement and reduction of power frequency magnetic fields in a residential areah, IEICE Trans Vol.J85-B, pp.538-546 (in Japanese).


K3.2 IF magnetic fieldi؁ARAdj

In recent years, electric appliances that utilize magnetic fields with frequency higher than the power frequency, defined as IF (intermediate frequency), for heating, detecting and switching, has raised new interest in health effects. An IH (induction heater) cooker is one of those appliances that utilize the IF magnetic field for heating ferromagnetic pans. The typical frequency of the IH cooker ranges from 20kHz to 100kHz. A similar frequency range is utilized in a metal detector usually installed at the security gates of airports, and electric article surveillance (EAS) system. Since higher frequency induces induced current inside the human body in proportion to the frequency, stricter magnetic field levels are set for the higher frequency range in some existing exposure guidelines.

Kamata et al. characterized the magnetic fields generated by induction cooking by a series of measurement [Kamata, 2004]. Yamazaki et al. proposed a simple method to characterize the magnetic field distribution around appliances in the IF range by identifying equivalent magnetic dipole moments [Yamazaki, 2004a, 2004b]. Suzuki et al. conducted numerical calculation of induced currents inside an anatomically correct human model when exposed to IF magnetic field [Suzuki, 2004a, 2004b, 2005] (Suzuki and Yamazaki).



Kamata.K and A.Haga [2004], gMeasurement of magnetic fields produced by induction cooking heaters.h Proceedings of EMCf04 Sendai, 4D2-2, pp.869-872


Kamimura.Y., K.Komori, M.Shoji, Y.Yamada, S.Watanabe and Y.Yamanaka [2004], gHuman body impedance for contact current measurement in Japan.h Proceedings of EMCf04 Sendai, 3B4-1, pp.585-588


Suzuki.Y., K.Wake, S.Watanabe, M.Taki, S.Watanabe and Y.Yamanaka [2004a], gNumerical calculation of induced current densities in the human body due to intermediate frequency magnetic fields.h Proceedings of EMCf04, Sendai, 4B3-4, pp.801-804


Suzuki.Y., K.Wake, S.Watanabe, M.Taki, S.Watanabe and Y.Yamanaka [2004b], gNumerical dosimetry for induced current densities within Japanese adult male and female voxel models due to magnetic field from induction heat hob.h Asia-Pacific Radio Science Conference Proceedings, pp.420-421


Suzuki,Y and M.Taki [2005], g h IEEJ Trans FM, Vol.125-A, pp.427-433.



Takeda.M., Y.Bannno, H.Hirata, Y.Okita, M.Kimura and T.Sugiura [2004], gElectromagnetic field stimulation around implantable cardiac pacemakers caused by EAS system.h Asia-Pacific Radio Science Conference Proceedings, pp.444-446


Yamazaki.K., T.Kawamoto, H.Fujinami and T.Shigemitsu [2004a], gEquivalent dipole moment method to characterize magnetic fields generated by electric appliance: extension to intermediate frequencies of up to 100kHz.h. IEEE EMC 46, pp.115-120


Yamazaki.K., T.Kawamoto, H.Fujinami and T.Shigemitsu [2004b], gEquivalent dipole estimation for characterization of magnetic fields and induced currents near household appliance eELF to 100kHz).h Proceedings of EMCf04, Sendai, 4B3-1, pp.789-792



K3.3 RF and MWiA؁AnӁj

 There has been increasing concern about adverse health effect in RF and microwave frequency range due to proliferation of mobile phones. In order to investigate this problem, computational and experimental works haven been conducted. Recent trends in Japan are summarized as follows:

1) Measurement techniques for electric constants of lossy dielectric

  For reliable dosimetry, it is essential to measure electrical constants of human tissue and then to develop material for phantom [Fukunaga, 2004]. Additionally, uncertainties of an electric probe have been evaluated [Watanabe,2004b]. 

2) Development of experimental setups for small animals and in-vitro study

 Some new techniques using ferrite material or high permittivity materials to realize a highly localized exposure in small animals has been developed [Wang, 2003b, 2004c], and detailed analysis for various uncertainties in exposure setups has been conducted [wang, 2002b, 2004b].

3) Dosimetry for child

Based on the report by the NRPB, it is concerned that children might be more vulnerable to any adverse effects of RF radiation than adults. In order to give some insight on this problem, dosimetry has been conducted using a realistic child head model [Fujiwara, 2003, 2004]. A scaling technique for producing a realistic child model has been developed and adopted widely in the world [Wang, 2003a]. A parallel FDTD technique based on PCs has also been developed for large-scale dosimetry of mobile phones [Wang, 2004a].

4) Temperature rise due to RF exposures

 Peak-spatial averaged SAR is used as a measure in the ICNIRP guideline to evaluate the safety of humans for RF electromagnetic field exposure, while temperature increase would be a direct cause of physical burning and physiological effect. In order to bridge this gap, a correlation between peak SAR and temperature increase has been investigated [Fujimoto, 2003a, 2003b, 2004a, 2004c; Hirata, 2002, 2003a, 2003b, 2004a, 2004b] (Fujiwara).



Fujimoto.M., A.Hirata and T.Shiozawa [2003a]. gTemperature increase in the heads of adult and children due to dipole antenna.h Proc of IEEE AP-S International Symposium


Fujimoto.M., A.Hirata,, O.Fujiwara and T.Shiozawa [2003b], gComparison of maximum temperature increase in the head models of children and adult due to dipole antenna.h Proc of IEEE Topical Conf.on Wireless Communication Technology, 14-2.


Fujimoto.M., A.Hirata and T.Shiozawa [2004a], gCorrelation between temperature increase and SAR in the child head due to dipole antenna.h IEICE Trans B, vol.J87-B, pp.320-322.


Fujimoto.M., A.Hirata, J.Wang, O.Fujiwara and T.Shiozawa [2004b], gCorrelation of maximum temperature increase and peal SAR in the child and adult head models due to dipole antenna.h Proceedings of EMCf04 Sendai, 3B5-2, pp.601-604


Fujimoto.M., A.Hirata, J.Wang, O.Fujiwara and T.Shiozawa [2004], gTime constant of temperature increase in the human head models due to dipole antenna at microwave frequencies.h Asia-Pacific Radio Science Conferencde Proceedings, 525p.


Fujino.T., A.Hirata and T.Shiozawa [2003], gEvaluation of induced SAR in the human body due to EM waves emitted from a dipole antenna at 400MHz band,h Proc of IEEE Topical Conf. on Wireless Communication Technology, 14-1.


Fujiwara.O., J.Wang, T.,Hisada, S.Watanabe and Y.Yamanaka [2003], gComparison of local SAR in realistic head models of adult and children for portable telephones.h IEICE Trans. Vol.J86-B, pp.1219-1224 (In Japanese)


Fujiwara.O., K.Miyamoto and J.Wang [2004], gThermal index evaluation of local SAR in MRI-based head models of adult and children for portable telephones.h IEEJ Trans.EIS, vol.124, pp.2427-2432.


Fukunaga.K., S.Watanabe and Y.Yamanaka [2004], gDielectric properties of tissue-equivalent liquids and their effects on specific absorption rate,h IEEE EMC, vol.46, pp.126-129


Hanada.E and T.Kudou [2004], gMedical electronic equipment safety in hospital environments with@wireless communication systems.h Proceedings of EMCf04 Sendai, 2B4-2, pp.345-348


Hanazawa.M., R.Kumahara, S.Mochizuki, K.Wake, S.Watanabe, M.Taki, Y.Kamimura, Y.Yamanaka and H.Shirai [2004], gDevelopment of a millimeter-wave exposure setup for rabbit eye.h Asia-Pacific Radio Science Conference Proceedings, pp.457-458


Hikage.T., T.Nojima, S.Watanabe and T.Shinozuka [2004], gA study on implantable cardiac pace maker EMI from cellular radios in semi-echoic environments.h Proceedings of EMCf04 Sendai, 3B2-2, pp.565-568


Hirata.A., H.Watanabe and T.Shiozawa [2002], gSAR and temperature rise in the human eye induced by obliquely incident plane waves.h IEEE EMC, vol.44, pp.594-596.


Hirata.A., M.Morita and T.Shiozawa [2003], gTemperature increase in the human head due to a dipole antenna at microwave frequencies,h IEEE EMC, pp.109-116


Hirata.A and T.Shiozawa [2003], gCorrelation of maximum temperature increase and peak SAR in the human head due to handset antennas.h IEEE MTT, vol.51, pp.1834-1841.


Hirata.A., T,Fujino and T.Shiozawa [2003]:, g SAR in the human body due to EM waves emitted from a dipole antenna at 400MHz band.h Proc of IEEE Internaitonal Symposium on EMC, Jun 2003.


Hirata.A., T.Fujino and T.Shiozawa [2004], gSAR and temperature increase induced in the human body due to body-mounted antenna.h Proc of IEEE AP-S International Symposium.


Hirata.A., T,Fujino, M.Fujimoto and T.Shiozawa [2004], gCorrelation of SAR and temperature increase induced in the human body due to body-mounted antennas at 400MHz and 900MHz.h Proc of International Symposium on Antenna and Propagat., pp.785-788.


Iyama.Y., H.Ebara, Y.Tarusawa, S.Uebayashi, M.Sekijima and T.Nojima [2004], gLarge scale in vitro experiment system for 2GHz exposure.h Bioelectromagnetics, vol.25, pp.599-606


Kita.M., A.Hirata and T.Shiozawa [2002], gTemperature rises in the human eye exposed to EM waves emitted fron a dipole antenna at various microwave frequencies.h IEICE Trans.B, vol.J85-B, pp.132-139.

Koyanagi.Y., H.Kawai, K.Ogawa and K.Ito [2003], gEstimation of the local SAR in the human abdomen using a human body phantom and small antennas at 150MHz.h IEICE Trans.B, Vol.J86-B, pp.1207-1218 (In Japanese)


Morita.M., A.Hirata and T.Shiozawa [2002], gPrediction of temperature rise in the human head in terms of localSAR.h IEICE Trans.B, vol.J85-B, pp.723-725.


Nagaoka.T., S.Watanabe, K.Sakurai, E.Kunieda, S.Watanabe and M.Taki [2004], gDevelopment of realistic high-resolution whole-body voxel models of Japanese adult male and females of average height and weight, and application of models to radio-frequency electromagnetic-field dosimetry,h Phys Med Biol, vol.49, pp.1-15


Nakamatsu.S., R.Yamaguchi and S.Uebayashi [2004], gLoop antenna for localized exposure of small animals.h Asia-Pacific Radio Science Conference Proceedings, pp.442-443


Ohshima.T., and O.Fujiwara [2002], gDependence on human body modeling of electromagnetic interference of cardiac pacemaker by portable telephones.h Trans.B, IEICE, vol.J85-B, pp.726-728.


Ohshima.T., E.Takahashi, J.Wang and O.Fujiawra [2002], g Verification of electromagnetic interference testing of cardiac pacemakers by portable terminals with an MRI-based anatomical human model.h Trans.B, IEICE, vol.J85-B, pp.2419-2421.


Ohtake.Y and S.Kuwano [2004], gFDTD analysis of induced currents in a realistic heterogeneous model of man exposed to RF plane wave.h IEICE Trans. B, J87-B, pp.1116-1118 (In Japanese).


Tokunaga.R., Y.Suzuki, T.Tanaka and M.Taki [2004], gThermal field analysis for in vitro exposure apparatus in rectangular waveguide with transversal slits.h Proceedings of EMCf04 Sendai, 3B4-2, pp.589-592


Toyoshima.T [2004], gElectromagnetic interference in implantable cardiac pacemaker and cardioverter defibrillator.h Proceedings of EMCf04 Sendai, 2B4-3, pp.349-352


Wang.J., O.Fujiwara and T.Nojima [2002], gDependence on use position of localized electromagnetic absorption in human head for 2GHz portable telephones.h Trans.B, IEICE, vol.J85-B, pp.649-655.


Wang.J., O.Fujiwara and T.Ono [2002], gDosimetry evaluation of a whole body exposure setup for small animal at 2.45GHz.h IEICE Trans. Commin, vol.E85-B, pp.2963-2965.


Wang.J and O.Fujiwara [2003a], gComparison and evaluation of electromagnetic absorption characteristics in realistic human head models of adult and children for 900-MHz mobile telephones.h IEEE MTT, vol.51, pp.966-971


Wang.J and O.Fujiwara [2003b], gRealizing highly localized exposure in small animals with absorbing material covered holder to test biological effects of 1.5GHz cellular telephones.h IEICE Trans.Commun, pp.1660-1665.


Wang.J., O.Fujiwara, S.Watanabe and Y.Yamanaka [2004a], gComparison with a parallel FDTD system of human-body effect on electromagnetic absorption for potable telephones.h IEICE Trans MTT, vol.52, pp.53-57.


Wang.J., T.Saito and O.Fujiwara [2004b], gUncertainty evaluation of dosimetry due to plastic holder for restraining small animal in In Vivo near field exposure setup,h IEEE EMC, vol.46, pp.263-267


Wang.J and O.Fujiwara [2004c], gA new method for realizing local exposure to young rat heads using electric flux concentration for bioeffect test of mobile telephones.h Proceedings of EMCf04 Sendai, 3B3-3, pp.581-584

Watanabe.S., N.Hirose, T.Nagaoka, N.Hatakenaka, Y.Tanaka, M.Takahashi, Y.Suzuki, M.Taki,, O.Fujiwara and Y.Yamanaka [2004a], gDevelopment of smart voxel models of whole human-bodies for numerical dosimetry.h Proceedings of EMCf04, Sendai, 4B3-3, pp.797-800


Watanabe.S., Y.Miyota, M.Takabe, H.Asou, Y.Ishi, K.Satoh, K.Fukunaga, A.Syzuki, T.Sugiyama, I.Nishiyama, T.Shinozuka and Y.Yamanaka [2004b], gUncertainties of SAR-probe calibration and of SAR measurement for compliance tests of cellular phones.h Proceedings of EMC04 Sendai, 3B1-3, pp.557-560


K4 Biomedical Applications


K4.1 Thermal Therapy (ɓ)

In recent years, various types of medical applications of microwaves have been investigated. Among them, minimally invasive microwave thermal therapies are of great interest. They are interstitial hyperthermia and microwave coagulation therapy for thermal treatment of cancer, cardiac catheter ablation for ventricular arrhythmia treatment, etc. Previously, a coaxial-slot antenna, which is one of the thin antennas for interstitial heating, has been studied. In this research, the heating characteristics of the antenna are investigated by numerical simulation based on FDTD calculations [Saito, 2003] and phantom experiments. Moreover, the results of hyperthermic treatments for neck tumor by use of the coaxial-slot antenna and the array applicator composed of several coaxial-slot antennas are reported [Saito, 2004a]. In addition, the improvement of the characteristics of the coaxial-slot antenna especially the input impedance of the antenna is considered [Saito, 2004b] and the feeding technique of the array applicator composed of several antennas is investigated [Saito, 2004c] [Ito].



Saito.K., H. Yoshimura, and K. Ito [2003], gNumerical simulation for interstitial heating of actual neck tumor based on MRI tomograms by using a coaxial-slot antenna.h IEICE Transactions on Electronics, vol. E86-C, pp.2482-2487 (In Japanese)

Saito.K., H.Yoshimura, K.Ito, Y.Aoyagi and H.Horita [2004a], gClinical trials of interstitial microwave hyperthermia by use of coaxial-slot antenna with two slots.h IEEE Transactions on Microwave Theory and Techniques vol.52, no.8, pp.1987-1991.


Saito.K., K. Miyata, H. Yoshimura, and K. Ito [2004b], gTreatment system of interstitial microwave hyperthermia: clinical trials for neck tumor and improvement of antenna elements,h Digest of International Union of Radio Science (URSI) National Radio Scientific Meeting (Monterey, USA), p. 195, June


Saito.K., H.Yoshimura and K.Ito [2004c], gStudy on feeding technique of array applicator for uniform heating of large-volumed tumor in interstitial microwave heating.h IEICE Trans. B, Vol.J87-B, pp.410-420 (In Japanese)


K4.2 Microwave Imaging of the Human Body ({)

Chirp Pulse Microwave Computed Tomography is a noninvasive imaging modality which enables microwave imaging of a human body using a chirp pulse microwave signal and signal processing techniques. The prototype model using a microwave from 1 to 2 GHz showed that the spatial resolution is better than 10 mm and temperature variation less than 0.3 degree Celsius can be measurable. The higher resolution model which works at 2 to 3 GHz has also been developed for diagnostic imaging of an early stage breast tumor. Feasibility of the practical application of CP-MCT has been investigated through a series of computational studies and basic studies using those two models. A new CP-MCT with fan beam geometry which is able to collect projection data very quickly is now being developed for a high speed imaging of experimental animals [Miyakawa].




Bertero.M., F. Conte, M. Miyakawa and M. Piana [2001], gComputation of the response function in Chirp-Pulse Microwave Computerized Tomography,h Inverse Problems, vol.17, pp.485-500


Bertero.M., P. Boccacci, F. Conte, M. Miyakawa and M. Piana [2002], gA linear model for CP-MCT,h Proc. PIERS 2002 in Cambridge, July 1-5, p.591


Miyakawa.M., Y. Kawada and M. Bertero [2001a], gImage generation of chirp pulse microwave computed tomography (CP-MCT) by numerical computation –Computation of the human head model-,h Trans. IEICE Japan, J84-D-II, pp.1512-1521


Miyakawa.M., M. Eiyama, and N. Ishii [2001b], gAn attempt of time-domain microwave computed tomography for biomedical use,h Proc. IEEE EMB International Symposium.


Miyakawa.M., K. Orikasa, M. Bertero, P. Boccacci, F. Conte and M. Piana [2002a], gExperimental validation of a linear model for data reduction in Chirp-Pulse Microwave CT,h IEEE Trans. Medical Imaging, vol.27, pp.385-395


Miyakawa.M., K. Orikasa, and M. Bertero [2002b], gEvaluation of the response function and its space dependence in Chirp Pulse Microwave Computed Tomography (Co-MCT),h IEICE, Trans. Inf. & Syst., Vol. E85-D, pp.52-59


Miyakawa.M., Wu Jing, K. Sugawara and M. Bertero [2002c], gFDTD-based computation to find an optimal configuration of the printed array antenna used for a fan beam scanner of chirp pulse microwave computed tomography (CP-MCT),h Proc. PIERS 2002 in Cambridge, July 1-5, p.592


Miyakawa.M., K. Sugawara, M. Bertero and M. Piana [2002d], gComputational Imaging of the Breast- and Head-Models in CP-MCT,h Proc. PIERS 2002 in Cambridge, July 1-5, p.593


Miyakawa.M., E. Harada, N. Ishii, and M. Bertero [2002e], gDevelopment of a printed dipole array antenna for fan beam-type chirp-pulse microwave computed tomography (CP-MCT),h Proc. PIERS 2002 in Cambridge, July 1-5, p.871


Miyakawa.M., E. Harada and Wu Jing [2003], gChirp pulse microwave computed tomography(CP-MCT) equipped with a fan beam scanner for high-speed imaging of a biological target,h Proc. 25th Annual International Conference on Engineering in Medicine and Biology Society, pp.1031-1034


K4.3 Thermal therapy- Inductive heating ()

A novel implant with the function of a high efficient temperature raise is proposed to achieve a local high temperature hyperthermia or ablation therapy. The idea of the new implant with a heating function is based on not material component but on resonant circuit theory viewpoint 1) .The new implant proposed here consists of a small coil and a microchip condenser to make a resonant circuit. By applying an RF magnetic field to the implant, large current flows in the coil based on the resonance and elevate the coil temperature efficiently. As a coil, a silver wire or a stainless is used. The temperature rise of more than 70 from the initial value is obtained at 15 cm depth of agar phantom in a case of implant with the diameter of 3 mm and the length of 4 mm, using a ferrite core applicator with output power of 500 W at the resonant frequency of 4 MHz. This idea of the implant can be applied to a stent with a heating function [Kotsuka].



Kotsuka.Y and H.Okada [2003], gDevelopment of Small and High Efficiency Implant for Deep Local Hyperthermia,h Jap. J. of Hyperthermic Oncology, vol.19, pp.11-22


K4.4 Radiometry (Y)

Multi-frequency microwave radiometer system for noninvasive temperature measurement of biological tissues has been at the final stage of its development as well as the temperature retrieval method from measured brightness temperatures of biological tissues. Chirp radar-type microwave computed tomography which can provide a cross sectional image of temperature change has been also under development [Sugiura].



Hand.J.W., G.M.J.Van Leeuven, S.Mizushina, J.B.Van de Kamer, K.Maruyama, T.Sugiura, D.V.Azzopardi and A.D.Edwards [2001], gMonitoring of deep brain temperature in infants using multi-frequency microwave radiometry and thermal modelling,h Phys. Med. Biol, vol.46, pp.1885–1903


Harada.E., J.Wu and M.Miyakawa [2002], gExperimental determination of the optimal arrangement of a receiving antenna consisted of dipole antennas for microwave imaging,h Rep. of IEICE, MBE2002 73-84, pp.29-32


Kouno.Y., A.Hashizume, S.Hoshino, H.Hirata, Y.Okita and T.Sugiura [2004], gDevelopment state of multifrequency microwave radiometer system for noninvasive measurement of infantfs deep brain temperatures.h Asia-Pacific Radio Science Conference Proceedings, pp.438-441


Miyakawa.M [2002], gExperimental validation of a linear model for data reduction in chirp-pulse microwave CT,h IEEE Trans. Med. Imaging, pp.385-395


Sugiura.T., G.Mukumoto, H.Hirata, K.Ohashi, Y.Okita, S.Mizushina, G.M.J.Van Leeuwen and J.W.Hand [2002a], gDevelopment of a five-band microwave radiometer system for non-invasive measurement of deep brain temperature in new-born babies,h Proceedings of 2002 Asia-Pacific Microwave Conference, pp.914-917


Sugiura.T., H.Hirata, K.Ohashi, Y.Okita, S.Mizushina, G.M.J.Van Leeuwen and J.W.Hand [2002b], gA study of the influence of tissue conductivity for microwave radiometric weighting functions in non-invasive measurement of babyfs brain temperature,h Proceedings of 2002 Asia-Pacific Microwave Conference, pp.1091-1094


Sugiura.T., Y.Kouno, A.Hashizume, H.Hitara, J.W.Hand, Y.Okita and S.Mizhusina [2004], gFive band microwave radiometer system for non-invasive measurement of brain temperature in new-born infants: system calibration and its feasibilityh Proceedings of 2004 Annual Conference of IEEE EMBS, pp.2292-2295


Yonemura.Y., N.Ishi and M.Miyakawa [2003], gAn Absolute Gain Measurement of Printed Dipoles for Microwave CT,h Rep. of IEICE, AP2003 145-179, pp.117-122


 K4.5 Soft heatingi؁j

In hypertnemia, the soft-heating method has been proposed. This is an inductive heating method that uses as a hear element a thermosensitive magnetic material. The feature of this method is automatic temperature control using Curie-point of the magnetic material. When the element is implanted into the tumor tissue, however, authors have to adjust the size of element to that of each tumor tissue. Therefore, the purpose of this study is to clarify heat characteristics of heat elements with various volumes.

The heat element is composed of a thermosensitive magnetic material and a metal ring. The thermosensitive magnetic material used to experiment is Ni-Cu-Zn ferrite and Curie-point is 90. Moreover, the copper ring is wrapped around the ferrite. The aim of wrapping copper ring is increase of the heat quantity generated compared with that using only the magnetic material. When temperature of the thrmosensitive magnetic material is lower than the Curie-point, the magnetic flux is concentrated by the effect of high permeability of the magnetic material. Then, short-circuit current induced in the copper ring, raises the temperature of heat element. In experiments, this element is put in the heat insulator, then excited by solenoidal coil. The specification of this coil is 8mT at 100 kHz.

The results provided evidence that the temperature characteristics show a saturation tendency with an increase of the element volume. Based on this tendency, it seems reasonable to suggest that sufficient heating can be obtained, even on smaller element volumes. Therefore, when considering heating per unit volume, it is expected that a volume with the most effective heating temperature can be obtained. For further research, we will continue to analyze the temperature characteristics, aiming to achieve the high hyperthermia [Matsuki].



Deger.S., D.Boehmer, I.Toerk, J.Roigas, V.Budach and S.A.Loening [2002], gInterstitial Hyperthermia using Self-Regulating Thermoseeds Combined with Conformal Radiation Therapy,h European Urology, vol.42, pp.147-153


Sato.F., M.Jojo, H.Matsuki, T.Sato, M.Sendoh, K.,Ishiyama and K.I.Arai [2002], gThe Operation of Magnetic Micromachine for Hyperthermia and Its Exothermic Characteristics,h IEEE Trans. Magn, vol.38, pp.3362-3364

K4.6 current distribution MRIiA֖j

Magnetic resonance imaging of electrical phenomena in living bodies is potentially useful for quantitative evaluations of biological effects of electromagnetic fields, and for direct detection of neuronal electrical activities in the brain. Magnetic field in an object causes a shift in the resonant frequency [Sekino, 2004a]. Stationary electric current causes an increase in the apparent diffusion coefficient [Yamaguchi, 2003]. Spatial distributions of externally applied magnetic field and electrical current can be estimated from these changes in magnetic resonance signals. These methods have potential medical applications such as imaging of current distributions in electrical defibrillation. Detection of electrical currents associated with neuronal or muscular electrical activities requires extremely high sensitivity. The sensitivity for detecting weak magnetic fields was estimated using numerical simulations [Hatada, 2005a, 2005b] and experiments [Hatada, 2005c]. The theoretical limit of sensitivity was approximately 10-8 T. These studies potentially lead to a new method for visualizing brain function with a spatial resolution of millimeters and a temporal resolution of milliseconds. The ADC reflects electrical conductivity of a tissue, which enables an estimation of anisotropic conductivity of the tissue [Sekino, 2003a, 2004b, 2004c]. This method was applied to imaging of electrical conductivity in the human brain. Several regions in the white matter such as the corpus callosum and the internal capsule exhibited high anisotropy in conductivity. Magnitude and phase of magnetic resonance signals are affected by permittivity [Sekino, 2005; Mihara, 2005]. A distinctive signal inhomogeneity arises in images of objects whose dimension is comparable to the wavelength of electromagnetic fields at the resonant frequency. This phenomenon, dielectric resonance, particularly appears in scanners with high static fields. Electric current in electrolyte solution give rise to fluid motion. Magnetic resonance imaging was applied to visualization of the flow velocity [Sekino, 2003b, 2003c, 2004d]. In strong static magnetic field, biological macromolecules such as fibrin and collagen are oriented in the direction parallel or perpendicular to the magnetic field. The magnetic orientation causes a change in the spin-spin relaxation time of gels, which contain these macromolecules [Takeuchi, 2003, 2004a, 2004b, 2005].



Fukami.T., T.Shimada, T.Akatsuka and Y.Saito [2004], gThe analysis for activation in the brain during hearing the amplitude-modulated tone by fMRI measurement.h IEEJ Trans EIS, vol.124 , pp.1692-1697 (In Japanese)


Hatada. T., M. Sekino and S. Ueno [2005a], gFinite element method-based calculation of the theoretical limit of sensitivity for detecting weak magnetic fields in the human brain using magnetic-resonance imaging.h Journal of Applied Physics, vol. 97, pp. 10E109


Hatada.T., M.Sekino and S.Ueno [2005b], gFEM based brain RF electromagnetic field distribution in magnetic resonance imaging.h Journal of the Magnetics Society of Japan, vol.29, pp.364-367 (In Japanese)


Hatada. T., M. Sekino and S. Ueno [2005c], gDetection of weak magnetic fields induced by electrical currents with MRI: Theoretical and practical limits of sensitivity.h Magnetic Resonance in Medical Sciences, vol. 3, pp. 159-163


Kawase.K., Y.Watanabe, Y.Ogawa and H.Ito [2004], gComponent spatial pattern analysis of chemicals using Terahertz spectroscopic imaging.h IEEJ Trans.EIS, vol.124, pp.1339-1344 (In Japanese)


Mihara H., N. Iriguchi and S. Ueno [2005], gImaging of the dielectric resonance effect in high field magnetic resonance imaging.h Journal of Applied Physics, vol. 97, pp. 10R305


Sekino. M., K. Yamaguchi, N. Iriguchi and S. Ueno [2003a], gConductivity tensor imaging of the rat brain using diffusion-weighted magnetic resonance imaging.h Journal of Applied Physics, vol. 93, pp. 6730-6732


Sekino. M., K. Yamaguchi, N. Iriguchi and S. Ueno [2003b], gMagnetic resonance imaging of fluid motion associated with electrodeposition processes.h IEEE Transactions on Magnetics, vol. 39, pp. 3393-3395


Sekino. M., K. Yamaguchi, N. Iriguchi and S. Ueno [2003c], gMagnetic resonance imaging of convection in an electrolyte solution and extracellular fluid associated with stationary electric currents.h Journal of Applied Physics, vol. 94, pp. 5359-5366


Sekino. M., T. Matsumoto, K. Yamaguchi, N. Iriguchi and S. Ueno [2004a], gA method for NMR imaging of a magnetic field generated by electric current.h IEEE Transactions on Magnetics, vol. 40, pp. 2188-2190


Sekino. M., Y. Inoue and S. Ueno [2004b], gMagnetic resonance imaging of mean values and anisotropy of electrical conductivity in the human brain.h Neurology and Clinical Neurophysiology, vol. 55, pp. 1-5


Sekino. M., K. Yamaguchi, N. Iriguchi and S. Ueno [2004c], gConductivity imaging of the brain using diffusion tensor magnetic resonance imaging.h Journal of the Magnetics Society of Japan, vol. 28, pp. 649-656 (In Japanese)


Sekino.M., K.Yamaguchi, N.Iriguchi and S.Ueno [2004d], gMeasurement of convection using magnetic resonance imaging.h Journal of the Magnetics Society of Japan, vol.28, pp.722-726 (In Japanese)


Sekino. M., H. Mihara, N. Iriguchi and S. Ueno [2005], gDielectric resonance in magnetic resonance imaging: Signal inhomogeneities in samples of high permittivity.h Journal of Applied Physics, vol. 97, pp. 10R303


Takeuchi. M., M. Sekino, K. Yamaguchi, N. Iriguchi and S. Ueno [2003], gMulticomponent proton spin-spin relaxation of fibrin gels with magnetically oriented and randomly oriented fibrin fiber structures.h Journal of Applied Physics, vol. 93, pp. 6736-6738


Takeuchi. M., M. Sekino, N. Iriguchi and S. Ueno [2004a], gSpin-spin relaxation and apparent diffusion coefficient of magnetically oriented collagen gels.h IEEE Transactions on Magnetics, vol. 40, pp. 2976-2978


Takeuchi. M., M. Sekino, K. Yamaguchi, N. Iriguchi and S. Ueno [2004b] gT2 relaxation of water molecules surrounding magnetically oriented fibrin gels.h Journal of the Magnetics Society of Japan, vol. 28, pp. 468-471 (In Japanese)


Takeuchi. M., M. Sekino, N. Iriguchi and S. Ueno [2005], gDependence of the spin-spin relaxation time of water in collagen gels on collagen fiber directions.h Magnetic Resonance in Medical Sciences, vol. 3, pp. 153-157


Yamaguchi.K., M.Sekino and S.Ueno [2003], gCurrent distribution image of the brain using diffusion-weighted magnetic resonance imaging,h Journal of Applied Physics, vol.93, pp.6739-6741