A common problem in existing Search And Rescue (SAR) systems is that they must be activated by the missing person in order to work. This requires an awareness of the the risk of becoming distressed, which in many cases is not feasible. Furthermore, most of the localization systems require specialized hardware.In this thesis, the victim is assumed to wear a cellphone that could be located using readily available consumer electronics. A method of estimating the position of a transmitter, given radio signal measurements at different locations, is developed and verified with real and simulated data. A proof-of-concept system is built in which several users can jointly collect received signal strength data at different locations using mobile phones. The system analyzes the data in real-time and guides the users in the search by estimating the origin of the signal.An outdoor field test is conducted in which the searchers using the system are able to locate the hidden target phone without prior knowledge regarding the position. We are able to localize the victim with an accuracy of 10-20 meters in a timely manner using android smartphones. This shows the potential of a similar system in \abbrSAR scenarios. However, more work is needed to make the system viable in real scenarios and to remove some of the delimitations of the current implementation.

Afin de réduire l'intervalle de temps nécessaire entre la publication de l'information sur le Web et sa consultation par les utilisateurs, les sites Web reposent sur le principe de la Syndication Web. Les fournisseurs d'information diffusent les nouvelles informations à travers des flux RSS auxquels les utilisateurs intéressés peuvent s'abonner. L'objectif de la thèse est de proposer un système de notification passant à l'échelle du Web, prenant en considération le grand nombre d'utilisateurs et le débit élevé d'items. Nous proposons un index basé sur les mots-clés des requêtes utilisateurs permettant de retrouver ceux-ci dans les items des flux. Trois structures d'indexation de souscriptions sont présentées. Un modèle analytique pour estimer le temps de traitement et l'espace mémoire de chaque structure est détaillé. Nous menons une étude expérimentale approfondie de l'impact de plusieurs paramètres sur ces structures. Pour les souscriptions jamais notifiées, nous adaptons les index étudiés pour prendre en considération leur satisfaction partielle. Afin de réduire le nombre d'items reçus par l'utilisateur, nous intégrons une deuxième phase de filtrage par nouveauté et diversité considérant l'ensemble d'items déjà reçus par l'utilisateur.

Thesis (M.S.)--Pace University, 2006. / Includes bibliographical references.

abstract: V(D)J recombination is responsible for generating an enormous repertoire of immunoglobulins and T cell receptors, therefore it is a centerpiece to the formation of the adaptive immune system. The V(D)J recombination process proceeds through two steps, site-specific cleavage at RSS (Recombination Signal Sequence) site mediated by the RAG recombinase (RAG1/2) and the subsequent imprecise resolution of the DNA ends, which is carried out by the ubiquitous non-homologous end joining pathway (NHEJ). The V(D)J recombination reaction is obliged to be tightly controlled under all circumstances, as it involves generations of DNA double strand breaks, which are considered the most dangerous lesion to a cell. Multifaceted regulatory mechanisms have been evolved to create great diversity of the antigen receptor repertoire while ensuring genome stability. The RAG-mediated cleavage reaction is stringently regulated at both the pre-cleavage stage and the post-cleavage stage. Specifically, RAG1/2 first forms a pre-cleavage complex assembled at the boarder of RSS and coding flank, which ensures the appropriate DNA targeting. Subsequently, this complex initiates site-specific cleavage, generating two types of double stranded DNA breaks, hairpin-ended coding ends (HP-CEs) and blunt signal ends (SEs). After the cleavage, RAG1/2 proteins bind and retain the recombination ends to form post-cleavage complexes (PCC), which collaborates with the NHEJ machinery for appropriate transfer of recombination ends to NHEJ for proper end resolution. However, little is known about the molecular basis of this collaboration, partly attributed to the lack of sensitive assays to reveal the interaction of PCC with HP-CEs. Here, for the first time, by using two complementary fluorescence-based techniques, fluorescence anisotropy and fluorescence resonance energy transfer (FRET), I managed to monitor the RAG1/2-catalyzed cleavage reaction in real time, from the pre-cleavage to the post-cleavage stages. By examining the dynamic fluorescence changes during the RAG-mediated cleavage reactions, and by manipulating the reaction conditions, I was able to characterize some fundamental properties of RAG-DNA interactions before and after cleavage. Firstly, Mg2+, known as a physiological cofactor at the excision step, also promotes the HP-CEs retention in the RAG complex after cleavage. Secondly, the structure of pre-cleavage complex may affect the subsequent collaborations with NHEJ for end resolution. Thirdly, the non-core region of RAG2 may have differential influences on the PCC retention of HP-CEs and SEs. Furthermore, I also provide the first evidence of RAG1-mediated regulation of RAG2. Our study provides important insights into the multilayered regulatory mechanisms, in modulating recombination events in developing lymphocytes and paves the way for possible development of detection and diagnotic markers for defective recombination events that are often associated immunodeficiency and/or lymphoid malignancy. / Dissertation/Thesis / Ph.D. Molecular and Cellular Biology 2012

Data communication over cellular networks is expensive for the mobile device in terms of energy, especially when the received signal strength (RSS) is low. The mobile device needs to amplify its transmission power to compensate for noise leading to an increased energy consumption. This thesis focuses on developing a RSS map for the third generation cellular technology (3G) which can be stored locally at the mobile device, and can be used for avoiding expensive communication in low RSS areas. The proposed signal map is created by crowdsourced information collected from several mobile devices. An application is used to collect data in the mobile device of the user and the application periodically sends the information back to the server which computes the total signal map. The signal map is composed of three levels of information: RSS information, data rate tests and estimated energy levels. The energy level categorizes the energy consumption of an area into "High", "Medium" or "Low" based on the RSS, data rate test information and an energy model developed from physical power measurements. The coarse categorization provides an estimation of the energy consumption at each location. It is evaluated by collecting data traces on a smartphone at different locations and comparing the measured energy consumption at each location to the energy level categories of the map. The RSS prediction is preliminarily evaluated by collecting new data along a path and comparing how well it correlates to the signal map. The evaluation in this thesis shows that with the current collected data there are not enough observations in the map to properly estimate the RSS. However, we believe that with more observations a more accurate evaluation could be done.

La sindicación de contenidos en la Web permite la generación y distribución de contenidos a través de canales de información tales como blogs, medios de prensa o comunidades digitales. En la Web actual existen millones de estos canales, los cuales producen un flujo continuo de información actualizada: artículos de texto, fotografías, vídeos, etc. Los canales constantemente publican resúmenes de contenido en la forma de archivos de metadatos RSS o Atom, que son recolectados por agregadores de Internet o directamente por los consumidores finales. En el presente proyecto se propone el desarrollo de un sistema de segmentación de artículos RSS, utilizando técnicas de clustering de documentos de manera de agrupar y reconocer los tópicos más relevantes y visualizar los resultados de aplicar el sistema sobre la Web chilena, a través del portal orbitando.com

A síndrome da má absorção (SMA), caracterizada pelo mau desenvolvimento e desuniformidade do lote de aves, causa importantes prejuízos econômicos à avicultura comercial. No entanto, por se tratar de uma doença multifatorial e possivelmente polimicrobiana, o envolvimento do parvovírus de galinha (ChPV) na ocorrência da SMA ainda é pouco conhecido. Com o propósito de elucidar a possível associação entre a presença do ChPV e a ocorrência da SMA, foram desenvolvidas e aplicadas ferramentas moleculares para a detecção e quantificação do ChPV em amostras de frangos comerciais no Estado do Rio Grande do Sul. Uma PCR quantitativa foi desenvolvida para detectar e quantificar cópias do genoma (CG) do ChPV em amostras de suabes de cloaca de 59 frangos saudáveis e 68 frangos com sinais clínicos sugestivos de SMA. Os resultados revelaram que todas as amostras dos dois grupos investigados, continham o genoma do ChPV. No entanto, a carga viral em frangos com SMA foi significativamente (p≤0,0001) maior (1x105 CG/100 ng DNA) do que em frangos saudáveis (1,3x103 CG/100 ng DNA). Adicionalmente às amostras de cloaca, o ChPV também foi investigado em amostras de tecidos (fígado, timo, baço, bursa de Fabricius - BF e intestino) e soros provenientes de nove frangos saudáveis e 50 frangos com sinais indicativos da SMA. O ChPV foi encontrado tanto em aves saudáveis como nas aves com SMA, no entanto, observou-se uma diferença na distribuição deste agente nos tecidos analisados. O genoma do vírus foi mais frequentemente detectado na BF, baço e intestino das aves com SMA, sendo que o intestino foi o tecido que apresentou maior carga viral. Os resultados encontrados nestes estudos demonstraram que o genoma viral estava altamente disseminado nas aves investigadas. Além disso, observou-se uma maior carga viral em frangos de corte com SMA quando comparado com aves sadias. Com base nos resultados encontrados, sugere-se que a maior carga viral de ChPV existente em aves com SMA, em relação a aves saudáveis, seja um dos fatores que favoreça a ocorrência da síndrome. / The malabsorption syndrome (MAS), characterized by the poor development and lack of uniformity of chicken flocks, causes significant economic losses to commercial poultry. However, because it is a multifactorial and possibly polymicrobial disease, the involvement of Chicken parvovirus (ChPV) in the MAS occurrence is still not clear. In order to elucidate the possible association between the presence of ChPV and the occurrence of MAS, molecular tools were developed and applied for the detection and quantification of ChPV DNA in commercial poultry samples in the state of Rio Grande do Sul. A quantitative PCR was developed to detect and quantify the ChPV genome copies (GC) in cloacal swab samples of 59 healthy broilers and 68 broilers with clinical signs suggestive of MAS. The results showed that all investigated samples of the two groups contained the genome ChPV. However, viral loads in MAS-affected animals were significantly (p≤0.0001) higher (1x105 GC/100 ng DNA) than in healthy broilers (1.3x103 GC/100 ng DNA). In addition to the cloacal samples, the presence of ChPV DNA was also investigated in tissue samples (liver, thymus, spleen, bursa of Fabricius - BF and intestine) and sera from nine healthy broilers and 50 broilers with signals indicative of MAS. The ChPV was found in healthy avian as well MAS-affected, however, there was a difference in the distribution of this agent in those tissues. The virus genome was more frequently detected in the BF, spleen and intestines of the MAS-affected broilers, and the intestines contained the highest viral loads, in comparison with other tissues. Our results demonstrated that the viral genome can be found in both healthy and MAS-affected broilers. In addition, higher viral loads were detected in broilers with signs suggestive of MAS compared to healthy birds. Based on these results, it is suggested that the greatest viral load of ChPV existing in MAS-affected broilers when compared to healthy birds, is one of the factors that favor the occurrence of the syndrome.

A síndrome da má absorção (SMA), caracterizada pelo mau desenvolvimento e desuniformidade do lote de aves, causa importantes prejuízos econômicos à avicultura comercial. No entanto, por se tratar de uma doença multifatorial e possivelmente polimicrobiana, o envolvimento do parvovírus de galinha (ChPV) na ocorrência da SMA ainda é pouco conhecido. Com o propósito de elucidar a possível associação entre a presença do ChPV e a ocorrência da SMA, foram desenvolvidas e aplicadas ferramentas moleculares para a detecção e quantificação do ChPV em amostras de frangos comerciais no Estado do Rio Grande do Sul. Uma PCR quantitativa foi desenvolvida para detectar e quantificar cópias do genoma (CG) do ChPV em amostras de suabes de cloaca de 59 frangos saudáveis e 68 frangos com sinais clínicos sugestivos de SMA. Os resultados revelaram que todas as amostras dos dois grupos investigados, continham o genoma do ChPV. No entanto, a carga viral em frangos com SMA foi significativamente (p≤0,0001) maior (1x105 CG/100 ng DNA) do que em frangos saudáveis (1,3x103 CG/100 ng DNA). Adicionalmente às amostras de cloaca, o ChPV também foi investigado em amostras de tecidos (fígado, timo, baço, bursa de Fabricius - BF e intestino) e soros provenientes de nove frangos saudáveis e 50 frangos com sinais indicativos da SMA. O ChPV foi encontrado tanto em aves saudáveis como nas aves com SMA, no entanto, observou-se uma diferença na distribuição deste agente nos tecidos analisados. O genoma do vírus foi mais frequentemente detectado na BF, baço e intestino das aves com SMA, sendo que o intestino foi o tecido que apresentou maior carga viral. Os resultados encontrados nestes estudos demonstraram que o genoma viral estava altamente disseminado nas aves investigadas. Além disso, observou-se uma maior carga viral em frangos de corte com SMA quando comparado com aves sadias. Com base nos resultados encontrados, sugere-se que a maior carga viral de ChPV existente em aves com SMA, em relação a aves saudáveis, seja um dos fatores que favoreça a ocorrência da síndrome. / The malabsorption syndrome (MAS), characterized by the poor development and lack of uniformity of chicken flocks, causes significant economic losses to commercial poultry. However, because it is a multifactorial and possibly polymicrobial disease, the involvement of Chicken parvovirus (ChPV) in the MAS occurrence is still not clear. In order to elucidate the possible association between the presence of ChPV and the occurrence of MAS, molecular tools were developed and applied for the detection and quantification of ChPV DNA in commercial poultry samples in the state of Rio Grande do Sul. A quantitative PCR was developed to detect and quantify the ChPV genome copies (GC) in cloacal swab samples of 59 healthy broilers and 68 broilers with clinical signs suggestive of MAS. The results showed that all investigated samples of the two groups contained the genome ChPV. However, viral loads in MAS-affected animals were significantly (p≤0.0001) higher (1x105 GC/100 ng DNA) than in healthy broilers (1.3x103 GC/100 ng DNA). In addition to the cloacal samples, the presence of ChPV DNA was also investigated in tissue samples (liver, thymus, spleen, bursa of Fabricius - BF and intestine) and sera from nine healthy broilers and 50 broilers with signals indicative of MAS. The ChPV was found in healthy avian as well MAS-affected, however, there was a difference in the distribution of this agent in those tissues. The virus genome was more frequently detected in the BF, spleen and intestines of the MAS-affected broilers, and the intestines contained the highest viral loads, in comparison with other tissues. Our results demonstrated that the viral genome can be found in both healthy and MAS-affected broilers. In addition, higher viral loads were detected in broilers with signs suggestive of MAS compared to healthy birds. Based on these results, it is suggested that the greatest viral load of ChPV existing in MAS-affected broilers when compared to healthy birds, is one of the factors that favor the occurrence of the syndrome.

A síndrome da má absorção (SMA), caracterizada pelo mau desenvolvimento e desuniformidade do lote de aves, causa importantes prejuízos econômicos à avicultura comercial. No entanto, por se tratar de uma doença multifatorial e possivelmente polimicrobiana, o envolvimento do parvovírus de galinha (ChPV) na ocorrência da SMA ainda é pouco conhecido. Com o propósito de elucidar a possível associação entre a presença do ChPV e a ocorrência da SMA, foram desenvolvidas e aplicadas ferramentas moleculares para a detecção e quantificação do ChPV em amostras de frangos comerciais no Estado do Rio Grande do Sul. Uma PCR quantitativa foi desenvolvida para detectar e quantificar cópias do genoma (CG) do ChPV em amostras de suabes de cloaca de 59 frangos saudáveis e 68 frangos com sinais clínicos sugestivos de SMA. Os resultados revelaram que todas as amostras dos dois grupos investigados, continham o genoma do ChPV. No entanto, a carga viral em frangos com SMA foi significativamente (p≤0,0001) maior (1x105 CG/100 ng DNA) do que em frangos saudáveis (1,3x103 CG/100 ng DNA). Adicionalmente às amostras de cloaca, o ChPV também foi investigado em amostras de tecidos (fígado, timo, baço, bursa de Fabricius - BF e intestino) e soros provenientes de nove frangos saudáveis e 50 frangos com sinais indicativos da SMA. O ChPV foi encontrado tanto em aves saudáveis como nas aves com SMA, no entanto, observou-se uma diferença na distribuição deste agente nos tecidos analisados. O genoma do vírus foi mais frequentemente detectado na BF, baço e intestino das aves com SMA, sendo que o intestino foi o tecido que apresentou maior carga viral. Os resultados encontrados nestes estudos demonstraram que o genoma viral estava altamente disseminado nas aves investigadas. Além disso, observou-se uma maior carga viral em frangos de corte com SMA quando comparado com aves sadias. Com base nos resultados encontrados, sugere-se que a maior carga viral de ChPV existente em aves com SMA, em relação a aves saudáveis, seja um dos fatores que favoreça a ocorrência da síndrome. / The malabsorption syndrome (MAS), characterized by the poor development and lack of uniformity of chicken flocks, causes significant economic losses to commercial poultry. However, because it is a multifactorial and possibly polymicrobial disease, the involvement of Chicken parvovirus (ChPV) in the MAS occurrence is still not clear. In order to elucidate the possible association between the presence of ChPV and the occurrence of MAS, molecular tools were developed and applied for the detection and quantification of ChPV DNA in commercial poultry samples in the state of Rio Grande do Sul. A quantitative PCR was developed to detect and quantify the ChPV genome copies (GC) in cloacal swab samples of 59 healthy broilers and 68 broilers with clinical signs suggestive of MAS. The results showed that all investigated samples of the two groups contained the genome ChPV. However, viral loads in MAS-affected animals were significantly (p≤0.0001) higher (1x105 GC/100 ng DNA) than in healthy broilers (1.3x103 GC/100 ng DNA). In addition to the cloacal samples, the presence of ChPV DNA was also investigated in tissue samples (liver, thymus, spleen, bursa of Fabricius - BF and intestine) and sera from nine healthy broilers and 50 broilers with signals indicative of MAS. The ChPV was found in healthy avian as well MAS-affected, however, there was a difference in the distribution of this agent in those tissues. The virus genome was more frequently detected in the BF, spleen and intestines of the MAS-affected broilers, and the intestines contained the highest viral loads, in comparison with other tissues. Our results demonstrated that the viral genome can be found in both healthy and MAS-affected broilers. In addition, higher viral loads were detected in broilers with signs suggestive of MAS compared to healthy birds. Based on these results, it is suggested that the greatest viral load of ChPV existing in MAS-affected broilers when compared to healthy birds, is one of the factors that favor the occurrence of the syndrome.

Made available in DSpace on 2014-06-12T16:00:55Z (GMT). No. of bitstreams: 2 arquivo7078_1.pdf: 1059090 bytes, checksum: a479e2eb412f2dbffd1dfe678ea6ef33 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2011 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Os sistemas de localização RFID com etiquetas ativas são os mais promissores para o provimento de serviços de localização automática de objetos em ambientes internos. Esses sistemas contam com medidas de força de sinais e com uma infraestrutura de leitores e etiquetas de referência para a obtenção de estimativas de localização de objetos de interesse. Esta dissertação estuda a influência do posicionamento dessa infraestrutura na eficiência de localização. Para isso, considera-se 27 configurações de posicionamento da infraestrutura de localização e diversas condições de propagação de sinais em um ambiente interno com 9 salas ou áreas. O foco desta dissertação está nos sistemas LANDMARC e LANDMARC+, onde ambos estão configurados para estimar a sala ou área na qual se encontra um objeto de interesse. Os resultados de simulação mostram que o posicionamento da infraestrutura dos sistemas estudados tem impacto significativo na eficiência de localização. A partir disso, são apresentadas orientações para um posicionamento mais adequado dessa infraestrutura, buscando a maximização da eficiência de localização