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A probabilistic analysis of atmospheric transport and deposition patterns from two nuclear risk sites-Kamchatka and Vladivostok-situated in the Russian Far East to countries and geographical regions of interest (Japan, China, North and South Koreas, territories of the Russian Far East, State of Alaska, and Aleutian Chain Islands, US) was performed. The main questions addressed were the following: Which geographical territories are at the highest risk from hypothetical releases at these sites? What are the probabilities for radionuclide atmospheric transport and deposition on different neighboring countries in case of accidents at the sites? For analysis, several research tools developed within the Arctic Risk Project were applied: (1) isentropic trajectory model to calculate a multiyear dataset of 5-day forward trajectories that originated over the site locations at various altitudes; (2) DERMA long-range transport model to simulate 5-day atmospheric transport, dispersion, and deposition of 137Cs for 1-day release (at the rate of 10(10) Bq/s); and (3) a set of statistical methods (including exploratory, cluster, and probability fields analyses) for evaluation of trajectory and dispersion modeling results. The possible impact (on annual, seasonal, and monthly basis) of selected risk sites on neighboring geographical regions is evaluated using a set of various indicators. For trajectory modeling, the indicators examined are: (1) atmospheric transport pathways, (2) airflow probability fields, (3) fast transport probability fields, (4) maximum possible impact zone, (5) maximum reaching distance, and (6) typical transport time fields. For dispersion modeling, the indicators examined are: (1) time integrated air concentration, (2) dry deposition, and (3) wet deposition. It was found for both sites that within the boundary layer the westerly flows are dominant throughout the year (more than 60% of the time), increasing with altitude of free troposphere up to 85% of the time. For the Kamchatka site, the US regions are at the highest risk with the average times of atmospheric transport ranging from 3 to 5.1 days and depositions of 10(-1) Bq/m2 and lower. For the Vladivostok site, the northern China and Japan regions are at the highest risk with the average times of atmospheric transport of 0.5 and 1.6 days, respectively, and depositions ranging from 10(0) to 10(+2) Bq/m2. The areas of maximum potentially impacted zones are 30 x 10(4) km2 and 25 x 10(4) km2 for the Kamchatka and Vladivostok sites, respectively.

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The reliability of a treatment process is addressed in terms of achieving a regulatory effluent concentration standard and the design safety factors associated with the treatment process. This methodology was then applied to two aqueous hazardous waste treatment processes: packed tower aeration and activated sludge (aerobic) biological treatment. The designs achieving 95 percent reliability were compared with those designs based on conventional practice to determine their patterns of conservatism. Scoping-level treatment costs were also related to reliability levels for these treatment processes. The results indicate that the reliability levels for the physical/chemical treatment process (packed tower aeration) based on the deterministic safety factors range from 80 percent to over 99 percent, whereas those for the biological treatment process range from near 0 percent to over 99 percent, depending on the compound evaluated. Increases in reliability per unit increase in treatment costs are most pronounced at lower reliability levels (less than about 80 percent) than at the higher reliability levels (greater than 90 percent, indicating a point of diminishing returns. Additional research focused on process parameters that presently contain large uncertainties may reduce those uncertainties, with attending increases in the reliability levels of the treatment processes.

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Rats were trained to discriminate the low-efficacy benzodiazepine receptor inverse agonist RU 33965 from vehicle in a two-lever discrimination task on a fixed ratio (FR) 20 schedule. Consistent discrimination was obtained at 0.5 mg/kg PO RU 33965. Both leptazol and stronger inverse agonists (FG7142, S-135, RU 34000) substituted for the cue. The weak inverse agonists/antagonists RU 33094, RU 34030, Ro 15-1788, and ZK 93426 also substituted for the cue with the latter two compounds being particularly potent. The agonist and partial agonists diazepam, RU 33203, and RU 39419 did not substitute for the RU 33965 cue but RU 39419 antagonised it. The full agonists diazepam and loprazolam only consistently antagonised the cue when given IP 5 min pretest. These data suggest that the RU 33965 cue results from its weak inverse agonist activity at benzodiazepine receptors, but kinetic factors must be considered when interpreting drug effects in discrimination studies.

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The thermal consequences of coal utilization are most meaningfully assessed in comparison with the form of power generation replaced by coal which is most likely nuclear. The different effects are influenced by siting decisions and the intrinsic thermal efficiencies of the two fuel systems. Nuclear power plants discharge 50% more waste Rheat to the atmosphere through cooling towers or to a water body than coal-fired plants. Coal-fired plants require about 2/3 as much water as nuclear power plants. Nearly every property of water is affected nonlinearly by temperature, and biological effects may amplify these changes because protein denaturation takes place more rapidly above 30 degrees C and these high temperatures affect bactericidal and viricidal activity of chlorine compounds. Usually algal populations change from a dominance of diatoms and green algae to dominance by blue-green algae. All organisms experience elevated metabolic rates at higher temperatures which may affect total energy needs, foraging ability, reproduction, migration and susceptibility to disease. Intake structures inevitably draw many organisms into the cooling system of a power plant, but the number and kind are influenced by its location, configuration, and mode of operation. Use of water recirculation systems reduces water use and with it, the number of organisms entrained. Mechanical damage in the cooling system to small organisms is generally low, but fish and their larvae and eggs may be seriously damaged. Discharge effects may also be severe but are generally local. The near field, where there are strong shear velocities and rapid temperature changes are particularly stressful to fish, and stringent limitations on the timing and strength of discharges may be required to reduce these stresses to nondamaging levels. Off-stream cooling systems may increase cloudiness, ground fog, precipitation, temperature and local winds, but these effects generally extend no further than 1000 m even in winter. There is considerable potential for using condenser cooling water for agricultural and aquacultural purposes such as irrigation, frost protection, undersoil heating, greenhouse heating and climate control. However, over the next few decades little of this waste heat is likely to be used creatively. The thermal consequences of implementing NEP are locally serious but do not pose regional problems. Creative use of the waste heat for aquaculture, agriculture, cogeneration, and power for energy intensive industries can be a powerful means of mitigating undesirable effects.

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The topical application of antibiotics and anti-inflammatory agents is used to reduce inflammation of the middle ear mucosa and irradicate infection. Many of the antibiotic and anti-inflammatory preparations so used contain compounds known to be or are potentially ototoxic. Eighteen antibiotic, antibacterial, antifungal and anti-inflammatory compounds and four commonly used solvents were screened for the absence of ototoxicity and inflammation to the middle ear mucosa. All compounds were injected intra-tympanically and sensory hair cells loss recorded graphically. Inflammation of the middle ear mucosa was assessed macroscopically. Of the 18 compounds only three, penicillin, carbenicillin and nystatin were free of hair cell toxicity and inflammatory effects on the middle ear mucosa. Only one of the commonly used solvents was free of side effects.

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Four compounds, prednisolone, sodium phenobarbitone, azathioprine and orotic acid, were tested for their ability to inhibit galactosamine induced hepatitis in the rat. Prednisolone offered total protection at doses of 100 mg/kg and above; sodium phenobarbitone and orotic acid modified the response to galactosamine and azathioprine was without effect.

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An examination of the hepatotoxicity of d-galactosamine has been made in the golden hamster and the mouse and the results compared to those previously investigated in the rat. The order of species found susceptible to the hepatotoxic effects of d-galactosamine was golden hamster greater than rat greater than mouse.

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Percutaneous insertion of a Swan-Ganz catheter through the internal jugular vein is presumed to have resulted in lodgement of the catheter tip in the wall of the internal carotid artery.

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1. The effect of d-galactosamine hydrochloride on the livers of rats was observed by measuring serum transaminase levels and histological examination. 2. Galactosamine caused dose related liver cell damage when given i.p. and s.c. but was ineffective when given orally. 3. The time of maximum effect was 24--48 h after administration. 4. The liver cell damage was modified by the oestrus cycle in female rats. 5. Galactosamine when given in proportion to body weight tended to be less effective as body weight increased.

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The diversity of a planktonic foraminiferal assemblage on the ocean floor depends on the state of preservation of that assemblage. As dissolution progresses, species diversity (number of species in the assemblage) decreases, but compound diversity (based on relative species abundance) first increases and then decreases; species dominance first decreases and then increases. The reason for these changes is that the species most susceptible to solution deliver moresediment to the ocean floor than do species with solution-resistant shells, possibly because the more soluble tests are produced in surface waters, where growth and production are greatest.

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