Thèses : « 13C detection »

1

Day, S. E. « Detection of tumour treatment response using hyperpolarized 13C pyruvate ». Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598434.

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The exchange reaction between hyperpolarized 1-¹³C pyruvate and lactate, catalysed by the enzyme lactate dehydrogenase (LDH), can now be measured in real-time with ¹³C nuclear magnetic resonance spectroscopy and imaged in tissues using ¹³C MRI. EL-4 murine lymphoma cells catalyse this pyruvate-lactate exchange in a substrate-dependent fashion, and we demonstrate that the reaction is inhibited following treatment with chemotherapeutic drugs both in vitro and in vivo. The LDH reaction specifically labels the intratumoural lactate pool present within solid EL-4 murine lymphoma tumours, and this exchange was reduced following treatment with the chemotherapeutic drug etoposide. This novel metabolic imaging technique can be predictive of therapeutic success. The C6 intracranial rat glioma faithfully reproduces many morphological aspects of the human disease, and can be used as a model for the study of human brain tumours. When hyperpolarized pyruvate was administered to C6 glioma bearing rats, there was specific labelling of intratumoural lactate, and little to no polarized substrate in the normal brain. Following radiation therapy of these glioma bearing rats, the exchange of label between pyruvate and lactate was reduced as measured using chemical-shift imaging and was predictive of therapeutic success. Taken together, these results demonstrate the potential for hyperpolarized ¹³C pyruvate imaging to detect treatment response in vivo in different models of cancer. This work details initial studies into what might be a potentially valuable metabolic imaging tool. Hopefully this tool may one day be used by clinicians to improve the management of human cancer patients.

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Jordaan, Maraliese. « Diagnosis of helicobacter pylori infection with the 13C-urea breath test : analysis by means of gas chromatography with mass selective detection ». Diss., University of Pretoria, 2007. http://hdl.handle.net/2263/27035.

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3

Gnanapandithan, Nithya. « Data detection and fusion in decentralized sensor networks ». Thesis, Manhattan, Kan. : Kansas State University, 2005. http://hdl.handle.net/2097/132.

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4

Li, Zizheng. « Vertical Noise Structure and Target Detection Performance in Deep Ocean Environments ». PDXScholar, 2010. https://pdxscholar.library.pdx.edu/open_access_etds/138.

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In passive sonar systems, knowledge of low-frequency shipping noise is an important factor for target detection performance. However, an accurate model for the shipping noise structure is difficult to obtain, due to the varying distributions of ships and complicated underwater environment. This work characterizes low-frequency distant shipping noise observed in deep water environments as a function of receiver depth and vertical arrival structure for the case of a receiver below the conjugate depth. Surface shipping noise is examined using Monte Carlo simulations using a normal mode propagation model based on random distribution of ships and realistic parameters. The depth dependence of the simulated distant shipping noise is in agreement with published experimental measurements. A Vertical Line Array (VLA) is used to produce vertical beams that isolate the surface interference from nearby targets. Simulation results quantifying the beamformer output as a function of ocean environment, receiver aperture, and frequency are presented for both conventional and adaptive beamformers. The results suggest that conventional beamforming could detect the noisy target from both direct arrival and bottom bounce in the presence of distant shipping interferers and wind noise. However, the beamwidth of conventional beamforming is wider than that of adaptive beamforming. Once the motion effects of nearby ship interferences are considered, the adaptive beamforming using diagonal loading provides better detection performance. Preliminary adaptive beamforming results corresponding to different snapshot times show that motion effects can be minimized by using short observation times.

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Demir, Sumeyra Ummuhan. « Image Processing Algorithms for Diagnostic Analysis of Microcirculation ». VCU Scholars Compass, 2010. http://scholarscompass.vcu.edu/etd/137.

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Microcirculation has become a key factor for the study and assessment of tissue perfusion and oxygenation. Detection and assessment of the microvasculature using videomicroscopy from the oral mucosa provides a metric on the density of blood vessels in each single frame. Information pertaining to the density of these microvessels within a field of view can be used to quantitatively monitor and assess the changes occurring in tissue oxygenation and perfusion over time. Automated analysis of this information can be used for real-time diagnostic and therapeutic planning of a number of clinical applications including resuscitation. The objective of this study is to design an automated image processing system to segment microvessels, estimate the density of blood vessels in video recordings, and identify the distribution of blood flow. The proposed algorithm consists of two main stages: video processing and image segmentation. The first step of video processing is stabilization. In the video stabilization step, block matching is applied to the video frames. Similarity is measured by cross-correlation coefficients. The main technique used in the segmentation step is multi-thresholding and pixel verification based on calculated geometric and contrast parameters. Segmentation results and differences of video frames are then used to identify the capillaries with blood flow. After categorizing blood vessels as active or passive, according to the amount of blood flow, quantitative measures identifying microcirculation are calculated. The algorithm is applied to the videos obtained using Microscan Side-stream Dark Field (SDF) imaging technique captured from healthy and critically ill humans/animals. Segmentation results were compared and validated using a blind detailed inspection by experts who used a commercial semi-automated image analysis software program, AVA (Automated Vascular Analysis). The algorithm was found to extract approximately 97% of functionally active capillaries and blood vessels in every frame. The aim of this study is to eliminate the human interaction, increase accuracy and reduce the computation time. The proposed method is an entirely automated process that can perform stabilization, pre-processing, segmentation, and microvessel identification without human intervention. The method may allow for assessment of microcirculatory abnormalities occurring in critically ill and injured patients including close to real-time determination of the adequacy of resuscitation.

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Murino, Loredana. « Discovering hidden structures in high ». Doctoral thesis, Universita degli studi di Salerno, 2011. http://hdl.handle.net/10556/137.

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2009 - 2010
Il grande volume di dati che viene attualmente collezionato nei vari campi di applicazione non può essere gestito usando le tecniche standard di data mining. L’obiettivo principale del presente lavoro di tesi è quello di trovare le soluzioni più ragionevoli per problemi di data mining legati alla gestione di dati ad alta dimensionalità. In particolare in questo lavoro di tesi sono stati considerate due applicazioni di data mining per dati multidimensionali. Il primo riguarda la cloud detection, ovvero un problema di classificazione di immagini multispettrali telerilevate da satellite, che dimostra l’alta affidabilità delle tecniche statistiche di analisi discriminante nel classificare questo tipo di immagini. Tali tecniche di classificazione sono state confrontate con tecniche standard basate su principi fisici per testare i costi di processo e il tasso pass/fail. La seconda applicazione riguarda la necessità di gestire dati multidimensionali per i quali è necessario fare assunzioni piuttosto che avere conferme (come nella precedente applicazione). Questo porta in modo naturale al problema del clustering di dati permettendo di trovare strutture significative all’interno degli stessi. Invece di scegliere l’una o l’altra tecnica di clustering, noi abbiamo scelto di approcciare il problema in modo più generale mediante il cosiddetto “consensus clustering”: piuttosto che cercare una singola soluzione al problema, l’obiettivo è trovare tutte le possibili soluzioni equivalentemente valide. A questo scopo è stata sviluppata una procedura automatica basata sul Least Squares Consensus Clustering. Le applicazioni sono state testate usando sia data-sets sintetici che reali,dimostrando la validità delle procedure. Grande enfasi è stata data anche alla validazione dei risultati attraverso l’uso di indicatori di performance per dimostrare l’affidabilità delle tecniche sviluppate. [edited by author]
IX n.s.

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Corcoran, Elaine M. « The trace detection of DNA adducts by accelerator mass spectrometry and 14C-postlabelling ». Thesis, University of Leicester, 2004. http://hdl.handle.net/2381/30774.

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Accelerator mass spectrometry (AMS) is currently the most sensitive method for trace DNA adduct detection. O6-Mehtyldeoxyguanosine (O 6-MedG) is a strongly mutagenic lesion formed by a variety of alkylating agents. For this reason this was the adduct of choice for use in this study, the aim of which was to develop a 14C-postlabelling technique, involving incorporation of radiolabel onto O6-MedG adducts after isolation, thus enabling exploitation of AMS to detect low levels of adducts without the need to administer a 14C-labelled compound. A method was developed and optimised for acetylating O6-MedG, in < 90% yields. This method was then used to acetylate the adduct with 14C-acetic anhydride, but changes required for the safe handling of radiolabelled compound altered the reaction product profile, resulting in the major derivative being 14C-di-acetyl O6-MedG, (38% yield). This pure standard was used to determine detection limits of 1.4 pmoles of adduct using HPLC and liquid scintillation counting and 79 attomoles using AMS. A 3H-O6MedG standard was used to determine the efficiency of each stage of the 14C-postlabelling procedure. Overall assay efficiency was calculated to be 29% and taking this into account the practical limit of detection for the 14C-postlabelling procedure was calculated to be 272 attomoles of adduct. The assay was then utilised to quantitate O6-MedG adducts formed by exposure of DNA with MNU. The theoretical limit of detection was 3 adducts/1012 nucleosides, based on background 14C levels in blank HPLC fractions, which indicates the assay should ultimately be the most sensitive for detection of endogenous O6-MedG adducts in control human DNA. The techniques developed for this assay were utilised to quantitate O6-MedG adducts formed in DNA exposed to 14C-S-adenosylmethionine. Unfortunately no adducts were conclusively detected by AMS due to contamination of the samples, highlighting the problem of contamination in AMS analysis. However, with the addition of further purification steps, this assay could be sensitive enough to detect O6-MedG formed by the suspected endogenous carcinogen.

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Asami, Sam. « Method development for biomolecular solid-state NMR spectroscopy ». Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2014. http://dx.doi.org/10.18452/17044.

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Im Rahmen der vorliegenden Arbeit, wird ein neuartiges Markierungsschema für die Festkörper-NMR-Spektroskopie vorgestellt, das sogenannte Reduced Adjoining Protonation (RAP) Schema, welches die Protonendetektion sämtlicher Aliphaten erlaubt. Hochaufgelöste, 1H-detektierte 1H,13C Korrelationsspektren wurden erhalten. Des Weiteren wurde der Vorteil von hohen MAS-Frequenzen untersucht. 1H- und 13C-detektierte 3D Zuordnungsexperimente wurden implementiert, welche uns die Zuordnung von 90% aller aliphatischen Resonanzen von alpha-Spektrin SH3 erlaubten. Da die chemische Verschiebung abhängt vom Strukturmotiv, kann sie verwendet werden, um Sekundärstruktur-Informationen abzuleiten. Darüber hinaus wurde ein 1H-detektiertes H(H)CH 3D Experiment entwickelt, um weitreichende 1H,1H Kontakte zu ermitteln, welche für die Bestimmung der Tertiärstruktur genutzt werden können. Um artefaktfreie Relaxationsdaten zu erhalten, wurde das RAP-Markierungsschema modifiziert, um 1H- und 13C-verdünnte Proben zu erhalten, in denen Spindiffusion unterdrückt ist. Für die Untersuchung von Sub-Mikrosekunden-Dynamik werden Experimente vorgestellt zur Bestimmung von 13C T1 Relaxationszeiten und 1H,13C dipolaren Kopplungstensoren für Rückgrat- und Seitenketten-Resonanzen. Des weiteren zeigen wir, dass das RAP-Markierungsschema auf nicht-kristalline Systeme, wie Amyloidfibrillen des Abeta1-40 Peptids der Alzheimer-Krankheit, angewendet werden kann. Unter Verwendung von 1H-Detektion, erhielten wir hochaufgelöste 1H,13C Korrelationsspektren. Schließlich wurde der Perdeuterierungsansatz auf den L7Ae-box C/D Protein-RNA Komplex aus P. furiosus angewendet. Wir erhielten hochaufgelöste, 1H-detektierte 1H,15N, sowie 13C,13C Korrelationsspektren des Protein-RNA Komplexes. Weiterhin haben wir eine Methode zur Bestimmung genauer Abstands- und Winkelinformationen für die Protein-RNA Schnittstelle etabliert und schlagen Ansätze vor, für die Zuordnung der chemischen Verschiebungen von RNA-Resonanzen.
In this thesis, a novel labeling scheme for solid-state NMR spectroscopy, the Reduced Adjoining Protonation (RAP) scheme, is introduced, which allows proton detection of all aliphatic sites, as shown for the microcrystalline SH3 domain of alpha-spectrin. These samples yield high-resolution, 1H-detected 1H,13C correlation spectra. In addition, the benefit of high MAS frequencies was investigated. 1H- and 13C-detected 3D assignment experiments are implemented, which allowed us to assign 90% of all aliphatic resonances of alpha-spectrin SH3. As the chemical shift is dependent on the structural motif, it can be employed to derive secondary structure information. Furthermore, a 1H-detected H(H)CH 3D experiment is introduced, to obtain long-range 1H,1H contacts, which can be used for the determination of the tertiary structure. To obtain artifact-free relaxation data, the RAP labeling scheme was modified to obtain sparsely proton labeled, 13C dilute samples, in which spin diffusion is suppressed. To probe sub-microsecond dynamics, we report experiments to determine 13C T1 relaxation times and 1H,13C dipolar coupling tensors for backbone and side chain resonances, respectively. Furthermore, we show, that the RAP labeling scheme can be applied to non-crystalline systems, such as amyloid fibrils of the Alzheimer’s disease peptide Abeta1-40. Using 1H-detection, we obtained high-resolution 1H,13C correlation spectra. Finally, we applied the perdeuteration approach to the L7Ae-box C/D protein-RNA complex from P. furiosus. We obtained high-resolution, 1H-detected 1H,15N, as well as 13C,13C correlation spectra of the protein-RNA complex. In addition, we established a methodology to determine accurate distance and angular restraints for the protein-RNA interface and propose approaches for the chemical shift assignment of RNA resonances.

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Martel, Christopher. « Development of a Mass Detection Technique to Detect Intakes of Radioactive Material and their Resulting Radiation Exposures Following a Large-Scale Radiological Release ». Digital WPI, 2019. https://digitalcommons.wpi.edu/etd-dissertations/520.

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Large-scale radiological accidents have resulted in intakes of radioactive materials by members of the public and occupational radiation workers. However, current methods to evaluate intakes are designed for small numbers of individuals and cannot be easily scaled for large populations as has occurred. A proposed method for high throughput volumes of people to identify and quantify intakes of radioactive material through urine radiobioassay is described. MATERIALS AND METHODS: The MCNP V6.0 software code was used to model the General Electric Hawkeye V3 Gamma Camera for gamma ray efficiency. Technitium-99m was used to validate the model. The model was used to calculate detection efficiencies and minimum detectable doses for Cobalt-60, Iodine-131, Cesium-137/Barium-137m and Iridium-192. RESULTS: Differences of 8% were observed between measurements of the detection efficiency for Technitium-99m and the MCNP modeled detection efficiency (11.1% vs. 12.0%, respectively). Calculations showed that a dose of 20 mSv could be detected using urine radiobioassay in 6, 3, 2, and 20 days post incident for Type F intakes of Cobalt-60, Iodine-131, Cesium-137/Barium-137m and Iridium-192 respectively. Approximately 1,152 urine samples could be analyzed in an eight-hour shift using a single gamma camera. CONCLUSIONS: The use of the gamma camera for urine radiobioassay allows for high throughput volumes of samples and has sufficient detection sensitivity to meet dose-based decision guidelines.

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LI, Haibing. « Financial fraud detection by using grammar-based multiobjective genetic programming with ensemble learning ». Digital Commons @ Lingnan University, 2015. https://commons.ln.edu.hk/cds_etd/13.

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Financial fraud is a criminal act, which violates the law, rules or policy to gain unauthorized financial benefit. As an increasingly serious problem, it has attracted a lot of concerns. The major consequences are loss of billions of dollars each year, investor confidence and corporate reputation. Therefore, a study area called Financial Fraud Detection (FFD) is obligatory, in order to prevent the destructive results caused by financial fraud. In general, traditional modeling approaches are applied and based on pre-defined hypothesis testing of causes and effects for FFD problems. In addition, the evaluation criteria are often based on variable significance level or Goodness-of-fit only. FFD has many common features like other data mining problems. It has accumulated vast amounts of data records of different forms (e.g. financial statements or annual reports) over a period of time. It is very difficult to observe the interesting information just by relying on traditional statistical methods. However, data mining techniques can be used to extract implicit, previously unknown and potentially useful patterns, rules or relations from massive data repositories. Such discovered patterns are appropriate to executive leadership, stakeholders and related regulatory agencies to reduce or avoid the losses. As real-life problems, it is not sufficient for FFD to consider only a single criterion (e.g. Goodness-of-fit or accuracy). Instead, FFD can also seek multiple objectives (e.g. accuracy versus interestingness). It is not easy to consider multiple objectives at the same time unless applying combination methods (e.g. linear combination) by assigning different weights to present the importance for each criterion by using data mining techniques with a single evaluation criterion. For example, accuracy is more important than interestingness with weights of 0.9:0.1. But it is still difficult to decide the appropriate or exact values for weights. There-fore, multi-objective data-mining techniques are required to tackle FFD problems. In this study, FFD is targeted, and comprehensively evaluated by a number of methods. The proposed method is based on Grammar-Based Genetic Programming (GBGP), which has been proven to be a powerful data mining technique to generate compact and straightforward results. The major contributions are three improvements of GBGP for FFD problems. First, multi-criteria are considered by integrating the concept of multi-objectives into GBGP. Second, minority prediction is applied to demonstrate the class prediction with unmatched rows in their rules. Lastly, a new meta-heuristic approach is introduced for ensemble learning in order to help users to select patterns from a pool of models to facilitate final decision-making. The experimental results showed the effectiveness of the new approach in four FFD problems including two real-life problems. The major implications and significances of the study can concretely generalize for three points. First, it suggests a new ensemble learning technique with GBGP. Second, it demonstrates the usability of classification rules generated by the proposed method. Third, it provides an efficient multi-objective method for solving FFD problems.

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Para, Prashanthi. « FABRICATION OF NANOSTRUCTURES FOR IMPROVED PERFORMANCE OF ELECTROCHEMICAL SENSORS AND FOR REFERENCE COMPENSATION IN LOCALIZED SURFACE PLASMON RESONANCE SENSORS ». UKnowledge, 2009. http://uknowledge.uky.edu/gradschool_theses/130.

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L‐glutamate is associated with several neurological disorders; thus, monitoring fast dynamics of L‐glutamate is of great importance in the field of neuroscience. Electrode miniaturization demanded by many applications leads to reduced surface area and decreased amounts of immobilized enzymes on coated electrodes. As a result, lower signal‐to‐noise ratios are observed for oxidase‐enzyme based sensors. To increase the signal‐to‐noise ratio we have developed a process to fabricate micro‐ and nano‐ structures on the microelectrode surface. Localized surface‐plasmon resonances (SPR) has been extensively used to design label‐free biosensors that can monitor receptor‐ligand interactions. A major challenge with localized SPR sensors is that they remain highly susceptible to interference because they respond to both solution refractive index changes and surface binding of the target analyte. The key concept introduced in the present work is the exploitation of transverse and longitudinal resonance modes of nanorod arrays to differentiate between bulk refractive index changes and surface interactions. The transverse bulk sensitivity of the localized SPR sensor (107 nm/RIU) remains competitive with typical single mode gold nanosphere SPR sensors. The figure of merit for the device’s cross‐sensitivity (1.99) is comparable to that of typical wavelength‐interrogated propagating SPR sensors with self referencing.

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Wegrzyn, Jana. « Practice Makes the Deficiency of Global Motion Detection in People With Pattern-Related Visual Stress More Apparent ». Thesis, NSUWorks, 2019. https://nsuworks.nova.edu/hpd_opt_stuetd/13.

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Pattern-related visual stress (PRVS) refers to the perceptual difficulties experienced by some individuals when exposed to high contrast striped patterns. People with PRVS were reported to have reduced sensitivity to global motion at baseline testing and the difference disappears at a second estimate. The present study was to investigate the effect of practice on global motion threshold in adults with and without PRVS. Methods: A total of 101 subjects were recruited and the Wilkins & Evans Pattern Glare Test was used to determine if a subject had PRVS. The threshold to detect global motion was measured with a random dot kinematogram. Each subject was measured 5 times at the first visit and again a month later. Receiver operating characteristic (ROC) curve analysis was applied to show the agreement between the two tests. Results: Twenty-nine subjects were classified as having PRVS and 72 were classified as normal. At baseline, the threshold to detect global motion was significantly higher in subjects with PRVS (0.832 ± 0.098 vs. 0.618 ± 0.228, p < 0.001). After 5 sessions, the difference between the normal and subjects with PRVS increased (0.767 ± 0.170 vs. 0.291 ± 0.149, p < 0.001). In ROC analysis, the area under the curve (AUC) improved from 0.792 at baseline to 0.964 at the fifth session. After a one-month break, the difference between normal and subjects with PRVS was still significant (0.843 ± 0.169 vs. 0.407 ± 0.216, p < 0.001) and the AUC was 0.875. Conclusion: The ability to detect global motion is impaired in persons with PRVS and the difference increased after additional sessions of practice.

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Hensel, Stephan, Markus Graube et Leon Urbas. « Methodology for Conflict Detection and Resolution in Semantic Revision Control Systems ». Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-211244.

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Revision control mechanisms are a crucial part of information systems to keep track of changes. It is one of the key requirements for industrial application of technologies like Linked Data which provides the possibility to integrate data from different systems and domains in a semantic information space. A corresponding semantic revision control system must have the same functionality as established systems (e.g. Git or Subversion). There is also a need for branching to enable parallel work on the same data or concurrent access to it. This directly introduces the requirement of supporting merges. This paper presents an approach which makes it possible to merge branches and to detect inconsistencies before creating the merged revision. We use a structural analysis of triple differences as the smallest comparison unit between the branches. The differences that are detected can be accumulated to high level changes, which is an essential step towards semantic merging. We implemented our approach as a prototypical extension of therevision control system R43ples to show proof of concept.

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D'Elia, Gianluca <1980&gt. « Fault detection in rotating machines by vibration signal processing techniques ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/952/1/Tesi_Delia_Gianluca.pdf.

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Machines with moving parts give rise to vibrations and consequently noise. The setting up and the status of each machine yield to a peculiar vibration signature. Therefore, a change in the vibration signature, due to a change in the machine state, can be used to detect incipient defects before they become critical. This is the goal of condition monitoring, in which the informations obtained from a machine signature are used in order to detect faults at an early stage. There are a large number of signal processing techniques that can be used in order to extract interesting information from a measured vibration signal. This study seeks to detect rotating machine defects using a range of techniques including synchronous time averaging, Hilbert transform-based demodulation, continuous wavelet transform, Wigner-Ville distribution and spectral correlation density function. The detection and the diagnostic capability of these techniques are discussed and compared on the basis of experimental results concerning gear tooth faults, i.e. fatigue crack at the tooth root and tooth spalls of different sizes, as well as assembly faults in diesel engine. Moreover, the sensitivity to fault severity is assessed by the application of these signal processing techniques to gear tooth faults of different sizes.

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D'Elia, Gianluca <1980&gt. « Fault detection in rotating machines by vibration signal processing techniques ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/952/.

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Machines with moving parts give rise to vibrations and consequently noise. The setting up and the status of each machine yield to a peculiar vibration signature. Therefore, a change in the vibration signature, due to a change in the machine state, can be used to detect incipient defects before they become critical. This is the goal of condition monitoring, in which the informations obtained from a machine signature are used in order to detect faults at an early stage. There are a large number of signal processing techniques that can be used in order to extract interesting information from a measured vibration signal. This study seeks to detect rotating machine defects using a range of techniques including synchronous time averaging, Hilbert transform-based demodulation, continuous wavelet transform, Wigner-Ville distribution and spectral correlation density function. The detection and the diagnostic capability of these techniques are discussed and compared on the basis of experimental results concerning gear tooth faults, i.e. fatigue crack at the tooth root and tooth spalls of different sizes, as well as assembly faults in diesel engine. Moreover, the sensitivity to fault severity is assessed by the application of these signal processing techniques to gear tooth faults of different sizes.

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Nkhebenyane, Jane Sebolelo. « Microbial hazards associated with food preparation in Central South African HIV/Aids hospices ». Thesis, Bloemfontein : Central University of Technology, Free State, 2010. http://hdl.handle.net/11462/135.

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Thesis (M. Tech.) -- Central University of Technology, Free State, 2010
South Africa currently faces one of the highest HIV prevalence rates in the world. As this prevalence rises, the strain placed on its hospitals is likely to increase due to the shortage of beds. The devastating effects of HIV/AIDS initiated the establishment of a hospice which is a non-governmental organisation whose goal is the provision of care for terminally ill patients, either in their homes, in hospitals or in a hospice’s own in-patients wards. Part of the hospice’s mission is to offer palliative care without charge to anyone who requires it. The basic elements of hospice care include pain and symptom management, provision of support to the bereaving family and promoting a peaceful and dignified death. This also includes the provision of cooked foods to the patients using the kitchen facilities of the hospices for this activity. It is well known that the kitchen is particularly important in the spread of infectious disease in the domestic environment due to many activities that occur in this particular setting. Food and water safety is especially important to the persons infected with the human immunodeficiency virus (HIV) or with immunodeficiency syndrome (AIDS).It is estimated that food-borne pathogens (disease–causing agents) are responsible for 76 million illnesses, some resulting in death, in the United States alone every year. In one study of patients with AIDS, two-thirds had diarrhoeal disease and in two-thirds of these, the following enteric pathogens were identified: Salmonella, Shigella, Listeria, Yersnia, Cryptosporidium, Entamoeba histolylica and Campylobacter sp. In an epidemiological study of patients with HIV infection a close association was found between consumption of raw or partially cooked fish and antimicrobial-resistant Mycobacterium avium complex. Antibiotic resistance in food-borne pathogens has become a reality and this poses a serious threat to the medical fraternity since it diminishes the effectiveness of treatment. This study was undertaken to determine the prevalence of foodborne pathogens including bio aerosols isolated from the kitchen surfaces and food handler’s before and after cooking. The antibiotic resistance of the isolated pathogens was further determined to assess their impact on treatment. The following microbiota were isolated: Total viable counts (TVC), Coliforms, Escherichia coli, Staphylococcus aureus, Pseudomonas and presumptive Salmonella. The hospices had high counts of E.coli and S.aureus on the cutting boards for the breakfast session compared to the traditional home based kitchens. It was speculated that this could have originated from crosscontamination via the foodhandler’s hands and the food served. It is evident from the results that hospices lack a management system regarding the prevalence of E. coli as it was present on the cutting boards throughout the food preparation sessions. Gram negative organisms (coliform and P. aeruginosa) were in particular both resistant to oxacillin and this pose a great challenge in this particular setting. This can be addressed by putting emphasis on hygiene as a strategy per se for reducing antibiotic resistance.

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Raut, Nilesh G. « BIOSENSING SYSTEMS FOR THE DETECTION OF BACTERIAL QUORUM SENSING MOLECULES : A TOOL FOR INVESTIGATING BACTERIA-RELATED DISORDERS AND FOOD SPOILAGE PREVENTION ». UKnowledge, 2012. http://uknowledge.uky.edu/chemistry_etds/13.

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Quorum sensing enables bacteria to communicate with bacteria of the same or different species, and to modulate their behavior in a cell-density dependent manner. Communication occurs by means of small quorum sensing signaling molecules (QSMs) whose concentration is proportional to the population size. When a QSM threshold concentration is reached, certain genes are expressed, thus allowing control of several processes, such as, virulence factor production, antibiotic production, and biofilm formation. Not only many pathogenic bacteria are known to produce QSMs, but also QSMs have been identified in some bacteria-related disorders. Therefore, quantitative detection of QSMs present in clinical samples may be a useful tool in the investigation and monitoring of bacteria-related diseases, thus prompting the use of QSMs as biomarkers of disease. Herein, we have developed and utilized whole-cell biosensing systems and protein based biosensing systems to detect QSMs in clinical samples, such as, saliva, stool, and bowel secretions. Additionally, since bacteria are responsible for food spoilage, we employed the developed biosensing systems to detect QSMs in food samples and demonstrated their applicability for early identification of food contamination. Furthermore, we have utilized these biosensing systems to screen antibacterial compounds employed for food preservation, namely, generally regarded as safe (GRAS) compounds, for their effect on quorum sensing.

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Juliani, Didier. « Etude de la fragmentation lors de la réaction 12C+12C à 95 MeV/n et 400MeV/n dans le cadre de la hadronthérapie ». Phd thesis, Université de Strasbourg, 2013. http://tel.archives-ouvertes.fr/tel-01062704.

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La hadronthérapie est une méthode de radiothérapie utilisant des ions (ici le carbone) comme faisceau plutôt que des rayons X plus conventionnels pour le traitement des cancers. Étant donné le parcours spécifique des ions dans la matière, ils permettent de traiter des tumeurs profondes dans des zones délicates telles que le cerveau par exemple. Ceci est complémentaire à tout ce qui existe depuis des dizaines d'années (intervention chirurgicale, rayons X, chimiothérapie). Deux futurs centres de traitement et de recherche (ARCHADE à Caen et ETOILE à Lyon) seront opérationnels en France à partir de 2018 en ce qui concerne ARCHADE afin de profiter des avancées récentes et de poursuivre les recherches sur cette méthode. La perte d'énergie des ions carbone dans la matière suit la loi de Bethe-Bloch, le maximum de dépôt d'énergie se situant dans une zone restreinte appelée " pic de Bragg ". En modulant la position et l'énergie du faisceau, il est possible d'irradier l'ensemble du volume de la tumeur. Cependant, les réactions nucléaires de l'ion carbone dans les tissus entrainent la production de fragments plus légers (H, He, Li etc.) qui déposent leur énergie au-delà du pic de Bragg. Les modèles implémentés dans les codes de simulation couramment utilisés en hadronthérapie (FLUKA, GEANT4 etc.) sont incapables de reproduire en même temps les distributions angulaires des fragments générés ainsi que les distributions en énergie. Le fait de ne pas reproduire fidèlement ce phénomène de fragmentation nuit à la précision des systèmes de planification de traitement utilisés cliniquement. En effet, une mauvaise estimation du processus de fragmentation entraine un biais dans le calcul de la dose déposée dans les cellules saines en arrière du pic de Bragg. Ainsi, afin de mieux contraindre les modèles, deux expériences de mesure de sections efficaces de fragmentation du carbone ont été menées. La première en mai 2011 avec un faisceau à 95MeV/n au GANIL à CAEN avec les collaborateurs du LPC Caen et la seconde en août 2011 avec un faisceau à 400 MeV/n au GSI à Darmstadt, avec la collaboration FIRST. L'expérience E600 étudie la fragmentation des ions du faisceau de carbone à 95 MeV/n dans différentes cibles minces (Au, C, , Ti etc.) correspondant aux différents constituants élémentaires du corps humain. Les différents fragments sont détectés à l'aide de cinq télescopes. Chacun d'eux est constitué de 3 étages (2 détecteurs silicium et un scintillateur CsI) afin de faire des mesures de perte d'énergie et d'énergie totale permettant une identification par la méthode du ΔE-E. Ces télescopes étaient disposés sur des raquettes pilotées à distance afin de pouvoir modifier leur position angulaire par rapport à la position de la cible. Ainsi, les taux de production des différents fragments permettent de remonter aux sections efficaces de fragmentation doublement différentielles (en énergie et en angle). [...]

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Aljawasim, Baker Diwan Getheeth. « Evaluation of PCR-Based Methods for Rapid, Accurate Detection and Monitoring of Verticillium Dahliae in Woody Hosts by Real-Time Polymerase Chain Reaction ». UKnowledge, 2014. http://uknowledge.uky.edu/plantpath_etds/13.

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Verticillium wilt, caused by Verticillium dahliae Kleb, is one of the most economically important diseases of woody hosts such as ash (Fraxinus spp.), sugar maple (Acer saccharum), and redbud (Cercis canadensis). The causal agent has a broad host range, including not only woody hosts but also important vegetable and field crops, and it is distributed worldwide. Diagnosis of V. dahliae in infected woody hosts is often based on the occurrence of vascular discoloration and time-consuming isolation. However, not all woody hosts exhibit vascular discoloration symptoms, and not all vascular discoloration symptoms are due to infection by V. dahliae. In this study, real-time PCR-based assays were evaluated and employed for rapid and accurate detection of V. dahliae in different woody hosts. DNA was extracted in large quantities from presumptively infected woody hosts by collecting drill-press shavings from sample tissue, bead-beating, and extracting using a CTAB method. Six published primer sets were evaluated against genomic DNA of V. dahliae as well as selected negative controls, and two sets (VertBt-F/VertBt-R and VDS1/VDS2) showed promise for further evaluation using DNA extracts from field samples. The VertBt primers amplified a species-specific 115-bp fragment of the expected size, while the VDS primers amplified the expected specific 540-bp fragment. However, the VertBt primer set exhibited higher sensitivity in detection of V. dahliae even in asymptomatic trees. The PCR-based methods developed here could be used as rapid tools for pathogen detecting and monitoring, thus informing plant pathogen management decisions.

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Krasuski, Adam, et Piotr Wasilewski. « The Detection of Outlying Fire Service’s Reports ». Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-113145.

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We present a methodology for improving the detection of outlying Fire Service’s reports based on domain knowledge and dialogue with Fire & Rescue domain experts. The outlying report is considered as element which is significantly different from the remaining data. Outliers are defined and searched on the basis of domain knowledge and dialogue with experts. We face the problem of reducing high data dimensionality without loosing specificity and real complexity of reported incidents. We solve this problem by introducing a knowledge based generalization level intermediating between analysed data and experts domain knowledge. In the methodology we use the Formal Concept Analysis methods for both generation appropriate categories from data and as tools supporting communication with domain experts. We conducted two experiments in finding two types of outliers in which outliers detection was supported by domain experts.

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Notarangelo, Michela. « Exploiting extracellular vesicles for ultrasensitive detection of cancer biomarkers from liquid biopsies ». Doctoral thesis, Università degli studi di Trento, 2019. http://hdl.handle.net/11572/243195.

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Extracellular vesicles (EVs) are small membrane-surrounded structures containing transmembrane proteins and enclosing cytosolic proteins and nucleic acids. They are released in the extracellular space by both normal and neoplastic cells and play an important role in cell-cell communication in numerous physiological processes and pathological conditions, through the transfer of their functional cargo to recipient cells. EVs are highly abundant in biological fluids, and even more represented in cancer patients’ biofluids, therefore many studies suggested that they can be instrumental in liquid biopsies as prognostic markers or for early detection of tumors. Moreover, being secreted by potentially all the cells, they can serve in oncology to represent the tumor heterogeneity, which is underestimated by the current diagnostic tools. Given their small size, EVs are difficult to isolate in a high-throughput way and, therefore, one of the main obstacles to their clinical application, is that the existing isolation methods are impractical. During these years, I worked at the development and optimization of a novel technique that allows purification of heterogeneous EVs from biological fluids in an efficient, fast and reproducible way. This technique, named Nickel-Based Isolation (NBI), is a biochemical assay that allows obtaining polydisperse EVs in a physiological pH solution, therefore, preserving their morphology, heterogeneity, and stability. We tested and optimized this assay in protein-enriched systems and comparing it to the techniques currently used to characterize and measure EVs, such as flow cytometry and Tunable Resistive Pulse Sensing. We challenged the reproducibility of this method by isolating EVs from different biological fluids. Interestingly, the EVs purified with NBI result more intact and stable compared to the ones obtained with other methods, and can be studied in a clinical setting and used as an innovative tool for detection of molecules associated with diseases. We demonstrated the specificity of the procedure by using individual isolated vesicles in biochemical and molecular assay, optimized to characterize the biological content of EVs. We were able to detect picomolar concentration of PSMA on 105 EVs isolated from plasma of prostate cancer patients and BRAF-V600E transcript in just 103 EVs from the plasma of colon cancer patients, reaching unprecedented matching with tissue biopsy results. We also investigated the transcriptome of EVs isolated from glioblastoma cancer stem cells, in order to exploit the potential of EVs as diagnostic markers.

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Guo, Jing. « MULTI-MODE SELF-REFERENCING SURFACE PLASMON RESONANCE SENSORS ». UKnowledge, 2013. http://uknowledge.uky.edu/ece_etds/13.

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Surface-plasmon-resonance (SPR) sensors are widely used in biological, chemical, medical, and environmental sensing. This dissertation describes the design and development of dual-mode, self-referencing SPR sensors supporting two surface-plasmon modes (long- and short-range) which can differentiate surface binding interactions from bulk index changes at a single sensing location. Dual-mode SPR sensors have been optimized for surface limit of detection (LOD). In a wavelength interrogated optical setup, both surface plasmons are simultaneously excited at the same location and incident angle but at different wavelengths. To improve the sensor performance, a new approach to dual-mode SPR sensing is presented that offers improved differentiation between surface and bulk effects. By using an angular interrogation, both surface plasmons are simultaneously excited at the same location and wavelength but at different angles. Angular interrogation offers at least a factor of 3.6 improvement in surface and bulk cross-sensitivity compared to wavelength-interrogated dual-mode SPR sensors. Multi-mode SPR sensors supporting at least three surface-plasmon modes can differentiate a target surface effect from interfering surface effects and bulk index changes. This dissertation describes a tri-mode SPR sensor which supports three surface plasmon resonance modes at one single sensing position, where each mode is excited at a different wavelength. The tri-mode SPR sensor can successfully differentiate specific binding from the non-specific binding and bulk index changes.

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MALAGO', Marco. « FAULT DETECTION IN HEAVY DUTY WHEELS BY ADVANCED VIBRATION PROCESSING TECHNIQUES AND NUMERICAL MODELLING ». Doctoral thesis, Università degli studi di Ferrara, 2012. http://hdl.handle.net/11392/2389246.

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The research work reported in this thesis aims at developing a methodology and a procedure for the condition monitoring and diagnostics of heavy-duty wheels based on vibration measurements at the end of the production line. The early detection of manufacturing anomalies is necessary to sensibly reduce the time/money lost due to possible problems that can rise up during the operating phases. Heavy-duty wheels are used in applications as automatic vehicles and motor trucks and are mainly composed of a polyurethane tread glued to a cast iron hub. The adhesive application between tread and hub is the most critical assembly phase, since it is completely made by an operator and a contamination of the link area between polyurethane and cast iron may happen. Furthermore the presence of rust on the hub surface can contribute to worsen the adherence interface and to reduce the operating life. As the author is aware, studies by other researchers concerning the fault detection in heavy-duty wheels are not present in literature. In order to develop a detection procedure, several wheels with different types of faults have been manufactured “ad hoc” with anomalies similar to real ones. Such anomalies consist of incorrectly adherence zones between tread and hub as well as localized or distributed rust on the hub surface. Numerous experimental tests have been carried out in order to identify the vibration effects of these defects as a function of fault type and dimensions. The thesis concerns the detection and diagnostic capability of different vibration processing techniques using well-suited indicators and determining pass/fail decision thresholds through the Tukey’s non-statistical method. Contemporary, an accurate dynamic analysis of this mechanical system has been conducted - both experimentally through modal analysis techniques and numerically through finite element method - in order to establish the influence of the dynamic properties of the system components (namely heavy-duty wheel, support, frame of the test set up) on the measured vibratory signal. Based on this dynamic characterization, a multibody model of the system has been developed: the heavy-duty wheel is considered as rigid and the yielding part is focused in the contact patch between wheel and drum. A non-linear elastic contact algorithm is adopted, based on stiffness properties previously extracted from static tests conducted on both material specimens and complete components. The model makes it possible to reproduce the vibration effects of the defects and to simulate signal modifications due to different component materials and design. as Synchronous Average and Cyclostationarity Analysis,

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Daphney, Cedrick M. « The Fate and Transport of Chemical Warfare Agent Simulants in Complex Matrices ». Digital Archive @ GSU, 2008. http://digitalarchive.gsu.edu/chemistry_theses/13.

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Experiments to determine the fate and transport of the chemical warfare agent (CWA) simulants diisopropyl fluorophosphate (DIFP), O,S-diethyl methylphosphonothioate (OSDEMP), and 2-Chloroethyl ethyl sulfide (CEES) exposed to complex matrix systems are reported here. The aforementioned simulants were used in place of O-isopropyl methylphosphonofluoridate (GB), O-Ethyl S-(2-diisopropylaminoethyl) methylphosphonothiolate (VX), and Bis (2-chloroethyl) sulfide (HD), respectively. At ambient temperature, simulant pH (2.63 to 12.01) and reaction time (1 minute to 24 hours) were found to have significant influence on the recovery of simulants from charcoal, plastic, and TAP (butyl rubber gloves) in aqueous media. Buffer systems used included, phosphate, acetate, borate, and disodium tetraborate. Organic extractions were carried out using a 90:10 (v/v) dichloromethane / 2-propanol solution. All extracts were analyzed with a gas chromatograph equipped with flame ionization and flame photometric detectors (GC-FID-FPD). The FPD was used to determine the amount of simulant recovery.

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Di, Lodovico Francesca Romana. « Search for Higgs bosons within and beyond the Standard Model with the L3 Detector at 130 GeV <̲ {sqrt}S <̲ 183 GeV / ». Zürich, 1998. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=12862.

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Kastlander, Johan. « In situ measurements of radionuclide concentration in soil : An investigation into detector properties and methods ». Doctoral thesis, Stockholms universitet, Fysikum, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-47398.

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In case of a release of radioactive nuclides into the environment it is necessary to have reliable methods to estimate the potential effect on people and the ecosystem. In this context the total activity deposited, the elemental composition and the depth distribution are of importance. An efficient in situ method to estimate the average contamination over larger areas using high purity germanium (HPGe) detectors has been developed. The method combines simulation of photon transport with measured detector properties. The total activity of 137Cs determined from gamma-ray spectra recorded in situ are compared to results from soil sampling. Another in situ method has been developed to determine the depth distribution of a radionuclide contamination, using an array of small detectors inserted into the ground, as an alternative to the standard procedure of soil sampling. The possibility to use cadmium telluride (CdTe) detectors as well as lanthanum bromide (LaBr3) detectors has been investigated. As a demonstration of the developed method the small-scale variation of the activity distributions in an area covering 350 m2 have been measured and is compared to results obtained by other methods.
At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Submitted.

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Mainardi, Chiara. « Detection of an immunological response against TEL/AML1 fusion protein ». Doctoral thesis, Università degli studi di Padova, 2017. http://hdl.handle.net/11577/3424771.

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Immunotherapy represents a therapeutic option for subgroups of paediatric patients with leukaemia who, despite the impressing advances of the last decades in the field, still show a poor prognosis because of high risk-disease or relapse. A deeper understanding of how the immune system physiologically recognizes and eradicates tumour cells is mandatory. Peptidic antigens are of great interest in the field of immunotherapy because they could be used as vaccines to boost immunity. TEL/AML1 mutant protein, whose sequence is known, is the result of a balanced t(12;21) translocation which generates a fusion gene. Peptides can be artificially synthetized from TEL/AML1 fusion protein and their HLA-binding capacity and immunogenicity can be predicted through bioinformatic tools. This project aimed to investigate whether the excellent prognosis showed by patients who suffer from a B-lineage ALL harbouring the TEL/AML1 mutation could be related to an immune response against peptidic antigens derived from the TEL/AML1 mutant protein. For such purpose, 8 priming experiments were performed with healthy donors’ leucocytes. Six experiments were carried out according to a dendritic cells-mediated protocol, whereas two experiments were performed according to a beads-mediated protocol. Successfully primed lymphocytes (identified by mean of intracellular cytokines production) were selected through flow cytometric sorting and single-cell seeded in order to get T-cell clones. This was possible in 3 out of 8 priming experiments. Growing T-cell clones were tested after stimulation with peptides (or through tetramer staining) but they did not show enough specificity. We also tried to show an immune response against fusion peptides in peripheral blood leucocytes of patients who survived a TEL/AML1 positive B-lineage ALL, through exposure to peptides and a short course stimulation with cytokines. We tested 22 patients, but unfortunately we weren’t able to show an answer against fusion peptides in any of them. Possible reasons might be the lack of specificity of the activation markers we used to identify reactive cells, the not enough restrictive gates we used for sorting, the fact that the HLA super type B*07 (for which the restricted peptides had the best prediction score) was underrepresented in our patients’ cohort. We suggest to perform further experiments using new activation markers, such as CD25 or PD-L1, or different techniques to identify reactive cells (such as Elispot), to use more restrictive gates for sorting and to exploit the beads priming protocol. In order to sample such lymphocyte populations (i.e. antigen specific T-cells) with an extremely low frequency, a possibility may be collect repeatedly blood samples from the same patient at different time points. Further studies are warranted to test the hypothesis of an autologous, spontaneously arising immune response against TEL/AML1 fusion peptides as reason for the good prognosis of TEL/AML1 positive leukaemia. Another possible approach in order to validate fusion peptides might be to test them in a situation of HLA B*07 mismatch between lymphocytes and APCs. The clinical counterpart could be the generation of reactive T-cell clones, cloning of their TCR and its transduction in the patient’s or donor’s lymphocytes, the latter in the perspective of a post-hematopoietic stem cell transplantation adoptive immunotherapy.
L’immunoterapia costituisce un’opzione terapeutica per alcuni sottogruppi di pazienti con leucemia dell’età pediatrica i quali, nonostante i notevoli progressi degli ultimi decenni, ancora non mostrano una prognosi soddisfacente perché affetti da malattia ad alto rischio oppure da ricaduta. Una comprensione più profonda di come il sistema immunitario fisiologicamente riconosce ed elimina le cellule tumorali è essenziale. Gli antigeni peptidici sono di grande interesse nel settore dell’immunoterapia perché possono essere utilizzati come vaccini per potenziare l’immunità. La proteina mutante TEL/AML1, la cui sequenza è nota, è il risultato di una traslocazione bilanciata t(12;21) che genera un gene di fusione. Dalla proteina di fusione TEL/AML1 si possono sintetizzare artificialmente peptidi, la cui capacità di legare le molecole HLA ed immunogenicità si può prevedere attraverso strumenti bioinformatici. Questo progetto ha l’obiettivo di indagare se l’eccellente prognosi dei pazienti affetti da leucemia linfoblastica di linea B con la mutazione TEL/AML1 possa essere correlata ad una risposta immunologica nei confronti di peptide di fusion derivati dalla proteina mutante TEL/AML1. A tale scopo, sono stati realizzati 8 esperimenti di priming con leucociti di donatori sani. Sei sono stati realizzati secondo un protocollo mediato da cellule dendritiche, mentre altri due esperimenti sono stati condotti secondo un protocollo mediato da beads. I linfociti responsivi al processo di priming (identificati mediante la produzione intracellulare di citochine) sono stati selezionati mediante sorting citofluorimetrico e coltivati a singola cellula in modo da ottenete cloni T-cellulari. Ciò è stato possibile in 3 esprimenti su 8. I cloni T-cellulari con evidenza di crescita sono stati testati dopo re-stimolazione con i peptidi (o mediante tetramer-staining) ma non hanno dimostrato sufficiente specificità- Abbiamo inoltre provato a dimostrare una risposta immunologica nei confronti dei peptidi di fusione nei leucociti (da sangue periferico) di pazienti con leucemia linfoblastica di linea B TEL/AML1 positiva in remissione, mediante esposizione ai peptidi e una breve stimolazione con citochine. Sono stati testati 22 pazienti, ma purtroppo non è stato possibile evidenziare una risposta nei confronti dei peptidi di fusione in nessuno di loro. Possibili spiegazioni potrebbero essere la mancanza di specificità dei marcatori di attivazione che sono stati utilizzati per identificare le cellule reattive, i gate non sufficientemente restrittivi utilizzati per il sorting, il fatto che il supertipo HLA B*07 (i peptidi B*07 ristretti avevano il migliore score predittivo) era sotto-rappresentato nella coorte di pazienti presa in esame. Ci riproponiamo di realizzare ulteriori esperimenti utilizzando nuovi marcatori di attivazione, come CD25 o PD-L1, oppure differenti tecniche per identificare le cellule reattive (come l’Elispot), di usare gates più restrittivi per il sorting e di utilizzare esclusivamente il protocollo mediato da beads per il priming. Per riuscire a includere nel campione popolazioni linfocitarie (cellule T antigene-specifiche) la cui frequenza è estremamente bassa, una possibilità potrebbe essere eseguire prelievi ematici ripetuti nel tempo nello stesso paziente. Sono necessari ulteriori studi per testare l’ipotesi di una risposta immune autologa, spontanea, nei confronti dei peptidi di fusione TEL/AML1 come spiegazione della buona prognosi della leucemia linfoblastica di linea B TEL/AML1 positiva. Un altro possibile approccio per validare i peptidi di fusione potrebbe essere quello di testarli in una situazione di HLA B*07 mismatch tra linfociti ed APCs. La ricaduta clinica potrebbe essere la generazione di cloni T-cellulari dalle cellule reattive al priming, il clonaggio del loro TCR e la sua transduzione nei linfociti del paziente o del suo donatore, in quest’ultimo caso nella prospettiva di un’immunoterapia adottiva post-trapianto di cellule staminali ematopoietiche.

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FIGUEIRA, RUBENS C. L. « Inventario de radionuclideos artificiais em agua do mar e sedimentos da costa sul do Brasil ». reponame:Repositório Institucional do IPEN, 2000. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10817.

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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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Beresford, Lydia Audrey. « Searches for dijet resonances using √s = 13 TeV proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider ». Thesis, University of Oxford, 2017. http://ora.ox.ac.uk/objects/uuid:c516b04b-2763-487a-a633-6c506cec93ad.

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This thesis presents three searches for new resonances in dijet invariant mass spectra. The spectra are produced using √s = 13 TeV proton-proton collision data recorded by the ATLAS detector. New dijet resonances are searched for in the mass range 200 GeV to 6.9 TeV in mass. Heavy new resonances, with masses above 1.1 TeV, are targeted by a high mass dijet search. Light new resonances, with masses down to 200 GeV, are searched for in dijet events with an associated high momentum object (a photon or a jet) arising from initial state radiation. The associated object is used to efficiently trigger the recording of low mass dijet events. All of the analyses presented in this thesis search for an excess of events, localised in mass, above a data-derived estimate of the smoothly falling QCD background. In each search no evidence for new resonances is observed, and the data are used to set 95% C.L. limits on the production cross-section times acceptance times branching ratio for model-independent Gaussian resonance shapes, as well as benchmark signals. One particular benchmark signal which is considered in all of the searches is an axial-vector Z' dark matter mediator model whose parameter space is reduced due to the results presented in this thesis.

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Jones, Sarah, et Sarah Jones. « Searching for Vector-Like Quarks Using 36.1 fb^{-1} Of Proton-Proton Collisions Decaying to Same-Charge Dileptons and Trileptons + b-jets at √s = 13 TeV with The ATLAS Detector ». Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/626353.

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Since the discovery of the Higgs boson in 2012, the search for new physics beyond the Standard Model has been greatly intensified. At the CERN Large Hadron Collider (LHC), ATLAS searches for new physics entail looking for new particles by colliding protons together. Presented here is a search for a new form of quark matter called Vector-like Quarks (VLQ), which are hypothetical particles that are expected to have mass around a few TeV. VLQ can come in a variety of forms and can couple to their Standard Model (SM) quark counterparts, particularly to the third generation. They are necessary in several beyond the SM theories in order to solve the hierarchy problem. This search uses 36.1 fb−1of proton-proton collision data collected with the ATLAS detector at the LHC from August 2015 to October 2016. Only events with two leptons of the same charge, or three leptons, plus b-jets and high missing transverse energy are considered in the main analysis. This signature is rarely produced in the SM, which means the backgrounds in this analysis are relatively low. This analysis is sensitive to specific predicted decay modes from pair production of an up-type VLQ with a charge of +2/3, T, an up-type VLQ with a charge of +5/3, T5/3, and a down-type quark with a charge of −1/3, B, as well as single production of T5/3. There is another theorized VLQ that this analysis is not sensitive to: B−4/3, due to its primary decay mode, which is unable to produce the final-state signature of interest. The results from this analysis suggest only a slight deviation of data from SM backgrounds reaching as high as 1.89σ, which does not indicate evidence for VLQ. A mostly frequentist statistical technique, called the CLS Method, is used to interpret the data and set limits on the T, B, and T5/3 signal models. Using this method, exclusion limits are set at the 95% confidence level, effectively excluding T mass below 0.98 TeV, T5/3 mass below 1.2 TeV, and B mass below 1.0 TeV, assuming singlet branching ratios. Also, branching ratio independent limits are set on the T and B VLQ.

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ALMEIDA, JAMILLE da S. « Estudo das impurezas radioativas gama emissoras presentes nos radiofármacos produzidos no IPEN-CNEN/SP ». reponame:Repositório Institucional do IPEN, 2017. http://repositorio.ipen.br:8080/xmlui/handle/123456789/28039.

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Este trabalho tem como objetivo investigar a concentração de impurezas radioativas gama emissoras presentes nas soluções dos radiofármacos produzidos no Instituto de Pesquisas Energéticas e Nucleares - IPEN em São Paulo. Para que este radiofármaco possa ser utilizado adequadamente, sua qualidade deve ser avaliada de acordo com os procedimentos estabelecidos de acordo com os \"Requisitos Gerais para a Competência de Laboratórios de Teste e Calibração\", ISO / IEC 17025: 2005 e pelas \"Boas Práticas de Fabricação\" (BPF), controladas pela ANVISA (Agência Nacional de Vigilância Sanitária), no Brasil. Para determinar a atividade, dos radiofármacos das impurezas gama emissoras, foi utilizado um espectrômetro gama de alta resolução em duas distâncias fonte-detector; uma de 18 cm e outra de 1,7 cm. Para a distância de 18 cm, o espectrômetro HPGe foi calibrado com energias gama entre 81 kev e 1408 kev, medindo ampolas seladas de 60Co, 133Ba, 137Cs e 152Eu, padronizadas no Laboratório de Metrologia Nuclear (LMN) do IPEN. Para impurezas com baixas atividades, utilizou a distância fontedetector de 1,7 cm. A esta distância, o efeito soma em cascata é muito elevado, tornando difícil a medição das ampolas de calibração padrão, com isso, a curva de eficiência do espectrômetro foi obtida por um código de simulação de Monte Carlo, desenvolvido no IPEN. Neste código, todos os detalhes do sistema de detecção são modelados e as curvas de resposta para raios X e raios gama são calculadas pelo código de transporte de radiação MCNPX. Os espectros gama foram analisados pelo programa Alpino, que aplica o método de integração numérica da área sob os fotopicos de absorção total. Para as impurezas gama emissoras não detectadas visualmente, os limites de detecção foram calculados a partir da taxa de contagem de fundo, sob a área do pico de interesse. As soluções radioativas analisadas foram 67Ga,99Mo, 99mTc, 111In, 131I, 153Sm, 177Lu e 201Tl. Os resultados da relação entre a atividade do radionuclídeo em análise e as impurezas identificadas apresentaram acordo com os certificados de análise dos fabricantes, assim como, com as especificações da ANVISA.
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP

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Napolitano, Fabrizio [Verfasser], et Oleg [Akademischer Betreuer] Brandt. « Search for Dark Matter produced in association with a hypothetical Dark Higgs Boson decaying to W ± W ∓ or ZZ boson pairs in the fully hadronic final state at √s = 13 TeV using 139 fb−1 of pp collisions recorded with the ATLAS Detector / Fabrizio Napolitano ; Betreuer : Oleg Brandt ». Heidelberg : Universitätsbibliothek Heidelberg, 2020. http://d-nb.info/1217539727/34.

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CARRA, SONIA. « SEARCH FOR ELECTROWEAK PRODUCTION OF SUPERSYMMETRIC PARTICLES AT THE LHC RUN 2 WITH THE ATLAS DETECTOR ». Doctoral thesis, Università degli Studi di Milano, 2019. http://hdl.handle.net/2434/608194.

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Two closely related searches for the electroweak production of Supersymmetric particles are presented in this manuscript. The analyses are based on the proton-proton collision data from the Large Hadron Collider Run 2, with a center-of-mass energy of 13 TeV, collected by the ATLAS experiment. Different Supersymmetric signal models are considered. The first search targets the pair production of either the Supersymmetric partners of the leptons (sleptons) or the $W$ boson and charged Higgs boson super-partners (charginos). In the latter case, the decay of charginos via sleptons is assumed. The search uses data collected by ATLAS between 2015 and 2016, with an integrated luminosity of 36.1 fb$^{-1}$. The second search targets the direct production of chargino pair with $W$ boson mediated decay. The analysis for the observation of the process was performed using the data collected by ATLAS between 2015 and 2017, reaching an integrated luminosity of 80.5 fb$^{-1}$. The signature, common to all the SUSY signal models considered, consists of two charged leptons (electrons or muons) and missing transverse energy. No significant fluctuation above the Standard Model prediction was observed in the analyses. New exclusion limits, tighter than the previously available results, were placed on the masses of the SUSY particles: slepton masses up to 500 GeV are excluded at 95%~CL. Chargino masses up to 700 GeV are excluded in the case of the decay mediated by a slepton, while considering the $W$ boson mediated decay the limit on the chargino mass is 410 GeV.

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Skwarcan-Bidakowski, Alexander. « Exotic Decays of a Vector-liketop Partner at the LHC ». Thesis, Uppsala universitet, Högenergifysik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-392988.

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An evaluation of how sensitive some ATLAS searches for new physics are to a new beyond standard model (BSM) vector-like quark (VLQ) and a pseudo Nambu-Goldstone boson (pNGB) scalar. This was done by simulating a signal containing these new particles and making a recast of it onto existing verified ATLAS searches for new physics at center-of-mass (CM) energy of 13 TeV (Run 2) at the Large Hadron Collider (LHC). Signals for recasting were tailored such that their final states would be appropriate in relation to each respective ATLAS search in order to use the same selection criteria as applied in the existing searches. The results are summarized in the form of significances (Z) for each masspoint of the new top-partner and S particle. Significances did not show any expectiation of excluding any masspoint in the examined mass range for the recasts at 95% CL. This suggests that a dedicated search for these particles in the considered masspoints would be required.

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Larabi, Islam Amine. « Nouveaux produits de synthèse : analyse, consommation et métabolisme ; Applications cliniques et médicolégales Rapid and simultaneous screening of new psychoactive substances and conventional drugs of abuse. A comparative study of Biochip Array Technology versus LC-MS/MS in whole blood and urine Development of a sensitive untargeted liquid chromatography– high resolution mass spectrometry screening devoted to hair analysis through a shared MS2 spectra database : A step toward early detection of new psychoactive substances Validation of an UPLC-MS/MS method for the determination of sixteen synthetic cannabinoids in human hair. Application to document chronic use of JWH-122 following a non-fatal overdose Development and validation of liquid chromatography-tandem mass spectrometry targeted screening of 16 fentanyl analogs and U-47700 in hair : Application to 137 authentic samples Prevalence and Surveillance of Synthetic Cathinones Use by Hair Analysis : An Update Review Prevalence of New Psychoactive Substances(NPS) and conventional drugs of abuse (DOA) in high risk populations from Paris(France) and its suburbs A cross sectional study by hair testing(2012–2017) Evaluation of drug abuse by hair analysis and self-reported use among MSM under PrEP : Results from a sub-study of the ANRS-IPERGAY trial. Hair testing for 3‑fluorofentanyl, furanylfentanyl, methoxyacetylfentanyl, carfentanil, acetylfentanyl and fentanyl by LC–MS/MS after unintentional overdose Drug‐facilitated sexual assault (DFSA) involving 4‐methylethcathinone (4‐MEC),3,4‐Methylenedioxypyrovalerone (MDPV), and doxylamine highlighted by hair analysis Metabolic Profiling of Deschloro-N-ethyl-ketamine (O-PCE) and identification of new target metabolites in urine and hair using human liver microsomes and high-resolution accurate mass spectrometry ». Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASL029.

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L’objectif de ce travail a été de développer deux approches analytiques dédiées à l’analyse toxicologique des nouveaux produits de synthèse (NPS) dans différentes matrices biologiques (sang, urine et cheveux). La première est basée sur le criblage non ciblé par chimiluminescence sur biopuces et chromatographie liquide couplée à la spectrométrie de masse haute résolution (LC-HRMS) et la deuxième correspond à un criblage ciblé par spectrométrie de masse en tandem (LC-MS/MS). Ces deux approches ont ensuite été appliquées dans des études observationnelles pour évaluer la consommation de NPS dans des populations à risques de surdosage, de pharmacodépendance ou de soumission chimique dans un contexte clinique ou médico-judiciaire.La dernière partie a été consacrée au développement d’un nouvel outil analytique de traitement des données issues de la LC-HRMS qui a permis d’étudier le métabolisme de 9 NPS in vitro sur des cultures de microsomes du foie humain (HLM) et in vivo sur des échantillons biologiques d’usagers de ces drogues. Cette dernière approche a permis la création d’une bibliothèque de spectres de haute résolution composée de 228 métabolites dont certains ont été proposés comme marqueurs pertinents d’exposition aux NPS dont ils sont issus.Ce travail a été concrétisé par la rédaction de 10 publications scientifiques et a permis d’initier plusieurs collaborations pluridisciplinaires
The aim of the present work was to develop two analytical approaches dedicated to the analysis of new psychoactive substances in different biological matrices (blood, urine and hair). The first approach is based on untargeted screening by both biochip array technology chemiluminescence assay and liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS) and the second corresponds to a targeted screening by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). These two approaches were then applied in observational studies to assess the consumption of NPS in high risk populations (overdose, drug abuse, drug facilitated crimes) in clinical and forensic settings. The last part of the work was devoted to the development of a new analytical tool for LC-HRMS data processing which made it possible to study the metabolism of 9 NPS In vitro on human liver microsomes (HLM) and In vivo in biological samples from drug users. This approach has enabled the creation of HRMS spectral library containing 228 metabolites, some of which have been proposed as relevant markers of NPS exposure.This work has resulted on 10 scientific publications and allowed to initiate many multidisciplinary collaborations

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Carvalho, Rui de Albuquerque. « 13C Isotopomer Analysis of Tissue Metabolism by direct and indirect NMR Detection ». Doctoral thesis, 1999. http://hdl.handle.net/10316/1597.

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Tese de doutoramento em Bioquímica (física Molecular) apresentada à Fac. de Ciências e Tecnologia da Univ. de Coimbra
A análise de isotopómeros por RMN constitui actualmente uma das metodologias mais promissoras para o diagnóstico clínico de disfunções metabólicas. Uma das principais vantagens desta técnica assenta no facto de fazer uso de isótopos estáveis como 13C e 2H, em vez dos marcadores radioactivos tradicionalmente usados. No entanto, a baixa sensibilidade da espectroscopia RMN e o elevado custo dos marcadores isotópicos estáveis constituem duas desvantagens significativas que têm impossibilitado a aplicação da técnica em análises clínicas de rotina. O objectivo desta investigação foi a exploração e desenvolvimento de novos métodos de detecção de 13C com sensibilidade acrescida. A estratégia geral seguida consistiu no desenvolvimento de métodos bidimensionais de correlação heteronuclear capazes de providenciar informação sobre isotopómeros a fim de poder ser utilizada em modelos metabólicos. A técnica encontrada mais adequada consiste na combinação da correlação heteronuclear HM(S)QC com a correlação homonuclear TOCSY HM(S)QCTOCSY. Esta sequência permite em cada protão uma leitura directa das populações de 13C, tanto relativas ao carbono directamente ligado como a carbonos alifáticos afastados. Foi possível o estabelecimento de correlações entre os volumes de picos cruzados da experiência HM(S)QCTOCSY e fluxos relativos de vias metabólicas associadas com o ciclo de Krebs, obtendose os mesmos fluxos que os determinados a partir de uma análise de espectros RMN de 13C unidimensionais. Este método foi aplicado a amostras de glucose obtidas do sangue após infusão de marcadores de 13C, permitindo quantificar fluxos hepáticos. Tal aplicação demonstra as possibilidades da técnica HM(S)QCTOCSY para o desenvolvimento de um método clínico automatizado de quantificação de gluconeogenese em humanos. O aumento em sensibilidade providenciado pela técnica foi demonstrado através da obtenção de importantes fluxos metabólicos a partir de um pequeno músculo soleus de ratinho de aproximadamente 10 mg, que representa uma amostra do tamanho típico de uma biópsia de tecido humano. Em conclusão, este trabalho estabeleceu as bases para a futura aplicação da análise de isotopómeros por RMN a uma variedade de doenças humanas usando amostras suficientemente pequenas e que vulgarmente se encontram disponíveis.
NMR isotopomer analysis is currently developing tnto one of the most promising tools for clinical diagnosis of metabolic dysfunctions. A major advantage of this technique resides in the use of stable isotopes like 13C and 2H, instead of the conventionally used radiotracers. Nevertheless, two major disadvantages, the inherent insensitivity of the NMR technique and the high cost of stable tracers, have circumvented routine applications of the technique in clinical settings. The goal of this research was to explore new NMR methods of 13C detection with increased sensitivity. The general approach followed consisted in the development of indirect 2D [13C,1H] heteronuclear correlation methods capable of providing 13C isotopomer information to be used in mathematical metabolic models. The most successful technique proved to be a combination of the HM(S)QC sequence with a 1H-TOCSY relay HM(S)QCTOCSY. This sequence provided a direct readout of 13C populations, both nearest neighbour and multiple bonds, from every proton in a molecule. Relationships between HM(S)QCTOCSY crosspeak volumes and relative flux through pathways associated with the Krebs cycle were simple and provided equivalent results to those derived from conventional 1D 13C NMR spectra. This method was applied to derive hepatic metabolic fluxes from glucose samples obtained from blood after infusion of 13C tracers, demonstrating the feasibility of an automated clinical method to evaluate gluconeogenesis in humans by HM(S)QCTOCSY. The enhanced sensitivity of the technique was demonstrated by deriving relevant metabolic flux information from a small mouse soleus muscle of approximately 10 mg, a sample size typical of a human tissue biopsy. In summary, this work has laid the groundwork for extending 13C isotopomer analysis to a variety of human diseases by using modest sized samples that are readily available clinically.

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Weinhold, Mirko [Verfasser]. « Characterization of chitosan using triple detection size-exclusion chromatography and 13C-NMR spectroscopy / Mirko Weinhold ». 2010. http://d-nb.info/101131102X/34.

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Jordaan, Maraliese. « Diagnosis of Helicobacter pylori infection with the 13c-urea breath test analysis by means of gas chromatography with mass selective detection / by Maraliese Jordaan ». 2008. http://upetd.up.ac.za/thesis/available/etd-08052008-081439.

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HOSEK, TOMAS. « Development of new NMR methods to study intrinsically disordered proteins ». Doctoral thesis, 2015. http://hdl.handle.net/2158/969485.

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Murrali, Maria Grazia. « Characterization of intrinsically disordered proteins by nuclear magnetic resonance spectroscopy ». Doctoral thesis, 2019. http://hdl.handle.net/2158/1179640.

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During my doctorate, I focused my studies on the development of NMR methods for the characterization of IDPs and on their application to study challenging cases. The combination of 13C detection with new hardware tools such as Multiple Receivers, and new software tools such as Automated Projection, led to new strategies to speed up NMR experiments. Moreover, modification of base pulse sequences led to simple 13C NMR experiments for the characterization of proline residues, that are highly abundant in IDPs and less straightforward to be investigated with standard HN-based NMR experiments. Together with the development of new methods, I worked on their application to study different aspects of IDPs function.NMR spectroscopy was used for the characterization of a large viral disordered protein, and the study of an unexpected liquid-liquid phase transition likely relevant in the biological mechanism of viral infection. Exploiting NMR we were able to study the interaction between a disordered protein involved in Parkinson’s disease and a small molecule that can be a potential drug to contrast the pathology, as well as the interaction between an oncogenic viral protein and the disordered region of a transcriptional coactivator. These interesting applications demonstrate once again the importance of NMR spectroscopy for studying IDPs, adding small but important pieces in the knowledge about the role of protein disorder in biology.

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Schiavina, Marco. « High-Resolution tools to target intrinsically disordered proteins ». Doctoral thesis, 2021. http://hdl.handle.net/2158/1252088.

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Nuclear Magnetic Resonance (NMR) is one of the most powerful techniques exploited in structural biology. While the NMR strategies for the study of folded proteins are well established, Intrinsically Disordered Proteins (IDPs) pose new challenges to the technique. Special precautions must be taken due to the lack of 3D structure and to the high flexibility provided by these macromolecules. In this frame 13C direct detection represents one of the best options to deal with the structural and dynamic features of IDPs. However, many steps forward have still to be taken to expand the NMR toolbox for the study of this class of biologically relevant proteins. In this doctoral thesis, my contribution to the advancement of NMR spectroscopy for the study of IDPs is described. Mainly, I’ve focused on the development and application of new NMR methods. The new strategies enable the characterization of dynamic processes, facilitate the acquisition of spectra with high content of information in a reduced time and allow the identification of new key motifs in IDPs. Moreover, the outcomes from the study of two biologically relevant viral proteins are presented. Through the proposed advances new motifs are identified in different IDPs, providing information of general interest and demonstrating the general applicability of these methods.

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PIAI, ALESSANDRO. « Characterizing structural disorder through NMR : new methods and applications ». Doctoral thesis, 2015. http://hdl.handle.net/2158/1015862.

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Intrinsically Disordered Proteins (IDPs) are flexible proteins that challenge structural biology due to the fact that they cannot be studied with the standard methods developed to characterize well-folded proteins. In the last decades, the discovery of their widespread presence and involvement in many biological functions, despite their deviation from the structure-function paradigm, has pushed the scientific community towards a growing acceptance of the importance of IDPs and to the development of new tools for studying their structure, dynamics and functions. In this context, Nuclear Magnetic Resonance (NMR) spectroscopy plays the leading role of most suitable technique to characterize IDPs. In this doctoral thesis, my contribution to the advancement of NMR spectroscopy, achieved by developing new experiments to study IDPs, is described. The new methods enable the characterization of structural disorder and allow to address topics of general interest such as the study of protein linkers and low-complexity regions, two areas of high biological relevance for which only very limited atomic resolution information is available so far. The methodological progress in NMR and the findings on the studied IDPs reported here give a contribution to the discovery of new roles for structural disorder and prompt towards an unified understanding of structure-dynamicsdisorder/function relationships.

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Pourtangestani, Khadijeh. « Optimization of plastic scintillator thicknesses for online beta detection in mixed fields ». Thesis, 2010. http://hdl.handle.net/10155/138.

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For efficient beta detection in a mixed beta gamma field, Monte Carlo simulation models have been built to optimize the thickness of a plastic scintillator, used in whole body monitor. The simulation has been performed using MCNP/X code and different thicknesses of plastic scintillators ranging from 150 to 600 um have been used. The relationship between the thickness of the scintillator and the efficiency of the detector has been analyzed. For 150 m thickness, an experimental investigation has been conducted with different beta sources at different positions on the scintillator and the counting efficiency of the unit has been measured. Evaluated data along with experimental ones have been discussed. A thickness of 300 um to 500 um has been found to be an optimum thickness for better beta detection efficiency in the presence of low energy gamma ray.
UOIT

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Pan, Ming. « Research on detecting mechanism for Trojan horse based on PE file ». Thèse, 2009. http://constellation.uqac.ca/138/1/030120792.pdf.

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As malicious programs, Trojan horses have become a huge threat to computer networks security. Trojan horses can easily cause loss, damage or even theft of data because they are usually disguised as something useful or desirable, and are always mistakenly activated by computer users, corporations and other organizations. Thus, it is important to adopt an effective and efficient method to detect the Trojan horses, and the exploration of a new method of detection is of greater significance. Scientists and experts have tried many approaches to detecting Trojan horses since they realized the harms of the programs. Up to now, these methods fall mainly into two categories [2]. The first category is to detect Trojan horses through checking the port of computers since the Trojan horses send out message through computer ports [2]. However, these methods can only detect the Trojan horses that are just working when detected. The second class is to detect Trojan horses by examining the signatures of files [2] [19], in the same way as people deal with computer virus. As new Trojan horses may contain unknown signatures, methods in this category may not be effective enough when new and unknown Trojan horses appear continuously, sending out unknown signatures that escape detection. For the above-mentioned reasons, without exception, there are limitations in the existing methods if the un-awakened and unknown Trojan horses are to be detected. This thesis proposes a new method that can detect un-awakened and unknown Trojan horses- the detection by using of a file's static characteristics. This thesis takes PE file format as the object of the research, because approximately 75% of personal computers worldwide are installed the Microsoft Windows [4], and that Trojan horses usually exist as a Portable Executable (PE) file in the Windows platform. Based on the (PE) file format, my research gets all the static information of each part of PE file which is characteristic of a file. Then, this static information is analyzed by the intelligent information processing techniques. Next, a detection model is established to estimate whether a PE file is a Trojan horse. This model can detect the unknown Trojan horses by analyzing static characteristics of a file. The information that is used to verify detecting model is new and unknown to the detecting model; in other words, the information is not used during the training of the model. The thesis is organized as follows. First, this thesis discusses the limitations of traditional detection techniques, related works of research, and a new method to detect Trojan horse based on file's static information. Second, the thesis focuses on the research of the Trojan horse detecting models, covering the extracting of the static information from PE file, choice of intelligent information processing techniques, and setting up the Trojan horse detecting model. Lastly, the thesis discusses the direction of future research in this field.

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Dong, Hao. « Indoor Navigation System for the Visually Impaired with User-centric Graph Representation and Vision Detection Assistance ». 2014. https://scholarworks.umass.edu/masters_theses_2/13.

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Independent navigation through unfamiliar indoor spaces is beset with barriers for the visually impaired. Hence, this issue impairs their independence, self-respect and self-reliance. In this thesis I will introduce a new indoor navigation system for the blind and visually impaired that is affordable for both the user and the building owners. Outdoor vehicle navigation technical challenges have been solved using location information provided by Global Positioning Systems (GPS) and maps using Geographical Information Systems (GIS). However, GPS and GIS information is not available for indoor environments making indoor navigation, a challenging technical problem. Moreover, the indoor navigation system needs to be developed with the blind user in mind, i.e., special care needs to be given to vision free user interface. In this project, I design and implement an indoor navigation application for the blind and visually impaired that uses RFID technology and Computer Vision for localization and a navigation map generated automatically based on environmental landmarks by simulating a user’s behavior. The focus of the indoor navigation system is no longer only on the indoor environment itself, but the way the blind users can experience it. This project will try this new idea in solving indoor navigation problems for blind and visually impaired users.

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Wang, Siwen. « Photo- and Electro-Chemistry Methods for Waterborne Pathogen Treatment and Detection in Environmental Water ». Thesis, 2020. https://thesis.library.caltech.edu/13958/13/Siwen_Wang_2020_PhD_thesis_final.pdf.

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Waterborne disease is a global burden, which is mainly caused by waterborne pathogens disseminated through unsafe water, inadequate sanitation, and hygiene. Antibiotic resistance, which can also spread in water, has become an increasingly serious global health threat as it can prevent the effective treatment of infectious diseases. Improvements on water treatment and detection are the two critical strategies to control the surveillance of waterborne pathogens as well as antibiotic resistance bacteria and genes. The advancement in photo- and electro-chemical methods may provide more opportunities on decentralized water treatment and on-site pathogen monitoring under source-limited conditions. This thesis is dedicated to exploring the possible solutions to automatic, rapid, and easy-to-use in situ pathogen analysis for environmental water by adopting photo- or electro-chemical method, and to enhanced removal of antibiotic resistance bacteria (ARB) and antibiotic resistance genes (ARGs) from wastewater by combining photo- and electro-chemical techniques. These include removal of ARB and ARGs by UV-assisted electrochemical treatment, electrochemical cell lysis (ECL) for DNA extraction from bacteria, and sunlight-activated propidium monoazide (PMA) pretreatment for live/dead bacteria differentiation by quantitative real-time polymerase chain reaction (qPCR) detection. Both experimental approaches and computational modelling were used to evaluate the performance of the techniques and to bring more insights into the mechanism. Each study presents a demonstration on real environmental or wastewater to access the potential of their applications under complex environmental parameters.

UV-assisted electrochemical treatment for ARB and ARGs was conducted using a blue TiO₂ nanotube array (BNTA) anode. The inactivation of tetracycline- and SMX-resistant E. coli and the corresponding plasmid coded genes (tetA and sul1) damage was measured by plate counting on selective agar and qPCR, respectively. As a comparison of UV treatment alone, the enhanced reduction of both ARB and ARGs was achieved by UV-assisted electrochemical oxidation (UV-EO) without Cl⁻ and was further facilitated with the presence of Cl⁻, which is attributed to the in-situ generated oxidants by electrochemical process. Significantly slower removal of ARG than ARB was observed for both UV irradiation alone and UV-EO treatment, wherein intracellular ARG generally reduced slower than extracellular ones, and short amplicons reduced significantly slower than long ones. The predominant nucleotide damage by UV irradiation and conformational change by UV-EO treatment was visualized by DNA gel electrophoresis for treated extracellular ARGs. The mechanism on ARB and ARGs damage was further understood by computational chemical modeling. The slower reduction was found for the native bacteria and genes, tetA and sul1, in the latrine wastewater than that in laboratory-prepared buffered samples. The result emphasizes that all the UV-based techniques may only apply after other treatments to avoid the impairment by the transmittance, color, and particulate material in environmental or wastewater.

A comprehensive investigation was conducted for ECL in terms of its performance on DNA extraction from gram-negative bacteria (Escherichia coli and Salmonella Typhi) and gram-positive bacteria (Enterococcus durans and Bacillus subtilis). A milliliter-output ECL device was developed based on the disruption of the cell membrane by OH⁻ that can be generated locally at the cathode and accumulated improvingly through a cation exchange membrane. Both gram-negative and gram-positive bacteria were successfully lysed within 1 min at a low voltage of ~5 V. To better understand the pH effects on cell lysis, the pH profile at the cathode surface and in bulk cathodic effluent was simulated via hydroxide transport in the cathodic chamber. The demonstration of ECL on various environmental water sample types (including pond water, treated wastewater, and untreated wastewater) showed its potential as a prelude to nucleic-acid based analyses of waterborne bacteria in the field.

Propidium monoazide (PMA), a nucleic acid-binding dye, has been used to distinguish live from dead cells prior to PCR-based detection. To explore the off-the-grid application of PMA, sunlight was investigated for PMA activation as an alternative light source to a typical halogen lamp. PMA was successfully activated by a solar simulator, and the pretreatment conditions were optimized with respect to the PMA concentration as 80 µM and the exposure time as 10 min. The optimal PMA pretreatment was tested on four different bacteria species (two gram-positive and two gram-negative), and the effects of sunlight intensity and multi-sequential treatment were studied. Sunlight-activated PMA pretreatment was eventually demonstrated on latrine wastewater samples with natural sunlight on both sunny and cloudy days. The results showed the potential of sunlight-activated PMA pretreatment to be integrated into a lab-on-a-chip (LOAC) PCR device for off-the-grid microbial detection and quantification.

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Orejudos, William. « Search for scalar quarks at [square root of s=] 130-184 GeV with the ALEPH detector ». 1998. http://catalog.hathitrust.org/api/volumes/oclc/41249471.html.

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Thesis (Ph. D.)--University of Wisconsin--Madison, 1998.
Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 147-151).

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Moyers, Jr John Clifton. « A High Performance Detector Electronics System for Positron Tomography ». 1990. http://trace.tennessee.edu/utk_gradthes/13.

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Positron Emission Tomography (PET) has been a very useful laboratory tool for the noninvasive study of dynamic physiological processes within the human body. Its clinical worth in cardiology, neurology, and oncology has been verified for well over a decade. Only with the most recent introduction of high performance analog and VLSI digital components yielding higher scanner resolutions at reduced costs, has clinical PET truly become a reality. The High Performance Detector Electronics System presented here represents indubitably the most advanced processing system available in the clinical PET market.

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Fattal, Ann-Katrin. « Computer Vision for Distant Vehicle Detection : How to Find Region Proposals for Low-Resolution Objects ? » Phd thesis, 2020. https://tuprints.ulb.tu-darmstadt.de/11310/13/2019-10-30_Fattal_AnnKatrin.pdf.

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Safety is crucial to the development and acceptance of assisted and highly automated driving functions. In 2017, 69.3% of German fatal accidents happened on roads where the speed limit was not enforced or higher than 100km/h. At this speed, to perform safe driving maneuvers, the environment perception is a key element. Detecting objects in distances up to 200m is instrumental in anticipating potential obstacles. Due to hardware limitations, an automotive camera maps cars in e.g. 200m distance to an image of only 8px width. Hence, the absence of local details degrades the state-of-the-art detection methods designed for detecting bigger sized objects. The scope of this thesis is to develop, extend and evaluate object region localizers to improve the detection range of cameras. A saliency inspired voting map is proposed that highlights anomalies in automotive scenes. The environment is modeled with few homogeneous regions representing the background within the image. Such global features allow detecting small object regions. Inspired by the concept of learning features, this thesis presents machine learning methods detecting small objects. Existing labeled data sets such as the KITTI data set only have object regions which sizes are larger than 25px height. The presented methods in this thesis are performed against a newly created data set with 67% of object regions having a width of 8-30px, a range that has rarely been subject to research yet. Convolutional Neural Network based localizers have been evaluated and extended. To maintain a low computational power, only small networks can be used. However, such networks are limited to the usage of local features. An incorporation of global generic priors to local networks is proposed, which increases the recall especially for small object regions. The parameters to adjust Region Proposal Networks (RPNs) for the special case of small objects are further optimized and the main parameters are identified. A novel relevance based net-surgery is introduced, allowing to select the most relevant features while maintaining the recall of the RPN. It is then possible to reduce the network size to these few features.

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Peer, Fawzia Ismail. « A comparative study of the 14C-Urea Breath Test and histology for the detection of Helicobacter pylori in terms of cost effectiveness and patient acceptability ». Thesis, 2001. http://hdl.handle.net/10321/2797.

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Dissertation submitted in compliance with the requirements for the Masters Degree in Technology: Radiography, Technikon Natal, 2001.
The purpose of this study was to evaluate the Carbon-14 Urea Breath Test e4C-UBT) and histology for the detection of Helicobacter pylori (H pylori) in terms of cost-effectiveness and patient perceptions. It was hypothesized that the 14C_UBTwas more cost-effective and more easily tolerated than a histological analysis of a biopsy specimen obtained on endoscopy for H pylori detection
M

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