921 resultados para identity-based cryptosystem
Resumo:
This study focuses on the granite mountain known as Monte Pindo (627 m above sea level) in the Autonomous Community of Galicia (NW Spain). This territory is included in the area classified as “Costa da Morte” in the “Politica de Ordenación Litoral” (POL) (Coastal Planning Policy) for the region of Galicia. This coastal unit, located between “Rías Baixas” and “Cape Fisterra” has great potential for demonstrating geological processes and its geomorphological heritage is characterized by a high degree of geodiversity of granite landforms. The main objective of our work is to assess the geomorphological heritage of the site, thus revealing its wide geodiversity. We shall analyze and highlight: its scientific value, developing an inventory of granite landforms; its educational valuel and its geotouristic potential. It must be ensured that the Administration understands that natural diversity is composed of both geodiversity and biodiversity. Only then will the sustainable management of Monte Pindo become possible by integrating natural and cultural heritage values. The goal is to ensure that Monte Pindo and its immediate surroundings become a geopark with the aim of promoting local development projects based on the conservation and valorization of its geological heritage.
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Background: Gender can influence post-infarction cardiac remodeling. Objective: To evaluate whether gender influences left ventricular (LV) remodeling and integrin-linked kinase (ILK) after myocardial infarction (MI). Methods: Female and male Wistar rats were assigned to one of three groups: sham, moderate MI (size: 20-39% of LV area), and large MI (size: ≥40% of LV area). MI was induced by coronary occlusion, and echocardiographic analysis was performed after six weeks to evaluate MI size as well as LV morphology and function. Real-time RT-PCR and Western blot were used to quantify ILK in the myocardium. Results: MI size was similar between genders. MI resulted in systolic dysfunction and enlargement of end-diastolic as well as end-systolic dimension of LV as a function of necrotic area size in both genders. Female rats with large MI showed a lower diastolic and systolic dilatation than the respective male rats; however, LV dysfunction was similar between genders. Gene and protein levels of ILK were increased in female rats with moderate and large infarctions, but only male rats with large infarctions showed an altered ILK mRNA level. A negative linear correlation was evident between LV dimensions and ILK expression in female rats with large MI. Conclusions: Post-MI ILK expression is altered in a gender-specific manner, and higher ILK levels found in females may be sufficient to improve LV geometry but not LV function.
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Starting from the observation that ghosts are strikingly recurrent and prominent figures in late-twentieth African diasporic literature, this dissertation proposes to account for this presence by exploring its various functions. It argues that, beyond the poetic function the ghost performs as metaphor, it also does cultural, theoretical and political work that is significant to the African diaspora in its dealings with issues of history, memory and identity. Toni Morrison's Beloved (1987) serves as a guide for introducing the many forms, qualities and significations of the ghost, which are then explored and analyzed in four chapters that look at Fred D'Aguiar's Feeding the Ghosts (1998), Gloria Naylor's Mama Day (1988), Paule Marshall's Praisesong for the Widow (1983) and a selection of novels, short stories and poetry by Michelle Cliff. Moving thematically through these texts, the discussion shifts from history through memory to identity as it examines how the ghost trope allows the writers to revisit sites of trauma; revise historical narratives that are constituted and perpetuated by exclusions and invisibilities; creatively and critically repossess a past marked by violence, dislocation and alienation and reclaim the diasporic culture it contributed to shaping; destabilize and deconstruct the hegemonic, normative categories and boundaries that delimit race or sexuality and envision other, less limited and limiting definitions of identity. These diverse and interrelated concerns are identified and theorized as participating in a project of "re-vision," a critical project that constitutes an epistemological as much as a political gesture. The author-based structure allows for a detailed analysis of the texts and highlights the distinctive shapes the ghost takes and the particular concerns it serves to address in each writer's literary and political project. However, using the ghost as a guide into these texts, taken collectively, also throws into relief new connections between them and sheds light on the complex ways in which the interplay of history, memory and identity positions them as products of and contributions to an African diasporic (literary) culture. If it insists on the cultural specificity of African diasporic ghosts, tracing its origins to African cultures and spiritualities, the argument also follows gothic studies' common view that ghosts in literary and cultural productions-like other related figures of the living dead-respond to particular conditions and anxieties. Considering the historical and political context in which the texts under study were produced, the dissertation makes connections between the ghosts in them and African diasporic people's disillusionment with the broken promises of the civil rights movement in the United States and of postcolonial independence in the Caribbean. It reads the texts' theoretical concerns and narrative qualities alongside the contestation of traditional historiography by black and postcolonial studies as well as the broader challenge to conventional notions such as truth, reality, meaning, power or identity by poststructuralism, postcolonialism or queer theory. Drawing on these various theoretical approaches and critical tools to elucidate the ghost's deconstructive power for African diasporic writers' concerns, this work ultimately offers a contribution to "speciality studies," which is currently emerging as a new field of scholarship in cultural theory.
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Based on third order linear sequences, an improvement version of the Diffie-Hellman distribution key scheme and the ElGamal public key cryptosystem scheme are proposed, together with an implementation and computational cost. The security relies on the difficulty of factoring an RSA integer and on the difficulty of computing the discrete logarithm.
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Coastal primary rainforests have suffered damage in Côte d'Ivoire as a result of a lack of protection and urban pressures. Consequently, the highly endemic and critically endangered Wimmer's shrew, Crocidura wimmeri, known only from its type locality, Adiopodoumé, near Abidjan, was considered to have been extinct since 1976. Shrew species assignment is often problematic because of strong phenotypic similarities among many species. The phylogenetic position of C. wimmeri within the African Crocidura species should thus be clarified. In light of its recent rediscovery in the nearby small Banco National Park (34 km2), we investigated the genetic identity of seven specimens of C. wimmeri, based on 1020 bp of the mitochondrial DNA cytochrome b gene compared to other species sampled in the same region and published sequences from GenBank. Crocidura wimmeri formed a well-defined clade, the closest-related species being Crocidura sp., with a distance of 9.3%, a yet unknown species from Taï and Ziama forests. These results thus confirmed the validity of this species. This genetic characterization not only contributes to our knowledge of the evolution of West African shrews, but also may help in the discovery of additional populations of this critically endangered species.
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The present doctoral dissertation is aimed at analyzing how and with what consequences gay father families and their children’s schools negotiate possible differences in the construction of family and gender at home and in the families’ social milieus. This objective fits in with the broader goal of researching how family-school interactons are influenced by the social context such as hegemonic masculinity (Connell, 2002). The thesis is based on qualitative fieldwork carried out with 18 nonheterosexual parent families in Spain, comprising 30 interviews with 44 people. The principal participant group were 14 de novo (adoptive and surrogacy) gay father families with resident preadolescent children. The findings revealed that all the de novo families assumed open communication strategies at school with inclusive consequences: apart from incidental questions and reactions of surprise, the children did not suffer homophobic bullying. The analisis showed that the necessary condition for inclusion was not the open communication but rather illocutionary orientation (Habermas, 1984; Soler & Flecha, 2010), understood as the parents’ sensitivity to the attitudes of their children and schools. The schools received the families in an inclusive manner, which, however, was only receptive and not proactive, therefore some of the families (reconstituted ones), coerced by the social context, got excluded. Gender relations at home were predominantly androgynous, and outside home predominantly traditional, yet the children negotiated this difference with inclusive consequences. They participated in hegemonic collective practices, thus confirming the thesis on the similarity between homo- and heterosexual-parent families (Golombok, 2006). Consistently, also the families’ identity politics was “assimilationist” and non-queer. Admittedly, the analisis showed that such a politics was increased by social expectations. Still, the findings suggest that educational and other family policies should draw on broad agendas of gender and family diversity rather than on the politics of difference and the unique status of LGB families.
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AbstractDigitalization gives to the Internet the power by allowing several virtual representations of reality, including that of identity. We leave an increasingly digital footprint in cyberspace and this situation puts our identity at high risks. Privacy is a right and fundamental social value that could play a key role as a medium to secure digital identities. Identity functionality is increasingly delivered as sets of services, rather than monolithic applications. So, an identity layer in which identity and privacy management services are loosely coupled, publicly hosted and available to on-demand calls could be more realistic and an acceptable situation. Identity and privacy should be interoperable and distributed through the adoption of service-orientation and implementation based on open standards (technical interoperability). Ihe objective of this project is to provide a way to implement interoperable user-centric digital identity-related privacy to respond to the need of distributed nature of federated identity systems. It is recognized that technical initiatives, emerging standards and protocols are not enough to guarantee resolution for the concerns surrounding a multi-facets and complex issue of identity and privacy. For this reason they should be apprehended within a global perspective through an integrated and a multidisciplinary approach. The approach dictates that privacy law, policies, regulations and technologies are to be crafted together from the start, rather than attaching it to digital identity after the fact. Thus, we draw Digital Identity-Related Privacy (DigldeRP) requirements from global, domestic and business-specific privacy policies. The requirements take shape of business interoperability. We suggest a layered implementation framework (DigldeRP framework) in accordance to model-driven architecture (MDA) approach that would help organizations' security team to turn business interoperability into technical interoperability in the form of a set of services that could accommodate Service-Oriented Architecture (SOA): Privacy-as-a-set-of- services (PaaSS) system. DigldeRP Framework will serve as a basis for vital understanding between business management and technical managers on digital identity related privacy initiatives. The layered DigldeRP framework presents five practical layers as an ordered sequence as a basis of DigldeRP project roadmap, however, in practice, there is an iterative process to assure that each layer supports effectively and enforces requirements of the adjacent ones. Each layer is composed by a set of blocks, which determine a roadmap that security team could follow to successfully implement PaaSS. Several blocks' descriptions are based on OMG SoaML modeling language and BPMN processes description. We identified, designed and implemented seven services that form PaaSS and described their consumption. PaaSS Java QEE project), WSDL, and XSD codes are given and explained.
Parts, places, and perspectives : a theory of spatial relations based an mereotopology and convexity
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This thesis suggests to carry on the philosophical work begun in Casati's and Varzi's seminal book Parts and Places, by extending their general reflections on the basic formal structure of spatial representation beyond mereotopology and absolute location to the question of perspectives and perspective-dependent spatial relations. We show how, on the basis of a conceptual analysis of such notions as perspective and direction, a mereotopological theory with convexity can express perspectival spatial relations in a strictly qualitative framework. We start by introducing a particular mereotopological theory, AKGEMT, and argue that it constitutes an adequate core for a theory of spatial relations. Two features of AKGEMT are of particular importance: AKGEMT is an extensional mereotopology, implying that sameness of proper parts is a sufficient and necessary condition for identity, and it allows for (lower- dimensional) boundary elements in its domain of quantification. We then discuss an extension of AKGEMT, AKGEMTS, which results from the addition of a binary segment operator whose interpretation is that of a straight line segment between mereotopological points. Based on existing axiom systems in standard point-set topology, we propose an axiomatic characterisation of the segment operator and show that it is strong enough to sustain complex properties of a convexity predicate and a convex hull operator. We compare our segment-based characterisation of the convex hull to Cohn et al.'s axioms for the convex hull operator, arguing that our notion of convexity is significantly stronger. The discussion of AKGEMTS defines the background theory of spatial representation on which the developments in the second part of this thesis are built. The second part deals with perspectival spatial relations in two-dimensional space, i.e., such relations as those expressed by 'in front of, 'behind', 'to the left/right of, etc., and develops a qualitative formalism for perspectival relations within the framework of AKGEMTS. Two main claims are defended in part 2: That perspectival relations in two-dimensional space are four- place relations of the kind R(x, y, z, w), to be read as x is i?-related to y as z looks at w; and that these four-place structures can be satisfactorily expressed within the qualitative theory AKGEMTS. To defend these two claims, we start by arguing for a unified account of perspectival relations, thus rejecting the traditional distinction between 'relative' and 'intrinsic' perspectival relations. We present a formal theory of perspectival relations in the framework of AKGEMTS, deploying the idea that perspectival relations in two-dimensional space are four-place relations, having a locational and a perspectival part and show how this four-place structure leads to a unified framework of perspectival relations. Finally, we present a philosophical motivation to the idea that perspectival relations are four-place, cashing out the thesis that perspectives are vectorial properties and argue that vectorial properties are relations between spatial entities. Using Fine's notion of "qua objects" for an analysis of points of view, we show at last how our four-place approach to perspectival relations compares to more traditional understandings.
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We argue that attitudes about immigration can be better understood by paying closer attention to the various ways in which national group boundaries are demarcated. We describe two related lines of work that address this. The first deals with national group definitions and, based on evidence from studies carried out in England and analyses of international survey data, argues that the relationship between national identification and prejudice toward immigrants is contingent on the extent to which ethnic or civic definitions of nationality are endorsed. The second, which uses European survey data, examines support for ascribed and acquired criteria that can be applied when determining who is permitted to migrate to one's country, and the various forms of national and individual threat that affect support for these criteria. We explain how the research benefits from a multilevel approach and also suggest how these findings relate to some current policy debates.
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In this study, a genotypification of Leishmaniawas performed using polimerase chain reaction-restriction fragment length polymorfism (PCR-RFLP) and sequencing techniques to identify species of Leishmaniaparasites in phlebotomine sand flies and dogs naturally infected. Between January-February of 2009, CDC light traps were used to collect insect samples from 13 capture sites in the municipality of Posadas, which is located in the province of Misiones of Argentina. Sand flies identified as Lutzomyia longipalpiswere grouped into 28 separate pools for molecular biological analysis. Canine samples were taken from lymph node aspirates of two symptomatic stray animals that had been positively diagnosed with canine visceral leishmaniasis. One vector pool of 10 sand flies (1 out of the 28 pools tested) and both of the canine samples tested positively for Leishmania infantumby PCR and RFLP analysis. PCR products were confirmed by sequencing and showed a maximum identity with L. infantum. Given that infection was detected in one out of the 28 pools and that at least one infected insect was infected, it was possible to infer an infection rate at least of 0.47% for Lu. longipalpisamong the analyzed samples. These results contribute to incriminate Lu. longipalpis as the vector of L. infantumin the municipality of Posadas, where cases of the disease in humans and dogs have been reported since 2005.
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A forensic intelligence process was conducted over cross-border seizures of false identity documents whose sources were partly known to be the same. Visual features of 300 counterfeit Portuguese and French identity cards seized in France and Switzerland were observed and integrated in a structured database developed to detect and analyze forensic links. Based on a few batches of documents known to come from common sources, the forensic profiling method could be validated and its performance evaluated. The method also proved efficient and complementary to conventional means of detecting connections between cases. Cross-border links were detected, highlighting the need for more collaboration. Forensic intelligence could be produced, uncovering the structure of counterfeits' illegal trade, the concentration of their sources and the evolution of their quality over time. In addition, two case examples illustrated how forensic profiling may support specific investigations. The forensic intelligence process and its results will underline the need to develop such approaches to support the fight against fraudulent documents and organized crime.
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This paper lays down some theoretical framework for further research to be made on the subject of how identity of young Slovenian and Catalan users is forming within the social networking website Facebook. The author pursues his interest based on observation of how communicationand thus interaction between users is changing and how this is reflected in everyday practices. In so doing he tries to identify the connections between the individual, society and technology, asthese are more and more interwoven, and we cannot think one without the other in thecontemporary globalised world.
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On the identity of Melipona torrida Friese (Hymenoptera, Apidae). Melipona marginata var. torrida Friese, 1916, described from three workers putatively collected in Costa Rica, never had its identity properly recognized. Since its original description, no additional specimens have ever been collected in Costa Rica. It is argued here that Melipona torrida was based on mislabeled specimens and corresponds to Melipona marginata obscurior Moure, 1971, a form known only from southern Brazil, Argentina and Paraguay. A lectotype is designated for Melipona torrida and notes on the type material of Melipona marginata obscurior are provided. Other known examples of species described from mislabeled specimens in Friese's Zur Bienenfauna von Costa Rica are discussed. It is pointed out that additional names proposed in this work, based on material from Costa Rica, might turn out to correspond to South American taxa. Also, the date of publication of this Friese's paper is discussed.
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The taxonomic identity of the butterfly Heliconius melpomene f. pyritosa var. fumigata Zikán, 1937 (Nymphalidae: Heliconiinae) is discussed based on the discovery of the specimen based on which this name was assigned. The specimen is not a variation of Eueides tales surdus Stichel, 1903, as previously stated, but is in fact a variation of H. melpomene f. pyritosa, which is a synonym of Heliconius erato amalfreda Riffarth, 1901.
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The HbpR protein is the sigma54-dependent transcription activator for 2-hydroxybiphenyl degradation in Pseudomonas azelaica. The ability of HbpR and XylR, which share 35% amino acid sequence identity, to cross-activate the PhbpC and Pu promoters was investigated by determining HbpR- or XylR-mediated luciferase expression and by DNA binding assays. XylR measurably activated the PhbpC promoter in the presence of the effector m-xylene, both in Escherichia coli and Pseudomonas putida. HbpR weakly stimulated the Pu promoter in E. coli but not in P. azelaica. Poor HbpR-dependent activation from Pu was caused by a weak binding to the operator region. To create promoters efficiently activated by both regulators, the HbpR binding sites on PhbpC were gradually changed into the XylR binding sites of Pu by site-directed mutagenesis. Inducible luciferase expression from mutated promoters was tested in E. coli on a two plasmid system, and from mono copy gene fusions in P. azelaica and P. putida. Some mutants were efficiently activated by both HbpR and XylR, showing that promoters can be created which are permissive for both regulators. Others achieved a higher XylR-dependent transcription than from Pu itself. Mutants were also obtained which displayed a tenfold lower uninduced expression level by HbpR than the wild-type PhbpC, while keeping the same maximal induction level. On the basis of these results, a dual-responsive bioreporter strain of P. azelaica was created, containing both XylR and HbpR, and activating luciferase expression from the same single promoter independently with m-xylene and 2-hydroxybiphenyl.