Simulation and visualization of material flows in sanitation systems for streamlined sustainability assessment.

New and alternative sanitation systems are increasingly discussed and find their way into implementation. However, discussions on sanitation concepts often are held in a rather emotional way. Furthermore, not all the available sanitation concepts might be known to the decision maker. The work presented here attempts to contribute to a good discussion and decision making process by compiling available technologies, by defining easy-to-implement criteria for a sustainability assessment method and by integrating these results into a simulation tool which allows to visualize the related resource fluxes (e.g. those on nutrients, such as N, P and K) and to analyse different sanitation options with regard to their capital and operational costs and with regard to environmental impact criteria such as greenhouse gas emissions. Whilst the calculations are to be considered as being approximate in their nature (due to uncertainties or lack of suitable input data), this tool allows the planners, with sometimes little modelling experience, to consider the characteristics of sanitation systems. Whilst starting from earlier work, such as Eawag's Sanitation Compendium and work on material flow analysis, work described in this contribution merges resource flux modelling, easy-to-use simulation and visualization and methods of life cycle assessment and life cycle costing. The simulation tool is freely available on https://www.ifak.eu/en/products/sampsons.

Tactile event-related potentials in amyotrophic lateral sclerosis (ALS): Implications for brain-computer interface.

OBJECTIVE: We investigated neurophysiological brain responses elicited by a tactile event-related potential paradigm in a sample of ALS patients. Underlying cognitive processes and neurophysiological signatures for brain-computer interface (BCI) are addressed. METHODS: We stimulated the palm of the hand in a group of fourteen ALS patients and a control group of ten healthy participants and recorded electroencephalographic signals in eyes-closed condition. Target and non-target brain responses were analyzed and classified offline. Classification errors served as the basis for neurophysiological brain response sub-grouping. RESULTS: A combined behavioral and quantitative neurophysiological analysis of sub-grouped data showed neither significant between-group differences, nor significant correlations between classification performance and the ALS patients' clinical state. Taking sequential effects of stimuli presentation into account, analyses revealed mean classification errors of 19.4% and 24.3% in healthy participants and ALS patients respectively. CONCLUSIONS: Neurophysiological correlates of tactile stimuli presentation are not altered by ALS. Tactile event-related potentials can be used to monitor attention level and task performance in ALS and may constitute a viable basis for future BCIs. SIGNIFICANCE: Implications for brain-computer interface implementation of the proposed method for patients in critical conditions, such as the late stage of ALS and the (completely) locked-in state, are discussed.

Towards a more precise neurophysiological assessment of cognitive functions in patients with disorders of consciousness.

PURPOSE: To analyze the principles that guide inference of covert cognitive functions and consciousness in patients with extremely severe brain damage on the basis of neurophysiological test results. METHODS: (1) A quantitative analysis of a range of possible inferences based on neurophysiological findings in low- and non-responsive patients; (2) a logical analysis of the various possible orders of application of neurophysiological tests in such patients. RESULTS: Surprisingly, improvement of neurophysiological test qualities contributes to the improvement of diagnostic results less than some other factors, such as the structure of the patient population, the quality of the previous clinical diagnosis, and the variability of the methods used. CONCLUSIONS: A sequential decision procedure is suggested. Different test paradigms should be combined most effectively to arrive at a reliable evaluation of cognitive functions in this patient population.