In this thesis, a computationally efficient method for detecting a whistle and capturing it using a 4 microphone array is proposed. Furthermore, methods are developed to efficiently process the data captured from all the microphones to estimate the direction of the sound source. The accuracy, the shortcoming and the constraints of the method proposed are also discussed. There is an emphasis placed on being computationally efficient so that the methods may be implemented on a low cost microcontroller and be used to provide a heading to an Unmanned Ground Vehicle. / MS / As humans, we rely on our sense of hearing to help us interact with the outside world. It helps us to listen not just to other people but also for sounds that maybe a warning for us. It can often be the first warning we get of an impending danger as we might hear a predator before we see it or we might hear a car brake and slip before we turn to look at it. However, it is not merely the ability to hear a sound that makes hearing so useful. It is the fact that we can tell which direction the sound is coming from that makes it so important. That is what allows us to know which direction to turn towards to respond to someone or from which direction the sound warning us of danger is coming. We may not be able to pinpoint the location of the source with complete accuracy but we can discern the general heading. It was this idea that inspired this research work. We wanted to be capable of estimating where a sound is coming from while being computationally efficient so that it may be implemented in real time with the help of a low cost microcontroller. This would then be used to provide a heading to an Unmanned Ground Vehicle while keeping the costs down.

The concept of replacing threads with flexible wires and sensors in a fabric to provide an underlying platform for integrating electronic components is known as e-textiles. This concept can be used to design applications involving different types of electronic components including sensors, digital signal processors, microcontrollers, color-changing fibers, and power sources. The adaptability of the textiles to the needs of the individual and the functionality of electronics can be integrated to provide unobtrusive, robust, and inexpensive clothing with novel features. This thesis focuses on the design of e-textiles for acoustic signal processing applications. This research examines challenges encountered when developing e-textile applications involving distributed arrays of microphones. A framework for designing such applications is presented. The design process and the performance analysis of two e-textiles, a large-scale beamforming fabric and a speech-processing vest, are presented. / Master of Science

Yes / Sonic Hedgehog (SHH) is a glycoprotein associated with development that is also expressed in the adult CNS and released after brain injury. Since the SHH receptors PTCH1 (patched homolog-1) and SMO (Smoothened) are highly expressed on astrocytes, we hypothesised that SHH regulates astrocyte function. Primary mouse cortical astrocytes derived from embryonic (E15) Swiss mouse cortices, were treated with two chemically distinct agonists of the SHH pathway, which caused astrocytes to elongate and proliferate. These changes are accompanied by decreases in the major astrocyte glutamate transporter, GLT-1 and the astrocyte intermediate filament protein GFAP. Multi-site electrophysiological recordings revealed that the SHH agonist, SAG supressed neuronal firing in astrocyte-neuron co-cultures and this was abolished by the astrocyte metabolic inhibitor ethylfluoroacetate, revealing that SHH stimulation of metabolically-active astrocytes influences neuronal firing. Using 3D co-culture, MAP2 western blotting and immunohistochemistry, we show that SHH-stimulated astrocytes protect neurons from kainate induced cell death. Altogether the results show that SHH regulation of astrocyte function represents an endogenous neuroprotective mechanism. / BBSRC

International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / Planar microstrip antennas are desirable in many telemetry applications because they are small in size, light in weight, and conformal to most surfaces. The design and optimization of circularly-polarized omnidirectional microstrip arrays using a new software simulation tool are discussed in this paper. Critical design issues such as the optimization of each array element for circular polarization and the minimization of mutual couplings as well as feed network mismatch are examined. The software tool, which consists of a novel graphical user interface and a full-wave numerical simulator for a flat mounting surface, provides a testbed environment for the user to explore new designs as well as optimizing existing designs. Using this tool, the design of several wraparound arrays with different mounting cylinder radii are presented. Comparisons between measured and simulated data for two S-band 8-element wraparound arrays are also presented.

Confocal microscopes utilize point illumination and pinhole detection to reject out-of-focus light. Because of the point illumination and detection pinhole, confocal microscopes typically utilize point scanning for imaging, which limits the overall acquisition speed. Due to the excellent optical sectioning capabilities of confocal microscopes, they are excellent tools for the study of three-dimensional objects at the microscopic scale. Fluorescence confocal microscopy is especially useful in biomedical imaging due to its high sensitivity and specificity. However, all designs for confocal microscopes must balance tradeoffs between the numerical aperture (NA), field of view (FOV), acquisition speed, and cost during the design process. In this dissertation, two different designs for an array confocal microscope are proposed to significantly increase the acquisition speed of confocal microscopes. An array confocal microscope scans an array of beams in the object plane to parallelize the confocal microscope to significantly reduce the acquisition time. If N beams are used in the array confocal microscope, the acquisition time is reduced by a factor of N. The first design scans an array of miniature objectives over the object plane to overcome the trade-off between FOV and NA. The array of objectives is laterally translated and each objective scans a small portion of the total FOV. Therefore, the number of objectives used in the array limits the FOV, and the FOV is increased without sacrificing NA. The second design utilizes a single objective with a high NA, large FOV, and large working distance designed specifically for whole brain imaging. This array confocal microscope is designed to speed up the acquisition time required for whole brain imaging. Utilizing an objective with a large FOV and scanning using multiple beams in the array significantly reduces the time required to image large three-dimensional volumes. Both array confocal microscope designs use beam-splitting gratings to efficiently split one laser beam into a number of equal energy outgoing beams, so this dissertation explores design methods and analyses of beam-splitting gratings to fabrication errors. In this dissertation, an optimization method to design single layer beam-splitting gratings with reduced sensitivity to fabrication errors is proposed. Beam-spitting gratings are typically only designed for a single wavelength, so achromatic beam-splitting grating doublets are also analyzed for possible use in array confocal microscopes with multiple excitation wavelengths. An analysis of the lateral shift between grating layers in the achromatic grating doublet proves grating profiles with constant first spatial derivatives are significantly less sensitive than continuous phase profiles. These achromatic grating doublets have designed performance at two wavelengths, but the diffraction angles at the two wavelengths differ. To overcome that limitation, scale-invariant achromatic gratings are designed, which not only provide designed performance at two wavelengths, but also equal diffraction angles at two wavelengths.

<p>In this thesis, we develop methods for addressing the deficiencies of array processing with linear thinned arrays. Our methods are designed for array systems mounted on moving platforms and exploit synthetic aperture processing techniques. In particular, we use array motion to decrease the sidelobe levels and increase the degrees of freedom available from thinned array systems. In this work, we consider two application areas 1) passive SONAR and 2) ultrasound imaging. </p><p>Synthetic aperture processing is a methodology for exploiting array motion and has been successfully used in practice to increase array resolution. By spatially sampling along the path of the array virtual sensors can be realized and coherently fused to the existing array. The novel contribution of this work is our application of synthetic aperture processing. Here our goal is not to increase array resolution, instead we propose to use the synthetic aperture process to expand the spatial covariance and spatial frequency sensing capabilities of thinned array system.</p><p> </p><p>In the passive sensing case, we use a class of thinned arrays know as co-prime linear sensor arrays for source localization. The class of co-prime arrays provides roughly half the aperture worth of spatial covariances and with modest array motion can be extended to the full aperture of the array. The amount of motion required to produce a full set of spatial covariances is shown to be a function of the co-prime array parameters and is only a fraction of the total aperture of the array. The full set of spatial covariances can be used to form a spatial covariance matrix with dimension equal to that of a uniform array. With a spatial covariance matrix in hand one can perform signal processing tasks as if the array were fully populated. Three methods for spatial covariance matrix estimation are compared in different source localization scenarios. In the work presented here, we demonstrate the benefits of our approach for achieving reduced sidelobe levels and extending the source localization capabilities above the limits of the static co-prime array. </p><p>In the active sensing case, we develop a framework for incorporating motion using thinned arrays for ultrasound imaging. In this setting, array motion is used to augment the spatial frequency sensing capabilities of the thinned array system. Here we develop an augmentation strategy based on using quarter-wavelength array translations to fill-in missing spatial frequencies not measured by the static thinned array. The quarter-wavelength translation enables the thinned array system to sample missing spatial frequencies and increase the redundancy of other spatial frequencies sampled by the array. We compare the level of redundancy in sampling the spatial frequencies achieved by the thinned arrays post translation to different levels of sample redundancy derived from pruning the transmit/receive events of a uniform array. In this manner, we are able to examine how the level of spatial frequency redundancy afforded by different thinned arrays compare over the full redundancy range of the uniform array. While artificially pruning the uniform array does not necessarily create realizable arrays, it provides the means to compare image quality at different spatial frequency redundancy levels. In this work, we are able to conclude that images formed from thinned arrays using the translated synthetic aperture process are capable of approximating images formed from the corresponding uniform array. In particular, the systems considered in this work have approximately one-third of the active sensors when compared to the uniform array. </p><p>In both application areas, the use of thinned arrays offers a reduction in the cost to deploy and maintain a given array system. The feature that makes it possible to overcome the spatial sampling deficiencies of thinned array systems is motion and it is at the core of the performance gains in these applications.</p> / Dissertation

Le cancer de la prostate (CaP) est actuellement le cancer le plus fréquent en France et constitue l'une des principales causes de décès par cancer chez l'homme dans les pays industrialisés. Un tiers des patients avec un CaP à priori localisé auront déjà des micro-métastases au moment du traitement local. Ces patients qui répondent dans un premier temps à la castration (hormonothérapie) seront cependant en échappement hormonal dans les 2 ans qui suivent. Récemment, plusieurs essais cliniques de phase III ont rapporté un gain de survie avec la chimiothérapie à base de docétaxel dans les CaPs métastatiques résistants à la castration. Néanmoins, la survie n'est prolongée que de 2 ou 3 mois et de nouvelles approches thérapeutiques ciblant des voies de signalisation spécifiques sont donc nécessaires. Les travaux réalisés au cours de cette Thèse ont permis tout d'abord de montrer, grâce à l'utilisation de TMAs, que la surexpression de TP53INP1, une protéine de réponse au stress, était un facteur de mauvais pronostic dans le CaP, prédictif notamment du risque de rechute biologique. Nous avons ensuite pu montrer grâce à des xénogreffes de cellules tumorales (LNCaP) que les taux d'ARNm de TP53INP1 diminuaient durant l'hormonothérapie et que TP53INP1 était de nouveau significativement surexprimée dans les tumeurs résistantes à la castration. Nous avons développé et déposé un brevet pour un oligonucléotide antisens (ASO) inhibant TP53INP1. Le traitement in vitro des lignées cellulaires hormonosensibles LNcaP et hormono-résistantes C4-2 par l'ASO induit une diminution d'expression de la protéine TP53INP1, inhibe la prolifération cellulaire et induit une augmentation de l'apoptose. / Prostate cancer (PC) is the most common malignancy in France and one of the most frequent leading causes of cancer-related death in men in industrialized countries. Even with aggressive screening, approximately one-third of patients believed to have localized PC will already have micro-metastatic disease at the time of definitive local therapy. These patients initially respond to androgen ablative therapy, but with time, their tumors ultimately become unresponsive and recur within 2 years as castration-resistant prostate cancer (CRPC). Recently, docetaxel-based regimens have shown improved survival in men with CRPC in phase III studies. However, the median overall survival was prolonged for only 2-3 months, and thus development of new therapeutic approaches that target relevant signaling pathways are essential to restore the androgen-sensitivity of CRPC. We showed, using tissue micro-array (TMA) analysis, that over-expression of Tumor Protein 53-Induced Nuclear Protein 1 (TP53INP1), a cell stress response protein, is a worse prognostic factor in PC, particularly predictive of biological cancer relapse. We also we found that TP53INP1 protein expression decreases during castration therapy (CT) and significantly increases in human CRPC. TP53INP1 mRNA was also significantly increased in castration-resistant (CR) tumors of LNCaP xenograft compared to the castration-sensitive (CS) taken before CT. We developed and world-wide patented one antisense oligonucleotide (ASO) targeting TP53INP1 (PCT/IB2011/054555). Treatment of LNCaP and C4-2 cells in vitro with TP53INP1 ASO downregulates TP53INP1 protein level, inhibits proliferation and induces apoptosis.

>Magister Scientiae - MSc / Future radio surveys as the Square Kilometer Array (SKA) and its precursor, the "Meer" Karoo Array Telescope (MeerKAT), will map the Neutral Hydrogen (HI) in large areas of the sky using the intensity mapping (IM). HI IM is currently one of the most promising ways of accessing the Large-Scale Structure of the Universe. The distribution of matter in the Universe not only encodes its composition but also how it evolves and its initial conditions. An effect on the matter distribution that will be detected by the SKA on the post re-ionization Universe are the Baryonic Acoustic Oscillations (BAO). While it has been shown that in single dish mode the SKA can measure the BAO peak in the radial 21cm power spectrum at low redshifts, this possibility has not yet been studied in detail for the MeerKAT. In this thesis we construct a set of full sky simulations to test how well MeerKAT will be able to extract the BAO wiggles along the line of sight. These simulations are done for the frequencies corresponding to MeerKAT L-band. The maps combine the cosmological HI signal, systematic noise, cosmological foregrounds and the instrumental telescope beam. A model-independent estimator is used to extract the BAO wiggles by subtracting a smooth polynomial component from the 21cm radial power spectrum. We test with simulations if this estimator is biased and the signal to noise of the extraction. We conclude that we are able to remove contaminants and recover the cosmological HI signal while not risking the recovery of the BAO signal. We investigate the effects of varying the sky area and the observational hours on the signal to noise ratio for the BAO wiggles. We found that for a HI IM experiment using MeerKAT, the optimal sky area to detect the BAO along the line of sight is 50% of the sky. With a signal-to-noise ratio of 3.37. This can be achieved with 2000 hours of exposure time

Gegenstand der Arbeit stellt eine erstmalig unternommene, architekturübergreifende Studie über feldprogrammierbare Logikbausteine zur Implementierung synchroner Schaltkreise dar. Zunächst wird ein Modell für allgemeine feldprogrammiebare Architekturen basierend auf periodischen Graphen definiert. Schließlich werden Bewertungsmaße für Architekturen und Schaltkreislayouts angegeben zur Charakterisierung struktureller Eigenschaften hinsichtlich des Verhaltens in Chipflächenverbrauch und Signalverzögerung. Ferner wird ein generisches Layout-Werkzeug entwickelt, das für beliebige Architekturen und Schaltkreise Implementierungen berechnen und bewerten kann. Abschließend werden neun ressourcenminimalistische Architekturen mit Maschen- und mit Inselstruktur einander gegenübergestellt. / This work presents a first architecture-spreading study on field-programmable logical devices leaving the beaten tracks of commercial architecture improvements. After a formal model for general field-programmable architectures based on periodic graphs has been given, some feasible evaluation metrics for architectures and circuit layouts are defined characterizing structural properties of architectures in respect of chip area usage and performance. Then, a generic layout tool is developped working on arbitrary architecures and circuits. Finally, nine resource minimal mesh- and island-style architectures are compared.

A translocação recíproca é o rearranjo equilibrado mais comum em humanos. Frequentemente, indivíduos com rearranjos equilibrados não apresentam manifestações clínicas, entretanto, na meiose, o pareamento entre cromossomos translocados forma uma figura quadrivalente em forma de cruz que torna a disjunção cromossômica incerta e dependendo do rearranjo, o individuo pode vir a ser infértil, apresentar um risco aumentado de abortamento espontâneo e/ou da prole apresentar alterações fenotípicas. Neste projeto, investigamos duas famílias de pacientes inférteis, portadores de translocações cromossômicas. O objetivo foi caracterizar as alterações citogenéticas e citogenômicas relacionadas à infertilidade masculina em pacientes portadores de rearranjos aparentemente equilibrados, associando técnicas de citogenética clássica (bandeamento GTG), citogenética molecular (FISH) e citogenômica (array-CGH). Foram estudados sete indivíduos da família 1, sendo diagnosticados três portadores da translocação (X;22), sendo um deles azoospérmico. Nesta família foram ainda detectados dois casos de mosaicismo para síndrome de Turner. A família 2 foi composta por dois irmãos oligozoospérmicos, portadores de translocação (8;13). Com a aplicação da técnica de FISH, definimos o cariótipo final dos portadores dos rearranjos como 46,XX ou 46,XY,t(X;22)(p22.3;q11.2) para a família 1 e 46,XY,t(8;13)(q13;q14)para a família 2. A técnica de array-CGH (plataforma 2x400K, Agilent) detectou alterações no número de cópias de alguns genes candidatos relacionados ao fenótipo de infertilidade, sendo a sequência 132 de piRNAs, os genes DDX11, Jagged 2 e ADAM18 na família 1 e os genes candidatos ADAM18 e POTE nos pacientes da família 2. / Reciprocal translocations are the most common balanced rearrangement in humans. Often individuals with balanced rearrangements show no clinical findings. However, in meiosis, the pairing between translocated chromosomes forms a quadrivalent cross-shaped figure which has the effect of making chromosome disjunction uncertain and, depending on the rearrangement, and on the segregation of the unbalanced chromosomes, the individual can be infertile, can present with an increased risk of spontaneous abortions or can have an offspring with abnormal phenotype. We have studied two families of infertile patients, who were carriers of chromosomal translocations. The objective was to characterize the cytogenetic and cytogenomic alterations related to male infertility in patients with apparently balanced rearrangements using classical cytogenetic techniques (GTG banding), molecular cytogenetics (FISH) and cytogenomics (array-CGH). Seven subjects of the family 1 were studied, including three carriers of translocation (X;22), one azoospermic. Two cases of mosaicism for Turner syndrome were detected in this family. The second family consisted of two oligozoospermic brothers with translocation (8;13). FISH was used to characterize the karyotypes as 46, XX or 46,XY, t(X;22)(p22.3;q11.2) for the members of the family 1 and 46,XY,t(8;13)(q13;q14) for family 2. Array-CGH was also performed using the Agilent platform 2x400K, to detect associated copy number variations of some of the candidate genes that could be related to infertility. In the family 1 the candidate genes were 132 piRNAs sequences and DDX11,Jagged 2 and ADAM18 genes. The candidate genes for the family 2 were ADAM18 and POT.