The objective of this study was to examine the effectiveness of alternative advertising presentation formats, and the quantity of information presented in advertisements in overcoming possible information-processing deficits in senior adults that could affect their recall of ad attributes and brand name, the cognitive responses generated, and attitude toward the ad. In addition, the study examined the effectiveness of retirement status as a classification or segmentation variable in comparison with the use of the more traditional classification variable, chronological age. A convenience sample of senior adult volunteers from church groups, social clubs, and civic organizations from the local area were randomly assigned to one of nine experimental conditions. The experiment utilized a simulated magazine to test the effects of presentation formats (3 levels), and quantity of information (3 levels) on senior adult's recall, cognitive responses and attitude toward the test ads. Covariates (gender, wealth, education, activity level, health, and income) were used to reduce variance. The findings clearly indicate that the presentation format of the can ad adversely affected the memory of some senior adults. In addition, the results were significantly different across the different age levels. Retirement status was less beneficial than chronological age in the current study, but did reveal a marginally significant difference between seniors due to the number of attributes contained in the test ads. The implication of findings for advertisers and those who design marketing communications for seniors are numerous, and relate to the marketer's communication goals. Senior adults may prefer print media, but the inappropriate use of presentation format and the number of product attributes in the ads could have an adverse and significant impact when communicating with senior adults. Recognition of the information-processing differences of senior adults would result in more effective marketing communications for this rapidly growing and important segment of our society.

L'endothélium constitue un véritable organe qui sécrète de nombreuses substances vasoactives régissant des fonctions cardiovasculaires vitales telles que le tonus et la croissance vasculaires. Ce tissu requiert la polyvalence de la signalisation calcique puisque plusieurs de ses fonctions dépendent de la modulation de la concentration intracellulaire de Ca[indice supérieur 2+].L'un des moyens utilisés par les cellules endothéliales pour assurer une réponse calcique efficace et spécifique est la propagation des signaux sous forme de vagues. Dans ce travail, nous avons décortiqué les mécanismes de mobilisation du Ca[indice supérieur 2+] intracellulaire menant à la propagation de vagues de Ca[indice supérieur 2+]. Nous avons recueilli des données qui aideront à mieux comprendre à la fois l'organisation et la propagation de vagues de Ca[indice supérieur 2+] dans les cellules endothéliales d'aorte de boeuf (BAEC). Nous montrons par vidéomicroscopie, que la stimulation des BAEC avec l'ATP ou avec la bradykinine (BIC) induit une réponse calcique oscillatoire finement régulée dans le temps et dans l'espace. En fait, le Ca[indice supérieur 2+] se propage d'une extrémité à l'autre de la cellule sous la forme d'une vague qui se produit en présence ou en absence de Ca[indice supérieur 2+] extracellulaire. Bien que les vagues de Ca[indice supérieur 2+] soient initiées à un endroit très précis près de la membrane plasmique, les cavéoles ne sont pas essentielles à leur propagation dans les BAEC, contrairement à ce qui a été observé dans certains autres types cellulaires. Toutefois, la dépolymérisation des microfilaments avec la latrunculine B et des microtubules avec la colchicine empêche la propagation de la vague de Ca[indice supérieur 2+]. Dans ces conditions, les BAEC présentent plutôt une augmentation calcique uniforme dans toute la cellule. Ces résultats suggèrent que, dans les BAEC, les cavéoles ne sont pas impliquées dans l'organisation de la réponse calcique sous forme de vague, mais que l'organisation du cytosquelette est essentielle. Nous montrons aussi que la vitesse de propagation de la vague de Ca[indice supérieur 2+] est constante d'un bout à l'autre d'une BAEC, ce qui est incompatible avec un mécanisme impliquant uniquement la diffusion de l'IP[indice inférieur 3] ou du Ca[indice supérieur 2+]. Nous montrons également que la vitesse de propagation de la vague de Ca[indice supérieur 2+] dépend de l'intensité de la stimulation et aussi de l'état fonctionnel de l'IP[indice inférieur 3]R qui peut être modulé par des kinases endogènes comme la PKA, la PKC et mTOR. Enfin, nous montrons que la vitesse de propagation de la vague de Ca[indice supérieur 2+] n'est pas directement reliée à l'amplitude de la relâche de Ca[indice supérieur 2+]. La vitesse de propagation des vagues de Ca[indice supérieur 2+] est un paramètre relativement nouveau dans le domaine de la signalisation calcique intracellulaire. Il reste à définir jusqu'à quel point ce paramètre peut être utile dans l'interprétation des différentes activités cellulaires.

Approved for public release, distribution is unlimited / With the rapidly growing demand for portable devices such as laptops, handheld computers and Personal Digital Assistants (PDAs) with wireless networking capabilities, the need for reliable wireless data network communication has also increased. Just like in mobile voice communication, users demand uninterrupted, secure wireless data communication as they move from place to place. Mobile IP satisfies some of these demands - it enables mobile devices with fixed IP addresses to be permanently reachable even as their point of attachment to the network changes. This allows for routing of data packets to and from the mobile device irrespective of its location on the network. While uninterrupted data flow can be achieved with Mobile IP, it introduces additional security vulnerabilities, including data privacy, data integrity and authentication. The goal of this thesis is to investigate such vulnerabilities and explore implementations to overcome them. / Civilian, National Science Foundation

This thesis presents research on transport layer behavior in wireless networks. As the Internet is expanding its reach to include mobile devices, it has become apparent that some of the original design assumptions for the dominant transport protocol, TCP, are approaching their limits. A key feature of TCP is the congestion control algorithm, constructed with the assumption that packet loss is normally very low, and that packet loss therefore is a sign of network congestion. This holds true for wired networks, but for mobile wireless networks non-congestion related packet loss may appear. The varying signal power inherent with mobility and handover between base-stations are two example causes of such packet loss. This thesis provides an overview of the challenges for TCP in wireless networks together with a compilation of a number of suggested TCP optimizations for these environments. A TCP modification called TCP-L is proposed. It allows an application to increase its performance, in environments where residual bit errors normally give a degraded throughput, by making a reliability tradeoff. The performance of TCP-L is experimentally evaluated with an implementation in the Linux kernel. The transport layer performance in a 4G scenario is also experimentally investigated, focusing on the impact of the link layer design and its parameterization. Further, for emulation-based protocol evaluations, controlled packet loss and bit error generation is shown to be an important aspect.

Ten years after the Internet revolution are we standing on the brink of another revolution: networked embedded systems that connect the physical world with the computers, enabling new applications ranging from environmental monitoring and wildlife tracking to improvements in health care and medicine. 98% of all microprocessors sold today are used in embedded systems. Those systems have much smaller amounts of memory than PC computers. An embedded system may have as little has a few hundred bytes of memory, which makes programming them a challenge. This thesis focus on three topics regarding programming memory-constrained networked embedded systems: the TCP/IP for memory-constrained networked embedded systems, simplifying event-driven programming of memory-constrained systems, and dynamic loading of program modules in my Contiki operating system for memory-constrained systems. I show that the TCP/IP protocol stack can, contrary to previous belief, be used in memory-constrained embedded systems by implementing two small TCP/IP protocol stacks, lwIP and uIP. I present a novel programming mechanism called protothreads that I show significantly reduce the complexity of event-driven programming for memory-constrained systems. Protothreads provide a conditional blocked wait mechanism on top of event-driven systems with a much smaller memory overhead than full multithreading; each protothread requires only two bytes of memory. I show that dynamic linking of native code in standard ELF object code format is doable and feasible for wireless sensor networks by implementing a dynamic linker in the Contiki operating system. The results show that the energy overhead of dynamic linking of ELF files mainly is due to the ELF file format and not due to the dynamic linking mechanism as such. The impact of the research in this thesis has been and continues to be large. The software I have developed as part of this thesis is currently used by hundreds of companies in embedded devices in such diverse systems as car engines and satellites. The papers in this thesis are included as required reading in advanced courses on networked embedded systems and wireless sensor networks. / Contiki / uIP / Protothreads

We investigate whether and to what extent the adoption of an intellectual property box increases innovative activity and the extent to which different types of firms benefit financially. We examine the adoption of the intellectual property box in Belgium because it allows us to cleanly identify the impact on innovative activity and effective tax rates. Our results indicate an overall increase in innovative activity as proxied by patent applications, grants, and highly-skilled employment, at the expense of patent quality. We also provide evidence that firms with patents on average enjoy 7.2% to 7.9% lower effective tax rates, with the greatest financial benefits accruing to multinational firms compared to domestic firms. Within multinational firms, those without income shifting opportunities appear to benefit more than other multinationals with income shifting opportunities. / Series: WU International Taxation Research Paper Series

O objetivo deste trabalho é construir um modelo do tráfego de redes de computadores e aplicar a este modelo o conjunto de técnicas de Controle Estatístico de Processo (CEP) de forma a viabilizar ações preventivas sobre a rede. Trabalhou-se com a hipótese de que é possível determinar estatisticamente o comportamento da rede em um dado número de variáveis de interesse. O modelo, representado em sua forma final por um conjunto de variáveis que descrevem o tráfego modelado, foi construído a partir da observação da rede local do Instituto de Física de São Carlos (IFSC). Recolheram-se aproximadamente 10 milhões de registros, pelo software NeTraMet, classificados em fluxos e posteriormente processados por aplicativos criados especificamente para esta finalidade. Dado que o CEP pressupõe a normalidade dos dados, cuidou-se de verificar formalmente esta propriedade nas amostras colhidas, pela aplicação do teste qui-quadrado aos valores individuais. Em conformidade a referências da literatura, fez-se o mesmo em relação aos valores médios das amostras. Em ambas as situações, comprovou-se a não-normalidade das distribuições. Investigaram-se os efeitos desta constatação no CEP e desenvolveu-se uma nova metodologia de cálculo dos limites de controle, fundamentada nos trabalhos do matemático russo Pafnuty Lvovich Chebyshev (1821 – 1894), sobre teoria das probabilidades. Adaptou-se, pois, o CEP às condições reais observadas, expandindo-se a possibilidade de seu uso em distribuições não-normais. Aplicou-se o CEP devidamente adaptado aos dados da rede do IFSC, gerando-se um estudo de caso. Verificou-se que o modelo capta adeqüadamente a realidade da rede. Sua utilidade foi ilustrada pela efetiva detecção de situações anômalas. As cartas CEP geradas sugeriram a inserção de um ajuste de sensibilidade nos controles, deixado para futuros trabalhos. Os objetivos da pesquisa foram atingidos pela criação de um modelo original e comprovação da hipótese inicialmente apresentada. Foram excedidas as expectativas pela obtenção de resultados importantes e inesperados e pelo desenvolvimento de uma nova metodologia de cálculo para um ferramental já consagrado. / This work aims the development of a computer network traffic model, and subject it to the set of Statistical Process Control (SPC) techniques, in order to allow preventive actions to the network. The hypothesis of a possible statistical determination of the network behavior, at a certain number of specific parameters, was analysed. The model was developed based on local observations of the Instituto de Física de São Carlos (IFSC) network, and the final version of the model was represented by a set of parameters that describes its traffic. The NeTraMet software collected around 10 million reports, classified as flows and later on processed by specific applications. Since the SPC assumes the normality of the data, a chi-square test was applied to individual values, to confirm this characteristic in the samples collected. The same was done to the average values of the samples, as recommended by the literature. Both tests showed the no-normality of the distributions. This effect on SPC was studied, and then a new methodology to calculate the control limits was developed, based on the work of the Russian mathematician Pafnuty Lvovich Chebyshev (1821-1894), about the probability theory. SPC was adapted to real conditions making its use in no-normal distributions possible. A well-adapted SPC was applied to the IFSC network data, resulting in a study case, and it could be verified that the model properly captured the reality of the network. Its use was demonstrated by the effective detection of anomalous situations. The SPC charts generated suggested an adjustment of the control sensibility, what was left for future research. The development of an original model and the confirmation of the hypothesis above, make clear that the goals of this work were achieved. In fact, important and unexpected results surpassed the expectations of this study, as much as the development of a new calculation methodology for a well-stated tool.

La elaboración de este documento parte de dos premisas claramente visibles en el entorno sobre el cual nos desarrollamos. La primera de ellas tiene su origen en la sociedad, se desenvuelve negativamente al interior de las instancias que la componen y actúa de tal manera, que cualquier estudio que busque demostrar sus consecuencias adquiere casi de inmediato un cierto nivel de insignificancia frente a lo cotidianamente experimentado. La segunda premisa parte de un fenómeno también social y que ha adquirido carácter masivo con el transcurrir de las últimas décadas; su expansión y desarrollo, por el contrario, son auspiciosos dado que sus objetivos están orientados a resolver problemas. / Tesis

El desarrollo de las telecomunicaciones en los últimos años se viene orientando a la aplicación de nuevas tecnologías de alta capacidad de transmisión, dirigidas a mejorar la calidad y a aumentar la cantidad de servicios brindados tales como telefonía, multimedia, videoconferencia, Internet, entre otros. Las cuales destacan las inalámbricas como Wi-Fi y WiMAX por su fácil instalación y bajo costo. Surge así, la posibilidad de aplicar dichas tecnologías a la demanda de comunicaciones que requieren los habitantes de un lugar ausente de ellas. Por ello, el presente proyecto de tesis consiste en proponer el diseño de una plataforma de servicios de telecomunicaciones: telefonía fija, telefonía pública e Internet al sitio arqueológico y turístico de Caral, el cual no cuenta con tales servicios y los demanda cada día más debido al creciente número de turistas que atrae, trayendo como consecuencia brindarles las facilidades de comunicación en todo momento, y así activar económicamente a su población, a los establecimientos turísticos y a las actividades comerciales de la zona. De esta manera, se propone la tecnología de telecomunicaciones más adecuada para cubrir esta demanda y lograr su conectividad a todo el mundo. Este trabajo de tesis se divide en 4 capítulos: el primer capítulo consiste en el estudio de la demanda demográfica de turistas y del tráfico que requerirán los servicios de telecomunicaciones en el centro turístico de Caral. En el segundo capítulo, se analizan las mejores alternativas tecnológicas inalámbricas para la plataforma de acceso a red de Caral, haciendo un estudio del estándar WiMAX y una comparación con el estándar Wi-Fi. En el tercer capítulo, se desarrolla la ingeniería del proyecto, es decir, el diseño de la red total a implementar en el centro arqueológico de Caral, eligiendo la tecnología a usar, la marca y los equipos de telecomunicaciones más adecuados a la misma. Por último, el cuarto capítulo, consiste en un análisis de los costos de inversión, operación y mantenimiento de la red puesta ya en marcha, brindando los servicios de telecomunicaciones y revisando a la vez la factibilidad y tiempo de recuperación de la inversión que implicó hacer este proyecto completo. Finalmente, se presentan las conclusiones de este proyecto, producto del desarrollo de la presente tesis. / Tesis

En este trabajo se explica cómo funciona la transferencia de datos y qué políticas de control siguen los protocolos Aloha Puro y el Aloha Ranurado para evitar y gestionar las colisiones. Se realiza la programación de un modelo de cadenas de Markov para cada uno de los protocolos y con ayuda del programa SCILAB se simulan los rendimientos que éstos en diferentes escenarios. / Tesis