magma mixing history and dynamics of an eruption trigger

The most violent and catastrophic volcanic eruptions on Earth have been triggered by the refilling of a felsic volcanic magma chamber by a hotter more mafic magma. Examples include Vesuvius 79 AD, Krakatau 1883, Pinatubo 1991, and Eyjafjallajokull 2010. Since the first hypothesis, plenty of evidence of magma mixing processes, in all tectonic environments, has accumulated in the literature allowing this natural process to be defined as fundamental petrological processes playing a role in triggering volcanic eruptions, and in the generation of the compositional variability of igneous rocks. Combined with petrographic, mineral chemistry and geochemical investigations, isotopic analyses on volcanic rocks have revealed compositional variations at different length scales pointing to a complex interplay of fractional crystallization, mixing/mingling and crustal contamination during the evolution of several magmatic feeding systems. But to fully understand the dynamics of mixing and mingling processes, that are impossible to observe directly, at a realistically large scale, it is necessary to resort to numerical simulations of the complex interaction dynamics between chemically different magmas

Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009

Aims. We present an extensive study of the BL Lac object Mrk 501 based on a data set collected during the multi-instrument campaign spanning from 2009 March 15 to 2009 August 1, which includes, among other instruments, MAGIC, VERITAS, Whipple 10 m, and Fermi-LAT to cover the gamma-ray range from 0.1 GeV to 20 TeV; RXTE and Swift to cover wavelengths from UV to hard X-rays; and GASP-WEBT, which provides coverage of radio and optical wavelengths. Optical polarization measurements were provided for a fraction of the campaign by the Steward and St. Petersburg observatories. We evaluate the variability of the source and interband correlations, the gamma-ray flaring activity occurring in May 2009, and interpret the results within two synchrotron self-Compton (SSC) scenarios.Methods. The multiband variability observed during the full campaign is addressed in terms of the fractional variability, and the possible correlations are studied by calculating the discrete correlation function for each pair of energy bands where the significance was evaluated with dedicated Monte Carlo simulations. The space of SSC model parameters is probed following a dedicated grid-scan strategy, allowing for a wide range of models to be tested and offering a study of the degeneracy of model-to-data agreement in the individual model parameters, hence providing a less biased interpretation than the "single-curve SSC model adjustment" typically reported in the literature.Results. We find an increase in the fractional variability with energy, while no significant interband correlations of flux changes are found on the basis of the acquired data set. The SSC model grid-scan shows that the flaring activity around May 22 cannot be modeled adequately with a one-zone SSC scenario (using an electron energy distribution with two breaks), while it can be suitably described within a two (independent) zone SSC scenario. Here, one zone is responsible for the quiescent emission from the averaged 4.5-month observing period, while the other one, which is spatially separated from the first, dominates the flaring emission occurring at X-rays and very-high-energy (> 100 GeV, VHE) gamma-rays. The flaring activity from May 1, which coincides with a rotation of the electric vector polarization angle (EVPA), cannot be satisfactorily reproduced by either a one-zone or a two-independent-zone SSC model, yet this is partially affected by the lack of strictly simultaneous observations and the presence of large flux changes on sub-hour timescales (detected at VHE gamma rays).Conclusions. The higher variability in the VHE emission and lack of correlation with the X-ray emission indicate that, at least during the 4.5-month observing campaign in 2009, the highest energy (and most variable) electrons that are responsible for the VHE gamma rays do not make a dominant contribution to the similar to 1 keV emission. Alternatively, there could be a very variable component contributing to the VHE gamma-ray emission in addition to that coming from the SSC scenario. The studies with our dedicated SSC grid-scan show that there is some degeneracy in both the one-zone and the two-zone SSC scenarios probed, with several combinations of model parameters yielding a similar model-to-data agreement, and some parameters better constrained than others. The observed gamma-ray flaring activity, with the EVPA rotation coincident with the first gamma-ray flare, resembles those reported previously for low frequency peaked blazars, hence suggesting that there are many similarities in the flaring mechanisms of blazars with different jet properties

School inspectors, policy implementers, policy shapers: influences and activities

This chapter introduces the idea of school inspectors as implementers of public policy, framing their role within the context of policy implementation and the governance of education. Using a framework for policy implementation developed by Weible and Sabatier (2006), it presents a modified framework for inves-tigating inspectors’ work and practices as policy implementers. In so doing it questions their role as policy shapers and policy coalition workers in the context of the practice of inspection in Finland, Sweden, England, Germany, The German State of Lower Saxony, The Netherlands, The Republic of Ireland and The Austrian province of Styria. In introducing the idea of policy learning it introduces the ways in which policy learning theory has contributed to implementation theory, in order to further reflect on these issues in the final chapter of this book

Recent technological developments in MALDI-MSI based hair analysis

Hair is a common piece of trace evidence found at a crime scene, however, often it is not possible to obtain DNA (due to the lack of a follicular root). These hair samples could potentially provide other intelligence, based on the molecular history of an individual that it contains. Currently, this type of analysis is performed using traditional hyphenated techniques gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-mass spectrometry (LC-MS). However, these techniques require a large amount of hair, not a few single strands such as those typically found at a crime scene and also involve extensive sample preparation. Recently new technologies such as matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) have been used to monitor the distribution of drugs of abuse in single hair strands. Using this technology it is possible to reveal the distribution of compounds in the hair more accurately and in single strands as opposed to milligram quantities required by traditional hyphenated methods. The use of MALDI-MSI could provide law enforcement agencies with lifestyle information on an individual and help to narrow down the pool of suspects

Odločitveni model za pomoč pri izbiri telekomunikacijskega sistema

notes: The authors would like to thank Kenneth Fox and Richard Kelly at the House of Commons for their assistance with this research, and to the editors of this volume. This research was supported by the UK Higher Education Authority / Parliamentary Outreach Service and European Research Council’s grant no. 230267 for the project of Analysis of Learning in Regulatory Governance, ALREG (http://centres.exeter.ac.uk/ceg/research/ALREG/index.php).publication-status: SubmittedThis chapter uses the Narrative Policy Framework (NPF) to analyse and compare the parliamentary hearings on the ‘Arab Spring’ of 2011/12 in the UK and the USA. The presence of bias is the main rationale for bringing experts into parliamentary life. However, drawing on the insights of behavioural sciences, our findings show that the politicians’ heuristics were not ‘fixed’ by experts’ testimonies. Rather than generate narrative learning, or at least reduce bias, we have found that there is more evidence for narratives as political devices. Beyond this, the chapter demonstrates the utility for NPF for those who operate in ‘qualitative analysis mode’ and evaluate the work of democratic institutions

Blame, Reputation, and Organizational Responses to a Politicized Climate

Hinterleitner and Sager conceptualize how public sector organizations (PSOs) react to elite polarization, which is as an increasingly common phenomenon in Western democracies. For politicians operating under polarized conditions, PSOs are a primary blame-deflection target. Since blame from politicians presents a threat to the reputation of PSOs, they react to these threats. While research has made progress in examining specific responses to reputational threats, the authors argue that an overarching categorization of responses is missing. The chapter adapts the concept of anticipatory blame avoidance to the decision-making of PSOs, using it as an umbrella concept to categorize and systematize the reactions of PSOs. PSOs that prioritize crafting responses to reputational threats may neglect tasks and duties potentially decisive for effective and problem-oriented public service delivery