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Ανάλυση περιεχομένου τηλεοπτικών διαφημίσεων μη συνταγογραφούμενων (OTC) φαρμάκωνΣιμονοβίκης, Σταύρος 30 July 2014 (has links)
Η εργασία που ακολoυθεί εκπονήθηκε στα πλαίσια του μεταπτυχιακού
προγράμματος σπουδών "Φαρμακευτικό Μάρκετινγκ", του τμήματος Φαρμακευτικής
του Πανεπιστήμιου Πατρών, κατά την ακαδημαϊκή περίοδο σπουδών 2009-2011.
Σκοπός της έρευνας ήταν να γίνει μια εκτίμηση της κατάστασης στο χώρο της αγοράς
των μη υποχρεωτικώς συνταγογραφούμενων φαρμάκων, έχοντας υπόψη τις
διαφημιστικές στρατηγικές που εφαρμόζονται από τις φαρμακευτικές εταιρίες, καθώς
επίσης και άλλων προϊόντων που διατίθενται από τα φαρμακεία. Στα προϊόντα αυτά
περιλαμβάνονται συμπληρώματα διατροφής, υποκατάστατα νικοτίνης για τη ρύθμιση
της διάθεσης για κάπνισμα, προϊόντα για το αδυνάτισμα, προϊόντα στοματικής
υγιεινής, κρέμες για αντηλιακή προστασία, για αντιγήρανση και ενυδάτωση κ.ά.
Για την πραγματοποίηση της παρούσας μελέτης συλλέχτηκαν οι τηλεοπτικές
διαφημίσεις των προϊόντων αυτών είτε από τις διαφημιστικές εταιρείες είτε από το
διαδίκτυο προκειμένου να αναλυθούν. Τα διαφημιστικά που αναλύσαμε ήταν 78 και
τα δεδομένα που προέκυψαν αναλύθηκαν με τη βοήθεια του στατιστικού
προγράμματος SPSS. Πραγματοποιήσαμε ανάλυση παραγόντων (factor analysis) από
την οποία προέκυψαν 14 διαφορετικά προφίλ διαφημίσεων. Τα ερευνητικά
συμπεράσματα υποδεικνύουν πως στις διαφημίσεις χρησιμοποιούνται σε υψηλό
ποσοστό πληροφοριακά στοιχεία (ποιότητα, απόδοση και συστατικά μέρη/στοιχεία)
καθώς επίσης και πληθώρα διαφημιστικών εκτελεστικών στυλ με κυρίαρχα: το
κομμάτι της καθημερινότητας, φαντασία/όνειρο και διάθεση/εικόνα. / The following research was acomplished for the Master Program "Pharmaceutical Marketing" during the academic year 2009-2011. The purpose of this study is to conduct a content analysis of the advertisements of OTC products. The advertisements contain food supplements, NRT, diet products as well as dental hygiene products. In order to perform the content analysis, 78 television ads were collected and then analysed using SPSS. From the factor analysis that we performed we came up with 14 different kinds (profiles)of advertisments. The main conclusions dictate that in OTC advertisments are extensively used informational clues regarding the quality, the performance and the parts of its product. Moreover, a variety of advertising executive styles are also used, such as slice of life and fantasy dream.
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Efeitos de diferentes exercícios de força com intensidade preferida ou prescrita sobre a dor em mulheres com fibromialgia / Effects of different strength exercises with preferred or prescribed intensity on pain in women with fibromyalgiaRibeiro, Roberta Potenza da Cunha 09 November 2017 (has links)
Exercícios de força com intensidade preferida ou prescrita resultam em efeitos analgésicos semelhantes em pacientes com FM, sugerindo que o modelo de treinamento deve ser recomendado para melhorar a aderência ao exercício. O objetivo foi comparar o efeito de sessões de exercícios de força com intensidade preferida e prescrita na dor de pacientes com FM. De forma aleatória, as mulheres do sexo feminino (n = 32, idade 20-55 anos) foram submetidas às seguintes sessões de exercício: i) prescrição padrão (STD, 6 x 10 repetições com 60% de uma repetição máxima); ii) carga auto-selecionada com número fixo de repetições (SS); iii) carga auto-selecionada com volume total correspondente ao volume STD (SS-VM); e iii) carga auto-selecionada com um número livre de repetições até atingir o escore 7 na Escala de Percepção ao esforço (SS-PSE). A dor foi avaliada através da Escala Visual Analógica (EVA) e do Questionário de Dor de McGill Short-Form (SF-MPQ) antes imediatamente após e 24, 48, 72 e 96 horas após as sessões de exercícios de força. O humor, escala de afetividade ao exercício e a PSE da sessão também foram medidos. A intensidade foi significativamente menor em SS, SS-VM, SS-PSE do que em STD, enquanto o volume total, humor, afetividade ao exercício e PSE não tiveram diferença entre as sessões. As pontuações de VAS também aumentaram imediatamente após todas as sessões de exercício (p < 0,0001) e, em seguida, reduziram significativamente após 48, 72, 96 h (p < 0,0001), permanecendo elevada em relação aos prévalores. Os valores de SF-MPQ aumentaram significativamente imediatamente após todas as sessões de exercício de resistência (p = 0,025), depois diminuíram gradualmente ao longo do tempo, atingindo os níveis basais às 24 h. Não houve efeito de interação significativa para a dor. As sessões de exercício de força prescrita e preferida não foram capaz de induzir analgesia em pacientes com FM, sugerindo que os modelos de exercícios de força que levem a menores intensidades percebidas podem ser necessários para superar essa resposta anormal nesta síndrome / Preferable and prescribed resistance exercises result similar analgesic effects in FM patients suggesting that the training model should be recommended to improve exercise adherence. Compare the effect of preferred and prescribed resistance exercises on pain in FM patients. In a randomized cross-over fashion, FM female patients (n = 32, age 20-55 years) underwent the following exercise sessions: i) standard prescription (STD; 6 x 10 repetitions at 60% of one-maximum repetition); ii) self-selected load with fixed number of repetitions (SS); iii) self-selected load with total volume matched for STD volume (SS-VM); and iii) self-selected load with a free number of repetitions until achieving score 7 in the rating of perceived exertion (SS-RPE). Pain was assessed through the Visual Analogic Scale (VAS) and the Short-Form McGill Pain Questionnaire (SF-MPQ) before and 0, 24, 48, 72 and 96 hours after the resistance exercise sessions. Mood, affective valence scale and session RPE were also measured. Intensity was significantly lower in SS, SS-VM, SS-RPE than in STD, whereas total volume, mood, affective and RPE were comparable between the sessions. VAS scores equally increased immediately after all the exercise sessions (p < 0.0001), and then significantly reduced after 48, 72, 96 h (p < 0.0001), remaining elevated as compared to pre-values. SF-MPQ values significantly increased immediately after all the resistance exercise sessions (p = 0.025), then gradually reduced across time, reaching baseline levels at 24 h. There was no significant interaction effect for pain. Prescribed and preferable resistance exercise equally failed to induce analgesia in FM patients, suggesting that resistance exercise models leading to lower perceived intensities might be needed to overcome this dysfunctional response in this syndromes
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Efeitos de diferentes exercícios de força com intensidade preferida ou prescrita sobre a dor em mulheres com fibromialgia / Effects of different strength exercises with preferred or prescribed intensity on pain in women with fibromyalgiaRoberta Potenza da Cunha Ribeiro 09 November 2017 (has links)
Exercícios de força com intensidade preferida ou prescrita resultam em efeitos analgésicos semelhantes em pacientes com FM, sugerindo que o modelo de treinamento deve ser recomendado para melhorar a aderência ao exercício. O objetivo foi comparar o efeito de sessões de exercícios de força com intensidade preferida e prescrita na dor de pacientes com FM. De forma aleatória, as mulheres do sexo feminino (n = 32, idade 20-55 anos) foram submetidas às seguintes sessões de exercício: i) prescrição padrão (STD, 6 x 10 repetições com 60% de uma repetição máxima); ii) carga auto-selecionada com número fixo de repetições (SS); iii) carga auto-selecionada com volume total correspondente ao volume STD (SS-VM); e iii) carga auto-selecionada com um número livre de repetições até atingir o escore 7 na Escala de Percepção ao esforço (SS-PSE). A dor foi avaliada através da Escala Visual Analógica (EVA) e do Questionário de Dor de McGill Short-Form (SF-MPQ) antes imediatamente após e 24, 48, 72 e 96 horas após as sessões de exercícios de força. O humor, escala de afetividade ao exercício e a PSE da sessão também foram medidos. A intensidade foi significativamente menor em SS, SS-VM, SS-PSE do que em STD, enquanto o volume total, humor, afetividade ao exercício e PSE não tiveram diferença entre as sessões. As pontuações de VAS também aumentaram imediatamente após todas as sessões de exercício (p < 0,0001) e, em seguida, reduziram significativamente após 48, 72, 96 h (p < 0,0001), permanecendo elevada em relação aos prévalores. Os valores de SF-MPQ aumentaram significativamente imediatamente após todas as sessões de exercício de resistência (p = 0,025), depois diminuíram gradualmente ao longo do tempo, atingindo os níveis basais às 24 h. Não houve efeito de interação significativa para a dor. As sessões de exercício de força prescrita e preferida não foram capaz de induzir analgesia em pacientes com FM, sugerindo que os modelos de exercícios de força que levem a menores intensidades percebidas podem ser necessários para superar essa resposta anormal nesta síndrome / Preferable and prescribed resistance exercises result similar analgesic effects in FM patients suggesting that the training model should be recommended to improve exercise adherence. Compare the effect of preferred and prescribed resistance exercises on pain in FM patients. In a randomized cross-over fashion, FM female patients (n = 32, age 20-55 years) underwent the following exercise sessions: i) standard prescription (STD; 6 x 10 repetitions at 60% of one-maximum repetition); ii) self-selected load with fixed number of repetitions (SS); iii) self-selected load with total volume matched for STD volume (SS-VM); and iii) self-selected load with a free number of repetitions until achieving score 7 in the rating of perceived exertion (SS-RPE). Pain was assessed through the Visual Analogic Scale (VAS) and the Short-Form McGill Pain Questionnaire (SF-MPQ) before and 0, 24, 48, 72 and 96 hours after the resistance exercise sessions. Mood, affective valence scale and session RPE were also measured. Intensity was significantly lower in SS, SS-VM, SS-RPE than in STD, whereas total volume, mood, affective and RPE were comparable between the sessions. VAS scores equally increased immediately after all the exercise sessions (p < 0.0001), and then significantly reduced after 48, 72, 96 h (p < 0.0001), remaining elevated as compared to pre-values. SF-MPQ values significantly increased immediately after all the resistance exercise sessions (p = 0.025), then gradually reduced across time, reaching baseline levels at 24 h. There was no significant interaction effect for pain. Prescribed and preferable resistance exercise equally failed to induce analgesia in FM patients, suggesting that resistance exercise models leading to lower perceived intensities might be needed to overcome this dysfunctional response in this syndromes
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Avaliação de desempenho de mecanismos de segurança em ambientes PACS (Picture Archiving and Communication System) baseados em computação em nuvem / Performance evaluation of security mechanisms in PACS environments (Picture Archiving and Communication System) based on cloud computingSant\'Ana, Fábio Sousa de 07 November 2016 (has links)
Introdução: A adoção de um Sistema de Arquivamento e Distribuição de Imagens (PACS, do inglês Picture Archiving and Communication System) é condição fundamental para a estruturação de um ambiente radiológico sem filme. Um PACS é composto basicamente por equipamentos e sistemas informatizados interconectados em rede, direcionados à aquisição, armazenamento (ou arquivamento), recuperação e apresentação de imagens médicas aos especialistas responsáveis por avaliá-las e laudá-las. A computação em nuvem vem ao encontro dos PACS e surge como uma maneira de simplificar o compartilhamento de imagens entre organizações de saúde e promover a virtualização de espaços físicos e para garantir o seu funcionamento ininterrupto.Objetivo: Este estudo teve como objetivo implementar um PACS simplificado em ambiente cloud computing privado, com foco nas funcionalidades de arquivamento e disponibilização de imagens médicas e avaliar questões de segurança e performance. Metodologia: As imagens que compuseram o PACS do ambiente cloud foram obtidas através do PACS físico atualmente em uso no Centro de Ciência das Imagens e Física Médica do Hospital das Clinicas da Faculdade de Medicina de Ribeirão Preto - CCIFM/HCFMRP. Para os procedimentos da avaliação de segurança foram construídos cenários que possibilitavam a: 1) anominização de dados de identificação dos pacientes através de criptografia computacional em base de dados utilizando o algoritmo de criptografia Advanced Encryption Standard - AES, 2) transferência de imagens médicas seguras através de conexão com a Internet utilizando Virtual Network Private - VPN sobre o protocolo Internet Protocol Security - IPSec (VPN/IPSec) e 3) envio seguro através de tunelamento baseado em Secure Shell - SSH. Resultados: Foi identificada uma queda de performance no envio de informações para a nuvem quando submetidos aos níveis de segurança propostos, sugerindo a relação entre aumento de segurança e perda de performance, apontando para a necessidade de estudos de desempenho quando da condução de projetos envolvam a adoção em ambientes clínicos de solução PACS baseada em cloud computing. / Introduction: the adoption of a PCAS (Picture Archiving and Communication System) is fundamental for the structuring of a radiological environment without film. A PACS comprises, essentially, hardware and information systems interconnected in a network, oriented towards acquisition, storage (or archiving), retrieving and presentation of medical images to specialists entrusted with analyzing and assessing them. Cloud computing comes to support of PCAS, simplifying medical imaging sharing between health care organizations and promoting the virtualization of physical infrastructure to assure uninterrupted availability of the PCAS. Goal: This study aimed to implement a simplified PCAS in a private cloud computing environment, and subsequently to evaluate its security and performance. Methodology: The images that formed the new PCAS were obtained from the exiting PCAS of Centro de Ciência das Imagens e Física Médica of Hospital das Clinicas da Faculdade de Medicina de Ribeirão Preto - CCIFM/HCFMRP. To evaluate its security, scenarios were built within the following framework: 1) patient identification data anonymization through computational database cryptography, using the AES (Advanced Encription Standards) algorithm ; 2) transfer of encrypted medical images on the Internet using VPN (Virtual Private Network) over IPSec (Internet Protocol Security); and 3) safe traffic through Secure Shell (SSH) tunneling. Results: There was a performance drop on traffic of information to the cloud under the proposed security levels that suggests a relationship between increase in security and loss of performance, pointing to the need for performance studies when the project involving driving adoption in clinical environments PACS solution based on cloud computing.
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Handling Over-Constrained Temporal Constraint NetworksBeaumont, Matthew, n/a January 2004 (has links)
Temporal reasoning has been an active research area for over twenty years, with most work focussing on either enhancing the efficiency of current temporal reasoning algorithms or enriching the existing algebras. However, there has been little research into handling over-constrained temporal problems except to recognise that a problem is over-constrained and then to terminate. As many real-world temporal reasoning problems are inherently over-constrained, particularly in the scheduling domain, there is a significant need for approaches that can handle over-constrained situations. In this thesis, we propose two backtracking algorithms to gain partial solutions to over-constrained temporal problems. We also propose a new representation, the end-point ordering model, to allow the use of local search algorithms for temporal reasoning. Using this model we propose a constraint weighting local search algorithm as well as tabu and random-restart algorithms to gain partial solutions to over-constrained temporal problems. Specifically, the contributions of this thesis are: The introduction and empirical evaluation of two backtracking algorithms to solve over-constrained temporal problems. We provide two backtracking algorithms to close the gap in current temporal research to solve over-constrained problems; The representation of temporal constraint networks using the end-point ordering model. As current representation models are not suited for local search algorithms, we develop a new model such that local search can be applied efficiently to temporal reasoning; The development of a constraint weighting local search algorithm for under-constrained problems. As constraint weighting has proven to be efficient for solving many CSP problems, we implement a constraint weighting algorithm to solve under-constrained temporal problems; An empirical evaluation of constraint weighting local search against traditional backtracking algorithms. We compare the results of a constraint weighting algorithm with traditional backtracking approaches and find that in many cases constraint weighting has superior performance; The development of a constraint weighting local search, tabu search and random-restart local search algorithm for over-constrained temporal problems. We extend our constraint weighting algorithm to solve under-constrained temporal problems as well as implement two other popular local search algorithms: tabu search and random-restart; An empirical evaluation of all three local search algorithms against the two backtracking algorithms. We compare the results of all three local search algorithms with our twobacktracking algorithms for solving over-constrained temporal reasoning problems and find that local search proves to be considerably superior.
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Stability analysis of mobile boom cranesRauch, Andreas 08 August 2008 (has links)
Mobile boom cranes are used throughout the world to perform important and dangerous manipulation tasks. Given their mobility, these types of cranes can quickly be moved into position. Generally, their base is then fixed and stabilized before they start lifting heavy materials. The usefulness of these cranes can be greatly improved if they can utilize their mobile base during the lifting and transferring phases of operation. This ability greatly expands the workspace by combining base motion with the rotation, lifting, and luffing motions. Of course, the cranes lose some stability margin when a payload is attached. The stability is further degraded when the payload swings. This Master's Thesis presents a stability study of such cranes. As a first step, a static stability analysis of a boom crane is conducted in order to provide basic insights into the effects of the payload weight and crane configuration. Then, a semi-dynamic method is used to take the payload swing into account. As a final step, the results of a dynamic stability analysis obtained by using a multi-body simulation of the boom crane are compared to the outcomes of the previous approaches. This provides conclusions for the practical application of stability analysis. A control method that limits payload swing, and thereby improves stability, is also presented.
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Avaliação de desempenho de mecanismos de segurança em ambientes PACS (Picture Archiving and Communication System) baseados em computação em nuvem / Performance evaluation of security mechanisms in PACS environments (Picture Archiving and Communication System) based on cloud computingFábio Sousa de Sant\'Ana 07 November 2016 (has links)
Introdução: A adoção de um Sistema de Arquivamento e Distribuição de Imagens (PACS, do inglês Picture Archiving and Communication System) é condição fundamental para a estruturação de um ambiente radiológico sem filme. Um PACS é composto basicamente por equipamentos e sistemas informatizados interconectados em rede, direcionados à aquisição, armazenamento (ou arquivamento), recuperação e apresentação de imagens médicas aos especialistas responsáveis por avaliá-las e laudá-las. A computação em nuvem vem ao encontro dos PACS e surge como uma maneira de simplificar o compartilhamento de imagens entre organizações de saúde e promover a virtualização de espaços físicos e para garantir o seu funcionamento ininterrupto.Objetivo: Este estudo teve como objetivo implementar um PACS simplificado em ambiente cloud computing privado, com foco nas funcionalidades de arquivamento e disponibilização de imagens médicas e avaliar questões de segurança e performance. Metodologia: As imagens que compuseram o PACS do ambiente cloud foram obtidas através do PACS físico atualmente em uso no Centro de Ciência das Imagens e Física Médica do Hospital das Clinicas da Faculdade de Medicina de Ribeirão Preto - CCIFM/HCFMRP. Para os procedimentos da avaliação de segurança foram construídos cenários que possibilitavam a: 1) anominização de dados de identificação dos pacientes através de criptografia computacional em base de dados utilizando o algoritmo de criptografia Advanced Encryption Standard - AES, 2) transferência de imagens médicas seguras através de conexão com a Internet utilizando Virtual Network Private - VPN sobre o protocolo Internet Protocol Security - IPSec (VPN/IPSec) e 3) envio seguro através de tunelamento baseado em Secure Shell - SSH. Resultados: Foi identificada uma queda de performance no envio de informações para a nuvem quando submetidos aos níveis de segurança propostos, sugerindo a relação entre aumento de segurança e perda de performance, apontando para a necessidade de estudos de desempenho quando da condução de projetos envolvam a adoção em ambientes clínicos de solução PACS baseada em cloud computing. / Introduction: the adoption of a PCAS (Picture Archiving and Communication System) is fundamental for the structuring of a radiological environment without film. A PACS comprises, essentially, hardware and information systems interconnected in a network, oriented towards acquisition, storage (or archiving), retrieving and presentation of medical images to specialists entrusted with analyzing and assessing them. Cloud computing comes to support of PCAS, simplifying medical imaging sharing between health care organizations and promoting the virtualization of physical infrastructure to assure uninterrupted availability of the PCAS. Goal: This study aimed to implement a simplified PCAS in a private cloud computing environment, and subsequently to evaluate its security and performance. Methodology: The images that formed the new PCAS were obtained from the exiting PCAS of Centro de Ciência das Imagens e Física Médica of Hospital das Clinicas da Faculdade de Medicina de Ribeirão Preto - CCIFM/HCFMRP. To evaluate its security, scenarios were built within the following framework: 1) patient identification data anonymization through computational database cryptography, using the AES (Advanced Encription Standards) algorithm ; 2) transfer of encrypted medical images on the Internet using VPN (Virtual Private Network) over IPSec (Internet Protocol Security); and 3) safe traffic through Secure Shell (SSH) tunneling. Results: There was a performance drop on traffic of information to the cloud under the proposed security levels that suggests a relationship between increase in security and loss of performance, pointing to the need for performance studies when the project involving driving adoption in clinical environments PACS solution based on cloud computing.
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Diversité et déterminisme génétique de la recombinaison méiotique chez Saccharomyces cerevisiae / Diversity and genetic determinsim of meiotic recombination rate in Saccharomyces cerevisiaeRaffoux, Xavier 06 November 2018 (has links)
L’agriculture moderne doit assurer notre sécurité alimentaire dans le contexte d’un changement climatique qui entraîne une baisse des rendements. Une meilleure compréhension des facteurs contrôlant la recombinaison méiotique ouvrirait la voie à la modification du nombre et de la répartition des crossing-overs, ce qui permettrait une localisation plus précise des facteurs génétiques contrôlant les caractères d’intérêt agronomique et faciliterait le pyramidage d’allèles favorables au sein d’un même génotype élite. Pendant ma thèse, j’ai développé une méthode de mesure à haut débit de la recombinaison chez la levure Saccharomyces cerevisiae pour étudier la diversité de la recombinaison et de l’interférence au sein d’une collection de 24 souches représentatives de la diversité de l’espèce ainsi qu’au sein d’un dispositif di-allèle à cinq parents. Les résultats montrent un nombre moyen de crossing-overs par méiose compris entre 24 et 61, ce qui est plus élevé que chez la majorité des autres espèces. Plus particulièrement, les profils de recombinaison diffèrent entre souches, atteignant un écart d’un facteur 9 dans certaines régions. Les souches originaires d’habitats peu stables n’ont cependant pas un niveau de recombinaison plus élevé que les souches originaires d’environnements stables. En outre, la plupart des souches montrent de l’interférence dont la force est corrélée positivement avec le niveau de recombinaison. L’étude de la relation entre niveau de recombinaison et similarité de séquence entre homologues, à différentes échelles locales ou globales, indique que la recombinaison est contrôlée à la fois par des éléments cis et des facteurs trans. Par ailleurs, l’hétérozygotie chez les hybrides a un effet négatif sur le niveau de recombinaison, mais les homozygotes ont aussi un niveau de recombinaison réduit par un effet de dépression de consanguinité. Ce travail permettra maintenant d’étudier la réponse de la recombinaison à la sélection et de détecter les QTL de nombre de crossing-overs, afin d’identifier des gènes qui contrôlent la recombinaison. / Modern agriculture must ensure food security in a context of climate change that will lower yields. A better understanding of the factors controlling meiotic recombination could pave the way to modifying the number and distribution of crossing-over, which would allow a more precise localization of genetic factors controlling agronomic traits, and facilitate gene pyramiding in selection programs. During my thesis, I developed a method for high-throughput measurement of recombination rates in the yeast Saccharomyces cerevisiae. This allowed me to study the diversity of recombination and interference in a collection of 24 strains representing most of the diversity of the species, as well as within a five-parent di-allele design. The results show an average number of crossovers per meiosis ranging between 24 and 61, higher than in the majority of other species. Furthermore, recombination patterns differ between strains, and ratios of local recombination rates show 9-fold differences in some regions. Strains from unstable habitats, however, do not have a higher level of recombination than those from stable environments. In addition, most strains show interference whose strength is positively correlated with the level of recombination. The study of the relationship between recombination rate and sequence similarity between homologs at different scales (from local to global) indicates that recombination is controlled by both cis elements and trans factors. Lastly, heterozygosity in hybrids has a negative effect on crossing-over, but homozygotes also have a reduced level of recombination due to inbreeding depression. This work will now be used to study the response of recombination to selection and to detect QTL of crossover number in order to identify genes controlling recombination.
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Optical generation of mm-wave signals for use in broadband radio over fiber systemsGonzález Insua, Ignacio 04 February 2010 (has links)
In future cellular radio networks Radio over Fiber (RoF) is a very attractive technology to deliver microwave and millimeter-wave signals containing broad band multimedia services to numerous base stations of the network. The radio signals are placed on an optical carrier and distributed by means of an optical fiber network to the base stations (BS). In the BS the optical signals heterodyne in a photodiode to produce the radio signals which are then sent via a wireless link to the mobile units (MU). The optical fiber network provides high frequency, wideband, low loss and a means of signal distribution immune to electromagnetic interference. In this thesis, different methods of electrooptical upconversion were investigated. The generation of an optical double-sideband with suppressed carrier (DSB-SC) signal is a straightforward method due to the fact that only one optical modulator driven at half the millimeter-wave frequency is required. One or both sidebands were ASK-modulated with baseband data rates of up to 10 Gbps. Optical single sideband modulation proves to be dispersion resilient as error free transmission was demonstrated after 53 km of single mode fiber transmission for data rates up to 10 Gbps. Wireless links up to 7 m were also demonstrated, proving the feasibility of this approach for broadband wireless inhouse access systems. / Für zukünftige zellulare Funknetze ist „Radio over Fiber (RoF)“ eine sehr attraktive Technologie, um breitbandige Multimedia-Dienste mit Mikro- und Millimeterwellen zu übertragen. Die Funksignale werden dabei auf eine optische Trägerwelle aufmoduliert und mittels eines optischen Fasernetzes zu den Basisstationen (BS) verteilt. In den BS erfolgt die Überlagung der optischen Signale durch eine Fotodiode, um die Funksignale zu erzeugen. Diese werden dann über eine drahtlose Verbindung zu den beweglichen Multimedia-Endgeräten geschickt. Vorteile des optischen Fasernetzes sind Breitbandigkeit, geringe Dämpfung und eine gegenüber elektromagnetischen Störungen immune Signalverteilung. In dieser Arbeit werden verschiedene Methoden der elektrooptischen Aufwärtskonversion erforscht und die wichtigsten Eigenschaften dieser untersucht. Die Erzeugung eines optischen Zweiseitenbandsignales mit unterdrücktem Träger (DSB-SC) ist eine einfache Methode, da nur ein optischer Modulator, betrieben mit der halben elektrischen Trägerfrequenz, benötigt wird. Eine oder beide Seitenbänder konnten mit Bitraten bis zu 10 Gbps amplitudenmoduliert werden. Optische Einseitenbandmodulation ist extrem tolerant bezüglich der chromatischen Dispersion der Faser, wie die fehlerfreie Übertragung nach 53 km Glasfaser beweist. Drahtlose Links bis zu 7 m wurden realisiert und zeigen die Möglichkeit dieser Verfahren für breitbandige drahtlose Inhouse-Zugangssysteme.
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Předlužení mladé generace v ČR / Over-indebtedness of young people in the Czech RepublicLišková, Veronika January 2016 (has links)
The master's thesis "Over-indebtedness of Young Generation in the Czech Republic" deals with over-indebtedness of individuals at the age of 18 to 26 years. Over-indebtedness is a general social problem as all age groups get overburdened with debt. However, it is important to focus on the issue of young people's over-indebtedness directly because the young generation represents people who are or will be active in the general working process. The authoress of the thesis points out the young generation's over-indebtedness and provides an overview of development of this issue in 2008 - 2015. She also examines the most frequent causes which she has found out using questionnaires and data collected. In her work, the authoress also outlines a gradual development of possible indebtedness, which primarily includes loans, from both banks and other institutions, followed by a court procedure and execution of the judgement. A possible solution to over-indebtedness then consists in filing a petition with a court to permit a personal discharge from debts. The work aims at finding out and examining development of the young generation's indebtedness in the Czech Republic, analysing causes of over-indebtedness, describing the changes of the causes in time and at analysing the process of discharge from debts, which...
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