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[Radioprotective effect of low-intensity radio-frequency centimeter-band waves in lethal gamma irradiation].

Primary investigations have been carried out to determine whether low-intensity EMR of a cm range exerts the radioprotective effect. Prior to gamma-irradiation with doses LD100/30 and LD60/30 mice were exposed for 23 h to 2-8 GHz microwaves with a swing frequency of 12-14 Hz, at energy flow density of 5 +/- 1.5 mu Wt/cm2. Survival and time of death of mice were registered during a month. With absolutely lethal doses of gamma-irradiation, the application of SHF EMR delayed the time of animal death by 2.8-4.2 days and led in one of the experiments to 20% survival of mice. With doses in non-absolutely lethal range, the pretreatment of mice with EMR increased the survival by 20% in two experiments.

Animals↗
PubMed2006

Electromagnetic fields in offices.

With the increased use of electric and electronic equipment in our offices, our daily exposure to electromagnetic fields has become increasingly complex due to the great variety of the frequency content of the fields. Today focus has shifted from monitors as the dominating sources of electromagnetic fields to other electronic equipment, cabling, nearby substations, power lines and stray currents in buildings. In the last 5 years wireless communication has become common in our offices. These devices use radio frequency waves to communicate and are therefore sources of radio frequency fields in our offices. To a certain degree, they all add to the complicated issue of the extensive field frequencies found in offices. The exposure of office workers is generally considered to be low and not in conflict with the existing guidelines, but if a precaution approach is applied there are a number of measures that can be taken to reduce the electromagnetic fields in offices in order to obtain a good electrical environment.

Computer Communication Networks↗
PubMed1980

Heart rate, multiple body temperature, long-range and long-life telemetry system for free-ranging animals.

A long-range and long-life telemetry system for heart rate and multiple body temperatures from free-ranging animals is described. This system includes an implantable transmitter, external receiver-retransmitter collar, and a signal conditioner interface circuit to assist in demodulation of receiver tone outputs before data processing. The size of the implant is suitable for animals with body weights of a few kilograms or more; further size reduction of the implant is possible. The ECG is sensed by electrodes designed for internal telemetry and to reduce movement artifacts. The R-wave characteristics are then specifically selected to trigger a short radio frequency pulse. Temperatures are sensed at desired locations by thermistors and then, based on a heart-beat counter, transmitted intermittently via pulse interval modulation. This modulation scheme includes first and last calibration intervals for a reference by ratios with the temperature intervals for as much as a range of 0-50 degrees C with a resolution of 0.1 degrees C. Pulse duration and pulse sequencing are used to discriminate between heart rate and temperature pulses as well as radio frequency interference. The implanted transmitter might be used alone for experiments on animals that frequent particular locations within a large territory, on animals in virtually any laboratory situation, or on animals in moderate-sized enclosures, such as those in a zoological garden. The implanted transmitter is otherwise interfaced with the receiver-retransmitter collar that employs commercial tracking equipment to achieve the long-range transmission. The objective of the design was to achieve a high degree of experimental flexibility and overall high quality in performance. The system was tested in prototype form on a dog.

Animals↗