During the last few years, telemedicine based on simple, low-cost technology has increased significantly in the Arkhangelsk region of north-west Russia. Specialists at the regional hospital of Arkhangelsk are diagnosing patients from local hospitals 600-700 km from the capital. A still-image system is used for emergency cases. The same technology, along with telephones with loudspeakers, is also used to provide distance learning at the regional hospitals of Arkhangelsk and Tromso. This article describes the results from the telemedicine collaboration between the University Hospital of Tromso and health-care institutions in Arkhangelsk, and discusses the experience gained.

The brightness of backscattering radiation intensity for the lungs, liver, bone under in skin and muscle of a rabbit has been investigated by a fiber-optic design of special construction at the laser wavelengths 0.63, 0.83, and 1.15 micrometers . A satisfactory agreement between the brightness backscattering radiation intensity and the reflection coefficient for a single layer of the blood, liver, skin and muscle is observed. It permits using the previously proposed asymptotic solution of the theory of radiation transfer for weakly absorbing multilayer structures

Observations of the gamma-ray pulsar PSR 0833-45 in the constallation Vela, with the Gamma 1 telescope on board the Gamma Astrophysical Station, from August to October 1990 (approximately 300 h of observations) are reported. The light curve is obtained, the shape of which agrees with that of the COS B group. The measured flux of pulsed gamma rays with an energy exceeding 50 MeV is (1.6 +/- 0.2) . 10(-5) cm-2 . sec-1.

The telescope ‘Gamma-1’ is designed to investigate cosmic gamma rays in the energy range from 50 MeV to 5000 MeV. The geometrical sensitive area of the telescope amounts to 1500 cm2, the angular resolution in each direction is equal to 1.2° at the energy 300 MeV and is about 20′ when including a coded mask in the telescope, the energy resolution changes from 70% at 100 MeV to 35% at 550 MeV. The characteristics of the telescope and its systems have been determined by the Monte-Carlo method as well as by accelerator calibrations. Discrete sources at the intensity level of 10−7 quanta cm−2 s−1 may be recorded in a year of observations with the gamma-ray telescope ‘Gamma-1’ with a source location accuracy of ≈ 10 arc min.

The ‘Gamma-1’ telescope has been developed through a collaboration of scientists in the USSR and France in order to conduct γ-ray astronomical observations within the energy range from 50 to 5000 MeV. The major characteristics of the telescope were established by Monte-Carlo simulations and calibrations made with the aid of electron and ‘tagged’ γ-ray beams produced by an accelerator, and these have been found to be as follows: the effective area for photons coming along the instrument's axis varies from about 50 cm2 at Eγ = 50 MeV to approximately 230 cm2 at Eγ ≥ 300 MeV; the angular resolution (half opening of the cone embracing 68% events) is equal to 2.7° at Eγ = 100 MeV, and 1.8° at Eγ = 300 MeV; the energy resolution (FWHM) varies from 70% to 35% as the energy of the detected photons increases from 100 to 550 MeV; the telescope's field-of-view at the half-sensitivity level is 300–450 square degrees depending upon the spectrum of the detected radiation, and the event selection logic. Proceeding from the thus obtained characteristics it is demonstrated that a point source producing a photon flux J (Eγ ≥ 100 MeV) = 3 × 10-7 cm-2 s-1, can be detected with a 5σ significance by observing it during 106 s at the level of the Cygnus background, and a source having intensity J (Eγ ≥ 100 MeV) = 10-6 cm-2 s-1 can be detected to within a mean square positional accuracy of about 15′.

Measurement of gamma ray telescope plates is discussed. The graduated measurements of the angular resolution of wide gap spark chambers using photographic, video and vidicon information gathering schemes are presented.

The development of the gamma ray telescope is investigated. The wide gap spark chambers, used to identify the gamma quanta and to determine the directions of their arrival, are examined. Two systems of information recording with the spark chambers photographic and vidicon system are compared.

A scientific model of the wide-gap spark chamber which constitutes the central part of the Soviet-French high energy gamma-ray telescope “GAMMA 1” has been exposed to a tagged gamma-ray beam at DESY, Hamburg in 1976.