Cement distribution, volume, and compliance in vertebroplasty: some answers from an anatomy-based nonlinear finite element study

STUDY DESIGN: The biomechanics of vertebral bodies augmented with real distributions of cement were investigated using nonlinear finite element (FE) analysis. OBJECTIVES: To compare stiffness, strength, and stress transfer of augmented versus nonaugmented osteoporotic vertebral bodies under compressive loading. Specifically, to examine how cement distribution, volume, and compliance affect these biomechanical variables. SUMMARY OF BACKGROUND DATA: Previous FE studies suggested that vertebroplasty might alter vertebral stress transfer, leading to adjacent vertebral failure. However, no FE study so far accounted for real cement distributions and bone damage accumulation. METHODS: Twelve vertebral bodies scanned with high-resolution pQCT and tested in compression were augmented with various volumes of cements and scanned again. Nonaugmented and augmented pQCT datasets were converted to FE models, with bone properties modeled with an elastic, plastic and damage constitutive law that was previously calibrated for the nonaugmented models. The cement-bone composite was modeled with a rule of mixture. The nonaugmented and augmented FE models were subjected to compression and their stiffness, strength, and stress map calculated for different cement compliances. RESULTS: Cement distribution dominated the stiffening and strengthening effects of augmentation. Models with cement connecting either the superior or inferior endplate (S/I fillings) were only up to 2 times stiffer than the nonaugmented models with minimal strengthening, whereas those with cement connecting both endplates (S + I fillings) were 1 to 8 times stiffer and 1 to 12 times stronger. Stress increases above and below the cement, which was higher for the S + I cases and was significantly reduced by increasing cement compliance. CONCLUSION: The developed FE approach, which accounts for real cement distributions and bone damage accumulation, provides a refined insight into the mechanics of augmented vertebral bodies. In particular, augmentation with compliant cement bridging both endplates would reduce stress transfer while providing sufficient strengthening.

Vom gesellschaftlichen Engagement für den Islam zum islamischen Engagement für die Gesellschaft – Verschiebungen In Tariq Ramadans Plädoyer für eine ganzheitliche Moderne

Tariq Ramadan (born 1962) is not only a leading thinker of Islamic Reformism, but also the most prominent Muslim actor in the ongoing reconfiguration of secularity in Europe. As a guiding back- ground, the introduction to this paper establishes that by now a public role for religion in secular societies is widely accepted, albeit attached to conditions (1). After an insight into the self-posi- tioning of Ramadan, followed by a comprehensive overview of secondary literature (2), I argue for two – discernible rather than clear-cut – phases to be identified within his discourse over 16 years: Considering secular societies as devoid of values, Ramadan promotes a distinct Islamic alternative that grounds its (modern) principles (allegedly) in revelation only, and also includes specific norms of Islamic law (3). Later, the Islam to be realized consists almost exclusively of ethics – of which the basic values are shared by, and even to be established with, all members of society (4). Ramadan’s continuous plea for a holistic modernity is elaborated on at the end of this paper (5).

The Trade Versus Culture Discourse: Tracing its Evolution in Global Law

The intensified flows of goods, services, peoples and ideas across borders intrinsic to globalization have had numerous and multi-faceted effects. Those affecting culture have been perhaps the most controversial, as it is more often than not difficult to identify the spill-overs across economic and non-economic areas and across borders, as it is equally hard to qualify the effects of these spill-overs as positive or negative. The debate also tends to be politically and even emotionally charged, which has so far not proven advantageous to establishing a genuine dialogue, nor to finding solutions. This contention and the divergent interests of major players in the international community have been reflected in the institutions and rules of global law. It is the objective of this chapter to explore this institutional architecture, in particular its main (and opposing) constituent fora of the World Trade Organization (WTO) and the United Nations Educational Social and Cultural Organization (UNESCO). The chapter traces the evolution of these institutions and their interaction over time, as well as the underlying objectives, demands and strategies of the key proponents in the trade versus culture discourse, which ultimately shaped the existent law and policy. The chapter concludes with an appraisal of the present state of affairs situating the discussion into the contemporary global governance landscape.

Trypanosomal TAC40 constitutes a novel subclass of mitochondrial -barrel proteins specialized in mitochondrial genome inheritance

Mitochondria cannot form de novo but require mechanisms allowing their inheritance to daughter cells. In contrast to most other eukaryotes Trypanosoma brucei has a single mitochondrion whose single-unit genome is physically connected to the flagellum. Here we identify a β-barrel mitochondrial outer membrane protein, termed tripartite attachment complex 40 (TAC40), that localizes to this connection. TAC40 is essential for mitochondrial DNA inheritance and belongs to the mitochondrial porin protein family. However, it is not specifically related to any of the three subclasses of mitochondrial porins represented by the metabolite transporter voltage-dependent anion channel (VDAC), the protein translocator of the outer membrane 40 (TOM40), or the fungi-specific MDM10, a component of the endoplasmic reticulum–mitochondria encounter structure (ERMES). MDM10 and TAC40 mediate cellular architecture and participate in transmembrane complexes that are essential for mitochondrial DNA inheritance. In yeast MDM10, in the context of the ERMES, is postulated to connect the mitochondrial genomes to actin filaments, whereas in trypanosomes TAC40 mediates the linkage of the mitochondrial DNA to the basal body of the flagellum. However, TAC40 does not colocalize with trypanosomal orthologs of ERMES components and, unlike MDM10, it regulates neither mitochondrial morphology nor the assembly of the protein translocase. TAC40 therefore defines a novel subclass of mitochondrial porins that is distinct from VDAC, TOM40, and MDM10. However, whereas the architecture of the TAC40-containing complex in trypanosomes and the MDM10-containing ERMES in yeast is very different, both are organized around a β-barrel protein of the mitochondrial porin family that mediates a DNA–cytoskeleton linkage that is essential for mitochondrial DNA inheritance.

Minor inheritance inhibits the calibration of the 10Be production rate from the AD 1717 Val Ferret rock avalanche, European Alps

To calibrate the in situ 10Be production rate, we collected surface samples from nine large granitic boulders within the deposits of a rock avalanche that occurred in AD 1717 in the upper Ferret Valley, Mont Blanc Massif, Italy. The 10Be concentrations were extremely low and successfully measured within 10% analytical uncertainty or less. The concentrations vary from 4829 ± 448 to 5917 ± 476 at g−1. Using the historical age exposure time, we calculated the local and sea level-high latitude (i.e. ≥60°) cosmogenic 10Be spallogenic production rates. Depending on the scaling schemes, these vary between 4.60 ± 0.38 and 5.26 ± 0.43 at g−1 a−1. Although they correlate well with global values, our production rates are clearly higher than those from more recent calibration sites. We conclude that our 10Be production rate is a mean and an upper bound for production rates in the Massif region over the past 300 years. This rate is probably influenced by inheritance and will yield inaccurate (e.g. too young) exposure ages when applied to surface-exposure studies in the area. Other independently dated rock-avalanche deposits in the region that are approximately 103 years old could be considered as possible calibration sites.

Europeanization, Institutional Changes and Differential Empowerment

The issue of European integration is of utmost importance for contemporary Swiss politics, as underscored by the presence of three decision-making processes relating to bilateral agreements with the EU, and two additional processes with a strong European dimension (the telecommunication act and the immigration law), among the 11 most important processes of the early 2000s. Previous chapters have highlighted substantial differences between domestic and Europeanized decision-making processes in terms of institutional design and decision-making structures. Chapters 2 and 3 suggest that the peculiarities of the three decision-making processes relating to bilateral agreements go along with specific power configurations among political actors. Chapter 5 draws our attention to the impact of Europeanization on the specific decision-making structure at work in a given policy process.

Addressing climate change under preferential trade agreements: Towards alignment of carbon standards under the Transatlantic Trade and Investment Partnership

With its wide coverage of economic spheres and the variety of trade and investment measures currently under negotiation, the Transatlantic Trade and Investment Partnership opens windows of opportunity for advancing action on climate change. We examine possible avenues and international trade law implications for an alignment of carbon-related standards between the EU and the US. We compare EU and US carbon emissions standards for cars and argue that negotiators should strive for a mutual recognition of their equivalence for a transitional period, while pursuing the goal of full harmonization at the level of the highest standards of two parties at some date in the future. This could be a way to balance between economic and environmental interests and harness economic incentives for the benefit of climate.

Toward alignment of carbon standards under the Transatlantic Trade and Investment Partnership

With its wide coverage of economic spheres and the variety of trade and investment measures currently under negotiation, the Transatlantic Trade and Investment Partnership (TTIP) opens windows of opportunity for climate change mitigation and adaptation. The paper examines the possible avenues and the WTO law implications for the alignment of emissions standards between the European Union (EU) and United States of America (US). Looking particularly at the automobile sector, it argues that TTIP negotiators should strive for the mutual recognition of equivalence of EU and US car emissions standards, while pursuing full harmonisation in the long term. It concludes that the preferential trade agreement (PTA) status of TTIP would not be able to exempt measures taken for regulatory convergence from compliance with applicable WTO rules, particularly the rules of the WTO’s Agreement on Technical Barriers to Trade (TBT). Furthermore, the EU and the US would not be able to ignore requests for the recognition of equivalence of third countries’ standards and would need to provide the grounds upon which they assess third countries’ standards as not adequately fulfilling the objectives of their own regulations and therefore rejecting them.