933 resultados para terrorist attacks


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We present a multipartite protocol in a counterfactual paradigm. In counterfactual quantum cryptography, secure information is transmitted between two spatially separated parties even when there is no physical travel of particles transferring the information between them. We propose here a tripartite counterfactual quantum protocol for the task of certificate authorization. Here a trusted third party, Alice, authenticates an entity Bob (e.g., a bank) that a client Charlie wishes to securely transact with. The protocol is counterfactual with respect to either Bob or Charlie. We prove its security against a general incoherent attack, where Eve attacks single particles.

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User authentication is essential for accessing computing resources, network resources, email accounts, online portals etc. To authenticate a user, system stores user credentials (user id and password pair) in system. It has been an interested field problem to discover user password from a system and similarly protecting them against any such possible attack. In this work we show that passwords are still vulnerable to hash chain based and efficient dictionary attacks. Human generated passwords use some identifiable patterns. We have analysed a sample of 19 million passwords, of different lengths, available online and studied the distribution of the symbols in the password strings. We show that the distribution of symbols in user passwords is affected by the native language of the user. From symbol distributions we can build smart and efficient dictionaries, which are smaller in size and their coverage of plausible passwords from Key-space is large. These smart dictionaries make dictionary based attacks practical.

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Drawing inspiration from real world interacting systems, we study a system consisting of two networks that exhibit antagonistic and dependent interactions. By antagonistic and dependent interactions we mean that a proportion of functional nodes in a network cause failure of nodes in the other, while failure of nodes in the other results in failure of links in the first. In contrast to interdependent networks, which can exhibit first-order phase transitions, we find that the phase transitions in such networks are continuous. Our analysis shows that, compared to an isolated network, the system is more robust against random attacks. Surprisingly, we observe a region in the parameter space where the giant connected components of both networks start oscillating. Furthermore, we find that for Erdos-Renyi and scale-free networks the system oscillates only when the dependence and antagonism between the two networks are very high. We believe that this study can further our understanding of real world interacting systems.

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In this paper, we propose a new state transition based embedding (STBE) technique for audio watermarking with high fidelity. Furthermore, we propose a new correlation based encoding (CBE) scheme for binary logo image in order to enhance the payload capacity. The result of CBE is also compared with standard run-length encoding (RLE) compression and Huffman schemes. Most of the watermarking algorithms are based on modulating selected transform domain feature of an audio segment in order to embed given watermark bit. In the proposed STBE method instead of modulating feature of each and every segment to embed data, our aim is to retain the default value of this feature for most of the segments. Thus, a high quality of watermarked audio is maintained. Here, the difference between the mean values (Mdiff) of insignificant complex cepstrum transform (CCT) coefficients of down-sampled subsets is selected as a robust feature for embedding. Mdiff values of the frames are changed only when certain conditions are met. Hence, almost 50% of the times, segments are not changed and still STBE can convey watermark information at receiver side. STBE also exhibits a partial restoration feature by which the watermarked audio can be restored partially after extraction of the watermark at detector side. The psychoacoustic model analysis showed that the noise-masking ratio (NMR) of our system is less than -10dB. As amplitude scaling in time domain does not affect selected insignificant CCT coefficients, strong invariance towards amplitude scaling attacks is also proved theoretically. Experimental results reveal that the proposed watermarking scheme maintains high audio quality and are simultaneously robust to general attacks like MP3 compression, amplitude scaling, additive noise, re-quantization, etc.

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The growing number of applications and processing units in modern Multiprocessor Systems-on-Chips (MPSoCs) come along with reduced time to market. Different IP cores can come from different vendors, and their trust levels are also different, but typically they use Network-on-Chip (NoC) as their communication infrastructure. An MPSoC can have multiple Trusted Execution Environments (TEEs). Apart from performance, power, and area research in the field of MPSoC, robust and secure system design is also gaining importance in the research community. To build a secure system, the designer must know beforehand all kinds of attack possibilities for the respective system (MPSoC). In this paper we survey the possible attack scenarios on present-day MPSoCs and investigate a new attack scenario, i.e., router attack targeted toward NoC architecture. We show the validity of this attack by analyzing different present-day NoC architectures and show that they are all vulnerable to this type of attack. By launching a router attack, an attacker can control the whole chip very easily, which makes it a very serious issue. Both routing tables and routing logic-based routers are vulnerable to such attacks. In this paper, we address attacks on routing tables. We propose different monitoring-based countermeasures against routing table-based router attack in an MPSoC having multiple TEEs. Synthesis results show that proposed countermeasures, viz. Runtime-monitor, Restart-monitor, Intermediate manager, and Auditor, occupy areas that are 26.6, 22, 0.2, and 12.2 % of a routing table-based router area. Apart from these, we propose Ejection address checker and Local monitoring module inside a router that cause 3.4 and 10.6 % increase of a router area, respectively. Simulation results are also given, which shows effectiveness of proposed monitoring-based countermeasures.

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Resumen: Hacia el 167 a.C., un joven Polibio, se sorprendía de que Roma hubiera podido afi rmar su poderío en la península, resistir los ataques cartagineses y acabar imponiendo sus leyes en Oriente. Probablemente –explica P. Grimal– en ello también haya infl uido que las costumbres y tradiciones romanas contribuían a asegurar una superioridad sobre el resto de las culturas y hacían de Roma una ciudad única entre todas. La familia y la mujer constituyeron parte fundamental dentro de la consolidación de esa estructura socio política y de ello heredaríamos, especialmente a nivel normativo, una sólida tradición jurídico-romana. Sin embargo, la época imperial representó un grave período de crisis en el cual, tomar esposa, dar hijos a la patria y controlar los patrimonios, se convirtió en una importante reafi rmación moral, jurídica y política para la sociedad de su tiempo. En esta forma, se analizarán brevemente algunos conceptos y leyes relevantes –cuyos ecos volveremos a encontrar refl ejados a lo largo y ancho de la España cristiana medieval– los cuales nos ayudarán a adentrarnos en la cotidianidad de este singular período, sus emancipadas mujeres aristocráticas y el derecho privado.

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En este trabajo se aborda la visión del hombre como persona humana y el respeto que se le debe como tal desde el inicio de su vida en la concepción hasta su fin natural. Los atentados que pueden y podrán cometerse contra la vida constituyen otros tantos atentados también contra la institución familiar, lugar natural del nacimiento y desarrollo de la vida de un nuevo ser humano. El respeto por el hombre en cuanto persona es una de las exigencias que no admiten discusión; de ella dependen la dignidad y también el bienestar y la subsistencia de la Humanidad.

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[Es] En este trabajo se parte de la hipótesis de que los propios contenidos televisivos son fuente de aprendizaje a través de las narraciones televisivas. En concreto, defendemos la idea de que es posible enseñar y aprender valores a través de dichas narraciones. Se sistematizan algunas de las investigaciones que han abordado la relación entre televisión y valores desde una triple dimensión: los propios contenidos; el medio en sí mismo y el lenguaje. Esta revisión nos permite defender que las condenas reiteradas a la televisión, responsabilizándola de la mayoría de los males que sufre la juventud, no pueden apoyarse en los estudios que la psicología ha realizado en las últimas décadas. Entendemos que el telespectador incorpora la información televisiva desde distintos contextos y que la enculturación no es unidireccional. Existe una interacción entre contextos de desarrollo y mensajes. Concretamente nos interesa analizar los valores implícitos y explícitos que subyacen a los contenidos televisivos. Para ello basándonos en el modelo elaborado por Schwartz y Bilsky hemos creado un cuestionario (Val-TV 01) con el fin de clasificar los valores e interpretar las conductas visualizadas en los textos televisivos y relacionarlos con los propios valores de los adolescentes.

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[EN] Panic disorder is a highly prevalent neuropsychiatric disorder that shows co-occurrence with substance abuse. Here, we demonstrate that TrkC, the high-affinity receptor for neurotrophin-3, is a key molecule involved in panic disorder and opiate dependence, using a transgenic mouse model (TgNTRK3). Constitutive TrkC overexpression in TgNTRK3 mice dramatically alters spontaneous firing rates of locus coeruleus (LC) neurons and the response of the noradrenergic system to chronic opiate exposure, possibly related to the altered regulation of neurotrophic peptides observed. Notably, TgNTRK3 LC neurons showed an increased firing rate in saline-treated conditions and profound abnormalities in their response to met5-enkephalin. Behaviorally, chronic morphine administration induced a significantly increased withdrawal syndrome in TgNTRK3 mice. In conclusion, we show here that the NT-3/TrkC system is an important regulator of neuronal firing in LC and could contribute to the adaptations of the noradrenergic system in response to chronic opiate exposure. Moreover, our results indicate that TrkC is involved in the molecular and cellular changes in noradrenergic neurons underlying both panic attacks and opiate dependence and support a functional endogenous opioid deficit in panic disorder patients.

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Elasmobranchs are vital and valuable components of the marine biota. From an ecological perspective they occupy the role of top predators within marine food webs, providing a regulatory control that helps balance the ecosystem. From an evolutionary perspective, this group represents an early divergence along the vertebrate line that produced many unusual, but highly successful, adaptations in function and form. From man's perspective, elasmobranchs have been considered both an unavoidable nuisance, and an exploitable fishery resource. A few of the large shark species have earned a dubious notoriety because of sporadic attacks on humans that occur in coastal areas each year worldwide; the hysteria surrounding an encounter with a shark can be costly to the tourist industry. More importantly, elasmobranchs are often considered a detriment to commercial fishing operations; they cause significant economic damage to catches and fishing gear. On the other hand, consumer attitudes have changed concerning many previously unpopular food fishes, including elasmobranchs, and this group of fishes has been increasingly used by both recreational and commercial fishing interests. Many elasmobranchs have become a popular target of recreational fishermen for food and sport because of their abundance, size, and availability in coastal waters. Similarly, commercial fisheries for elasmobranchs have developed or expanded from an increased demand for elasmobranch food products. (PDF file contains 108 pages.)

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On October 24, 1871, a massacre of eighteen Chinese in Los Angeles brought the small southern California settlement into the national spotlight. Within a few days, news of this “night of horrors” was reported in newspapers across the country. This massacre has been cited in Asian American narratives as the first documented outbreak of ethnic violence against a Chinese community in the United States. This is ironic because Los Angeles’ small population has generally placed it on the periphery in historical studies of the California anti-Chinese movement. Because the massacre predated Los Angeles’ organized Chinese exclusion movements of the late 1870s, it has often been erroneously dismissed as an aberration in the history of the city.

The violence of 1871 was an outburst highlighting existing community tensions that would become part of public debate by decade’s close. The purpose of this study is to insert the massacre into a broader context of anti-Chinese sentiments, legal discrimination, and dehumanization in nineteenth century Los Angeles. While a second incident of widespread anti-Chinese violence never occurred, brutal attacks directed at Chinese small businessmen and others highlighted continued community conflict. Similarly, economic rivalries and concerns over Chinese prostitution that underlay the 1871 massacre were manifest in later campaigns of economic discrimination and vice suppression that sought to minimize Chinese influence within municipal limits. An analysis of the massacre in terms of anti-Chinese legal, social and economic strategies in nineteenth-century Los Angeles will elucidate these important continuities.

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[ES]Este Trabajo de Fin de Grado consiste en diseñar y desarrollar una solución de resilient communications para su uso en entornos de movilidad, en concreto, en entornos vehiculares. Se diseñara una solución que consiste en añadir soporte de múltiples vías de comunicación entre dos extremos para el protocolo de movilidad HIP. Este trabajo consiste en buscar una solución de resilient communications, ya que buscamos como objetivo principal aumentar la disponibilidad del sistema de comunicaciones, es decir, aumentar aspectos tales como la tolerancia a fallos y contra ataques de seguridad, concretamente contra ataques contra la disponibilidad.

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There is, in nature, as well as in the aquarium, a parasitic disease known as 'mousse' and which attacks predominantly fish. It is caused by Phycomycete fungi, genus Saprolegnia. The fungus causes external lesions and covers the fish with a thick white layer from whence comes the name 'mousse', commonly attributed to the disease, for which the scientific name is Saprolegnia. This article provides an overview of Saprolegnia infections on fish in nature and aquaria and then discusses symptomology of Saprolegnia in the mirror caro and t roach in more detail.

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Esta tese se insere no conjunto de pesquisas que procura entender como funcionam as eleições no Brasil. Especificamente, o objetivo é investigar a propaganda negativa durante as eleições presidenciais. Para tal foram desenvolvidos cinco capítulos. O primeiro situa o leitor no debate normativo sobre o papel da propaganda negativa para a democracia eleitoral. Nele, é debatida a importância dos ataques em uma série de circunstâncias, como mobilização política, ambiente informacional e decisão do voto. O segundo capítulo constitui ampla análise do conteúdo da propaganda negativa exibida no âmbito do Horário Gratuito de Propaganda Eleitoral durante as eleições presidenciais de 1989, 1994, 1998, 2002, 2006 e 2010, primeiro e segundo turnos. A metodologia seguiu as orientações formuladas por Figueiredo et all. (1998), mas adaptadas para as especificidades da propaganda negativa. Neste objetivo, tendências interessantes foram descobertas, a mais interessante, sem dúvida, é o baixo índice de ataques ocorrido entre os candidatos. O terceiro busca investigar o uso estratégico das inserções durante as campanhas presidenciais. Debato o caráter regulamentado do modelo brasileiro de propaganda. Ainda assim, aponto estratégias divergentes no uso estratégico das inserções negativas, sendo o horário noturno o lócus predominante dos ataques. O quarto capítulo procura criar um modelo de campanha negativa com base na teoria dos jogos. No modelo, procuro responder às seguintes questões: quem ataca quem, quando e por quê? Argumento que a propaganda negativa é o último recurso utilizado pelos candidatos na conquista por votos. Ela tem como propósito central alterar a tendência do adversário. Por essa razão, é utilizada principalmente por candidatos em situações de desvantagem nos índices de intenção de voto. O quinto e último capítulo desenvolve modelo estatístico para medir o impacto da propaganda negativa nos índices de intenção de voto.

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A Neuromielite Óptica (NMO), anteriormente considerada como um subtipo de Esclerose Múltipla, é uma doença autoimune, inflamatória do sistema nervoso central, na qual o sistema imune ataca a mielina dos neurônios localizados nos nervos ópticos e medula espinhal, produzindo, então, mielite e neurite óptica simultânea ou sequenciais. A patogênese da neuromielite óptica é influenciada pela combinação de fatores genéticos e ambientais, incluindo agentes infecciosos. Diferentes doenças infecciosas podem tanto desencadear como exacerbar a autoimunidade. Portanto, o objetivo do presente estudo foi de analisar a responsividade imune in vitro a Escherichia coli, Staphylococcus aureus e Candida albicans em pacientes com NMO recorrente-remitente, e a correlacionar ao nível de incapacidade neurológica. Nesse contexto, a extensão da linfoproliferação e perfil de citocinas em resposta a S. aureus e C. albicans, em culturas de células mononucleares do sangue periférico (CMSP) foram similares entre pacientes com NMO e indivíduos saudáveis. Entretanto, maior proliferação de células T associada à elevada liberação de IL-1β, IL-6 e IL-17 foi observada em culturas de células derivadas de pacientes com NMO quando estimuladas com E. coli. Ademais, nessas culturas, a produção de IL-10 foi significativamente menor quando comparada ao grupo controle. Ensaios conduzidos em culturas de CMSP depletadas de diferentes subtipos de linfócitos demonstraram que, enquanto células T CD4+ e T CD8+ produzem IL-6 em resposta a E. coli, a produção de IL-17 foi praticamente restrita às células T CD4+. Os níveis de IL-6 e IL-17 in vitro induzidos por E. coli foram correlacionados positivamente às incapacidades neurológicas. Essa maior tendência a produzir citocinas relacionadas ao perfil Th17 foi diretamente associada aos níveis de IL-23 produzidos por monócitos ativados com LPS. De modo interessante, níveis elevados de LPS foram quantificados no plasma de pacientes com NMO e estes foram correlacionados aos níveis plasmáticos de IL-6. Em conclusão, nossos resultados sugerem que uma maior responsividade a E. coli poderia estar envolvida na patogênese da NMO. Esse tipo de investigação é muito importante pois inibidores da ligação ou sinalização do TLR poderiam ser considerados terapias com grande potencial como adjuvantes no tratamento de pacientes com NMO.