Thèses : « Diagnostic proce »

1

MASSETTI, GEMMA. "A DIGITAL BATTERY FOR UNILATERAL SPATIAL NEGLECT: HOW NEW TECHNOLOGIES CAN MAKE THE NEUROPSYCHOLOGICAL EVALUATION MORE ACCURATE AND SENSITIVE." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2022. http://hdl.handle.net/10281/374741.

Texte intégral

Résumé :

La negligenza spaziale unilaterale (NSU) è un disturbo neuropsicologico dovuto a eventi cerebrovascolari (CVA), tumori cerebrali e lesioni cerebrali acquisite. I pazienti con NSU falliscono nell’orientarsi verso, rispondere e riportare eventi sensoriali che si verificano nel lato dello spazio e del corpo controlaterale al lato della lesione (tipicamente, il lato sinistro in pazienti con danno cerebrale destro), e nell’esplorare queste porzioni di spazio. La valutazione della NSU si basa soprattutto sulla valutazione delle prestazioni dei pazienti a test carta-e-matita. Tuttavia, sono ora disponibili evidenze emergenti che le tecnologie che si basano sui computer possano migliorare le procedure diagnostiche. I test computerizzati possono offrire più sensibilità e flessibilità, registrando molte più informazioni (ad es., l’accuratezza e i tempi di reazione simultaneamente). Queste caratteristiche riducono le possibilità di errore umano e permettono misurazioni quantitative e continue nei singoli pazienti, includendo un monitoraggio individuale e sensibile dei cambiamenti prestazionali lungo il corso di ripetute valutazioni. L’obiettivo principale della presente tesi di dottorato era quello di validare preliminarmente dei test digitali appositamente creati, comparandoli a test carta-e-matita tradizionalmente usati nella pratica clinica per la diagnosi di NSU. Tutti questi test sono stati creati in un ambiente digitale facile da usare e basato sull’utilizzo di uno schermo touch e di una penna digitale, così da simulare il tradizionale atto di scrittura. All’interno di tre studi, i partecipanti sani e i pazienti con danno cerebrale destro, con e senza NSU, sono stati sottoposti sia ai testi digitali che ai test carta-e-matita. Le analisi dei dati hanno mostrato risultati promettenti, suggerendo che i test digitali potrebbero condurre a una valutazione neuropsicologica più sensibile e precisa, smascherando inoltre casi di neglect residuale. Infine, i risultati presenti incoraggiano la raccolta di dati normativi per poter adottare i test digitali nella pratica clinica. Unilateral Spatial Neglect (USN) is a neuropsychological disorder due to cerebrovascular accidents (CVA), cerebral tumours and brain injuries. USN patients fail to orient towards, respond to and report sensory events occurring in the side of space and the body contralateral to the side of the lesion (typically the left side in the right-brain-damaged patients), and to explore these portions of space. The assessment of USN has relied mainly on evaluating patients’ performances at paper-and-pencil tests. Nevertheless, emerging evidence that computer-based technologies may improve the assessment procedure is now available. More sensitivity and flexibility may indeed be offered by computerised tests, which typically record much more information (i.e., accuracy and reaction time measures simultaneously). These features reduce the chances of human error and allow for quantitative, continuous measures and even significance levels in single patients, including sensitive individual monitoring of performance changes through repeated assessments. The main aim of the present PhD thesis was to preliminarily validate purposely created digital tests, compared to similar classic paper-and-pencil tests traditionally used in the clinical setting for USN assessment. All these tasks were built up in a user-friendly digital environment based on touch screens and digital pens, simulating the act of filling in a paper-and-pencil set-up with the advantages of the touch system. Within three studies, healthy participants and right-brain-damaged patients with and without USN performed both the digital and the paper-and-pencil versions of tests. Data analyses showed promising results, suggesting that digital tests could lead to a more sensitive and precise neuropsychological evaluation, also unmasking cases of covert USN. Lastly, the present findings encourage the collection of normative data in order to adopt digital tests in clinical practice.

Styles APA, Harvard, Vancouver, ISO, etc.

2

Bopp, Cécile. "The proton as a dosimetric and diagnostic probe." Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAE023/document.

Texte intégral

Résumé :

L’imagerie proton est étudiée comme alternative à la tomodensitométrie X pour la planification de traitement en hadronthérapie. En obtenant directement les pouvoirs d’arrêt relatifs des tissus, l’incertitude sur le parcours des particules pourrait être réduite. Un scanner à protons est constitué d’un calorimètre ou d’un détecteur de parcours afin d’obtenir l’information sur l’énergie déposée par chaque proton dans l’objet imagé et de deux ensembles de trajectographes enregistrant la position et direction de chaque particule en amont et en aval de l’objet. Ce travail concerne l’étude des données d’un scanner à protons et l’utilisation possible de toutes les informations enregistrées. Une étude de reconstruction d’image a permis de montrer que les informations sur le taux de transmission et sur la déviation de chaque particule peuvent être utilisées pour produire des images aux propriétés visuelles intéressantes pour le diagnostic. La preuve de concept de la possibilité d’une imagerie quantitative utilisant ces informations est présentée. Ces résultats sont une première étape vers l’imagerie proton utilisant toutes les données enregistrées Proton computed tomography is being studied as an alternative to X-ray CT imaging for charged particle therapy treatment planning. By directly mapping the relative stopping power of the tissues, the uncertainty on the range of the particles could be reduced. A proton scanner consists in a calorimeter or range-meter to obtain the information on the energy lost by each proton in the object, as well as two sets of tracking planes to record the position and direction of each particle upstream and downstream from the object. This work concerns the study of the outputs of a proton scanner and the possible use of all the recorded information. A reconstruction study made it possible to show that the information on the transmission rate and on the scattering of each particle can be used to produce images with visual properties that could be of interest for diagnostics. The proof of concept of the possibility of quantitative imaging using this information is also put forward. These results are the first step towards a clinical use of proton imaging with all the recorded data

Styles APA, Harvard, Vancouver, ISO, etc.

3

Sinclair, Brian Collins. "Langmuir probe diagnostics of the VASIMR engine /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Dec%5FSinclair.pdf.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

4

Mezger, Anja. "Padlock Probe-Based Assays for Molecular Diagnostics." Doctoral thesis, Stockholms universitet, Institutionen för biokemi och biofysik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-116214.

Texte intégral

Résumé :

Treatment success often depends on the availability of accurate and reliable diagnostic assays to guide clinical practitioners in their treatment choices. An optimal test must excel in specificity and sensitivity, and depending on the application area time, low-cost and simplicity are equally important. For instance, time is essential in infectious diagnostics but this is less important in non-invasive prenatal testing (NIPT). In NIPT, specificity and sensitivity are the most important parameters. In this thesis I describe the development of four different methods, all based on padlock probes and rolling circle amplification, intended for molecular diagnostics. Application areas range from infectious disease diagnostics to NIPT and oncology. The methods described have in common that they overcome certain limitations of currently available assays. This thesis includes two new assays targeting infectious agents: one assay specifically detecting a highly variable double stranded RNA virus and the second assay demonstrating a new format of antibiotic susceptibility testing, which is rapid and generally applicable to different pathogens. Furthermore, I describe the development of a method that uses methylation markers to enrich fetal DNA, accurately quantify chromosome ratios and thus, detecting trisomy 21 and 18. The fourth method described in this thesis uses gap-fill ligation of padlock probes to detect diagnostic relevant point mutations with high specificity in situ. The assays presented have the potential, after automation and successful validation and verification studies, to be implemented into clinical practice. Furthermore, these assays demonstrate the wide applicability of padlock probes which, due to their properties in regard to specificity and multiplexity, are useful tools for nucleic acid detection in vitro as well as in situ. At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.

Styles APA, Harvard, Vancouver, ISO, etc.

5

Sinclair, Brian C. "Langmuir probe diagnostics of the VASIMR engine." Thesis, Monterey, California. Naval Postgraduate School, 2005. http://hdl.handle.net/10945/1821.

Texte intégral

Résumé :

NASAâ s VAriable Specific Impulse Magnetoplasma Rocket Engine (VASIMR) will provide a highly efficient propulsion source that can dramatically reduce Martian transit times, provide for more abort contingencies, and protect astronauts from space radiation with its highly radiation-absorbent hydrogen fuel. The VASIMR is still in its developmental infancy and requires many years of research before its initial operational capability. Much is still unknown about the complex plasma interactions in the exhaust. A Langmuir probe was designed, constructed, and operated to determine current density radial profiles and total particle flux at various stages in the exhaust of VASIMR. The Langmuir probe results proved that the exhaustâ s radial profile is Gaussian, experimentally validated predictions of magnetic field line dragging, and verified the ionization efficiency of VASIMR.

Styles APA, Harvard, Vancouver, ISO, etc.

6

Martin-Hidalgo, Julio. "Sequential Quadrature Measurements for Plasma Diagnostics." DigitalCommons@USU, 2014. https://digitalcommons.usu.edu/etd/2297.

Texte intégral

Résumé :

The ionosphere is the atmosphere layer characterized by its high concentration of ionized plasma. It has a great impact on radio communications with satellites, causing disturbances and disruptions. Therefore, it is important to understand and predict the ionosphere characteristics. The Sweeping Impedance Probe (SIP) is an instrument for characterizing the ionosphere used for many decades with great success. In this thesis, a new SIP architecture design is presented using the latest techniques and components available. The design is detailed and analyses have been performed to ensure the required performances. The new SIP will be flown in the Auroral Spatial Structures Probe (ASSP) sounding rocket mission in early 2015, and it is expected it will make the most accurate measurements to date. Lastly, the conclusions of this project are presented and future work is outlined for what will become the next generation of SIP instruments.

Styles APA, Harvard, Vancouver, ISO, etc.

7

Therond, Frédéric. "Diagnostic electromagnetique d'objets rayonnants complexes par une technique de champ proche." Paris 11, 1995. http://www.theses.fr/1995PA112545.

Texte intégral

Résumé :

L'objectif de cette these est la detection de points de fuite electromagnetiques sur des structures metalliques. L'approche consiste en une transformation champ proche / champ tres proche, en utilisant les courants induits sur l'objet comme donnee intermediaire. La structure testee est consideree comme une antenne a l'emission dont on mesure le champ en zone proche en coordonnees spheriques. Ce champ proche sert de base a l'inversion pour reconstruire les courants induits sur l'objet rayonnant. On suppose connues la forme de l'objet et sa position dans l'espace. Une fois le courant sur l'objet rayonnant connu, le champ peut etre calcule en n'importe quel point de l'espace et, en particulier, en zone tres proche. Il s'agit d'un probleme de diffraction inverse de type source, tridimensionnel, vectoriel, lineaire, mais mal pose. L'equation de base est l'efie (electric field integral equation), la methode de regularisation est de type tikhonov associee a la methode de validation croisee generalisee pour choisir le parametre de regularisation. Une premiere phase de validation est realisee sur des structures filaires. Le code de calcul nec est utilise pour obtenir des resultats de reference. Cette etape demontre la viabilite de l'algorithme et permet son evaluation vis-a-vis d'erreurs aleatoires et systematiques. La methode est ensuite appliquee a des objets complexes a partir de mesures reelles de champ proche. Les tests sont conduits sur des objets de 50 cm, entre 600 mhz et 3700 mhz. Les resultats attestent des capacites de la procedure de diagnostic a localiser les points de fuite et/ou a discriminer parmi plusieurs zones potentielles de rayonnement

Styles APA, Harvard, Vancouver, ISO, etc.

8

Hendron, Jacqueline Mary. "Ion probe and optical spectroscopy studies of low temperature laser produced-plasmas." Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337038.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

9

Le, Ny Mathieu. "Diagnostic non invasif de piles à combustible par mesure du champ magnétique proche." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00844407.

Texte intégral

Résumé :

Cette thèse propose une technique innovante de diagnostic non invasive pour les systèmes piles à combustible. Cette technique s'appuie sur la mesure de la signature magnétique générée par ces systèmes. A l'aide de ces champs magnétiques externes, il est possible d'obtenir une cartographie de la densité de courant interne par résolution d'un problème inverse. Ce problème est néanmoins mal posé : la solution est non unique et est extrêmement sensible au bruit. Des techniques de régularisation ont ainsi été mises en place pour filtrer les erreurs de mesures et obtenir une solution physiquement acceptable. Afin d'augmenter la qualité de reconstruction des courants, nous avons conçu notre outil de diagnostic de manière à ce qu'il soit uniquement sensible aux défaillances de la pile (capteur de défauts). De plus, cette reconstruction se base sur un nombre extrêmement faible de mesures. Une telle approche facilite l'instrumentation du système et augmente la précision et la rapidité de celui-ci. La sensibilité de notre outil à certaines défaillances (assèchements, appauvrissement en réactifs, dégradations) est démontrée.

Styles APA, Harvard, Vancouver, ISO, etc.

10

Cheng, Adelbert S. (Adelbert Su-Tseh). "The head gasket ionization probe as a combustion diagnostic for spark ignition engines." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/12283.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

11

Macquisten, M. A. "The pulsed electric discharge as an acoustic probe for combustion chamber diagnostics." Thesis, London South Bank University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373899.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

12

Partridge, James Michael. "Development and Implementation of diagnostics for unsteady small-scale plasma plumes." Worcester, Mass. : Worcester Polytechnic Institute, 2009. http://www.wpi.edu/Pubs/ETD/Available/etd-011409-150444/.

Texte intégral

Résumé :

Dissertation (Ph.D.)--Worcester Polytechnic Institute. Keywords: TLP; RPA; retarding potential analyzer; triple Langmuir Probe; plume; probe; diagnostic; thruster; Plasma. Includes bibliographical references (leaves 183-190).

Styles APA, Harvard, Vancouver, ISO, etc.

13

Larici, Fabrizio. "Prove non distruttive e meccaniche ai fini della diagnostica energetica e strutturale di edifici storici." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2446/.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

14

Fourel, Valérie. "Auto-anticorps associés à la cirrhose biliaire primitive : étude d'un aspect de fluorescence atypique proche de l'anti-mitochondrie de type 2." Paris 5, 1991. http://www.theses.fr/1991PA05P174.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

15

Abbaszadegan, Morteza 1955. "Detection of Giardia cysts by cDNA probe and application to water samples." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/191163.

Texte intégral

Résumé :

Giardia is the most common human parasite infection in the United States causing a lengthy diarrhea. Transmission of Giardia is by the fecal-oral route and numerous waterborne outbreaks have been documented. The Environmental Protection Agency has regulated Giardia in drinking water through the "Surface Water Treatment Rule." Current methods for detection of Giardia in water rely primarily on microscopic observation of water concentrates by immunofluorescent techniques. We evaluated the efficacy of using a gene-specific probe for the detection of Giardia species in water. A cDNA probe, 265 base pairs long, from the small subunit of rRNA of Giardia lamblia was used for detection of cysts. The replicative form of M13 vector with insert was isolated from lysed host E. coli XL1- Blue and used for production of the cDNA probe by nick translation with ³²P-labeled nucleotides. Seven different protocols were tested for extracting nucleic acids from the cysts. Using the most efficient procedure, disrupting Giardia cysts with glass beads in the presence of proteinase K, as few as 1 to 5 cysts per ml can be detected in water sample concentrates by dot-blot hybridization assays. Environmental concentrates from secondary and tertiary treated sewage or surface waters were screened for Giardia cysts by immunofluorescent and the genespecific probe. Positive signals were observed in sewage and surface water samples without floatation at ten fold greater dilutions than after floatation. It appeared that gene probe detection was slightly more sensitive than microscopic detection of Giardia cysts for wastewater samples. In six surface water samples and two sewage sample no positive results were found either by the cDNA probe or immunofluorescent. Usually, DNA probes are radiolabeled and the most commonly used is ³²P. ³²P is expensive, hazardous and has an extremely short half-life of 14.3 days, necessitating frequent preparation of the nucleic acid probes. Three non-radioactive labeling methods, chemiluminescence, enzyme-linked immunoassay and enhanced chemiluminescence were evaluated. The cDNA probe was labeled by nick translation for chemiluminescence method. Biotinylated deoxyuridine triphosphate was used in place of deoxythymidine triphosphate to produce biotinylated DNA strands. The result of hybridization was visualized by chemiluminescenct detection of DNA. The sensitivity of the chemiluminescent method and the 32P labeled probe was 0.1 pg of DNA in a slot-blot hybridization assay.

Styles APA, Harvard, Vancouver, ISO, etc.

16

Lyons, Laurence Anthony. "Construction and operation of a Mirror Langmuir Probe diagnostic for the Alcator C-Mod tokamak." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40321.

Texte intégral

Résumé :

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007. This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. Includes bibliographical references (p. 119-120). Langmuir probe diagnostic systems presently employed on Alcator C-Mod and elsewhere generally suffer from a severe limitation: unless multiple electrode or high-frequency bias techniques are employed, these systems can not resolve the rapid changes in plasma electron temperature, floating potential and ion saturation current that are associated with plasma turbulence. Moreover, no existing system can provide real-time output of these three parameters using a single electrode. To remedy this limitation, an advanced, high-bandwidth Langmuir probe system has been constructed for Alcator C-Mod using state-of-the-art design tools and components. The system produces a fast-switched, three-state probe bias waveform and employs a new method for outputting plasma conditions in real-time, a 'Mirror Langmuir Probe' (MLP), which utilizes high-bandwidth bipolar transistors to electrically simulate a Langmuir probe's response. Detailed information on the design, construction and performance of this new diagnostic is described in this thesis, representing the first proof-of-principle demonstration of the MLP technique. The MLP system was found to meet all the performance goals set forth at the beginning of the project: real-time output of electron temperature, floating potential and ion saturation current, ability to track changes in plasma parameters within a ~1 [mu]s timescale, while utilizing only a single Langmuir electrode. The system was tested using an 'electronic Langmuir probe' and also using an actual Langmuir probe in Alcator C-Mod. In both cases, the system accurately locked onto changing plasma conditions (< ~5% error in outputted parameters), with the exception of some severe transient events found in C-Mod plasmas (ELMs), which challenged the system's accuracy. (cont.) Further refinements to the system have been identified to handle such cases. The MLP clearly demonstrated superior performance to existing Langmuir probe systems on Alcator C-Mod and should enable researchers to study edge plasma turbulence in much greater detail in the future. by Laurence Anthony Lyons. S.M.

Styles APA, Harvard, Vancouver, ISO, etc.

17

Gajdoš, Petr. "Akustická diagnostika strojů." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230417.

Texte intégral

Résumé :

The aim of this master´s thesis is to work out a comparison and evaluation of selected methods used for sound field mapping. Thesis will include software tools and results of sample measurement on test object for each mapping method.

Styles APA, Harvard, Vancouver, ISO, etc.

18

Akhras, Michael S. "Nucleic Acid Based Pathogen Diagnostics." Doctoral thesis, KTH, Skolan för bioteknologi (BIO), 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4684.

Texte intégral

Résumé :

Pathogenic organisms are transmitted to the host organism through all possible connected pathways, and cause a myriad of diseases states. Commonly occurring curable infectious diseases still impose the greatest health impacts on a worldwide perspective. The Bill & Melinda Gates Foundation partnered with RAND Corporation to form the Global Health Diagnostics Forum, with the goal of establishing and interpreting mathematical models for what effects a newly introduced point-of-care pathogen diagnostic would have in developing countries. The results were astonishing, with potentially millions of lives to be saved on an annual basis. Golden standard for diagnostics of pathogenic bacteria has long been cultureable medias. Environmental biologists have estimated that less than 1% of all bacteria are cultureable. Genomic-based approaches offer the potential to identify all microbes from all the biological kingdoms. Nucleic acid based pathogen diagnostics has evolved significantly over the past decades. Novel technologies offer increased potential in sensitivity, specificity, decreased costs and parallel sample management. However, most methods are confined to core laboratory facilities. To construct an ultimate nucleic acid based diagnostic for use in areas of need, potential frontline techniques need to be identified and combined. The research focus of this doctoral thesis work has been to develop and apply nucleic acid based methods for pathogen diagnostics. Methods and assays were applied to the two distinct systems i) screening for antibiotic resistance mutations in the bacterial pathogen Neisseria gonorrhoeae, and ii) genotype determination of the cancer causative Human Papillomavirus (HPV). The first part of the study included development of rapid, direct and multiplex Pyrosequencing nucleic acid screenings. With improved methodology in the sample preparation process, we could detect an existence of multiple co-infecting HPV genotypes at greater sensitivities than previously described, when using the same type of methodology. The second part of the study focused on multiplex nucleic acid amplification strategies using Molecular Inversion Probes with end-step Pyrosequencing screening. The PathogenMip assay presents a complete detection schematic for virtually any known pathogenic organism. We also introduce the novel Connector Inversion Probe, a padlock probe capable of complete gap-fill reactions for multiplex nucleic acid amplifications. Patogena organismer smittas till värd organismen genom alla möjliga kontaktnätverk och skapar en mångfald olika sjukdomstillstånd. Dock är det fortfarande vanligt förekommande behandlingsbara infektiösa sjukdomar som orsakar den största hälsoförlusten, sett från ett globalt perspektiv. Bill och Melinda Gates Stiftelsen samarbetade med RAND kooperation för att forma “The Global Health Diagnostics Forum”. Deras mål var att etablera och analysera matematiska modeller för vilka effekter en ny diagnostisk metod utrustat för fältarbete skulle ha i utvecklingsländer. Resultaten var häpnadsveckande, med potentiellt miljoner av liv som skulle kunna räddas på en årlig basis. Den etablerade standarden för diagnostik av patogena bakterier har länge varit kultiveringsmedia baserad. Miljö specialiserade biologer har estimerat att mindre än 1 % av alla bakterie arter går att kultivera. Dock erbjuder genetiska analyser potentialen att kunna identifiera alla mikrober från alla de biologiska rikena. Nukleinsyrebaserade diagnostiska metoder har märkbart förbättrats över de senaste årtionden. Nya tekniker erbjuder utökad sensitivitet, selektivitet, sänkta kostnader och parallella analyser av patient prover. Dock är de flesta metoderna begränsade till standardiserade laboratoriemiljöer. För att konstruera en väl fungerande diagnostisk fältutrustning för användning i problem områden, behöver världsledande tekniker identifieras och kombineras. Fokuseringsområdet för denna doktorsavhandling har varit att utveckla och utföra nukleinsyrebaserade metoder för patogen diagnostik. Metoder och experimentella utförande applicerades på två distinkta system i) sökning av antibiotika resistens relaterade mutationer i den patogena bakterien Neisseria gonorrhoeae och ii) genotypning av det cancer orsakande Humana Papillomaviruset (HPV). Den första delen av studien inriktade sig mot utveckling av snabba, direkta och multiplexa Pyrosekvenserings baserade nukleinsyreanalyser. Med förbättrad provprepareringsmetodologi kunde vi detektera multipla HPV infektioner med högre sensitivitet än vad tidigare beskrivits med liknande metodologi. Den andra delen av studien fokuserades på multiplexa nukleinsyre amplifikationer med “Molecular Inversion Probe” tekniken med sista steg Pyrosekvenserings analys. “PathogenMip assay” erbjuder ett komplett detektionsprotokoll för alla kända patogena organismer. Vi introducerar även den nya “Connector Inversion Probe”, en “Padlock Probe” kapabel att genomföra kompletta gap fyllningar för multiplex nukleinsyre amplifiering. QC 20100624

Styles APA, Harvard, Vancouver, ISO, etc.

19

Wolber, Jan. "Hyperpolarized 129Xe as an NMR probe for functional studies." Thesis, Institute of Cancer Research (University Of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341895.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

20

Teliban, Iulian [Verfasser]. "Spatio-temporal diagnostics of plasma fluctuations with probe arrays and statistical techniques / Iulian Teliban." Kiel : Universitätsbibliothek Kiel, 2008. http://d-nb.info/1019553065/34.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

21

Wantock, Thomas. "Thrust balance performance characterisation and internal Langmuir probe plasma diagnostics for a Halo thruster." Thesis, University of Surrey, 2018. http://epubs.surrey.ac.uk/845862/.

Texte intégral

Résumé :

Electric Propulsion (EP) systems can enable novel spacecraft missions requiring high total change in velocity, owing to their high specific impulse compared to chemical propulsion systems. Mature devices, such as Hall Effect Thrusters (HETs), have accumulated significant flight heritage. How- ever, established technologies do not satisfy the requirements of the rapidly growing small satellite sector, because of adverse scaling to low powers. The Halo thruster concept falls within the cat- egory of Cusped Field Thrusters (CFTs), aimed at addressing this issue. The concept concerns the use of ‘magnetic null regions’, formed through the deliberate cancellation of magnetic fields. Two such regions are produced in the thruster, a ‘null point’ at the thruster exit and an annular ‘halo’ near the anode. The work presented in this thesis has provided foundational knowledge of the performance and internal physics of the Halo thruster, using a 5 cm channel diameter, electromagnet laboratory model. Measurements of thrust, specific impulse and thrust efficiency were obtained over a wide range of operating conditions using a pendulum thrust balance in representative high vacuum, and the sensitivity of the measured performance to facility effects was assessed. Trends in plasma potential, electron temperature and plasma density internal to the discharge channel were obtained using a translating Langmuir probe, allowing the basic physics of operation of the device to be inferred. The thruster was found to exhibit comparable performance to other CFTs, with measurements shown to be robust to facility effects. Internal plasma measurements revealed behaviour similar to that of the Cylindrical Hall Thruster, with some differences due to the presence of the halo magnetic null region near the anode which might be exploited to improve performance. As a result of the research presented, design changes are suggested for future iterations. In its current embodiment, the thruster already offers advantages over heritage small satellite EP systems, and is a viable candidate for near-term industrialisation.

Styles APA, Harvard, Vancouver, ISO, etc.

22

Hickernell, Thomas Slocum. "Statistical decision making with a dual detector probe." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184538.

Texte intégral

Résumé :

Conventional imaging techniques for cancer detection have difficulty finding small, deep tumors. Single-detector radiation probes have been developed to search for deep lesions in a patient who has been given a tumor-seeking radiopharmaceutical. These probes perform poorly, however, when the background activity in the patient varies greatly from site to site. We have developed a surgical dual-detector probe that solves the problem of background activity variation, by simultaneously monitoring counts from a region of interest and counts from adjacent normal tissue. A comparison of counts from the detectors can reveal the class of tissue, tumor or normal, in the region of interest. In this dissertation we apply methods from statistical decision theory and derive a suitable comparison of counts to help us decide whether a tumor is present in the region of interest. We use the Hotelling trace criterion with a few assumptions to find a linear discriminant function, which can be reduced to a normalized subtraction of the counts for large background count-rate variations. If area under the ROC curve is our figure of merit, the likelihood ratio is the optimum discriminant. We model likelihood functions of the data given the "tumor" and "no-tumor" hypotheses, and calculate the likelihood ratio. Using a spatial response map of the dual probe, a computer torso phantom, and estimates of activity distribution, we simulate a surgical staging procedure to test the dual probe and the discriminant functions. Results of the simulations show that the dual probe effectively solves the problem of background activity variations when used with any of the discriminant functions derived in this dissertation.

Styles APA, Harvard, Vancouver, ISO, etc.

23

Barnard, Marinus. "Diagnostic utility of the line probe assay for the detection of drug resistance in Mycobacterium tuberculosis." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/79807.

Texte intégral

Résumé :

Thesis(PhD)--Stellenbosch University, 2013. ENGLISH ABSTRACT: The epidemic levels of drug-resistant tuberculosis (DR-TB) in high-burden countries such as South Africa, which is currently ranked as third highest in the world, is the result of a synergistic relationship between the increased transmission of DR strains, poor patient adherence as well as Human-Immunodeficiency Virus (HIV)-coinfection. The impact of these combined factors on the rise of DR-TB led to an urgent need for the development of new diagnostic tools to rapidly detect TB and its associated drug susceptibility profile. The Foundation for Innovative New Diagnostics (FIND) has taken the onus upon them to ensure that laboratory strengthening becomes a reality by having developed, and still developing, new diagnostic assays in order to improve the laboratory turn-around time (TAT), whereby the transmission of DR-TB strains can be stopped. Laboratory strengthening does not solely rely on new diagnostic assays alone, and thus a Quality Management System, discussed in the dissertation, must be in place to ensure that the rapid result is accurate and reliable. The series of studies encompassed in this dissertation includes methodological validations (both technical and operational) of rapid TB diagnostic assays in order to rapidly and accurately diagnose the disease, and thus reducing the diagnostic delay associated with conventional diagnostic platforms. The studies were conducted “in-house” at the National Health Laboratory Service (NHLS) Reference TB laboratory in Green Point, Cape Town, which is a high-volume public health laboratory. The need to rapidly detect resistance to the first line anti-tubercular drugs Isoniazid and Rifampicin was a priority and thus the performance of a commercial line probe assay (LPA), the GenoType®MTBDRplus Ver1.0 LPA, was assessed for use on smear positive direct patient material. The performance characteristics was superior to that of conventional drug susceptibility testing, where the sensitivity and specificity for the detection of multi-drug resistant TB (MDR-TB) was 98.8 and 100%, respectively, with results in 1-2 days. Based on this study, the World Health Organization (WHO) endorsed the use of molecular LPA for the rapid detection of DR-TB. Furthermore, the need for quality assurance associated with the GenoType®MTBDRplus LPA in the diagnostic laboratory is essential and thus a user manual for the molecular detection of Drug Resistant Tuberculosis in resource-limited settings has also been developed (http://www.finddiagnostics.org/export/sites/default/resource-center/reports brochures/docs/LPA LaboratoryManual22Mar2012.pdf) for which Global Laboratory Initiative (GLI) status is pending. With the outbreak of extensively drug resistant TB (XDR-TB) in Tugela Ferry area in KwaZulu-Natal and the rest of the world, the need to rapidly detect resistance to the second line drugs arose, and thus the performance characteristics of the GenoType®MTBDRsl LPA was assessed for use on smear positive direct patient material. The performance characteristics proved to be excellent once again, with a 93.3% reduction in TAT. The data was scrutinized by the WHO, where it may be used as a triage test to guide treatment, but to date, no final policies on the use thereof has been finalized. The need for rapid point-of-care (POC) testing led to the implementation of the Xpert®MTB/RIF assay in the referral laboratories, for use on both smear positive and smear negative direct patient material. In order to accommodate for laboratories where the LPA has been implemented already, the GenoType®MTBDRplus Ver2.0 LPA was developed, which is aimed for use on all smear types as well. A head-to-head assessment was done between these assays to determine their performance characteristics and it was shown to be equally good. In this study we have shown the utility of molecular diagnostic assays to rapidly diagnose TB and its associated drug susceptibility patterns. This will have a significant impact on diagnostic delay and clinical decision making as well as patient outcome. AFRIKAANSE OPSOMMING: Die epidemiese vlakke van middel-weerstandige tuberkulose (MW-TB) in hoë-lading lande, soos Suid Afrika wat tans derde hoogste op die wêreld ranglys is, is die nagevolge van 'n sinergistiese verband tussen die verhoogde voorkoms van transmissie van MW stamme, swak pasiënt deelname aan die voorgeskrewe behandelings programme, asook Menslike Immuniteitsgebreksvirus (MIV) ko-infeksie. Die impak van hierdie drie faktore saam, gee aanleiding tot 'n verhoging in MW-TB en dus was daar 'n daadwerklike behoefte vir die ontwikkeling van nuwe diagnostiese toetse wat nie net TB kan identifiseer nie, maar wat ook die gepaardgaande middel-weerstandigheids profiel aandui. Die “Foundation for Innovative New Diagnostics” (FIND) het die onus van laboratorium versterking op hulself geneem, deur te verseker dat die nuut ontwikkelde diagnostiese toetse, asooks steeds ontwikkelende diagnostiese toetse, gebruik kan word om die konsep van laboratorium versterking 'n realiteit te maak. Die doel is dus om sodoende die tyd-tot-resultaat tussen geneesheer en laboratorium te verbeter, terwyl die transmissie van MW-TB ook die hok geslaan kan word. Nietemin, laboratorium versterking berus nie net op nuwe diagnostiese toetse nie, en dus is dit noodsaaklik dat 'n Kwaliteitbestuursisteem, soos bespreek in hierdie verhandeling, in plek is om te verseker dat die resultaat spoedig, akkuraat en betroubaar is. Die samevattende reeks studies in hierdie verhandeling behels metodologiese validasies (beide tegnies en operasioneel van aard) van spoedige TB diagnostiese toetse met die doel om die siekte so vinnig en akkuraat as moontlik te diagnoseer en dus die diagnostiese vertraging, wat histories met konvensionele metodes geassosiëerd is, te verminder. Al die studies is uitgevoer in die “National Health Laboratory Service (NHLS)” TB verwysingslaboratorium in Groenpunt, Kaapstad, wat 'n hoë-volume publieke gesondheidslaboratorium is. Die noodsaaklikheid om weerstandigheid teenoor die eerste-linie antituberkulose middels isoniasied en rifampisien so spoedig moontlik te diagnoseer het 'n groot bekommernis geword, en dus is die laboratorium daartoe genoop om die prestasie eienskappe van 'n kommersiëel beskikbare “line probe assay” (LPA), die “Genotype®MTBDRplus Ver1.0 LPA”, te asseseer vir die gebruik daarvan op direkte pasientmateriaal wat smeer positief is. Die prestasie eienskappe was beter as die van konvensionele middelvatbaarheidstoetse, waar die sensitiwiteit en spesifisiteit vir die diagnosering van MW-TB 98.8 en 100%, respektiewelik, was. Verder was die resultate ook binne 1-2 dae beskikbaar. Op grond van dié bevindinge het die Wêreldgesondheidsorganisasie (WGO) die gebruik van hierdie molekulêre “LPA” vir die spoedige diagnose van MW-TB onderskryf. Nietemin, die belangrikheid van gehalteversekering wat met die “GenoType®MTBDRplus LPA” in die diagnostiese laboratorium geassosieerd is, is essentiëel en dus is 'n gebruikershandleiding vir die molekulêre diagnose van MW-TB in beperkte hulpbron-instellings ontwikkel (http://www.finddiagnostics.org/export/sites/default/resource-center/reports brochures/docs/LPA LaboratoryManual22Mar2012.pdf) waarvoor daar op„n “Global Laboratory Initiative (GLI)” status in afwagting is. Met die uitbraak van ekstensiewemiddelweerstandige TB (EMW-TB) in die Tugela Ferry distrik in KwaZulu-Natal asook in die res van die wêreld, het die noodsaaklikheid onstaan om weerstandigheid teenoor die tweede-linie middels ook so spoedig moontlik te diagnoseer, en die laboratorium is dus weereens daartoe genoop om die prestasie eienskappe van die “GenoType®MTBDRsl LPA” (ook vir die gebruik op direkte pasient materiaal wat smeer positief is) te asseseer. Die prestasie eienskappe was weereens verbysterend, en het „n 93.3% afname in tyd-tot-resultaat getoon. Die data is deur die WGO aangevra, en daar is besluit dat die toets gebruik kan word om behandeling in werking te stel, maar geen finale onderskrywings is tot op hede nog gemaak nie. Die behoefte aan 'n punt-van-sorg toets het gelei tot die implementering van die “Xpert®MTB/RIF” toets in die verwysingslaboratorium, en is geoogmerk vir die gebruik op beide smeer positiewe en -negatiewe direkte pasient materiaal. Omrede die “LPA” al in verskeie laborotoriums geimplementeer was, is die “GenoType®MTBDRplus Ver2.0 LPA” ontwikkel, waarvan die gebruik onafhanklik is van die smeerresultaat. 'n Direkte assesering tussen die twee toetse was gedoen en daar is bevind dat beide se prestasie eienskappe vergelykend was. In hierdie studies het ons bewys dat die gebruik van molekulêre diagnostiese toetse in staat is om TB en die gepaargaande middel-weerstandigheids profiel spoedig te diagnoseer. Hierdie bevindinge sal 'n groot impak hê op die vetraging van tyd-tot-resultaat, op die mediese besluitneming asook op die uitkoms van die pasiënt. FIND (Foundation for Innovative New Diagnostics) Hain Lifescience National Health Laboratory Service (NHLS)

Styles APA, Harvard, Vancouver, ISO, etc.

24

Rajabian, Mahmoud. "Diagnostic study of low pressure supersonic DC plasma jets by emission spectroscopy and enthalphy probe techniques." Thèse, Université de Sherbrooke, 2001. http://savoirs.usherbrooke.ca/handle/11143/1728.

Texte intégral

Résumé :

In this work, the characteristics of plasma jets produced by a commercial DC plasma spray torch connected to a controlled pressure chamber are investigated. The plasma gas employed is a mixture of argon, nitrogen and hydrogen with the initial gas flow rates of 40, 10, and 1 SLPM respectively. The plasma torch is operated at chamber pressures of 6.5, 13, 26, 39, 53 and 101 kPa and a fixed input power of 17.5 kW. Optical emission spectroscopy is used to measure the temperatures and electron density profiles. The measurements of temperature are carried out by means of a Boltzmann plot of several isolated argon atom spectral lines. The electron density is measured from the Stark broadening of the H[subscript bêta] line 486.1 nm and the continuum emissivity. Partially resolved spectra of the N[subscript 2]+ molecular band are used for the rotational temperature evaluation. The rotational emission from the (0,0) band of the first negative system is compared to synthetic spectra to evaluate the rotational temperature within the flow field. Finally, the measurements of the gas kinetic temperature and the plasma velocity are performed by the enthalpy probe technique. The experimental results show the occurrence and the position of the different gas dynamics zones; i.e., supersonic expansion, stationary shock front and subsonic relaxation at low pressures (less than 40 kPa). The plasma flow is accelerated to its maximum velocity at the expansion where a minimum in the electron density and temperature is observed. At the end of the expansion a stationary shock front occurs at 4, 8, 12, and 15 mm downstream from the nozzle exit at pressures 39, 26, 13 and 6.5 kPa respectively. The electron density profiles show the variations along the plasma axis that coincide with the position of the shock waves. Good agreement between the electron density results obtained from the Stark broadening and from the continuum emissivity is observed. Enthalpy probe measurements on gas kinetic temperature and plasma velocity reveal the general features of low pressure plasma jets, i.e., higher flow velocity and longer heating zone of expanded plasma with lower temperature. The measurements also coincide with the rotational temperature obtained from emission spectroscopy. The temperature results confirm that the local thermodynamic equilibrium LTE exists at pressures of 100 and 53 kPa. However, at lower pressures where the supersonic shock waves are formed, the slow energy exchange between the heavy and light particles leads to significant deviations from the LTE especially in the shock region.

Styles APA, Harvard, Vancouver, ISO, etc.

25

Cheng, Wing-suen, and 鄭穎璿. "Rapid diagnosis of isoniazid resistant mycobacterium tuberculosis by hybridization probe based real time PCR." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B4833361X.

Texte intégral

Résumé :

Background Tuberculosis (TB) infection is a contagious disease due to infection by Mycobacterium tuberculosis(MTB) causing global health burden. There is increasing effort to develop early case detection methods and also to address the issue of multidrug resistance TB (MDR-TB). Molecular methods have been applied to provide rapid and accurate diagnosis. In addition to commercial kits being available for the detection of MTB from clinical specimens, In-house PCR assays have also been developed for the detection of MTB, and can be adjusted according to the laboratories’ own demand. Several molecular techniques like TaqMan probes and Hybridization probes may be applied to target for markers of MTB, e.g. 16s rRNA and IS6110.Detection of the mutation genes, for example, katGfor isoniazid (INH), enables determination of susceptibility of the antibiotic more rapidly than traditional culture methods, and is especially useful due to the increasing emergence of MDR-TB. A wide range of genes have been reported to be related to the resistance of INH, katG315 mutation is the most common gene among them. Therefore, genotyping katG315 allows determination of the susceptibility of INH. Objective The first objective is to evaluate the diagnostic performance of IS6110 One-tube Nested Real-Time PCR for the detection of MTB. Clinical pulmonary specimens collected from Tuen Mun Hospital were retrieved for investigation. All the specimens have already been tested for COBAS TaqMan MTB test and culture results have been obtained for all the samples. During the first stage of the study, all the specimens were tested with IS6110 One-tube Nested Real-Time PCR. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic odds ratio were obtained from the comparison with the gold standard of MTB detection, i.e., culture. During the second stage of the study, samples were selected to undergo katG315 HybProbe Real-Time PCR assay to determine the genotype of katG. The performance of the assay was evaluated statistically. Result In the first stage of the study, 200 samples were tested with IS6110 One-tube Nested Real-Time PCR. The assay was found to have a sensitivity of 76.92%, specificity of 98.52%, positive predictive value of 96.15%, negative predictive value of 89.86% and the diagnostic odds ratio of 221.667. In the second stage of the study, 66 samples were selected and tested for katG315 HybProbe Real-Time PCR assay, 36 samples were successfully genotyped while 30 samples failed to be genotyped. The only culture proven INH resistance specimen was not amplified at first, and culture isolate was extracted for genotyping again. The repeated test confirmed the genotype of the resistance strain to be a mutant. Conclusion katG315 HybProbe Real-Time PCR assay is a valid approach for genotyping katG. However, the sensitivity and efficiency has to be improved before application for clinical use. From the statistics obtained, COBAS TaqMan PCR assay, which is routinely used in Tuen Mun Hospital, is statistically proven to have comparatively better performance than the IS6110 One-tube Nested Real-Time PCR. Improvement on the assay is required for IS6110 One-tube Nested Real-Time PCR. However, there is great potential of applying both IS6110 One-tube Nested Real-Time PCR and katG315 HybProbe Real-Time PCR assay in clinical use with the same platform available. published_or_final_version Microbiology Master Master of Medical Sciences

Styles APA, Harvard, Vancouver, ISO, etc.

26

Van, Aspert-Van Erp Anniek. "Néoplasie intraépithéliale des cellules columnaires endocervicales (ECCIN) : caractères cytomorphologiques et qualité du diagnostic." Université Joseph Fourier (Grenoble), 1995. http://www.theses.fr/1995GRE19007.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

27

Ratushna, Vladyslava G. "Incorporation of Physico-Chemical Parameters Into Design of Microarray Experiments." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/32989.

Texte intégral

Résumé :

Microarrays containing long oligonucleotides provide sensitive and specific detection of gene expression and are becoming a popular experimental platform. In the process of designing an oligonucleotide microarray for Brucella, we optimized the overall design of the array and created probes to distinguish among the known Brucella species. A 3-way genome comparison identified a set of genes which occur uniquely in only one or two of the sequenced Brucella genomes. Reverse transcriptase PCR assays of over one hundred unique and pairwise-differential regions identified in Brucella revealed several groups of genes that are transcribed in vivo with potential significance for virulence. The structural and thermodynamic properties of a set of 70mer oligonucleotide probes for a combined B. abortus, B. melitensis and B. suis microarray were modeled to help perform quantitative interpretation of the microarray data. Prediction and thermodynamic analysis of secondary structure formation in a genome-wide set of transcripts from Brucella suis 1330 demonstrated that properties of the target molecule have the potential to strongly influence the rate and extent of hybridization between transcript and an oligonucleotide probe in a microarray experiment. Despite relatively high hybridization temperatures used in the modeling process, parts of the target molecules are predicted to be inaccessible to intermolecular hybridization due to the formation of stable intramolecular secondary structure. Features in the Brucella genomes with potential diagnostic use were identified, and the extent to which target secondary structure, a molecular property which is not considered in the array design process, may influence the quality of results was characterized. Master of Science

Styles APA, Harvard, Vancouver, ISO, etc.

28

Parnell, Harriet. "Towards a Ge-Sb-Se/S hyperspectral imaging probe for early cancer diagnosis." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/53605/.

Texte intégral

Résumé :

Owing to their vitreous nature and mid-infrared (MIR) transparency, chalcogenide glasses are a promising material for remote hyperspectral imaging. For medical applications, such as in-vivo cancer diagnosis, Ge-Sb-Se glasses are a particularly interesting material since, it is believed that Sb-containing chalcogenides are less toxic than their As-containing equivalents. For passive optical fibres which aim to deliver and collect MIR light to and from tissue samples, the main challenge which faces their performance is the removal of extrinsic optical losses. Hence, this Project explores and develops high purity Ge-Sb-Se/S bulk glasses and optical fibres. Focussing on the GexSb10Se90-x atomic % (at. %) glass series, bulk samples are initially characterised before the fibre-drawing capability of each composition is assessed. Although stoichiometric Ge25Sb10Se65 at. % and non-stoichiometric Ge20Sb10Se70 at. % glasses both exist within the same two-dimensional, overconstrained network, results from their fibre-drawing investigations reveal a significant difference in their resistance against crystallisation. Whereas, non-stoichiometric Ge20Sb10Se70 at. % is shown to produce stable optical fibres with promising low losses, it is found that stoichiometric Ge25Sb10Se65 at. % repeatedly crystallises into a single phase of monoclinic GeSe2. To produce a low numerical aperture (NA) step-index fibre (SIF), it is suggested that a Ge20Sb10Se70 at. % core glass is paired with a Ge20Sb10Se67S3 at. % cladding glass. Substituting 3 at. % Se for 3 at. % S in the Ge20Sb10Se70-xSx at. % series, is found to increase the glass transition temperature (Tg) by 10 °C and decrease the refractive index by 0.01. It is calculated, that for a SIF consisting of a Ge20Sb10Se70 at. % core and a Ge20Sb10Se67S3 at. % cladding, the NA would be 0.25 at 3.1 µm wavelength. Co-extruded at 267±0.1 °C, and then subsequently drawn into 200 ±5 µm diameter SIF, optical loss measurements demonstrate that MIR light can be successfully guided through a large, circular Ge20Sb10Se70 at. % core. The core-cladding ratio is found to be 95 %. Calculations using the Antoine equation are used to investigate the optimal conditions required for the bake-out of Se, S and Sb impurities prior to batching. For a high-purity Ge20Sb10Se70 at. % core glass, a distillation technique is developed using 1000 ppm wt. TeCl4 as a hydrogen getter [H] and 700 ppm wt. Al as an oxygen getter [O]. It is shown, that to successfully distil Ge-Sb-Se glass, with [H] and [O] getters, two primary challenges must be overcome. The first suggests that there must be sufficient removal of HCl(g), prior to the start of distillation, in order to avoid a vapour barrier once the silica glass distillation rig is sealed. The second advises precise temperature control, with necessary monitoring, so that there is no separation of Ge-Sb-Se material, either before or after it has distilled. Successful distillation is eventually achieved in an open system i.e. under flowing vacuum, at a temperature close to 693 °C. Optical fibre loss measurements, conducted on 18 m length of 200 ±10 µm diameter fibre, reveal that the distillation of Ge20Sb10Se70 at. % core glass with 1000 ppm wt. TeCl4 and 700 ppm wt. Al, removes the Ge-O absorption peak at 7.9 µm and significantly reduces, if not removes, all of the Se-H peaks as well. The lowest background loss is also found as 0.44 dB/m at 6.4 µm wavelength. As a preliminary investigation into the biocompatibility of Ge-Sb-Se glasses for medical applications, two in-vitro cytotoxicity test are explored viz.: a direct contact protocol with an alamarBlue® assay and an elution protocol with a neutral red assay. Due to contradictory results between Trial 1 and Trial 2, it is suggested that further work is required to confirm the cytotoxicity of etched vs. non-etched Ge-Sb-Se fibres. Overall, there has been significant progress made during this Project, towards the fabrication of high purity Ge-Sb-Se/S SIFs for use in a MIR imaging probe for early cancer diagnosis.

Styles APA, Harvard, Vancouver, ISO, etc.

29

Li, Jichun. "Tissue diagnosis probe based on stiffness measurement using vision and force sensing modalities." Thesis, King's College London (University of London), 2013. https://kclpure.kcl.ac.uk/portal/en/theses/tissue-diagnosis-probe-based-on-stiffness-measurement-using-vision-and-force-sensing-modalities(2157fcfd-4155-43c8-ab70-2d8fad7ee622).html.

Texte intégral

Résumé :

This thesis presents the creation of a novel tissue diagnosis probe based on the measurement of stiffness and force during mechanical tool-tissue interactions. The probe using force and vision sensing modalities was created to be used for tissue diagnosis in medical applications, especially for robot-assisted minimallyinvasive surgery (MIS) to provide the necessary sensing modalities to allow for haptic feedback. By employing the developed prototypes, estimations of the mechanical properties of ex-vivo human prostate tissues were conducted using the finite element analysis (FEA) method and the Newton-Raphson algorithm. A clinical study of prostate tumour identification has been carried out on ex-vivo prostate samples and a study onrobotic palpation using a second prototype developed as part of this projectand comparing it to manual palpation was conducted. With the aim of measuring the indentation depth and the corresponding tissue reaction force simultaneously to obtain stiffness information,aprototype of a stiffness probe was constructedconsisting of a commercial digitalcamera and a force sensor. The effectiveness and sensitivityof the designedprobe was validatedthrough experiments on silicone phantomsand animal organs. The results showed that the probe could perform stiffness measurementsand localize tissue abnormalitieswhen indenting or sliding over the target surfaces. In order to investigate the mechanical properties of ex-vivo human prostate using the developed probe, a portable sliding indenter robot integrating the probe and the Phantom Omni device was created. Based on force-displacement measurements of the probe-soft tissue interaction, inversefinite element analysis (FEA)andthegeneralised Newton-Raphson algorithm were used to estimateunknown parameters including the shear modulus ofthe ex-vivo human prostate. The prostate was modelled as a nonlinear hyperelastic material (utilizing Arruda-Boyce model) inthe finite element modelling software package, ABAQUS 6.8-1. The results indicated that the proposed model can estimate the mechanical properties ofthe ex-vivo human prostate effectively. With the aim of identifying the stiffness of normal and cancerous prostate tissue, the prostates of 26 male patients were examinedusing the developed sliding indenter robot. Threedimensional (3D) stiffness maps of ex-vivo human prostate were created. The stiffness maps were correlatedwith other clinical examinations including Magnetic Resonance Imaging (MRI), Digital Rectal Examination (DRE), histology and Ultrosound-guided biopsy. The proposedprobe proved to be a promising platform to distinguish between cancerous and healthy tissue in prostate andto discriminate pathological tissue variations. In addition, the results provided quantitative information for the diagnosis and localization of prostate cancer. To ensure the proposed probe is suitable for MIS applications, a furtherprototype of the stiffness probebased on optic-fibreforce sensing replacing the commercial available force sensor was created. A study on robotic palpation using the developed probe and comparing it tomanual palpation was conducted. The results indicated that robotic palpation was more effective than manual palpation conducted by experienced surgeons.

Styles APA, Harvard, Vancouver, ISO, etc.

30

Welzel, Thomas. "Time-resolved characterisation of pulsed magnetron discharges for the deposition of thin films with plasma diagnostic methods." Doctoral thesis, Universitätsbibliothek Chemnitz, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-81968.

Texte intégral

Résumé :

Research on the characterisation and understanding of pulsed magnetron discharges used for the deposition of thin, especially dielectric, films has been carried out between 2003 and 2008 at Chemnitz University of Technology. This thesis is a collection and summary of the original research during this period. In the main part of the thesis, work published in peer-reviewed scientific papers is summarised and yet unpublished results are given in more detail. Different aspects highlighted in the publications are described in a general context of the characterisation of the pulsed discharges for the principal understanding. The cross-linking of the published results is addressed and where necessary extensions to the publications are given. The main part is organised in three sections. In the first one, basics of pulsed magnetron discharges, their application, and important questions are summarised. The second section describes general results and physics of the discharges that have been obtained during the research work. It also emphasises the successful development or modifications of experimental techniques for the time-resolved characterisation. The third section addresses the possibilities to modify and control the process by external parameters that are typically accessible during the application or required by it. An appendix to the thesis comprises selected published research work which is made available as reprints of the original publications. Other publications which are not included as reprints are referenced to in the main part Untersuchungen zur Charakterisierung und zum Verständnis gepulster Magnetronentladungen, die zur Abscheidung von dünnen Schichten, besonders von dielektrischen Schichten, verwendet werden, wurden in den Jahren 2003 bis 2008 an der Technischen Universität Chemnitz durchgeführt. Diese Arbeit ist eine Sammlung und Zusammenfassung von neuen Forschungsergebnissen, die in diesem Zeitraum gewonnen wurden. Im Hauptteil der Habilitationsschrift werden die Arbeiten, die in referierten wissenschaftlichen Zeitschriften erschienen sind, zusammengefasst und noch unveröffentlichte Ergebnisse ausführlicher beschrieben. Verschiedene Aspekte, die in den Veröffentlichungen herausgestrichen wurden, werden in einem allgemeinen Zusammenhang der Charakterisierung gepulster Entladungen für ein prinzipielles Verständnis dargestellt. Querverbindungen zwischen den veröffentlichten Ergebnissen werden herausgearbeitet und wo nötig werden Erweiterungen der Originalveröffentlichungen vorgenommen. Der Hauptteil der Habilitationsschrift ist in drei Abschnitte unterteilt. Im ersten Teil werden Grundzüge gepulster Entladungen, ihre Anwendung und wesentliche Fragestellungen zusammengefasst. Der zweite Abschnitt beschreibt allgemeine Ergebnisse und die Physik der Entladungen, die während der Forschungsarbeit herausgearbeitet wurden. Er stellt auch die erfolgreiche Neuentwicklung oder Modifikation von Messtechniken zur zeitaufgelösten Charakterisierung heraus. Der dritte Abschnitt befasst sich mit den Möglichkeiten, den Beschichtungsprozess durch externe Parameter, die typischerweise während der Prozessanwendung zugänglich oder auch erforderlich sind, zu modifizieren und zu steuern. Der Anhang der Schrift beinhaltet ausgewählte Originalveröffentlichungen, die in Form von Reprints zugänglich gemacht werden. Andere Veröffentlichungen, die nicht im Anhang enthalten sind, werden im Hauptteil zitiert

Styles APA, Harvard, Vancouver, ISO, etc.

31

Welzel, Thomas. "Time-resolved characterisation of pulsed magnetron discharges for the deposition of thin films with plasma diagnostic methods." Doctoral thesis, Universitätsbibliothek Chemnitz, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-201000922.

Texte intégral

Résumé :

Research on the characterisation and understanding of pulsed magnetron discharges used for the deposition of thin, especially dielectric, films has been carried out between 2003 and 2008 at Chemnitz University of Technology. This thesis is a collection and summary of the original research during this period. In the main part of the thesis, work published in peer-reviewed scientific papers is summarised and yet unpublished results are given in more detail. Different aspects highlighted in the publications are described in a general context of the characterisation of the pulsed discharges for the principal understanding. The cross-linking of the published results is addressed and where necessary extensions to the publications are given. The main part is organised in three sections. In the first one, basics of pulsed magnetron discharges, their application, and important questions are summarised. The second section describes general results and physics of the discharges that have been obtained during the research work. It also emphasises the successful development or modifications of experimental techniques for the time-resolved characterisation. The third section addresses the possibilities to modify and control the process by external parameters that are typically accessible during the application or required by it. An appendix to the thesis comprises selected published research work which is made available as reprints of the original publications. Other publications which are not included as reprints are referenced to in the main part Untersuchungen zur Charakterisierung und zum Verständnis gepulster Magnetronentladungen, die zur Abscheidung von dünnen Schichten, besonders von dielektrischen Schichten, verwendet werden, wurden in den Jahren 2003 bis 2008 an der Technischen Universität Chemnitz durchgeführt. Diese Arbeit ist eine Sammlung und Zusammenfassung von neuen Forschungsergebnissen, die in diesem Zeitraum gewonnen wurden. Im Hauptteil der Habilitationsschrift werden die Arbeiten, die in referierten wissenschaftlichen Zeitschriften erschienen sind, zusammengefasst und noch unveröffentlichte Ergebnisse ausführlicher beschrieben. Verschiedene Aspekte, die in den Veröffentlichungen herausgestrichen wurden, werden in einem allgemeinen Zusammenhang der Charakterisierung gepulster Entladungen für ein prinzipielles Verständnis dargestellt. Querverbindungen zwischen den veröffentlichten Ergebnissen werden herausgearbeitet und wo nötig werden Erweiterungen der Originalveröffentlichungen vorgenommen. Der Hauptteil der Habilitationsschrift ist in drei Abschnitte unterteilt. Im ersten Teil werden Grundzüge gepulster Entladungen, ihre Anwendung und wesentliche Fragestellungen zusammengefasst. Der zweite Abschnitt beschreibt allgemeine Ergebnisse und die Physik der Entladungen, die während der Forschungsarbeit herausgearbeitet wurden. Er stellt auch die erfolgreiche Neuentwicklung oder Modifikation von Messtechniken zur zeitaufgelösten Charakterisierung heraus. Der dritte Abschnitt befasst sich mit den Möglichkeiten, den Beschichtungsprozess durch externe Parameter, die typischerweise während der Prozessanwendung zugänglich oder auch erforderlich sind, zu modifizieren und zu steuern. Der Anhang der Schrift beinhaltet ausgewählte Originalveröffentlichungen, die in Form von Reprints zugänglich gemacht werden. Andere Veröffentlichungen, die nicht im Anhang enthalten sind, werden im Hauptteil zitiert

Styles APA, Harvard, Vancouver, ISO, etc.

32

Usoltceva, Mariia. "Advancements in Langmuir probe diagnostic for measurements in RF sheath and in modelling of the ICRF slow wave." Electronic Thesis or Diss., Université de Lorraine, 2019. http://www.theses.fr/2019LORR0061.

Texte intégral

Résumé :

Injecter de la puissance au plasma avec les ondes au voisinage de la fréquence cyclotron ionique (ICRF) est une technique prometteuse pour chauffer les plasmas de tokamak aux températures de fusion requises. Pour le rendement élevé, l'antenne ICRF doit être placée à proximité du plasma, mais ils accroissent les interactions plasma-paroi néfastes. Les ions accélérés par le champ électrique dans la gaine radiofréquence (RF) se sont avérés être à l'origine de ces interactions. La conception de l'antenne ICRF pourrait être optimisée pour réduire les effets observés. Ces études peuvent être réalisées sur une simple expérience dédiée. Aline (A Linear Experiment) est une machine linéaire avec un plasma cylindrique à basse température que s'appuie sur la caractérisation du plasma avec la sonde de Langmuir. Le champ magnétique modifie complètement le transport de particules dans le plasma. Par conséquent, les méthodes classiques d'analyse de sondes ne sont plus applicables. Cela est particulièrement vrai pour une sonde de Langmuir cylindrique de petit diamètre parallèle au champ magnétique ou avec un petit angle avec celui-ci. Les théories développées pour le traitement des données de la sonde de Langmuir pour le plasma magnétisé sont présentés. Les résultats sont comparés aux densités obtenues par interférométrie. Les techniques d'analyse des données présentées sont non seulement importantes pour l'application sur Aline, mais aussi pour d’autre machines à plasma magnétisé. IShTAR (Ion cyclotron Sheath Test Arrangement) fournit des conditions plus proches de celles du tokamak que celles d'Aline car possédant une antenne ICRF imitant celles d'un tokamak. L'objectif est d'étudier la propagation des ondes ICRF dans la configuration IShTAR. Les diagnostics de sonde ont été utilisés pour quantifier les paramètres plasma et les champs des ondes ICRF pertinents. Des simulations numériques de l'onde lente ICRF ont été réalisées à COMSOL. Le plasma a été mis en œuvre en tant que matériau avec des propriétés physiques ajustées manuellement. Les structures de champ obtenues pour l'onde lente diffèrent significativement de celles de l'onde rapide (autre solution de la relation de dispersion), et présentent une forte dépendance du profil de densité sur le bord du plasma. Les résultats de cette thèse contribuent aux études de la physique de la gaine RF sur des dispositifs linéaires dédiés, ainsi que de la physique des ondes ICRF sur le bord du plasma du tokamak en général Coupling power to the plasma with ion cyclotron range of frequencies (ICRF) waves is a promising method for heating tokamak plasmas to fusion relevant temperatures. For high efficiency, the ICRF antenna must be placed close to the plasma, but they enhance destructive plasma-wall interactions. Plasma ions accelerated by the electric field in the radio-frequency (RF) sheath have been found to be the main cause of these interactions. The ICRF antenna design could be optimized to reduce the observed effects. The physics of these effects can be studied on a simple specially designed experiment. Aline (A LINear Experiment) is a linear low-temperature plasma device. The machine is focused on plasma characterization with the Langmuir probe diagnostic. The presence of magnetic field changes completely the particle transport in plasma, therefore conventional methods of data analysis are not applicable. Especially it is true for a small cylindrical Langmuir probe parallel to the magnetic field or at a small angle to it. In this thesis theories are presented which were developed for Langmuir probe data processing for magnetized plasma. The first results are also presented, as well as a comparison to line-averaged densities by interferometry. Presented data analysis techniques are not only important for application on Aline but can be used on any machine with magnetized plasma. IShTAR (Ion cyclotron Sheath Test Arrangement) is closer to tokamak conditions than Aline because it has an ICRF antenna which mimics tokamak antennas. In the framework of this thesis the objective is to study comprehensively the ICRF wave propagation in IShTAR configuration. Probe diagnostics were employed to quantify the relevant plasma parameters and the relevant ICRF wave fields. Numerical simulations of the ICRF slow wave were done in COMSOL. Plasma was implemented as a material with manually assigned physical properties. Field structures obtained for the slow wave differ significantly from the other mode, fast wave, and exhibit strong dependence on the density profile on the plasma edge. The results of this thesis work contribute to the studies of the RF sheath physics on dedicated linear devices, as well as the physics of ICRF waves on the tokamak plasma edge in general. In ICRF simulations for tokamak devices the slow wave propagation on the edge is avoided. Results of this thesis can be used to improve the complex tokamak ICRF simulations

Styles APA, Harvard, Vancouver, ISO, etc.

33

Khireddine, Saïd. "Modélisation neuronale et diagnostic en champ proche des dispositifs coplanaires : Application aux filtres à temps de groupe plat." Rennes, INSA, 2005. http://www.theses.fr/2005ISAR0006.

Texte intégral

Résumé :

Ces travaux de recherche abordent, dans un premier temps, l'utilisation de l'approche neuronale pour la modélisation des discontinuités coplanaire. Les modèles neuronales développés sont obtenus grâce à un apprentissage de leurs réseaux de neurones avec un ensemble de données de simulation EM. Après validation, les modèles générés sont ensuite intégrés par le biais de relation équationnelle dans un outil de CAO et ont permis la création de librairie coplanaire. Le temps de calcul nécessaire à la simulation est quasi instantané et ceci avec une précision égale à celle d'une simulation EM. L'approche est également étendue à la modélisation de dispositifs non-linéaire (un déphaseur et un atténuateur). La deuxième partie est consacrée aux filtres coplanaires miniatures à temps de groupe plat. L'effet de miniaturisation est obtenu par la modification de la géométrie du stub conventionnel, où l'effet capacitif est généré le long de la ligne coplanaire rendant la structure finale plus compacte. L'amélioration du temps de groupe est ensuite obtenue en utilisant l'approche absorptive. Elle est basée sur l'emplacement optimal de charges résistives à l'intérieur des filtres permettant ainsi de donner une réponse de type quasi-gaussienne. De plus, l'adaptation est pratiquement assurée au moins jusqu'à la fréquence de coupure du filtre non chargé. Des mesures systèmes à 10 et 12. 5Gb/s sont effectuées afin de quantifier les performances de ces filtres dans l'amélioration du diagramme de l'œil. La technique de caractérisation en champ proche est enfin proposée pour le diagnostic des filtres réalisés, afin d'avoir une cartographie de la distribution spatiale du champ proche. La mesure est assurée à l'aide d'un système à sonde, type monopole, qui permet de récolter la composante normale du champ au-dessus du circuit sous test. Les images EM obtenues ont permis de mettre en valeur l'effet des fils de pontage et leurs importances pour le bon fonctionnement des structures coplanaires. These research works deal in first with the use of the neuronal network approach to modelize coplanar discontinuities. The neural model is developed by teaching or training a neural network with a set of EM simulation data. After validation, these generated models are then integrated in CAD tool under equation form, and allow creating a coplanar library. The simulation necessary computing time is quasi instantaneous and this with a precision equal to the EM simulation. The approach is also extended to modelling the non-linear devices (attenuator and phase shifter). A second part treats about miniature coplanar filters with flat group delay. The miniaturisation is obtained by modifying the geometry of the conventional stub, where the capacitive effect is generated along the coplanar main line making the final structure more compact. The improvement of the group delay is obtained by using the absorptive approach. It is based on the optimal position of resistive loads inside the filters which allow giving a quasi-Gaussian response. Moreover, the adaptation is practically ensured until the cut-off frequency of the unloaded filter. System measurements at 10 and 12. 5Gb/s are realized in order to quantify the performances of these filters in the improvement of the eye diagram. The near-field characterization technic is finally proposed to diagnose the realized filters, in order to obtain cartography of the spatial distribution of the near fields. Measurements are ensured using a probe system, a monopole standard, which makes possible to collect the normal component of the field above the circuit under test. The obtained EM images made possible to evaluate the effect of the wire bonding and their importances for the coplanar structures operating

Styles APA, Harvard, Vancouver, ISO, etc.

34

LESTRINGUEZ, STEPHANE. "Diagnostic electromagnetique d'objets rayonnants complexes, a revetements non parfaitement conducteurs, par une technique de mesure en champ proche." Paris 11, 1998. http://www.theses.fr/1998PA112413.

Texte intégral

Résumé :

L'objectif de ce travail de these est de developper une procedure permettant de diagnostiquer les voies d'entree de l'energie micro-onde a la surface de structures pouvant posseder des zones non parfaitement conductrices (materiaux composites, ouvertures libres). L'approche consiste en une transformation champ proche / champ tres proche, en utilisant comme donnees intermediaires, les courants electriques et magnetiques equivalents circulant a la surface de l'objet sous test. La structure d'etude est consideree comme une antenne en regime d'emission, dont on mesure le champ rayonne en zone proche sur une surface spherique enveloppante. Les courants recherches sont relies a ce champ proche par une relation integrale lineaire, que l'on discretise par la methode des moments. Pour reconstruire les courants surfaciques, il s'agit d'inverser la relation matricielle obtenue. On est alors en presence d'un probleme inverse en electromagnetisme, tridimensionnel, vectoriel, qui a la particularite d'etre mal pose. Des techniques de regularisation doivent par consequent etre appliquees pour obtenir une solution stable. La methode choisie est la methode de type tikhonov, associee a la methode de validation croisee generalisee pour l'obtention du parametre de regularisation. Une fois les courants connus, le champ peut etre calcule en n'importe quel point de l'espace et, en particulier, en zone tres proche pour le diagnostic. Les materiaux composites a base de fibres de carbone consideres ici s'averent suffisamment conducteurs pour etre traites avec le formalisme de l'efie (sans courants magnetiques). Une premiere phase d'evaluation en probleme direct montre que les courants magnetiques circulant dans les ouvertures libres ont une influence importante sur le champ proche et sur le champ tres proche. L'introduction des courants magnetiques dans le formalisme ainsi que la resolution du probleme inverse associe sont effectuees, dans un premier temps, a partir de donnees simulees a l'aide d'un code de calcul dfdt. La methode mise en place est ensuite appliquee a des donnees experimentales. Les resultats obtenus avec la prise en compte du rayonnement des courants magnetiques attestent des capacites de la procedure de diagnostic a ameliorer la localisation des points de fuite et a augmenter le pouvoir de resolution de l'algorithme.

Styles APA, Harvard, Vancouver, ISO, etc.

35

Jolly, Mohanjit Singh. "A voltage drop study in a megawatt level quasi-steady magnetoplasma dynamic thruster via probe diagnostics." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/46420.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

36

Martinez, Sergio L. "Performance Enhancement In Accuracy and Imaging Time of a Hand-Held Probe-Based Optical Imager." FIU Digital Commons, 2011. http://digitalcommons.fiu.edu/etd/397.

Texte intégral

Résumé :

The Optical Imaging Laboratory has developed a hand-held optical imaging system that is capable of 3D tomographic imaging. However, the imaging system is limited by longer imaging times, and inaccuracy in the positional tracking of the hand-held probe. Hence, the objective is to improve the performance of the imaging system by improving imaging time and positional accuracy. This involves: (i) development of automated single Labview-based software towards near real-time imaging; and (ii) implementation of an alternative positional tracking device (optical) towards improved positional accuracy during imaging. Experimental studies were performed using cubical tissue phantoms (1% Liposyn solution) and 0.45-cc fluorescence target(s) placed under various conditions. The studies demonstrated a 90% reduction in the imaging time (now ~27 sec/image) and also an increase from 94% to 97% in the positional accuracy of the hand-held probe. Performance enhancements in the hand-held optical imaging system have improved its potential towards clinical breast imaging.

Styles APA, Harvard, Vancouver, ISO, etc.

37

Bodén, Ida. "Near infrared and skin impedance spectroscopic in vivo measurements on human skin : development of a diagnostic tool for skin cancer." Doctoral thesis, Umeå universitet, Kirurgi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-50605.

Texte intégral

Résumé :

Every year approximately 2800 Swedes are diagnosed with malignant melanoma, the form of cancer that is most rapidly increasing in incidence in the Western world. The earlier we can identify and diagnose a malignant melanoma, the better is the prognosis. In Sweden, 155 000 benign naevi, harmless skin tumours or moles, are surgically excised each year, many of them because melanoma cannot be dismissed by non-invasive methods. The excisions result in substantial medical costs and cause unrest and suffering of the individual patient. For untrained physicians, it is often difficult to make an accurate diagnosis of melanoma, thus a tool that could help to strengthen the diagnosis of suspected melanomas would be highly valuable. This thesis describes the development and assessment of a non-invasive method for early skin cancer detection. Using near infrared (NIR) and skin impedance spectroscopy, healthy and diseased skin of various subjects was examined to develop a new instrument for detecting malignant melanoma. Due to the complex nature of skin and the numerous variables involved, the spectroscopic data were analysed multivariately using Principal Component Analysis (PCA) and partial leas square discriminant analysis (PLS-DA). The reproducibility of the measurements was determined by calculating Scatter Values (SVs), and the significance of separations between overlapping groups in score plots was determined by calculating intra-model distances. The studies indicate that combining skin impedance and NIR spectroscopy measurements adds value, therefore a new probe-head for simultaneous NIR and skin impedance measurements was introduced. Using both spectroscopic techniques it was possible to separate healthy skin at one body location from healthy skin at another location due to the differences in skin characteristics at various body locations. In addition, statistically significant differences between overlapping groups of both age and gender in score plots were detected. However, the differences in skin characteristics at different body locations had stronger effects on the measurements than both age and gender. Intake of coffee and alcohol prior to measurement did not significantly influence the outcome data. Measurements on dysplastic naevi were significantly separated in a score plot and the influence of diseased skin was stronger than that of body location. This was confirmed in a study where measurements were performed on 12 malignant melanomas, 19 dysplastic naevi and 19 benign naevi. The malignant melanomas were significantly separated from both dysplastic naevi and benign naevi. Overall, the presented findings show that the instrument we have developed provides fast, reproducible measurements, capable of distinguishing malignant melanoma from dysplastic naevi and benign naevi non-invasively with 83% sensitivity and 95% specificity. Thus, the results are highly promising and the instrument appears to have high potential diagnostic utility.

Styles APA, Harvard, Vancouver, ISO, etc.

38

Scharlemann, Carsten A. "Investigation of thrust mechanisms in a water fed pulsed plasma thruster." The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1070354149.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

39

Gilmour, Letitia Hayley. "Probing a redox switch to save lives : development of a bioassay for angiotensinogen to identify women prone to pre-eclampsia." Thesis, University of Canterbury. School of Biological Sciences, 2014. http://hdl.handle.net/10092/9925.

Texte intégral

Résumé :

Angiotensinogen is a blood protein that plays a critical role in the regulation of blood pressure in the body. This protein exists in two forms, oxidised and reduced, determined by the presence or absence of a disulfide bridge between Cys 18 and Cys 138. The ratio of oxidised to reduced angiotensinogen is 60:40 in the blood of healthy individuals - an equilibrium that is disrupted in women who develop pre-eclampsia, leading to a higher proportion of oxidised angiotensinogen in the blood. Pre-eclampsia, one of the leading causes of premature births, is a severe and potentially fatal pregnancy condition characterised by the sudden onset of symptoms such as high blood pressure and proteinuria typically during the third trimester. This condition is responsible for an estimated 550,000 deaths globally each year, and with no available treatment or cure other than early delivery of the child, there is a desperate need for a reliable and predictive diagnostic test for this condition. Can we use angiotensinogen as a biomarker for the early diagnosis of pre-eclampsia? Being able to distinguish between reduced and oxidised angiotensinogen and determine the relative amounts of each in blood samples would be of a huge diagnostic value for this condition. This thesis outlines the expression and purification of recombinant human angiotensinogen in Escherichia coli, and the development of an antibody-based SPR assay for angiotensinogen that was subsequently used to probe whether reduced and oxidised angiotensinogen can be distinguished experimentally. The assay developed was sensitive and reproducible, and demonstrated that the reduced and oxidised forms can be distinguished experimentally. The antibody bound the two forms with differential affinity, due to differences in both the association and dissociation rates of the two forms with the monoclonal antibody. Finally, in an attempt to further elucidate the differences between the two redox states of angiotensinogen, molecular dynamic simulations were carried out on angiotensinogen in the presence or absence of the disulfide bond between Cys 18 and Cys 138. These simulations revealed some quite striking differences in the dynamics between the two forms. Reduced angiotensinogen was found to be more dynamic in regions critical for binding to renin, providing a possible explanation for the reported differential affinity that renin displays for the two forms.1 Thus, reduced and oxidised angiotensinogen show some quite distinct differences and can be distinguished in an SPR-based assay, highlighting their potential for use as a biomarker in a diagnostic bioassay.

Styles APA, Harvard, Vancouver, ISO, etc.

40

Mohale, Mamello. "An electrospun nanofiber colorimetric probe for detection of Alkaline Phosphatase for diagnosis of liver toxicity." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/54532.

Texte intégral

Résumé :

A novel electrospun nanofiber colorimetric probe for the detection of Alkaline Phosphatase (ALP) for diagnosis of liver toxicity was developed through electrospinning of a para nitrophenyl phosphate (pNPP) functionalised nylon polymer. The chemical stability of the enzyme substrate (pNPP) and its two products (para nitrophenol (pNP) and para nitrophenolate (pNPL)) was evaluated in biological (pH 7.4), acidic (pH 2) and alkaline (pH 9) pH, respectively. Enzyme kinetics models of Michaelis Menten (MM) and Lineweaver Burk (LB) were used to characterise free ALP. Solution and nanofiber assaying of free ALP and 10x diluted serum (spiked with ALP) was also carried out. The results demonstrated that pNPP and pNP were colourless while pNPL was yellow which indicated that all reagents were chemically stable. In addition, the chromophore of pNPL exhibited a strong molar extinction coefficient (ε) of 18,458 M-1 cm-1. LB plot being the most accurate compared to MM showed Vmax, Km and excess substrate concentration of 5.5 × 10-3 μmol/min-1, 0.025 mM and 0.25 mM respectively. Solution and nanofiber assaying of free ALP and serum confirmed a direct proportional correlation between the pNPL yellow colour intensity and enzyme activity up to 858 IU/L and 820 IU/L respectively. The dipping of the nanofiber layer into solution showed that the leaching rate of pNPP was extremely high at 1.37 × 10-3 A/min-1 as was observed after only the first 0.25 min interval. However, this was not of great concern since it was also observed that administration of the sample (20 μL) by a dropwise method minimised leaching compared to dipping. The preliminary findings on the effect of temperature on the chemical stability of pNPP indicated that it was stable below temperatures of 40°C while it hydrolysed at 80°C. Therefore a sensitive, rapid and simple colorimetric probe for the detection of ALP was developed. The probe exhibited characteristics that make it suitable to be incorporated into point of care colorimetric liver toxicity diagnostic devices for applications in resource poor settings and telemedicine.

Styles APA, Harvard, Vancouver, ISO, etc.

41

Schafer, Julia A. "High-resolution nonlinear multi-photon laser spectroscopy as a diagnostic probe for isotopes and molecules in biophysical and geochemical applications /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2004. http://wwwlib.umi.com/cr/ucsd/fullcit?p3144305.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

42

Pernová, Jana. "Stavební průzkum a diagnostika konstrukce." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-392306.

Texte intégral

Résumé :

The object of the theoretical part of this diploma thesis is overview of the historical development of reinforced concrete and concrete reinforcements, including the elaboration of a detailed methodology for the assessment of the state of bridge structures. It is applied in practical parts of two bridges independent on each other. There are used the most modern technologies like device Hilti PS1000, profometer PM-630 to diagnose objects and they are completed by chopped probe. It also includes a structural analysis of the load capacity, that concurrently evaluates the quality of the construction.

Styles APA, Harvard, Vancouver, ISO, etc.

43

Li, Ran. "Chemometrics Development using Multivariate Statistics and Vibrational Spectroscopy and its Application to Cancer Diagnosis." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1449067634.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

44

Schoombie, Johannes Loubser. "Genetic engineering of recombinant anti-mycolic acid antibody fragments for use in tuberculosis diagnostics." Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/23688.

Texte intégral

Résumé :

Mycolic acids are long chain lipids from the cell walls of Mycobacterium tuberculosis. The Nkuku phage display library was previously used to obtain monoclonal antibody binders to mycolic acids. In total 11 binders were obtained of which one was selected (MAC10) for further investigation by genetic engineering as presented in this dissertation. The antibodies of the Nkuku phage display library are in the format of single chain variable fragments (scFv). ScFv’s constitute only the epitope binding domains of an antibody consisting of the VH and VL domains fused into a single chain by a flexible linker protein. The selected anti-mycolic acid scFv is referred to as mycolic acid clone 10 (MAC10). Genes encoding the scFv’s of the Nkuku phage display library were cloned into the plasmid pHEN-1, a phage display vector. This vector is not commercially available or ideally suited for expression of scFv proteins. Therefore two vectors were investigated as possible targets for subcloning. The plasmids pGE20 and pAK400 were previously used for the expression of scFv antibody proteins. Subcloning into plasmid pAK400 proved to be the more efficient of the two investigated for subcloning. This subcloning yielded the recombinant plasmid pAKJS. Following the subcloning scFv protein expression was attempted using the plasmids pMAC10 (derived from pHEN-1) and pAKJS (derived from pAK400). Expression of MAC10 using plasmid pMAC10 in both Escherichia coli TG-1 and HB2151 was constitutive. This demonstrates that plasmid pHEN-1 is a non ideal vector as expression should not occur unless induced. Expression of MAC10 did not occur when pAKJS and Escherichia coli HB2151 were used. This was due to both the vector and expression host producing inhibitor protein for the Lac Z promoter controlling expression of the scFv. The MAC10 gene was subsequently randomized using the directed evolution method, error prone PCR. Sequence analysis of the five selected mutants indicated an average mutation rate of 8.6 mutations per 1000 base pairs. From the combined total of all five mutants, transversions made up the majority of substitutions. The majority of transversion mutations occurred at A-T base pairs. Transition substation mutations that made up the minority of total mutations occurred mostly at G-C base pairs. Dissertation (MSc)--University of Pretoria, 2012. Biochemistry unrestricted

Styles APA, Harvard, Vancouver, ISO, etc.

45

Danko, Marianna. "Perception et vécu subjectif de stigmatisation familiale chez le proche aidant d’une personne ayant reçu le diagnostic de maladie d’Alzheimer (MA)." Thesis, Montpellier 3, 2016. http://www.theses.fr/2016MON30045/document.

Texte intégral

Résumé :

L'objectif de cette thèse est d'explorer la stigmatisation perçue liée à la maladie d'Alzheimer (MA) parmi une population d'aidants familiaux (enfants adultes ou conjoints) accompagnant leurs proches (conjoints ou parents) vivant avec une probable MA. Parmi les patients, non seulement, il est examiné les sources de stigmatisation envers les personnes vivant avec une probable MA associées aux réactions émotionnelles et comportementales d'affiliation ou de distance sociale de l'entourage. Mais encore il est observé les facteurs de stigmatisation qui prédisent une variation de leur qualité de vie. Parmi, leurs aidants familiaux, il est étudié les facteurs de stigmatisation qui prédisent une variation de la symptomatologie dépressive et du fardeau de soins. Dans cette relation, il est étudié le rôle modérateur du soutien social. Nos résultats indiquent parmi les patients, que la fréquence des symptômes comportementaux liés à la dépression prédisent les émotions négatives et les comportements de distance sociale de l'entourage. Aussi, nous observons que la qualité de vie du patient varie selon son lieu de résidence. Au domicile, il est observé davantage de comportements de distance sociale venant de l'entourage. Parmi les proches aidants, il est constaté que soutien social modère les effets entre les émotions négatives, les comportements de distance sociale de l'entourage envers le patient, et la symptomatologie, le fardeau de soins des aidants. Mais que le soutien social exacerbe les effets entre les émotions positives de l'entourage et le fardeau de soins. Cette thèse permet d'objectiver la stigmatisation liée à la maladie d'Alzheimer parmi les patients et leurs proches aidants. Les résultats obtenus justifieraient l'élaboration d'actions de communication centrées sur la nécessité du soutien social auprès de l'ensemble des personnes affectées par la maladie d'Alzheimer This thesis aims at exploring the perceived stigmatization towards persons possibly leaving with Alzheimer’s disease among the population of the family caregivers – grown-up children and spouses. Not only do we have observed sources of stigmatizations aimed at patients possibly leaving with Alzheimer’s disease, in relation with emotional reactions and either affiliation behavior, or social distancing from the family and social circle, but we have also observed factors of stigmatization leading to variations in patients’ quality of life. Amongst family caregivers, we have studied factors of stigmatization leading to changes in the associated depressive symptoms and the increased caregiver burden. With respect to the relationship induced, we have given attention to the moderating role of social support. Our results show that, among patients, the negative emotions and the social distancing behavior from social circle can be linked to the frequency of behavioral symptoms related to the depression. With respect to this observation, we show an variation in the patients’ quality of life according to the places they live in. At home, we have noted increased social distancing behavior from the social circle. Amongst the relatives caregivers, we have also noticed that social support has a moderating influence on the effects of negative emotions, the social distancing behavior from the social circle towards the patient, the symptoms and the burden of care felt by the caregivers. However, the social support exacerbates the relation between positive emotions among the relatives and the burden of care. This thesis gives us the opportunity to objectify the stigmatization process with respect to Alzheimer’s disease amongst patients and their relatives caregivers. Our results could open the way to specific communications promoting the necessity for social support in favor of the entire population concerned by Alzheimer’s disease

Styles APA, Harvard, Vancouver, ISO, etc.

46

Mengoli, Serena. "Diagnostica delle murature storiche: studio del quadro fessurativo, prove soniche e tomografia nell'ex chiesa di San Barbaziano in Bologna." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amslaurea.unibo.it/373/.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

47

Sio, Hong (Hong Weng). "Using time-resolved nuclear diagnostics to probe kinetic/multi-ion physics and shock dynamics on OMEGA and the NIF." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/119926.

Texte intégral

Résumé :

Thesis: Ph. D., Massachusetts Institute of Technology, Department of Physics, 2018. Cataloged from PDF version of thesis. Includes bibliographical references (pages 263-261). This thesis focuses on the development and application of time-resolved nuclear diagnostics to probe plasma evolution in Inertial Confinement Fusion (ICF) implosions. On the OMEGA laser facility at the Laboratory for Laser Energetics (LLE) in Rochester, New York, the impact of kinetic and multi-ion effects on ICF implosion performance is studied using the Particle X-ray Temporal Diagnostic (PXTD). PXTD is a versatile streaked instrument for measurements of multiple X-ray-emission and nuclear-reaction histories with high relative timing precision, and developed to probe the time evolution of plasma conditions during the shock phase of ICF implosions. Assessing the roles kinetic and multi-ion effects play in ICF implosions is especially important because ICF implosion simulations heavily rely on radiation-hydrodynamic codes that do not model these effects. However, most experimental results thus far made use of only time-integrated observables. Using PXTD, time-resolved observations of fuel-ion species dynamics in ICF implosions have been made using multiple nuclear reaction histories. These time-resolved measurements have also been extended to infer ion and electron temperature histories in ICF implosions. On the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL), implosion dynamics from shock to compression are probed using the magnetic particle time-of-flight (magPTOF) diagnostic. magPTOF is designed to simultaneously measure the shock and compression timings in D 3 He-gas-filled implosions on the NIF. In combination with other nuclear and X-ray diagnostics, magPTOF is used to assess areal density, areal density asymmetry, implosion velocity, and mix. by Hong Sio. Ph. D.

Styles APA, Harvard, Vancouver, ISO, etc.

48

Řezáčová, Veronika. "Diagnostický průzkum objektu historické budovy." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225662.

Texte intégral

Résumé :

This thesis deals with the methodology, implementation and evaluation of diagnostic work units and structural elements of the historic schoolhouse building. Includes a static assessment of the horizontal structure and conceptual design layout adjustments for potential revitalization in case the object.

Styles APA, Harvard, Vancouver, ISO, etc.

49

Bore, Thierry. "Amélioration du diagnostic de l'endommagement des gaines de précontrainte extérieure par sonde capacitive." Phd thesis, Conservatoire national des arts et metiers - CNAM, 2011. http://tel.archives-ouvertes.fr/tel-00592267.

Texte intégral

Résumé :

Les travaux présentés dans cette thèse contribuent au développement du contrôle non destructif des conduits de précontrainte extérieure dans les ouvrages d'art. Une sonde capacitive a été développée pour ausculter ces conduits. L'objectif est d'en améliorer le diagnostic.Dans un premier temps, une cellule de mesure en transmission coaxiale a été développée pour caractériser les matériaux présents dans le conduit sur la bande de fréquence 50 MHz - 1 GHz. Le ciment, les produits de la ségrégation du ciment et la cire d'injection ont été étudiés.La deuxième partie du travail exploite ces résultats dans une modélisation directe du problème global. Une étude paramétrique nous a permis de proposer une méthode d'estimation de l'épaisseur de vide à l'intérieur du conduit à partir des signaux délivrés par la sonde, qui a pu être validée sur une maquette de conduit. A partir de ces résultats sont proposées plusieurs améliorations du dispositif visant à l'obtention de signaux plus riches issus des capteurs, afin de pouvoir estimer un plus grand nombre de paramètres.

Styles APA, Harvard, Vancouver, ISO, etc.

50

Courrier, Emilie. "Biomarqueurs fluorescents, marqueurs et instruments optiques dédiés pour le diagnostic in vivo des pathologies cornéennes." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSES029.

Texte intégral

Résumé :

Un déséquilibre dans les mécanismes de défense de la cornée peut entraîner une invasion par des micro-organismes (MO) et générer une kératite infectieuse (KI), ou encore un syndrome sec. Les KI sont la première cause de cécité monoculaire. Le syndrome sec, également fréquent, est sujet à de nombreuses études cliniques pour l’évaluation de nouveaux traitements. L’objectif de cette thèse est de mettre au point des méthodes d’imagerie pour le diagnostic et le suivi des pathologies de la surface oculaire au travers de deux projets innovants : 1/ le projet FLUOCOR consistant à développer une solution complète de diagnostic rapide in vivo des MO les plus souvent responsables des KI afin de débuter immédiatement le traitement adapté et améliorer le pronostic visuel final. Cette solution comprendra des BioMarqueurs fluorescents (BMfs) spécifiques des agents infectieux, fluorescents dans le rouge ou le proche infrarouge non éblouissant et un nouvel instrument optique de détection. Des BMfs basés sur le couplage de BODIPY innovant avec des molécules ciblant les MO ont été obtenus. Des tests in vitro ont montré une bonne spécificité mais les tests ex vivo sur cornées humaines ont montré une fixation non spécifique sur les cellules épithéliales. Pour pallier ce manque de spécificité, le couplage de ces BODIPY sur des anticorps dirigés contre les MO est en cours. 2/ le projet FLUOSCOPE qui a permis de développer une nouvelle stratégie d’imagerie de la surface oculaire pour le suivi du syndrome sec, de la méthode d’instillation des colorants jusqu’au traitement d’images, en passant par la conception d’un instrument optique désormais industrialisé par les laboratoires Théa An imbalance in the defence system of cornea can result in several diseases, like infectious keratitis (IK) in case of invasion by microorganisms (MO) or dry eye in case of insufficient tear quality and/or quality. IK are the first cause of unilateral blindness worldwide. Sicca syndrome, also frequent, is the subject of numerous clinical trials assessing new treatments. The aim of the PhD Thesis work is to develop new imaging methods for the diagnosis and follow-up of diseases of the ocular surface. Two innovative project were conducted: 1/ the FLUOCOR project consists in developing a complete solution of rapid in vivo etiologic diagnosis of IK, for the most frequent and/or severe infections to allow rapid starting of the most adapted treatment in order to improve the final visual prognosis. This solution will comprise fluorescent biomarkers (excitable by sustainable non blinding red or near infrared lights) specific to the target MO, and a new optical imaging device for their detection. Biomarkers based on new BODIPY coupled with molecules targeting the MO were obtained with a good in vitro specificity. Nevertheless, on ex vivo human corneas they stained superficial epithelial cells. In order to overcome this difficulty, the coupling of BODIPY on specific antibodies targeting the MO is ongoing; 2/ the FLUOSCOPE project that allowed development of a new strategy of ocular surface imaging for the diagnosis and follow up of sicca syndrome. The complete chain was revisited from the instillation of the dye to the objective quantification of staining by image analysis, through the development of a prototype of imaging device, now industrialized by les Laboratoires Thea

Styles APA, Harvard, Vancouver, ISO, etc.

Thèses sur le sujet « Diagnostic proce »

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres