Polyphonic sonification of electrocardiography signals for diagnosis of cardiac pathologies

Kather JN, Hermann T, Bukschat Y, Kramer T, Schad LR, Zöllner FG. Polyphonic sonification of electrocardiography signals for diagnosis of cardiac pathologies. Scientific Reports. 2017;7(1): 44549.Electrocardiography (ECG) data are multidimensional temporal data with ubiquitous applications in the clinic. Conventionally, these data are presented visually. It is presently unclear to what degree data sonification (auditory display), can enable the detection of clinically relevant cardiac pathologies in ECG data. In this study, we introduce a method for polyphonic sonification of ECG data, whereby different ECG channels are simultaneously represented by sound of different pitch. We retrospectively applied this method to 12 samples from a publicly available ECG database. We and colleagues from our professional environment then analyzed these data in a blinded. Based on these analyses, we found that the sonification technique can be intuitively understood after a short training session. On average, the correct classification rate for observers trained in cardiology was 78%, compared to 68% and 50% for observers not trained in cardiology or not trained in medicine at all, respectively. These values compare to an expected random guessing performance of 25%. Strikingly, 27% of all observers had a classification accuracy over 90%, indicating that sonification can be very successfully used by talented individuals. These findings can serve as a baseline for potential clinical applications of ECG sonification

Großpumpversuch Horkheimer Insel : analytische Auswertung

Ein maßgebliches Forschungsziel des genannten PWAB-Projektes ist die Identifikation des hydraulischen Durchlässigkeitsfeldes mit Hilfe von verschiedenen Erkundungsmethoden sowie eine Bewertung der eingesetzten Methoden. Daneben kommt der Problematik des Übergangs von klein- zu großskaligen Erkundungen besondere Bedeutung zu. Während der ersten Projektphase wurden vor allem im Bereich des nordwestlichen Teilfeldes an vielen Beobachtungsmeßstellen sogenannte Kleinpumpversuche durchgeführt. Dabei wurde das Grundwasser über einen Zeitraum von jeweils 2 Stunden abgesenkt. Das Absenkungsverhalten des Aquifers wurde an mehreren umliegenden Meßstellen aufgezeichnet. Als Vergleich zu diesen kleinskaligen Erkundungen wurde die Durchführung eines Großpumpversuchs projektiert. Damit sollten zum einen effektive Aquiferparameter ermittelt und zum anderen eine Untersuchung der Abhängigkeit der ermittelten hydraulischen Parameter vom Abstand zwischen Pump- und Beobachtungsbrunnen ermöglicht werden

Untersuchungen zur Erkundung effektiver Aquiferparameter : Testfeld WASSER/BODEN "Horkheimer Insel" ; Schadstofftransport im Untergrund, Erkundungs- und Überwachungsmethoden

Die Kenntnis der hydraulischen Parameter Durchlässigkeit und Speichervermögen eines Aquifers ist die entscheidende Voraussetzung für die Berechnung bzw. Modellierung von Strömungs- und Transportvorgängen im Grundwasser. In heterogenen Systemen stellt insbesondere die hydraulische Durchlässigkeit jedoch keine Konstante dar, sondern variiert räumlich teilweise um mehrere Größenordnungen. In porösen Medien - wie dem Horkheimer Testfeldaquifer - ist diese Variabilität vor allem sedimentalogisch bedingt und unterliegt in der Regel einer räumlichen Struktur. Aufgrund der Unkenntnis der physikalischen Prozeßparameter der Sedimentation bzw. des enormen Aufwandes diese Struktur deterministisch zu erkunden, wird die hydraulische Durchlässigkeit als das Ergebnis eines stochastischen Prozesses betrachtet und durch statistische und geostatistische Strukturparameter beschrieben

Field application of a tailored catalyst for hydrodechlorinating chlorinated hydrocarbon contaminants in groundwater

Catalytic hydrodechlorination via Pd catalysts is an efficient way to destroy chlorinated hydrocarbon compounds (CHCs) in aqueous systems. However, its application in groundwater suffers from rapid catalyst deactivation, e.g. by sulfur poisoning and interference with biological processes, such as growth of sulfate-reducing bacteria. In this paper we describe the application of a tailored catalyst for groundwater remediation in a full-scale field installation. The catalyst (Pd on a hydrophobic zeolite Y) was operated in a flow-through mode over 2 years and showed sustained removal efficiencies. Typical half-lives for CHC reduction were between 1.5 and 3min. As the addition of the reductant hydrogen results in favorable conditions for sulfate-reducing bacteria, the system was periodically flushed with a dilute H2O2solution to prevent the growth of this type of bacteria. With this it could be shown, that a catalytic method with noble metals for the direct reductive destruction of chlorinated contaminants in groundwater can be operated over extended periods of time with sustained efficiencies. © 2004 Elsevier B.V. All rights reserved

Supplementary Material for "Polyphonic sonification of electrocardiography signals for diagnosis of cardiac pathologies"

Kather JN, Hermann T, Bukschat Y, Kramer T, Schad LR, Zöllner FG. Supplementary Material for "Polyphonic sonification of electrocardiography signals for diagnosis of cardiac pathologies". Bielefeld University; 2017.#### S1: Normal ECG sample <img src="https://pub.uni-bielefeld.de/download/2908653/2908701" width="40%" height="40%" style="float:right;" > Description: This supplementary material contains ECG data sonification of a healthy control. * [s0306lrem.wav](https://pub.uni-bielefeld.de/download/2908653/2908702) contains sound data for a six-channel data set, 10 seconds * [s0306lrem.png](https://pub.uni-bielefeld.de/download/2908653/2908701) contains the corresponding visual data, 10 seconds, sampling rate of 1000 Hz #### S2: Incremental signal Description: This supplementary material contains an incremental number of channels from a pathological (STEMI) ECG data sonification <img src="https://pub.uni-bielefeld.de/download/2908653/2908709" width="40%" height="40%" style="float:right;" > - [incremental_01.wav](https://pub.uni-bielefeld.de/download/2908653/2908703) only channel III (lowest), 10 seconds - [incremental_02.wav](https://pub.uni-bielefeld.de/download/2908653/2908704) channel III and aVF, 10 seconds - [incremental_03.wav](https://pub.uni-bielefeld.de/download/2908653/2908705) channel III and aVF and II, 10 seconds - [incremental_04.wav](https://pub.uni-bielefeld.de/download/2908653/2908706) channel III and aVF and II and -aVR, 10 seconds - [incremental_05.wav](https://pub.uni-bielefeld.de/download/2908653/2908707) channels III through I, 10 seconds - [incremental_06.wav](https://pub.uni-bielefeld.de/download/2908653/2908708) all channels, 10 seconds - [incremental_signal.png](https://pub.uni-bielefeld.de/download/2908653/2908709) shows the corresponding visual data, 10 seconds, sampling rate of 257 Hz #### S3: Pathological ECG samples Description: This supplementary material contains sonified ECG data of four pathological samples, corresponding to Figure 2 in the main manuscript. All samples are 10 seconds in length (original sound file in sub-folder “original”, amplified sound file in sub-folder “amplified”). - [Sample_I04m_STEMI.wav](https://pub.uni-bielefeld.de/download/2908653/2908710) ST-elevation myocardial infarction - [Sample_I37m_PVC.wav](https://pub.uni-bielefeld.de/download/2908653/2908711) Premature ventricular contraction - [Sample_I50m_AF.wav](https://pub.uni-bielefeld.de/download/2908653/2908712) Atrial fibrillation - [Sample_I51m_Bigeminy.wav](https://pub.uni-bielefeld.de/download/2908653/2908713) Bigeminy #### S4: Flowchart of the algorithm File: [S4_sonification_procedure_schematic.pdf](https://pub.uni-bielefeld.de/download/2908653/2908714) Description: This PDF is a detailed flowchart of the algorithm including all relevant parameters. This can be used to implement our proposed method in any programming language. #### S5: Observer performance during data analysis File: [S5_performance_data.xls](https://pub.uni-bielefeld.de/download/2908653/2908715) Description: The spreadsheet contains all results of the data analysis by 22 blinded observers in three groups. S1 to S12 refer to the ECG samples, the number in each cell in these columns shows the classification by the observer. Correct classifications are shown in green, errors are shown in red. “Instrument” denotes whether the observer had been actively playing an instrument for three or more years at any time during their life. #### S6 Source code of Polyphonic ECG Sonification (in SuperCollider3) File: [S6_Polyphonic-ECG-Sonification.zip](https://pub.uni-bielefeld.de/download/2908653/2908761) Description: The zipped folder contains the Supercollider3 source code, two data files in csv format and the resulting sonifications for Polyphonic ECG Sonification. Instructions for how to render the sonifications are given in the source code header. #### S7 Source code of Polyphonic ECG Sonification (Matlab) File: [S7_Polyphonic-ECG-Sonification-matlab.zip](https://pub.uni-bielefeld.de/download/2908653/2908760) Description: This file contains the source code in matlab which was also used for the rendering of sonifications in the study