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1.
Marko S. Markov 《The Environmentalist》2007,27(4):457-463
The interest toward clinical application of magnetic and electromagnetic stimulation increases worldwide. Numerous publications
discussed the possibility exogenous magnetic and electromagnetic fields to initiate effects on various biological processes,
which are of critical importance for healing of different injuries and pathologies. Today, magnetic and electromagnetic fields
are increasingly utilized for treatment of various musculoskeletal injuries and pathologies. For musculoskeletal injuries
and post-surgical, post traumatic and chronic wounds, reduction of edema is a major therapeutic factor in the acceleration
of pain and stress relief, and thus contribute to healing processes. Electromagnetic and magnetic fields appear to be unique
in their safety during clinical use. The application of this new modality will be facilitated by searching for biophysical
mechanisms of action as well as by establishing exact dosimetry of application. In that respect basic science research needs
to be developed in parallel with clinical applications. Magnetotherapy provides a non-invasive, safe, and easy method to directly
treat the site of injury, the source of pain and inflammation, and other types of injury. Unfortunately, there are many obstacles
that magnetotherapy has to overcome—both from the mainstream medicine as well as from the manufacturers and distributors of
magnetic devices. The physical principle of magnetism as well as the physiological bases for the use of magnetic field for
tissue repair are subjects of this review. 相似文献
2.
Summary Despite of decades of successful worldwide use of magnetic/electromagnetic field therapy, the answer to the question of possible
mechanisms of action is still lacking. Scientific reports of successful therapeutic use of magnetic/electromagnetic fields
are worldwide; however, our understanding of the underlying mechanism is limited. This paper presents a new hypothesis that
therapeutic benefit of magnetic fields might result from effects that originated on the level of important systems in human
body. It is known now that the life is an electromagnetic event in aqueous medium. Therefore, an appropriate choice of magnetic
and/or electromagnetic field may be expected to initiate systemic changes that result in efficacious effects distant from
the point of application. Observations of this phenomenon have been reported in at least two forms: (1) neutralization of
the pain experience distant to the point of magnetic field exposure; and, (2) various alterations of T-lymphocytes in response
to pain and to magnetic fields. Extrapolating these observations to the level of blood-vessel system, one might hypothesize
that a “healthy” cell does not respond as readily to the applied fields as do abnormal cells (which are in a disease or injury
state). 相似文献
3.
Marko S. Markov 《The Environmentalist》2007,27(4):465-475
Magnetic and electromagnetic fields are now recognized by the 21st century medicine as real physical entities that promise
the healing of various health problems, even when conventional medicine has failed. Today magnetotherapy provides a non-invasive,
safe, and easy method to directly treat the site of injury, the source of pain and inflammation, and other types of diseases
and pathologies. Millions of people worldwide have received help in treatment of musculoskeletal system, as well as pain relief.
Pulsed electromagnetic fields are one important modality in magnetotherapy and recent technological innovations, such as Curatron
pulsed electromagnetic field devices, offer excellent, state of the art computer controlled therapy system. In this article
the development, state of the art and future of pulsed electromagnetic field therapy are discussed. 相似文献
4.
It is well recognized that a trigger point is a functional, rather than an anatomical, entity. It is known that a significant
fraction of both acute and chronic pain experience is myofascial in nature. This paper is aimed to discuss the potential of
using permanent magnets placed over the trigger points, which are associated with that referred pain, to be a tool for pain
relief. This approach is even more important in patients with various disabilities and experiencing chronic sacro-iliac and/or
low back pain. It appears that the trigger points represent a plausible physiological/tissue “window” and/or pathways, which
allow the magnetic fields to penetrate through physiological barriers, and thus returning injured tissues to the homeostatic
state. These “tissue windows” represent physiological “entrance points” for eventual exogenous stimulations, mainly physical
by nature, to enter the body. There is evidence that the application of magnetic fields (via permanent magnets) on trigger
points is more effective for pain relief as compared to application to other body surface area. The systemic effects at which
the results are manifested at sites distant from application area is also considered when discussing effects of magnetic fields
applied on trigger points. Ion transport is considered as central to the integrity and proper functioning of nerve excitability
and muscle contraction. Any disruption of their normal function would directly and markedly affect human neurosensory and
neuromotor performance. Biophysical phenomena associated with modification of ion transport are in the range of weak stimuli.
Therefore, electrophysiological changes in the functions of the so-called ion channels, are among the more (perhaps the most)
sensitive indicators to detect and quantify physiological effects of electromagnetic fields. 相似文献
5.
Lyubina Vesselinova 《The Environmentalist》2012,32(2):249-255
The importance of the assessment of the electromagnetic fields /EMF/ background as a health risk factor for the physiotherapy
personnel is discussed in this paper. Wide frequency and amplitude ranges as well as large variety of design prescribed in
the rehabilitation program form complicated work conditions. In this paper, we attempt to present and classify this specific
work environment, i.e., low intensive EMF background with non homogenous frequency and modulation characteristics, stochastic
changes running during day, ground or even underground units’ placement and professional specifics, i.e., chronic EMF expositions,
personnel’s trunk and hands exposure, dose-measurement absence, lack of program for prevention and prophylaxis for the assessment
of the relatively insufficiently elucidated potential of EMF as a harmful factor for medical staff. Our “Study of the biological
effects of the EMF among medical staff from PRM wards—potential of risk reduction”/initialized in 1999/and the original survey
card structure are presented in general here first. It has been shown the importance to extend the “native” studies among
homogenous professional groups, two of them presented there, as well as the study of the biological effects of EMF in their
different aspects, especially taking into account the elevated levels of ionizing and non-ionizing radiation in the environment.
This includes the special attention on the exposure of medical staff from PRM units and creation of adequate methods for prevention
of unnecessary exposure to these physical factors. 相似文献
6.
Summary Since IARC classified ELF magnetic field as Possibly Carcinogenic to Human the fear from 50/60 Hz magnetic field exposure
had been increased to the state of public “panic”. Subsequently, environment quality preservation organizations increased
their pressure on their government to adopt the “precautionary principle” and to reduce the allowable ELF Magnetic Field exposure
to much lower values than are recommended by ICNIRP-1998. As an example the present Environmental Ministry in Israel recommendation
is to lower the ELF Field exposure to 10 mG averaged over 24 h.
As a result of this stringent exposure guideline imposed by the government, electrical engineers who are involved in the deployment
and installation of large and medium electrical utilities, such as overhead power lines, transformers, UPS systems, electrical
public transportation, switching stations, etc., are much more aware to the need to employ special measures and methods for
reducing the magnetic fields that might be emitted from such utilities.
There are few computer codes that are capable of analyzing with great accuracy magnetic and electric fields surrounding single
phase and three phase electrical utilities in a 3-D system. The best presentations of the analysis results are by equi-value
contours depicting electric and magnetic fields. This graphical presentation is a powerful design tool that enables better
deployment and installation design aided to reduce the magnetic field emissions from high-power electrical utilities.
This paper describes the various types of graphical presentations available for ELF field contours, the dependent and independent
variants and parameters, magnetic field animation for optimization of power line installation and routing, and finally an
example that demonstrates the usefulness of the graphical presentation tools. 相似文献
7.
8.
The use of magnetic fields (MFs), in general, and electromagnetic fields (EMFs), in specific, as therapeutic modalities is
becoming very common. In the USA, EMFs are mostly used in orthopedics, followed by pain relief and the wound-healing arena.
Even though a substantial literature exists worldwide, we are still lacking the accepted comprehensive mechanism(s) of action.
In general, it is thought that the best therapeutic effects are achieved when the stimulation is applied directly to the target
area. Since the beginning of this century, however, more and more evidence has been collected indicating that effects of the
MF stimulation may also be observed at site(s) different from the site of application of the signal. A primary purpose of
this paper is to propose a link between the systemic and direct effects. The functional units known as trigger points are
discussed as possible “doors” allowing the stimulation to be delivered to the target tissue/organ. A second purpose is to
suggest some possible modes of action. 相似文献
9.
Hodgkin–Huxley model, describing generation of action potentials in axons’ membranes, has been used for appreciation of the
possible mechanisms of electromagnetic fields influence on neurons’ electrical activity. It follows from the carried calculations
that flowing through an axon of the external current pulses, which have an area of rise, an area of DC, and an area of drop,
does not influence own excitation pulses passage if periods of rise and drop are slope enough. Depending on the external current
parameters, own excitation pulses may not be influenced or may be suppressed at greater velocity of rise and drop of an external
current. Moreover, induced excitation pulses appear at definite parameters of an external current. In the case, when at passage
through an axon of an external current, own excitation pulses follow one by one (paired pulse facilitation), and the second
pulse may be suppressed if its level will not be increased additionally in comparison with the case of an external current
absence. It is possible that such increase happens “automatically” as a result of “tuning” (adaptation) of axons to the conditions
of flowing through them of an external current. It may be an explanation of the phenomena observed in experiments. 相似文献
10.
Marko S. Markov 《The Environmentalist》2012,32(2):121-130
In 1988 I published a paper “Electromagnetic fields—a new ecological factor” (Markov 1988). There was no internet and very few cell phones were available. It was not even fear from the hazard of the power lines.
However, I want to cite the beginning of this paper: “The contemporary conditions of life put man in dependence of the complex
of physical influences on the environment and in the first place—of the electromagnetic fields. The rapid development of science
and technology has resulted in the introduction of many new devices and technologies in industry, agriculture, and everyday
life. On the other hand, during their phylogenetic and ontogenic development, the living organisms are continuously exposed
to the influence of different biotic and abiotic factors. The physical factors are included in the first group, and the entire
evolution of life is connected with an adaptation to the action of these factors.” Could I repeat this statement nearly a
quarter of century later? Sure, I will. The only difference would be that I will speak not only for electromagnetic fields,
but for green-house effects, global warming, volcano eruption, and radiation disasters. I would also discuss the noise and
vibration to which people are exposed from early days to the very end of their life traveling with private vehicles or public
transport. 相似文献
11.
Epidemiological studies suggesting the possibility of harmful effects on human (specifically children’s leukaemia) due to
long-term exposure to magnetic fields of extremely low frequency (e.g. 50/60 Hz) and relatively low values (i.e. over the
microtesla range) have stirred high activity in the topic of magnetic field mitigation. To reduce these fields, it is common
to use passive metal screens (e.g. plates made of aluminium or steel). To design them, effective and fast numerical computations
are highly desirable. In this article, a method is presented, which computes various parameters of screens in a given shielding
problem and yields magnetic field distribution and shielding factors. The method takes into consideration the 3D field distribution
and is able to solve systems with large aspect ratios (thin thickness in comparison with its other dimensions); this is a
common problem where other methods such as finite elements often experience difficulties. The presented method computes separately
the field inside and outside the screens. Afterwards, the solutions are “stitched” together along the border of the subregions.
Two practical examples are given of the developed numerical method. 相似文献
12.
Conflicts over how to “scale” policy-making tasks have characterized environmental governance since time immemorial. They
are particularly evident in the area of water policy and raise important questions over the democratic legitimacy, economic
efficiency and effectiveness of allocating (or “scaling”) tasks to some administrative levels as opposed to others. This article
adopts a comparative federalism perspective to assess the “optimality” of scaling—either upward or downward—in one issue area,
namely coastal recreational water quality. It does so by comparing the scaling of recreational water quality tasks in the
European Union (EU) and Australia. It reveals that the two systems have adopted rather different approaches to scaling and
that this difference can partly be accounted for in federal theoretical terms. However, a much greater awareness of the inescapably
political nature of scaling processes is nonetheless required. Finally, some words of caution are offered with regard to transferring
policy lessons between these two jurisdictions. 相似文献
13.
Marko S. Markov 《The Environmentalist》2011,31(2):89-96
Natural and man-made magnetic and electromagnetic fields are important factors in the contemporary life. The paper discusses
the role of environmental magnetic and electromagnetic fields in origin and evolution of life. A brief review of the characteristics
of Earth magnetic field, Earth magnetosphere, and their role as a shield for cosmic radiation follows. The role of endogenous
and exogenous magnetic fields is discussed in respect of the clarification of the potential hazard and benefit of electromagnetic
fields. The second part of the paper discusses the mechanisms of detection and response to exogenous electromagnetic fields,
as well as threshold versus window hypothesis for mechanisms of interactions. Finally, the necessity of accurate dosimetry
at the target site and the importance of relevant research and clinical protocols in studying biological responses are pointed
out. 相似文献
14.
Occupational exposure to radiofrequency (RF) and static magnetic fields at magnetic resonance imaging (MRI) suites is of continuing
concern to personnel who routinely work in this environment. Questions regarding the levels of occupational RF and static
field exposure have increased with the increasing demand for anesthetics to be administered in this environment. The present
study was thus designed towards addressing the above-mentioned problem by gaining information regarding exposure levels of
clinical personnel at MRI units in South Africa. Three 1.5 MRI units in Bloemfontein, South Africa were utilized to evaluate
the exposure of clinical personnel to the electromagnetic fields present in the MRI environment over a period of time and
during different clinical MRI procedures. Three rounds of measurements of RF fields in the MRI environment were done. All
the three measurement rounds were focused on the low frequencies, 5 Hz–32 kHz, as well as on the high frequencies, 300 kHz–40 GHz.
First round measurements were done to establish the background of the RF fields in and around the magnet room during an MRI
examination. Second round RF field measurements were done at a specific location, 1 m away from the bore on the right-hand
side of the bed, in the MRI room. The third round measurements were of the same format as the second round, but the specific
location was against the magnet bore. Two pieces of Narda Safety Test Solution instruments, the EFA-300 and EMR-300, were
used to measure the electromagnetic and magnetic exposure fields generated from the MRI scanners. Results of the measurements
indicate that the electromagnetic fields measured during different clinical procedures do not exceed the International Commission
on Non-Ionizing Radiation Protection (2000) guidelines in these units. Results from round two and three showed that the RF
and gradient exposure 1 m and up against the bore entrance does not exceed these guidelines (rms average over 6 min). Ongoing
new developments in MRI scanning create the need for continuously monitoring exposure of patients and workers to the EMF fields
in the MRI environment. 相似文献
15.
Y. R. Mikayelyan N. S. Baghdasaryan A. K. Nikoghosyan S. V. Barseghyan S. N. Ayrapetyan 《The Environmentalist》2012,32(2):179-187
The effects of extremely low-frequency electromagnetic field (ELF EMF) and ELF-modulated millimeter waves (MMW) on physicochemical
properties of physiological solution (PS) at different environmental medium were studied. The existence of frequency “windows”
at 4 Hz and 8 Hz frequencies of ELF EMF and ELF-modulated MMW which have different effects on heat fusion period (HFP), hydrogen
peroxide (H2O2) formation and oxygen (O2) content of water solution and different dependency on temperature, background radiation (BGR) and illumination was shown.
The obtained data allow us to suggest that cell bathing medium serving as a target through which the biological effects of
ELF EMF and ELF-modulated MMW on cells are realized is extra sensitive to environmental factors. Therefore, the variability
of experimental data on EMF biological effects, obtained in different laboratories can be explained by different environmental
conditions of experiments, which very often are not considered adequately. 相似文献
16.
Barbara Skorupinski Heike Baranzke Hans Werner Ingensiep Marc Meinhardt 《Journal of Agricultural and Environmental Ethics》2007,20(1):37-52
This paper focuses on experiences from a case study dealing with the Swiss type of a consensus conference called “PubliForum”
concerning “Genetic Technology and Nutrition” (1999). Societal and ethical aspects of genetically modified food meanwhile
can be seen as prototypes of topics depending on the involvement of the public through a participatory process. The important
role of the lay perspective in this field seems to be accepted in practice. Nevertheless, there is still some theoretical
controversy about the necessity and democratic legitimacy of participatory processes in general, and especially about those
dealing with technological or environmental problems (sustainable development) concerning society. From an ethical point of
view, a lot of heterogeneous problems concerning contents and procedures of public participation can be pointed out, not only
on the theoretical level but also in practice, e.g., concerning the communication process between laypersons and experts.
The intention of our paper is to give hints and to clarify criteria that support the communication process leading to a dialog
of autonomous citizens and which especially consider ethical aspects in the field. One important result is that there must
be an orientation for all members of a consensus conference having clear rules and knowing their different roles that support
transparency, credibility, and fairness of the whole procedure and a “good product”: a substantial final document or citizens’
report.
This paper presents results of the project Ethical Bio-TA Tools as funded by the European Commission, DG Research, under FP5,
Quality of Life Programme. 相似文献
17.
In order to develop small islands, not only must a vital agricultural system be maintained, but the range of opportunities
for tourism must be increased with respect to both the seaside and the environmental features of the rural landscape. As an
alternative to the traditional and economically declining ones, many innovative production processes can be identified, but
their success depends on their interaction with the physical, biological, economic and social environment. In order to identify
the main nodes and the most critical interactions, so as to increase the probability of success of a new productive process,
a methodological approach based on the science of complexity is proposed for the cultivation of capers (Capparis spinosa L.) on the island of Pantelleria. The methodology encompasses the identification of actors and factors involved. the quantitative
evaluation of their interactions with the different stages of the productive process, and a quasiquantitative evaluation of
the probability that the particular action will be performed successfully.
The study of “traditional,” “modernized,” and “modernized-sustainable” processes, shows that the modernized-sustainable process
offers mutually reinforcing opportunities in terms of an integrated development of high-quality agricultural products and
the enhancement of environmental features, in conjunction with high-efficiency production techniques, in conjunction with
high-efficiency production techniques, in a way that suits the development of Pantelleria. There is a high probability of
failure, however, as a result of the large number of critical factors. Nevertheless, the present study indicates which activities
will enhance the probability of successful innovation in the production process. 相似文献
18.
Benefits-based management seeks to provide recreation benefits for recreation participants by managing the physical environments
in which recreation occurs. This study investigates the relationship between benefits desired by visitors and the physical,
social, and managerial characteristics of settings that facilitate realization of recreation benefits. Data such as perceived
benefits from recreation experiences, setting attributes that significantly influenced perceived benefits, and sociodemographic
variables were collected from 376 visitors to Sorak-san National Park in the eastern part of the Korean peninsula. Cluster
analysis was used to group visitors' desired benefits into 12 domains: relationship with nature/scenery, escaping pressure,
learning about nature, family togetherness, introspection, exploration, autonomy/achievement, being with friends, leading
others, skills/learning, risk taking, and meeting/observing new people. Multiple regression was used to link benefit domains
with the characteristics of settings. The social attribute of recreation settings was linked to eight of the ten benefit domains.
There were two statistically strong multiple regression correlations: (1) between domain of “relationship with nature /scenery”
and the attributes “forest/water,”“attractive nature,” and “facility/maintenance” and (2) between the domain of “escaping
pressure” and the attributes “attractive nature” and “social.” The results of this study are useful to managers in their efforts
to provide recreation opportunities for visitors to achieve beneficial outcomes. 相似文献
19.
The new recommendations of WHO and EC for legislation in Europe and other countries concerning non-ionizing radiation (NIR)
health and safety include exposure limits that are very debatable. ICNIRP Guidelines propose exposure limits for electromagnetic
fields in the frequency range up to 300 GHz based on short-term exposures and on thermal effects. The new EC proposal for
optical and laser safety legislation includes classification of sources of radiation—both lasers and other optical sources,
but not requirements for the methodology of classification. On the other hand, many new requirements have been set by the
WHO publication “Model Legislation for EMF Protection” concerning the responsibilities in the field of EMF health and safety.
Many specialists in the field of developing exposure limits have positions very far away from the proposed of the ICNIRP Guidelines
philosophy. The results are different approaches in developing standards and exposure limits, and differences more than 100
times in maximal permissible levels. We, the Bulgarian Program Committee on NIR, try to organize working groups and discuss
different philosophy for developing exposure limits for more than 10 years. This paper exposes our position in this area. 相似文献
20.
Crifasi RR 《Environmental management》2005,36(5):625-639
“A skyscraper is as natural as a bird’s nest” –Alan Watts
For millennia, people have altered freshwater ecosystems directly through water development and indirectly by global change
and surrounding land-use activities. In these altered ecosystems, human impacts can be subtle and are sometimes overlooked
by the people who manage them. This article provides two case studies near Boulder, Colorado that demonstrate how perceptions
regarding these ecosystems affect their management. These examples are typical of lakes and streams along the Front Range
of Colorado that are simultaneously natural and social in origin. Although natural, many of the region’s freshwater ecosystems
are affected by ongoing ecologic, hydrologic, chemical, and geomorphic modifications produced by human activity. People and
nature are both active participants in the production of these freshwater ecosystems. The concept of “hybridity,” borrowed
from geographers and social scientists, is useful for describing landscapes of natural and social origin. Hybrid freshwater
ecosystems are features of the humanized landscape and are derived from deliberate cultural activities, nonhuman physical
and biological processes, and incidental anthropogenic disturbance. Our perceptions of “natural” freshwater ecosystems and
what definitions we use to describe them influences our view of hybrid systems and, in turn, affects management decisions
regarding them. This work stresses the importance of understanding the underlying societal forces and cultural values responsible
for the creation of hybrid freshwater ecosystems as a central step in their conservation and management. 相似文献