[en] This report discusses a measurement of the isotopic composition of the cosmic ray nitrogen and oxygen. The detector is a stack of nuclear emulsions which was exposed in a balloon flight in northern Canada. The particle energy is 220-450 MeV/n. The particle masses are determined from photometric measurements of track widths. The standard deviation in the mass determination is calculated to 0.46 AMU for nitrogen and 0.50 AMU for oxygen. Special checks of possible errors originating from emulsion disturbances are made. The mass scale of nitrogen is calibrated with an accuracy of +- 0.1 AMU. The calibration is made by using the concept of restricted energy loss. The following results are obtained of the isotopic quotients extrapolated to the top of the atmosphere ¹⁷O/O=0.05+-0.03, ¹⁸O/O=0.08+-0.03, ¹⁵N/N=0.33+-0.09. (Auth.)

No abstract available

[en] An investigation of the isotopic composition of cosmic ray nitrogen and oxygen has been made. As a detector nuclear emulsions exposed in 1970 in a balloon flight from Fort Churchill have been used. The mass determinations are made on particles stopping in the emulsion stack and are based on the relations between residual range and track width measured with a nuclear track photometer. The results extrapolated to the top of the atmosphere are ¹⁵N/(¹⁴N+¹⁵N) =0.30+-0.11; ( ¹⁷O+¹⁸O)/(¹⁶O+¹⁷O+¹⁸O) =0.10+-0.05. (Auth.)

No abstract available

[en] An experimental investigation of the isotopic composition of cosmic ray nitrogen and oxygen is reported. The detector is a stack of nuclear emulsions exposed at about 3 g/cm² atmospheric depth. The mass determinations are based on photometric track width measurements on stopping nuclei. The standard deviation of the mass measurements is 0.46 AMU for nitrogen and 0.50 AMU for oxygen. The energy of the measured nuclei falls in the interval 220-450 MeV/nucleon at the top of the atmosphere. The measured isotopic quotients have been extrapolated to near interstellar space with standard methods. The extrapolated quotients are ¹⁵N/N = 0.34+-0.10, ¹⁷O/O = 0.02+-0.03, ¹⁸O/O = 0.07+-0.03. The nitrogen quotient extrapolated to the cosmic ray source shows that the nitrogen-oxygen abundances ratio is approximately the same in the source as in the solar system. The result has been compared with different hypotheses about the source composition and is found to be in best agreement with a hypothesis, which states that source matter has approximately the composition of the solar system and that a selection mechanism depending on the atomic properties of the elements is working in the source. (author)

[en] The possible ways to optimise the relation between diagnostic information and patient absorbed dose differ between nuclear medicine and X ray imaging. In nuclear medicine, very little has been done to find an optimal dosage of radiopharmaceuticals. Current nuclear medicine methods are discussed in the light of the recent ICRP Publications and the new EU Patient Directive. The paper also discusses how reference levels for administered activity may be derived from patient studies. In order to eliminate the most inappropriate choices (too low or too high activities), knowledge of the current statistical distribution of administered activities may be helpful. Different methods to estimate the amount of activity that should be administered to children of various body sizes to guarantee the same image quality as for adults are also discussed. Examples of current activity levels for common nuclear medicine procedures, indicating the state of the practice, are given. (author)

[en] The present paper discusses some experiences made in the process of evaluating control room system function during outage in nuclear power plants. It is recommended that a control room evaluation project should focus on both problem identification and problem solving. For the phase of problem solving, a technique called system groups are discussed. The method suggests that problem solving within the organization can be used within a group setting and that a wide variety of functions should be represented in the group. It is concluded that this method seems well suited to promote problem solving and that communication between different groups, risk awareness and management support are enhanced in system groups. (author). 2 refs

[en] Immunization of a goat with partially reduced and S-carboxymethylated plasmin B-chain-α²-antiplasmin complex resulted in a large population of antibodies with rather high specificity towards the complex. These antibodies do not react with plasminogen or plasmin in complex with other inhibitors than α²-antiplasmin. However, they react fully with native α²-antiplasmin, but a 200-fold higher concentration, as compared to plasmin-α²-antiplasmin complex, is needed to obtain a similar displacement curve in a double-antibody radioimmunoassay. The results indicate a conformational change in the vicinity of the reactive site in α²-antiplasmin, as a result of complex formation with plasmin. A method for determination of plasmin-α²-antiplasmin complex in plasma has been elaborated using the described radioimmunoassay. About 1.5 mg plasmin-α²-antiplasmin complex/l can be detected, which equals the condition when about 1% of the α²-antiplasmin in plasma is in complex with plasmin. In normal individuals plasmin-α²-antiplasmin complex could be detected only rarely. However, patients with acute processes, as evidenced by high fibrinogen levels, surgical patients postoperatively or patients with malignancy have often detectable levels. (author)

No abstract available

[en] Short communication