Cretaceous-Tertiary geodynamics: a North Atlantic exercise

New reconstructions are presented for the Cretaceous–Early Tertiary North Atlantic using a combination of palaeomagnetic, hotspot and magnetic anomaly data. We utilize these reconstructions in an analysis of previously described misfits between the North Atlantic Plate elements at successive intervals during this time period. We are able to achieve reasonable overlap between the hotspot and palaeomagnetic reconstructions between 40 and 95 Ma and thus are able to support the idea that the Indo–Atlantic hotspots are relatively stationary. Small, but systematic discrepancies for this time interval can readily be modelled with a long-term, octopole non-dipole field contribution (G3 = g₃⁰/g₁⁰ = 0.08). However, hotspot and palaeomagnetic reconstructions for the Early Cretaceous North Atlantic show substantial differences that cannot be explained by constant, non-dipole fields and we favour an explanation for these discrepancies in terms of true polar wander (TPW) triggered by mantle instabilities between 125 and 95 Ma; this constitutes the only identifiable event of significant TPW since the Early Cretaceous. Taken in the context of available geochronological and geological data and seismic tomography from the region, the 95–40 Ma reconstructions and their time-consequent geological products are interpreted in terms of specific conditions of mantle-crust coupling and global plate motions/tectonic activity. Highlights from these reconstructions show uniform NE movement of the coupled North American, Greenland and Eurasian plates from 95 to 80 Ma; a marked cusp in the paths for all three elements at 80 Ma where the three plates simultaneously change direction and follow a uniform NW-directed motion until c. 20 Ma when Eurasia diverges NE, away from the still-NW-moving Greenland and North American elements. Positioning of the Iceland plume beneath the spreading-ridge at 20 Ma may have increased upwelling below the ridge, increased the ridge-push, and caused a NE shift in the absolute direction of Eurasia

Relinquishing and Governing the Volatile: The Many Afghanistans and Critical Research Agendas of NATO's Governance

This article invites academics and policy analysts to examine the mechanisms and legacy of NATO's security and development governance of Afghan social spaces by using critical theory concepts. It argues that such scholarly endeavors are growing in importance as the United States and NATO gradually pull their troops out of Afghanistan. Thus, the article suggests a broad twofold research agenda. First, it points out that researching social spaces such as towns, villages, marketplaces, and neighborhoods beyond the realm of intergovernmental politics can lead to thick descriptions of how such places have been governed from within by agents external to them. Second, the study argues for a multifaceted examination of instruments, strategies, and institutions of security governance, its conduct and social effects by deploying critical and Foucauldian concepts such as the rationality and apparatuses of power relations. Thereby, it proposes an inquiry into Provincial Reconstruction Teams and Afghan National Security Forces as spatially and temporally specific apparatuses of surveillance and security

Scandinavian perspectives on plant gene technology: applications, policies and progress

Plant research and breeding has a long and successful history in the Scandinavian countries, Denmark, Finland, Norway and Sweden. Researchers in the region have been early in adopting plant gene technologies as they developed. This review gives a background, as well as discuss the current and future progress of plant gene technology in these four countries. Country-specific details of the regulation of genetically modified plants are described, as well as similarities and differences in the approach to regulation of novel genome-editing techniques. Also, the development of a sustainable bioeconomy may encompass the application of plant gene technology and we discuss whether or not this is reflected in current associated national strategies. In addition, country-specific information about the opinion of the public and other stakeholders on plant gene technology is presented, together with a country-wise political comparison and a discussion of the potential reciprocal influence between public opinion and the political process of policy development. The Scandinavian region is unique in several aspects, such as climate and certain agriculturally related regulations, and at the same time the region is vulnerable to changes in plant breeding investments due to the relatively small market sizes. It is therefore important to discuss the role and regulation of innovative solutions in Scandinavian plant research and breeding.Peer reviewe

Toward a simulation approach for alkene ring-closing metathesis : scope and limitations of a model for RCM

A published model for revealing solvent effects on the ring-closing metathesis (RCM) reaction of di-Et diallylmalonate 7 has been evaluated over a wider range of conditions, to assess its suitability for new applications. Unfortunately, the model is too flexible and the published rate consts. do not agree with exptl. studies in the literature. However, by fixing the values of important rate consts. and restricting the concn. ranges studied, useful conclusions can be drawn about the relative rates of RCM of different substrates, precatalyst concn. can be simulated accurately and the effect of precatalyst loading can be anticipated. Progress has also been made toward applying the model to precatalyst evaluation, but further modifications to the model are necessary to achieve much broader aims

Linac-LHC EP Collider Options

We describe various parameter scenarios for a ring-linac ep collider based on LHC and an independent electron linac. Luminosities between $10^{31}$ and $10^{33} cm^{-2}s^{-1}$ can be achieved with a s.c. linac, operated either in pulsed or in cw mode, with optional recirculation, at a total electric wallplug power of order 20 MW. Higher luminosities, of several $10^{33} cm^{-2}s^{-1}$ can be reached by investing more electric power or by energy recovery. Finally, merits of a linac-ring ep collider are discussed

Guest Lecture – Foundation Engineering for Gravity Structures in the Northern North Sea

During the past 10 years, 15 gravity structures have been installed in the northern North Sea. As new gravity structures are being designed for installation on softer soils and at greater depths, they still pose a great challenge to soil mechanics and foundation engineering. Great improvements have been made during the 10-year period. This applies to soil investigations, in-situ measurements, undisturbed sampling, laboratory testing and design analyses. Compared to structures on land, offshore gravity structures are characterised by large foundation areas, the installation method, and the cyclic wave loading state. The paper reviews investigation methods, site and soil conditions, construction principles, instrumentation and installation. The main emphasis, however, is given to current foundation design practice and experiences from full scale measurements

The Large Hadron-Electron Collider (LHEC) at the LHC

Sub-atomic physics at the energy frontier probes the structure of the fundamental quanta of the Universe. The Large Hadron Collider (LHC) at CERN opens for the first time the ‘terascale’ (TeV energy scale) to experimental scrutiny, exposing the physics of the Universe at the subattometric (∼ 10−19 m, 10−10 as) scale. The LHC will also take the science of nuclear matter to hitherto unparalleled energy densities. The hadron beams, protons or ions, in the LHC underpin this horizon, and also offer new experimental possibilities at this energy scale. A Large Hadron electron Collider, LHeC, in which an electron (positron) beam of energy 60 to 140 GeV is in collision with one of the LHC hadron beams, makes possible terascale leptonhadron physics. The LHeC is presently being evaluated in the form of two options, ‘ring-ring’ and ‘linac-ring’, either of which operate simultaneously with pp or ion-ion collisions in other LHC interaction regions. Each option takes advantage of recent advances in radio-frequency, in linear acceleration, and in other associated technologies, to achieve ep luminosity as large as 1033 cm−2s−1

Gaps in access and school attainments among people with and without disabilities: a case from Nepal

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A Large Hadron Electron Collider at CERN

This document provides a brief overview of the recently published report on the design of the Large Hadron Electron Collider (LHeC), which comprises its physics programme, accelerator physics, technology and main detector concepts. The LHeC exploits and develops challenging, though principally existing, accelerator and detector technologies. This summary is complemented by brief illustrations of some of the highlights of the physics programme, which relies on a vastly extended kinematic range, luminosity and unprecedented precision in deep inelastic scattering. Illustrations are provided regarding high precision QCD, new physics (Higgs, SUSY) and electron-ion physics. The LHeC is designed to run synchronously with the LHC in the twenties and to achieve an integrated luminosity of O(100) fb$^{-1}$. It will become the cleanest high resolution microscope of mankind and will substantially extend as well as complement the investigation of the physics of the TeV energy scale, which has been enabled by the LHC