scholarly journals Data filtering methods for SARS-CoV-2 wastewater surveillance

2021 ◽  
Author(s):  
Rezgar Arabzadeh ◽  
Daniel Martin Grünbacher ◽  
Heribert Insam ◽  
Norbert Kreuzinger ◽  
Rudolf Markt ◽  
...  
Keyword(s):  
Performance Metrics ◽  
Wastewater Treatment Plants ◽  
Additive Model ◽  
Optimization Procedure ◽  
Data Filtering ◽  
Sewer System ◽  
Infection Dynamics ◽  
Virus Excretion ◽  
Random Fluctuations ◽  
Positive Effect

Abstract In the case of SARS-CoV-2 pandemic management, wastewater-based epidemiology aims to derive information on the infection dynamics by monitoring virus concentrations in the wastewater. However, due to the intrinsic random fluctuations of the viral signal in wastewater caused by several influencing factors that cannot be determined in detail (e.g. dilutions; number of people discharging; variations in virus excretion; water consumption per day; transport and fate processes in sewer system), the subsequent prevalence analysis may result in misleading conclusions. It is thus helpful to apply data filtering techniques to reduce the noise in the signal. In this paper we investigate 13 smoothing algorithms applied to the virus signals monitored in four wastewater treatment plants in Austria. The parameters of the algorithms have been defined by an optimization procedure aiming for performance metrics. The results are further investigated by means of a cluster analysis. While all algorithms are in principle applicable, SPLINE, Generalized Additive Model and Friedman's Super Smoother are recognized as superior methods in this context (with the latter two having a tendency to over-smoothing). A first analysis of the resulting datasets indicates the positive effect of filtering to the correlation of the viral signal to monitored incidence values.

Monitoring micropollutants in the Swist river basin

2016 ◽  
Vol 74 (10) ◽  
pp. 2280-2296 ◽  
Author(s):  
Ekkehard Christoffels ◽  
Andrea Brunsch ◽  
Jens Wunderlich-Pfeiffer ◽  
Franz Michael Mertens
Keyword(s):  
River Basin ◽  
Urban Areas ◽  
Flame Retardants ◽  
Wastewater Treatment Plants ◽  
Beta Blockers ◽  
Management Strategies ◽  
Sewer System ◽  
Receiving River ◽  
Western Germany ◽  
Industrial Compounds

Micropollutant pathways were studied for the Swist river basin (Western Germany). The aim was to verify the effectiveness of a monitoring approach to detect micropollutants entering the river. In a separate sewer system, water was frequently found to be contaminated with micropollutants. Improper connections of sewage canals to the stormwater network seemed to be the cause of pollution. Wastewater treatment plants (WWTPs) exerted the largest influence on micropollutants for the receiving river. During a flu outbreak, antibiotics in the Swist stemming from WWTPs increased remarkably. Elevated levels of pharmaceuticals were measured in discharges from a combined sewer overflow (CSO). The study showed that the pharmaceutical load of a CSO was significantly reduced by advanced treatment with a retention soil filter. Painkillers, an anticonvulsant and beta blockers were the most often detected pharmaceuticals in the sewage of urban areas. Herbicides, flame retardants and industrial compounds were also observed frequently. On cropland, Chloridazon and Terbuthylazine compounds were often found in landscape runoff. Fungicides and insecticides were the most frequent positive findings in runoff from orchards. The paper shows that a coherent approach to collecting valid information regarding micropollutants and to addressing relevant pathways as a basis for appropriate management strategies could be established.

Biodegradation of PAH and DEHP micro-pollutants in mesophilic and thermophilic anaerobic sewage sludge digestion

2006 ◽  
Vol 53 (8) ◽  
pp. 99-107 ◽  
Author(s):  
T. Benabdallah El-Hadj ◽  
J. Dosta ◽  
J. Mata-Álvarez
Keyword(s):  
Anaerobic Digestion ◽  
Wastewater Treatment Plants ◽  
Economic Cost ◽  
Process Efficiency ◽  
Sludge Digestion ◽  
Thermophilic Conditions ◽  
Polycyclic Aromatic ◽  
Positive Effect ◽  
Process Product ◽  
Micro Pollutants

Anaerobic digestion for the treatment of sludge in wastewater treatment plants has been reported to produce a low organic loaded effluent with an acceptable economic cost. But in the last years, new regulations and the increasing sludge production invite us to find an alternative and/or to improve the process efficiency. Moreover, the use of the effluent as fertilizer in agriculture imposes more restrictions on digestion process product and its micropollutant contents to protect the environment. In this study, a performance of the anaerobic digestion under mesophilic and thermophilic conditions at different hydraulic retention times (HRT) is assessed and the removal efficiencies of two important compounds or family compounds (Polycyclic Aromatic Hydrocarbons, PAH, and Di-2-(Ethyl-Hexyl)-Phthalate, DEHP) are evaluated. A positive effect of thermophilic temperature was observed on both micropollutants' biodegradation. However, HRT effect also had an important role for DEHP and low molecular weighted PAH removal.

Multi-modal language input: A learned superadditive effect

2019 ◽  
Vol 10 (2) ◽  
pp. 179-200 ◽  
Author(s):  
Dominic Cheetham
Keyword(s):  
Language Learning ◽  
Additive Model ◽  
General Effect ◽  
Active System ◽  
Brain Areas ◽  
Early Integration ◽  
Simple Addition ◽  
Illustrated Text ◽  
Text Reading ◽  
Positive Effect

AbstractReview of psychological and language acquisition research into seeing faces while listening, seeing gesture while listening, illustrated text, reading while listening, and same language subtitled video, confirms that bi-modal input has a consistently positive effect on language learning over a variety of input types. This effect is normally discussed using a simple additive model where bi-modal input increases the total amount of data and adds redundancy to duplicated input thus increasing comprehension and then learning. Parallel studies in neuroscience suggest that bi-modal integration is a general effect using common brain areas and following common neural paths. Neuroscience also shows that bi-modal effects are more complex than simple addition, showing early integration of inputs, a learning/developmental effect, and a superadditive effect for integrated bi-modal input. The different bodies of research produce a revised model of bi-modal input as a learned, active system. The implications for language learning are that bi- or multi-modal input can powerfully enhance language learning and that the learning benefits of such input will increase alongside the development of neurological integration of the inputs.

scholarly journals The microbiome and resistome of hospital sewage during passage through the community sewer system

2017 ◽  
Author(s):  
Elena Buelow ◽  
Jumamurat R. Bayjanov ◽  
Rob J.L. Willems ◽  
Marc J.M. Bonten ◽  
Heike Schmitt ◽  
...  
Keyword(s):  
Wastewater Treatment Plants ◽  
Point Sources ◽  
Resistant Bacteria ◽  
Sewer System ◽  
Sewerage System ◽  
Drug Resistant Bacteria ◽  
Wwtp Effluent ◽  
Antimicrobial Resistance Genes ◽  
Culture Independent ◽  
Hospital Sewage

AbstractEffluents from wastewater treatment plants (WWTPs) have been proposed to act as point sources of antibiotic-resistant bacteria (ARB) and antimicrobial resistance genes (ARGs) in the environment. Hospital sewage may contribute to the spread of ARB and ARGs as it contains the feces and urine of hospitalized patients, who are more frequently colonized with multi-drug resistant bacteria than the general population. However, whether hospital sewage noticeably contributes to the quantity and diversity of ARGs in the general sewerage system has not yet been determined.Here, we employed culture-independent techniques, namely 16S rRNA and nanolitre-scale quantitative PCRs, to describe the role of hospital effluent as a point source of ARGs in the sewer system, through comparing microbiota composition and levels of ARGs in hospital sewage with WWTP influent, WWTP effluent and the surface water in which the effluent is released.Compared to other sample sites, hospital sewage was richest in human-associated bacteria and contained the highest relative levels of ARGs. Yet, the abundance of ARGs was comparable in WWTPs with and without hospital wastewater, suggesting that hospitals do not contribute to the spread of ARGs in countries with a functioning sewerage system.

Nitrification Inhibition - A Source Identification Method for Combined Municipal and/or Industrial Wastewater Treatment Plants

1992 ◽  
Vol 26 (5-6) ◽  
pp. 1135-1146 ◽  
Author(s):  
H. Kroiss ◽  
P. Schweighofer ◽  
W. Frey ◽  
N. Matsche
Keyword(s):  
Wastewater Treatment ◽  
Industrial Wastewater ◽  
Wastewater Treatment Plants ◽  
Ammonia Nitrogen ◽  
Nitrification Inhibition ◽  
Sewer System ◽  
Effluent Standards ◽  
Inhibition Of Nitrification ◽  
Short Time ◽  
The Relationship

Inhibition of nitrification at combined municipal and/or industrial treatment plants can cause serve problems in regard to the future low effluent standards for ammonia nitrogen. As inhibition problems often occur only for limited periods and are caused by different substances it is very difficult to find the sources of these substances within the sewer system. Using a two step strategy based on a respiration test it is possible to locate these sources within a short time and to concentrate then on the abatement of the inhibiting wastewaters. The method of the respiration test was developed and the relationship between dilution and inhibition could be described by a new mathematical inhibition model. The method was applied at an Austrian city (Linz) with more than 50% wastewater load coming from industry during the design period for the extension of the existing plant (800 000 PE).

Preparation of Solutions of Titanium Trichloride-Based Complex Coagulants

2021 ◽  
pp. 86-99
Author(s):  
E.N. Kuzin
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Production Method ◽  
Metal Compounds ◽  
Electrochemical Preparation ◽  
Chromium Vi ◽  
Galvanic Production ◽  
Titanium Trichloride ◽  
Positive Effect ◽  
Research Show

One of the largest sources of heavy metal compounds entering the hydrosphere is galvanic production. Despite their high danger, chromium (VI) compounds are widely used in electroplating. Electrolytes based on chromium (VI) compounds are stable at all pH values and, if released into water, pose a serious problem for wastewater treatment plants. The purpose of this study was to assess the possibility of thermal and electrochemical preparation of solutions of complex coagulants-reducing agents based on titanium trichloride for wastewater treatment from chromium (VI) compounds. Findings of research show that the yield of titanium trichloride is practically independent of the production method, however, the process of electrochemical synthesis is much more stable, the reaction mixture is slightly heated, which has a positive effect on the storage time of the obtained reagent solutions. The study proves that in terms of their effectiveness, the samples of the complex coagulant-reducing agent are superior to individual reagents based on iron (II) compounds. Moreover, the use of complex reagents makes it possible to considerably intensify the processes of sedimentation and filtration of the resulting sludge, which allows us to significantly reduce the dimensions of the equipment and increase the economic efficiency of the water purification process as a whole

scholarly journals Method for assessing the impact of rainfall depth on the stormwater volume in a sanitary sewage network

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Edward Kozłowski ◽  
Dariusz Kowalski ◽  
Beata Kowalska ◽  
Dariusz Mazurkiewicz
Keyword(s):  
Mathematical Model ◽  
Wastewater Treatment Plants ◽  
Sewer System ◽  
Urban Floods ◽  
Sanitary Sewer ◽  
Combined Sewer ◽  
Rainfall Depth ◽  
Residuals Analysis ◽  
Local Water ◽  
The Impact

AbstractSanitary sewage network is relatively rarely considered as the cause of urban floods. Its hydraulic overload can result not only in flooding, but also sanitary contamination of subcatchments. Stormwater is the main reason for this overload. In contrast to the stormwater or combined sewer system, these waters infiltrate into the network in an uncontrolled way, through ventilation holes of covers or structural faults and lack of tightness of manholes. Part of stormwater infiltrates into the soil, where it leaks into pipelines. This greatly hinders assessing the quantity of stormwater influent into the sanitary sewer system. Standard methods of finding correlation between rainfall and the intensity of stormwater flow are ineffective. This is confirmed, i.a. by the studies performed in an existing network, presented in this paper. Only when residuals analysis was performed using the ARIMA and ARIMAX methods, the authors were able to develop a mathematical model enabling to assess the influence of rainfall depth on the stormwater effluent from the sewage network. Owing to the possibility of using the rainfall depth forecasts, the developed mathematical model enables to prepare the local water and sewerage companies for the occurrence of urban floods as well as hydraulic overload of wastewater treatment plants.

scholarly journals On the dynamics and feasibility of transferred inference for diagnosis of invasive ductal carcinoma: A perspective

2021 ◽  
Author(s):  
Harshvardhan GM ◽  
Aanchal Sahu ◽  
Mahendra Kumar Gourisaria ◽  
Vijander Singh ◽  
Bunil Kumar Balabantaray ◽  
...  
Keyword(s):  
Invasive Ductal Carcinoma ◽  
Performance Metrics ◽  
Ductal Carcinoma ◽  
State Of The Art ◽  
Model Performance ◽  
Optimization Procedure ◽  
Avant Garde ◽  
Proper Diagnosis ◽  
Classification Procedures ◽  
Behavioural Aspects

Abstract It is generally noticed that increasing the number of convolutional layers in generic image classification procedures proves to be detrimental to model performance in terms of validation accuracy and loss. Apart from vanilla CNNs, we have state-of-the-art (SOTA) architectures such as ResNet50 (and its variants) which show that through the use of skip-connections, higher performance metrics are attainable through deeper architectures. However, most evaluative metrics converge on a log scale as we go deeper with diminishing gradient of the metrics' curves. Given these two contrasting speculations, in this paper, we implement various vanilla and SOTA CNNs for the diagnosis of one of the most common forms of breast cancer - invasive ductal carcinoma (IDC) - to examine and understand the feasibility of implementation of SOTA CNNs through transferred weights when juxtaposed with vanilla CNNs (and LeNet-5) of varying configurations in terms of their performance metrics and other parameters. In this paper, we solve the dual-objective of studying behavioural aspects of avant-garde CNN models (more specifically, VGG16, VGG19, ResNet50, ResNet50V2, MobileNetV2, and DenseNet121) and proper diagnosis of IDC through intermediate neural activations to critically evaluate and theorize the performance of different models. We notice that among all the models, only VGG16, VGG19, LeNet-5 and a selected vanilla CNN through an optimization procedure were the ones to attain the best metrics, shared amongst them.

The use of an on-line respirometer for the screening of toxicity in the antwerp WWTP catchment area

1998 ◽  
Vol 37 (12) ◽  
pp. 213-218 ◽  
Author(s):  
D. Geenens ◽  
C. Thoeye
Keyword(s):  
Activated Sludge ◽  
Wastewater Treatment Plants ◽  
Nitrification Inhibition ◽  
Environmental Legislation ◽  
Sewer System ◽  
Total Phosphorous ◽  
Wwtp Effluent ◽  
Pilot Work ◽  
On Line ◽  
Activated Sludge Processes

Following the new European and Flemish environmental legislation most of the existing Flemish wastewater treatment plants (WWTP) have to be adapted to achieve nutrient removal. The Antwerp WWTP Deurne-Schijnpoort (230,000 PE) is to be renovated to achieve a 10 mg/l total nitrogen and a 1 mg/l total phosphorous effluent consent. Six months of intensive pilot work at this plant has shown total nitrification inhibition of one- stage activated sludge processes. A mobile on-line respirometer was installed to monitor the activated sludge inhibition at the WWTP. Toxicity resulting in a substantial deterioration of the WWTP effluent was observed. Industrial discharges and main junctions in the sewer system were sampled for specific monitoring. An industrial source of inhibition could be pinpointed. Full-scale operating experiences with the respirometer during the measurements are reported.

Integrated design of sewers and wastewater treatment plants

2002 ◽  
Vol 46 (9) ◽  
pp. 11-20 ◽  
Author(s):  
J. Vollertsen ◽  
T. Hvitved-Jacobsen ◽  
Z. Ujang ◽  
S.A. Talib
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Integrated Design ◽  
Cost Effective ◽  
Wastewater Management ◽  
Plant Design ◽  
Sewer System ◽  
Process Simulations

Sewer system design must be integrated with wastewater treatment plant design when moving towards a more sustainable urban wastewater management. This integration allows an optimization of the design of both systems to achieve a better and more cost-effective wastewater management. Hitherto integrated process design has not been an option because the tools to predict in-sewer wastewater transformations have been inadequate. In this study the WATS model - being a new and validated tool for in-sewer microbial process simulations - is presented and its application for integrated sewer and treatment plant design is exemplified. A case study on a Malaysian catchment illustrates this integration. The effects of centralization of wastewater treatment and the subsequently longer transport distances are addressed. The layout of the intercepting sewer is optimized to meet the requirements of different treatment scenarios.

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