As wireless communication mediums develop and Dynamic Spectrum Access (DSA) is implemented as a means to increase capacity on a limited spectrum, the threat of reactive interference becomes real. The motivation for this thesis is to address this problem by suggesting a mechanism which could be used in these spectrally harsh DSA environments. Overcoming certain types of interference in DSA environments requires unique approaches to transmitting and receiving data. This thesis discusses a decoy-based approach to mitigate conditions in which interference reacts to the spectral movement of the transmitting DSA radio as it hops around the frequency spectrum. Specifically using a polyphase channelizer, multiple replicas of the information signal are simultaneously transmitted at separate frequencies to lure reactive interference away from the main source of transmission. Using either serial or parallel transmission (splitting the signal in time or splitting the signal's energy) with the decoy signals and the original signal can either maximize data throughput in a minimal-interference environment or can add necessary robustness in the presence of multiple sources of reactive interference. This decoy-based approach is verified with network simulation. An event-based simulator written in C++ was used to define the capacity or maximum throughput. Configuration files loaded with the necessary presets are used to run three network simulation scenarios: First Responder, Military Patrol, and Airborne Network. / Master of Science

INTRODUÇÃO: O BKPyV está associado à inflamação e perda da função do enxerto em pacientes transplantados renais. Nos pacientes transplantados renais, aproximadamente 40% dos receptores desenvolvem viruria pelo BKPyV em até 3 meses e 20% desenvolvem viremia em até 1 ano pós-transplante. Os pacientes que desenvolvem viremia têm o risco de evolução para nefropatia associada ao BKPyV (NABKPyV), com prevalência em torno de 1 a 10%, e evolução para perda do enxerto renal bastante variável, de 0 a 100%, dependendo dos estudos e das intervenções realizadas. Embora a vigilância de replicação do BKPyV seja recomendada, existem diferenças de metodologia e periodicidade entre as recomendações publicadas. Adicionalmente, tem sido discutida a importância do cut-off de viremia para o manejo clínico desses pacientes na prevenção de evolução para nefropatia. Os objetivos primários deste estudo foram determinar a prevalência de decoy cell na urina, viremia e viremia sustentada pelo BKPyV e NABKPyV, nos receptores de transplante renal do Serviço de Transplante Renal do HCFMUSP, e os possíveis fatores de risco associados à presença a viremia sustentada pelo BKPyV e NABKPyV. MÉTODOS: Trata-se de um estudo de coorte prospectivo no qual foram incluídos todos os receptores e os doadores de transplante renal intervivos submetidos a transplante de agosto de 2010 a dezembro de 2011. Todos os participantes foram avaliados no momento imediato pré-transplante e os receptores foram monitorados para detecção de viremia de BKPyV e desenvolvimento de NABKPyV durante o período de até 2 anos pós-transplante. Os receptores colheram amostras de urina mensalmente, durante o primeiro ano, e a cada 3 meses durante o segundo ano pós-transplante para a pesquisa de viruria (realizada por decoy cell e/ou q-PCR). A detecção de viruria indicava o início de monitorização mensal de viremia por q-PCR, viremia era mantida até obtenção de três amostras de viremia negativas consecutivas. A detecção da primeira viremia positiva deveria ser confirmada por uma segunda amostra colhida após intervalo de duas semanas; se o exame repetido confirmasse a viremia positiva, os pacientes eram submetidos à biópsia renal percutânea para investigação de NABKPyV. RESULTADOS: No período do estudo foram realizados 326 transplantes e foram incluídos 246 pacientes. A prevalência de viruria foi de 36,9%, a de viremia 22,3% e a de nefropatia 3,2%. O tempo médio entre o transplante e a viruria positiva pela decoy cell foi de 7,2 meses, entre o transplante e a viremia positiva de 7,6 meses, e entre o transplante e o diagnóstico de NABKPyV de 8,5 meses. O único fator de risco encontrado para viremia sustentada e para nefropatia foi gênero masculino. O valor de cut-off de viremia que melhor discrimina a evolução para NABKPyV foi 44.955 cópias/mL. CONCLUSÕES: As prevalências de viruria, viremia e nefropatia foram semelhantes às reportadas na literatura. O gênero masculino foi o único fato de risco encontrado para viremia sustentada e nefropatia. O valor de cut-off de viremia que melhor discrimina o risco de evolução para nefropatia foi maior que o valor usualmente recomendado pela literatura, que é de 10.000 cópias/mL / INTRODUCTION: BKPyV is associated with inflammation and loss of graft function in kidney transplant patients. In kidney transplantation, approximately 35-47% of recipients develop viruria by BKPyV within 3 months post-transplantation, and 20% develop viremia within one year post-transplantation. Patients who develop viremia are at risk of progression to BKPyV-associated nephropathy (BKPyVAN), with prevalence around 1 to 10%, and a quite variable prevalence of progression to kidney graft loss, ranging from 0 to 100%, depending on the studies and the interventions. Although BKPyV surveillance is recommended, there are differences in methodology and frequency between published recommendations. In addition, the importance of viremia cutoff for clinical management of these patients in the prevention of progression for nephropathy has been discussed. The objectives of this study were to determine the prevalence of decoy cell in urine, BKPyV viremia, BKPyV sustained viremia, and BKPyVAN, in kidney transplant recipients of HCFMUSP Kidney Transplant Service. Additionally, the aim was to determine the possible risk factors associated with the presence of BKPyV sustained viremia and BKPyVAN. METHODS: This is a prospective cohort study. From August 2010 to December 2011, all recipients and donors of kidney transplant who underwent transplantation were enrolled. All participants were evaluated at immediate pre-transplant and recipients were monitored for detection of BKPyV viremia and development of BKPyVAN for up to two years post-transplantation. All recipients collected urine samples monthly during the first year and every three months during the second year post-transplant for viruria screening (performed by decoy cell and/or q-PCR). Viruria detection indicated the initiation of monthly viremia monitoring by q-PCR. Viremia was maintained until three consecutive negative viremia samples were obtained. The detection of the first positive viremia should be confirmed by a second sample collected after a two-week interval. If repeated examination confirmed positive viremia, the patients underwent percutaneous kidney biopsy to investigate BKPyVAN. RESULTS: During the study period, 326 transplants were performed and 246 patients were included. The prevalence of viruria, viremia, and nephropathy was, respectively, 36.9%, 22.3%, and 3.2%. The mean time between transplantation and positive viruria by decoy cell was 7.2 months, between transplantation and positive viremia was 7.6 months, and between transplantation and diagnosis of BKPyVAN was 8.5 months. The only risk factor for sustained viremia and nephropathy was male. Viremia cutoff value that best discriminates the progression to BKPyVAN was 44,955 copies/mL. CONCLUSIONS: The prevalence of viruria, viremia, and nephropathy were similar to those reported in the literature. Male was the only risk factor found for sustained viremia and nephropathy. Viremia cutoff value that best discriminates the risk of progression to nephropathy was greater than the value usually recommended in the literature, which is 10,000 copies/mL

INTRODUÇÃO: O BKPyV está associado à inflamação e perda da função do enxerto em pacientes transplantados renais. Nos pacientes transplantados renais, aproximadamente 40% dos receptores desenvolvem viruria pelo BKPyV em até 3 meses e 20% desenvolvem viremia em até 1 ano pós-transplante. Os pacientes que desenvolvem viremia têm o risco de evolução para nefropatia associada ao BKPyV (NABKPyV), com prevalência em torno de 1 a 10%, e evolução para perda do enxerto renal bastante variável, de 0 a 100%, dependendo dos estudos e das intervenções realizadas. Embora a vigilância de replicação do BKPyV seja recomendada, existem diferenças de metodologia e periodicidade entre as recomendações publicadas. Adicionalmente, tem sido discutida a importância do cut-off de viremia para o manejo clínico desses pacientes na prevenção de evolução para nefropatia. Os objetivos primários deste estudo foram determinar a prevalência de decoy cell na urina, viremia e viremia sustentada pelo BKPyV e NABKPyV, nos receptores de transplante renal do Serviço de Transplante Renal do HCFMUSP, e os possíveis fatores de risco associados à presença a viremia sustentada pelo BKPyV e NABKPyV. MÉTODOS: Trata-se de um estudo de coorte prospectivo no qual foram incluídos todos os receptores e os doadores de transplante renal intervivos submetidos a transplante de agosto de 2010 a dezembro de 2011. Todos os participantes foram avaliados no momento imediato pré-transplante e os receptores foram monitorados para detecção de viremia de BKPyV e desenvolvimento de NABKPyV durante o período de até 2 anos pós-transplante. Os receptores colheram amostras de urina mensalmente, durante o primeiro ano, e a cada 3 meses durante o segundo ano pós-transplante para a pesquisa de viruria (realizada por decoy cell e/ou q-PCR). A detecção de viruria indicava o início de monitorização mensal de viremia por q-PCR, viremia era mantida até obtenção de três amostras de viremia negativas consecutivas. A detecção da primeira viremia positiva deveria ser confirmada por uma segunda amostra colhida após intervalo de duas semanas; se o exame repetido confirmasse a viremia positiva, os pacientes eram submetidos à biópsia renal percutânea para investigação de NABKPyV. RESULTADOS: No período do estudo foram realizados 326 transplantes e foram incluídos 246 pacientes. A prevalência de viruria foi de 36,9%, a de viremia 22,3% e a de nefropatia 3,2%. O tempo médio entre o transplante e a viruria positiva pela decoy cell foi de 7,2 meses, entre o transplante e a viremia positiva de 7,6 meses, e entre o transplante e o diagnóstico de NABKPyV de 8,5 meses. O único fator de risco encontrado para viremia sustentada e para nefropatia foi gênero masculino. O valor de cut-off de viremia que melhor discrimina a evolução para NABKPyV foi 44.955 cópias/mL. CONCLUSÕES: As prevalências de viruria, viremia e nefropatia foram semelhantes às reportadas na literatura. O gênero masculino foi o único fato de risco encontrado para viremia sustentada e nefropatia. O valor de cut-off de viremia que melhor discrimina o risco de evolução para nefropatia foi maior que o valor usualmente recomendado pela literatura, que é de 10.000 cópias/mL / INTRODUCTION: BKPyV is associated with inflammation and loss of graft function in kidney transplant patients. In kidney transplantation, approximately 35-47% of recipients develop viruria by BKPyV within 3 months post-transplantation, and 20% develop viremia within one year post-transplantation. Patients who develop viremia are at risk of progression to BKPyV-associated nephropathy (BKPyVAN), with prevalence around 1 to 10%, and a quite variable prevalence of progression to kidney graft loss, ranging from 0 to 100%, depending on the studies and the interventions. Although BKPyV surveillance is recommended, there are differences in methodology and frequency between published recommendations. In addition, the importance of viremia cutoff for clinical management of these patients in the prevention of progression for nephropathy has been discussed. The objectives of this study were to determine the prevalence of decoy cell in urine, BKPyV viremia, BKPyV sustained viremia, and BKPyVAN, in kidney transplant recipients of HCFMUSP Kidney Transplant Service. Additionally, the aim was to determine the possible risk factors associated with the presence of BKPyV sustained viremia and BKPyVAN. METHODS: This is a prospective cohort study. From August 2010 to December 2011, all recipients and donors of kidney transplant who underwent transplantation were enrolled. All participants were evaluated at immediate pre-transplant and recipients were monitored for detection of BKPyV viremia and development of BKPyVAN for up to two years post-transplantation. All recipients collected urine samples monthly during the first year and every three months during the second year post-transplant for viruria screening (performed by decoy cell and/or q-PCR). Viruria detection indicated the initiation of monthly viremia monitoring by q-PCR. Viremia was maintained until three consecutive negative viremia samples were obtained. The detection of the first positive viremia should be confirmed by a second sample collected after a two-week interval. If repeated examination confirmed positive viremia, the patients underwent percutaneous kidney biopsy to investigate BKPyVAN. RESULTS: During the study period, 326 transplants were performed and 246 patients were included. The prevalence of viruria, viremia, and nephropathy was, respectively, 36.9%, 22.3%, and 3.2%. The mean time between transplantation and positive viruria by decoy cell was 7.2 months, between transplantation and positive viremia was 7.6 months, and between transplantation and diagnosis of BKPyVAN was 8.5 months. The only risk factor for sustained viremia and nephropathy was male. Viremia cutoff value that best discriminates the progression to BKPyVAN was 44,955 copies/mL. CONCLUSIONS: The prevalence of viruria, viremia, and nephropathy were similar to those reported in the literature. Male was the only risk factor found for sustained viremia and nephropathy. Viremia cutoff value that best discriminates the risk of progression to nephropathy was greater than the value usually recommended in the literature, which is 10,000 copies/mL

Influenza is a severe disease in humans and animals, causing upwards of 40,000 deaths every year in America alone. Influenza A virus (IAV) also causes periodic pandemics every 10 to 50 years, killing millions of people. Despite this, very few effective therapies are available. All strains of IAV are prone to developing resistance to antibodies due to the high mutation rate in the viral genome. Because of this mutation rate, a yearly vaccine must be generated before every flu season, and efficacy varies year to year. IAV has also mutated to escape several of the clinically-approved small molecule inhibitors. A therapeutic agent that targets a highly conserved region of the virus could bypass resistance and also be effective against multiple strains of IAV. IAV attachment is mediated by many individually weak hemagglutinin–sialic acid interactions that all together make a strong attachment to a host cell. Polymerized sialic acid analogs can recreate these interactions and block infection. However, they are not ideal therapeutics due to solubility issues and in vivo toxicity. We used liposomes as a novel means for delivery of the sialic acid-containing glycan, sialylneolacto-N-tetraose c (LSTc). LSTcbearing decoy liposomes form multivalent, polymer-like interactions with IAV. Decoy liposomes competitively bind IAV in hemagglutination inhibition assays and inhibit infection of target cells in a dose-dependent manner. LSTc decoy liposomes co-localize with IAV, while control liposomes do not. Inhibition is specific, as inhibition of Sendai virus and respiratory syncytial virus is not observed. In contrast, monovalent LSTc does not bind IAV or inhibit infectivity. LSTc decoy liposomes prevent the spread of IAV during multiple rounds of replication in vitro and extend survival of mice challenged with a lethal dose of virus. Considering the conservation of the hemagglutinin binding pocket and the ability of decoy liposomes to form high-avidity interactions with IAV hemagglutinin, our decoy liposomes have potential as a new therapeutic agent against emerging strains.

Carolina Wrens, Thryothorus ludovicianus, are permanent residents throughout their range. They form pair bonds at a young age, maintain these bonds for multiple years, and defend feeding/breeding territories year round. Male Carolina Wrens use songs in territorial defense and have been shown to countersing regularly to both neighbors and intruders. They use various song characteristics to determine the location of another bird and whether its territory has been invaded. Wrens often approach playbacks silently in apparent searching behavior. In some cases, birds will investigate the playback but fail to countersing. I wanted to determine whether or not wrens would respond more strongly during playbacks with a decoy. In addition, the experiment was conducted during breeding and nonbreeding periods to compare responses across seasons. The findings show that wrens respond more aggressively to playbacks with a decoy and to playbacks conducted during the breeding season.

This work presents our efforts on preventing the web bots to illegitimately access web resources. As the first technique, we present SEMAGE (SEmantically MAtching imaGEs), a new image-based CAPTCHA that capitalizes on the human ability to define and comprehend image content and to establish semantic relationships between them. As the second technique, we present NOID - a "NOn-Intrusive Web Bot Defense system" that aims at creating a three tiered defence system against web automation programs or web bots. NOID is a server side technique and prevents the web bots from accessing web resources by inherently hiding the HTML elements of interest by randomization and obfuscation in the HTML responses. A SEMAGE challenge asks a user to select semantically related images from a given image set. SEMAGE has a two-factor design where in order to pass a challenge the user is required to figure out the content of each image and then understand and identify semantic relationship between a subset of them. Most of the current state-of-the-art image-based systems like Assira only require the user to solve the first level, i.e., image recognition. Utilizing the semantic correlation between images to create more secure and user-friendly challenges makes SEMAGE novel. SEMAGE does not suffer from limitations of traditional image-based approaches such as lacking customization and adaptability. SEMAGE unlike the current Text based systems is also very user friendly with a high fun factor. We conduct a first of its kind large-scale user study involving 174 users to gauge and compare accuracy and usability of SEMAGE with existing state-of-the-art CAPTCHA systems like reCAPTCHA (text-based) and Asirra (image-based). The user study further reinstates our points and shows that users achieve high accuracy using our system and consider our system to be fun and easy. We also design a novel server-side and non-intrusive web bot defense system, NOID, to prevent web bots from accessing web resources by inherently hiding and randomizing HTML elements. Specifically, to prevent web bots uniquely identifying HTML elements for later automation, NOID randomizes name/id parameter values of essential HTML elements such as "input textbox", "textarea" and "submit button" in each HTTP form page. In addition, to prevent powerful web bots from identifying special user-action HTML elements by analyzing the content of their accompanied "label text" HTML tags, we enhance NOID by adding a component, Label Concealer, which hides label indicators by replacing "label text" HTML tags with randomized images. To further prevent more powerful web bots identifying HTML elements by recognizing their relative positions or surrounding elements in the web pages, we enhance NOID by adding another component, Element Trapper, which obfuscates important HTML elements' surroundings by adding decoy elements without compromising usability. We evaluate NOID against five powerful state-of-the-art web bots including XRumer, SENuke, Magic Submitter, Comment Blaster, and UWCS on several popular open source web platforms including phpBB, Simple Machine Forums (SMF), and Wordpress. According to our evaluation, NOID can prevent all these web bots automatically sending spam on these web platforms with reasonable overhead.

We build a variety of customer booking choice models for a major airline that operates in a very competitive origin-destination market. Some of the models are aimed at incorporating unobserved heterogeneous customer preferences for different departure times. The estimation results show that including these factors into choice models dramatically affects price sensitivity estimates, and therefore matters. We present a stochastic trust region algorithm for estimating ML-type models that involve high-dimensional integrals. The algorithm embeds two sampling processes: (i) a data sampling process and (ii) a Monte Carlo sampling process, and the algorithm dynamically controls sample sizes based on the magnitude of the errors incurred due to the two sampling processes. The first-order convergence is proved based on generalized uniform law of large numbers theories for both the average log-likelihood function and its gradient. The efficiency of the algorithm is tested with real data and compared with existing algorithms. We also study how a specific behavioral phenomenon, called the decoy effect, affects the decisions of sellers in product assortment competition in a duopoly. We propose a discrete choice model to capture decoy effects, and we provide a complete characterization of the Nash equilibria and their dependence on choice model parameters. For the cases in which there are multiple equilibria, we consider dynamical systems models of the sellers responding to their competitors using Cournot adjustment or fictitious play to study the evolution of the assortment competition and the stability of the equilibria. We provide a simple geometric characterization of the dynamics of fictitious play for 2×2 games that is more complete than previous characterizations.

Undersökningens syfte är att pröva om en mindre stat kan nyttja sig av vilseledning för att minska åverkan från en motståndare som nyttjar sig av Wardens systemteori. Undersökningen fokuserar främst på att vilseleda en motståndares målinhämtning innan ett angrepp. Undersökningen ger förslag på ett antal sätt att genomföra defensiv vilseledning, både innan ett angrepp och under påbörjat angrepp. För att underlätta för undersökningen tas fiktiva målval ut inom Sverige med stöd av Wardens litteratur och med stöd i viss annan litteratur. En mindre jämförelse mot befintliga sårbarhetsanalyser genomförs. Undersökningen har visat att alla presenterade målval utom ett har viss användning av den defensiva vilseledningen som skildras i uppsatsen. Vidare har undersökningen presenterat en motståndares troliga målval mot Sverige om motståndaren följer Wardens teori. Uppsatsen har också visat på ett antal sårbarheter i Sverige om en motståndare nyttjar Wardens teori. / The purpose of the survey is to test whether a smaller state can use deception to reduce the impact of an opponent who uses Wardens theory regarding the enemy as a system. The survey focuses on an opponent's target acquisition before an attack and the deception that might complicate the target acquisition. The survey presents a number of ways to implement defensive deception, both before and during an attack. To aid the survey a fictitious target acquisition within Sweden has been produced with the support of Wardens literature and with the support of other sources. A comparison is made between the identified vulnerabilities and existing vulnerability reports. The survey has shown that all the presented fictitious targets except one has some use of the defensive deception as presented. Furthermore the survey has presented credible targets in Sweden that an opponent might choose to attack if the opponent makes use of Wardens theory. The survey has shown several vulnerabilities in Sweden if the opponents makes use of Wardens theory.

Au cours de cette thèse, j’ai utilisé des complexes composés d’acides nucléiques, d’un polymère cationique et de liposomes cationiques appelés Lipopolyplexes pour formuler des siRNA (LPRi) et un leurre ADN (LPD) afin inhiber la croissance des cellules 4T1, un modèle murin de carcinome mammaire. Dans une première étude, des injections systémique ou endotrachéale de LPRi avec des siRNA anti-luciférase n’ont pas permis d’inhiber l’expression de la luciférase dans des métastases pulmonaires induites par des cellules 4T1-luciférase. A partir de ces résultats, les LPRi ont été améliorés en ciblant les cellules 4T1 avec le peptide uPA et/ou RGDc ou l’acide folique incorporés aux liposomes selon diverses approches. Les formulations obtenues ont été caractérisées, leur endocytose et l’effet siRNA mesurés in vitro. Cette deuxième partie a permis d’établir que les LPRi décorés avec du folate étaient la meilleure formulation ciblée. Dans une troisième partie, l’inhibition de la prolifération des cellules 4T1 a été recherchée en ciblant le facteur de transcription STAT3. Des LPRi anti-STAT3 ont montré une très bonne efficacité pour inhiber STAT3, mais sans effet antiprolifératif significatif. Des LPD anti-STAT3 ont montré un très bon effet antiprolifératif, celui-ci étant renforcé lorsqu’une co-délivrance siRNA/leurre ADN (LPRiD) a été réalisée. In vivo, un délai de la croissance des tumeurs 4T1 a été observé après co-délivrance siRNA/leurre ADN. Cette thèse a permis de montrer l’efficacité des lipopolyplexes pour la délivrance combinée de siRNA et de leurre ADN dans les cellules tumorales 4T1. Ils indiquent que des études sont cependant nécessaires pour augmenter leur délivrance in vivo dans la tumeur. / During this thesis, I used complexes made with nucleic acids, cationic polymer and cationic liposomes called Lipopolyplexes to formulate siRNA (LPRi) and DNA molecular decoy (LPD) in order to inhibit the growth of 4T1 cells, a murine model of mammary carcinoma. In a first study, systemic or endotracheal injections of LPRi comprising anti-luciferase siRNA did not allow luciferase inhibition in pulmonary metastases induced by 4T1-Luc cells. From these results, LPRi were improved by targeting 4T1 cells using incorporation, by different means, of uPA and/or RGDc peptide or folic acid in liposomes. Resulted formulations were characterized, their internalization and siRNA transfection efficiency were measured in vitro. This second part showed that folate targeting of LPRi was the best formulation. In a third part, proliferation inhibition of 4T1 cells was investigated by targeting the STAT3 transcription factor. Anti-STAT3 siRNA LPRi showed very good efficacy in inhibiting STAT3, but without significant antiproliferative effect. Anti-STAT3 decoy LPD showed a very good antiproliferative effect, the latter being reinforced when co-delivery siRNA/DNA decoy (LPRiD) was performed. In vivo, a growth retardation of 4T1 tumors was observed after co-delivery siRNA/DNA decoy. This thesis demonstrated the effectiveness of lipopolyplexes for combined delivery of siRNA and DNA decoy in the 4T1 tumor cells. Some studies are however required to increase their in vivo delivery into the tumor.

Diploma thesis deals with topic of given phenomena of behavioural economics. Specifically, it deals with endowment effect, decoy effect and paradox of choice. The goal of the thesis is to verify influence of given phenomena of behavioural economics in practice. Research part deals with analysis of the phenomena which influence decision-making in financial or economic issues and causes individual to behave irrationally and not like Homo oeconomicus. In an analytical part are then given phenomena verified by method of quantitative analysis in real market on given company. Quantitative analysis deals predominantly with breakdown of customer reactions on marketing strategies of given company in defined period. Integral part of the thesis is based on executed research draw practical recommendations for examined company.