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Koc, Bengi. "Detection And Classification Of Qrs Complexes From The Ecg Recordings." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/2/12610328/index.pdf.
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Electrocardiography (ECG) is the most important noninvasive tool used for diagnosing heart diseases. An ECG interpretation program can help the physician state the diagnosis correctly and take the corrective action. Detection of the QRS
complexes from the ECG signal is usually the first step for an interpretation tool. The main goal in this thesis was to develop robust and high performance QRS detection algorithms, and using the results of the QRS detection step, to classify these beats according to their different pathologies. In order to evaluate the performances, these algorithms were tested and compared in Massachusetts Institute of Technology Beth Israel Hospital (MIT-BIH) database, which was developed for research in cardiac electrophysiology.
In this thesis, four promising QRS detection methods were taken from literature and implemented: a derivative based method (Method I), a digital filter based method (Method II), Tompkin&rsquos method that utilizes the morphological features of the ECG signal (Method III) and a neural network based QRS detection method (Method IV). Overall sensitivity and positive predictivity values above 99% are achieved with each method, which are compatible with the results reported in literature. Method III has the best overall performance among the others with a sensitivity of 99.93% and a positive predictivity of 100.00%. Based on the detected QRS complexes, some features were extracted and classification of some beat types were performed. In order to classify the detected beats, three methods were taken from literature and implemented in this thesis: a Kth nearest neighbor rule based method (Method I), a neural network based method (Method II) and a rule based method (Method III). Overall results of Method I and Method II have sensitivity values above 92.96%. These findings are also compatible with those reported in the related literature. The classification made by the rule based approach, Method III, did not coincide well with the annotations provided in the MIT-BIH database. The best results were achieved by Method II with the overall sensitivity value of 95.24%.
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Malina, Ondřej. "Detekce začátku a konce komplexu QRS s využitím hlubokého učení." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442595.
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This thesis deals with the issue of automatic measurement of the duration of QRS complexes in ECG signals. Special emphasis is then placed on the possibility of automatic detection of QRS complexes while exciting cardiac tissue with a pacemaker. The content of this work is divided into four logical units, where the first part deals with the heart as an organ. It describes the origin and spread of excitement in the heart, its possible pathologies and their manifestations in ECG recording, it also deals with pacing and measuring ECG recording during simultaneous pacing. The second part of the thesis contains a brief introduction to the topic of machine and deep learning. The third part of the thesis contains a search of current approaches using methods based on deep learning to solve the detection of QRSd. The fourth part deals with the design and implementation of its own model of deep learning, able to detect the beginnings and ends of QRS complexes from ECG recordings. It describes the data preprocessing implemented in the MATLAB programming environment. The actual implementation of the model was performed in the Python using the PyTorch and NumPy moduls.
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Hráček, Roman. "Softwarový balík pro frekvenční metody detekce QRS komplexu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221390.
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Engström, Magnus, and Nadia Soheily. "EKG-analys och presentation." Thesis, KTH, Data- och elektroteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-154539.
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Tolkningen av EKG är en viktig metod vid diagnostisering av onormala hjärttillstånd och kan användas i förebyggande syfte att upptäcka tidigare okända hjärtproblem. Att enkelt kunna mäta sitt EKG och få det analyserat och presenterat på ett pedagogiskt sätt utan att behöva rådfråga en läkare är något det finns ett konsumentbehov av. Denna rapport beskriver hur en EKG-signal behandlas med olika algoritmer och metoder i syfte att detektera hjärtslag och dess olika parametrar. Denna information används till att klassificera varje hjärtslag för sig och därmed avgöra om användaren har en normal eller onormal hjärtfunktion. För att nå dit har en mjukvaruprototyp utvecklats där algoritmerna implementerats. En enkätundersökning gjordes i syfte att undersöka hur utdata från mjukvaruprototypen skulle presenteras för en vanlig användare utan medicinsk utbildning. Sju filer med EKG-signaler från MIT-BIH Arrhythmia Database användes för testning av mjukvaruprototypen. Resultatet visade att prototypen kunde detektera en rad olika hjärtfel som låg till grund vid fastställning om hjärtat slog normalt eller onormalt. Resultatet presenterades på en mobilapp baserad på enkätundersökningen.The interpretation of the ECG is an important method in the diagnosis of abnormal heart conditions and can be used proactively to discover previ-ously unknown heart problems. Being able to easily measure the ECG and get it analyzed and presented in a clear manner without having to consult a doctor is improtant to satisfy consumer needs. This report describes how an ECG signal is treated with different algo-rithms and methods to detect the heartbeat and its various parameters. This information is used to classify each heartbeat separately and thus determine whether the user has a normal or abnormal cardiac function. To achieve this a software prototype was developed in which the algorithms were implemented. A questionnaire survey was done in order to examine how the output of the software prototype should be presented for a user with no medical training. Seven ECG files from MIT-BIH Arrhythmia database were used for validation of the algorithms. The developed algorithms could detect of if any abnormality of heart function occurred and informed the users to consult a physician. The presentation of the heart function was based on the result from the questioner.
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Klingspor, Måns. "Hilbert Transform : Mathematical Theory and Applications to Signal processing." Thesis, Linköpings universitet, Matematik och tillämpad matematik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-122736.
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The Hilbert transform is a widely used transform in signal processing. In this thesis we explore its use for three different applications: electrocardiography, the Hilbert-Huang transform and modulation. For electrocardiography, we examine how and why the Hilbert transform can be used for QRS complex detection. Also, what are the advantages and limitations of this method? The Hilbert-Huang transform is a very popular method for spectral analysis for nonlinear and/or nonstationary processes. We examine its connection with the Hilbert transform and show limitations of the method. Lastly, the connection between the Hilbert transform and single-sideband modulation is investigated.
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Brandejs, Jakub. "Detekce parametrů repolarizace ze signálu EKG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220848.
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A T wave peak and offset detector based on an unpublished lead transformation that can be briefly described as multilead linear regression was proposed and implemented afterwards. Potential of the transformation as a useful QRS detection tool was revealed later on. Proposed QRS detector was put to the test of CSE database. Results were compared with work of other authors. Results of T wave peak and offset detector were introduced in visual way.
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Hanzelka, Adam. "Rozměřování experimentálních záznamů EKG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220063.
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This master's thesis deals with an analysis of principles of ECG signals detection and delineation. The theoretical part describes heart electrophysiology and electrocardiography basics. Next, the most important QRS detection and ECG delineation algorithms are introduced. Especially the wavelet transform methods are described. In the practical part proper delineation algoriythm was realized. It was tested on the standard CSE database, then it was modified on data of isolated rabbit heartsand the results are published in the conclusion.
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Bajgar, Jiří. "Detekce P vlny v EKG signálech." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221317.
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The aim of this diploma thesis is to introduce methods of detection of the QRS complex and the subsequent detection of P waves. The intention is to create a program by specified method in the software Matlab which will be able to implement this method. The thesis describes the basic and important methods of detection and subsequent algorithm to detect P waves. Solution of the algorithm is tested on real data. It also describes the automatic signal evaluation and the results of this automatic function.
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Bucsuházy, Kateřina. "Rozměření experimentálních záznamů EKG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221318.
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This master thesis deals with QRS complex detection and ECG delineation. The theoretical part of this work describes wavelet transform, some of QRS detection approaches and some of ECG delineation approaches. For algorithm realization in Matlab is used redundant dyadic discrete wavelet transform. Algorithm is designed for experimental electrocardiograms of isolated rabbit hearts and it is evaluated through manually determined references.
10
Zaeid, Jabar, and Andreas Lind. "Utveckling av ny teknik för hjärtpulsdetektion." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-211571.
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In this thesis we suggest a technique for detecting pulses by signal processing of a raw ECG signal registered from 4 electrodes located on the left upper arm. The signal processing is performed in Matlab and consists of normalization, lowpass filtering, highpass filtering, derivation, squaring and a moving average window to reduce interference. The technology is capable of extracting periods between heartbeats after an implemented detection algorithm. The thesis also includes reflections on the types of interferences that may affect an electrical development equipment and also methods of how major parts of the interference can be reduced by different shields. Before the technique is applied in a final product, further tests may need to be performed during the monitoring of a person's pulse. Finally, we believe that our development of pulse detection is the beginning of a new technology that in the future can save lives.I den här rapporten föreslår vi en teknik för att detektera pulser med hjälp av att signalbehandla en rå EKG-signal registrerad från 4 elektroder placerade på vänster överarm. En signalbehandling utförd i Matlab som bland annat består av normering, lågpassfiltrering, högpassfiltrering, derivering, kvadrering samt ett glidande medelvärdesfönster för att reducera störningar. Tekniken är kapabel till att utvinna tider mellan hjärtslag efter en implementerad detekteringsalgoritm. Rapporten innefattar även reflektioner kring vilka typer av störningar som kan påverka en elektrisk utvecklingsutrustning samt metoder för hur större delar av störningarna kan reduceras med hjälp av olika skärmningar. Innan tekniken appliceras i en slutlig produkt kan ytterligare tester behöva utföras under monitorering av en persons puls. Slutligen anser vi att våran utveckling av pulsdetektion är en början på en ny teknik för att kunna rädda liv.
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Hejč, Jakub. "Rozměřování experimentálních záznamů EKG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220336.
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This thesis deals with a proposition of an algorithm for QRS complex and typical ECG waves boundaries detection. It incorporates a literature research focused on heart electrophysiology and commonly used methods for ECG fiducial points detection and delineation. Out of the presented methods an algorithm based on a continuous wavelet transform is implemented. Detection and delineation algorithm is tested on CSE standard signal database towards references determined both manually and automatically. Obtained results are compared to other congenerous methods. The diploma thesis is further concerned with an algorithm modification for experimental electrocardiograms of isolated rabbit hearts. Recording specifics of these data are introduced. Additionally, based on time and frequency analysis, particular modifications of the algorithm are proposed and realized. Due to a large extent of records functionality is verified on randomly selected database samples. Efficiency of the modified algorithm is evaluated through manually annotated references.
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Zedníček, Vlastimil. "Detekce QRS založená na vlnkové transformaci." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220878.
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This thesis deals with implementation of detector QRS complex with use of wavelet transform. The first part is focused on formation and possibility to measure cardiac activity. The other part of thesis we will familiarise with the different possibilities of detection QRS complex and we intimately focus on wavelet transform that will be used for a project of detection QRS complex. The practical part of thesis focuses on the project of detector in programming language Matlab and his different setting. This projected detector has been tested with CSE database. Achieved results of projected detector are evaluated with the results of others authors.
13
Janjarasjitt, Suparerk. "A NEW QRS DETECTION AND ECG SIGNAL EXTRACTION TECHNIQUE FOR FETAL MONITORING." Case Western Reserve University School of Graduate Studies / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=case1144263231.
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Hanus, Rostislav. "Detekce QRS založená na počítání průchodů nulou." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219638.
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This master’s thesis deals with the detection of QRS complex detection using zero crossing counts. QRS detection is an important part of the analysis of ECG signal. From the point of determining the R wave detection is based on the other waves and intervals necessary for the diagnosis of heart. This method is very effective even for very noisy signals. Implementation of the method in Matlab, and the success of detection is tested on the CSE and MIT-BIH database. The optimization algorithm is an optional value for the detector.
15
Hylmar, Petr. "Detekce QRS založená na počítání průchodů nulou." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220865.
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This master's thesis describes basics principles of QRS complex detection. It is focused on QRS detection using zero crossing counts method. There are described princips and program realization of this method. The other part is focused on genetic optimalization algorithm. There are presented obtained optimalization results on standard CSE and MIT-BIH database. The quality of the detector is compared with other authors. The optimalized QRS detector achieves comparable results with other authors. The part of the thesis is graphical user interface which supply view on modified ECG signal and detection results.
16
Loviška, David. "Detekce QRS komplexu s využitím vlnkové transformace." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218652.
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The aim of diploma thesis named “QRS detection using wavelet transform” is to simplify and accelerate the work of doctors. This can be achieved by using application for QRS detection, which can use one of four proposed algorithms. Application shows basic informations about inserted electrocardiogram. Part of this program is a graphical window with displayed record and with coloured marks on detected QRS complexes. By another algorythm are marks color-coded due to accurancy percentil of every detected complex. This program is designed for a several hours record from Holter ECG monitoring.
17
Ieong, Chio In. "ECG QRS complex detection with programmable hardware = 心電圖QRS複合波檢測算法及可編程器件實現." Thesis, University of Macau, 2008. http://umaclib3.umac.mo/record=b1939516.
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Spáčil, Jakub. "Optimální detekce hranic QRS komplexu v EKG signálech." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218719.
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This diploma thesis deals with location optimal wavelet for detecton charakterics points of QRS complex in ECG signals. The first part of this thesis deals with description of heart, genesis of electric signals on heart and problem of noise. The second part describes the wavelet transform and the designed program and the third part evaluate detection results. The created program is working with 10 ECG signals from the CSE database and is testing 12 different mother wavelets. The program was developed in Matlab environment and is based on the finding zero-points in the transformed signal.
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Kocian, Ondřej. "Detekce komplexů QRS s využitím vlnkové transformace." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-217974.
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This project investigates methods of construction the wavelet-based QRS-complex detector. QRS-complex detection is very important, because it helps automatically calculate heart rate and in some cases it is used for compression ECG signal. The design of QRS detector can be made with many methods, in this project were mentioned and consequently tested only a few variants. The principle of designed detector used a wavelet-based decomposition of the original ECG signal to several frequency-coded bands. These bands are consequently transformed to absolute values and with the help of the threshold value are marked positions of assumed QRS complexes. Then are these assumed positions from all bands compared between themselves. If the position is confirmed at least at one nearby band, then is this position marked as true QRS complex. To increase efficiency of designed detector, two modifications were additionally mentioned. The first one, using the envelope of the signal, had rather negative effect on detectors efficiency. The second modification, using combined signal from three pseudoorthogonal leads, had reversely very good effect on detectors efficiency. In the end, the designed detector and all its modifications were tested on signals from CSE library (exactly on leads II, V2 and V6).
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Syed, Shah Nemath Farhan. "IMPLEMENTATION OF INTERACTIVE REMOTE PHYSIOLOGICAL MONITORING AND FEEDBACK TRAINING SYSTEM." University of Akron / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=akron1164666232.
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Ondráček, Vladimír. "Měření QT intervalu v elektrokadiografických záznamech." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218650.
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This diploma thesis focuses on determination of the QT interval in ECG. The thoretical part desribes physiology of the heart, electronic activity of the heart and possible methods of ECG measurement. The theoretical part also describes methods of signal processing, the processed signal is then used for determination of the QT interval. The practical part focuses on two chosen methods of QT interval determination and on implementation of the methods in a computer program. The results part is evaluation of measured QT intervals and a comparision of the results with reference values.
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Henry, Didier. "Contribution à la détection et à la reconnaissance d'événements dans les signaux biomédicaux : applications à la détection de complexes QRS dans le signal ECG et de complexes K dans le signal EEG." Nancy 1, 1994. http://www.theses.fr/1994NAN10218.
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La détection et la reconnaissance d'événements dans les signaux biomédicaux ECG et EEG font l'objet de ce mémoire. Celui-ci est composé de trois parties. La première est consacrée à une description physiologique des signaux ECG et EEG. Dans la seconde, nous présentons et nous comparons plusieurs méthodes de détection du complexe QRS dans le signal ECG et du complexe K dans le signal EEG, basées sur la reconnaissance de forme. La troisième partie présente une approche plus générale consistant à effectuer la projection du signal étudié suivant une ou plusieurs fonctions élémentaires dépendant de un ou plusieurs paramètres, puis à étudier les coefficients obtenus pour détecter l'événement recherché. Les méthodes de détection présentées dans cette partie sont construites à partir du filtrage adapté, de la décomposition en séries de fonctions orthonormales et enfin de la transformée en ondelettes. Ces trois méthodes sont comparées en simulation, puis sont appliquées successivement à la détection du complexe QRS et du complexe K
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Hammond, Maria. "DNA-Mediated Detection and Profiling of Protein Complexes." Doctoral thesis, Uppsala universitet, Molekylära verktyg, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-204861.
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Proteins are the effector molecules of life. They are encoded in DNA that is inherited from generation to generation, but most cellular functions are executed by proteins. Proteins rarely act on their own – most actions are carried out through an interplay of tens of proteins and other biomolecules. Here I describe how synthetic DNA can be used to study proteins and protein complexes. Variants of proximity ligation assays (PLA) are used to generate DNA reporter molecules upon proximal binding by pairs of DNA oligonucleotide-modified affinity reagents. In Paper I, a robust protocol was set up for PLA on paramagnetic microparticles, and we demonstrated that this solid phase PLA had superior performance for detecting nine candidate cancer biomarkers compared to other immunoassays. Based on the protocol described in Paper I I then developed further variants of PLA that allows detection of protein aggregates and protein interactions. I sensitively detected aggregated amyloid protofibrils of prion proteins in paper II, and in paper III I studied binary interactions between several proteins of the NFκB family. For all immunoassays the selection of high quality affinity binders represents a major challenge. I have therefore established a protocol where a large set of protein binders can be simultaneously validated to identify optimal pairs for dual recognition immunoassays (Paper IV).
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Rörbrink, Malin. "Improving detection of promising unrefined protein docking complexes." Thesis, Linköpings universitet, Bioinformatik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-133633.
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Understanding protein-protein interaction (PPI) is important in order to understand cellular processes. X-ray crystallography and mutagenesis, expensive methods both in time and resources, are the most reliable methods for detecting PPI. Computational approaches could, therefore, reduce resources and time spent on detecting PPIs. During this master thesis a method, cProQPred, was created for scoring how realistic coarse PPI models are. cProQPred use the machine learning method Random Forest trained on previously calculated features from the programs ProQDock and InterPred. By combining some of ProQDock’s features and the InterPred score from InterPred the cProQPred method generated a higher performance than both ProQDock and InterPred. This work also tried to predict the quality of the PPI model after refinement and the chance for a coarse PPI model to succeed at refinement. The result illustrated that the predicted quality of a coarse PPI model also was a relatively good prediction of the quality the coarse PPI model would get after refinement. Prediction of the chance for a coarse PPI model to succeed at refinement was, however, without success.
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Leung, Ka Ho. "Oligonucleotide-based lunimescent detection platform utilizing iridium (III) complexes." HKBU Institutional Repository, 2015. https://repository.hkbu.edu.hk/etd_oa/163.
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Luminescent transition metal complexes have arisen as viable alternatives to organic dyes for sensory applications due to their notable advantages. This thesis aimed to synthesize different kinds of Ir(III) complexes, explore their interactions with DNAs and investigate their application for the construction of label-free oligonucleotide-based sensing platforms. A series of Ir(III) complexes incorporating a variety of C^N and N^N donor ligands were synthesized and were shown to exhibit G-quadruplex-selective binding properties via emission titration, UV/vis titration, fluorescence resonance energy transfer melting and G-quadruplex fluorescent intercalator displacement experiments. These G-quadruplex-selective Ir(III) complexes were utilized as signal transducers to monitor the conformational changes of oligonucleotides in label-free oligonucleotide-based luminescent detection platforms for metal ion (Sr2+), small molecules (GSH and ATP), protein (human neutrophil elastase) and enzyme activities (polymerase, hepatitis C virus NS3 helicase).
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Richter, Zdeněk. "Vícesvodová rozhodovací pravidla v rozměřování signálů EKG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219529.
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This work deals with ECG signal measuring and methods of its processing. It compares some of the QRS detection methods and describes some of the testing databases. In this work a detector of QRS complex is realized, it is based on the approach of zero crossings. Next section makes combination of results from separate leads to one, which improves efficiency of detection. One section of this work deals with design and realization delination of ECG signal. In the last part outputs of this delineation are compared with the results of the other authors.
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Toušek, Vojtěch. "Detekce a rozměřování v signálu EKG." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217208.
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Automatic detection and delineation of ECG characteristic points is a basic procedure of any analyze of ECG using computer. This detection is a necessary step to simplify the work of cardiologists to evaluate long ECG records. In this thesis is proposed and evaluate a method of detection and delineation in a single-lead ECG using dyadic wavelet transform followed by correction in pseudo-orthogonal lead system taken from standard 12-lead system. The method uses information about position of positive maximum – negative minimum pair to detect ECG characteristic waves. At first the QRS complex is detected and than its morphology (waves Q and S) and the onset and end of the complex. After that the T-wave is detected and delineated within a searching window dependent on QRS position. And last the P-wave is detected and delineated. There are used two types of wavelets in developed method, “haar” and “quadratic spline”. The developed method was evaluated on CSE database. When haar wavelet was used the QRS detector sensitivity was 99.14%. In the work is also evaluated the accuracy of delineation characteristic points. As the P-wave and QRS complex delineation produced quite good results the T-wave end delineator produced relatively big deviations. All deviations are presented in histograms.
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Kalous, Stanislav. "Shluková analýza v oblasti biosignálů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217212.
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This diploma thesis deals with cluster analysis for long-term electrocardiograms (ECG) clustering. The linear filtration is used for ECG preprocessing. The ECG sign segmenting in single heart cycles is based on the detection QRS complex and consequently to an application of dynamic time warping algorithms. To an application of all these mentioned processes and to results interpretation, a program called Cluster analysis has been created in the Matlab background. The results of this diploma thesis confirm that cluster analysis is able to distinguish cardiac arrhythmias which are typical with their shape distinctness of normal heart cycles.
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Li, Yelei. "Heartbeat detection, classification and coupling analysis using Electrocardiography data." Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1405084050.
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Macková, Pavlína. "EKG biofeedback." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219742.
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The master’s thesis is focused on the possibilities of measuring heart rate of ECG signal and its use in therapeutic game of ECG biofeedback. This thesis describes the way of measuring ECG with acquisition unit Biopac and analyzes signal processing for measurement of heart rate – algorithms of QRS detection, HRV analysis. Realisation of therapeutic is designed for applications in Matlab.
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Al, Abdel Hamid Amer A. G. "Chelation and Detection of Mercury in Aqueous Media." Fogler Library, University of Maine, 2009. http://www.library.umaine.edu/theses/pdf/AlAbdelHamidAAG2009.pdf.
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Lin, Sheng. "Cyclometalated iridium (III) complexes and their applications in the detection of biomarkers." HKBU Institutional Repository, 2019. https://repository.hkbu.edu.hk/etd_oa/621.
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Luminescent transition metal complexes have arisen as viable alternatives to organic dyes for sensory applications due to their notable advantages. This thesis aimed to synthesize different kinds of iridium(III) complexes, explore their interactions with DNAs and investigate their application for the construction of oligonucleotide-based sensing platforms for important biomarkers. A series of iridium(III) complexes incorporating a variety of C^N and N^N donor ligands were synthesized and were demonstrated to possess G-quadruplex-selective binding properties via emission titration, UV/vis titration, fluorescence resonance energy transfer melting and G-quadruplex fluorescent intercalator displacement experiments. These G-quadruplex-selective iridium(III) complexes were utilized as signal transducers to monitor the conformational changes of oligonucleotides in oligonucleotide-based luminescent detection platforms for protein tyrosine kinase-7, interferon-gamma, sialic acidbinding immunoglobulin-likelectin-5 and thymine DNA glycosylase. And these designed platforms could work effectively in the diluted cell extract as the results in this thesis indicated.
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Řezáč, Petr. "Rozměření signálu EKG pro analýzu TWA." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217734.
Full textAbstract:
The thesis deals with possibilities of using wavelet transform in the field of surface electrocardiogram (ECG) signals denoising and ECG signals measuring. Several algorithms have been used to detect and estimate T-wave alternans (TWA), such as spectral method (SM), Poincaré Mapping (PM) or correlation method (CM). T-wave alternans, also called repolarization alternans, is a phenomenon appearing in the electrocardiogram as a consistent fluctuation in the repolarization morphology on every-other-beat basis. Electrical TWA has been recognized as a marker of electrical instability, and has been shown to be related with patients at increased risk for ventricular arrhytmias. Presence of TWA has been reported in a wide range of clinical and experimental situations including long QT syndrome, myocardial infarction, angina pectoris, acute ischemia, etc. Projected methods of detection TWA are realized in Matlab software, and they are experimentally verified on real ECG signals from the European ST-T Database.
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Vítek, Martin. "Automatické rozměření signálů EKG." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-233535.
Full textAbstract:
This dissertation deals with QRS complex detection and ECG delineation. The theoretical part of the work describes basics of electrocardiography, QRS detection approaches, ECG delineation approaches, the standard CSE database and the wavelet transform theory. The practical part of the work describes designed methods of QRS complex detection and ECG delineation. The designed methods are based on a continuous wavelet transform, appropriate scales, appropriate mother wavelet, cluster analysis and leads transformation. The introduced algorithms were evaluated on the standard CSE database. The obtained results are better, than directly comparable results of other methods and accomplished given database criteria. The robustness of designed algorithms was successfully tested on CSE database signals modified by compression and filtering. The proposed ECG delineation algorithm was successfully used as a tool for evaluation of diagnostic distortion of ECG signals modified by compression.
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Tennyson, Andrew Gregory. "The detection of nitric oxide and its reactivity with transition metal thiolate complexes." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/43767.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2008.Vita.
Includes bibliographical references.
Nitric oxide (NO) is a molecule that is essential for life and regulates both beneficial and harmful processes. Because this gaseous radical influences many aspects of health and disease, we wish to explore the relationship between NO and physiology/pathophysiology. To this end, we seek to create tools for the fluorescent imaging of NO in vivo. We have adapted an existing small molecule-based sensor for more biologically relevant applications by including it within a polymeric film. We have also developed turn-on fluorescent sensors for NO based on conjugated polymers, which demonstrated good selectivity and sensitivity for this analyte. In addition, we have prepared a related sensor that will detect nitroxyl (HNO) but not NO. These systems demonstrate the versatility and value of the conjugated polymer scaffold for sensing applications. Many targets of the diatomic radical NO contain redox active units, such as transition metals or thiolate ligands. To gain insight into how NO might regulate biological processes by interacting with these redox active species, we have initiated a fundamental study of the reactivity of NO with transition metal thiolate model complexes. Our explorations in this field have yielded unique nickel and cobalt nitrosyl species with atypical electronic and structural parameters. These studies have suggested intermediates for the more biologically relevant iron nitrosyl complexes that have not yet been observed may exist. Furthermore, the NO chemistry of these small molecule nickel and cobalt thiolate complexes may guide future biological investigations into the regulation of nickel and cobalt metalloproteins by NO.
Andrew Gregory Tennyson.
Ph.D.
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Mills, Ross Jack. "Autoantibodies in ILD : detection and association of anti-Hsp72 IgG complexes in IPF." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/29615.
Full textAbstract:
Background Idiopathic pulmonary fibrosis (IPF) is one of a number of interstitial lung diseases (ILDs) that result in extensive and chronic pulmonary fibrosis. In IPF pathology, immunological dysfunction has been identified as a contributing factor to the ongoing fibrotic process, implicating cells and mechanisms of both the innate and humoral immune response. Due to the complex and diverse range of cells and mediators involved in IPF, the pathology is still poorly understood. Evidence of complement activation through the classical pathway in IPF lungs implies a role for IgG in the pathology. The active IgG in IPF may be autoreactive in nature, as IgG that target antigens of alveolar epithelial cells have been. Two autoantibodies in IPF, anti-periplakin IgG and anti-Hsp72 IgG, have been associated with poorer prognoses in IPF patients. The association of anti-Hsp72 IgG with IPF patient outcomes has not been validated and little work has been done to study the underlying mechanisms of autoantibodies in IPF pathogenesis. Hypothesis Anti-Hsp72 IgG is associated with poorer outcomes in IPF, and may induce alveolar macrophages to exhibit a pro-fibrotic phenotype. Aims The aims were to: Optimise an ELISA for anti-Hsp72 IgG detection and determine any association of anti-Hsp72 IgG with IPF patient outcomes Determine the location of anti-Hsp72 IgG producing cells and detect if Hsp72-IgG complexes are present in IPF patients’ lungs Explore a potential underlying pro-fibrotic mechanism through which anti-Hps72 IgG modulates macrophage function. Results The presence of anti-Hsp72 IgG was determined in ILD patient and healthy control bronchoalveolar lavage fluid (BALf) and serum. A novel anti-Hsp72 IgG ELISA was developed and optimised and then compared against a commercial anti-Hsp72 IgGAM ELISA which became available during the PhD. Progression in IPF was defined by a decrease of ≥10% vital capacity (VC) over twelve months. Serum anti-Hsp72 IgG(AM) did not associate with changes in VC over 12 months. In contrast, BALf anti-Hsp72 IgG(AM) concentrations were elevated in IPF non-progressors. Patients with high BALf anti-Hsp72 IgGAM, had improved survival compared patient with low anti-Hsp72 IgGAM (adjusted HR 0.39, 95% CI 0.16-0.92; p=0.032) In contrast there was no association between anti-Hsp72 IgG and survival. Detection of anti-Hsp72 IgG subtypes in the serum and BALf of IPF patients revealed no significant difference in anti-Hsp72 IgG subtype detection levels between progressors and non-progressors. BALf anti-Hsp72 IgG1 levels were associated with a significantly lower rate of decline in VC over twelve months than patients with no detectable anti-Hsp72 IgG1. The presence of Hsp72-IgG complexes was confirmed by detection in purified IgG from IPF patient BALf. Immuno-histological detection of C4d deposition in the lungs of IPF patients coincided in areas of Hsp72 expression in alveolar epithelium. Summary These findings do not validate serum and-Hsp72 IgG as a biomarker for IPF. They support a role for anti-Hsp72 IgG in IPF, but associate with decreased rates of lung function decline and increased patient survival. Data also suggests that the decreased rate of decline may be related to specific anti-Hsp72 IgG subtype expression. The immune-histological data further suggests that anti-Hsp72 IgG may be targeting Hsp72 expressed by lung epithelium. Therefore these findings support a role for immunological dysfunction in IPF, but further work is required to determine the underlying mechanism.
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Milenko, Čanković. "Širina QRS kompleksa kao elektrokardiografski prediktor reperfuzije nakon primarne perkutane koronarne intervencije i veličine akutnog infarkta miokarda sa ST elevacijom." Phd thesis, Univerzitet u Novom Sadu, Medicinski fakultet u Novom Sadu, 2020. https://www.cris.uns.ac.rs/record.jsf?recordId=112570&source=NDLTD&language=en.
Full textAbstract:
Ishemijska bolest srca najčešće nastaje kao posledica razvoja aterosklerotskih promena na koronarnim krvnim sudovima koji dovode do suženja lumena i posledičnog pada protoka arterijske krvi u području vaskularizacije. Akutni oblik koronarne bolesti koji zahteva hitnu primenu reperfuzione terapije je ST elevirani infarkt miokarda. EKG ima veliki značaj u postavljanju dijagnoze ali i u proceni uspešnosti same reperfuzije. Širina QRS kompleksa jedan je od EKG parametara čija dinamika promena može ukazati na uspešnost pPKI i veličinu infarktne zone. Evaluacija širine QRS kompleksa kao prediktora veličine infarkta miokarda i reperfuzije nakon pPKI kod pacijenata sa STEMI. Ispitivanje je sprovedeno kao prospektivna, opservaciona klinička studija na Klinici za kardiologiju, Instituta za kardiovaskularne bolesti Vojvodine u periodu od januara 2016. do decembra 2018. godine. U isptivanje je uključeno 200 pacijenata sa STEMI kod kojih je urađena pPKI. Na osnovu dužine trajanja tegoba formirane su dve grupe od po 100 pacijenata. Grupa A kod kojih je totalno ishemijsko vreme bilo <6h i grupa B kod kojih je totalno ishemijsko vreme između 6 i 12h. . Sprovedeno je EKG praćenje radi procene širine QRS kompleksa intrahospitalno (pre procedure, odmah nakon pPKI kao i posle 1h i 72h) i na dve vizite ambulantno tokom šestomesečnog praćenja (nakon mesec dana i šest meseci). Ehokardiografija je urađena kod svih pacijenata intrahospitalno i na šestomesečnom ambulantnom pregledu. Širine QRS kompleksa su korelirane sa rezultatima interventne procedure procenjene TIMI protokom i TMPG, dinamikom kardiospecifičnih enzima i ehokardiografskim nalazima. U istraživanje je uključeno 71% muškaraca i 29% žena, prosečna starost uzorka iznosila je 60.6±11.39. Dužina trajanja tegoba značajno se razlikovala između grupa. U grupi A tegobe su trajale prosečno 120 minuta (90-180), dok su u grupi B trajale 420 minuta (360-600) (p<0.0005). DTB nije se značajno razlikovao, 42 minuta (31-54.5) u odnosu na 40.5 minuta (34.5-55) (p=0.818). Prosečna širina QRS kompeksa na EKG-u pre pPKI nije se značajno razlikovala između grupa, 100 msec (90-110) u odnosu na 100 msec (93-110) (p=0.308). Nakon reperfuzije uočena je značajna razlika u širini QRS kompleksa između grupa na svim intrahospitalnim kao i EKG-ima načinjenim tokom perioda praćenja. QRS kompleks je širi kod pacijenata iz grupe B (p<0.0005). Pacijenti iz grupe A koji su imali prohodnu infarktnu arteriju sa TIMI 3 protokom pre implantacije stenta imali su značajno uži QRS kompleks na incijilanom EKG-u u odnosu na pacijente kod kojih je IRA bila sub/okludirana sa TIMI protokom ≤2 (p=0.001). U grupi B prohodna infarktna arterija sa TIMI 3 protokom nije značajno uticala na širinu QRS kompleksa na inicijalnom EKG-u (p=0.144). Na EKG-ima nakon procedure QRS kompleks bio je značajno širi kod pacijenata kod kojih je TIMI protok ≤2, ali samo za grupu pacijenata koja se javila unutar 6h od početka tegoba (p=0.001). QRS kompleks kod pacijenata koji su se javili nakon 6h od početka tegoba jeste bio uži, ali bez statistički značajne razlike (p=0.336). Pearsonovim testom registrovano je postojanje negativne korelacije širine QRS kompleksa i istisne frakcije leve komore, ali i pozitivne korelacije sa WMSI i indeksiranim end sistolnim i end dijastolnim volumenom. ROC analizom pokazano je da ukoliko je QRS kompleks širi od 89 msec nakon mesec dana, 8.5 puta je veći rizik od snižene EF na šestomesečnoj kontroli (p<0.0005, AUC=0.808, cut-off=89msec.). ROC analiza pokazala je i da ukoliko je QRS kompleks širi od 99msec 1h nakon procedure, 5 puta je veći rizik od pojave MACE (p<0.0005, AUC=0.744, cut-off=99msec). Izvedena su dva matematička modela zasnovana na širini QRS kompleksa koja vrše predikciju snižene EF i pojave MACE tokom perioda praćenja. Širina QRS kompleksa je pokazatelj reperfuzije kod pacijenata sa STEMI kod kojih se načini revaskularizacija unutar 6h od nastanka tegoba. Širina QRS kompleksa mesec dana nakon STEMI predstavlja nezavisni prediktor snižene EF. Proširenje preko 89msec 8.5 povećava rizik od snižene EF. Širina QRS kompleksa jedan sat nakon pPKI predstavlja nezavisni prediktor za MACE. Proširenje preko 99msec 5 puta povećava rizik od neželjenog kardiološkog događaja. Izvedena su dva matematička modela koja koriste širinu QRS kompleksa i sa visokom preciznošću vrše predikciju MACE-a, odnosno snižene EF nakon šest meseci. Ischemic heart disease most commonly occurs as a result of the atherosclerotic changes in the coronary vessels that lead to the narrowing of the lumen and consequent fall in arterial blood flow in the vascularization area. An acute form of coronary artery disease requiring immediate reperfusion therapy is ST-elevation myocardial infarction. The ECG is of great importance not only in making the diagnosis but also in evaluating the success of the reperfusion itself. The duration of the QRS complex is one of the ECG parameters whose change in dynamics can indicate the success of pPCI as well as the size of the infarct zone. Evaluation of the width of the QRS complex as a predictor of myocardial infarction size and reperfusion after pPCI in patients with STEMI. The study was conducted as a prospective, observational clinical study at the Cardiology Clinic of the Institute of Cardiovascular Diseases of Vojvodina between January 2016 and December 2018. The study included 200 patients with STEMI in whom pPCI was performed. Based on the length of discomforts two groups with 100 patients were formed. Group A had a total ischemic time <6h and the total ischemic time in group B was between 6-12h. To assess the duration of the QRS complex, the ECG monitoring was performed intrahospital (before the procedure, immediately after pPCI as well as 1h and 72h after the procedure) and on two outpatient visits during the six-month follow-up period (after one month and six months). Echocardiography was performed in all patients intrahospital and at a six-month outpatient visit. The duration of the QRS complex correlated with the results of the interventional procedure that was evaluated by the TIMI flow and TMPG, the dynamics of cardiospecific enzymes and echocardiography findings. The survey included 71% of men and 29% of women with an average age of 60.6 ± 11.39. The duration of the discomforts varied significantly between the groups. In group A the discomforts lasted 120 minutes in an average (90-180), while they lasted 420 minutes in group B (360-600) (p <0.0005). DTB did not differ significantly, 42 minutes (31-54.5) versus 40.5 minutes (34.5-55) (p = 0.818). The average duration of the QRS complex on the ECG before pPCI did not differ significantly between the groups, 100 msec (90-110) versus 100 msec (93-110) (p = 0.308). After the reperfusion, a significant difference in the duration of the QRS complex was observed between the groups at all intrahospital ECGs and the ECGs performed during the follow-up period. The QRS complex was broader in group B patients (p <0.0005). Group A patients who had a patent infarct artery with TIMI 3 flow before the stent implantation had a significantly narrower QRS complex on the initial ECG compared to the patients whose IRA was sub / occluded with TIMI flow ≤2 (p = 0.001). In group B, the patent infarct artery with TIMI 3 flow did not significantly affect the duration of the QRS complex at the initial ECG. (p = 0.144). At the post-procedural ECGs the QRS complex was significantly broader in patients with TIMI flow ≤2, but only in the group of patients who arrived within 6 h from the onset of discomforts (p = 0.001). The QRS complex in patients who arrived 6 h after the onset of discomforts was narrower but without statistically significant difference (p = 0.336). The Pearson test registered the existence of a negative correlation of the QRS complex width and the left ventricular ejection fraction, but also a positive correlation with the WMSI and index end-systolic and end-diastolic volumes. The ROC analysis showed that if the QRS complex was wider than 89 msec after one month, there was an 8.5 times higher risk of decreased EF at the six-month control examination (p <0.0005, AUC = 0.808, cut-off = 89msec.). The ROC analysis also showed that if the QRS complex was wider than 99msec 1h after the procedure, there was a 5 times higher risk of MACE (p <0.0005, AUC = 0.744, cut-off = 99msec). Two mathematical models based on the width of the QRS complex were derived that predicted the lowered EF and the occurrence of MACE during the monitored period. The width of the QRS complex is an indicator of reperfusion in patients with STEMI who undergo revascularization within 6 hours from the onset of discomforts. The width of the QRS complex one month after STEMI is an independent predictor of decreased EF. Broadening over 89msec increases the risk of lowered EF for 8.5 times. The width of the QRS complex one hour after pPCI represents an independent predictor of MACE. Broadening over 99msec increases the risk of an adverse cardiac event 5 times. Two mathematical models have derived that use the width of the QRS complex and predict MACE with high precision as well as reduced EF after six months.
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ARNOLD, MARC. "Etude de la genotoxicite de matrices complexes par la detection des adduits a l'adn." Université Louis Pasteur (Strasbourg) (1971-2008), 2000. http://www.theses.fr/2000STR13215.
Full textAbstract:
L'objectif de ce travail etait d'evaluer la phytogenotoxicite de matrices contaminees artificiellement ou provenant de sites pollues par l'etude de l'induction de modifications primaires de l'adn (ou adduits a l'adn) de ble et de lentille exposes a ces matrices en utilisant la technique de postmarquage au 3 2p. - dans le cas de matrices complexes contaminees artificiellement par des metaux lourds (sol si), un melange de trichlorophenol, pentachlorophenol et phenanthrene (sol sii) ou de benzo(a)pyrene (sol sii'), les resultats sont en faveur d'une genotoxicite des sols si et sii' pour le ble, a l'inverse du sol sii qui n'est pas genotoxique pour cette espece. De plus, aucune matrice ne s'est revelee genotoxique pour la lentille cultivee sur ces matrices. - dans le cas de matrices provenant de friches industrielles (sols siii et siv) de contaminations mixtes (metaux lourds, et composes organiques) ou de stations d'epuration urbaine (boue b1) ou de papeterie (boue b4), les resultats obtenus avec le ble se sont reveles negatifs aussi bien dans les experimentations en fonction de la concentration en matrice que dans les experimentations cinetiques. Par contre, les sols siii et siv utilises comme litiere pour des rats se sont reveles genotoxiques pour les poumons dans les essais avec le sol siii et pour les poumons et le foie avec le sol siv. Avec le modele vegetal, ble et/ou lentille cultives directement sur les matrices des resultats negatifs ont donc ete obtenus alors que des essais (test d'ames, tests micronoyaux) effectues sur des lixiviats par d'autres groupes sur les memes matrices ont montre que ces lixiviats etaient mutagenes et genotoxiques et que les rats exposes aux litieres des sols siii et siv presentaient des modifications
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Moragues, Pons María Esperanza. "Transition metal complexes for chromo-fluorogenic detection of carbon monoxide in environmental and biomedical applications." Doctoral thesis, Universitat Politècnica de València, 2015. http://hdl.handle.net/10251/48453.
Full textAbstract:
La presente tesis doctoral titulada “Complejos metálicos de transición para la
detección cromo-fluorogénica de monóxido de carbono en aplicaciones
medioambientales y biomédicas” se basa en la utilización de los principios de la
Química de la Coordinación para el diseño y desarrollo de nuevos compuestos
químicos capaces de detectar monóxido de carbono en aire mediante cambios de
color y/o de fluorescencia.
La primera familia de sondas colorimétricas que se presenta en el capítulo 3
está basada en unos complejos dinucleares de rodio hexacoordinados con
ligandos trifenilfosfina y distintos ácidos carboxílicos. Primeramente, se expone el
trabajo desarrollado con el complejo A de fórmula
[Rh2(C6H4PPh2)2(O2CCH3)2]·(HO2CCH3)2 capaz de detectar selectivamente y con alta
sensibilidad CO tanto en disolución como en aire. En presencia de CO se produce
un cambio de color de morado a amarillo, debido a la coordinación del CO en las
posiciones axiales del complejo.
A continuación se amplia el trabajo con una colección de cinco complejos de
rodio (II) B-F adsorbidos en gel de sílice y se estudia su uso como sondas para la
detección de CO en aire mediante cambios de color visibles a simple vista.
En tercer lugar, se procede a depositar los complejos en papel de celulosa para
facilitar su aplicación en la detección práctica de CO. Se elige el complejo D
[Rh2[(C6H4)P(C6H5)2]2(O2CCF3)2]· (CF3CO2H)2 como el más sensible a CO en este
nuevo soporte y se inserta dentro de un sistema opto-electrónico capaz de
cuantificar el CO presente en el aire; mediante la transducción del cambio de
color del complejo en una señal eléctrica, y esta señal en un valor de
concentración de CO determinado.
Finalmente, teniendo en cuenta el papel del CO como agente terapéutico y
aprovechando que la coordinación de CO en los complejos de rodio presentados
es reversible; se seleccionan los dos complejos dicarbonílicos con cinéticas de
liberación de CO en disolución más lentas A·(CO)2 y F·(CO)2 de fórmulas
[Rh2[(C6H4)P(C6H5)2]2(O2CCH3)2]·(CO)2 y [Rh2[(m-CH3C6H3)P(m-
CH3C6H4)2]2(O2CCH3)2]·(CO)2) como posibles moléculas liberadoras de CO (CO-RMs)
a utilizar en estudios sobre inhibición de agentes indicadores de inflamación
celular (ver capítulo 4).
En la segunda parte de esta tesis doctoral se ha preparado una colección de
vinil complejos de rutenio y de osmio G-K funcionalizados con grupos dadores de
electrones (pireno, tolueno y benceno) y con un grupo aceptor de electrones
(2,1,3-benzotiadiazol (BTD)). Estos complejos son coloreados, ya que presentan
una banda de transferencia de carga. En presencia de CO se produce el
desplazamiento del BTD con el consiguiente cambio de color (ver capítulo 5).
En primer lugar, para posibilitar la detección fluorogénica de CO, se ha
preparado el complejo G mediante el anclaje del fluoróforo pirenilvinilo como
ligando dador de electrones del complejo de rutenio (II). En presencia de CO y
mediante el desplazamiento del BTD se consigue un aumento de fluorescencia
observable incluso a simple vista.
Para concluir la segunda parte de la tesis se han sintetizado cuatro complejos
más, H-K, dos de rutenio y dos de osmio; que han sido utilizados también para
detectar CO en aire. Para la preparación de estas sondas también se ha utilizado
gel de sílice como soporte. En presencia de CO se produce el desplazamiento del
BTD (colorante) y los complejos metálicos cambian de color, permitiendo así la
semicuantificación del CO en los rangos de concentración en que el CO es
altamente tóxico incluso para exposiciones cortas.Moragues Pons, ME. (2014). Transition metal complexes for chromo-fluorogenic detection of carbon monoxide in environmental and biomedical applications [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48453
TESIS
Premiado
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Martin, Lynwill Garth. "Electrochemistry and electrophoresis of mercury cysteine and ditizone complexes." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/1742.
Full textAbstract:
Thesis (MSc (Chemistry and Polymer Science))--Stellenbosch University, 2008.There are various mercury species in the environment and their toxicity and availability relies on their chemical form and oxidation states. Inorganic and organic mercury is found to co-exist in water and body tissue of some organisms. Among them inorganic mercury has a lower toxicity than the organic mercury. Methyl mercury (CH3Hg+) is the most toxic species found in the environment because it can enter the food chain accumulating and contaminating humans. Hence the total mercury concentration does not reflect the important information and thus the needs for the development of methods for the simultaneously separating and determination of mercury species. A study of the electrochemistry of mercury and organo mercury complexes with cysteine and dithizone indicated the formation of stable complexes, which can be utilized for the determination of the species in environmental matrices. Cyclic voltammetry is used to determine the electrochemical properties of the complexes. A technique based on capillary electrophoresis and amperometric detection (CE-AD) has been developed for the speciation of mercury. This technique has the capability to detect mercury species that are electrochemically active. Using capillary electrophoresis in combination with electrochemical detection makes speciation of the complexes possible at lower than normal concentrations. For CE-AD the detection limits were 0.005 μg/L for Hg2+ and 0.4 μg/L for MeHg+. These detection sensitivities are attractive for environmental monitoring.
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Skřížala, Martin. "Využití neuronových sítí v klasifikaci srdečních onemocnění." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217210.
Full textAbstract:
This thesis discusses the design and the utilization of the artificial neural networks as ECG classifiers and the detectors of heart diseases in ECG signal especially myocardial ischaemia. The changes of ST-T complexes are the important indicator of ischaemia in ECG signal. Different types of ischaemia are expressed particularly by depression or elevation of ST segments and changes of T wave. The first part of this thesis is orientated towards the theoretical knowledges and describes changes in the ECG signal rising close to different types of ischaemia. The second part deals with to the ECG signal pre-processing for the classification by neural network, filtration, QRS detection, ST-T detection, principal component analysis. In the last part there is described design of detector of myocardial ischaemia based on artificial neural networks with utilisation of two types of neural networks back – propagation and self-organizing map and the results of used algorithms. The appendix contains detailed description of each neural networks, description of the programme for classification of ECG signals by ANN and description of functions of programme. The programme was developed in Matlab R2007b.
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Liao, Jing-Piin. "Investigation of Copper-Natural Ligand Complexes by RP-HPLC Photodiode Array UV-VIS and Fluorescence Detection." Thesis, University of North Texas, 1992. https://digital.library.unt.edu/ark:/67531/metadc332502/.
Full textAbstract:
In this study, reversed phase HPLC with dual UV photodiode (PDA) and fluorescence (FL) detection were used to investigate copper complexes with fulvic, caffeic, vanillic, salicylic, and adipic acids. Application of the RE method provided valuable information on the retention behavior and spectral characteristics of FA and model compounds. Even though the method was only applicable to VA, the use of the PDA detector allowed the UV-V is scanning of the separated peaks. This allowed the comparison between the UV-Vis spectra of uncomplexed species. The overall results provide an experimental framework for validation of the proposed Cu-humate interaction models.
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Akhimie, Regina Nicole. "Investigation of Rh2(II,II) complexes for applications in photochemotherapy and mismatch detection." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1511892689942643.
Full text
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Beamish, Eric. "Precise Size Control and Noise Reduction of Solid-state Nanopores for the Detection of DNA-protein Complexes." Thesis, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23569.
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Over the past decade, solid-state nanopores have emerged as a versatile tool for the detection and characterization of single molecules, showing great promise in the field of personalized medicine as diagnostic and genotyping platforms. While solid-state nanopores offer increased durability and functionality over a wider range of experimental conditions compared to their biological counterparts, reliable fabrication of low-noise solid-state nanopores remains a challenge. In this thesis, a methodology for treating nanopores using high electric fields in an automated fashion by applying short (0.1-2 s) pulses of 6-10 V is presented which drastically improves the yield of nanopores that can be used for molecular recognition studies. In particular, this technique allows for sub-nanometer control over nanopore size under experimental conditions, facilitates complete wetting of nanopores, reduces noise by up to three orders of magnitude and rejuvenates used pores for further experimentation. This improvement in fabrication yield (over 90%) ultimately makes nanopore-based sensing more efficient, cost-effective and accessible.
Tuning size using high electric fields facilitates nanopore fabrication and improves functionality for single-molecule experiments. Here, the use of nanopores for the detection of DNA-protein complexes is examined. As proof-of-concept, neutravidin bound to double-stranded DNA is used as a model complex. The creation of the DNA-neutravidin complex using polymerase chain reaction with biotinylated primers and subsequent purification and multiplex creation is discussed. Finally, an outlook for extending this scheme for the identification of proteins in a sample based on translocation signatures is presented which could be implemented in a portable lab-on-a-chip device for the rapid detection of disease biomarkers.
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Yakoubi, Zied. "Détection et évaluation des communautés dans les réseaux complexes." Thesis, Paris 13, 2014. http://www.theses.fr/2014PA132045/document.
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Dans le contexte des réseaux complexes, cette thèse s’inscrit dans deux axes : (1) Méthodologiede la détection de communautés et (2) Evaluation de la qualité des algorithmes de détection de communautés. Dans le premier axe, nous nous intéressons en particulier aux approches fondées sur les Leaders (sommets autour desquels s’agrègent les communautés). Premièrement, nous proposons un enrichissement de la méthodologie LICOD qui permet d’évaluer les différentes stratégies des algorithmes fondés sur les leaders, en intégrant différentes mesures dans toutes les étapes de l’algorithme. Deuxièmement, nous proposons une extension de LICOD, appelée it-LICOD. Cette extension introduit une étape d’auto-validation de l’ensemble des leaders. Les résultats expérimentaux de it-LICOD sur les réseaux réels et artificiels sont bons par rapport à LICOD et compétitifs par rapport aux autres méthodes. Troisièmement, nous proposons une mesure de centralité semi-locale, appelée TopoCent, pour remédier au problème de la non-pertinence des mesures locales et de la complexité de calcul élevée des mesures globales. Nous montrons expérimentalement que LICOD est souvent plus performant avec TopoCent qu’avec les autres mesures de centralité. Dans le deuxième axe, nous proposons deux méthodes orientées-tâche, CLE et PLE, afin d’évaluer les algorithmes de détection de communautés. Nous supposons que la qualité de la solution des algorithmes peut être estimée en les confrontant à d’autres tâches que la détection de communautés en elle-même. Dans la méthode CLE nous utilisons comme tâche la classification non-supervisée et les algorithmes sont évalués sur des graphes générés à partir des jeux de données numériques. On bénéficie dans ce cas de la disponibilité de la vérité de terrain (les regroupements) de plusieurs jeux de données numériques. En ce qui concerne la méthode PLE, la qualité des algorithmes est mesurée par rapport à leurs contributions dans une tâche de prévision de liens. L’expérimentation des méthodes CLE et PLE donne de nouveaux éclairages sur les performances des algorithmes de détection de communautésIn this thesis we focus, on one hand, on community detection in complex networks, and on the other hand, on the evaluation of community detection algorithms. In the first axis, we are particularly interested in Leaders driven community detection algorithms. First, we propose an enrichment of LICOD : a framework for building different leaders-driven algorithms. We instantiate different implementations of the provided hotspots. Second, we propose an extension of LICOD, we call it-LICOD. This extension introduces a self-validation step of all identified leaders. Experimental results of it-LICOD on real and artificial networks show that it outperform the initial LICOD approach. Obtained results are also competitive with those of other state-of-the art methods. Thirdly, we propose a semi-local centrality measure, called TopoCent, that address the problem of the irrelevance of local measures and high computational complexity of globalmeasures. We experimentally show that LICOD is often more efficient with TopoCent than with the other classical centrality measures. In the second axis, we propose two task-based community evaluation methods : CLE and PLE. We examine he hypothesis that the quality of community detection algorithms can be estimated by comparing obtained results in the context of other relevent tasks. The CLE approach, we use a data clustering task as a reference. The PLE method apply a link prediction task. We show that the experimentation of CLE and PLE methods gives new insights into the performance of community detection algorithms
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Tidriri, Khaoula. "Fusion de décisions dédiée à la surveillance des systèmes complexes." Thesis, Angers, 2018. http://www.theses.fr/2018ANGE0014/document.
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Le niveau de complexité croissant des systèmes et les exigences de performances et de sûreté de fonctionnement qui leur sont associées ont induit la nécessité de développer de nouvelles approches de surveillance. Les travaux de cette thèse portent sur la surveillance des systèmes complexes, notamment la détection, le diagnostic et le pronostic de défauts, avec une méthodologie basée sur la fusion de décisions. L’objectif principal est de proposer une approche générique de fusion de diverses méthodes de surveillance, dont la performance serait meilleure que celles des méthodes individuelles la composant. Pour cela, nous avons proposé une nouvelle démarche de fusion de décisions, basée sur la théorie Bayésienne. Cette démarche s’appuie sur une déduction théorique des paramètres du Réseau Bayésien en fonction des objectifs de performance à atteindre en surveillance. Le développement conduit à un problème multi-objectif sous contraintes, résolu par une approche lexicographique. La première étape se déroule hors-ligne et consiste à définir les objectifs de performance à respecter afin d’améliorer les performances globales du système. Les paramètres du réseau Bayésien permettant de respecter ces objectifs sont ensuite déduits de façon théorique. Enfin, le réseau Bayésien paramétré est utilisé en ligne afin de tester les performances de la fusion de décisions. Cette méthodologie est adaptée et appliquée d’une part à la détection et au diagnostic, et d’autre part au pronostic. Les performances sont évaluées en termes de taux de diagnostic de défauts (FDR) et taux de fausses alarmes (FAR) pour l’étape de détection et de diagnostic, et en durée de fonctionnement avant la défaillance du système (RUL) pour le pronosticNowadays, systems are becoming more and more complex and require new effective methods for their supervision. This latter comprises a monitoring phase that aims to improve the system’s performances and ensure a safety production for humans and materials. This thesis work deals with fault detection, diagnosis and prognosis, with a methodology based on decisions fusion. The main issue concerns the integration of different decisions emanating from individual monitoring methods in order to obtain more reliable results. The methodology is based on a theoretical learning of the Bayesian network parameters, according to monitoring objectives to be reached. The development leads to a multi-objective problem under constraints, which is solved with a lexicographic approach. The first step is offline and consists of defining the objectives to be achieved in order to improve the overall performance of the system. The Bayesian network parameters respecting these objectives are then deduced theoretically. Finally, the parametrized Bayesian network is used online to test the decision fusion performances. These performances are evaluated in terms of Fault Diagnostic Rate (FDR) and False Alarm Rate (FAR) for the detection and diagnosis stage, and in terms of Remaining Useful Life (RUL) for the prognosis
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Davy, Axel. "Modélisation de fonds complexes statiques et en mouvement : application à la détection d'événements rares dans les séries d'images." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLN048/document.
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{La première partie de cette thèse est dédiée à la modélisation d'images ou de vidéos considérés comme des fonds sur lesquels on s'attache à détecter des anomalies. Notre analyse de la littérature de la détection d'anomalie sur une seule image nous a fait identifier cinq différentes familles d'hypothèses structurelles sur le fond. Nous proposons de nouveaux algorithmes pour les problèmes de détection d'anomalie sur seule image, de détection de petites cibles sur un fond en mouvement, de détection de changements sur des images satellitaires SAR (Synthetic Aperture Radar) et de détection de nuages dans des séquences d'images de satellite optique.Dans une seconde partie, nous étudions deux autres applications de la modélisation de fond. Pour le débruitage vidéo, nous cherchons pour chaque patch de la vidéo, des patchs similaires le long de la séquence vidéo, et fournissons à un réseau de neurones convolutif les pixels centraux de ces patchs. Le modèle de fond est caché dans les poids du réseau de neurones. Cette méthode s'avère être la plus performante des méthodes par réseau de neurones comparées. Nous étudions également la synthèse de texture à partir d'un exemple. Dans ce problème, des échantillons de texture doivent être générés à partir d'un seul exemple servant de référence. Notre étude distingue les familles d'algorithmes en fonction du type de modèle adopté. Dans le cas des méthodes par réseau de neurones, nous proposons une amélioration corrigeant les artefacts de bord.Dans une troisième partie, nous proposons des implémentations temps-réel GPU de l'interpolation B-spline et de plusieurs algorithmes de débruitage d'images et de vidéo: NL-means, BM3D et VBM3D. La rapidité des implémentations proposées permet leur utilisation dans des scénarios temps-réel, et elles sont en cours de transfert vers l'industrieThe first part of this thesis is dedicated to the modeling of image or video backgrounds, applied to anomaly detection. In the case of anomaly detection on a single image, our analysis leads us to find five different families of structural assumptions on the background. We propose new algorithms for single-image anomaly detection, small target detection on moving background, change detection on satellite SAR (Synthetic Aperture Radar) images and cloud detection on a sequence of satellite optical images.In the second part, we study two further applications of background modeling. To perform video denoising we search, for every video patch, similar patches in the video sequence, and feed their central pixels to a convolutional neural network (CNN). The background model in this case is hidden in the CNN weights. In our experiments, the proposed method is the best performing of the compared CNN-based methods. We also study exemplar-based texture synthesis. In this problem texture samples have to be generated based on only one reference sample. Our survey classifies the families of algorithms for this task according to their model assumptions. In addition, we propose improvements to fix the border behavior issues that we pointed out in several deep learning based methods.In the third part, we propose real-time GPU implementations for B-spline interpolation and for several image and video denoising algorithms: NL-means, BM3D and VBM3D. The speed of the proposed implementations enables their use in real-time scenarios, and they are currently being transitioned to industry
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Saunders, Gregory David. "The sequestration and detection of aqueous uranium using a novel network polymer." Thesis, University of York, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323692.
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Warnke, Molly Melissa. "Enantiomeric separations of natural compounds and metal complexes and the detection of anions using positive mode electrospray ionization mass spectrometry." [Ames, Iowa : Iowa State University], 2008.
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Joshi, Ubisha. "Characterization of Ionic Liquid As a Charge Carrier for the Detection of Neutral Organometallic Complexes Using Electrospray Ionization Mass Spectrometry." Thesis, University of North Texas, 2012. https://digital.library.unt.edu/ark:/67531/metadc149615/.
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A novel application of ionic liquid as a charge carrier for the analysis and detection of neutral organometallic complexes using a mass spectrometer has been presented. The mass spectrometer detects only charged compounds which raise a difficulty in analyzing a neutral molecule that lacks a basic site to associate with charge. Therefore, an effective way of providing charge has always been an area of keen interest in the field of mass spectrometry. Ionic liquids have a very fascinating property of forming a cation-? interaction with other molecules to give a charged complex. In order to take advantage of this, it is important to know the geometric structure of the complex. Advanced methodologies like hydrogen-deuterium exchange and computational calculations have been used assisting in better understanding of the structure of the ionic liquid complexes.