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91.
Assessments of current and future development paths require comprehensive sets of indicators covering all essential aspects. From a holistic systems point of view, most currently proposed indicator sets are incomplete and deficient. Assessments of sustainable development require a full representation of the satisfaction states of the “basic orientors” (=fundamental interests) of constituent sector systems, and of their contribution to basic orientor satisfaction of the total system. Basic orientors are value dimensions (existence, effectiveness, freedom of action, security, adaptability, coexistence) emerging from a self-organizing system's interaction with its environment, and its fundamental properties (normal environmental state, scarce resources, variety, variability, change, other systems). Basic orientors are also reflected in human emotions, societal punishment, psychological and social needs, life styles, and values emerging in self-organization of artificial life. The relative weight assigned to basic orientors of partner systems is a question of ethics. Based on these concepts, a general scheme for finding a “complete” set of indicators of viability and sustainability is derived, and it is applied to deriving a comprehensive set of indicators of sustainable development for society and its sector systems (infrastructure, economic system, social system, individual development, government, environment and resource system). The method can be applied at different levels of complexity and regional resolution. A full set of regional indicators for sustainable development is presented, a method for compact assessment of development paths using orientor stars is described, and the approach for application at the community level is outlined.  相似文献   
92.
Oral vaccination of foxes (OVF) is a powerful tool to combat rabies in wildlife, and large parts of western Europe have been freed from rabies using this tool. Nevertheless, the success of OVF, given with the number of campaigns needed to eliminate the disease, depends on many factors. This article for the first time focuses on and assesses difference in OVF with respect to the spatial setting of vaccinated areas with time. The size of the areas vaccinated with time and the size of the overlapping area of consecutively vaccinated areas are particularly considered. In order to integrate these two aspects into one single figure, an Area Index is proposed ranging between 0 and 1. A statistical analysis indicates that the number of campaigns needed for rabies elimination significantly decreases on condition that the total rabies endemic area is consecutively treated right from the beginning of oral vaccination. Hence, from an economical and environmental point of view, vaccination areas should be selected the way that guarantees an Area Index close to 1. The concept of an Area Index, as described here, is a useful tool not only in the context of OVF, but it could also be used for other control schemes against infectious diseases in wildlife.  相似文献   
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ABSTRACT: The determination of optimum reservoir operating rules for reservoirs with multiple conflicting objectives is still a difficult task - despite many publications in this field. In this paper a three-step Multi Objective Decision Making (MODM) method is presented, the emphasis of which is placed on the necessity to make the work easy for the decision maker, which many MODM techniques fail to achieve. The method is applied to the development of a compromise optimum operating rule for a multi-purpose reservoir. In the first step of the method stochastic DP is chosen which is combined with the “weighting method” allowing combination of various objectives into one objective function. By systematically varying the weights for the objectives a large number of pareto optimum reservoir operating rules is generated. In the second step of the method the performance of all these operating rules is tested with the aid of a model simulating reservoir operation. The results are statistically analyzed and the reliabilities for attaining the various objectives are computed. The third step of the model applies another MODM technique which allows the decision maker - in a computer dialog - to select his optimum reservoir operating rule from the large number of pareto optimum solutions generated in step 1. Here he can specify his preferences for the various objectives. For this purpose two alternative MODM techniques are offered: Compromise Programming and the SEMOPS method. Their performance is shown along with the generation and selection of operating rules for the multi-objective Wupper reservoir system in Germany.  相似文献   
98.

Background and Scope

The marine shipping lanes have become the most important path for the invasion of foreign aquatic organisms. The increasing global trade results in an increase in the number of marine vessels. Without any protective measures, with every ship carrying foreign organisms the risk of biological invasions will rise.

Results

The International Martime Organization (IMO) of the United Nations developed a convention to reduce the transfer of organisms with ballast water. After the entry-into-force of this convention the fleet of the world has to be equipped with effective ballast water management technology before 2016. This article discusses potential options for action. To comply with the limit values of the ballast water convention, the current state of the art demands the use of active substances. Any decision on the approval of active substances used for ballast water treatment and the environmental impact assessment lies with the IMO. Proposed to day are UV-radiation, active chlorine, active oxygen, the creation of biocides through electrolysis and a change in gases contained in the ballast water. The technologies and the potential risks are presented.

Conclusions

Despite the introduction of an approval procedure by IMO any reliable assessment of the real risks involved in the use of biocides is impossible, as the risk assessment approaches have still to be developed. On the regulatory level, the main focus in data requirements for the risk assessment is on a comprehensive testing of the toxic potential of the biocides proposed. Strategies for the identification and evaluation of the chemical resulting from the treatment of limnic, marine and brackish water are not fully developed. An integrating assessment of risks involved in the introduction of foreign organisms versus the toxic effects of the substances used or created during treatment is still missing.  相似文献   
99.
The effect of the spin-trap α-phenyl-N-t-butylnitrone (PBN) on the formation of fatty acid dimers induced by the anoxic microsomal metabolism of tetrachloromethane was investigated in vitro, in particular, with respect to cross-linking of arachidonic acid with a second one (C20–C20) and of arachidonic acid with docosahexaenoic acid (C20–C22). PBN exerted no effect on anaerobic tetrachloromethane metabolism but inhibited dimer formation, half-maximally at a concentration of 0.1 mmol L?1. Trichloromethyl octadecenoic acid was also found, but at levels 10-fold lower than the fatty acid dimers. The data suggest that the hepato-protective effect of PBN against tetrachloromethane-toxicity may be due to its ability to scavenge fatty acid radicals, resulting in stable, non-reactive entities, which do not undergo secondary reactions such as cross-linking. The data confirm and extend previous findings that crosslinking plays an important role in tetrachloromethane toxicity and similar cases of metabolic radical-induced toxicity.  相似文献   
100.
All known cosmic and geological conditions and laws of chemistry and thermodynamics allow that complex organic matter could have formed spontaneously on pristine planet Earth about 4,000 mya. Simple gasses and minerals on the surface and in oceans of the early Earth reacted and were eventually organized in supramolecular aggregates and enveloped cells that evolved into primitive forms of life. Chemical evolution, which preceded all species of extant organisms, is a fact. In this review, we have concentrated on experimental and theoretical research published over the last two decades, which has added a wealth of new details and helped to close gaps in our previous understanding of this multifaceted field. Recent exciting progress in the molecular and genetic analyses of existing life, in particular microorganisms of ancient origin, even supports the possibility that a cellular, self-reproducing common ancestor might be assembled and resurrected in anaerobic cultures at some time in the future. Charles Darwin did not, and indeed, could not, address and specify the earliest phases of life which preceded the Origin of Species. However, in a famous letter, he sketched “a warm little pond with all sorts of… (chemicals, in which) …a protein was chemically formed.” We try to trace the impact of his charming clear-sighted metaphor up to the present time.  相似文献   
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