Towards a benchmarking tool for minimizing wastewater utility greenhouse gas footprints

A benchmark simulation model, which includes a wastewater treatment plant (WWTP)-wide model and a rising main sewer model, is proposed for testing mitigation strategies to reduce the system's greenhouse gas (GHG) emissions. The sewer model was run to predict methane emissions, and its output was used as the WWTP model input. An activated sludge model for GHG (ASMG) was used to describe nitrous oxide (N(2)O) generation and release in activated sludge process. N(2)O production through both heterotrophic and autotrophic pathways was included. Other GHG emissions were estimated using empirical relationships. Different scenarios were evaluated comparing GHG emissions, effluent quality and energy consumption. Aeration control played a clear role in N(2)O emissions, through concentrations and distributions of dissolved oxygen (DO) along the length of the bioreactor. The average value of N(2)O emission under dynamic influent cannot be simulated by a steady-state model subjected to a similar influent quality, stressing the importance of dynamic simulation and control. As the GHG models have yet to be validated, these results carry a degree of uncertainty; however, they fulfilled the objective of this study, i.e. to demonstrate the potential of a dynamic system-wide modelling and benchmarking approach for balancing water quality, operational costs and GHG emissions.

Immunosuppressive treatment in refractory chronic inflammatory demyelinating polyradiculoneuropathy. A nationwide retrospective analysis

BACKGROUND AND PURPOSE

There are other options open to patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) who are non-responders to conventional treatment, including immunosuppressive and immunomodulatory agents (IA). The aim of this study was to assess whether the use of IA is able to increase the number of responders.

METHODS

Clinical and electrophysiological data of patients with refractory CIDP, followed at 10 Italian centres, were collected, and the clinical outcome (Rankin Scale) and drug side effects (SE) for the different therapies were analysed.

RESULTS

A total of 110 patients were included. These patients underwent 158 different therapeutic procedures with IA. Seventy-seven patients were treated with azathioprine, 18 rituximab, 13 cyclophosphamide, 12 mycophenolate mofetil, 12 cyclosporine, 12 methotrexate, 11 interferon-alpha and three interferon beta-1a. The percentage of patients who responded to azathioprine (27%) was comparable to the percentage of responders to other therapies, after the exclusion of interferon beta-1a that was not effective in any of the three patients treated. The percentage of SE ranges from 8% (methotrexate) to 50% (cyclosporine).

CONCLUSIONS

One-fourth of patients, refractory to conventional treatment, showed an improvement in their disability with IA. Methotrexate had the lowest SE; cyclosporine was associated with severe SE and often led to drug discontinuation.

[The role of the ASL of Brescia in the health and safety of immigrant workers]

According to available studies, migrant workers represent a vulnerable workers' category. For this reason, the Italian law on safety and health at work (art. 11, D.Lgs 81/08) points out the need for Public Administration initiatives devoted to migrant workers' health and safety at work. Local Public Health Department of Brescia for years now had a significant commitment in migrants' health. Thanks to the collaboration of occupational physicians and expert physicians on migration health, it was developed a multidimensional method to assess working risks taking into account also the fragile conditions of migrant workers, considering both personal and social characteristics and professional experience, in order to support companies in the planning of necessary actions to improve health and safety at work. The method was shared by both local industrial association and trade unions and then tested in some manufactures.

Rituximab in patients with chronic inflammatory demyelinating polyradiculoneuropathy: a report of 13 cases and review of the literature

BACKGROUND

A few case reports have shown controversial results of rituximab efficacy in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP).

OBJECTIVE

To analyse the efficacy of rituximab in a large CIDP cohort.

METHODS

A retrospective, observational and multicentre study on the use of rituximab in CIDP. 13 Italian CIDP patients were treated with rituximab after the partial or complete lack of efficacy of conventional therapies. Eight patients had co-occurring haematological diseases. Patients who improved by at least two points in standard clinical scales, or who reduced or discontinued the pre-rituximab therapies, were considered as responders.

RESULTS

Nine patients (seven with haematological diseases) responded to rituximab: six of them, who were non-responders to conventional therapies, improved clinically, and the other three maintained the improvement that they usually achieved with intravenous immunoglobulin or plasma exchange. Significantly associated with shorter disease duration, rituximab responses started after a median period of 2.0 months (range, 1-6) and lasted for a median period of 1 year (range, 1-5).

CONCLUSIONS

Rituximab seems to be a promising therapeutic choice when it targets both CIDP and co-occurring haematological diseases. Timely post-onset administration of rituximab seems to be associated with better responses.

Combining multimedia models with integrated urban water system models for micropollutants

Integrated urban water system (IUWS) modeling aims at assessing the quality of the surface water receiving the urban emissions through sewage treatment plants, combined sewer overflows (CSOs) and stormwater drainage systems. However, some micropollutants tend to appear in more than one environmental medium (air, water, sediment, soil, groundwater, etc.). In this work, a multimedia fate and transport model (MFTM) is "wrapped around" a dynamic IUWS model for organic micropollutants to enable integrated environmental assessment. The combined model was tested on a hypothetical catchment using two scenarios: on the one hand a reference scenario with a combined sewerage system and on the other hand a stormwater infiltration pond scenario, as an example of a sustainable urban drainage system (SUDS). A case for Bis(2-ethylhexyl) phthalate (DEHP) was simulated and resulted in reduced surface water concentrations for the latter scenario. However, the model also showed that this was at the expense of increased fluxes to air, groundwater and infiltration pond soil. The latter effects are generally not included in IUWS models, whereas MTFMs usually do not consider dynamic surface water concentrations,; hence the combined model approach provides a better basis for integrated environmental assessment of micropollutants' fate in urban environments.

Benchmark Simulation Model No 2: finalisation of plant layout and default control strategy

The COST/IWA Benchmark Simulation Model No 1 (BSM1) has been available for almost a decade. Its primary purpose has been to create a platform for control strategy benchmarking of activated sludge processes. The fact that the research work related to the benchmark simulation models has resulted in more than 300 publications worldwide demonstrates the interest in and need of such tools within the research community. Recent efforts within the IWA Task Group on "Benchmarking of control strategies for WWTPs" have focused on an extension of the benchmark simulation model. This extension aims at facilitating control strategy development and performance evaluation at a plant-wide level and, consequently, includes both pretreatment of wastewater as well as the processes describing sludge treatment. The motivation for the extension is the increasing interest and need to operate and control wastewater treatment systems not only at an individual process level but also on a plant-wide basis. To facilitate the changes, the evaluation period has been extended to one year. A prolonged evaluation period allows for long-term control strategies to be assessed and enables the use of control handles that cannot be evaluated in a realistic fashion in the one week BSM1 evaluation period. In this paper, the finalised plant layout is summarised and, as was done for BSM1, a default control strategy is proposed. A demonstration of how BSM2 can be used to evaluate control strategies is also given.

[Application of an integrated method for risk assessment of related work-stress in health care]

To assess the risk from exposure to occupational stress and burnout in health care workers (HCW), a cross-sectional study was planned to compare objective data that can represent potential job stressors in hospital wards and subjective symptoms reported by the workers. Medical doctors, nurses and ancillary workers of the Internal Medicine Wards of a large public hospital in Northern Italy were enrolled in the study. Three subjective questionnaires were administered: the Job Content Questionnaire, the State-Trait Anxiety Inventory, the Maslach Burnout Inventory. In addition, seven objective parameters were collected as average on the 3 months period prior to the study: a) working understaffed; b) number of patients/HCW on service; c) number of HCW on sick leave/on service; d) number of skipped days off after night shifts; e) number of sick leaves; f) number of deceased patients; g) number of accidents at work. A total group of 230 HCW were examined, employed in six different sub-units of the Medical wards. The female workers were 67.8% and the male workers 32.2%, the mean age was 37.4 years (SD 9.3) in the total group, 35.1 years (SD 7.9) in females and 42.3 years (SD 10.3) in males. The average scores of subjective and objective parameters resulted significantly higher in the same sub-units. The correlation analysis showed that the subjective questionnaires were highly inter-related. The multivariate analysis showed that the number of sick leave days was significantly related to the subjective questionnaires, and the subjective subscales of emotional exhaustion, job demand, decision latitude and STAIt were significantly related to some of the objective parameters. Therefore, the best approach to measure occupational stress is an integrated one, which involves the use of multiple subjective and objective assessment modalities.

Wastewater treatment modelling: dealing with uncertainties

This paper serves as a problem statement of the issues surrounding uncertainty in wastewater treatment modelling. The paper proposes a structure for identifying the sources of uncertainty introduced during each step of an engineering project concerned with model-based design or optimisation of a wastewater treatment system. It briefly references the methods currently used to evaluate prediction accuracy and uncertainty and discusses the relevance of uncertainty evaluations in model applications. The paper aims to raise awareness and initiate a comprehensive discussion among professionals on model prediction accuracy and uncertainty issues. It also aims to identify future research needs. Ultimately the goal of such a discussion would be to generate transparent and objective methods of explicitly evaluating the reliability of model results, before they are implemented in an engineering decision-making context.

Environmental and economic performance assessment of the integrated urban wastewater system

In order to comply with the Water Framework Directive's requirement to reveal the major pressures and impacts on the receiving water at river basin level, the merits of a methodology that combines substance flow analysis and mass balances were evaluated with the aid of a case study. The river basin analysis consisted of the analysis of all individual municipal sewer catchments constituting the basin on a yearly time scale, and included the description of the main sewers and waste water treatment plants and their performance in environmental and economical terms. A wide set of indicators was evaluated. Uncertainties and information gaps arising from the study are described. The choice of the geographic scale seems a key factor in the evaluation. The case study indicates that such an evaluation is of great value for decision-makers in the perspective of the Water Framework Directive implementation, to highlight situations of weak or strong performance and to pinpoint information gaps requiring further research in order to take more informed decisions, to identify the main pressures on the environment and to plan more cost-effective measures.

The homeobox gene Arx is a novel positive regulator of embryonic myogenesis

Skeletal muscle fibers form in overlapping, but distinct phases that depend on the generation of temporally different lineages of myogenic cells. During primary myogenesis (E10.5-E12.5 in the mouse), embryonic myoblasts fuse homotypically to generate primary fibers, whereas during later development (E14.5-E17.5), fetal myoblasts differentiate into secondary fibers. How these myogenic waves are regulated remains largely unknown. Studies have been hampered by the lack of markers which would distinguish embryonic from fetal myoblast populations. We show here that the homeobox gene Arx is strongly expressed in differentiating embryonic muscle, downstream of myogenic basic helix-loop-helix (bHLH) genes. Its expression progressively decreases during development. When overexpressed in the C2C12 myogenic cell line, Arx enhances differentiation. Accordingly, it stimulates the transcriptional activity from the Myogenin promoter and from multimerized E-boxes when co-expressed with MyoD and Mef2C in CH310T1/2. Furthermore, Arx co-immunoprecipitates with Mef2C, suggesting that it participates in the transcriptional regulatory network acting in embryonic muscle. Finally, embryonic myoblasts isolated from Arx-deficient embryos show a delayed differentiation in vivo together with an enhanced clonogenic capacity in vitro. We propose here that Arx acts as a novel positive regulator of embryonic myogenesis by synergizing with Mef2C and MyoD and by establishing an activating loop with Myogenin.

[Occupational exposure to manganese in ferroalloy industry: neurobehavioral effects in a workers' cohort]

Our Institute has been following for 20 years a group of workers of a ferroalloy industry in order to evaluate neurobehavioral effects due to manganese exposure. Five years after the last study we have planned another one, to evaluate differences in neuromotor e cognitive functions between exposed and controls and to perform a longitudinal evaluation of the results. Environmental and biological sampling were collected, liver and kidney functionality, haemochrome, iron metabolism and sieric prolactine were evaluated. Several tests were administered: postural evaluation, tremor, four tests of the SPES battery, Pursuing Aiming, five tests of the Luria Nebraska Motor Battery, Raven Progressive Matrices, Trail Making Test, Mood Scale, Brief Symptoms Inventory, neuropsychological symptoms questionnaire. Personal habits and working, living and clinical histories were collected. We evaluated 43 exposed workers and 40 controls. Exposure indicators resulted all significantly higher in exposed workers. Neuropsychological examination showed differences in Raven Progressive Matrices and Pursuit Aiming, higher tremor values and differences in postural evaluation between exposed and controls.

Neurological and neuropsychological features in Parkinsonian patients exposed to neurotoxic metals

BACKGROUND

Environmental exposure to heavy metals and especially manganese (Mn) took place in Valcamonica, Italy, where a high prevalence of Parkinsonism was observed (age and sex standardized 407/100,000; 95% CI: 393.87-420.12), and the Standardized Morbidity Ratios was associated with environmental Mn levels.

METHODS

A cross sectional study compared Parkinsonian patients residents in Valcamonica with patients from Brescia, Italy. Age- and sex-matched healthy individuals were recruited as controls. The protocol included information on clinical, occupational, residential history and life habits, neuro-psychological testing, and assessment of genetic polymorphism.

RESULTS

The target group included 65 patients and 52 controls from Valcamonica, 28 patients and 14 controls from Brescia. Age at onset of the disease was lower in women from both areas. After adjusting for age and age at onset, patients from Valcamonica showed more severe motor impairment at the UPDRS scale, higher damage of cognitive and motor functions at MMSE, Token and Trial Making tests. Genetic variables showed a different allelic distribution of DRD4 gene between cases and controls, outside Valcamonica, where a less frequent familiarity for parkinsonism was reported.

CONCLUSIONS

Parkinsonian patients with previous exposure to metals showed a more severe neuropsychological phenotype, without detectable contribution from genetic factors.

[Metals and oxidative stress in Parkinson's disease from industrial areas with exposition to environmental toxins or metal pollution]

BACKGROUND

Parkinson's disease (PD) is characterized by a progressive degeneration of the nigrostriatal dopaminergic pathway resulting in movement disorders. PD is a complex disease, in which and environmental factors, as exposure to toxins or metals coul be involved.

OBJECTIVE

To assess if serum metals (Cu, Fe, Zn), biological variables of their metabolism, total peroxides and antioxidants were abnormal in PD, in relation to environmental exposure.

METHODS

We compared levels of serum copper, iron, zinc, ceruloplasmin and transferrin, peroxides, antioxidants (TRAP) in 65 PD patients coming from an Industrial zone highly exposed to metal pollution (Valcamonica) with measures from 28 PD patients from no metal pollution areas of the province of Brescia and 52 healthy controls coming from Valcamonica and 24 from the province of Brescia.

RESULTS

PD patients had higher serum concentration of zinc than controls. Only in PD patients coming from Valcamonica levels of Cu were higher than in subjects coming from the province of Brescia. Moreover, In patients with PD levels of sieric Cu significantly correlated with score of the Unified Parkinson's Disease Rating Scale (UDPRS).

CONCLUSIONS

Zinc seems to be higher in PD independently from the exposition to metal pollution. Perturbation of copper metabolism in PD seems to be related to exposition to environmental toxins or metal pollution and coul be involved in the progression of the disease itself.

Prevalence and characteristics of peripheral neuropathy in hepatitis C virus population

OBJECTIVE

To assess the prevalence of peripheral neuropathy (PN) and its correlation with cryoglobulinemia (CG) in an unselected, untreated referral hepatitis C virus (HCV) population.

PATIENTS AND METHODS

Two hundred and thirty four patients (120 women and 114 men) with untreated HCV infection were consecutively enrolled by seven Italian centres. Clinical neuropathy was diagnosed when symptoms and signs of peripheral sensory or motor involvement were present. Median, ulnar, peroneal, and sural nerves were explored in all patients and distal symmetric polyneuropathy was diagnosed when all explored nerves or both lower limb nerves were affected. Mononeuropathy and mononeuropathy multiplex were diagnosed when one nerve or two non-contiguous nerves with asymmetrical distribution were affected. Screening for CG was done in 191 unselected patients.

RESULTS

Clinical signs of PN were observed in 25 of the 234 patients (10.6%). Electrophysiological PN was found in 36 (15.3%). CG was present in 56/191 patients (29.3%). The prevalence of CG increased significantly with age (p<0.001) and disease duration (p<0.05). PN was present in 12/56 (21%) patients with CG and 18/135 (13%) without CG (p=NS). PN increased significantly with age (p<0.001) and logistic regression analysis confirmed age as the only independent predictor of PN (OR 1.10 for each year; 95% CI 1.04 to 1.15; p<0.001).

CONCLUSIONS

Electrophysiological examination detected subclinical neuropathy in 11 patients (4.7%). Statistical analysis showed that CG was not a risk factor for PN whereas PN prevalence increased significantly with age.

Distributed virtual experiments in water quality management

Since the complexity of virtual experiments (VEs) and their underlying models is constantly increasing, computational performance of monolithic software solutions is rapidly becoming insufficient. Examples of VEs are probabilistic design, model calibration, optimal experimental design and scenario analysis. In order to tackle this computational bottleneck, a framework for the distributed execution of VEs on a potentially heterogeneous pool of work nodes has been implemented. This framework was named WDVE (WEST distributed virtual experimentation) and is built on top of technologies such as C++, XML and SOAP. It was designed for stability, expandability, performance, platform-independence and ease of use. Complex VEs are most often composed of mutually independent sub-experiments, which can be run concurrently. With WDVE, a complex VE that is executed on a so-called Master machine will therefore attempt to execute its sub-experiments on Slave machines that have previously registered with the Master. The process of submitting requests for the execution of sub-experiments is transparent and involves the transfer of a description of the experiment to be executed, and the resources that are needed for the execution (i.e., model and input data). WDVE is in many ways similar to the Grid Computing paradigm, which is currently receiving widespread attention. However, WDVE is more geared towards application within the scope of water quality management.

Assessment of WWTP design and upgrade options: balancing costs and risks of standards' exceedance

Numerical models can be used to evaluate design and upgrade scenarios of urban wastewater systems on the basis of their ecological consequences. The objective of this paper is to illustrate a systematic procedure of system design/upgrade. This procedure consists of the following steps: (1) data collection and data reconstruction; (2) model building and calibration; (3) evaluation of scenarios; (4) uncertainty assessment. In contrast to conventional practice, this approach allows to choose the most appropriate trade-off between cost of measures and risk of non-compliance with regulatory limits. An example of its application dealing with the assessment of WWTP design and upgrade options is provided. Results show that by reducing the tank volumes compared to conventional design procedures, costs can be reduced sensibly while the risk of not meeting legislative requirements are only slightly increased.

Estimating costs and benefits of advanced control for wastewater treatment plants--the MAgIC methodology

This paper discusses a methodology to estimate the costs and benefits of advanced control for wastewater treatment plants. The methodology has been applied to four wastewater treatment plants, representing four standard types of plants built in Flanders, Belgium. The paper outlines the methodology and illustrated results from one of the four design cases. General results are shown and contrasted with full-scale experience. The methodology appears to give realistic results and will be used for further refinement of default control algorithms for certain types of plants. A preliminary analysis indicates that on-line control can become cost-effective for plant sizes above 50,000 population equivalents.

Benchmarking of WWTP design by assessing costs, effluent quality and process variability

Process choice and dimensioning of WWTPs is a particularly sensitive step to cost-efficiently comply with regulatory standards. This step accounts only for a small fraction of the upfront costs, but it can lead to substantial savings. This paper illustrates the results of a systematic methodology to evaluate system design/upgrade options. In contrast to conventional practice, this approach allows the choice between the most appropriate trade-off between cost of measures and effluent quality, and to assess the reliability of a process layout. It is therefore a flexible instrument to cope with the flexibility and complexity of integrated water management regulations. Results show good agreement of the simulations with extensiv benchmarking studies on actual plants. For that reason, the suggested methodology can provide valuable support also to such practices.

Systems analysis of urban wastewater systems--two systematic approaches to analyse a complex system

This work was aimed at performing an analysis of the integrated urban wastewater system (catchment area, sewer, WWTP, receiving water). It focused on analysing the substance fluxes going through the system to identify critical pathways of pollution, as well as assessing the effectiveness of energy consumption and operational/capital costs. Two different approaches were adopted in the study to analyse urban wastewater systems of diverse characteristics. In the first approach a wide ranged analysis of a system at river basin scale is applied. The Nete river basin in Belgium, a tributary of the Schelde, was analysed through the 29 sewer catchments constituting the basin. In the second approach a more detailed methodology was developed to separately analyse two urban wastewater systems situated within the Ruhr basin (Germany) on a river stretch scale. The paper mainly focuses on the description of the method applied. Only the most important results are presented. The main outcomes of these studies are: the identification of stressors on the receiving water bodies, an extensive benchmarking of wastewater systems, and the evidence of the scale dependency of results in such studies.

Continuity-based interfacing of models for wastewater systems described by Petersen matrices

In this paper the Petersen and composition matrices that modellers are now familiar with are used as a basis to construct interfacing models between subsystems considered in wastewater treatment. Starting from continuity considerations and a set of transformation reactions between components used in the two models of the subsystems to be interfaced, a set of linear algebraic equations needs to be solved. The theoretical development is illustrated using a simplified integrated model of an activated sludge system coupled to an anaerobic digester. Continuity-guaranteed interfacing of subsystems will facilitate optimization studies of the within-the-fence process units of a wastewater treatment plant or of the integrated urban wastewater system.

[Neurobehavioral tests in occupational medicine: diagnosis and prevention]

Modern neurobehavioral methods are used in the assessment of the early effects due to exposure to neurotoxic agents in working and general environment. This paper describes the history and evolution of neurobehavioral methods and their contribution for research on the effects due to the exposure to neurotoxic substances. Moreover, the paper describes the different fields of application of neurobehavioral tests: experimental, epidemiological and follow-up studies, health surveillance, clinical diagnosis, definition of job fitness and risk assessment for the definition of threshold limit values.