Architecture of the fungal nuclear pore inner ring complex

The nuclear pore complex (NPC) constitutes the sole gateway for bidirectional nucleocytoplasmic transport. We present the reconstitution and interdisciplinary analyses of the ~425-kDa inner ring complex (IRC), which forms the central transport channel and diffusion barrier of the NPC, revealing its interaction network and equimolar stoichiometry. The Nsp1•Nup49•Nup57 channel nucleoporin hetero-trimer (CNT) attaches to the IRC solely through the adaptor nucleoporin Nic96. The CNT•Nic96 structure reveals that Nic96 functions as an assembly sensor that recognizes the three dimensional architecture of the CNT, thereby mediating the incorporation of a defined CNT state into the NPC. We propose that the IRC adopts a relatively rigid scaffold that recruits the CNT to primarily form the diffusion barrier of the NPC, rather than enabling channel dilation

Dynamic correlations and volatility linkages between stocks and sukuk: evidence from international markets

An understanding of volatility and co-movements in financial markets is important for portfolio allocation and risk management practices. The current financial crisis caused a shrinkage in values of most assets, an increased volatility and a threat to the survival of several institutional investors. Managing risks and returns within the classic portfolio theory, when correlations across securities soar, is increasingly challenging. In this paper, we investigate the volatility behavior and the co-movements between sukuk and international stock indexes. Symmetric multivariate GARCH models with dynamic conditional correlations (DCC) were estimated under student-t distribution. We provide evidence of high correlations between sukuk and US and EU stock markets, without finding the well-known flight to quality behavior affecting Islamic bonds. We also show that volatility linkages between sukuk and regional market indexes are higher during financial crisis. We argue that investors could obtain diversification benefits including sukuk in a well \u2013diversified equity portfolio, given their lower volatility compared to equity. But higher volatility linkages and dynamic correlations during financial crises show that they are hybrid instruments between bonds and equity. Our findings are relevant for institutional investors and asset managers, that include Islamic bonds in a diversified portfolio

Shades of empire: police photography in German South-West Africa

This article looks at a photographic album produced by the German police in colonial Namibia just before World War I. Late 19th- and early 20th-century police photography has often been interpreted as a form of visual production that epitomized power and regimes of surveillance imposed by the state apparatuses on the poor, the criminal and the Other. On the other hand police and prison institutions became favored sites where photography could be put at the service of the emergent sciences of the human body—physiognomy, anthropometry and anthropology. While the conjuncture of institutionalized colonial state power and the production of scientific knowledge remain important for this Namibian case study, the article explores a slightly different set of questions. Echoing recent scholarship on visuality and materiality the photographic album is treated as an archival object and visual narrative that was at the same time constituted by and constitutive of material and discursive practices within early 20th-century police and prison institutions in the German colony. By shifting attention away from image content and visual codification alone toward the question of visual practice the article traces the ways in which the photo album, with its ambivalent, unstable and uncontained narrative, became historically active and meaningful. Therein the photographs were less informed by an abstract theory of anthropological and racial classification but rather entrenched with historically contingent processes of colonial state constitution, socioeconomic and racial stratification, and the institutional integration of photography as a medium and a technology into colonial policing. The photo album provides a textured sense of how fragmented and contested these processes remained throughout the German colonial period, but also how photography could offer a means of transcending the limits and frailties brought by the realities on the ground.International Bibliography of Social Science

A strengthened formulation and cutting planes for the open pit mine production scheduling problem

We present an integer programming formulation for the open pit mine production scheduling problem. We strengthen this formulation by adding inequalities derived by combining the precedence and production constraints. The addition of these inequalities decreases the computational requirements to obtain the optimal integer solution, in many cases by a significant margin

Precedence constrained knapsack problem data instances

Data instances for the journal article "Clique-based facets for the precedence constrained knapsack problem" by the same authors

Clique-based facets for the precedence constrained knapsack problem

We consider a knapsack problem with precedence constraints imposed on pairs of items, known as the precedence constrained knapsack problem (PCKP). This problem has applications in manufacturing and mining, and also appears as a subproblem in decomposition techniques for network design and related problems. We present a new approach for determining facets of the PCKP polyhedron based on clique inequalities. A comparison with existing techniques, that lift knapsack cover inequalities for the PCKP, is also presented. It is shown that the clique-based approach generates facets that cannot be found through the existing cover-based approaches, and that the addition of clique-based inequalities for the PCKP can be computationally beneficial, for both PCKP instances arising in real applications, and applications in which PCKP appears as an embedded structure