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The Mammalian Brain in the Electromagnetic Fields Designed by
Man-with Special Reference to Blood-Brain Barrier Function,
Neuronal Damage and Possible Physical Mechanisms
Leif G. Salford,1,∗)Henrietta Nittby,1Arne Brun,2Gustav Grafstr¨
om,3
Lars Malmgren,4Marianne Sommarin,5Jacob Eberhardt,3Bengt Widegren6
and Bertil R. R. Persson3
1Department of Neurosurgery, Lund University, Sweden
2Neuropathology, Lund University, Sweden
3Medical Radiation Physics, Lund University, Sweden
4Applied Electronics, Lund University, Sweden
5Department of Plant Biochemistry, Lund University, Sweden
6Tumour Immunology, Lund University, Sweden
∗)Corresponding author. E-mail: Leif.Salford@med.lu.se
2L. G. Salford et al.
Life on earth was formed during billions of years, exposed to, and shaped by the original
physical forces such as gravitation, cosmic irradiation, atmospheric electric fields and the
terrestrial magnetism. The Schumann resonances at 7.4 Hz are an example of oscillations
possibly important for life.1)
The existing organisms are created to function in harmony with these forces. However,
in the late 19th century mankind introduced the use of electricity, in the early 20th century
long-wave radio and in the 1940-ies short-wave radio. High frequency RF was introduced in
the 50-ies as FM and television and during the very last decades, microwaves of the modern
communication society spread around the world. Today, however, one third of the world’s
population is owner of the microwave-producing mobile phones and an even larger number
is exposed to the cordless RF emitting systems. To what extent are all living organisms
affected by these, almost everywhere present radio frequency fields? And what will be the
effects of many years of continuing exposure?
Since 1988 our group has studied the effects upon the mammalian blood-brain barrier
(BBB) in rats by non-thermal radio frequency electromagnetic fields (RF-EMF). These have
been shown to cause significantly increased leakage of the rats’ own blood albumin through
the BBB of exposed rats, at energy levels of 1W/kg and below, as compared to non-exposed
animals in a total series of about two thousand animals.2)−6) One remarkable observation
is the fact that the lowest energy levels, with whole-body average power densities below
10mW/kg, give rise to the most pronounced albumin leakage. If mobile communication,
even at extremely low energy levels, causes the users’ own albumin to leak out through the
BBB, also other unwanted and toxic molecules in the blood, may leak into the brain tissue
and concentrate in and damage the neurons and glial cells of the brain.
In later studies we have shown that a 2-h exposure to GSM 915 MHz, at non-thermal
SAR-values of 0.2, 2 and 200 mW/kg, gives rise to significant neuronal damage, seen not
only 50 days after the exposure7) but also after 28 days but not after 14 days. Albumin
extravasations and uptake into neurons was enhanced after 14 days, but not after 28.8)
In our continued research, also the non-thermal effects on tissue structure and memory
function of long-term exposure for 13 months are studied.9) We have also performed micro-
array analysis of brains from rats exposed to short term GSM both at 1,800 MHz and at
900MHz and have found significant effects upon gene expression of membrane associated
genes as compared to control animals.10),11)
Most of our findings support that living organisms are affected by the non-thermal radio
frequency fields. Some other studies agree while others find no effects.
The mechanisms by which the EMFs may alter BBB permeability are not well under-
stood. At low field strengths, the effects on body temperature are negligible and thus heating
effects are not involved. A change in the physicochemical characteristics of membranes has
been suggested as a cause.12)
We have performed experiments to verify a quantum mechanical model for interaction
with protein-bound ions. Our results show that controlled frequency and amplitude of ELF
EM fields upon spinach plasma vesicles can steer transport over the membrane.13) This
may be a first proof of a resonance phenomenon where appropriate levels of frequency and
amplitude in the right combination have the potency to communicate with the biology of
membranes and transport systems. Our study has prompted us to elaborate on magnetic
resonance models; the Ion Cyclotron Resonance (ICR) model and the Ion Parametric Reso-
nance (IPR) Model in an attempt to explain the occurrence of resonance frequencies. This
is extensively described here under the heading: Mechanisms behind the effects of electro-
magnetical fields upon biology.
We also bring forward the concept of solitons being active in membranes and DNA/RNA-
transcription as a possible mean to understand and prove the biological effects of EMF.
The Nishinomiya-Yukawa International and Interdisciplinary Symposium 2007 raised the
question: What is Life? An obvious and simple answer could be: It is DNA!
The DNA strand can be looked upon as an antenna resonating in the microwave band
6GHz with its harmonics and subharmonics.14)−18) If this holds true, the dramatic situa-
tion might exist, that all living organisms have a receptor for the newly constructed and
world-wide man-made microwaves, leading to a direct effect upon the function of DNA - in
concordance with our experimental findings!
Our generation invented the microwave emitters. We now have an imperative obliga-
tion to further investigate the links between EMF and biology in order to prevent possible
detrimental effects of the microwaves.
Progress of Theoretical Physics Supplement No. 173, 2008 3
Fig. 1. Time-line for the origin of life (for a more detailed time tree, see Williams 2007).
§1. Introduction
Our Universe was born in the “Big Bang” approximately 15 billion years ago,
our sun and most of the stars were formed 10 billion years later.
Four and a half billion years ago our Earth was formed and already 1.5 billion
years after this, the earliest unicellular life/bacteria/cyanobacteria started life on
Earth.
Two and a half billion years ago the first photosynthesis by blue-green algae
took place and 1 billion years ago the first nucleated cells with organelles emerged.
This was followed 500 million years ago by the creation of the first vertebrates and
they finally lead to the development of mammals and then, 2 million years ago, the
emergence of our own species, Homo.
Since its origin, life on Earth has been exposed to, and shaped by, the original
physical forces such as gravitation, cosmic irradiation, atmospheric electric fields and
the terrestrial magnetism.
Life has also developed in a multitude of cyclic events occurring with different
intervals: Earth’s own rotation (1 day), Earth’s revolution around the sun (1 year),
4L. G. Salford et al.
Earth’s
radius
4600 km
D-region
80-90 km
F-region
E-region
Li gh t ni ng b e tw e en
th e D- re g io n a nd E a rt h ge n e ra te th e S ch u m a n n re s o n an c e s
at 7 ,4 H z (a n d 14 , 2 0, 2 6, 33 H z) t he se o sc illa ti on s u nd er
th e D- re g io n ar e po ss ib l y im po r ta nt fo r life an d co r re s po n d di re c tly
to th e br ai n ’s EE G a lp h a w a ve s 8 -1 3 ,9 H z
(r el ax a ti on ) an d be t a wa v es 1 4- 3 0 Hz (c o n ce n tr at io n )
Microwaves
X-ray
Ultraviolet
light
Visible and
infrared
light
Fig. 2. Ionosphere and Schumann resonances.
the sun’s rotation around its own axis (27 days), the synodic period of the moon
(29.5 days) and further, the magnetic storms generated by the solar flare generating
solar winds with plasma flows which appear 10 times in a month and vary with an
eleven year periodicity. These magnetic storms produce alterations of the Earth’s
geomagnetic field (GMF) lasting from hours to days all around the Earth. The GMF
forms an extremely important shield around the Earth, the magnetosphere with its
magnetosheath, preventing the solar wind to reach Earth’s surface at a harmful level.
The protective effect of the magnetosheath can be seen as the solar wind approaches
the magnetosphere, where it drops abruptly. A shock wave, known as a bow shock,
develops, reminding of the waves in front of a ship travelling through the water, and
thus the solar wind deflects around the magnetosphere.
Earth is surrounded by its thin atmosphere reaching only about 180 km above
its surface. In parallel with this exists the 3-layered ionosphere (Fig. 2), with its
innermost D-region surrounding Earth 80-90 km above its surface. Between 100 and
150 km is the E-region and between 150 and 180 km the F-region. The existence
of the ionosphere is an absolute prerequisite for the development and persistence of
life.
The enhanced X-rays from solar flares, extreme ultraviolet and all other forms of
ultraviolet light are prevented from reaching Earth by the ionosphere whilst visible
light and infrared rays pass it.
Ionized particles (mainly protons and electrons) and the enhanced X-rays from
solar flares are prevented from reaching Earth by the ionosphere. Short wave ul-
traviolet radiation is absorbed by the ozone-layer in the stratosphere, whilst longer
wave UV-radiation, visible light and infrared rays pass it.
The level of naturally occurring microwaves at the Earth’s surface is extremely
low. High frequency microwaves are stopped by the ionosphere, especially its D-
region. This function is of importance for the conclusions drawn in this presentation.
The Mammalian Brain in the Electromagnetic Fields Designed by Man 5
Natural extremely low frequency electromagnetic fields are formed by electrical
discharges in the atmosphere due to the resonance cavity formed by the surface of
the Earth and the charged ionosphere resonances occur. These resonance frequencies
are named after W. O. Schumann who already 1952 predicted their existence, and
were recorded in 1960 by Balser and Wagner.30)
The Schumann resonances at 7.8, 14, 20, 26, 33, 39, and 45 Hz21)−23) are exam-
ples of natural oscillating electromagnetic fields of importance. It is possible that
these resonances with their frequency predominantly at 7.8 Hz but also at 14-45 Hz,
have played — and play — a role in the tuning of the spontaneous frequencies of the
mammalian brain, where the frequency during relaxation is around 8 to 14 Hz, and
during concentration 14-30 Hz.
Natural extremely low frequency ELF magnetic fields are also generated by the
currents in the electrical discharges between clouds and the surface of the Earth.24)
The daily variation of these ELF magnetic fields is strongly correlated to variations
in the atmospheric magnetic field.25)
The always present geomagnetic field (GMF) of the Earth is a prerequisite for
life. It not only shields us from the solar wind, but also has direct functions for life
such as orientation of pigeons,26) plant branching, orientation of root branches and
shielding of the geomagnetic field causes biological alterations such as decrease of
the vital functions in bacteria and effects upon meristem (cf. stemcells in animals)
of seedling roots of pea, flax and lentil and electron microscopy reveals changes in
the mitochondrial structure.27)
Evidence has also been brought forward that we have endogenous internal rhythms
in blood pressure and heart rate, which are close to, however not identical to, the
period length of the rhythms in the solar wind. So, it has been proposed, that these
were installed genetically by natural selection at some time in the distant geological
past.28) It has also been shown that magnetic storms cause additional biological dys-
functions. Thus, bacterial bioluminescent intensity varies according to the amplitude
and duration of the MSs. Further, medical studies correlate MSs with anxiety and
irritability and lower attention and accuracy, with an increment of the probability
of road accidents29) and aviation accidents.30) Also, acute attacks of cardiovascular
diseases, such as myocardial infarction and stroke, become more frequent.31)
We have to conclude that the existing organisms are created to function in har-
mony with the abovementioned fields and forces which existed when life was born
3 billion years ago. And so was the situation until the generation of our grandpar-
ents. They invented the wonders of our modern life. Thus, in the late 19th century
mankind introduced the use of electricity. Until then the ELFs, extremely low fre-
quency electromagnetic fields, were represented on Earth principally only by the
Schumann resonances. But now Tesla constructed the induction motor, Morse intro-
duced the long-range telegraph, Bell the telephone, Edison developed the commercial
electrical networks and electricity spread around the globe. Marconi introduced the
wireless receiver 1896 and in the early 20th century long-wave radio and in the
1940-ies short-wave radio appeared.
Compared to the estimated natural background level of natural ELF magnetic
fields below 1 pT/Hz (10−12 T/Hz) for which the previous generations of human
6L. G. Salford et al.
beings had been exposed, the average exposure in the modern world is about 100
000 times higher!
§2. Microwaves
In 1964 Penzias and Wilson discovered the cosmic microwave background (CMB)
which fills the whole universe and which originates from the Big Bang. Also ongoing
cosmic processes in for example intergalactic gas clouds with temperatures of about
30◦K contribute to some cosmic microwaves. But microwaves are heavily attenuated
by the ionosphere and the atmosphere. Thus the natural electromagnetic background
radiation in radiofrequency and the microwave band is extremely low at the Earth’s
surface.
The integrated spectral distribution of the microwave background in space re-
sults in a power density of about 0.4 µW m−2. A great deal of this radiation is
thus reflected by the Earth’s magneto- and ionosphere or is absorbed by water and
other molecules in the atmosphere. A rough estimate of the power density of CMB
at the Earth’s surface varies from 10−21 to 10−14 Wm−2equivalent to 10−15–10−8c
µWm−2. This level of radiation is extremely low and extremely sensitive measuring
equipment is required for its recording.
Thus microwaves had so far been extremely low on Earth’s surface, but in the
1950-ies high frequency RF was introduced as FM and television and during the
very last decades, microwaves of the modern communication society spread around
the world for the first time and now exceed the natural levels by many orders of
magnitude (Table I).
Today one third of the world’s population owns the microwave-producing mobile
phones and an even larger number is exposed to the cordless RF emitting systems
(“passive mobile phoning”5)). To what extent are all living organisms affected by
these new, almost everywhere present radio frequency fields? And what will be the
effects of many years of continuing exposure?
Table I. Incident energy from a spectrum of sources of electromagnetic energy. These are not
actually measured values. They are guideline values set by authorities. (For microwave ovens
U.S. Food and Drug Administration since 1971). The actual standard 5 mW/cm2= 50 W/m2at
5 cm from oven surface, 0.5 mW/m2at 50 cm at 2.45 GHz corresponds to 10 W/m2= 2W/kg,
and 50 W/m2= 10 W/kg.
Source Energy flux density (W/m2)
Natural Background <10−14
Microwave oven, RF leakage standard
5 cm for surface 50
50 cm from surface 0.5
Cell telephone (2 GHz) public guideline 10
Cell telephone (850 MHz) public guideline 4.3
RF levels near cellular base antenna (calculated)∗)0.05
∗)Typical E-field levels in proximity to cellular telephone base stations (<200 m).32)
The Mammalian Brain in the Electromagnetic Fields Designed by Man 7
These questions are extremely important to answer. Our generation and our
children are the first to be exposed during a lifetime to the microwaves, which are
exponentially increasing underneath the ionosphere which was intended to prevent
their access to Earth, at least partially.
Scientists have studied the effects of ELF and MW since the 60-ies, and an
abundance of reports have emerged, especially during recent years, many of them
demonstrating significant effects upon biology and health, while others have failed
to show effects. In this communication we will summarize the results of some of
our work in the field since 1988 and also comment to a lesser extent upon the
work of other research groups. During recent years, several scientific reports in
respected journals have shown significant, but often weak, effects upon cells in vitro,
experimental animals and also humans (for reference see 33)-35)).
Recent epidemiological studies indicate that long term exposure might increase
the risk for some tumour forms (for review see 36)). In a Swedish case-control study
it was reported that the use of analogue and digital cellular telephones and cordless
phones was correlated to an increased risk for malignant brain tumours. Regarding
the use of digital cellular telephones, an odds ratio of 1.9 was observed and with a
>10-year latency period this odds ratio was increased to 3.6.37)
It has also been shown that mobile phone emission modulates (with increase in
some cases, and decrease in others) inter hemispheric functional coupling of EEG
alpha rhythms.38)
The mechanisms through which the electromagnetic fields exert their effect upon
cells and organisms are not well understood. This may be part of the reason why
the results of different laboratories diverge and it should be pointed out that it is
as important to reveal the mechanisms as it is to demonstrate their effects upon
biology. In this publication we also dwell at some length at the theoretical models
trying to explain the biological effects of EMF in relation to our own experiments
on EMF steering of calcium passage over spinach plasma vesicle membranes.
§3. The Blood Brain Barrier (BBB) of the mammalian brain
Since 1988 our group has studied the effects of RF electromagnetic fields upon
the blood-brain barrier (BBB) and we have collected an extensive experimental ex-
perience in this field. RF electromagnetic fields have been revealed to cause signif-
icantly increased leakage of albumin through the BBB of exposed rats as compared
to non-exposed animals — in a total series of about two thousand animals. We
have exposed rats to various magnetic and electromagnetic fields, as well 915 MHz
continuous wave (CW) as pulse-modulated at various repetition rates (50-200 pulses
per s), and we have confirmed these findings in our laboratory in follow-up studies
with real GSM-900 and GSM-1800 exposures.2),3),5)−7),39)
The mammalian brain is protected from exposure to potentially harmful com-
pounds in the blood by the blood-brain barrier (Fig. 3). Being formed by the vascular
endothelial cells of the capillaries in the brain, this hydrophobic barrier maintains
and regulates the very sensitively tuned environment within the mammalian brain.
The blood-brain barrier is a highly complex system, in which several kinds of
8L. G. Salford et al.
Fig. 3. The blood-brain barrier.
cells exert a wide range of functions. Some of the main characteristics are described
below.
- The cell-to-cell contacts between the capillary endothelial cells are sealed with
tight junctions, forming a permeability barrier, which is much more selective as
compared to the fenestrated sealing of other capillaries.
- The outer surface of the endothelial cells is surrounded by protrusions (end
feet) from astrocytes. Thereby, the endothelial cells and the neurons are connected
and also, a second hydrophilic barrier is formed. Also, the astrocytes are implicated
in the maintenance, functional regulation and repair of the blood-brain barrier.
- A bilayer basal membrane supports the ablumenal surface of the endothelial
cells. This membrane might also further restrict the passage of macromolecules into
the brain parenchyma.
- Pericytes are other periendothelial accessory structures of the blood-brain bar-
rier. These have capacity for phagocytosis as well as antigen presentation and in
fact, they seem to contribute significantly to the immune mechanisms of the central
nervous system.40)
In addition to these structural properties of the blood-brain barrier, there are
also several physiological characteristics of major importance, e.g. the high number
of mitochondria within the endothelial cells (five-fold higher as compared to muscular
endothelial cells of rats)41) and also, the low number of pinocytotic vesicles for nutri-
ent transport through the endothelial cytoplasm. These are properties, which speak
in favour for an energy-dependent transcapillary transport system. Of importance
in the context of the blood-brain barrier permeability restriction, is also the enzy-
matic barrier of the cerebral endothelium, which metabolizes drugs and nutrients
The Mammalian Brain in the Electromagnetic Fields Designed by Man 9
and thereby prevent their passage into the brain parenchyma.42)
Taken together, all these characteristics of the blood-brain barrier guarantee that
only those molecules, which are either hydrophobic (such as oxygen, nitric oxygen
and steroid hormones), or bind to specific receptors (such as certain amino acids and
sugars), can pass freely from the blood circulation out into the brain parenchyma.
Additionally, there is also a weight-selectivity, where particles of a larger molecu-
lar weight are more effectively excluded from passage over the blood-brain barrier.
Also, active transport out from the brain parenchyma and metabolization of certain
drugs, made possible by an intact blood-brain barrier, stabilises and optimises the
environment surrounding the neurons of the mammalian brain.
In a number of pathological conditions, such as epileptic seizures, sepsis and
severe hypertension, the integrity of the blood-brain barrier is disturbed. The sensi-
tively tuned balance within the brain parenchyma is thereby disrupted. This might
lead to cerebral oedema, increased intracranial pressure and in the worst case, irre-
versible brain damage. Also, potentially carcinogenic molecules can gain free access
to otherwise protected areas of the mammalian brain. Of importance to remember,
is also, that transient openings might be harmful enough to result in permanent
tissue damage.43)
In conclusion, an intact and fully functioning blood-brain barrier is essential for
the proper function of the mammalian brain.
Rectangular pulsed RF were generated by switching the MW generator (900
MHz) on and off with a rectangular pulse train of various repetition frequencies
(4-217 Hz). We started our studies on albumin passage over the BBB a repetition
frequency of 16 Hz and then with its harmonies of 4, 8 and also 50 Hz, which was
felt relevant, as it is the standard voltage of the European power supply, with a
carrier wave of 915 MHz. At an early stage also 217 Hz modulation was added
as this was the frequency of the then planned GSM system. In all experiments
endogenous substances such as albumin and fibrinogen, which occur naturally in the
blood circulation, were used for the detection of BBB leakage, which is identified by
anti-rat albumin rabbit antibodies and rabbit anti-human fibrinogen.
This work was published in 19943) and 19976) and comprised sham or 915 MHz
exposure for in most cases 2 hours (both CWs and pulsed modulated waves). These
results, based on 246 rats 1994 and more than 1,000 rats 1997 (the majority EMF
exposed and about 1/3 sham-exposed) concluded that there was a significant differ-
ence between the albumin extravasation from brain capillaries into the brain tissue
between the differently exposed groups and the controls. It is important to point
out that though all animals in the 1997 series (and basically all of our experiments)
are inbred Fischer 344 rats, only at the most 50% of the identically exposed animals
display albumin extravasation (in CW animals and somewhat less in the other ex-
posed animals). Even the sham exposed animals had some albumin leakage though
only in seventeen per cent as a mean of all controls and at a lesser extent. The
detection of leakage in unexposed animals presumably is due to our very sensitive
immune histological methods.
The most remarkable observation was that exposure with whole-body average
power densities below 10mW/kg gave rise to a more pronounced albumin leakage
10 L. G. Salford et al.
than higher power densities, all at non-thermal levels. If the reversed situation were
at hand, we feel that the risk of cellular telephones, base-stations and other RF
emitting sources could be managed by reduction of their emitted energy. The SAR
value of around 1 mW/kg exists at a distance of more than one meter away from
the mobile phone antenna and at a distance of 150-200 metres from a base station.
This has led us to coin the concept passive mobile phoning for all non-users who are
exposed.5)
The maximally allowed SAR-value for occupational exposure is 10 W/kg, and 2
W/kg is the maximally allowed SAR-value for public exposure. At a frequency of 900
MHz, these values are reached at power densities of 22.5 W/m2for maximally allowed
occupational exposure, and 4.5 W/m2for maximally allowed public exposure. That
is, 1 W/kg corresponds to 2.25 W/m2at a frequency of 900 MHz.
In many studies of pharmacological effects in connection with RF exposure,
response is only seen at a certain dose range, and not at higher or at lower dosages.
This is named “the inverted U-function”. A similar RF response characteristic has
been observed by us, seen as a more pronounced albumin leakage at lower than
at higher power densities. According to Adey, this kind of dose response might
constitute the basis for window effects observed in connection to RF exposure.44)
In the majority of our studies, EMF exposure of the animals has been performed
in transverse electromagnetic transmission line chambers (TEM-cells)(for reference
see 2),3),5)-7),39),45),46).) These TEM-cells are known to generate uniform elec-
tromagnetic fields for standard measurements. In each TEM-cell, two animals can
be placed, one in an upper compartment and one in a lower compartment. The ex-
perimental model allows the animals, which are un-anaesthetized during the whole
exposure, to move and turn around in the exposure chamber, thus minimising the
Fig. 4. Pathological leakage around brain capillaries demonstrated by immuno assaying against
blood albumin. Fischer 344 male rat (# 3987, weighing 292 g) exposed to 1899 MHz CW
microwaves in an anechoic chamber for 2 hours at SAR ≈2mW/kg. Ten minutes after this
exposure, the animal was anaesthetised and sacrificed.
The Mammalian Brain in the Electromagnetic Fields Designed by Man 11
effects of immobilization induced stress, described by Stagg et al.47)
It is important to point out that the position of the animals in upper or lower
compartments does not affect the magnitude of observed albumin leakage. Also, we
have concluded, with our total series of more than two thousand exposed animals,
that there is no difference in the sensitivity to EMF exposure between male and
female animals as far as albumin leakage is concerned.
Our initial findings of albumin leakage have been repeated by others,48) with 900
MHz exposure of rats for 4 hours at brain power densities ranging from 0.3 to 7.5
W/kg. Another group, working in Bordeaux, and led by Prof Pierre Aubineau, has
also demonstrated evidence of albumin leakage in rats exposed for 2 hours to GSM-
900 MHz at non-thermal SAR-values of 0.12, 0.5 and 2.0 W/kg, using fluorescein-
labelled proteins. The results were presented at two meetings49) and are very similar
to ours, described above.
Support for our findings that low intensity GSM 900 MHz electromagnetic fields
influence the BBB is also found in the in vitro proteomic studies on a human en-
dothelial cell line by the group of Leszcynski.50),51)
§4. Neuronal damage
Our consistent findings of albumin passage over the BBB and spread in the
surrounding brain tissue with albumin uptake in the cytoplasm of neurons and glial
cells brought up the question whether this might lead to neuronal damage.
In a series of experimental situations, neuronal degeneration has been observed
in areas with BBB disruption and it has been suggested that BBB leakage is the
major reason for nerve cell injury such as that seen in dark neurons.52)
It has also been observed after intracarotid infusion of hyperosmolar solutions in
rats;53) in the stroke-prone hypertensive rat;52) and after acute hypertension by aortic
compression in rats.55) Further, epileptic seizures cause extravasation of plasma into
brain parenchyma.54) The cerebellar Purkinje cells are heavily exposed to plasma
constituents and degenerate in epileptic patients.55) This effect may, however, as
Fig. 5. Left: A rat in the upper exposure tray of a TEM-cell for 915 MHz microwaves. Right:
Block diagram of the 4 TEM-cell arrangement used in the experiments in Lund. A microwave
power generator is used for feeding the TEM-cells. A power splitter divides the power form
the RF generator into equal parts that are fed to each TEM-cell. The output from the cells is
terminated in a 50 Ohm dummy load.
12 L. G. Salford et al.
well be attributed to hypoxia. It has been postulated that albumin is the most likely
neurotoxin in serum.56)
In order to seek for neuronal damage in our experimental model, we exposed
Fischer 344 rats for 2 hours with non-thermal GSM at SAR values 120, 12 and 1.2
mW/kg.7) We made the remarkable observation that a significant (p<0.002) neuronal
damage is seen in rat brains 50 days after such an exposure.
It is notable, that we see areas in hippocampus and cortex of exposed animals
where the cytoplasm of neurons are filled with autologous albumin while neighbour-
ing neurons display the shrunken and dark state of a “dark neuron” which is a very
sick or dying neuron. It may be so that the leakage of albumin out in the neuropil
starts a deleterious process whereby more albumin leaks through the endothelium
and finally becomes too heavy a burden for the affected neurons. Hassel et al.57)
have demonstrated that injection of albumin into the brain parenchyma of rats gives
rise to neuronal damage. When 25 micro litres of rat albumin is infused into rat
neostriatum, 10 and 30, but not 3 mg/ml albumin causes neuronal cell death and
severe axonal damage. It also causes leakage of endogenous albumin in and around
the area of neuronal damage.
Findings similar to ours in the animals sacrificed late after exposure have been
reported in Wistar rats.58) Twenty-two female rats were exposed to a 900 MHz
electromagnetic GSM near-field signal for one hour a day for seven days. The peak
specific absorption rate (SAR) of the brain was 2 W/kg. This resulted in scattered
and grouped dark neurons in the cortex, hippocampus and basal ganglia, mixed in
among normal neurons with distributions of scores significantly different between
the control and the GSM exposure group (p<0.01).
In continued work we have proven our own finding from 2003 — in a study of 96
non-anaesthetized rats which were exposed or sham exposed for a duration of 2 hours
at specific absorption rates (SAR) of 120, 12, 1.2 and now also 0.12mW/kg. The
extravasation of albumin, uptake into neurons and occurrence of damaged neurons
were assessed 14 or 28 days later. Albumin extravasation and uptake into neurons
was significantly enhanced after 14 days, but not after 28. The occurrence of dark
neurons, on the other hand, was significantly enhanced only after 28 days. After 28
days, neuronal albumin uptake was significantly correlated to occurrence of damaged
neurons.8)
In ongoing and recently completed experimental work, we have studied lifelong
exposure to GSM 900 as well as the effects of short term exposure to GSM 900 and
1800 in living rats. Lifelong exposure to microwaves seems to be the future of the
young generation. Therefore, we have studied male and female Fischer 344 rats,
exposed for 2 hours to GSM 900, and sham exposed in our TEM-cells once a week
for 13 months. After this they were studied for cognitive functions and compared to
cage controls. Significant effects of exposure upon episodic memory function have
been demonstrated and published.9) In short, the cognitive functions were evaluated
in the episodic-like memory test. The GSM-exposed rats had significantly impaired
memory for objects and their temporal order of presentation (p=0.02). The detec-
tion of a place in which an object was presented, that is the spatial memory function,
was not affected by the GSM exposure. In rats, hippocampus is involved in aspects
The Mammalian Brain in the Electromagnetic Fields Designed by Man 13
comparable to human declarative memory, and is seems possible that the reduced
memory functions that we observed are correlated to hippocampal alterations in-
duced by the mobile phone exposure. Also, temporal order memory, depending on
cortical areas such as the perirhinal cortex in the medial temporal lobe, the prefrontal
cortex and the interaction between these areas, might explain the reduced temporal
order memory of the GSM exposed rats. Finally, after the memory tests had been
performed, all animals were sacrificed and the brains are now under examination for
albumin leakage, neuronal and glial damage and other signs of pathology.
The possibility that microwaves may affect our DNA has received increased at-
tention since recent epidemiological studies indicate that long term exposure (10
years mobile phone use) increases the risk for developing tumours in the exposed
brain hemisphere, both the benign vestibular schwannoma arising from the balance
nerve and the highly malignant glioblastoma multiforme.36),37),59) Regarding the de-
velopment of vestibular schwannoma, the relative risk seen ten years after the start of
mobile phone use, was 1.9 (with confidence interval 0.9-4.1).59) When only tumours
occurring at the same side of the head as the mobile phone had been normally used,
the relative risk increased to 3.9 (with confidence interval 1.6-9.5). In a pooled anal-
ysis of case-controlled studies on malignant brain tumours, cumulative life use of >
2, 000 hours of mobile phoning revealed an odds ratio of 3.7 (confidence interval of
1.7-7.7).60)
Studies of gene expression patterns in the living animal may elucidate also other
aspects such as effects on genes involved in membrane transport and other basal
functions of the living cell in situ.
In collaboration with Belyaev and his group we have exposed rats for 6 hours to
GSM-900 RFs at SARs of 0.4mW/kg and investigated the genetic expression from
cerebellar tissue. Alterations of genes encoding proteins for BBB functions were
observed.10)
We have now studied whether 6 hours of exposure to the radiation from a GSM
mobile phone at 30mW/kg has an effect upon the gene expression pattern in rat
brain cortex and hippocampus — areas where we have observed albumin leakage
from capillaries into neurons and neuronal damage. Microarray analysis of 31 099
rat genes, including splice variants, was performed in cortex and hippocampus of
8 Fischer 344 rats, 4 animals exposed to GSM for mobile communications electro-
magnetic fields for 6 hours in an anechoic chamber and 4 controls kept for the same
length of time in the same anechoic chamber without exposure. Gene ontology anal-
ysis of the differentially expressed genes of the exposed animals versus the control
group revealed interesting differences between exposed animals and controls. Genes
of interest for membrane transport show highly significant differences.11) This may
be of importance in conjunction with our earlier findings of albumin leakage into
neurons around capillaries in exposed animals and has also lead us to look into the
mechanisms behind these effects — see below under DNA Transcription process,
Solitons and Microwaves.
14 L. G. Salford et al.
§5. Mechanisms behind the effects of electromagnetic fields upon
biology
5.1. Interaction of ELF with calcium metabolism
Beyond what is described above, we have also performed experiments where an
increase of the Ca2+-efflux over plasma membranes has been observed in plasma
vesicles from spinach exposed to ELF.13)
We could show that suitable combinations of static and time varying magnetic
fields directly interact with the Ca2+-channel protein in the cell membrane, and we
could quantitatively confirm the model proposed by Blanchard.61)
Calcium has many important roles in all living organisms. Apart from its struc-
tural role in, for example, bone matrix, plant cell walls, and in stabilizing membranes,
it plays an essential role in cellular homeostasis, most notably as an intracellular
messenger.62) The free Ca2+ concentration in the cytosol is strictly kept at 0.1-0.2
µM, which is much lower than that found in the intracellular Ca2+-stores or the
extra-cellular space. The cytosolic free Ca2+ ion concentration has influence upon
growth and development of the organism and its daily functions as well as death in
apoptosis.62)
It has been suggested that the mechanism underlying alterations of Ca2+-fluxes
involves inducible changes of both static and time varying magnetic fields.63 The
studies of the effects on Ca2+-influx over cell membranes are of importance in the
perspective of human health, considering the crucial role of Ca2+-flux played in
cellular communications.
The mechanism, by which magnetic fields might interact with biological systems,
has been called magnetoreception. Different models try to provide the theoretical
framework explaining how this is made possible, and these models are also important
for future model-guided investigations of the magnetoreception.
In order to explore the mechanism for possible biological effects of the enhanced
ELF radiation environment, we investigated how the transport of Ca2+ ions over the
membrane of spinach plasma vesicles varies with frequency and amplitude of ELF
magnetic field exposure. Baur´eus-Koch et al.13) studied the calcium flux through
calcium channels in highly purified plasma membranes of spinach (Spinacia oleracea
L.).13)
A bio-resonance phenomenon was found where appropriate combinations of fre-
quency and amplitude have the potency to affect bio-membranes and their Ca2+ -ion
transport systems at various degrees and directions. With a static magnetic field
BDC = 37.0 ±0.5 µT we found resonances of BAC = 25.9 ±0.3 µT (peak), at the
frequencies of 7, 21, 24, and 31 Hz. The Ca2+ -ion efflux ratio at those exposure
conditions appears to deviate significantly compared to that of sham exposures.13)
Three Gaussian peaks with the same width of 2.5±0.4 Hz could be fitted through
the data points with peaks at the frequencies 20.9±0.3, 25.4±0.4, and 30.2±0.5 Hz
with a χ2value of 6.0. These frequencies correspond well to the resonance frequencies
20.7 Hz (Mnion,n= 1) 25.2 Hz (45 Caion,n= 1), and 31.1 Hz (Mnion,n= 1),
respectively.13)
The Mammalian Brain in the Electromagnetic Fields Designed by Man 15
With our Ca2+-efflux studies over plasma membranes as a basis, our research
was further extended into the field of magnetic resonance models; mainly the Ion
Parametric Resonance (IPR) Model as proposed by Lednev;64),65) in an attempt to
explain the occurrence of resonance frequencies. In short, Lednev’s model considers
the polarization of the oscillation of an ion bound to a protein in a combination of
static and time-varying magnetic fields.
In our studies of spinach vesicles, the calcium flux was modified at frequencies
that corresponded to resonance frequencies for non-hydrated ions of 40Ca2+ , Mn2+
and Mn3+. The resonance frequencies were linearly related to the strength of the
static magnetic field applied. The resonance frequency of 24 Hz could be attributed
to 45Ca2+ (n= 1) or 24Mg++ (n= 2). Lednev64) predicts an amplitude dependence
that follows the Bessel functions.
In our experiments, we concluded that the resonance could be attributed to
45Ca2+. However, as in the experiments performed by Blackman,66) a factor of two
had to be included in the argument of the Bessel function.
In 1996, Lednev65) modified his model, in order to avoid some of the problems
identified in the original theory.67) In this modified version the amplitude window is
described by the square of the Bessel functions. A fit to our data13) demonstrates
that the factor of two is not required as previously to fit the experimental data to
the theory.
Taken together, our experimental results of the interaction of ELF magnetic
fields with Calcium bound to proteins in the cell membrane fit extremely well with
quantum mechanical interaction models.61),63),68) Thus, we have shown that ELF
magnetic fields interact with Calcium and Manganese ions in plasma membranes at
specific frequencies in accordance to a quantum mechanical interaction model.13)
The search for the mechanisms behind the effect of electromagnetic interac-
tions with biological systems has continued. Another way to address the issue, as
compared to our model with the purified membrane system, with theoretical, phys-
ical models as a basis, is the biological examination of signalling pathways possibly
affected by magnetic fields. As has been shown by Sun et al.,68) a possible mech-
anism for the bioeffects produced by ELF-EMF exposure could be protein tyrosine
phosphorylation. 50 Hz power-frequency magnetic fields could activate the stress-
activated protein kinase (SAPK),70) however, not through the phosphorylation of the
upstream kinase of SAPK (SEK1/MKK4).71) Noise MF with certain intensity could
inhibit the biological effect induced by 50 Hz MF, as seen by the reduced activa-
tion of SAPK when noise and 50 Hz exposures were applied simultaneously.72) With
continued research of this kind, a mosaic of EMF target proteins might crystallize.
§6. Transmembral transportation — Solitons and microwaves
A major portion of this paper dwells on the passage of albumin from the brain
capillaries out into the surrounding brain and the cytoplasm of neurons and astro-
cytes, and the remarkable observation that it is the lowest energy levels that give
rise to the most pronounced albumin leakage.
The mechanisms by which the EMFs may alter BBB permeability are not well
16 L. G. Salford et al.
understood. At low field strengths, the effects on body temperature are negligible
and thus heating effects are not involved. It has been suggested that physicochemical
characteristics of membranes are changed.12) One of the great pioneers in the field,
Ross Adey discussed the mechanisms behind a possible direct, non-thermal effect
of RF radiation upon the central nervous system. He studied amplitude-modulated
radiofrequency fields and suggested in 1988 that co-operative processes in the cell
membrane might be reactive to the low energy of an electromagnetic field. This
oscillating field might result in changes of the membrane potential.74)
The question might find an answer within a theory which we hereby bring for-
ward
– the possible soliton function in membranes.
The word soliton emanates from John Scott Russell’s observation of the solitary
wave
In 1834, while conducting experiments to determine the most efficient design
for canal boats, this young Scottish engineer made a remarkable scientific discovery,
which he described in his “Report on Waves” after his first sighting of a soliton or
solitary wave, by Russell called a “Wave of Translation” on the Union Canal near
Edinburgh.73)
The migration of soliton energy in molecular systems was first considered by
Davydov and Kisluka75) by the use of a quantum coherent wave theory. Solitons
were considered important for energy transfer and storage in biological structures,
as described by Davydov76) and then by Fr¨ohlich,77) as coherent dipolar propagating
waves. These applications of quantum field theory to biological systems inspired
many theoretical physicists to study biological systems with a special interest fo-
cused upon tubulin. This filamentous protein is a fundamental building block of the
cytoskeleton matter.78),79) Microtubules are important components of the cytoskele-
ton, responsible for cellular organization and information processing.80) Microtubules
of the neurons in the brain might be active components of brain functioning and
information processing. Endogenous electromagnetic waves are considered to be
moving in the cavity of the microtubules, transporting and carrying information.
The relevant mechanism of electromagnetic wave interaction has been suggested
to be spontaneous breakdown of symmetry in the biological, well ordered struc-
tures. Such interaction occurs with the dipole moments of the molecules in the brain
microtubules.79)
Abdalla et al.81) studied the problem of information propagation in the brain mi-
crotubules, considering propagation of electromagnetic waves in a fluid of permanent
electric dipoles. The problem reduces to sine-Gordon wave equation in one space and
one time dimension. The energy balance of the voltage along with the neuronal pro-
jection and the microtubule z-axis, results in generation of solitons and propagation
of kinks or anti-kinks along the microtubule proto-filaments. The tubulin tails are
coupled to the dipoles of nearby water molecules at the microtubule surface and the
change of their conformational status at the place of the soliton twist. The standing
breather swinging at certain tubulin tail (or breather formed by 2-3 coupled swinging
tubulin tails) could catalyze microtubule attachment proteins (MAP) and promote
or inhibit the action of kinesin-proteins involved in the microtubule dynamics.82)
The Mammalian Brain in the Electromagnetic Fields Designed by Man 17
Another interesting result of the work of Abdalla et al.81) is the fact that the
frequency parameters, which showed up in the model, are compatible with the size
of microtubules of brain structures and with the transition period observed for the
so called conformational changes of the tubulin dimer protein (namely 1-100 GHz).
The applications of exogenous, electromagnetic waves in this frequency interval,
that coincide with that we use for wireless communication, interact with the endoge-
nous electromagnetic wave that might result in biological actions. This may be the
mechanism behind our observation of memory impairment in rats exposed to 0.9
GHz microwaves as described above.
Solitons as actors in biology thus have been discussed since the 1970-ies. The
effects in biological membranes have recently been brought to the fore by two re-
searchers at the Niels Bohr Institute in Copenhagen, T. Heimburg and AD Jackson
in their publication: “On soliton propagation in biomembranes and nerves”.83) They
write:”The lipids of biological membranes and intact biomembranes display chain
melting transitions close to temperatures of physiological interest. During this tran-
sition the heat capacity, volume and area compressibilities, and relaxation times all
reach maxima. Compressibilities are thus nonlinear functions of temperature and
pressure in the vicinity of the melting transition, and we show that this feature
leads to the possibility of soliton propagation in such membranes. In particular, if
the membrane state is above the melting transition, solitons will involve changes
in lipid state”. The authors discuss solitons in the context of several properties of
nerve membranes under the influence of the action potential, including mechanical
dislocations and temperature changes.
In a recent paper, the same authors support their hypothesis by pointing out
that the Hodgkin-Huxley model for nerve signal transduction never explained the
function of anesthesia. The soliton model on the other hand might give an answer.
They conclude that anesthetics lower the temperature at which lipids become solid,
making it difficult for the soliton waves to form. This should prevent nerves from
sending pain signals.
It is known that the action of general anaesthetics is proportional to their parti-
tion coefficient in lipid membranes (Meyer-Overton rule). This solubility is, however,
directly related to the depression of the temperature of the melting transition found
close to body temperature in biomembranes. Heimburg and Jackson proposed a
thermodynamic extension of the Meyer-Overton rule, which is based on free energy
changes in the system and thus automatically
incorporates the effects of melting point depression. This model accounts for
the pressure reversal of anaesthesia in a quantitative manner. Further, it explains
why inflammation and the addition of divalent cat-ions reduce the effectiveness of
anesthetics.84) (Charles Overton was professor of pharmacology at Lund University
1907-1930.)
The statement by Heimburg and Jackson is extremely interesting in reference to
an extensive and thorough work on pain perception and electromagnetic fields per-
formed by a research group in London Ontario since the early 1980-ies. (Their work
stimulated our group to visit London Ontario and to join in the field in 1988.) In a
recent review by the group, “Pain perception and electromagnetic fields”, it is con-
18 L. G. Salford et al.
cluded that the effects on pain, nociception (pain sensitivity) and opiate-mediated
analgesia (pain inhibition) constitute one of the most reproducible and reliable ef-
fects of EMFs with observed decrease in pain threshold (Del Seppia et al. 2007).
In early studies on the nociception of rodents, the animals were placed on a metal
surface at a standard temperature (50◦C for mice) and the time taken to respond to
the heat stimulus with a stereotypic averse withdrawal was recorded. The exposure
to a heterogenous time-varying magnetic field resulted in an enhanced basal noc-
turnal sensitivity and reduced levels of morphine induced analgesia in mice. Also
in connection with geomagnetic storms, mice were similarly less responsive to the
analgesic effect of morphine. Further studies, with the land snail Cepaea nemoralis,
showed that continuous EMF exposure induced hyperalgesia in a duration-dependent
manner (at exposure times ranging from 2 hours to 120 hours). It is also pointed
out that the increased pain perception by EMF may be a reason for the increasing
prevalence of pain problems in the modern society. (For further discussion of these
results, see 84).)
With the solid evidence collected from more than 50 publications, most of them
based on studies on the land snail, Cepaea nemoralis but also mice and rats, it
is tempting to give the solitons a chance in the search for, and definition of, the
physiological mechanisms involved.
Exposure to pulsed magnetic fields (MF) has been shown to have a therapeutic
benefit by increasing pain thresholds not only in animals, but also in humans. In
a recent study it was concluded that MF exposure does not affect basic human
perception, but can increase pain thresholds in a manner indicative of an analgesic
response.85)
We suggest that soliton models will be considered in studies on the relation
between pain, anaesthesia and electromagnetic field exposure. Further those models
could be applied to study the effect of EMF field on membrane permeability for
various molecules such as calcium and albumin.
It is striking that the soliton theory also may be instrumental in the explanation
of how the DNA transcription process is possibly influenced by the Microwaves:
§7. DNA Transcription process, solitons and microwaves
The Nishinomiya-Yukawa International & Interdisciplinary Symposium 2007
raised the question: What is Life? An obvious and simple answer could be: It
is DNA!
The DNA strand can be looked upon as an antenna resonating in the microwave
band 6GHz with its harmonics and subharmonics.14)−18) If this holds true, the dra-
matic situation might exist, that all living organisms have a receptor for the newly
constructed and world-wide man-made microwaves, leading to a direct effect upon
the function of DNA — in concordance with our experimental findings!
Screening of gene expression by microarray technology provides new powerful
means for the search for molecular pathways and to elucidate possible molecular
markers of response of brain cells to MWs. However, to our knowledge, only two
studies have been published on the effects of GSM microwaves upon the gene expres-
The Mammalian Brain in the Electromagnetic Fields Designed by Man 19
sion in the CNS after exposure of the whole organism.10),11) This material was first
presented at the 4th International Workshop, 16-20 October 2006, Crete Greece.87)
Those studies are described above and have shown that 6 hours of exposure to
GSM 900 MW (at the very low SAR value of 0.4 mW/kg) and 1800 MW (at SAR
value 30 mW/kg), to brain cells in vivo gives rise to highly significant alterations of
gene expressions in cerebellar, cortical and hippocampal cells.
These findings are supported by a series of recent publications where the influ-
ence of RF of the type emitted in GSM has been studied in vitro in different cell
cultures, proving effects upon gene expression in cultured human cells88)−90) and rat
neurons91) through non-thermal mechanisms.
In the search for a possible mechanism behind these effects of the man-made
microwaves upon living organisms, we have explored the effects of microwaves on the
DNA/RNA transcription process. In the following we bring forward the possibility
of a soliton mechanism in the interaction between microwaves and the DNA/RNA
transcription process.
§8. The DNA transcription process
The first step in genome expression is DNA transcription from the original DNA
template contained in the cell, is to make a copy — the RNA messenger — which
will then be used as a ‘master copy’ in determining protein sequences in accordance
with the genetic information. The evolutionary advantage of such a messenger is
obvious: in this way, the original DNA is opened — and thus less protected — for
as small a time as possible.92)
In the DNA transcription process, a specialized enzyme (RNA-Polymerase or
RNAP) binds to a specific site of the DNA double helix and unwinds it in a local
region of 15-20 bases, thus creating a “transcription bubble”; the RNAP and the
bubble travel then along the DNA, copying its sequence and producing a RNA-
Messenger to be later used to express genes or replicate the local sequence. This
process requires a very finely tuned coordination of the motion of RNAP — and
production of the RNA-Messenger — with the dynamics of the DNA double chain.
In the active phase of the process, the RNAP proceeds along the DNA chain at a
speed of several tens or hundreds of base pairs per second. Since each base pair is
linked by two or three hydrogen bonds, the energy involved in such a process, even
considering only the one to open (and close) the DNA chain, is of the order of at
least hundred, if not thousand, H bonds per second. This corresponds to about to a
power 300 fW (1 fW = 1 femto-W = 10−15 W).
§9. Solitons hiding in DNA and their role in RNA transcription
In a pioneering paper which appeared in 1980, Englander, Kallenbach, Heeger,
Krumhansl and Litwin suggested that nonlinear excitations in the DNA double chain
could be instrumental in this process and allow the motion of the transcription
bubble to occur at near-zero energy cost. In particular, as the fundamental motion
undergone by DNA nucleotides in this process is a roto/torsional one, they suggested
20 L. G. Salford et al.
Transcription Bubble. A schematic representation of a
transcription bubble in the elongation of an RNA
transcript. Duplex DNA is unwound at the forward end
of RNA polymerase and rewound at its rear end. The
RNA-DNA hybrid rotates during elongation.
(Englander et al., 1980)
Fig. 6. Solitons in transcription.
modelling the DNA molecule as a double chain of coupled pendulums; the relevant
nonlinear excitations would then be (topological) solitons pretty much like those,
well known in the sine-Gordon equation93) (Fig. 6).
Englander et al.93) concluded that precedent for a frequency w, of MHz in double
helices implies extended open segments with (L/l) = 10, compatible with the mobile
defect model hypothesized (Fig. 7). Experimental indications for processes as fast as
GHz exist, but imply very large open structures with (L/1) = 1000. Characteristic
attempt frequencies of MHz, on the other hand, seem to be more reasonable in
terms of hydrodynamic, melting, and NMR data. The overall activation energy for
forming solitons was estimated to 6 kcal/mol which corresponds to (L/l) = 100.93)
The binding energy of individual hydrogen bonds is in the same order of magnitude.
Nonlinear-waves in DNA was suggested by Polozov and Yakushevich94) to be in-
volved in the regulation of transcription.94) Prohofsky95) proposed that the hydrogen-
bond-stretch (HBS) bands of the double helix appear to be nonlinear enough to
support solitary-wave energy concentration. Coupling this fact to predictions of a
self-consistent theory of helix melting gives rise to speculations of a mechanism for
base pair melting in RNA transcription which is consistent with the known energy
needs of that process.95)
Guided by the idea of the order parameter of Landau, Zhou and Zhang96) anal-
ysed the structure and various nonlinear motions in DNA. They argued for the use of
four significant variables, i.e., the conformational, rotational, longitudinal and trans-
verse motions. Several sets of nonlinear discrete equations with more reasonable
Hamiltonian were established, and their solution of small amplitude (phonons) and
large amplitude (soliton or solitary waves) have been given. They speculated in the
possible significant implications in duplication, transcription and drug intercalation
in DNA.96)
The Mammalian Brain in the Electromagnetic Fields Designed by Man 21
Fig. 7. A mechanical analogue of the DNA double chain, as presented by Englander et al.92) Linear
chains of the bases (here modelled as pendulums, each with a mass m and length h, with a space
in between corresponding to l≈3.4 ˙
A) are connected by sugar-phosphate backbones (modelled as
springs). One strand of the DNA double helix is able to undergo torsional oscillations (angle θ)
about the sugar-phosphate backbone in the presence of the restoring gravitational force = m∗g.
A) The DNA double helix in its ground state.
B) Soliton excitation mode, with large-amplitude excursion of one of the pendulum. The exci-
tation is spread to the group of pendulums within the range of L.
Gaeta97) suggested that nonlinear excitations could play a role in the process of
DNA transcription, i.e. that the transcription bubble could correspond to a solitary
wave travelling along the chain, which the RNAP could then ‘surf’ in order to access
the base sequence with no energy to provide for opening the double helix. He dis-
cussed the general idea of providing a simple model for a specific DNA process, and
argued that despite the tremendous complexity of the DNA model, this approach is
not bound to fail. Recalling the main features of the model proposed by Yakushevich,
he mentioned some encouraging achievements and several limitations.97)
These limitations, however, more than being inherent to the model, are limi-
tations of the studies conducted so far. It is clear that the model is too simple to
be valid as it is. What is needed is to go ‘one step further’ in the Yakushevich
classification of DNA models, but only a more thorough analysis can focus on the
detailed refinements which are needed.98) In particular, Gaeta97) pointed out several
directions in which he suggested that it is necessary to generalize the model and to
investigate its behaviour, such as considering real nucleic acid base sequences and
microwave thermal effects.
22 L. G. Salford et al.
9.1. Dissociation phase transition in DNA
Bishop, Dauxois, and Peyrard proved the existence of a ‘dissociation’ phase
transition in DNA, considered as a one dimensional system.99)−103) Indeed it models
DNA as a one-dimensional chain, and by singling out one degree of freedom per base
— corresponding to ‘radial’ displacements along the axis joining the two bases of a
pair — that is, the degree of freedom thought to be the most relevant for the process
under study.
Their theory for DNA melting compares successfully to experimental data on the
detailed (spatiotemporal) dynamics of DNA melting. It can predict not only average
quantities, as should anyway be the case with a statistical mechanics approach, but
a spatiotemporal pattern.104)
9.2. DNA and microwave absorption
A nontrivial theory for dsDNA phonons and its associated nonlinear modes is
provided by the Peyrard-Bishop model104) whose Hamiltonian is given by:
HP B =
N
X
i=0
(P2
i
2m+k
2(xi+1 −xi)2+VH(xi)),
VH(y)=U0(exp(−y/λ)−1)2,
where pi=mviis the momentum of the ith base pair,
xiis the relative coordinate of displacement at each base pair,
viits velocity,
kis the harmonic coupling along each of the chains, and
VHrefers to the Morse potential representing hydrogen bonds between each base
pair.
Fits to experimental data reveal that the well-depth is about normal room tem-
perature (O(10-2 eV)). In a more realistic Peyrard-Bishop-Dauxois model the spring
constant kis allowed to vary along the double chain to reflect the requisite stacking
energy dependence.105)
In the presence of an electric field oscillating in time but spatially homogeneous
on the length scale of the dsDNA, we make the following replacement, which follows
from standard classical electrodynamics:
pi→pi−qiA(t)/c,
A(t) = −EOc
ω0
sin (ω0t),
where
qiis the charge at the ith bond,
Ais a component of the vector potential that exhibits solely a time-dependence,
cis the speed of light,
E0is the amplitude of the incident EM radiation, and
ω0is its frequency.
The charge could be electronic, or it could be a counter-ion adsorbed from the
The Mammalian Brain in the Electromagnetic Fields Designed by Man 23
aqueous, ionic solvent. We are primarily interested in small perturbations, with a
view to estimating at what level they become sinister.
Chivantis describes a dsDNA system, with the following Hamiltonian density,
which is the continuum version of the Peyrard-Bishop-Dauxois model.14),105)
HdsDN A =1
2h(1 −Λ(t)) (∂tφ(x, t))2+c2
D(φ(x, t) (∂xφ(x, t))2i+VH(φ(x, t))
c2
D(φ(x, t)) = c2
0(1 + ρexp(−2αφ(x, t)))
where
Λ(t) = α2sin(ω0t)2
α=q2βQ2σ2
mω2
0<1
cD(φ) refers to the extension proposed by Dauxois.100)
It causes a stiffening of the backbone as the hydrogen bonds fluctuate. This
stiffening reflects the stacking energy dependence of dsDNA. This extension was
found to be crucial in understanding the thermal denaturation of dsDNA
It is important to note that the solvent serves to siphon off energy from the
disturbance in a very sensitive way. Small changes in the coupling to the solvent
bath of phonons affect dramatically the breather modes excited by the EM fields.
Experiments where the coupling between the solvent and a DNA molecule is varied
will be extremely useful in directing the future development of the understanding of
EM effects on the dynamics of DNA.14)
The free energy needed to melt a GC base pair is generally accepted to be 3.5
kcal/mole and that for an AT base pair 1 kcal/mole. If inflow of this amount of energy
occurred, the net energy requirements of transcription would easily be met. The
reason to consider this form of energy transfer to the transcription complex is that
we believe it would involve the nonlinear hydrogen-bond stretch (HBS) modes. The
regime in which the bands of the torsional acoustic (TA) and hydrogen-bondstretch
(HBS) modes of DNA interpenetrate each other has been considered by Golo.16) He
proposes a simple model accommodating the helix structure of DNA and, within
its framework, to find a three-wave interaction between the TA and HBS modes.
This phenomenon is useful for studying the action of microwave radiation on a DNA
molecule. Thus, using Zhang’s mechanism of the interaction between the system
of electric dipoles of a DNA molecule and microwave radiation, he showed that the
latter could bring about torsional vibrations that maintain HBS vibrations.
Microwave radiation would maintain the HBS modes and there is no need for long
exposures of the sample to radiation. Golo16) estimated for the pure experimental
system, the critical power density, 100 mW/cm2, which is by orders of magnitude
larger than that officially prescribed, i.e., at 900 MHz 2W/kg corresponds to 4500
mW/m2or 0.45 mW/cm2, and at >2 GHz 10 W/kg corresponds to 10000 mW/m2
or 1 mW/cm2.16) The question is, however, if the theoretically derived limit of 100
mW/cm2is valid for in vivo exposure conditions. Thus there is still much more
research to be done before we might answer that question.
24 L. G. Salford et al.
§10. Conclusion
The first living organisms arose on Earth when it had existed for 1.5 billion
years. During the following 3 billion years, life on Earth was formed by, and ex-
isted in harmony, with the original physical forces such as gravitation, cosmic ir-
radiation, atmospheric electric fields and the terrestrial magnetism and the cyclic
celestial events. This was the world where evolution resulted in Homo sapiens, “the
wise man”. It took him 200 000 years to reach the level of knowledge where he could
dramatically alter the physical forces on Earth. During the last century the levels of
ELFs and MWs have been hugely increased in our habitat under the ionosphere.
Even if many studies have seen no effects of the EMFs upon biology, an abun-
dance of scientific reports in respected journals have shown significant, though often
weak, effects upon cells in vitro, in experimental animals and also in humans.
If the man made EMFs, such as those utilized in mobile communication, even
at extremely low SAR values, causes the users’ own albumin to leak out through the
BBB, which is meant to protect the brain, also other unwanted and toxic molecules in
the blood, may leak into the brain tissue. There they concentrate in, and damage, the
neurones and glial cells of the brain according to our studies. It cannot be excluded
that this, (especially after many years intense use) may promote the development of
autoimmune and neuro-degenerative diseases!
It is our generation who invented the microwave emitters. We now have an
imperative obligation to further investigate the links between EMF and biology in
order to prevent the possible detrimental effects of the microwaves. The concept of
solitons as active in membranes and RNA-transcription may be one key to open new
paths in the search — a search which must be an imperative not only for researchers
but also for states and organisations world-wide.
References
1) N. Cherry, Natural Hazards 26 (2002), 279.
2) L. G. Salford, A. Brun, J. Eberhardt, L. Malmgren and B. Persson, in Interaction Mecha-
nism of Low-Level Electromagnetic Fields in Living Systems, ed. B. Nord´en and C. Ramel
(Oxford University Press, Oxford, 1992), p. 251.
3) L. G. Salford, A. Brun, K. Sturesson, J. Eberhardt and B. Persson, Microscopy Research
and Technique 27 (1994), 535.
4) L. G. Salford, B. Persson and A. Brun, in Non-Thermal effects of RF Electromagnetic
Fields, ed. J. H. Bernhardt, R. Matthes and M. H. Repacholi (International Commission
on Non-Ionizing Radiation Protection, Munich, 1997), p. 131.
5) L. G. Salford,B. Persson, L. Malmgren and A. Brun, in T´el´ephonie Mobile - Effets Po-
tentiels sur la Sant´e des Ondes ´
Electromagn´etiques de Haute Fr´equence, ed. M. Pietteur
(Embourg, Belgium, 2001), p. 141.
6) B. Persson, L. Salford and A. Brun, Wireless Networks 3, 455.
M. Peyrard and A. R. Bishop, Phys. Rev. Lett. 62 (1997), 2755.
7) L. G. Salford, A. E. Brun, J. L. Eberhardt, L. Malmgren and B. R. R. Persson, Environ-
mental Health Perspectives 111 (2003), 881.
8) J. Eberhardt, B. R. R. Persson, L. Malmgren, A. Brun and L. G. Salford, “Blood-brain
barrier permeability and nerve cell damage in the rat brain 14 and 28 days after exposure
to microwaves from GSM mobile phones”, (submitted manuscript).
9) H. Nittby, G. Grafstr¨om, D. P. Tian, L. Malmgren, A. Brun, B. R. R. Persson, L. G.
Salford and J. Eberhardt, Bioelectromagnetics (2008a), published on line Dec. 2007.
10) I. Y. Belyaev, C. B. Koch, O. Terenius, K. Roxstrom-Lindquist, L. O. Malmgren, W. H.
The Mammalian Brain in the Electromagnetic Fields Designed by Man 25
Sommer, L. G. Salford and B. R. Persson, Bioelectromagnetics 27 (2006), 295.
11) H. Nittby, M. Krogh, G. Grafstr¨om, H. Berlin, G. Rehn, J. Eberhardt, L. Malmgren, B.
R. R. Persson, B. Widegren and L. G. Salford, “Exposure to global system for mobile
communications at 1800 MHz significantly changes gene expression in rat hippocampus
and cortex”, (submitted manuscript).
12) R. Shivers, M. Kavaliers, G. Teskey, F. Prato and R. Pelletier, Neuroscience Lett. 76
(1987), 25.
13) C. L. M. Baur´eus-Koch, M. Sommarin, B. R. R. Persson, L. G. Salford and J. L. Eber-
hardt, Bioelectromagnetics 24 (2003), 395.
14) S. M. Chitanvis, J. Polymer Science Part B-Polymer Physics 44 (2006), 2740.
15) G. S. Edwards, C. C. Davis, J. D. Saffer and M. Swicord, Phys. Rev. Lett. 53 (1984),
1284.
16) V. L. Golo, J. Exp.Theor. Phys. 101 (2005), 372.
17) E. W. Prohofsky, Bioelectromagnetics 25 (2004), 441.
18) C. T. Zhang, Phys. Rev. A 35 (1987), 886; Phys. Rev. A 40 (1989), 2148.
19) R. J. P. Williams, J. R. Soc. Interface 4(2007), 1049.
20) M. Balser and C. Wagner, Nature 188 (1960), 638.
21) W. O. Schumann, Z. Naturforsch. 7a (1952), 149.
22) P. V. Bliokh, A. P. Nicholaenko and Yu. Fillipov, in IEE Electromagnetic Waves Series
8(P. Peregrinus Ltd., Stevenage, 1980).
23) D. D. Sentman, Radio Science 22 (1987), 595.
24) D. D. Sentman, in Handbook of Atmospheric Electrodynamics, vol. I, ed. H. Volland (CRC
Press, Boca Raton, 1995).
25) R. E. Holzer and D. E. Deal, Nature 177 (1956), 536.
26) T. E. Dennis, M. J. Rayner and M. M. Walker, Proc. Biol. Sci. 274 (2007), 1153.
27) P. Galland and A. Pazur, J. Plant Res. 118 (2005), 371.
28) F. Halberg, G. Corn´elissen, P. Regal, K. Otsuka, Z. Wang, G. S. Katinas, J. Siegelova,
P. Homolka, P. Prikryl, S. M. Chibisov, D. C. Holley, H. W. Wendt, C. Bingham, S. L.
Palm, R. P. Sonkowsky, R. B. Sothern, E. Pales, M. Mikulecky, R. Tarquini, F. Perfetto,
R. Salti, C. Maggioni, R. Jozsa, A. A. Konradov, E. V. Kharlitskaya, M. Revillam, C.
Wan, M. Herold, E. V. Syutkina, A. V. Masalov, P. Faraone, R. B. Singh, R. K. Singh, A.
Kumar, R. Singhs, S. Sundaram, T. Sarabandi, G. Pantaleoni, Y. Watanabe, Y. Kumagai,
D. Gubin, K. Uezono, A. Olah, K. Borer, E. A. Kanabrockia, S. Bathina, E. Haus, D.
Hillman, O. Schwartzkopff, E. E. Bakken and M. Zeman, Biomed Pharmacother. 58
(2004), Suppl 1, S150.
29) P. Volpe, Photochem. Photobiol. Sci. 2(2003), 637.
30) F. I. Komarov, V. N. Oraevski ˘ı, Iu. P. Sizov, L. B. Tsirul’nik, Kh. D. Kanonidi, I. B.
Ushakov, P. M. Shalimov, M. V. Kimlyk and D. V. Glukhov, Heliogeophysical Factors
and Aviation Accidents 43 (1998), 742.
31) G. Villoresi, T. K. Breus, L. I. Dorman, N. Iuchi and S. I. Rapoport, Biofizika 40 (1995),
983, (Article in Russian).
32) R. Coray, P. Kr¨ahenb¨uhl, M. Reiderer, D. Stoll and G. Neubauer, Immissionen in
Salzburg. Bundesamt f¨ur Metrologie und Akkreditierung (Lindenweg 50, CH-3003 Bern-
Wabern, 2002).
33) G. Hyland, Lancet 356 (2000), 1833.
34) L. G. Salford, H. Nittby, A. Brun, G. Grafstr¨om, J. L. Eberhardt, L. Malmgren and B.
R. R. Persson, The Environmentalist 27 (2007), 493.
35) H. Nittby, G. Grafstr¨om, J. L. Eberhardt, L. Malmgren, A. Brun, B. R. R. Persson
and L. G. Salford, Electromagnetic Biology and Medicine (2008b). Article accepted for
publication.
36) M. Kundi K. Mild, L. Hardell and M. O. Mattsson, J. Toxicol. Environ. Health B: Crit.
Rev. 7(2004), 351.
37) L. Hardell, M. Carlberg and K. H. Mild, Environmental Research 100 (2006a), 232.
38) F. Vecchio, C. Babiloni, F. Ferreri, G. Curcio, R. Fini, C. Del Percio and P. M. Rossini,
Eur. J. Neuroscience 25 (2007), 1908.
39) L. G. Salford, A. Brun, J. L. Eberhardt and B. R. R. Persson, Bioelectrochem Bioenerg
30 (1993), 293.
40) W. E. Thomas, Brain Res. Rev. 31 (1999), 42.
26 L. G. Salford et al.
41) W. H. Oldendorf, M. E. Cornford and W. J. Brown, Ann. Neurol. 1(1977), 409.
42) J. F. Ghersi-Egea, A. Minn and G. Siest, Life Sciences 42 (1988), 2515.
43) T. E. O. Sokrab, B. B. Johansson, H. Kalimo and Y. Olsson, Acta Neuropathology 75
(1988), 557.
44) W. R. Adey, in Interaction Mechanism of Low-Level Electromagnetic Fields in Living
Systems, ed. B. Nord´en and C. Ramel (Oxford University Press, Oxford, 1992), p. 47.
45) J. Van Hese, L. Martens, D. De Zutter, C. De Wagter, L. Malmgren, B. R. R. Persson
and L. G. Salford, IEEE Transactions on Electromagnetic Compatibility 34 (1991), 292.
46) L. Martens, J. Van Hese, D. De Sutter, C. De Wagter, L. O. G. Malmgren, B. R. R.
Persson and L. G. Salford, Bioelectrochem Bioenerg 30 (1993), 73.
47) R. B. Stagg, L. H. Havel3rd, K. Pastorian, C. Cain, W. R. Adey and C. V. Byus, Radiat.
Res. 155 (2001), 584.
48) K. Fritze, C. Sommer, B. Schmitz, G. Mies, K. -A. Hossmann, M. Kiessling and C.
Wiessner, Acta Neuropathologica 94 (1997), 465.
49) F. T¨ore, P. E. Dulou, E. Haro, B. Veyret and P. Aubineau, Proc. the 5th International
congress of the EBEA, Helsinki, Finland (2001), p. 43; Proc. the 24th annual meeting of
the BEMS (2002), p. 61.
50) D. Leszczynski, S. Joenv¨a¨ar¨a, J. Reivinen and R. Kuokka, Differentiation 70 (2002), 120.
51) R. Nylund and D. Leszcynski, Proteomics 4(2004), 1359.
52) K. Fredriksson, H. Kalimo, C. Nordborg, B. B. Johansson and Y. Olsson, Acta Neu-
ropathologica (Berl) 76 (1988), 227.
53) T. S. Salahuddin, H. Kalimo, B. B. Johansson and Y. Olsson, Acta Neuropathologica
(Berl) 76 (1988), 1.
54) A. Mih`ay and B. Bozo‘ky, Acta Neuropathology 127 (1984a), 251; Acta Neuropathology
65 (1984b), 471.
55) T. E. Sokrab, H. Kalimo and B. B. Johansson, Epilepsia 31 (1990), 1.
56) S. Eimerl and M. Schramm, Neuroscience Lett. 130 (1991), 125.
57) B. Hassel, E. G. Iversen and F. Fonnum, Neuroscience Lett. 167 (1994), 29.
58) A. Ilhan, A. Gurel, F. Armuten, S. Kamisifi, M. Iraz, O. Akyol and S. Ozen, Clinica
Chimica Acta 340 (2004), 153.
59) S. L˝onn, A. Ahlbom, P. Hall and M. Feychting, Epidemiology 15 (2004), 653.
60) L. Hardell, M. Carlberg and K. H. Mild, Int. Arch. Occup. Environ. Health 79 (2006b),
630.
61) J. P. Blanchard and C. F. Blackman, Bioelectromagnetics 15 (1994), 217.
62) G. E. Kass and S. Orrenius, Environ. Health Perspect 107 (1999) (Suppl. 1), 25.
63) C. Fanelli, S. Coppola, R. Barone, C. Colussi, G. Gualandi, P. Volpe and L. Ghibelli,
FASEB J. 1(1999), 95.
64) V. V. Lednev, Bioelectromagnetics 12 (1991), 71.
65) V. V. Lednev, Biophysics 41 (1996), 224.
66) C. F. Blackman, J. P. Blanchard, S. G. Benane and D. E. House, Bioelectromagnetics 15
(1994), 239.
67) R. K. Adair, Bioelectromagnetics 13 (1992), 231.
68) V. V. Lednev, Electricity and Magnetism in Biology and Medicine (1993), p. 550.
69) W. J. Sun, Y. N. Yu, H. Chiang, Y. D. Fu and D. Q. Lu, Electro- and Magnetobiology
20 (2001a), 207.
70) W. J. Sun, H. Chiang, Y. D. Fu, Y. N. Yu, H. Y. Xie and D. Q. Lu, Electro- and
magnetobiology 20 (2001b), 415.
71) W. J. Sun, Y. N. Yu, H. Chiang, Y. D. Fu, H. Y. Xie and D. Q. Lu, Electro- and
Magnetobiology 21 (2002a), 97.
72) W. J. Sun, H. Chiang, Y. Fu, D. Lu and Z. Xu, Zhonghua Lao Dong Wei Sheng Zhi Ye
Bing Za Zhi 20 (2002b), 246, (Article in Chinese).
73) W. R. Adey, Prog. Clin. Biol. Res. 257 (1988), 81.
74) J. S. Russell, Report on Waves, 14th meeting of the British Association for the Advance-
ment of Science (BAAS, 1844).
75) A. S. Davydov and N. I. Kislukha, Phys. Status Solidi B 59 (1973), 465; Phys. Status
Solidi B 75 (1976), 735.
76) A. S. Davydov, Studia Biophysica 62 (1977), 1.
77) H. Fr¨ohlich, Int. J. Quantum Chem. 23 (1983), 1589.
The Mammalian Brain in the Electromagnetic Fields Designed by Man 27
78) S. R. Hameroff and R. C. Watt, J. Theor. Biology 98 (1982), 549.
79) E. Del Guidice, S. Doglia, M. Milani and G. Vitiello, Nucl. Phys. B 275 (1986), 185.
80) L. A. Amos and A. Klug, J. Cell Science 14 (1974), 523.
81) E. Abdalla, B. Maroufi, B. C. Melgar and M. B. Sedra, Physica A 301 (2001), 169.
82) L. A. Amos and D. Schlieper, Microtubules and maps. Fibrous Proteins: Muscle and
Molecular Motors (Elsevier Academic Press Inc., San Diego, 2005).
83) T. Heimburg and A. D. Jackson, Proc. Natl. Acad. Sci. USA 102 (2005), 9750.
84) T. Heimburg and A. D. Jackson, Biophysical J. 92 (2007), 3159.
85) C. Del Seppiaa, S. Ghionea, P. Luschib, K. P. Ossenkopp, E. Choleris and M. Kavaliers,
Neuroscience and Biobehavioral Reviews 31 (2007), 619.
86) N. M. Shupak, F. S. Prato and A. W. Thomas, Neuroscience Lett. 363 (2004), 157.
87) L. G. Salford, M. Krogh, G. Grafst¨om, H. Nittby, G. Rehn, H. Berlin, J. L. Eberhardt, L.
Malmgren, R. B. R. Persson and B. Widegren, Abstract for the 4th International Work-
shop: “Biological Effects of Electromagnetic Fields”, 16–20 Oct. 2006, Crete, Greece.
88) S. Lee, D. Johnson, K. Dunban, H. Dong, X. Ge, Y. C. Kim, C. Wing, ,N. Jayathilaka,
N. Emmanuela, C. Q. Zhou, H. L. Gerber, C. C. Tseng and S. M. Wang, FEBS Lett.
579 (2005), 4829.
89) S. Pacini, M. Ruggiero, I. Sardi, S. Aterini, F. Gulisano and M. Fulisano, Oncol. Res. 13
(2002), 19.
90) D. Remondini, R. Nylund, J. Reivinen, F. Poulletier de Gannes, B. Veyret, I. Lagroye, E.
Haro, M. A. Trillo, M. Capri, C. Franceschi, K. Schlatterer, R. Gminski, R. Fitzner, R.
Tauber, J. Schuderer, N. Kuster, D. Leszczynski, F. Bersani and C. Maercker, Proteomics
6(2006), 4745.
91) R. Zhao, S. Z. Zhang, G. D. Yao, D. Q. Lu, J. Huai and Z. P. Xu, Zhonghua Lao Dong
Wei Sheng Zhi Ye Bing Za Zhi 24 (2006), 222, (Article in Chinese).
92) W. Saenger, Principles of nucleid acid structure (Springer, Berlin, 1988).
93) S. W. Englander, N. R. Kallenbach, A. J. Heeger, J. A. Krumhansl and S. Litwin, Proc.
Natl. Acad. Sci. USA 77 (1980), 7222.
94) R. V. Polozov and L. V. Yakushevich, J. Theor. Biology 130 (1988), 423.
95) E. W. Prohofsky, Phys. Rev. A 38 (1988), 1538.
96) G. F. Zhou and C. T. Zhang, Physica Scripta 43 (1991), 347.
97) G. Gaeta, J. Biol. Phys. 24 (1999), 81.
98) L. V. Yakushevich, Quarterly Reviews of Biophysics 26 (1993), 201; Physica D 79 (1994),
77.
99) T. Dauxois and M. Peyrad, Phys. Rev. Lett. 70 (1993), 3935.
100) T. Dauxois, M. Peyrad and A. R. Bishop, Phys. Rev. E 47 (1993a), 684.
101) T. Dauxois, M. Peyrad and P. A. Bishop, Phys. Rev. E 47 (1993b), R44.
102) T. Dauxois, M. Peyrad and C. R. Willis, Physica D 57 (1992), 267.
103) M. Peyrard, T. Dauxois, H. Hoyet and C. R. Willis, Physica D 68 (1993), 104.
104) M. Peyrard and A. P. Bishop, Phys. Rev. Lett. 62 (1989), 2755.
105) N. Theodorakopoulos, T. Dauxois and M. Peyrard, Phys. Rev. Lett. 85 (2000), 6.
