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61.
Reistad O Dowdall M Standring WJ Selnaes ØG Hustveit S Steinhusen F Sørlie A 《Journal of environmental radioactivity》2008,99(7):1032-1044
The spent nuclear fuel (SNF) and radioactive waste (RAW) storage facility at Andreeva Bay shore technical base (STB) is one of the largest and most hazardous nuclear legacy sites in northwest Russia. Originally commissioned in the 1960s the facility now stores large amounts of SNF and RAW associated with the Russian Northern Fleet of nuclear powered submarines. The objective of the present study was to map ambient gamma dose rates throughout the facility, in particular at a number of specific sites where SNF and RAW are stored. The data presented here are taken from a Norwegian-Russian collaboration enabling the first publication in the scientific literature of the complete survey of on-site dose rates. Results indicate that elevated gamma dose rates are found primarily at discrete sites within the facility; maximum dose rates of up to 1000 microSv/h close to the ground (0.1m) and up to 3000 microSv/h at 1m above ground were recorded, higher doses at the 1m height being indicative primarily of the presence of contaminated equipment as opposed to ground contamination. Highest dose rates were measured at sites located in the immediate vicinity of buildings used for storing SNF and sites associated with storage of solid and liquid radioactive wastes. Elevated dose rates were also observed near the former channel of a small brook that became heavily contaminated as a result of radioactive leaks from the SNF storage at Building 5 starting in 1982. Isolated patches of elevated dose rates were also observed throughout the STB. A second paper detailing the radioactive soil contamination at the site is published in this issue of Journal of Environmental Radioactivity. 相似文献
62.
63.
Eva Friis Møller Christian Marc Andersen Borg Sigrún H. Jónasdóttir Suree Satapoomin Cornelia Jaspers Torkel Gissel Nielsen 《Marine Biology》2011,158(3):677-688
The vertical distribution of copepods, fecal pellets and the fecal pellet production of copepods were measured at seven stations
across the Southern Indian Ocean from productive areas off South Africa to oligotrophic waters off Northern Australia during
October/November 2006. We quantified export of copepod fecal pellet from surface waters and how much was retained. Furthermore,
the potential impact of Oncaea spp. and harpacticoid copepods on fecal pellets degradation was evaluated and found to be regional substantial. The highest
copepod abundance and fecal pellet production was found in the western nutrient-rich stations close to South Africa and the
lowest at the central oligotrophic stations. The in situ copepod fecal pellet production varied between 1 and 1,000 μg C m−3 day−1. At all stations, the retention of fecal pellets in the upper 400 m of the water column was more than 99% and the vertical
export of fecal pellets was low (<0.02 mg m−2 day−1). 相似文献
64.
The physicist Walter M. Elsasser is mostly known for his work on the Earth's magnetism. Less attention has been paid to his efforts toward identifying what are the real differences between physical and biological systems. One essential distinction he recognized was that physical systems are largely homogenous while biological systems always revealed what he called ordered heterogeneity. Calculation of the possible configurations of such heterogeneous systems almost always leads to combinatorial explosions and to what Elsasser referred to as immense numbers. Such calculations have the consequence that any such systems are necessarily unique - mathematically speaking they represent one-sets.Another consequence is that immense numbers automatically introduce enormous uncertainty and indeterminacy into the system. Such systems are said to be ontically open. Applying this perspective to the genome and employing the notion of informational entropy reveals a common drive behind all development. This means that both conventional Darwinian evolution as well as the genomic mistakes that are believed to lie behind processes like aging and diseases can be interpreted against the background of one and the same process.At the same time the approach demonstrates how Darwinian evolution encompasses other notions such as Kauffman's “adjacent possible” (
[Kauffman, 1995] and [Kauffman, 2000]) and Eldrege's and Gould's “evolution via punctuated equilibria” (e.g.,
[Eldredge and Gould, 1972] and [Gould and Eldredge, 1977]). 相似文献
65.
How to Consider the Value of Farm Animals in Breeding Goals. A Review of Current Status and Future Challenges 总被引:1,自引:0,他引:1
H. M. Nielsen I. Olesen S. Navrud K. Kolstad P. Amer 《Journal of Agricultural and Environmental Ethics》2011,24(4):309-330
The objective of this paper is to outline challenges associated with the inclusion of welfare issues in breeding goals for
farm animals and to review the currently available methodologies and discuss their potential advantages and limitations to
address these challenges. The methodology for weighing production traits with respect to cost efficiency and market prices
are well developed and implemented in animal breeding goals. However, these methods are inadequate in terms of assessing proper
values of traits with social and ethical values such as animal welfare, because such values are unlikely to be readily available
from the product prices and costs in the market. Defining breeding goals that take animal welfare and ethical concerns into
account, therefore, requires new approaches. In this paper we suggest a framework and an approach for defining breeding goals,
including animal welfare. The definition of breeding goals including values related to animal welfare requires a multidisciplinary
approach with a combination of different methods such as profit equations, stated preference techniques, and selection index
theory. In addition, a participatory approach involving different stakeholders such as breeding organizations, food authorities,
farmers, and animal welfare organizations should be applied. We conclude that even though these methods provide the necessary
tools for considering welfare issues in the breeding goal, the practical application of these methods is yet to be achieved. 相似文献
66.
Petroleum exploration and production in the Barents Sea is a controversial topic. The Goliat field outside the northern coast of Norway will be the first offshore oil development in this region, with planned production start in 2013–2014. Avoiding major accidents at Goliat is critical; not only to reduce the risks to human lives and the environment, but also to gain political acceptance. Providing early warnings of major accidents for Goliat is one of the main objectives of the research project ‘Building Safety’. The objective of this paper is to describe the development of early warnings in the form of indicators. In addition, the paper includes an overview of current status of early warnings of accidents in other major hazard industries; the nuclear power industry, the chemical process industry, and aviation. Experiences from these industries, including lessons learned from recent major accidents, have been used as important input to the development of early warning indicators. 相似文献
67.
E. Steemann Nielsen 《Marine Biology》1978,46(3):185-189
Employing a special batch technique which involves extremely low concentrations of the alga Selenastrum capricornutum, it is shown that a growth rate of ca. 75% of optimum growth occurs at a concentration of 0.02 g-at N(NH4
+) l-1. The low concentrations of this N-source in the oligotrophic parts of the oceans (ca. 0.06 g-at l-1) thus give rise to a borderline deficiency. As the half-saturation constant (K
S) for growth was recorded at 0.05 g-at N(NO3
-), this ion can hardly be of much importance at the low concentrations present in these parts of the oceans. It is wrong to assert that N is the primary limiting nutrient. Phosphate also is found at concentrations giving rise to a borderline deficiency. 相似文献
68.
The population of small copepod species (approximately <1 mm) were investigated during an annual cycle in Disko Bay, western
Greenland. The small species considered were Acartia longiremis, Pseudocalanus spp., Oithona spp., Oncaea spp., Microsetella spp., and Microcalanus spp. Most of the small species were present in the surface waters year round and numerically dominated the community, and
in biomass from late summer and throughout winter. Oithona spp. was numerically the main contributor, while Pseudocalanus spp. dominated in terms of biomass. In the uppermost 50 m, maximum abundance, biomass and secondary production were observed
in late September after the phytoplankton production practically had terminated and the winter initiated. The free spawning
Acartia longiremis showed a strong seasonal fluctuation in biomass and egg production, in contrast to the egg carrying species Pseudocalanus spp. and Oithona spp. These had a long spawning season and maintained a more stable biomass year round. Secondary production was estimated
by three different ways: (1) based on the obtained specific egg production rates, (2) a temperature dependent equation, and
(3) a multilinear regression taking temperature, body weight and chlorophyll into consideration. The contribution of the small
species was insignificant when compared to the large Calanus species during the spring- and post-bloom. However, during late summer and winter, where Calanus had left the upper water strata for hibernation, the small species played a crucial role in the pelagic carbon cycling. 相似文献
69.
Impact of bias in predicted height on tree volume estimation: A case-study of intrinsic nonlinearity
Bias originating from intrinsic nonlinearity in nonlinear models is caused by excess curvature in the solution locus of parameter estimates derived from least squares procedures. Bias due to intrinsic nonlinearity varies according to sample size as well as model specification. This paper analyses consequences of fractionising data into smaller sub-samples. Based on measurements of stem diameter and total tree height from the first Danish national forest inventory, it is demonstrated how data splitting at random may cause the intrinsic nonlinear curvature to exceed the critical F-value. Application of a Taylor-series expansion shows that, for all practical purposes, the bias in predictions of individual tree volume (based on stem diameter and tree height) is negligible. To minimize residual variance, intrinsic curvature and, in turn, prediction bias, it is recommended that data be stratified according to site conditions, stand characteristics or other relevant criteria. Finally, the preferred model should exhibit close-to-linear behaviour. 相似文献
70.
Nieboer E Thomassen Y Romanova N Nikonov A Odland JØ Chaschin V 《Journal of environmental monitoring : JEM》2007,9(7):695-700
Urinary copper (Cu), nickel (Ni) and cobalt (Co) concentrations were determined for 127 Cu refinery workers (40 females, 87 males), with values of the 95% upper confidence interval of the geometric mean in nmol per mmol creatinine of 89 (Ni), 42 (Cu) and 3.4 (Co) for electrorefinery workers. In the pyrometallurgical departments, the corresponding concentrations were 37 (Ni), 99 (Cu) and 11 (Co). Female workers had higher Co urinary concentrations than males (p< or = 0.05) while no gender difference was observed for Cu and Ni. Inter-elemental correlations were moderate to weak. Based on the inhalable aerosol levels reported previously for the same workers, the observed urinary Cu concentrations were considerably lower than expected, relative to Co and Ni. This is interpreted in terms of the current understanding of Cu homeostasis. 相似文献