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Rossi, Matteo. "Non invasive hydrogeophysical techniques for vadose zone hydrological characterization." Doctoral thesis, Università degli studi di Padova, 2010. http://hdl.handle.net/11577/3427485.
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Hydrogeophysics is a discipline that emerged and had a great development in the last two decades. The aim of this discipline is the subsurface hydrological and hydrogeological characterization via non-invasive geophysical techniques. Conventional sampling techniques, for characterizing or monitoring the shallow subsurface, are typically sparsely distributed or acquired at an inappropriate scale. Non-invasive geophysical datasets can provide more dense 2D/3D information. The present work focused on the hydrological characterization of the vadose zone, as it is a challenging issue that may be more deeply and extended understood.
The dependence of the geophysical response on changes in soil moisture content, e.g. via changes in electrical resistivity or dielectric properties, is the key mechanism that permits the use of non-invasive techniques to monitor the vadose zone in time-lapse mode, i.e. via repeated measurements over time. The use of these techniques in different configurations in the shallow and deep vadose zones can provide high-resolution images of hydrogeological structures and a detailed assessment of dynamic processes in the subsurface environment. The data from non-invasive techniques can subsequently be used to calibrate physical-mathematical models of water flow in the unsaturated zone. The understanding of fluid-dynamics is the key to all hydrologically-controlled environmental problems. The hydrogeophysical approach is based on links that can be established between geophysical quantities and hydrological variables, such as water content and solute concentration, generally in the form of empirical or semi-empirical petrophysical relationships.
The classical hydrogeophysical approach in hydraulic parameters evaluation starts from the measured geophysical data to estimate the hydrological state, albeit careful is need at this step: essential is the knowledge achievable from field data and the relative accuracy in the physical translation. Anyway this is the starting point for the hydrological simulation. Subsequently the hydrological modelled parameters may be compared and evaluated with the hydrological quantities obtained from geophysics through the petrophysical relationships. This approach can lead to erroneous parameter inference, if the spatial resolution of the geophysical techniques is not taking into account.
A different approach can be proceed, to overcome this issue. In spite of translating geophysical parameters in hydrological quantities, the comparison may be done directly on the not-inverted geophysical data. The geophysical surveys can be simulated with a forward model, starting from the hydrological modelled properties distribution and applying the petrophysical relationship to reconstruct the geophysical spatially-distributed parameters. At this point geophysical measured and simulated data can be compared, with the aim of calibrate and validate the hydrological model under examination. This second approach, not requiring geophysical inversions, is able to overcome artefacts deriving from the inversion procedure; but the resolution of the surveys must be considered, because an hydrological state should not be reproduced from geophysical methodologies, even if the two datasets, both simulated and measured, are in a perfect fitting.
The work is divided in two complementary parts. The first part is centred on the hydrological quasi-steady state characterization from cross-hole radar measurements. In many studies cross-borehole zero offset profiles (ZOP) are used to infer subsoil moisture content, which are a key topic in hydrological modelling and consequently in hydraulic parameters estimation. The principal aim of this work is to have a more complete view of how boreholes GPR ZOP measurements are informative of the subsoil geometry and distribution of relative permittivity. This is essential in moisture content estimation, uncertainty quantification and in the initial setting of parameters necessary for starting an hydrological model. For this purpose three different ZOP datasets are analysed: a synthetic dataset and two field-measured datasets.
The second part of the work is the hydrogeophysical inversion of a tracer test in the vadose zone, conducted at the Hatfield site (near Doncaster, UK). The path of a tracer in vadose zone may be masked from the variations of the physical status surrounding the dispersive plume; this could lead to erroneous interpretations of the evolving plume. The load of the new water, that moves under gravitational forces, produces the raising of the degree of saturation in the media just below the plume. This incidental effect could significantly contribute to geophysical signals and hydrological characterizations. The aim of this study is the recognition and distinction of the paths of the new injected fluid from the groundwater, already present in the system and activated from pressure variations, in a sort of “piston” effect. The discrimination between the new percolating water and the old pushed-down water is a key issue in aquifer vulnerability and soil pollution migrations, which can affect the vadose zone. In this second part the hydrogeophysical inversion is conducted: the simulated hydrological quantities are used to obtain a geophysical forward model of ZOP surveys, that should be compared with measured ZOP soundings. An estimation of the goodness of the hydrological model is then possible. A particle tracking code is then run to detect the exact evolution of the tracer plume in the subsurface. A comparison with the results from the inverted geophysical datasets is able to discriminate the tracer fluid from the old water of the system and to individuate where the geophysical imaging could be deceptive and misleading.
The present work is an example of the hydrogeophysical inversion methods, where great emphasis is focused on the characterization of the hydraulic state preceding the tracer injection test. Anyway the system must be stressed under artificial hydraulic states to force the parameters estimation and to limit the range of probable hydrological models.L’idrogeofisica è una disciplina che è emersa ed ha avuto un importante sviluppo nelle ultime due decadi. Lo scopo di questa disciplina è la caratterizzazione idrologica ed idrogeologica del sottosuolo attraverso tecniche geofisiche non invasive. Le tecniche di campionamento convenzionali sono di norma spazialmente distribuite ed acquisite ad una scala impropria. Le tecniche geofisiche invece permettono indagini spazialmente più fitte in 2D o 3D. Il presente lavoro si focalizza sulla caratterizzazione idrologica della zona vadosa. I dati ottenuti dalle tecniche geofisiche possono essere utilizzati per calibrare modelli fisico matematici del flusso nella zona del non-saturo. Tale approccio idrogeofisico è basato su relazioni petrofisiche che legano le quantità geofisiche con le variabili idrologiche. Il classico approccio idrogeofisico parte dalle misure geofisiche per ottenere una stima di parametri idrologici, che a loro volta vengono impiegati in modelli idraulici in grado di fornire ulteriori proprietà del sistema idraulico del sottosuolo. I modelli idrologici vengono successivamente validati e calibrati con i risultati delle inversioni geofisiche in time-lapse. Questo approccio prevede l’inversione del dato geofisico, metodo che può portare ad immagini del sottosuolo che contengono artefatti e che non tengono conto della risoluzione della tecnica applicata. Un approccio differente prevede che ai parametri stimati dai modelli idraulici siano applicate le relazioni petrofisiche, al fine di tradurre le quantità idrologiche in quantità geofisiche. A questo punto la simulazione di modelli geofisici diretti permette un confronto immediato con i dati misurati, senza l’ausilio dell’inversione geofisica. Il presente lavoro è suddiviso in due parti. La prima parte è centrata sulla caratterizzazione idrologica dello stato stazionario iniziale attraverso misure radar (GPR). Lo scopo principale del lavoro è quello di quantificare quanto le misure GPR a zero offset profiling (ZOP) siano informative delle geometrie del sottosuolo e delle relative condizioni di contenuto idraulico dei materiali. Questo lavoro è essenziale per ottenere una stima del contenuto idrico del sottosuolo e della relativa incertezza che ne deriva, poiché tali stime sono il punto di partenza delle simulazioni idrauliche. La seconda parte del lavoro è focalizzata sulla inversione idrogeofisica di un test con tracciante salino condotto ad Hatfield (UK). L’approccio idrogeofisico adottato è quello di simulare misure geofisiche direttamente dalla distribuzione dei parametri idrologici calcolati, per ottenere una calibrazione di quelle quantità idrologiche scopo della metodologia applicata. La ricostruzione dell’evoluzione di un plume iniettato nella zona vadosa è interessante ai fini di identificare i possibili percorsi di un contaminante nel sottosuolo. A tale scopo un codice di particle tracking è stato applicato ai risultati dell’inversione idrologica. Il codice di partcle tracking è in grado di distinguere i percorsi dell’acqua iniettata dall’acqua già presente nel sistema e movimentata del cambiamento di pressione in atto, ‘effetto pistone’. Le inversioni delle misure geofisiche non permettono di distinguere il fluido tracciante dai cambiamenti del contenuto idrico dei materiali adiacenti al plume iniettato.
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Agnoletto, Federica Claudia <1995>. "Setting up of a non-invasive methodology for painting surfaces characterization." Master's Degree Thesis, Università Ca' Foscari Venezia, 2020. http://hdl.handle.net/10579/16955.
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The following thesis work is focussed on the application of non-invasive spectroscopic methodologies (External Reflection Infrared, Raman and Fiber Optics Reflectance) on painting surfaces, in order to perform a characterization of the present materials. The analyses are applied on a collection of more than 100 paint samples, first created in 1992, consisting in traditional pigments dispersed in different media. The collection has already been analysed by invasive techniques, and the collected data will be compared with the new acquisitions. The aim of the study is to achieve sufficient information regarding the preliminary selection of the best analytical technique, according to the sample nature. For this reason, the application of statistical tools (such as Principal Component Analysis) would also be performed, leading to the integration of all the data and the creation of a research “model”.
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Linssen, Franciscus Maria Joannes. "Non-invasive arterial wall tissue characterization development and evaluation of narrowband ultrasound techniques /." [Maastricht : Maastricht : Rijksuniversiteit Limburg] ; University Library, Maastricht University [Host], 1992. http://arno.unimaas.nl/show.cgi?fid=6208.
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Kuska, Matheus [Verfasser]. "Hyperspectral Imaging for Non-Invasive Characterization of Barley Resistances to Powdery Mildew / Matheus Kuska." Bonn : Universitäts- und Landesbibliothek Bonn, 2017. http://d-nb.info/1172813019/34.
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Bassani, Molinas Maria de los Milagros. "Transient transfection of HEK293 cells in suspension process characterization and optimization by applying invasive nucleotide and non-invasive electronic nose technology /." [S.l. : s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=976524295.
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Coursey, Derya Calhan. "Respiratory mechanics of flow limitation and characterization of resistance measurements with a non-invasive device." College Park, Md.: University of Maryland, 2009. http://hdl.handle.net/1903/9272.
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Thesis (Ph.D.) -- University of Maryland, College Park, 2009.Thesis research directed by: Dept. of Biological Resources Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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FELIGIOTTI, MARA. "Damage characterization in artworks: finite element method simulation and experimental validation by non invasive techniques." Doctoral thesis, Università Politecnica delle Marche, 2008. http://hdl.handle.net/11566/242580.
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Willis, Richard Lance. "Non-invasive characterization of microvoided polymers under controlled static pressure and temperature using laser doppler vibrometry." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/17248.
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Kempe, Sabine [Verfasser], K. [Akademischer Betreuer] Mäder, J. [Akademischer Betreuer] Siepmann, and J. [Akademischer Betreuer] Kreßler. "Non-invasive characterization of in situ forming implants / Sabine Kempe. Betreuer: K. Mäder ; J. Siepmann ; J. Kreßler." Halle, Saale : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2012. http://d-nb.info/1025303407/34.
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Muchingami, Innocent I. "NON-INVASIVE CHARACTERIZATION OF UNSATURATED ZONE TRANSPORT IN DRY COAL ASH DUMPS: A CASE STUDY OF TUTUKA, SOUTH AFRICA." University of the Western Cape, 2013. http://hdl.handle.net/11394/4268.
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Doctor ScientiaeThe management of the large volumes of solid wastes produced as coal combustion residue is of particular concern due to the presence of leachable metals and salts which may constitute a long term environmental risk and potential contamination of both surface and groundwater systems of the surrounding environment. In order to implement an efficient monitoring scheme and to assess the impact of the ash dump on the hydrologic system, a thorough knowledge on the migration of solutes fluxes in dry ash dumps as well as the controls on the transport of these solutes to the underlying groundwater system is required. The conventional methods which have been widely used for such applications are centred on extracting and analysing several samples from observation wells are drilled on the dump. This has however created a potentially hazardous situation as the installation of monitoring wells may result in the creation of new fluid pathways and results in further migration of leachates. Nevertheless, non–invasive characterization has often been useful in the determination of subsurface hydraulic properties and is a key step towards the solution of real-life problems in hydrology, hydrogeology and soil science. In contaminant transport non-invasive methods have often proved to be an efficient tool as compared to traditional drilling and sampling techniques which in most cases results in the creation of preferential flow paths and do not allow for the space and time resolution needed for the monitoring of hydrological and environmental processes. In this context, this study seeks to develop a generic conceptual model for the ash dump through the use of non-invasive geophysical techniques and numerical modelling techniques at the Tutuka Ash dump, Mpumalanga South Africa. Changes in electrical resistivity were used correlate changes in moisture contents during moisture and salt leachate ingression in ash dumps with a sufficient accuracy. A determination of the suitability of Archie‘s law to describe the relationship between electrical resistivity and solute transport ash medium was achieved through empirical laboratory experiments. Electrical resistivity tomography was then used as an appropriate tool for the elucidation of potential flow paths and brine dispersion in the ash dump. The flow rates through the ash dump were estimated by considering the rate of brine injection and the distance travelled by the brine plume over the time spanned in time lapse infiltration experiments. Additional geophysical profiles managed to show the lithostratigraphy of underlying hydro-geology, thereby ensuring that the knowledge of the geology can be established without the application of any intrusive methods. To ensure that development of the conceptual model of the unsaturated zone transport of the ash dump was developed with sufficient accuracy, numerical models were also used to describe solute transport in the vadose zone. The HYDRUS2D numerical package was used simulate the flux dynamics within the unsaturated zone of the coal ash medium, so as to develop a conceptual understanding of water flow and salt transport through the unsaturated zone of the coal ash medium. The results from the study suggested a conceptual solute transport model that consists of a two layers. The upper layer represented the unsaturated zone of the ash dump which was the source of any potential contaminant transport that could be of concern. The lower layer describe the underlying the subsurface environment to the ash dump which include the soil zone, the shallow aquifer and the deep fractured rock aquifer. To enable this conceptualisation, results from the numerical simulations and geophysical interpretations of the electrical resistivity profiles were the critical components for optimising the site-specific subsurface water flow and solute transport processes, as well as producing the most acceptable conceptualisation of the ash dump system that could be used in hazard assessment and mitigation against potential groundwater pollution. The conceptual models developed in this study proposed an explanation on impact of the ash dump to the hydro-geologic and the eco-hydrologic environment by proposing a scenario of contamination of the underling ash dump and the existing. In this regard, the study managed to provide important scenarios that may be necessary during mitigation procedures for both the ash dump and the wetland. Key words: non-invasive, coal ash, time lapse, electrical resistivity tomography, numerical models, HYDRUS2D, conceptual model.
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Mugabe, Clement. "Development and characterization of intravesical mucoadhesive nanoparticulate formulations of paclitaxel and docetaxel for postoperative chemotherapy in non-muscle-invasive bladder cancer." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/37727.
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The present work describes the development, in vitro and in vivo evaluation of mucoadhesive nanoparticulate formulations of paclitaxel (PTX) and docetaxel (DTX) for intravesical bladder cancer therapy.
The nanoparticles developed for PTX and DTX delivery consisted of hyperbranched polyglycerol (HPG), which were hydrophobically derivatized with alkyl chains (C₈/₁₀) in the core to allow drug loading and were further derivatized with methoxy polyethylene glycol (MePEG) and primary amine groups in the shell (HPG-C₈/₁₀-MePEG-NH₂) to increase their mucoadhesiveness. Human urothelial carcinoma cell lines were treated with various concentrations of PTX and DTX formulations in vitro. Mice with established KU7-luc tumors were intravesically treated with various concentrations of PTX and DTX formulations or control vehicles. Drug uptake was conducted using LC/MS/MS and tumor microenvironment and uptake of rhodamine labeled HPGs was assessed by immunohistochemistry-based tumor mapping and fluorescence microscopy. The effects of HPG nanoparticles on the urinary bladder wall were studied on isolated porcine bladder tissues as well as in live mouse bladders. To investigate the toxicity and tolerability, histopathological evaluations were preformed following a single intravesical instillation with empty HPG nanoparticles in healthy female nude mice.
In vitro, PTX and DTX loaded HPG nanoparticles were found to have equivalent cytotoxicities as their commercial formulations of Taxol® and Taxotere®, respectively. The surface modification of HPG-C₈/₁₀-MePEG with amine groups resulted in highly positive charged nanoparticles (HPG-C₈/₁₀-MePEG-NH₂) with improved mucoadhesive properties. A single intravesical instillation with DTX loaded HPG-C₈/₁₀-MePEG-NH₂ at a lower dose significantly inhibited tumor growth and increased drug uptake in mouse bladder tissues. HPG-C₈/₁₀-MePEG-NH₂ nanoparticles were found to significantly increase the uptake of DTX in both isolated pig bladder as well as in live mouse bladder tissues likely resulting from changes to the urothelial barrier function and morphology through opening of tight junctions and exfoliation of the superficial umbrella cells. Our preliminary studies suggest that this exfoliation was triggered by an apoptosis mechanism followed by a rapid recovery of the urothelium within 24 h post-instillation.
Overall, our data show promising in vivo anti-tumor efficacy and provide preclinical proof-of-principle for intravesical application of these nanoparticulate formulations in the treatment of non-muscle-invasive bladder cancer.
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Kumar, Vidhya. "Towards Multiorgan Characterization of Cardiometabolic Health and Disease." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1523624759693821.
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Ahmed, Manal Bayomi Mahmoud. "The susceptibility of primordial germ cells to malignant transformation and isolation and characterization of members of a new gene family differentially expressed in invasive and non-invasive immortalized male germ cells." [S.l.] : [s.n.], 2001. http://webdoc.sub.gwdg.de/diss/2002/ahmed/ahmed.pdf.
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Pantoja, Morales Carlos Roberto. "Hepatopancreatic parvovirus of penaeid shrimp (HPV): Partial cloning and genome characterization, in situ hybridizationat the ultrastructural level, geographic diversity and non-invasive detection." Diss., The University of Arizona, 1999. http://hdl.handle.net/10150/284064.
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The genome of a Korean isolate of Hepatopancreatic parvovirus (HPV) was partially cloned, sequenced and characterized. Random PCR amplification of viral DNA was combined with conventional cloning methods to generate three clones named HPV8 (2,136 bp insert), HPV3 (1,560 bp insert), and CP1139 (413 bp insert). DNA sequencing demonstrated overlapping regions between HPV8 and HPV3 and between HPV3 and CPII39. The combined sequence of these three clones encompass approximately 3,350 bp of the total 5,000 bp estimated for the HPV genome. A large open reading frame (1,692 bp) was found within clones HPV3/CPII39 encoding a polypeptide of 549 residues (∼60 kDa) whose amino terminus shows 100% homology with the first 12 residues sequenced from an apparently single 54 kDa (by SDS-PAGE) structural protein found in a Korean isolate of HPV. Two new gene probes EC.592 (592 bp) and EC.350 (350 bp) were developed by PCR amplification of previously constructed HPV (Korean) clones and labeled with DIG11-dUTP. These probes recognize different regions of the HPV genome. The specificity of both probes was confirmed by in situ hybridization using HPV-infected Penaeus chinensis (Korean) as a positive control and specific-pathogen free P. vannamei and IHHNV-infected P. stylirostris, as negative controls. Both probes were used in in situ hybridization to compare their reaction to HPV-type lesions detected by conventional H&E histology in 7 species of HPV-infected shrimp, and one of freshwater prawn, from 13 countries. The results of this comparison strongly suggest the existence of genomic differences among these geographic isolates. A post-embedding in situ hybridization assay at the electron microscope level was developed to detect HPV nucleic acids on HPV-infected hepatopancreata from P. chinensis and P. monodon . Hybridized probe (EC.592) was detected with an anti-DIG sheep antibody conjugated to 10 nm gold particles and subsequent silver enhancement. Hybridization signal was observed within HPV-infected hepatopancreatic cells, which was specifically located within intranuclear viral inclusions, cytoplasm, microvillous border, and associated to necrotic debris within the lumen of hepatopancreatic tubules. A non-destructive method, based on the PCR, was developed to detect HPV by examination of crude fecal samples from HPV-infected shrimp.
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Hundshammer, Christian [Verfasser], Steffen J. [Akademischer Betreuer] Glaser, Steffen J. [Gutachter] Glaser, and Axel [Gutachter] Haase. "Multimodal and Non-Invasive Imaging Techniques for a Multiparametric Characterization of Tumor Biology / Christian Hundshammer ; Gutachter: Steffen J. Glaser, Axel Haase ; Betreuer: Steffen J. Glaser." München : Universitätsbibliothek der TU München, 2019. http://d-nb.info/1181326346/34.
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Moritz, Franco [Verfasser], Philippe [Akademischer Betreuer] Schmitt-Kopplin, and Michael [Akademischer Betreuer] Rychlik. "Deep Metabotyping of exhaled breath condensate (EBC) – characterization of surrogate markers for systemic metabolism and non-invasive diagnostics in Diabetes / Franco Moritz. Gutachter: Philippe Schmitt-Kopplin ; Michael Rychlik. Betreuer: Philippe Schmitt-Kopplin." München : Universitätsbibliothek der TU München, 2014. http://d-nb.info/1070372439/34.
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Riedel, Simone Stefanie [Verfasser], and Andreas [Akademischer Betreuer] Beilhack. "Characterization of the fluorescence protein FP635 for in vivo imaging and establishment of a murine multiple myeloma model for non-invasive imaging of disease progression and response to therapy / Simone Stefanie Riedel. Betreuer: Andreas Beilhack." Würzburg : Universitätsbibliothek der Universität Würzburg, 2013. http://d-nb.info/1035370921/34.
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Lenz, Michael. "Neuartige Ultraschallmeßverfahren unter Nutzung von Schallfeldinformationen." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-135656.
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Die vorliegende Arbeit untersucht, wie die genaue Kenntnis der Sende- und Empfangsschallfelder eines Ultraschallwandlers zur Entwicklung neuer Meßverfahren genutzt werden kann. Insbesondere werden dargestellt: - ein neuartiges, nichtscannendes Verfahren zur Bestimmung der Krümmung eines Reflektors, basierend auf der Analyse der Wellenfrontkrümmung reflektierter Schallfelder - ein neuartiges, nichtinvasives Verfahren zur Bestimmung der Schallgeschwindigkeit in einer Flüssigkeit durch Auswertung der Echosignale von im Ausbreitungsmedium vorhandenen Streupartikeln und - ein Verfahren zur Wandlercharakterisierung durch Messungen in Fluiden mit Streupartikeln, sowie verschiedene Zuordnungen von Schallfeldmerkmalen zu spezifischen Eigenschaften eines Ultraschallwandlers. Im Zusammenspiel von Simulation und Experiment konnten die Funktionstüchtigkeit aller Meßverfahren nachgewiesen und vielversprechende innovative Ansätze für zukünftige Entwicklungen angeregt werden: 1. Das nichtscannende Verfahren zur Krümmungsmessung erlaubt bei guter Justage eine Krümmungsbestimmung von Reflektoren mit Radien zwischen 6 und 11 mm mit einer Unsicherheit von ungefähr 0,5 mm. In Kombination mit herkömmlichen scannenden Verfahren bietet es Ansätze zur präzisen Größenbestimmung von Fehlern in der zerstörungsfreien Prüfung. 2. Das Verfahren zur nichtinvasiven Schallgeschwindigkeitsmessung erlaubt eine Bestimmung von Schallgeschwindigkeiten mit einer statistischen Meßunsicherheit von 0,1 %. Mögliche Weiterentwicklungen zur Messung der Schallgeschwindigkeit mit örtlicher Auflösung und zur Gewinnung neuer Diagnosemöglichkeiten in Metallurgie (nichtinvasive Charakterisierung von Mischungsvorgängen) und Biomedizintechnik (nichtinvasive Temperaturmessung in Körpergewebe zur Überwachung der Hyperthermiebehandlung, Gewebecharakterisierung) werden erläutert. Aus verschiedenen bekannten sowie einem neuartigen, leicht anwendbaren Meßverfahren werden neue Schlüsse gezogen a) zur Bestimmung der akustisch effektiven Elementgröße von Wandlerelementen mittels Schallfeldmessungen, b) zur Qualitätssicherung im Hinblick auf Schallkopfasymmetrien und c) zur Verbesserung von SchallfeldsimulationenThe current thesis explores how the precise knowledge of the sending and receiving sound fields of an ultrasonic transducer can contribute to the development of novel measuring techniques. Emphasis is placed on: - a novel, non-scanning method for the determination of the curvature radius of a spherical reflector, based on the analysis of the wave front curvature of the reflected sound field, - a novel non-invasive method for sound velocity measurements in fluids using the echo signals from scattering particles, and - novel conclusions on how to use well-known sound field measurement methods for transducer characterisation, as well as an introduction to a novel easy-to-use method for transducer characterisation exploiting the echo signals from scattering particles. Proof of concept is shown for all methods by simulation and measurement, and different promising improvements for further techniques are suggested: - The non-scanning method for curvature measurements makes it possible to determine reflector radii between 6 and 11 mm with an uncertainty of about 0.5 mm, provided that there is a good reflector alignment. In combination with conventional methods, a novel approach for the determination of the size of discontinuities in non-destructive testing is outlined. - The method for non-invasive sound velocity measurements allows the determination of sound velocity in homogeneous fluids with a statistical uncertainty of 0.1 %. Future improvements are suggested to allow sound velocity measurements with local resolution, which enables novel approaches for metallurgy (non-invasive characterisation of mixing processes) and biomedical engineering (non-invasive temperature control for hyperthermia treatment, tissue characterisation). - New conclusions are drawn based on well-established and a novel easy-to-implement measurement method regarding a) the determination of the acoustically effective element size of transducer elements, b) transducer asymmetries, thereby improving quality control, and c) the improvement of sound field simulations
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Huber, Adrian Thomas. "Multi-organ non-invasive tissue characterization of fibrosis, adipose tissue, edema and inflammation with magnetic resonance (MR) imaging : applications to myocardium, skeletal muscle and liver interactions Cardiac MR strain: a noninvasive biomarker of fibro-fatty remodeling of the left atrial myocardium Comparison of MR T1 and T2 mapping parameters to characterize myocardial and skeletal muscle involvement in systemic Idiopathic Inflammatory Myopathy (IIM) Non-invasive differentiation of acute viral myocarditis and idiopathic inflammatory myopathy with cardiac involvement using magnetic resonance imaging T1 and T2 mapping CT predicts liver fibrosis: Prospective evaluation of morphology- and attenuationbased quantitative scores in routine portal venous abdominal scans." Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS135.
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Cette thèse réalise une preuve de concept pour quantifier la déformation de l’oreillette gauche (OG) en IRM, ainsi que la relaxométrie IRM dans le myocarde, dans les muscles squelettiques et dans le foie. Grâce à l’interaction entre radiologues et ingénieurs, deux logiciels différents ont été développés, appliqués et validés pour l'analyse de la déformation myocardique multi-chambre et pour la cartographie quantitative du T1 multi-organes. La première publication a montré une forte corrélation de la déformation de l’OG, avec le degré de remplacement fibro-graisseux en histologie. Ce biomarqueur d'imagerie fonctionnelle est prometteur, puisque le remodelage structurel du myocarde est un substrat morphologique connu du dysfonctionnement électro-physiologique et de la fibrillation atriale. La deuxième publication a démontré l'influence de la composition et de la vascularisation de différents tissus sur les paramètres cartographiques T1. ΔT1 (prise de contraste musculaire relative) et EHF (prise de contraste musculaire normalisée par la prise de contraste dans le sang) ont été introduits comme alternatives simples au volume extracellulaire (ECV). Dans la troisième publication, les paramètres de relaxométrie appliqués aux muscles squelettiques ont permis une discrimination entre patients avec myocardite aiguë et patients avec des myosites systémiques. La quatrième publication a introduit le T1 du foie pour quantifier l’insuffisance cardiaque chez des patients avec des cardiomyopathies idiopathiques dilatées, montrant de meilleures performances que les paramètres fonctionnels établis tels que les volumes, la fraction d'éjection ou la déformation myocardiqueThis thesis provides a proof of concept for MR atrial strain, as well as MR relaxometry in the myocardium, in skeletal muscles and in the liver. Thanks to a close interaction between radiologist and software engineers, two different softwares were developed, applied and validated: one for multiorgan T1 mapping in the myocardium, skeletal muscle and liver, another one for cardiac four-chamber strain analysis and volumetry. The first publication showed a strong correlation of LA strain with the degree of fibro-fatty replacement in histology. Such functional imaging biomarker in combination with LA volumetry could help to guide clinical decisions, since myocardial structural remodeling is a known morphologic substrate of LA dysfunction, atrial fibrillation and adverse outcome. In the second publication, MR relaxometry parameters applied to the myocardium and skeletal muscles in IIM patients and healthy volunteers were used as a model to demonstrate influences of different tissue composition and vascularization on T1 mapping parameters. ΔT1 and EHF were introduced as simple alternatives to ECV in highly vascularized tissues such as the myocardium. In the third publication, MR relaxometry parameters applied to the skeletal muscls allowed for an accurate discrimination of AVM and IIM with cardiac involvement. However, when applied to the myocardium, parametric mapping did not separate between the two groups. The fourth publication introduced native T1 of the liver an easily accessible and accurate non-invasive imaging associate of congestive HF in IDCM patients with better performance than established functional parameters such as LV volumes, ejection fraction or strain
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Ganesh, Karistha. "Molecular characterization of non-groupable Neisseria meningitidis causing invasive disease in South Africa." Thesis, 2017. https://hdl.handle.net/10539/24741.
Full textAbstract:
The University of the Witwatersrand,
Faculty of Health Sciences
In fulfilment of the requirements for the degree of
Master of Science in Medicine. 27 October 2017.Background The meningococcal capsule is an important virulence determinant. Unencapsulated meningococci lacking capsule biosynthesis genes and containing the capsule null locus (cnl) are predominantly non-pathogenic. Rare cases of invasive meningococcal disease caused by cnl isolates belonging to sequence types (ST) and clonal complexes (cc) ST-845 (cc845), ST-198 (cc198), ST-192 (cc192) and ST-53 (cc53) have been documented. The clinical significance of these isolates however remains unclear. We identified four invasive cnl meningococci through laboratory-based surveillance in South Africa from 2003 through 2013, which we aimed to characterize using whole genome data. Results One isolate [NG: P1.7-2,30: F1-2: ST-53 (cc53)] contained cnl allele 12, and caused empyema in an adult male with bronchiectasis from tuberculosis, diabetes mellitus and a smoking history. Three isolates were NG: P1.18-11,42-2: FΔ: ST-192 (cc192) and contained cnl allele 2. One patient was an adolescent male with meningitis. The remaining two isolates were from recurrent disease episodes (eight months apart) in a male child with deficiency of the sixth complement component, and with the exception of two single nucleotide polymorphisms, contained identical core genomes. The ST-53 (cc53) isolate possessed alleles for NHBA peptide 191 and fHbp variant 2; whilst the ST-192 (cc192) isolates contained NHBA peptide 704 and fHbp variant 3. All four isolates lacked nadA. Comparison of the South African genomes to 65 additional cnl genomes on the PubMLST Neisseria database (http://pubmlst.org/neisseria/), determined that most putative virulence genes could be found in both invasive and carriage phenotypes. Conclusions Although rare, invasive disease by cnl meningococci may be associated with host immunodeficiency and such patients may benefit from protein-based meningococcal vaccines.
LG2018
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Porée, Jonathan. "Évaluation de la biomécanique cardiovasculaire par élastographie ultrasonore non-invasive." Thèse, 2016. http://hdl.handle.net/1866/18571.
Full textAbstract:
L’élastographie est une technique d’imagerie qui vise à cartographier in vivo les propriétés mécaniques des tissus biologiques dans le but de fournir des informations diagnostiques additionnelles. Depuis son introduction en imagerie ultrasonore dans les années 1990, l’élastographie a trouvé de nombreuses applications. Cette modalité a notamment été utilisée pour l’étude du sein, du foie, de la prostate et des artères par imagerie ultrasonore, par résonance magnétique ou en tomographie par cohérence optique. Dans le contexte des maladies cardiovasculaires, cette modalité a un fort potentiel diagnostique puisque l’athérosclérose modifie la structure des tissus biologiques et leurs propriétés mécaniques bien avant l’apparition de tout symptôme. Quelle que soit la modalité d’imagerie utilisée, l’élastographie repose sur : l’excitation mécanique du tissu (statique ou dynamique), la mesure de déplacements et de déformations induites, et l’inversion qui permet de recouvrir les propriétés mécaniques des tissus sous-jacents. Cette thèse présente un ensemble de travaux d’élastographie dédiés à l’évaluation des tissus de l’appareil cardiovasculaire. Elle est scindée en deux parties. La première partie intitulée « Élastographie vasculaire » s’intéresse aux pathologies affectant les artères périphériques. La seconde, intitulée « Élastographie cardiaque », s’adresse aux pathologies du muscle cardiaque. Dans le contexte vasculaire, l’athérosclérose modifie la physiologie de la paroi artérielle et, de ce fait, ses propriétés biomécaniques. La première partie de cette thèse a pour objectif principal le développement d’un outil de segmentation et de caractérisation mécanique des composantes tissulaires (coeur lipidique, tissus fibreux et inclusions calciques) de la paroi artérielle, en imagerie ultrasonore non invasive, afin de prédire la vulnérabilité des plaques. Dans une première étude (Chapitre 5), nous présentons un nouvel estimateur de déformations, associé à de l’imagerie ultrarapide par ondes planes. Cette nouvelle méthode d’imagerie permet d’augmenter les performances de l’élastographie non invasive. Dans la continuité de cette étude, on propose une nouvelle méthode d’inversion mécanique dédiée à l’identification et à la quantification des propriétés mécaniques des tissus de la paroi (Chapitre 6). Ces deux méthodes sont validées in silico et in vitro sur des fantômes d’artères en polymère. Dans le contexte cardiaque, les ischémies et les infarctus causés par l’athérosclérose altèrent la contractilité du myocarde et, de ce fait, sa capacité à pomper le sang dans le corps (fonction myocardique). En échocardiographie conventionnelle, on évalue généralement la fonction myocardique en analysant la dynamique des mouvements ventriculaires (vitesses et déformations du myocarde). L’abscence de contraintes physiologiques agissant sur le myocarde (contrairement à la pression sanguine qui contraint la paroi vasculaire) ne permet pas de résoudre le problème inverse et de retrouver les propriétés mécaniques du tissu. Le terme d’élastographie fait donc ici référence à l’évaluation de la dynamique des mouvements et des déformations et non à l’évaluation des propriétés mécanique du tissu. La seconde partie de cette thèse a pour principal objectif le développement de nouveaux outils d’imagerie ultrarapide permettant une meilleure évaluation de la dynamique du myocarde. Dans une première étude (Chapitre 7), nous proposons une nouvelle approche d’échocardiographie ultrarapide et de haute résolution, par ondes divergentes, couplée à de l'imagerie Doppler tissulaire. Cette combinaison, validée in vitro et in vivo, permet d’optimiser le contraste des images mode B ainsi que l’estimation des vitesses Doppler tissulaires. Dans la continuité de cette première étude, nous proposons une nouvelle méthode d’imagerie des vecteurs de vitesses tissulaires (Chapitre 8). Cette approche, validée in vitro et in vivo, associe les informations de vitesses Doppler tissulaires et le mode B ultrarapide de l’étude précédente pour estimer l’ensemble du champ des vitesses 2D à l’intérieur du myocarde.Elastography is an imaging technique that aims to map the in vivo mechanical properties of biological tissues in order to provide additional diagnostic information. Since its introduction in ultrasound imaging in the 1990s, elastography has found many applications. This method has been used for the study of the breast, liver, prostate and arteries by ultrasound imaging, magnetic resonance imaging (MRI) or optical coherence tomography (OCT). In the context of cardiovascular diseases (CVD), this modality has a high diagnostic potential as atherosclerosis, a common pathology causing cardiovascular diseases, changes the structure of biological tissues and their mechanical properties well before any symptoms appear. Whatever the imaging modality, elastography is based on: the mechanical excitation of the tissue (static or dynamic), the measurement of induced displacements and strains, and the inverse problem allowing the quantification of the mechanical properties of underlying tissues. This thesis presents a series of works in elastography for the evaluation of cardiovascular tissues. It is divided into two parts. The first part, entitled « Vascular elastography » focuses on diseases affecting peripheral arteries. The second, entitled « Cardiac elastography » targets heart muscle pathologies. In the vascular context, atherosclerosis changes the physiology of the arterial wall and thereby its biomechanical properties. The main objective of the first part of this thesis is to develop a tool that enables the segmentation and the mechanical characterization of tissues (necrotic core, fibrous tissues and calcium inclusions) in the vascular wall of the peripheral arteries, to predict the vulnerability of plaques. In a first study (Chapter 5), we propose a new strain estimator, associated with ultrafast plane wave imaging. This new imaging technique can increase the performance of the noninvasive elastography. Building on this first study, we propose a new inverse problem method dedicated to the identification and quantification of the mechanical properties of the vascular wall tissues (Chapter 6). These two methods are validated in silico and in vitro on polymer phantom mimicking arteries. In the cardiac context, myocardial infarctions and ischemia caused by atherosclerosis alter myocardial contractility. In conventional echocardiography, the myocardial function is generally evaluated by analyzing the dynamics of ventricular motions (myocardial velocities and deformations). The abscence of physiological stress acting on the myocardium (as opposed to the blood pressure which acts the vascular wall) do not allow the solving the inverse problem and to find the mechanical properties of the fabric. Elastography thus here refers to the assessment of motion dynamics and deformations and not to the evaluation of mechanical properties of the tissue. The main objective of the second part of this thesis is to develop new ultrafast imaging tools for a better evaluation of the myocardial dynamics. In a first study (Chapter 7), we propose a new approach for ultrafast and high-resolution echocardiography using diverging waves and tissue Doppler. This combination, validated in vitro and in vivo, optimize the contrast in B-mode images and the estimation of myocardial velocities with tissue Doppler. Building on this study, we propose a new velocity vector imaging method (Chapter 8). This approach combines tissue Doppler and ultrafast B-mode of the previous study to estimate 2D velocity fields within the myocardium. This original method was validated in vitro and in vivo on six healthy volunteers.
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Tseng, Chan-Chia, and 曾展嘉. "Characterization of a Hydrodynamic Well for Non-invasive Trapping of Single Cells in a Microfluidic Device." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/87355138115299863154.
Full textAbstract:
碩士臺灣大學
應用力學研究所
98
Single cell trapping for measuring different cellular response is important for a variety of applications including rare cell studies, minimal residual disease, and improved understanding of basic cell biology. The purpose of this thesis is to provide an integrated noninvasive microfluidic platform which can trap single cells for subsequent studies. The proposed platform utilizes Lorentz force to drive an oscillating microplate generating localized low pressure region, or a hydrodynamic well, in order to trap single cells along the edge of the microplate. Cells are levitated by a time-mean low pressure due to nonlinear flow streaming, fixing cells in a spatial region against background flow. Fabrication of the device involved conventional photolithographic soft lithographic processes, with two masks for the microstructure and one for the microchannel. Different sizes of polystyrene particles were used to verify the wide range of single cell trapping feasible. Jurkat cells in suspended state were used to test the selectivity of hydrodynamic well and the ability to sort different size. Dimensional analysis was used to characterize the physics of the flow filed by commercial simulation software (COMSOL Multiphysics®). Results show the trapping force is in the range of dozens of pico-Newton with only 3 to 5 Vpp of driving voltage. Ability to select different size of cell shows the capability to trap different cell sizes with proper conditions. This microfluidic device provides a robust approach to trap single cells or multiple isolated cells effectively for cellular analysis.
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Nabais, Paula Sofia Fonseca. "Spectroscopic characterization of natural dyes by their non-invasive identification on pre-Columbian codices: the Maya yellow." Master's thesis, 2014. http://hdl.handle.net/10362/13591.
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Mesoamerican cultures had a strong tradition of written and pictorial manuscripts, called the codices. In studies already performed it was found the use of Maya Blue, made from a mixture of indigo and a clay called palygorskite, forming an incredibly stable material where the dye is trapped inside the nanotubes of the clay, after heating. However, a bigger challenge lies in the study of the yellows used, for these civilizations might have used this clay-dye mixture to produce their yellow colorants.
As a first step, it was possible to provide identification, by non-invasive methods, of two colorants (a flavonoid and a carotenoid). While the flavonoid absorbed between 368-379 nm, the carotenoid would absorb around 455 nm. A temperature study also conducted allowed to set 140ºC as the desirable temperature to heat the samples without degrading them. FT-IR, conventional Raman and SERS allowed us to understand the existence of a reaction between the dyes and the clays (palygorskite and kaolinite), however it is difficult to understand it in a molecular point of view.
As a second step, five species of Mexican dyes were selected on the basis of historical sources. The Maya yellow samples were produced adapting the recipe proposed by Reyes-Valerio, supporting the yellow dyes extracted from the dried plants on the clays, with addition of water, and then heated at 140ºC. It was found that the addition of water in palygorskite would increase the pH, hence deprotonating the molecules having a clear negative effect in the color.
A second recipe was developed, without the addition of water; however, it was found that the use of water based binders would still alter the color of the samples with palygorskite. In this case, kaolinite without heating yield better results as a Maya yellow hybrid.
It was found that the Maya chemistry might not have been the same for all the colors. The Mesoamericans might have found that different dyes could work better to their desires if matched with different clays.
It was noticeable that for a clear distinction between flavonoids and carotenoids the reflectance and emission studies suffice, but when clay is added, Raman techniques will perform better. For this reason, conventional Raman and SERS were employed in order to create a database for the Mesoamerican dyestuffs for a future identification.
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Madeira, Mariana Simões. "Analysis of non-invasive imaging data using self-organising maps for characterization of tumour physiological and biochemical properties." Master's thesis, 2012. http://hdl.handle.net/10316/25129.
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Nos dias de hoje a informática aplicada à investigação em cancro é de grande importância. Neste trabalho, técnicas de aprendizagem não supervisionada e supervisionada foram aplicadas a dados de [18F]Fluorotimidina – Tomografia por Emissão de Positrões ([18F]FLT-PET).
Como aprendizagem supervisionada usámos um filtro chamado Filtro Cinético Espacial (KSF) desenvolvido no Imperial College que é baseado na captação do radiofármaco ([18F]FLT) que difere de tecido para tecido. É um filtro capaz de separar tumor e vértebra dos restantes tecidos. Contudo, quando aplicado a imagens de ratinhos implantados com linhas celulares de cancro de HCT116, mesmo quando curvas de actividade ao longo do tempo do próprio ratinho foram usadas como modelo, este não conseguiu obter os mesmos resultados que obtivemos na análise de dados de um paciente com cancro no pâncreas com metastases no fígado onde o filtro foi capaz de distinguir o tumor dos órgãos circundantes. Esta análise pretende ser usada para detectar resposta precoce depois de um ciclo de tratamentos.
Como aprendizagem não supervisionada usámos Self-Organizing Maps (SOM). Aplicámos este algoritmo em dados de [18F]FLT-PET de ratinhos. Primeiro aplicámos SOM na análise de dados de HCT116. O objectivo foi alcançado com sucesso, uma vez que os mapas finais conseguiram diferenciar imagens de pré das de pós tratamento. Numa segunda aplicação, usámos SOM com dados de ratinhos implatados com linhas celulares de A2780, SJSA, SN40R2 e HT29 para ver se este conseguia distinguir e classificar os tumores. Conseguimos apenas distinguir SJSA das restantes linhas celulares. Em ambos os estudos, dados de input de SOM eram voxels obtidos de regiões de interesse: tumor, músculo, bexiga, coração e rim. Características dos mapas finais são os padrões de clustering dos voxels de cada tecido. No resultado final, o SOM conseguiu os seguintes clusters: tumor, músculo e bexiga num cluster e coração e rins noutro mais difuso. Quando aplicámos SOM apenas a ROIs sobre os tumores, a separação entre diferentes tumores foi apenas parcialmente conseguida.
Numa terceira aplicação usámos este método de classificação nos dados da paciente, para ver se este conseguia distinguir entre pré o pós tratamento, no sentido de poder avaliar se o paciente estaria a responder ou não ao tratamento. Descobrimos que o
x
algoritmo era capaz efectuar esta tarefa. Aqui o algoritmo agrupou fígado, tumor, vértebra e rins e colocou o coração noutro cluster.
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Wang, C. "Portable Hyperspectral Sensor: A New Application in Cultural Heritage Conservation." Doctoral thesis, 2019. http://hdl.handle.net/2158/1154772.
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A portable hyperspectral sensor collects reflectance spectra in the range 350-2500 nm, which allows the identification of not only inorganic but also organic materials. In this paper, it was used for non-invasive and non-destructive characterization of pictorial layers in paintings. The results show that their main spectral differences locate between 1200-2400 nm. It is also indicated that when a binder is mixed with colorants, some modifications occur in respect to its original spectrum.
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Lu, Li-Kuo, and 呂立國. "Isolation and Characterization of Fetal Trophoblasts in Maternal Blood Using a Microfluidic Disk System for Non-invasive Prenatal Diagnosis." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/b2r65y.
Full textAbstract:
碩士國立臺灣大學
應用力學研究所
107
According to the National Health Insurance Administration Ministry of Health and Welfare, the proportion of pregnant women over 35 years old is close to 30%. This phenomenon leads to an increasing proportion of birth defects and stillbirths, so prenatal testing becomes ever more important. Amniocentesis and chorionic villus sampling(CVS) are considered the gold standard for traditional invasive prenatal genetic testing. However, the miscarriage rates were 1.4% after amniocentesis and 1.9% after CVS. Therefore, non-invasive prenatal diagnosis (NIPD) is highly regarded, which can be divided into two categories: obtaining fetal cell-free DNA in maternal blood and separating fetal nucleated cells (cell-based NIPD; cbNIPD) from maternal blood. The cell-free fetal DNA might not receive the complete set of genetic information about fetal. Therefore, the development of isolating fetal nucleated cells approach has the potential to enable comprehensive fetal diagnosis. In 1978, scientists successfully detect and enrich the circulating fetal cells. This study proposes to isolate and characterize fetal extravillous trophoblasts (fetal EVTs) using a microfluidic disk system. The development of microfluidic technology has provided a more effective method for the purify of fetal cells in recent years. We describe a microfluidic disk system that uses density centrifugation to separate fetal EVTs and other nucleated blood cells from a large amount of maternal blood. The blood of 16-20 ml from pregnant women were collected from the Obstetrics and Gynecology Department of National Taiwan University Hospital. The pregnant women were between 31-43 years old and 16-19 weeks pregnant. Fetal cells were identified by immunofluorescence staining (Hoechst, anti-TBA FITC, anti-cytokeratin PE, anti-CD45 APC, anti-CD66b APC). The target cells were recovered by single cell picking technique. The retrieved fetal/maternal cells were confirmed by downstream genomic analysis, including whole genome amplification, polymerase chain reaction, and short tandem repeat. Results show that SRY was successfully demonstrated during the PCR process which enables sex-determining region Y. STR profiling among fetal EVT-derived, maternal cell-derived, and matching amniocentesis STR fingerprints, revealing the feto-maternal relationship between the fetal EVTs and maternal cells. The positive predictive value of the microfluidic disk system for the target fetal EVTs was 53.8%. Future study expects to increase the positive predictive value and provides a solution to researchers and clinicians.
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Bassani, Molinas Maria de los Milagros [Verfasser]. "Transient transfection of HEK293 cells in suspension : process characterization and optimization by applying invasive nucleotide and non-invasive electronic nose technology / von Maria de los Milagros Bassani Molinas." 2005. http://d-nb.info/976524295/34.
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Naïm, Cyrille. "Characterization of Carotid Plaques with Ultrasound Non-Invasive Vascular Elastography (NIVE) : Feasibility and Correlation with High-Resolution Magnetic Resonance Imaging." Thèse, 2013. http://hdl.handle.net/1866/9674.
Full textAbstract:
L’accident vasculaire cérébral (AVC) est une cause principale de décès et de morbidité dans le monde; une bonne partie des AVC est causée par la plaque d’athérosclérose carotidienne. La prévention de l’AVC chez les patients ayant une plaque carotidienne demeure controversée, vu les risques et bénéfices ambigus associés au traitement chirurgical ou médical. Plusieurs méthodes d’imagerie ont été développées afin d’étudier la plaque vulnérable (dont le risque est élevé), mais aucune n’est suffisamment validée ou accessible pour permettre une utilisation comme outil de dépistage. L’élastographie non-invasive vasculaire (NIVE) est une technique nouvelle qui cartographie les déformations (élasticité) de la plaque afin de détecter les plaque vulnérables; cette technique n’est pas encore validée cliniquement. Le but de ce projet est d’évaluer la capacité de NIVE de caractériser la composition de la plaque et sa vulnérabilité in vivo chez des patients ayant des plaques sévères carotidiennes, en utilisant comme étalon de référence, l’imagerie par résonance magnétique (IRM) à haute-résolution. Afin de poursuivre cette étude, une connaissance accrue de l’AVC, l’athérosclérose, la plaque vulnérable, ainsi que des techniques actuelles d’imagerie de la plaque carotidienne, est requise.
Trente-et-un sujets ont été examinés par NIVE par ultrasonographie et IRM à haute-résolution. Sur 31 plaques, 9 étaient symptomatiques, 17 contenaient des lipides, et 7 étaient vulnérables selon l’IRM. Les déformations étaient significativement plus petites chez les plaques contenant des lipides, avec une sensibilité élevée et une spécificité modérée. Une association quadratique entre la déformation et la quantité de lipide a été trouvée. Les déformations ne pouvaient pas distinguer les plaques vulnérables ou symptomatiques.
En conclusion, NIVE par ultrasonographie est faisable chez des patients ayant des sténoses carotidiennes significatives et peut détecter la présence d’un coeur lipidique. Des études supplémentaires de progression de la plaque avec NIVE sont requises afin d’identifier les plaques vulnérables.Stroke is a leading cause of death and morbidity worldwide, and a significant proportion of strokes are caused by carotid atherosclerotic plaque rupture. Prevention of stroke in patients with carotid plaque poses a significant challenge to physicians, as risks and benefits of surgical or medical treatments remain equivocal. Many imaging techniques have been developed to identify and study vulnerable (high-risk) atherosclerotic plaques, but none is sufficiently validated or accessible for population screening. Non-invasive vascular elastography (NIVE) is a novel ultrasonic technique that maps carotid plaque strain (elasticity) characteristics to detect its vulnerability; it has not been clinically validated yet. The goal of this project is to evaluate the ability of ultrasound NIVE strain analysis to characterize carotid plaque composition and vulnerability in vivo in patients with significant plaque burden, as determined by the reference standard, high resolution MRI. To undertake this study, a thorough understanding of stroke, atherosclerosis, vulnerable plaque, and current non-invasive carotid plaque imaging techniques is required. Thirty-one subjects underwent NIVE and high-resolution MRI of internal carotid arteries. Of 31 plaques, 9 were symptomatic, 17 contained lipid and 7 were vulnerable on MRI. Strains were significantly lower in plaques containing a lipid core compared to those without lipid, with high sensitivity and moderate specificity. A quadratic fit was found between strain and lipid content. Strains did not discriminate symptomatic patients or vulnerable plaques. In conclusion, ultrasound NIVE is feasible in patients with significant carotid stenosis and can detect the presence of a lipid core. Further studies of plaque progression with NIVE are required to identify vulnerable plaques.
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Ahmed, Manal Bayomi Mahmoud. "The susceptibility of primordial germ cells to malignant transformation and isolation and characterization of members of a new gene family differentially expressed in invasive and non-invasive immortalized male germ cells." Doctoral thesis, 2002. http://hdl.handle.net/11858/00-1735-0000-0006-ABE4-9.
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Ahmed, Manal Bayomi Mahmoud [Verfasser]. "The susceptibility of primordial germ cells to malignant transformation and isolation and characterization of members of a new gene family differentially expressed in invasive and non-invasive immortalized male germ cells / vorgelegt von Manal Bayomi Mahmoud Ahmed." 2001. http://d-nb.info/96419323X/34.
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Agarwal, Umesh. "Characterization of a non-invasive hyperspectral microscopic imaging system for monitoring the vascular development of diabetic retinopathy in the Double-Knock-Out apoE-/- db/db Mouse Model." 2009. http://hdl.handle.net/10106/2082.
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Riedel, Simone Stefanie. "Characterization of the fluorescence protein FP635 for in vivo imaging and establishment of a murine multiple myeloma model for non-invasive imaging of disease progression and response to therapy." Doctoral thesis, 2013. https://nbn-resolving.org/urn:nbn:de:bvb:20-opus-77894.
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Optical in vivo imaging methods have advanced the fields of stem cell transplantation, graft-versus–host disease and graft-versus-tumor responses. Two well known optical methods, based on the transmission of light through the test animal are bioluminescence imaging (BLI) and fluorescence imaging (FLI). Both methods allow whole body in vivo imaging of the same animal over an extended time span where the cell distribution and proliferation can be visualized. BLI has the advantages of producing almost no unspecific background signals and no necessity for external excitation light. Hence, BLI is a highly sensitive and reliable detection method. Yet, the BLI reporter luciferase is not applicable with common microscopy techniques, therefore abolishing this method for cellular resolution imaging. FLI in turn, presents the appealing possibility to use one fluorescent reporter for whole body imaging as well as cellular resolution applying microscopy techniques. The absorption of light occurs mainly due to melanin and hemoglobin in wavelengths up to 650 nm. Therefore, the wavelength range beyond 650 nm may allow sensitive optical imaging even in deep tissues. For this reason, significant efforts are undertaken to isolate or develop genetically enhanced fluorescent proteins (FP) in this spectral range. “Katushka” also called FP635 has an emission close to this favorable spectrum and is reported as one of the brightest far-red FPs. Our experiments also clearly showed the superiority of BLI for whole body imaging over FLI. Based on these results we applied the superior BLI technique for the establishment of a pre-clinical multiple myeloma (MM) mouse model. MM is a B-cell disease, where malignant plasma cells clonally expand in the bone marrow (BM) of older people, causing significant morbidity and mortality. Chromosomal abnormalities, considered a hallmark of MM, are present in nearly all patients and may accumulate or change during disease progression. The diagnosis of MM is based on clinical symptoms, including the CRAB criteria: increased serum calcium levels, renal insufficiency, anemia, and bone lesions (osteolytic lesions or osteoporosis with compression fractures). Other clinical symptoms include hyperviscosity, amyloidosis, and recurrent bacterial infections. Additionally, patients commonly exhibit more than 30% clonal BM plasma cells and the presence of monoclonal protein is detected in serum and/or urine. With current standard therapies, MM remains incurable and patients diagnosed with MM between 2001 and 2007 had a 5-year relative survival rate of only 41%. Therefore, the development of new drugs or immune cell-based therapies is desirable and necessary. To this end we developed the MOPC-315 cell line based syngeneic MM mouse model. MOPC-315 cells were labeled with luciferase for in vivo detection by BLI. We validated the non-invasively obtained BLI data with histopathology, measurement of idiotype IgA serum levels and flow cytometry. All methods affirmed the reliability of the in vivo BLI data for this model. We found that this orthotopic MM model reflects several key features of the human disease. MOPC-315 cells homed efficiently to the BM compartment including subsequent proliferation. Additionally, cells disseminated to distant skeletal parts, leading to the typical multifocal MM growth. Osteolytic lesions and bone remodeling was also detected. We found evidence that the cell line had retained plasticity seen by dynamic receptor expression regulation in different compartments such as the BM and the spleenOptische in vivo bildgebende Verfahren haben die Felder der Stammzelltransplantation, Graft-versus-Host Krankheit und Graft-versus-Tumor Reaktion vorangebracht. Zwei gut bekannte optische Methoden, die auf der transmission von Licht durch das Versuchtier basieren, sind die Biolumineszenz Bildgebung (BLI) und die Fluoreszenz Bildgebung (FLI). Beide Methoden erlauben die in vivo Ganzkörperbildgebung desselben Tieres über lange Zeit wärenddessen die Zellverteilung und Proliferation sichtbar gemacht werden kann. Vorteil der BLI ist, dass beinahe keine unspezifischen Hintergrundsignale erzeugt werden und keine Notwendigkeit für Anregungslicht besteht. Daher ist BLI eine hochsensitive und verlässliche Detektionsmethode. Jedoch erlaubt der BLI Reporter, die Luziferase, keine Anwendung mit gängigen Mikroskopieanwendungen und verhindert daher, dass diese Methode für die Bildgebung auf zellulärer Ebene genutzt werden kann. FLI wiederum bietet die attraktive Möglichkeit einen fluoreszenten Reporter sowohl für die Bildgebung des gesamten Körpers, als auch auf zellulärer Ebene durch die Anwendung von Mikroskopietechniken zu nutzen. Derzeit bestehen noch größere Einschränkungen bei der Arbeit mit fluoreszent markierten Zellen innerhalb eines Tieres. Die allgemeine Autofluoreszenz des umliegenden Gewebes führt zu hohen Hintergrundsignalen. Zusätzlich werden sowohl das Anregungslicht als auch die emittierte Fluoreszenz durch das umliegende Gewebe abgeschwächt. Die Absorption des Lichtes geschieht hauptsächlich durch Melanin und Hämoglobin in Wellenlängen bis zu 650 nm. Daher könnte der Wellenlängenbereich über 650 nm sensitive optische Bildgebung auch in tief liegendem Gewebe ermöglichen. Aus diesem Grund werden erhebliche Anstrenungen unternommen um Fluoreszenzproteine (FP) in diesem spektralen Bereich zu isolieren oder genetisch verbesserte zu entwickeln. „Katushka“ auch FP635 genannt hat eine Emission, die nahe an diesem günstigen Spektrum liegt und wurde als eines der hellsten dunkelroten FPs beschrieben. Wir untersuchten FP635 für die Anwendung als sensitiver Einzelreporter für die Detektion immunologischer Prozesse von der Ganzkörper- bis zur Einzelzellbildgebung. Unsere Experimente zeigten auch deutlich die Überlegenheit der BLI über die FLI für die Ganzkörperbildgebung. Basierend auf diesen Ergebnissen setzten wir die überlegene BLI für die Etablierung eines präklinischen Mausmodells des Multiplen Myeloms (MM) ein. MM ist eine B-Zell Erkrankung wobei maligne Plasmazellen klonal im Knochenmark (BM) älterer Menschen expandieren und erhebliche Morbidität und Sterblichkeit verursacht. Chromosomale Abnormitäten gelten als Kennzeichen des MM, sind bei beinahe allen Patienten vorhanden und können sich während des Krankheitsverlaufes anhäufen oder verändern. Die Diagnose des MM basiert auf klinischen Syptomen inklusive der folgenden Kriterien: erhöhte Serum Kalzium Konzentration, Niereninsuffizienz, Anämie und Knochenläsionen (osteolytische Läsionen oder Osteoporose mit Kompressionsfrakturen). Weitere klinische Symptome beinhalten Hyperviskosität, Amyloidose und wiederkehrende bakterielle Infektionen. Zusätzlich zeigen Patienten verbreitet mehr als 30% klonale BM Plasmazellen und monoklonales Protein ist in Serum und/oder Urin detektierbar. Mit derzeitigen Standardtherapien bleibt MM unheilbar und Patienten, die zwischen 2001 und 2007 mit MM diagnostiziert wurden hatten eine relative 5-jahres Überlebensrate von nur 41%. Daher ist die Entwicklung neuer Medikamente und immunzellbasierten Therapien wünschenswert und notwendig. Zu diesem Zweck entwickelten wir das auf der Zelllinie MOPC-315 basierende syngene MM Mausmodell. Die MOPC-315 Zellen wurden für die in vivo Detektion mittels BLI mit Luziferase markiert. Wir validierten die nichtinvasiv gewonnenen BLI Daten mit Histopathologie, der Messung des idiotypen IgA Spiegels im Serum und Durchflusszytometrie. Alle Methoden bekräftigten die Zuverlässigkeit in vivo BLI Daten für dieses Modell. Wir stellten fest, dass dieses orthotope MM Modell einige Hauptmerkmale der menschlichen Erkrankung widerspiegelt. Die MOPC-315 Zellen wanderten effizient in das BM Kompartiment inklusive darauffolgender Proliferation. Ausserdem, streuten die Zellen in entfernte Teile des Skeletts aus was zum typischen multifokalen MM Wachstum führte. Wir stellten auch osteolytische Läsionen und Knochenumbau fest. Wir fanden Hinweise darauf, dass sich die Zelllinie Plastizität bewahrte was durch die dynamische Regulation der Rezeptorexpression in verschiedenen Kompartimenten, wie dem BM und der Milz, sichtbar wurde
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Simon, Michael [Verfasser]. "Insulin nanocomplexes formed by self-assembly from amine-modified poly(vinyl alcohol)-graft-poly(L-lactide) for non-invasive mucosal delivery : preparation, characterization and in vivo investigations / vorgelegt von Michael Simon." 2006. http://d-nb.info/979338727/34.
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Risticevic, Sanja. "Solid phase microextraction coupled to comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry for metabolite profiling of apples: Potential of non-invasive in vivo sampling assay in characterization of metabolome." Thesis, 2012. http://hdl.handle.net/10012/7006.
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The objective of the current research project relies on implementation of solvent-free, green and environmentally friendly solid phase microextraction (SPME) sample preparation alternative in the area of complex sample characterization. The advantages that the technique offers in comparison to traditional methods of sample preparation including solvent-free implementation, short sample preparation times, small sample amount requirements, advanced automation capability and minimization of matrix effects are effectively employed during ex vivo and laboratory investigations of complex samples. More important, the underlying features of the technique including miniaturized format, nonexhaustive extraction recoveries and on-site compatibility were fully exploited in order to investigate the metabolome of biological systems directly on the site. Hence, in vivo SPME extraction format was employed in direct immersion SPME sampling of biological systems, hence eliminating the crucial prerequisites associated with multiple preparative steps and incorporation of metabolism quenching that are encountered during implementation of traditional sample preparation methods in global metabolite analysis. Furthermore, in vivo sampling format was hyphenated to comprehensive two-dimensional gas chromatography – time-of-flight mass spectrometry (GCxGC-ToFMS) for high-resolution sampling of volatile and semivolatile metabolites in ‘Honeycrisp’ apples.
The initial stages of the project involved evaluation of performance characteristics of commercial SPME extraction coatings in terms of extraction selectivity, extraction sensitivity and desorption efficiency by employing headspace SPME analysis of both aqueous standards spiked with representative volatile and semivolatile metabolites as well as the apple homogenate. DVB/CAR/PDMS coating was selected on the basis of optimum metabolite coverage and extraction sensitivity and was consequently employed during ex vivo and in vivo sampling assays corresponding to determination of volatile and semivolatile metabolites. The former extraction methodology incorporated appropriate sample preparation steps for quenching metabolic activity so that the relevant metabolome profile is not biased against unstable metabolites and those that are susceptible to inter-metabolite conversions which adversely impact preservation of metabolite identity. The two sample preparation assays were compared in terms of metabolite coverage and analytical precision in order to identify SPME route toward characterization of more representative metabolome and determination of instantaneous and more ‘true’ metabolism snapshoot. This is the first report illustrating the implementation of in vivo direct immersion SPME assay for non invasive determination of endogenous fruit metabolites whose profiles and contents are highly correlated to a multitude of influential fruit quality traits.
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Seabra, Ana Carolina Gonçalves. "Development and characterization of a miniaturized ultrasound transceiver to measure blood pressure." Master's thesis, 2021. http://hdl.handle.net/1822/76440.
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Dissertação de mestrado integrado em Engenharia Biomédica (área de especialização em Electrónica Médica)As cardiovascular diseases are one of the most prominent illnesses, a continuous, non-invasive, and comfortable monitoring of blood pressure becomes indispensable. A highly accurate wrist-worn device that derives the blood pressure curve from hemodynamic pulse waves could be the key for telemonitoring anatomical and functional information about arterial health. The use of ultrasound technology holds great promise as a method of measuring critical arterial parameters. The changes in the pressure waveform through the arterial tree enforce a site-specific blood pressure model and calibration. This work investigates the best method for obtaining highly accurate blood pressure values in non-invasive measurements when using an ultrasound sensor designed for use via a wrist-worn device. State-of-the-art blood pressure models were analysed and qualitatively compared. Relevant arterial parameters such as luminal area, flow velocity and pulse wave velocity, of 729 subjects were extracted from a computer-simulated database and served as input parameters for the proposed wearable ultrasound device. In the novel in-silico study, the linear model was the most accurate at the radial artery. An electronic system was designed to acquire the distending diameter of a vessel through echo tracking of the inner walls. The ultrasound echo signal was amplified and filtered, simplifying the post-processing procedure. A specific algorithm was developed to extract the diameter waveform from the ultrasound echo signal and consequent conversion to a pressure waveform. The best model for the radial artery was validated in an ex-vivo experiment, where a porcine artery, combined with a heart-like pump, and the developed electronic system (temporal sampling of 0.5 ms) were used. The ex-vivo experimental pressure measurements demonstrated the high accuracy of the linear model based on the mean arterial pressure calibration with extremely low mean error values of (0.544±2.315) mmHg. This study emphasizes the need to consider site-specific blood pressure models and calibration procedures for high accuracy measurements, while also introducing proof-of-concept of an ultrasound-based device for continuous and non-invasive measurement of blood pressure.
Actualmente, as doenças cardiovasculares são das mais proeminentes, sendo vital uma monitorização contínua da pressão arterial, acessível a todos, não invasiva e confortável. Um dispositivo de alta precisão, usado à volta do pulso, capaz de derivar a pressão arterial a partir de curvas de parâmetros arteriais hemodinâmicos, pode ser a chave para a telemonitorização de informação anatómica e funcional da saúde arterial. A utilização da tecnologia de ultrassons é muito promissora como método de medição de tais parâmetros arteriais críticos. As alterações na forma da onda de pressão ao longo da árvore arterial requerem um modelo de pressão arterial específico para cada local de medição. Este trabalho investiga o melhor método para obter valores de pressão precisos em medições não invasivas, utilizando um sensor de ultrassons incorporado num dispositivo desenhado para uso no pulso. Os modelos de pressão existentes foram analisados e comparados qualitativamente; foram extraídos parâmetros arteriais relevantes (tais como a área luminal e as velocidades do fluxo e da onda de pulso) de 729 indivíduos de uma base de dados simulada que serviram de entrada para os modelos. Neste estudo inovador in-silico, o modelo linear foi o mais preciso para a artéria radial. Foi projectado um sistema electrónico para a aquisição do diâmetro em distensão de um vaso, que toma como princípio de funcionamento o rastreio de eco das paredes internas do vaso. O sinal de eco dos ultrassons é amplificado e filtrado, simplificando o procedimento de pós-processamento; foi, igualmente, desenvolvido um algoritmo específico para extrair a forma da onda do diâmetro do vaso, a partir do sinal de eco de ultrassons, e aplicar a consequente conversão para uma curva de pressão. O melhor modelo para a artéria radial foi validado ex-vivo, na qual foi utilizada uma artéria de porco conjuntamente com o sistema electrónico desenvolvido (amostragem temporal de 0,5 ms). As medições experimentais da pressão ex-vivo comprovaram a alta precisão do modelo linear, calibrado com base na pressão arterial média, com valores de erro médio muito baixos de (0,544±2,315) mmHg. Este estudo realça a necessidade de considerar, para medições de alta precisão, modelos de pressão arterial específicos e adaptados ao local, e introduz a prova de conceito de um dispositivo baseado em ultrassons para medição contínua e não invasiva da pressão arterial.
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Lenz, Michael. "Neuartige Ultraschallmeßverfahren unter Nutzung von Schallfeldinformationen." Doctoral thesis, 2013. https://tud.qucosa.de/id/qucosa%3A27667.
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Die vorliegende Arbeit untersucht, wie die genaue Kenntnis der Sende- und Empfangsschallfelder eines Ultraschallwandlers zur Entwicklung neuer Meßverfahren genutzt werden kann. Insbesondere werden dargestellt:
- ein neuartiges, nichtscannendes Verfahren zur Bestimmung der Krümmung eines Reflektors, basierend auf der Analyse der Wellenfrontkrümmung reflektierter Schallfelder
- ein neuartiges, nichtinvasives Verfahren zur Bestimmung der Schallgeschwindigkeit in einer Flüssigkeit durch Auswertung der Echosignale von im Ausbreitungsmedium vorhandenen Streupartikeln und
- ein Verfahren zur Wandlercharakterisierung durch Messungen in Fluiden mit Streupartikeln, sowie verschiedene Zuordnungen von Schallfeldmerkmalen zu spezifischen Eigenschaften eines Ultraschallwandlers.
Im Zusammenspiel von Simulation und Experiment konnten die Funktionstüchtigkeit aller Meßverfahren nachgewiesen und vielversprechende innovative Ansätze für zukünftige Entwicklungen angeregt werden:
1. Das nichtscannende Verfahren zur Krümmungsmessung erlaubt bei guter Justage eine Krümmungsbestimmung von Reflektoren mit Radien zwischen 6 und 11 mm mit einer Unsicherheit von ungefähr 0,5 mm. In Kombination mit herkömmlichen scannenden Verfahren bietet es Ansätze zur präzisen Größenbestimmung von Fehlern in der zerstörungsfreien Prüfung.
2. Das Verfahren zur nichtinvasiven Schallgeschwindigkeitsmessung erlaubt eine Bestimmung von Schallgeschwindigkeiten mit einer statistischen Meßunsicherheit von 0,1 %. Mögliche Weiterentwicklungen zur Messung der Schallgeschwindigkeit mit örtlicher Auflösung und zur Gewinnung neuer Diagnosemöglichkeiten in Metallurgie (nichtinvasive Charakterisierung von Mischungsvorgängen) und Biomedizintechnik (nichtinvasive Temperaturmessung in Körpergewebe zur Überwachung der Hyperthermiebehandlung, Gewebecharakterisierung) werden erläutert.
Aus verschiedenen bekannten sowie einem neuartigen, leicht anwendbaren Meßverfahren werden neue Schlüsse gezogen a) zur Bestimmung der akustisch effektiven Elementgröße von Wandlerelementen mittels Schallfeldmessungen, b) zur Qualitätssicherung im Hinblick auf Schallkopfasymmetrien und c) zur Verbesserung von Schallfeldsimulationen.The current thesis explores how the precise knowledge of the sending and receiving sound fields of an ultrasonic transducer can contribute to the development of novel measuring techniques. Emphasis is placed on: - a novel, non-scanning method for the determination of the curvature radius of a spherical reflector, based on the analysis of the wave front curvature of the reflected sound field, - a novel non-invasive method for sound velocity measurements in fluids using the echo signals from scattering particles, and - novel conclusions on how to use well-known sound field measurement methods for transducer characterisation, as well as an introduction to a novel easy-to-use method for transducer characterisation exploiting the echo signals from scattering particles. Proof of concept is shown for all methods by simulation and measurement, and different promising improvements for further techniques are suggested: - The non-scanning method for curvature measurements makes it possible to determine reflector radii between 6 and 11 mm with an uncertainty of about 0.5 mm, provided that there is a good reflector alignment. In combination with conventional methods, a novel approach for the determination of the size of discontinuities in non-destructive testing is outlined. - The method for non-invasive sound velocity measurements allows the determination of sound velocity in homogeneous fluids with a statistical uncertainty of 0.1 %. Future improvements are suggested to allow sound velocity measurements with local resolution, which enables novel approaches for metallurgy (non-invasive characterisation of mixing processes) and biomedical engineering (non-invasive temperature control for hyperthermia treatment, tissue characterisation). - New conclusions are drawn based on well-established and a novel easy-to-implement measurement method regarding a) the determination of the acoustically effective element size of transducer elements, b) transducer asymmetries, thereby improving quality control, and c) the improvement of sound field simulations.
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Póvoa, Joana Andreia Simões. "Genetic characterization of weakfish Cynoscion Regalis (Bloch & Schneider, 1801) in its non-native distribution : the case of portuguese coastal waters." Master's thesis, 2021. http://hdl.handle.net/10400.12/8604.
Full textAbstract:
Dissertação de Mestrado apresentada no ISPA – Instituto Universitário para obtenção de grau de Mestre na especialidade de Biologia Marinha e Conservação.A corvinata Cynoscion regalis é um cianídeo com distribuição nativa na costa leste norte-americana e Canadá. No entanto, foram registados alguns avistamentos na Europa desde 2009, nomeadamente em águas portuguesas. Devido ao potencial invasivo desta espécie, este estudo visa a primeira caracterização genética da corvinata em Portugal. A análise do fragmento D-loop de C. regalis revelou que as localizações portuguesas têm valores mais baixos de diversidade genética comparativamente à Flórida. A rede de haplótipos construída revelou o baixo polimorfismo desta espécie, não havendo partilha de haplótipos entre os dois lados do Atlântico. A AMOVA realizada mostrou estrutura populacional para a espécie, enquanto a análise hierárquica revelou ausência de estrutura genética entre populações em águas portuguesas. A análise de conteúdos estomacais revelou que a maioria dos indivíduos ingeridos eram coespecíficos. A ingestão de espécies como Atherina presbyter, Spondyliosoma cantharus e Engraulis encrasicolus confirma a ocupação do estuário por parte da corvinata, podendo potenciar os efeitos negativos na sua distribuição não nativa.
Weakfish Cynoscion regalis is a native sciaenid from the east coast of north-America and Canada. However, this species has been recorded in Europe since 2009, namely in Portuguese waters. Due to its invasive potential, this study aims to be the first genetic characterization of weakfish in Portugal. The analysis of the D-loop fragment of C. regalis revealed that Portuguese populations present lower values of genetic diversity compared to Florida. The haplotype network revealed the low polymorphic nature of this species, with no haplotypes being shared between Atlantic coasts. The AMOVA analysis revealed population structure for the species, while the hierarchical analysis yielded no genetic structure among populations within Portuguese waters. Stomach content analysis showed that the majority of the ingested prey were conspecifics. The ingestion of species such as Atherina presbyter, Spondyliosoma cantharus and Engraulis encrasicolus confirms the weakfish occupation of the estuary, potentially enhancing the negative effects at its non-native range.