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921.

Purpose

The purpose of the study is the enhancement of criticality assessments for resources in order to address function specific factors like dissipation, recycling, bio-activity and toxicity. The developed methodology is applied to platinum-containing cytostatic drugs and automotive catalytic converters.

Methods

The study is methodically based on an analysis of resource specific factors like exploration rates, reserves-to-production ratio and regional distribution of exploration areas as well as on the investigation of product/functional depending factors like recycling rates, dissipation rates, bio-diversity and toxicity. Taking into account that economic and ecological risks may occur at any stage of the supply, consumption and dissipation processes, the whole life cycles of the two analyzed products (cytostatic drugs and automotive catalytic converters) are considered. As an approach to reduce potential economic and ecological risks the study is especially focused on recycling strategies.

Background

In order to get a better understanding of platinum as an essential resource for the development of our society the history and the cultural impact of the term "resource" are introduced.

Results & Discussion

The availability of platinum is crucial for several products of our modern society. Areas of application are e.g. jewellery, automotive catalytic converters, investments (coins, bars), computers, mobile devices, fertilizers and cytostatic drugs. Economic risks are caused by limited sources and dynamic demand of new application areas like fuel cells and drugs. Platinum-containing drugs are used for the treatment of several kinds of cancer such as testicular, breast, colon and prostate. Currently the pharmaceutical industry requires 6,9 tons per year (3 percent of the total demand of platinum). Due to the improvement of medical standards and the ageing society, especially in developing countries, the demand of platinum-containing drugs will rise significantly. The dissipation of toxic soluble salts and the lack of advanced waste-water treatment and recycling systems is a problem of the usage of platinum-containing drugs. Compared with cytostatic drugs (14.6 kg/a for Germany) the dissipation of platinum particles of mobile catalytic converters is much higher (5-20 tons/a only in North America, Europe and Japan; 184,2 kg/a in Germany). On the other hand the emission of platinum nano-particles of automotive catalytic converters seems less critical. Furthermore advanced recycling technologies are already available for them.

Conclusions

The evaluation of resources has to consider resource specific and functional depending factors. In order to reduce economic and ecological risks of the dissipation of platinum salts in cytostatic drugs three principle options can be identified: the development of ecologically compatible and cost-effective substitutes, efficient recycling systems and future-oriented sanitary-systems as well as waste-water treatment facilities, which are able to separate platinum salts. Concerning the dissipation of platinum particles of mobile converters relevant research questions are the identification of adequate substitutes as well as the extension of recycling capacities.

Recommendations and perspectives

The study demonstrates a research gap concerning substitutes for automotive catalytic converters as well as for platinum-containing cytostatic drugs. The development and implementation of recycling concepts, technologies and capacities to reuse platinum as a secondary resource is an essential issue. As a consequence the economic and ecological risks can be reduced by increasing the resource efficiency. Special research has to be done concerning the development of future-oriented sanitary-systems and waste-water treatment facilities in order to separate platinum in waste water. Furthermore, if the future demand of new products like fuel cells is considered, a resource conflict concerning the potential functional applications will be evident. In order to address these challenges the criticality assessment has to be enhanced by ethic and social factors.  相似文献   
922.
The present paper outlines potential shortcomings of analyzing events in high hazard systems. We argue that the efficiency of organizational learning within high hazard systems is at least partially undermined by the subjective theories of organizing held by their members. These subjective theories basically reflect an “engineering” understanding of “how a system and its components perform”, and are assumed to involve (social-) psychological blind spots when applied to the analysis of events. More specifically, we argue that they neglect individual motives and goals that critically drive work performance and social interactions in high hazard systems. First, we focus on the process of identifying the causes of failed organizing within the course of an event analysis. Our analysis reveals a mismatch between the basic functional assumptions of the event analyst on the motives of social actors involved in an event and on the other hand, the perspective held by the social actors themselves. Second, we discuss the process of correcting failed social system performance after events. Thereby we draw on blind spots that emerge from the direct application of technical safety principles (i.e., standardization and redundancy) to the organization of social systems. Finally, we propose some future research strategies for developing event analysis methods which are aimed at improving an organization’s learning potential.  相似文献   
923.
924.

Objective

Omphalocele is known to be associated with genetic anomalies like trisomy 13, 18 and Beckwith–Wiedemann syndrome, but not with Turner syndrome (TS). Our aim was to assess the incidence of omphalocele in fetuses with TS, the phenotype of this association with other anomalies, their karyotype, and the fetal outcomes.

Method

Retrospective multicenter study of fetuses with confirmed diagnosis of TS. Data were extracted from a detailed questionnaire sent to specialists in prenatal ultrasound.

Results

680 fetuses with TS were included in this analysis. Incidence of small omphalocele in fetuses diagnosed ≥12 weeks was 3.1%. Including fetuses diagnosed before 12 weeks, it was 5.1%. 97.1% (34/35) of the affected fetuses had one or more associated anomalies including increased nuchal translucency (≥3 mm) and/or cystic hygroma (94.3%), hydrops/skin edema (71.1%), and cardiac anomalies (40%). The karyotype was 45,X in all fetuses. Fetal outcomes were poor with only 1 fetus born alive.

Conclusion

TS with 45,X karyotype but not with X chromosome variants is associated with small omphalocele. Most of these fetuses have associated anomalies and a poor prognosis. Our data suggest an association of TS with omphalocele, which is evident from the first trimester.  相似文献   
925.
In the framework of EU project "Utilising innovative kiln technology to recycle waste into synthetic aggregate" (BRST-CT98-5234), the leaching behaviour of synthetic aggregates has been studied to assess its environmental compatibility in the various stages of its use. Since the conditions are very different for the different uses, the assessment calls for a variety of different leaching conditions. The pH dependence test is used to cover important differences in pH environment to which the materials are exposed to as well as for an assessment of the buffering capacity of the material. Synthetic aggregate features a low buffer capacity, which makes it sensitive to externally imposed pH conditions. Utilisation and storage exposed to acidic conditions needs to be avoided. The results of the pH dependence test and column leaching test are mutually consistent. The CEN TC 154 method appears to provide systematically low values due to the arbitrary selection of test conditions. Synthetic aggregate studied to date will not adversely affect the concrete in its service life. The main issue for aggregate use is the recycling and the "end of life" condition, when the material becomes construction debris. Not metals, but oxyanions, such as Cr VI and Mo are most relevant under these conditions. A concise test has been applied to assess crucial aspects of leaching for different production mixes.  相似文献   
926.
Plant biomass and plant abundance can be controlled by aboveground and belowground natural enemies. However, little is known about how the aboveground and belowground enemy effects may add up. We exposed 15 plant species to aboveground polyphagous insect herbivores and feedback effects from the soil community alone, as well as in combination. We envisaged three possibilities: additive, synergistic, or antagonistic effects of the aboveground and belowground enemies on plant biomass. In our analysis, we included native and phylogenetically related range-expanding exotic plant species, because exotic plants on average are less sensitive to aboveground herbivores and soil feedback than related natives. Thus, we examined if lower sensitivity of exotic plant species to enemies also alters aboveground-belowground interactions. In a greenhouse experiment, we exposed six exotic and nine native plant species to feedback from their own soil communities, aboveground herbivory by polyphagous insects, or a combination of soil feedback and aboveground insects and compared shoot and root biomass to control plants without aboveground and belowground enemies. We observed that for both native and range-expanding exotic plant species effects of insect herbivory aboveground and soil feedback added up linearly, instead of enforcing or counteracting each other. However, there was no correlation between the strength of aboveground herbivory and soil feedback. We conclude that effects of polyphagous aboveground herbivorous insects and soil feedback add up both in the case of native and related range-expanding exotic plant species, but that aboveground herbivory effects may not necessarily predict the strengths of soil feedback effects.  相似文献   
927.
Organic contaminants [polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenylethers (PBDEs), nonylphenols], organotin compounds and trace metals (cadmium, chromium, mercury and zinc) were determined in flounder (Platichthys flesus) liver and sediment from the Amsterdam harbour (North Sea Canal) and Rotterdam harbour (Euromonding) and off the Dutch coast between the Amsterdam and Rotterdam harbour mouths in order to assess the level of contamination in these harbours and to study contamination gradients.  相似文献   
928.
Journal of Material Cycles and Waste Management - This work is aimed at exploring the recovery of heavy metals from the fine fraction of solid waste incineration bottom ash. For this study,...  相似文献   
929.
Journal of Material Cycles and Waste Management - In this study, the amount of medical waste generated in a high-populated city in Turkey between January 2018 and August 2021 was evaluated, and the...  相似文献   
930.
Conservation translocation is a common method for species recovery, for which one increasingly frequent objective is restoring lost ecological functions to promote ecosystem recovery. However, few conservation translocation programs explicitly state or monitor function as an objective, limiting the ability to test assumptions, learn from past efforts, and improve management. We evaluated whether translocations of hihi (Notiomystis cincta), a threatened New Zealand passerine, achieved their implicit objective of restoring lost pollination function. Through a pollinator-exclusion experiment, we quantified, with log response ratios (lnR), the effects of birds on fruit set and seed quality in hangehange (Geniostoma ligustrifolium), a native flowering shrub. We isolated the contributions of hihi by making comparisons across sites with and without hihi. Birds improved fruit set more at sites without hihi (lnR = 1.27) than sites with hihi (lnR = 0.50), suggesting other avian pollinators compensated for and even exceeded hihi contributions to fruit set. Although birds improved seed germination only at hihi sites (lnR = 0.22–0.41), plants at sites without hihi had germination rates similar to hihi sites because they produced 26% more filled seeds, regardless of pollination condition. Therefore, although our results showed hihi improved seed quality, they also highlighted the complexity of ecological functions. When an important species is lost, ecosystems may be able to achieve similar function through different means. Our results underscore the importance of stating and monitoring the ecological benefits of conservation translocations when functional restoration is a motivation to ensure these programs are achieving their objectives.  相似文献   
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