Thesis (M.App.Sc.) - Carleton University, 2002. / Includes bibliographical references (p. 93-95). Also available in electronic format on the Internet.

We consider the distributed detection of an emitter using multiple sensors deployed at deterministic locations. The signal from the emitter follows a signal attenuation model dependent on the distance between the sensor and the emitter. The sensors transmit their decisions to the fusion center through a parallel access Binary Symmetric Channel (BSC) with a cross-over probability. We seek to optimize the detection performance under a prescribed false alarm at the sensor level and at the system level. We consider the triangular topology structure and using the least favorable emitter range study the impact of the BSC on the system level detection fusion rules. The MAJORITY fusion rule is found to be optimal under certain conditions.

L’efficacité d’une radioimmunothérapie (RIT) peut impliquer la coexistence des effets ciblés et des effets dit « non ciblés ». Les effets ciblés regroupent les effets biologiques observés dans les cellules ou tissus traversés par les particules ionisantes alors que les effets non-ciblés (ou bystander) sont observés dans des cellules qui n’ont pas été irradiées mais qui sont au proche voisinage des cellules exposées. Nous avons au cours de cette étude évalué in vitro et in vivo, la contribution des effets ciblés et non ciblés dans l’efficacité obtenue lors de la RIT alpha (212Pb, 213Bi) et de la RIT Auger (125I). Les effets ciblés ont été mesurés in vitro sur les cellules irradiées (cellules donneuses) alors que les effets bystander sont mesurés sur les cellules non irradiées (cellules receveuses) par une méthode de transfert de milieu. Elle consiste, à traiter les cellules receveuses dans un milieu de culture pré-incubé pendant 2h avec les cellules donneuses. Nos résultats montrent que la contribution des effets ciblés est nettement plus importante qu’en RIT alpha qu’Auger. En RIT alpha, on observe que les lésions de l’ADN (foci 53BP1et γ-H2AX) pourraient être différenciées en lésions complexes (sites multilésés = observation de gros foci) ou simples lésions (petit foci). Par contre en RIT Auger, ce sont les effets non ciblés qui prédominent sur les effets ciblés. L’utilisation d’inhibiteurs pharmacologiques des ROS montre l’implication du stress oxydatif dans ces effets non ciblés observés en RIT alpha et Auger. Ces effets non ciblés ont été observés également in vivo sur des souris athymiques porteuses de carcinoses péritonéales de petites tailles ; démontrant ainsi leur contribution dans l’efficacité thérapeutique finale observée après la RIT alpha et Auger. L’ensemble de ces résultats indiquent que même si des lésions de l’ADN sont produites après irradiation, que les effets non ciblés pourraient aussi contribuer à l’efficacité thérapeutique finale observée avec les anticorps couplés aux émetteurs de particules alpha ou d’électrons Auger. Ces résultats sont particulièrement intéressants pour la thérapie ciblée car les vecteurs utilisés n’ont pas souvent accès à l’ensemble des cellules constituant la tumeur. / We investigated in vitro and in vivo the relative contribution of targeted and non-targeted effects in the therapeutic efficacy against tumors of antibodies radiolabeled with alpha particle (212Pb, 213Bi) or Auger electron (125I) emitters. Targeted effects occurs in cells directly crossed by ionising particles while non-targeted effects are measured in cells neighbouring irradiated cells. Targeted effects were measured in vitro in cells exposed to antibodies radiolabeled with alpha or Auger emitters (donor cells) while non-targeted effects were investigated in recipient cells. Recipient cells consisted of cells not exposed to radiolabeled-mAbs, but grown in medium previously incubated for 2h with donor cells. We showed that the relative contribution of targeted effects versus non-targeted effects was higher during alpha RIT than Auger RIT. Alpha particles produced 53BP1 and gamma-H2AX foci in donor cells that could be differentiated in large, medium and small foci, while only small foci were observed in recipient cells. We assumed that large foci would correspond to locally multiply damage sites in DNA. Conversely, Auger RIT led predominantly to non-targeted effects compared with targeted effects. Use of radical scavengers showed that oxidative stress was involved in non-targeted effects. In vivo, we showed in athymic nude mice bearing tumor xenograft that non-targeted effects were also involved and participated to therapeutic efficacy of radiolabeled antibodies. These results indicate that although producing single DNA lesion, non-targeted effects can contribute to the therapeutic efficacy of mAbs radiolabeled with alpha particle or Auger electron emitters. These findings are particularly relevant for targeted therapy in which vectors cannot gain access to every tumor cell.

In dieser Arbeit wurde ein Sensorkonzept mit Hilfe der Si-basierten Lichtemitter (MOSLED) zum Östrogennachweis in wässrigen Lösungen entwickelt. Das Sensorkonzept basiert auf einer direkten Fluoreszenzanalyse und besteht aus der Anordnung der Bio-Komponenten und dem Verfahren zu ihrer Herstellung sowie dem eigentlichen Meßverfahren. Die Anordnung besteht aus drei Teilen: die Funktionalisierung der MOSLED-Oberfläche, die Immobilisierung des hER -Rezeptors und die Herstellung der Referenzlösung. Den Schwerpunkt dieser Arbeit bildet die Ausführung dieser drei Teile. Die Funktionalisierung der SiO2-Oberfläche der MOSLED wurde mit Hilfe eines im Rahmen dieser Arbeit entwickelten SSC (Spraying Spin Coating)- Verfahrens realisiert. Die Ausgangsmaterialien dieses Verfahrens sind organofunktionelle Silangruppen mit drei unterschiedlichen funktionellen Gruppen, nämlich die Amino-, Carboxyl- und die Thiolgruppen. Die Optimierung dieser Methode erfolgte mittels der zwei Silangruppen APMS ((3- Aminopropyl)trimethoxysilane und Triamino-APMS (N-[3-(Trimethoxysilyl)propyl]ethylenediamine mit der gleichen Molekülstruktur, aber mit einer unterschiedlichen Anzahl an funktionellen Gruppen. Diese Resultate wurden mit in der Literatur beschriebenen Verfahren verglichen. Die Optimierung der SSC-Methode wurde zuerst auf einfache SiO2-Oberflächen und dann auf der Oberfläche der MOSLED angewendet. Die Proben wurden mit Hilfe üblicher Methoden der Oberflächenphysik- wie FTIR-, Raman- und XPS-Spektroskopie untersucht.Die Oberflächenrauhigkeit wurde mittels AFM-Spektroskopie ermittelt, deren Aufnahmen eine glatte Oberfläche bei den mit der SSC-Methode silanisierten Proben zeigen. Während die Hydrophobizität der funktionalisierten SiO2-Oberflächen zunimmt, sinkt dabei die Oberflächenenergie, welche die Anbindung eines hER -Rezeptors mit großer Bindungsenergie begünstigt. Zur Immobilisierung des hER -Rezeptors wurde dieser erst an das Hüllenmolekül des QDots R-655-Farbstoffs gebunden und anschließend an der SSC-silanisierten SiO2-Oberflächen adsorbiert. Der Anteil der immobilisierten Rezeptoren wurde mittels PL-Messung kontrolliert. Eine andere Immobilisierungstrategie des hER -Rezeptors an die SiO2-Oberfläche kann mit Hilfe eines Aminosäure-Derivates um den Rezeptor realisiert werden. Eine Adsorption der Lysinaminosäure an die SSC-APMS silanisierten SiO2- Oberflächen als Funktion des pH-Wertes wurde durchgeführt, und der Adsorbatsanteil des Lysins mittels XPS-Messung durch die Bindungsenergien der Energieniveaus C1s und N1s berechnet. Eine Referenzlösung mit QDots R 800-Farbstoff markierten Östrogenmolekülen kommt zum Einsatz. Dabei wird die Position 17 des β-Estradiolmoleküls, welches mit einem N-Hydroxysuccinimide Derivat versehen ist, an das Hüllenmolekül des QDots R 800-Farbstoff gebunden,sodass der Phenolring des β-Estradiols frei bleibt. Insbesondere ist bei den FTIR-Spektren eine nichtgebunden OH-Gruppe des β-Estradiolmoleküls gut erkennbar. Das gesamte Sensorkonzept wurde an zwei mit Östrogen mit einer Konzentration von 1mM und 1μM versetzten Wasserproben getestet. Die Anordnung der Bio-Komponenten wurde mittels PL nachgewiesen. Der Östrogennachweis wurde mit Hilfe des Ge- und Tb-basierten Lichtemitters demonstriert.

No description available.

In this thesis the fabrication and analytical evaluation of two new electrospray emitters utilized for mass spectrometry analysis is presented. The emitters are based on a new concept, where the spray orifice can be varied in size. The thesis is based on two papers. All present-day nanoelectrospray emitters have fixed dimensions. The range of the applicable flow rate for such an emitter is therefore rather limited and exchange of emitters may be necessary from one experiment to another. Optimization of the signal of the analyte ions is also limited to adjustments of the applied voltage or the distance between the emitter and the mass spectrometer inlet. Furthermore, clogging can occur in emitters with fixed dimensions of narrow orifice sizes. In this thesis, electrospray emitters with a variable size of the spray orifice are proposed. An open gap between two thin substrates is filled with sample solution via a liquid bridge from a capillary. Electrospray is generated at the end point of the gap, which can be varied in width. In Paper I, electrospray emitters fabricated in polyethylene terephthalate have been evaluated. Triangular tips are manually cut from the polymer film. The tips are mounted to form a gap between the edges of the tips. The gap wall surfaces are subjected to a hydrophilic surface treatment to increase the wetting of the gap walls. In Paper II, silicon electrospray chips with high precision are fabricated and evaluated. A thin beam, elevated from the bulk silicon chip is fabricated by means of deep reactive ion etching. The top surfaces of the beams of two chips act as a sample conduit when mounted in the electrospray setup. An anisotropic etching step with KOH of the intersecting <100> crystal planes results in a very sharp spray point. The emitters were given a hydrophobic surface treatment except for the hydrophilic gap walls. For both emitter designs, the gap width has been adjusted during the experiments without any interruption of the electrospray. For a continuously applied peptide mixture, a shift towards higher charge states and increased signal to noise ratios could be observed when decreasing the gap width. The limit of detection has been investigated and the silicon chips have been interfaced with capillary electrophoresis. / QC 20101108

The tremendous ongoing growth of wireless digital communications has raised spectrum shortage and security issues. In particular, the need for new spectrum is the main obstacle in continuing this growth. Recent studies on radio spectrum usage have shown that pre-allocation of spectrum bands to specific wireless communication applications leads to poor utilization of those allocated bands. Therefore, research into new techniques for efficient spectrum utilization is being aggressively pursued by academia, industry, and government. Such research efforts have given birth to two concepts: Cognitive Radio (CR) and Dynamic Spectrum Access (DSA) network. CR is believed to be the key enabling technology for DSA network implementation. CR based DSA (cDSA) networks utilizes white spectrum for its operational frequency bands. White spectrum is the set of frequency bands which are unoccupied temporarily by the users having first rights to the spectrum (called primary users). The main goal of cDSA networks is to access of white spectrum. For proper access, CR nodes must identify the right cDSA network and the absence of primary users before initiating radio transmission. To solve the cDSA network access problem, methods are proposed to design unique second-order cyclic features using Orthogonal Frequency Division Multiplexing (OFDM) pilots. By generating distinct OFDM pilot patterns and measuring spectral correlation characteristics of the cyclostationary OFDM signal, CR nodes can detect and uniquely identify cDSA networks. For this purpose, the second-order cyclic features of OFDM pilots are investigated analytically and through computer simulation. Based on analysis results, a general formula for estimating the dominant cycle frequencies is developed. This general formula is used extensively in cDSA network identification and OFDM signal detection, as well as pilot pattern estimation. CR spectrum awareness capability can be enhanced when it can classify the modulation type of incoming signals at low and varying signal-to-noise ratio. Signal classification allows CR to select a suitable demodulation process at the receiver and to establish a communication link. For this purpose, a threshold-based technique is proposed which utilizes cycle-frequency domain profile for signal detection and feature extraction. Hidden Markov Models (HMMs) are proposed for the signal classifier. The spectrum awareness capability of CR can be undermined by spoofing radio nodes. Automatic identification of malicious or malfunctioning radio signal transmitters is a major concern for CR information assurance. To minimize the threat from spoofing radio devices, radio signal fingerprinting using second-order cyclic features is proposed as an approach for Specific Emitter Identification (SEI). The feasibility of this approach is demonstrated through the identification of IEEE 802.11a/g OFDM signals from different Wireless Local Area Network (WLAN) card manufactures using HMMs. / Ph. D.

Der Vortrag zeigt die Komplexität der Wechselwirkungen zwischen Infrarotstrahler und Werkstoff beim Infrarotschweißen von Kunststoffen auf. Hierfür werden die Haupteinflüsse auf die Strahler-Werkstoff-Wechselwirkungen beschrieben. Diese sind das Emissionsverhalten des Infrarotstrahlers und das Absorptionsverhalten des Kunststoffs. Der Einfluss der Infrarotstrahlerart (Quarzglasstrahler, Metallfolienstrahler) und von Füllstoffen (Ruß, Glasfasern) im Kunststoff wird näher betrachtet. Zudem enthält der Vortrag eine Empfehlung für die Vorgehensweise beim Infrarotschweißen von Kunststoffen, die Vor- und Nachteile des Fügeverfahrens und einen Einblick in aktuelle Forschungsaktivitäten auf dem Gebiet des Infrarotschweißens von Kunststoffen.

Submitted by PPG Engenharia e Tecnologia de Materiais (engenharia.pg.materiais@pucrs.br) on 2018-04-24T14:42:28Z No. of bitstreams: 1 Dissertacao Taila Final.pdf: 2384346 bytes, checksum: 8e3d52f21033cdc04d8f1c3449453ceb (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-05-08T19:50:29Z (GMT) No. of bitstreams: 1 Dissertacao Taila Final.pdf: 2384346 bytes, checksum: 8e3d52f21033cdc04d8f1c3449453ceb (MD5) / Made available in DSpace on 2018-05-08T20:07:12Z (GMT). No. of bitstreams: 1 Dissertacao Taila Final.pdf: 2384346 bytes, checksum: 8e3d52f21033cdc04d8f1c3449453ceb (MD5) Previous issue date: 2018-02-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The solar cells manufactured in n-type silicon, doped with phosphorus, do not present light induced degradation and they have the potential of achieving high efficiency due to the larger minority charge carrier lifetime. Besides, they are less susceptible to contamination by metal impurities. The aim of this work was to analyze different dopants to obtain the p+ region in n+np+ solar cells manufactured in Czochralski silicon wafers, solar grade, n-type, 120 ?m thick. The acceptor impurities used were B, Al, Ga, GaB and AlGa, deposited by spin-on and diffused at high temperature. The temperature, time and gases used in the process of diffusion were ranged. The sheet resistances (R?) of the diffused regions and the impurity concentration profiles were measured. We concluded that the B and GaB can be diffused at 970? C for 20 min to obtain p+ emitters with values of R? suitable to the production of solar cells with screenprinted metal grid. The Ga and AlGa require high temperatures (greater than 1100? C) and long times to produce doping profiles compatible with the production of solar cells. The Al did not produce low sheet resistance regions, even at temperatures of 1100? C. The use of argon gas instead of the nitrogen did not lead to the decreasing of the sheet resistance. The GaB is the only one doping material analyzed that can be a viable replacement for the B in the production of p+ emitter in n-type solar cells.The GaB was the only one doping material analyzed that allowed the manufacture of solar cells with the maximum efficiency of 13.5%, with the diffusion performed at 1020? C for 20 min. The FF was the main parameter that reduced the efficiency of solar cells doped with GaB when compared to the boron doped cells due to a lower shunt resistance. The n+np+ solar cell, 120 ?m thick, that achieved the highest efficiency was doped with boron and reached 14.9%, a value higher than the previously obtained in studies in the NT-Solar with thin silicon wafers. / As c?lulas solares fabricadas em l?minas de sil?cio tipo n, dopadas com f?sforo, n?o apresentam degrada??o por ilumina??o e t?m potencial de obten??o de maior efici?ncia devido ao maior valor do tempo de vida dos portadores de carga minorit?rios. Adicionalmente, s?o menos suscept?veis ? contamina??o por impurezas met?licas. O objetivo deste trabalho foi realizar uma an?lise de diferentes dopantes para obten??o da regi?o p+ em c?lulas solares n+np+fabricadas em l?minas de sil?cio Czochralski, grau solar, tipo n, com espessura de 120 ?m. Os elementos aceitadores utilizados foram o B, Al, Ga, GaB e AlGa, depositados por spin-on e difundidos em alta temperatura. Foram variadas as temperaturas, os tempos e os gases utilizados no processo de difus?o. Foi medida a resist?ncia de folha (R?) das regi?es difundidas e o perfil de concentra??o de impurezas em fun??o da profundidade. Foram desenvolvidas c?lulas solares com B, Ga, GaB e Al. Verificou-se que o B e GaB podem ser difundidos em temperatura de 970 ?C e por 20 min para obten??o de emissores com valores de R? compat?veis com a produ??o de c?lulas solares metalizadas por serigrafia. O Ga e AlGa necessitam de altas temperaturas (maiores que 1100 ?C) e tempos elevados para produzir perfis de dopantes compat?veis. O Al n?o produziu regi?es p+ de baixa R?, mesmo com a difus?o a 1100 ?C. O uso de Ar para substituir o N2 n?o acarretou em diminui??o da resist?ncia de folha. O GaB foi o ?nico dopante analisado que permitiu a fabrica??o de c?lulas solares com efici?ncia m?xima de 13,5 %, com difus?o a 1020 ?C por 20 min. O fator de forma foi o principal par?metro que reduziu a efici?ncia dos dispositivos com GaB quando comparado ao valor obtido com B devido a menor resist?ncia em paralelo. A c?lula solar n+np+ de 120 ?m de maior efici?ncia produzida neste trabalho foi dopada com boro e atingiu a efici?ncia de 14,9 %, sendo maior que as anteriormente obtidas em trabalhos realizados no NT-Solar com l?minas finas.

Les boites quantiques de semiconducteurs représentent une voie attractive pour la réalisation de sources de photon efficaces pour le transfert quantique de l’information, avec un fort potentiel de miniaturisation et d’intégration. Dans ce travail, les paires de photons intriqués sont générées via le déclin radiatif de bi-excitons, à partir de boite quantiques d’InAs auto-assemblées placé dans une jonction p-i-n. Dans une première série d’expérience d’interférence à deux photons, nous avons démontré des corrélations de polarisation non classiques et la capacité de deux photons à interférer. L’intrication a été démontrée avec une fidélité de 0.87±0.04, et une visibilité des interférences de 0.60±0.05. Nous avons ensuite réalisé le premier téléporteur injecté électriquement dans un circuit à fibre monomode. Une fidélité moyenne de 0.704±0.016 a été mesurée pour 6 états distribués symétriquement sur la sphère de Poincaré, ce qui supérieur à la limite classique de 2/3 et prouve la téléportation. Un dispositif modifié de téléportation permettant d’injecter des photons à partir d’un laser continu indépendant a été développé. L’interférence à deux photons entre sources différentes a été démontrée et des battements quantiques observés. La téléportation quantique des états de polarisation portés par les photons a été obtenue avec une fidélité moyenne 0.76±0.012. Le contrôle du spin des charges confinés dans les nanostructures tels que les boites quantiques requiert une compréhension profonde de la physique des matériaux constituant, y compris au niveau nucléaire. Ainsi, nous avons démontré le contrôle électrique de l’interaction hyperfine entre les spins électroniques et nucléaires en utilisant un composant à charge ajustable. La modélisation suggère que le mécanisme est contrôlé par le temps de corrélation hyperfine de l’électron et le temps de dépolarisation du noyau. / Semiconductor quantum dots offer an attractive route towards efficient and high-quality photon sources for optical quantum information applications, with potential for miniaturization and integration on chip. Here, entangled photon pairs are generated in the biexcitonic radiative cascade resulting from electrical excitation of InAs self-assembled quantum dots placed in a p-i-n diode. In a first set of experiments the non-classical polarisation correlations and the ability to interfere the photons in two-photon interference experiments was verified, finding entanglement fidelities of up to 0.87±0.04 and interference visibilities up to 0.60±0.05. Encouraged by the two-photon interference experiments, the first directly electrically driven teleporter was implemented in a single-mode fibre circuit. An average fidelity of 0.704±0.016 was achieved for six states symmetrically distributed on the Poincaré sphere, beating the classical limit of 2/3 and proving that quantum teleportation is taking place. A modified teleportation setup allowed for the accommodation of input photons from an independent CW laser. Two-photon interference between the dissimilar light sources was demonstrated and quantum beats could be observed. Quantum teleportation of polarisation states carried by laser photons was then performed with average fidelity 0.76±0.012. Controlling confined charge carriers in nano-scale systems such as quantum dots requires a deep understanding of the underlying material physics, even on the nuclear level. Voltage control of electron-nuclear hyperfine spin interactions was demonstrated using a charge-tuneable device. Modelling suggests that the mechanism is controlled mainly via the electron hyperfine correlation time and the nuclear depolarisation time.