CAIR: Using Formal Languages to Study Routing, Leaking, and Interception in BGP

The Internet routing protocol BGP expresses topological reachability and policy-based decisions simultaneously in path vectors. A complete view on the Internet backbone routing is given by the collection of all valid routes, which is infeasible to obtain due to information hiding of BGP, the lack of omnipresent collection points, and data complexity. Commonly, graph-based data models are used to represent the Internet topology from a given set of BGP routing tables but fall short of explaining policy contexts. As a consequence, routing anomalies such as route leaks and interception attacks cannot be explained with graphs. In this paper, we use formal languages to represent the global routing system in a rigorous model. Our CAIR framework translates BGP announcements into a finite route language that allows for the incremental construction of minimal route automata. CAIR preserves route diversity, is highly efficient, and well-suited to monitor BGP path changes in real-time. We formally derive implementable search patterns for route leaks and interception attacks. In contrast to the state-of-the-art, we can detect these incidents. In practical experiments, we analyze public BGP data over the last seven years

Shear-band arrest and stress overshoots during inhomogeneous flow in a metallic glass

At the transition from a static to a dynamic deformation regime of a shear band in bulk metallic glasses, stress transients in terms of overshoots are observed. We interpret this phenomenon with a repeated shear-melting transition and are able to access a characteristic time for a liquidlike to solidlike transition in the shear band as a function of temperature, enabling us to understand why shear bands arrest during inhomogenous serrated flow in bulk metallic glasses

Multiphase imaging of freezing particle suspensions by confocal microscopy

Ice-templating is a well-established processing route for porous ceramics. Because of the structure/properties relationships, it is essential to better understand and control the solidification microstructures. Ice-templating is based on the segregation and concentration of particles by growing ice crystals. What we understand so far of the process is based on either observations by optical or X-ray imaging techniques, or on the characterization of ice-templated materials. However, in situ observations at particle-scale are still missing. Here we show that confocal microscopy can provide multiphase imaging of ice growth and the segregation and organization of particles. We illustrate the benefits of our approach with the observation of particles and pore ice in the frozen structure, the dynamic evolution of the freeze front morphology, and the impact of PVA addition on the solidification microstructures. These results prove in particular the importance of controlling both the temperature gradient and the growth rate during ice-templating.Comment: 20 pages, 9 figure

SCUBA Observations of the Host Galaxies of Gamma-Ray Bursts

In recent years, a population of galaxies with huge infrared luminosities and dust masses has been discovered in the submillimetre. Observations suggest that the AGN contribution to the luminosities of these submillimetre-selected galaxies is low; instead their luminosities are thought to be mainly due to strong episodes of star formation following merger events. Our current understanding of GRBs as the endpoints in the life of massive stars suggest that they will be located in such galaxies.We have observed a sample of well-located GRB host galaxies in the submillimetre. Comparing the results with the general submillimetre-selected galaxy population, we find that at low fluxes (S850 ≤ 4 mJy), the two agree well. However, there is a lack of bright GRB hosts in the submillimetre. This finding is reinforced when the results of other groups are included. Possible explanations are discussed. These results help us assess the roles of both GRB host galaxies and submillimetre-selected galaxies in the evolution of the Universe

Mutual effects of land distribution and economic development : evidence from Asia, Africa, and Latin America

Land plays an important role in the economies of developing countries, and many theories connecting land inequality with different dimensions of economic development already exist. Even though efficacious land distribution allows societies to transition from poverty to a human capital-based developed economy, ongoing issues related to property rights, inequality, and the political economy of land distribution are unavoidable. The general objective of this paper is to explore the nexus between land distribution and economic development. The specific objectives are to: (i) identify which land distribution programs/activities contribute to economic development; (ii) investigate the role of stakeholders in land distribution programs that affect the growth of productivity; and (iii) assess the deficiencies of current land distribution policies in Asia, Africa, and Latin America to explore how economic development theories contribute to decreasing income inequality. This paper provides an overview of land distribution history and the main economic development theories. It also highlights the links between land distribution and the main elements of economic development. Finally, it provides a comparative review of the most recent empirical works regarding the characteristics, limitations, and potential (mutual) effects of land distribution and economic development settings on developing countries worldwide

Austerity, globalisation and alternatives

This article argues that austerity is not necessary or externally determined. It is an active class project and an ideological choice of elites and the powerful. There are alternatives to austerity. One is based around equality and economic and social rights. Others involve the restructuring of work to a society based on less paid work, and freedom of movement in a global society of open borders. These would help counter austerity and have benefits of their own

Deconvolution of complex G protein-coupled receptor signaling in live cells using dynamic mass redistribution measurements

Label-free biosensor technology based on dynamic mass redistribution (DMR) of cellular constituents promises to translate GPCR signaling into complex optical 'fingerprints' in real time in living cells. Here we present a strategy to map cellular mechanisms that define label-free responses, and we compare DMR technology with traditional second-messenger assays that are currently the state of the art in GPCR drug discovery. The holistic nature of DMR measurements enabled us to (i) probe GPCR functionality along all four G-protein signaling pathways, something presently beyond reach of most other assay platforms; (ii) dissect complex GPCR signaling patterns even in primary human cells with unprecedented accuracy; (iii) define heterotrimeric G proteins as triggers for the complex optical fingerprints; and (iv) disclose previously undetected features of GPCR behavior. Our results suggest that DMR technology will have a substantial impact on systems biology and systems pharmacology as well as for the discovery of drugs with novel mechanisms

Expressive political behaviour : foundations, scope and implications

A growing literature has focused attention on ‘expressive’ rather than ‘instrumental’ behaviour in political settings, particularly voting. A common criticism of the expressive idea is that it is ad hoc and lacks both predictive and normative bite. No clear definition of expressive behaviour has gained wide acceptance yet, and no detailed understanding of the range of foundations of specific expressive motivations has emerged. This article provides a foundational discussion and definition of expressive behaviour accounting for a range of factors. The content of expressive choice – distinguishing between identity-based, moral and social cases – is discussed and related to the specific theories of expressive choice in the literature. There is also a discussion of the normative and institutional implications of expressive behaviour