Misalignment of the microquasar V4641 Sgr (SAX J1819.3--2525)

In the microquasar V4641 Sgr the spin of the black hole is thought to be misaligned with the binary orbital axis. The accretion disc aligns with the black hole spin by the Lense-Thirring effect near to the black hole and further out becomes aligned with the binary orbital axis. The inclination of the radio jets and the Fe$K\alpha$ line profile have both been used to determine the inclination of the inner accretion disc but the measurements are inconsistent. Using a steady state analytical warped disc model for V4641 Sgr we find that the inner disc region is flat and aligned with the black hole up to about $900 R_{\rm g}$. Thus if both the radio jet and fluorescent emission originates in the same inner region then the measurements of the inner disc inclination should be the same.Comment: Accepted for publication in MNRA

Noise reduction for DIC measurements

Digital image correlation (DIC) is well known as a contact‐less, full‐field strain and displacement measuring method. The use of the method is widely spread in experimental mechanics. Nevertheless, there are error sources such as light settings, speckle pattern and noisy images, which strongly affect measurement quality, but often stays uninvestigated. Therefore, this work outlines a simple routine to identify errors and enhance the accuracy of DIC measurements. A calibration sample adapted to the specifications of the setup using the beam theory to link machine displacement, DIC measurements and forces. All evaluations are done in the commercial software ISTRA4D. The noise in the measurements is reduced to an error of under two per cent. The routine allows estimating the quality of the images before performing the experiments. Furthermore, the routine is transferable to all experimental setups. The calibration of the setup allows getting reliable experimental results with a known error. With this estimated stochastic error, the advantages of DIC can be used to evaluate mechanical experiments such as three‐point bending tests on single struts of an open cell metal foam

Micromechanical Characterisation of Ni/PU Hybrid Foams

The computer-aided design of individual parts and the desire for weight reduction and material savings require further development of new hybrid materials. Ni/PU hybrid foams as a new hybrid material offer great potential for the production of components that are lightweight and yet can absorb large amounts of energy. The development of this structured material is at its beginning and mechanical characterisation on all scales is necessary. Experimental investigations on individual struts must be carried out on the micro scale to understand the structure-properties-relationship. Inspite of the challenges raising due to the complex geometry of the struts, tensile tests, three-point bending tests and micro sections are presented in this work. Due to the stiff Ni coating on the outer diameter of the struts, the resistance against bending is around five times as high as against tensile loading. The correlation between the behaviour of the struts and the macroscopic material behaviour validates the planned use of the foams as energy absorbers

Virtuelles Labor für Ni/PU-Hybridschäume - der Weg von experimentellen Untersuchungen zur virtuellen Auslegung

Steigende Anforderungen an Gewicht, Stabilität und Kosten von Bauteilen erfordern den Einsatz von immer leichteren, steiferen und günstigeren Strukturen. Durch die Beschichtung eines kostengünstigen Polyurethan-Schaums mit nanokristallinem Nickel, bieten Ni/PU-Hybridschäume eine gute Lösung. Die Charakterisierung des Materials ist allerdings eine Herausforderung. Die komplexe Struktur-Eigenschafts-Beziehung des Schaums erfordert eine hohe Anzahl an Versuchen, um ein umfassendes Materialverständnis zu erhalten. Zusätzlich dauern Finite-Elemente-Simulationen durch ihre Komplexität sehr lange, wodurch bislang der breite industrielle Einsatz des Hybridschaums verhindert wird. Diese Arbeit präsentiert ein Virtuelles Labor für Hybridschäume. Dazu wird zunächst eine experimentelle Charakterisierung des Schaums vorgenommen, wobei zunächst die Erhöhung der Messgenauigkeit der digitalen Bildkorrelation im Fokus steht. Die hohe Messgenauigkeit ermöglicht die präzise Untersuchung von individuellen Stegen unter Zug- und Biegebelastung. Die mikromechanisch ermittelten Materialparameter dienen als Input für ein Simulationsmodell auf Basis einfacher Einheitszellen. Dabei zeigt die Verifikation auf der Porenebene gute Übereinstimmungen der Ergebnisse. Der abschließende Vergleich der experimentellen und simulativen Untersuchungen der Makroebene bestätigt die Ergebnisse. Durch das Virtuelle Labor kann ein Schaum exakt entsprechend der vorhandenen Anforderungen ausgelegt werden.Increasing demands on weight, stability and cost of components require the use of ever lighter, stiffer and cheaper structures. By coating a low-cost polyurethane foam with nanocrystalline nickel, Ni/PU hybrid foams offer a good solution. However, characterising the material is a challenge. The complex structure-property-relationship of the foam requires a high number of experiments to obtain a comprehensive understanding of the material. In addition, finite-element-simulations take a long time due to their complexity. This has so far prevented the widespread industrial use of hybrid foam. This work presents the construction of a Virtual Lab for hybrid foams. For this purpose, an experimental characterisation of the foam is first carried out, whereby the focus is initially on increasing the measurement accuracy of the digital image correlation. The high measurement accuracy enables the precise investigation of individual struts under tensile and bending loads. The micromechanically determined material parameters serve as input for a simulation model based on simple unit cells. The verification on the cell scale shows good agreement of the results. The final comparison of the experimental and simulative investigations of the macro scale confirm the results. The Virtual Lab allows a foam to be designed exactly according to the existing requirements

Eighty-six EU policy options for reducing imported deforestation

Despite the importance of tropical forest conservation in achieving global sustainability goals and the key role of forest-risk commodity trade in driving deforestation, consumer country policy options for reducing imported deforestation have received limited scholarly attention. Drawing on gray literature and a European Commission public consultation, we identify 86 policy options for the European Union to address deforestation. We assess the political feasibility and map the “theory of change” (TOC)—the causal chain through which the policies address deforestation—for each of these policy options, identifying a trade-off between feasibility and potential impacts: information-based and cooperative policies, which dominate our sample, typically exhibit high feasibility, but mostly lack convincing TOCs, while more stringent regulatory and market-based policy options generally have lower feasibility. We propose three principles for overcoming the feasibility-impact dilemma: (1) build policies on proven TOCs, (2) use policy mixes, and (3) work with key stakeholders, supply chains, and regions. Images of distressed orangutans in Indonesia and forest fires in Brazil have increased public awareness of deforestation across the globe. Still, deforestation continues more or less unabated, driven by demand for forest-risk commodities, such as palm, soy, cocoa, and beef. What can the European Union (EU) and other consumer regions do to address this problem? Here we present 86 policy options for the EU to address tropical deforestation, identified through a review of gray literature and EU stakeholder consultation responses. Analyzing these, we show that policy options that are politically feasible policies tend to have a weaker theory of change—the causal chain through which the policies address deforestation—setting up a trade-off between feasibility and impact. However, there are exceptions, such as mandatory due diligence, which show potential impact and appear politically feasible. Through policy mixing and working with key stakeholders, supply chains, and producer regions, these barriers can be overcome. Images of distressed orangutans in Indonesia and forest fires in Brazil have increased public awareness of deforestation. Still, deforestation continues unabated, driven by demand for forest-risk commodities, such as palm and soy. Here, we present 86 policy options for the EU to reduce imported deforestation. We identify a trade-off between policy feasibility and potential impact. Mixing different policies and working with key stakeholders, supply chains, and producer regions can help overcome this trade-off

Report on the Implementation of Work Package 4 “Selection and Testing New ICT Tools” in the Framework of the IRNet Project

This article, prepared by an international team of authors – researchers from different scientific areas, connected with ICT, e-learning, pedagogy, and other related disciplines – focuses on the objectives and some results of the IRNet international project. In particular, this article describes the research tools, methods, and some procedures of the Work Package 4 (WP4) “Selection and Testing New ICT tools”: Objectives, Tasks, Deliverables, and implementation of research trips. Researchers from partner universities have analysed the results of WP4 in the context of the next stages and Work Packages of the IRNet project – International Research Network

Restaurant Reviewer Liability For Defamation In A Global Context

A restaurant review may contain statements that the restaurant owners would consider defamatory. While technically there is no bar to a successful defamation suit, there are numerous obstacles, including the opinion nature of the review, the “fair comment” qualified privilege, and free-speech jurisprudence that requires actual malice before a plaintiff can prevail in a defamation suit against a public figure. In jurisdictions outside of the United States, there are similar restrictions that will also create obstacles to the success of the lawsuit. Although the success of the suit would be more likely under other nations’ laws, the obstacles still do not rise to the level of a prohibition on such lawsuits. Any business on either side of the dispute – the writer/publisher of the review vs. the restaurant and its owners – needs to be aware of the evolving law and where a defamation case may or may not be successful. This article examines and discusses obstacles to successful defamation cases in order to provide guidance for businesses that are or may be involved in such litigation

Does carbon pricing reduce air travel? Evidence from the Australian 'Clean Energy Future' policy, July 2012 to June 2014

Aviation emissions are an important contributor to global climatic change. As growth in travel demand continues to outstrip improvements in the fuel efficiency of air travel, the aviation contribution to climate change is likely to grow substantially. Consequently, measures that effectively reduce travel demand are required if atmospheric carbon concentrations are to be limited. The efficacy of the Australian Clean Energy Future policy which placed a $23.00AUD (FY 2012) to$24.15 AUD (FY 2013) per tonne levy on carbon-dioxide equivalent emissions from July 2012 to June 2014 is tested. Specifically, time-series regression is used to estimate the effect of this carbon price policy on the level of domestic passenger kilometres flown in Australia, while adjusting for costs of production (i.e. fuel and labour costs), economic activity (i.e. gross domestic product), competitive effects (i.e. airline capacity), and exogenous shocks. There was no evidence that the carbon price reduced the level of domestic aviation in Australia. Carbon pricing measures may have to be levied at a greater rate to affect behavioural change, particularly given the limited potential for future aviation efficiency gains.The authors are grateful to Paul Peeters, NHTV Breda University of Applied Sciences, for his suggestion of several relevant papers

Molecular mechanism of influenza A NS1-mediated TRIM25 recognition and inhibition

RIG-I is a viral RNA sensor that induces the production of type I interferon (IFN) in response to infection with a variety of viruses. Modification of RIG-I with K63-linked poly-ubiquitin chains, synthesised by TRIM25, is crucial for activation of the RIG-I/MAVS signalling pathway. TRIM25 activity is targeted by influenza A virus non-structural protein 1 (NS1) to suppress IFN production and prevent an efficient host immune response. Here we present structures of the human TRIM25 coiled-coil-PRYSPRY module and of complexes between the TRIM25 coiled-coil domain and NS1. These structures show that binding of NS1 interferes with the correct positioning of the PRYSPRY domain of TRIM25 required for substrate ubiquitination and provide a mechanistic explanation for how NS1 suppresses RIG-I ubiquitination and hence downstream signalling. In contrast, the formation of unanchored K63-linked poly-ubiquitin chains is unchanged by NS1 binding, indicating that RING dimerisation of TRIM25 is not affected by NS1