1,612 research outputs found

    Methods for the evaluation of waste treatment processes

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    Decision makers for waste management are confronted with the problem of selecting the most economic, environmental, and socially acceptable waste treatment process. This paper elucidates evaluation methods for waste treatment processes for the comparison of ecological and economic aspects such as material flow analysis, statistical entropy analysis, energetic and exergetic assessment, cumulative energy demand, and life cycle assessment. The work is based on the VDI guideline 3925. A comparison of two thermal waste treatment plants with different process designs and energy recovery systems was performed with the described evaluation methods. The results are mainly influenced by the type of energy recovery, where the waste-to-energy plant providing district heat and process steam emerged to be beneficial in most aspects. Material recovery options from waste incineration were evaluated according to sustainability targets, such as saving of resources and environmental protection

    Methods for the Evaluation of Waste Treatment Processes

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    Decision makers for waste management are confronted with the problem of selecting the most economic, environmental, and socially acceptable waste treatment process. This paper elucidates evaluation methods for waste treatment processes for the comparison of ecological and economic aspects such as material flow analysis, statistical entropy analysis, energetic and exergetic assessment, cumulative energy demand, and life cycle assessment. The work is based on the VDI guideline 3925. A comparison of two thermal waste treatment plants with different process designs and energy recovery systems was performed with the described evaluation methods. The results are mainly influenced by the type of energy recovery, where the waste-to-energy plant providing district heat and process steam emerged to be beneficial in most aspects. Material recovery options from waste incineration were evaluated according to sustainability targets, such as saving of resources and environmental protection

    Assessment of the Synergy between Recycling and Thermal Treatments in Municipal Solid Waste Management in Europe

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    In 2018, the production of Municipal SolidWaste (MSW) in EU-28 reached 250.6 Mt, with the adoption of dierent management strategies, involving recycling (48 wt %), incineration and thermal valorization (29 wt %) and landfilling (23 wt %). This work was based on the analysis of the baseline situation of MSW management in EU-28 in 2018, considering its progress in 2008–2018, and discussed the possible improvement perspectives based on a framework involving incineration and recycling as the only possible alternatives, specifically evaluating the capability of already-existing incineration plants to fulfill the EU needs in the proposed framework. The results of the assessment showed two main crucial issues that could play a pivotal role in the achievement of Circular Economy action plan targets: the need to increase the recycling quotas for specific MSW fractions through the separate collection, and therefore the improvement of definite treatment process chains; the optimization of the recovery of secondary raw materials from incineration bottom ash, involving the recycling of ferrous and nonferrous metals and the mineral fraction. Both issues need to find an extensive application across all member states to decrease the actual dierences in the adoption of sustainable MSW management options

    A Novel Dry Treatment for Municipal Solid Waste Incineration Bottom Ash for the Reduction of Salts and Potential Toxic Elements

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    The main obstacle to bottom ash (BA) being used as a recycling aggregate is the content of salts and potential toxic elements (PTEs), concentrated in a layer that coats BA particles. This work presents a dry treatment for the removal of salts and PTEs from BA particles. Two pilot-scale abrasion units (with/without the removal of the fine particles) were fed with different BA samples. The performance of the abrasion tests was assessed through the analyses of particle size and moisture, and that of the column leaching tests at solid-to-liquid ratios between 0.3 and 4. The results were: the particle-size distribution of the treated materials was homogeneous (25 wt % had dimensions <6.3 mm) and their moisture halved, as well as the electrical conductivity of the leachates. A significant decrease was observed in the leachates of the treated BA for sulphates (44%), chlorides (26%), and PTEs (53% Cr, 60% Cu and 8% Mo). The statistical analysis revealed good correlations between chloride and sulphate concentrations in the leachates with Ba, Cu, Mo, and Sr, illustrating the consistent behavior of the major and minor components of the layer surrounding BA particles. In conclusion, the tested process could be considered as promising for the improvement of BA valorization

    Does the relative importance of the OxCAP-MH's capability items differ according to mental ill-health experience?

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    Background: Some capability dimensions may be more important than others in determining someone’s well-being, and these preferences might be dependent on ill-health experience. This study aimed to explore the relative preference weights of the 16 items of the German language version of the OxCAP-MH (Oxford Capability questionnaire-Mental Health) capability instrument and their differences across cohorts with alternative levels of mental ill-health experience. Methods: A Best–Worst-Scaling (BWS) survey was conducted in Austria among 1) psychiatric patients (direct mental ill-health experience), 2) (mental) healthcare experts (indirect mental ill-health experience), and 3) primary care patients with no mental ill-health experience. Relative importance scores for each item of the German OxCAP-MH instrument were calculated using Hierarchical Bayes estimation. Rank analysis and multivariable linear regression analysis with robust standard errors were used to explore the relative importance of the OxCAP-MH items across the three cohorts. Results: The study included 158 participants with complete cases and acceptable fit statistic. The relative importance scores for the full cohort ranged from 0.76 to 15.72. Findings of the BWS experiment indicated that the items Self-determination and Limitation in daily activities were regarded as the most important for all three cohorts. Freedom of expression was rated significantly less important by psychiatric patients than by the other two cohorts, while Having suitable accommodation appeared significantly less important by the expert cohort. There were no further significant differences in the relative preference weights of OxCAP-MH items between the cohorts or according to gender. Conclusions: Our study indicates significant between-item but limited mental ill-health related heterogeneity in the relative preference weights of the different capability items within the OxCAP-MH. The findings support the future development of preference-based value sets elicited from the general population for comparative economic evaluation purposes

    Legal situation and current practice of waste incineration bottom ash utilisation in Europe

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    Almost 500 municipal solid waste incineration plants in the EU, Norway, and Switzerland generate about 17.6 Mt/a of incinerator bottom ash (IBA). IBA contains minerals and metals. Metals are mostly separated and sold to the scrap market and minerals are either disposed of in landfills or utilised in the construction sector. Since there is no uniform regulation for IBA utilisation at EU level, countries developed own rules with varying requirements for utilisation. As a result from a cooperation network between European experts an up-to-date overview of documents regulating IBA utilisation is presented. Furthermore, this work highlights the different requirements that have to be considered. Overall, 51 different parameters for the total content and 36 different parameters for the emission by leaching are defined. An analysis of the defined parameter reveals that leaching parameters are significantly more to be considered compared to total content parameters. In order to assess the leaching behaviour nine different leaching tests, including batch tests, up-flow percolation tests and one diffusion test (monolithic materials) are in place. A further discussion of leaching parameters showed that certain countries took over limit values initially defined for landfills for inert waste and adopted them for IBA utilisation. The overall utilisation rate of IBA in construction works is approximately 54 wt.%. It is revealed that the rate of utilisation does not necessarily depend on how well regulated IBA utilisation is, but rather seems to be a result of political commitment for IBA recycling and economically interesting circumstances

    QRS micro-fragmentation as a mortality predictor.

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    AIMS Fragmented QRS complex with visible notching on standard 12-lead electrocardiogram (ECG) is understood to represent depolarization abnormalities and to signify risk of cardiac events. Depolarization abnormalities with similar prognostic implications likely exist beyond visual recognition but no technology is presently suitable for quantification of such invisible ECG abnormalities. We present such a technology. METHODS AND RESULTS A signal processing method projects all ECG leads of the QRS complex into optimized three perpendicular dimensions, reconstructs the ECG back from this three-dimensional projection, and quantifies the difference (QRS 'micro'-fragmentation, QRS-μf) between the original and reconstructed signals. QRS 'micro'-fragmentation was assessed in three different populations: cardiac patients with automatic implantable cardioverter-defibrillators, cardiac patients with severe abnormalities, and general public. The predictive value of QRS-μf for mortality was investigated both univariably and in multivariable comparisons with other risk factors including visible QRS 'macro'-fragmentation, QRS-Mf. The analysis was made in a total of 7779 subjects of whom 504 have not survived the first 5 years of follow-up. In all three populations, QRS-μf was strongly predictive of survival (P < 0.001 univariably, and P < 0.001 to P = 0.024 in multivariable regression analyses). A similar strong association with outcome was found when dichotomizing QRS-μf prospectively at 3.5%. When QRS-μf was used in multivariable analyses, QRS-Mf and QRS duration lost their predictive value. CONCLUSION In three populations with different clinical characteristics, QRS-μf was a powerful mortality risk factor independent of several previously established risk indices. Electrophysiologic abnormalities that contribute to increased QRS-μf values are likely responsible for the predictive power of visible QRS-Mf. KEY QUESTION KEY FINDING TAKE-HOME MESSAGE QRS-μf is a strong predictor of worsened survival. It can be assessed in standard short-term 12-lead electrocardiograms

    PEtab -- interoperable specification of parameter estimation problems in systems biology

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    Reproducibility and reusability of the results of data-based modeling studies are essential. Yet, there has been -- so far -- no broadly supported format for the specification of parameter estimation problems in systems biology. Here, we introduce PEtab, a format which facilitates the specification of parameter estimation problems using Systems Biology Markup Language (SBML) models and a set of tab-separated value files describing the observation model and experimental data as well as parameters to be estimated. We already implemented PEtab support into eight well-established model simulation and parameter estimation toolboxes with hundreds of users in total. We provide a Python library for validation and modification of a PEtab problem and currently 20 example parameter estimation problems based on recent studies. Specifications of PEtab, the PEtab Python library, as well as links to examples, and all supporting software tools are available at https://github.com/PEtab-dev/PEtab, a snapshot is available at https://doi.org/10.5281/zenodo.3732958. All original content is available under permissive licenses

    Translation on demand by a simple RNA-based thermosensor

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    Structured RNA regions are important gene control elements in prokaryotes and eukaryotes. Here, we show that the mRNA of a cyanobacterial heat shock gene contains a built-in thermosensor critical for photosynthetic activity under stress conditions. The exceptionally short 5′-untranslated region is comprised of a single hairpin with an internal asymmetric loop. It inhibits translation of the Synechocystis hsp17 transcript at normal growth conditions, permits translation initiation under stress conditions and shuts down Hsp17 production in the recovery phase. Point mutations that stabilized or destabilized the RNA structure deregulated reporter gene expression in vivo and ribosome binding in vitro. Introduction of such point mutations into the Synechocystis genome produced severe phenotypic defects. Reversible formation of the open and closed structure was beneficial for viability, integrity of the photosystem and oxygen evolution. Continuous production of Hsp17 was detrimental when the stress declined indicating that shutting-off heat shock protein production is an important, previously unrecognized function of RNA thermometers. We discovered a simple biosensor that strictly adjusts the cellular level of a molecular chaperone to the physiological need
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