Recognising and understanding collective resilience in crowds of survivors

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Talking about Hillsborough: ‘panic’ as discourse in survivors' accounts of the 1989 football stadium disaster

Popular representations of crowd behaviour in disasters are often characterised by irrationalist discourses, in particular ‘mass panic’ despite their rejection by current scientific research. This paper reports an analysis of four survivors' accounts of the 1989 Hillsborough disaster to investigate if and how they used the term ‘panic’. Reference to ‘panic’ occurred frequently, but more detailed analysis found that their accounts did not match the classic criteria for ‘mass panic’ (e.g. uncontrolled emotion and selfish behaviour). Indeed, participants referred to ‘orderly’ behaviour, and cooperation, even when they said the threat of death was present. ‘Panic’ was therefore being used as a description of events that was not consistent. A discourse analysis of usage suggests that participants used ‘panic’ not only to convey feelings of fear and distress but also to apportion culpability towards the actions of the police who they considered responsible for the tragedy (as indeed recent independent research has confirmed). It is concluded that the term ‘panic’ is so deeply embedded in popular discourse that people may use it even when they have reason to reject its irrationalist implications. Alternative discourses that emphasise collective resilience in disasters are suggested

Microscopic dynamics in liquid metals: the experimental point of view

The experimental results relevant for the understanding of the microscopic dynamics in liquid metals are reviewed, with special regards to the ones achieved in the last two decades. Inelastic Neutron Scattering played a major role since the development of neutron facilities in the sixties. The last ten years, however, saw the development of third generation radiation sources, which opened the possibility of performing Inelastic Scattering with X rays, thus disclosing previously unaccessible energy-momentum regions. The purely coherent response of X rays, moreover, combined with the mixed coherent/incoherent response typical of neutron scattering, provides enormous potentialities to disentangle aspects related to the collectivity of motion from the single particle dynamics. If the last twenty years saw major experimental developments, on the theoretical side fresh ideas came up to the side of the most traditional and established theories. Beside the raw experimental results, therefore, we review models and theoretical approaches for the description of microscopic dynamics over different length-scales, from the hydrodynamic region down to the single particle regime, walking the perilous and sometimes uncharted path of the generalized hydrodynamics extension. Approaches peculiar of conductive systems, based on the ionic plasma theory, are also considered, as well as kinetic and mode coupling theory applied to hard sphere systems, which turn out to mimic with remarkable detail the atomic dynamics of liquid metals. Finally, cutting edges issues and open problems, such as the ultimate origin of the anomalous acoustic dispersion or the relevance of transport properties of a conductive systems in ruling the ionic dynamic structure factor are discussed.Comment: 53 pages, 41 figures, to appear in "The Review of Modern Physics". Tentatively scheduled for July issu

Effects of oxidized lipids (4,5 (E)-epoxy-2(E)-heptenal and 4,5 (E)-epoxy-2 (E) -decenal) and lysine reaction products on zinc and calcium utilization: assays in Caco-2 cells

The influence of the presence of brown products from the reaction between two oxidized lipids (4,5 (E)-epoxy-2(E)-heptenal, EH, and 4,5 (E)-epoxy-2 (E)-decenal, ED) and lysine (EH-L and ED-L) on zinc and calcium utilization was studied, and compared with a fructosyl-lysine mixture (F-L). Assays were carried out in Caco-2 cells grown in bicameral chambers. The Zn transported across the cell monolayer was significantly lower in the presence of the EH-L, ED-L and F-L samples, specially with EH-L. Significant decreases in Zn uptake were also observed, with no differences between samples. However, calcium transport was not modified. Thus, the assayed lipid-aminoacid brown products seem to have negative effects on Zn availability, whereas Ca availability appears to be unaffected.Se estudió la influencia de la presencia de productos obtenidos en la reacción de dos lípidos oxidados (4,5(E)-epoxy-2(E)- heptenal, EH, y 4,5(E)-epoxy-2(E)-decenal, ED) con el aminoácido lisina (EH-L y ED-L), sobre la absorción de zinc y calcio, comparándolos frente a una mezcla de fructosil-lisina (F-L). Los ensayos se realizaron con células Caco-2 sembradas en placas bicamerales. La adición de las muestras EH-L, ED-L y F-L al medio de cultivo supuso una reducción significativa en el Zn transportado a través de la monocapa de células, mucho más marcada ante la presencia de EH-L. También se redujo significativamente la captación celular de Zn, sin diferencias entre las distintas muestras ensayadas. Sin embargo, el transporte de Ca no se vio modificado. Por lo tanto, los productos pardos lípido-aminoacídicos ensayados parecen afectar negativamente la disponibilidad del Zn, sin tener efectos notables sobre la del Ca.Peer reviewe

Analysis of DDR1 function at epithelial cell contacts

Discoidin domain receptor 1 (DDR1) is a member of the receptor tyrosine kinase (RTK) family, and binds to collagen in the extracellular matrix (ECM). It therefore plays an important role in relaying information from outside the cell to intracellular components. Accordingly, DDR1 contributes to many cellular processes including migration and differentiation amongst others. In malignant states, cell-matrix interactions are often deregulated, resulting in the pro-invasive phenotype characteristic of tumours. Increased DDR1 expression is a negative prognostic marker for many cancers, however the molecular mechanisms are not fully understood. Interestingly, novel ligand-independent roles of DDR1 have recently emerged that potentially implicate the receptor at epithelial cell contacts. In this thesis, I show that during new keratinocyte contact formation, DDR1 is recruited after E-cadherin. In contrast to previous literature, DDR1 does not form a complex with E-cadherin, and distinct separate clusters of DDR1 and E-cadherin are observed at mature cell contacts. DDR1 depletion decreases the junctional E-cadherin and actin levels during cell contact formation. This phenotype is independent of actin recruitment to clustered E-cadherin receptors. Actin thin bundles are also visibly disrupted during contact formation with DDR1 depletion, which is further linked to a reduction in Rho-ROCK signalling and actomyosin contractility. Not only are the levels of phosphorylated myosin light chain and myosin phosphatase reduced, but ROCK1 levels are also reduced by DDR1 knockdown, suggesting that DDR1 has a regulatory role upstream of ROCK1. Preliminary experiments demonstrate potential binding between DDR1 and some members of the catenin protein family, however the significance of these interactions requires further investigation. Data collected from keratinocytes and a series of lung cancer cell lines, suggest that E-cadherin-mediated cell contacts inhibit collagen-mediated DDR1 activation, possibly by preventing DDR1 ligand accessibility. Overall, my results suggest that DDR1 stabilizes epithelial cell contacts through regulation of actomyosin contractility.Open Acces

Dynamic distributed monitoring of masonry railway bridges

Novel sensing technologies – for instance, fibre-optic Fibre Bragg Grating (FBG) sensors – offer engineers new means to study the dynamic distributed behaviour of complex structures, such as masonry arch bridges. These bridges, which are common features of many European transport networks, are often ageing structures, with complex histories of damage and repair work. Furthermore, their material properties and non-visible geometry may be challenging, if not impossible, to ascertain, creating uncertainty in the reliability of computational analyses. Particularly in light of the financial and environmental costs of their replacement, and the contributions that many of these bridges make to our shared architectural and industrial heritage, it is increasingly urgent to improve our understanding of the structural behaviour of masonry arch bridges under their real working loads. As these bridges undergo many cycles of loading, which may directly drive their deterioration, their response in working conditions is often more important than an understanding of their collapse behaviour, which can be studied using established methods such as limit state analysis. In this thesis, Structural Health Monitoring is used to gain new insights into the behaviour of masonry arch bridges and viaducts. Part 1 includes an initial study in which the outputs of simplified finite element models are compared against previously gathered FBG monitoring data, describing the response of a damaged masonry viaduct under applied train loading. It is found that the impact of damage on the viaduct response is primarily local, while common ‘single-point’ measurements, such as the crown vertical displacements, can be well matched by the simplified models. Furthermore, relative contributions from each of the main structural components of the viaduct, towards its overall SLS performance, are quantified. The remainder of the thesis is concerned with the monitoring of a case study structure: a recently repaired, skewed, masonry arch railway bridge. FBGs are used to monitor the dynamic behaviour of this bridge in detail – in particular, the in-plane strain response and the movements across cracks, including both opening and shearing movements across a key separation crack between the arch barrel and a spandrel wall. The sensitivity of these responses to a range of external variables – namely train speed, ambient temperature, time of day, and date – is presented. Trains travelling between approximately 80 and 90 mph are observed to induce a local strain response that is up to 15% higher than that of slower trains, although this effect is only present close to the arch crown, where loads are most concentrated at the extrados. The trend with time-of-day follows anticipated passenger behaviour. Trains at peak commute times result in higher magnitude and lower statistical spread in the bridge response; hence, comparing trains recorded at these times allows for variable passenger loading to be normalised. The in-plane flow of force throughout the skewed arch is also measured and visualised, using a novel ‘FBG strain rosette’ implementation that monitors the arch principal strains. These force flow distributions, experimentally mapped in detail for the first time for a skewed masonry arch, are highly consistent across many train events, suggesting a common response to different types of train loading. Separately, videogrammetry is used to measure the out-of-plane, vertical displacements of the arch. The distribution of these movements is used to fit a simplified beam model of the transverse bending component of the arch response. This structural monitoring is part of a broader, collaborative study, trialling a large range of different monitoring technologies at the case study bridge. A practical evaluation of these various technologies is presented in this thesis; despite the larger initial costs for an FBG system, the many measurement locations and high quality of data afforded by this technology meant that it compared favourably with more established approaches. In another collaboration, existing laser scan analysis methods for masonry arch bridges have been extended to skewed arches, and employed to study the historic, distributed deformation of this bridge. It is shown that the current deformed geometry could have been caused by small support movements at the obtuse corners of the arch abutments, which are consistent with past hypotheses in the literature regarding the behaviour of skewed masonry arch bridges. Much of this thesis is concerned with the analysis and interpretation of data collected through on-site monitoring of the case study bridge, carried out over a six-month period. Since this time, the FBG system at the bridge has been adapted for autonomous, remote sensing. The necessary improvements to the system are presented, covering both the equipment installed at the bridge and the accompanying data processing strategies, which now allow for automated data categorisation, analysis, and visualisation. Following this, the long-term data gathered to date is analysed. These data reveal further trends – in particular, linking the bridge response to ambient temperature. Lower temperatures lead to a larger magnitude response – potentially due to thermal contraction of the masonry causing existing cracks throughout the bridge to open, and thus increasing the potential for movements to occur under applied loads.I would like to acknowledge additional funding from Network Rail, and in kind support from AECOM, which supported the field monitoring components of my PhD research

The effect of temperature on subsonic jet noise

The noise levels produced by hot and cold subsonic jets have beefi measured using a convergent circular nozzle in an anechoic chamber. This report presents the effects of jet temperature on the sound power, the overall sound-pressure levels and the spectra of the jet noise. The results show an unexpected increase in noise with increasing jet temperature at low jet velocities. The possibility of this observation arising from sources upstream of the nozzle exit is considered and discounted. It is concluded that both the spectral shapes and the overall sound-pressure level of a hot jet are significantly affected by refraction of the sound by the jet. The overall sound-pressure levels have been correlated to form the basis of a method for the prediction of the noise from static jets

Interviews With HMA Directors: Dr. Jane Cocking

The Journal of Conventional Weapons Destruction is introducing a section dedicated to sharing the insights and experiences of those working in the field. This issue features HMA directors. Future issues will feature interviews with photojournalists, survivors, and veterans of the HMA community