Lifetime Constraints for Late Dark Matter Decay

We consider a class of late-decaying dark-matter models, in which a dark matter particle decays to a heavy stable daughter of approximately the same mass, together with one or more relativistic particles which carry away only a small fraction of the parent rest mass. Such decays can affect galactic halo structure and evolution, and have been invoked as a remedy to some of the small scale structure-formation problems of cold dark matter. There are existing stringent limits on the dark matter lifetime if the decays produce photons. By considering examples in which the relativistic decay products instead consist of neutrinos or electron-position pairs, we derive stringent limits on these scenarios for a wide range of dark matter masses. We thus eliminate a sizable portion of the parameter space for these late decay models if the dominant decay channel involves Standard Model final states.Comment: 13 pages, 7 figures. Replaced to match published version. Discussion expanded. References added. Accepted by Phys. Rev

Clinical and financial consequences of setting up an asthma clinic at St. Luke’s Hospital

The effects of setting up an asthma clinic were assessed in an audit study. A comparison was made between the quality and quantity of medication used by patients before and after attending the asthma clinic. The number and severity of exacerbations during a six month period before and a six month period after attending were also assessed. The cost of treatment before and after was also calculated. In 14% of patients, occupational factors, drugs or underlying lung disease were significant contributors to asthma. The number of acute episodes of severe asthma were reduced from 98 to 47, with hospital admissions falling from 26 to 1. Pulmonary function (%FEV1) improved in the group as a whole with the number of patients having their best FEV above 80% improving from 44 to 71. In spite of the expense of high cost drugs and the running costs of the clinic there were substantial savings largely from the reduced number of hospital admissions. The calculated annual cost fell from Lm 22,769 to Lm 10,654.peer-reviewe

Searching for Dark Matter at the LHC with a Mono-Z

We investigate a mono-Z process as a potential dark matter search strategy at the LHC. In this channel a single Z boson recoils against missing transverse momentum, attributed to dark matter particles, $\chi$, which escape the detector. This search strategy is related, and complementary to, monojet and monophoton searches. For illustrative purposes we consider the process $q\bar{q} -> \chi\chi Z$ in a toy dark matter model, where the Z boson is emitted from either the initial state quarks, or from the internal propagator. Among the signatures of this process will be a pair of muons with high pT that reconstruct to the invariant mass of the Z, and large amounts of missing transverse energy. Being a purely electroweak signal, QCD and other Standard Model backgrounds are relatively easily removed with modest selection cuts. We compare the signal to Standard Model backgrounds and demonstrate that, even for conservative cuts, there exist regions of parameter space where the signal may be clearly visible above background in future LHC data, allowing either new discovery potential or the possibility of supplementing information about the dark sector beyond that available from other observable channels.Comment: 11 pages, 13 figure

Speedy Techniques to Evaluate Seismic Site Effects in Particular Geomorphologic Conditions: Faults, Cavities, Landslides and Topographic Irregularities

The ground motion that can be recorded at the free surface of a terrain is the final result of a series of phenomena that can be grouped into three fundamental typologies: the source mechanism, the seismic wave propagation till the bedrock interface below the investigated site and the site effects (Fig. 1). The first two features define the kind of seismic input whereas the third represents all modifications that can occur as a consequence of the interaction between seismic waves and local characteristics of the investigated site. The physical and mechanical properties of terrains as well as their morphologic and stratigraphic features appreciably affect the characteristics of the ground motion observed at the surface. The whole process of modifications undergone by a given seismic input in terms of amplitude, frequency content and duration, as a consequence of local characteristics, is generally termed the “local seismic response”. It is indeed well known that the spectral composition of a seismic event is modified first during the source-bedrock path (attenuation function), and second, when the seismic input interacts with the soft terrains layered between the bedrock and the free surface (Fig. 1a). This latter effect, significantly changes the spectral content so that it is extremely important for estimating the final input to which all structures built in the study area will be subjected.peer-reviewe

A review of the literature on human behaviour in dwelling fires

Most fire-related injuries and fatalities in the UK, and other parts of the world, continue to occur during fires in the home – incidents where it is acknowledged that human factors play a contributing role. Yet the field of fire safety lacks an up-to-date review of the literature on human behaviour during fires in domestic spaces. Given there is now a growing body of work looking at human behaviour in dwelling fires, a review of the literature in this area is timely. Drawing from published studies, this paper sets out what is currently known about human behaviour in dwelling fires and highlights the differences that appear to exist between these spaces and what is known and accepted about human behaviour in public, commercial and industrial spaces. This paper then goes on to consider the nature of “fire risk”, arguing that much of the work in this area continues to conflate, or fails to recognise the existence of, different types of risk profiles, instead considering fire risk as a single type of risk, based mainly on factors related to fatalities. However, research findings point towards fire risk as at least three separate forms: the risk of a fire occurring, the risk of fire injury and the risk of fire fatality. By drawing together the literature on human behaviour in dwelling fires this paper argues that those who survive dwelling fires cannot be considered as “near miss fatalities”, but instead must be treated as a separate and distinct group

From data to difference – considering the application of a large-scale database of human behaviour in accidental dwelling fires

This paper outlines six newly developed insight themes designed as a tool to engage the United Kingdom Fire and Rescue Service (FRS) in a discussion about the importance of human behaviour in accidental dwelling fires (ADFs), a subject that has received limited attention compared to the study of human behaviour in other environments. Central to a wider research programme focussing on the public's perspective of an ADF is an important project, named LIFEBID (Lessons in Fire & Evacuation Behaviour in Dwellings). LIFEBID will create the world's first large-scale database of human behaviour in ADFs. The LIFEBID database will generate new data comprising hundreds (and potentially) thousands of survey responses from members of the public who have directly experienced an ADF. The insight themes provide a means to engage with FRS stakeholders about the relevance of the work for them. Within this paper the insight themes consider the importance of this subject for the UK FRS, which is a key stakeholder, both in the research development and the application of its findings. The insight themes allow logical presentation of emerging and potential applications in a format that is easily understood

Myocarditis and intramural coronary vasculitis in polyarteritis nodosa: an unusual treatable form of heart failure

We describe an uncommon cardiac presentation of polyarteritis nodosa. A 68-year-old woman, with a history of fatigue, weight loss, and myalgia of the lower extremities, was admitted for congestive heart failure. Coronary arteries were normal. Endomyocardial biopsy showed active lymphocytic myocarditis with associated intramural small vessels necrotizing vasculitis. The overexpression of TLR-4 and the negativity for myocardial viruses suggested an immune mediated mechanism of cardiac damage. These histologic findings associated to weight loss >4 kg not due to dieting or other factors, myalgias, and polyneuropathy, were consistent with the diagnosis of polyarteritis nodosa. Immunosuppressive treatment, consisting of cyclophosphamide and prednisolone, led to a significant improvement of cardiac function. Polyarteritis nodosa can be the cause of unexplained heart failure due to myocarditis and intramural vessels vasculitis. Its recognition is crucial to obtain a cardiac recovery with a tailored immunosuppressive treatment

Recollection of flame height and smoke volume in domestic fires

When a domestic fire occurs, how well do people perceive and recall the fire hazards they encounter? Although much research has been conducted on threat or risk perception and memory for threatening stimuli, to the authors' knowledge no studies have systematically tested how well people perceive and recall the threat stimulus in a fire context. This is an important topic given that domestic fires are usually the main source of fire-related injuries and deaths, and human behaviour is believed to play a significant role in such outcomes. Moreover, eyewitness testimonies play a significant role in subsequent fire, insurance and coroner investigations. The current study – part of wider research on human behaviour in domestic fires, called LIFEBID – sought to address the gap in knowledge by conducting an online experiment testing participants' (a) memories for the size of the flames and smoke witnessed in a mock kitchen fire, and (b) reported willingness to engage with the fire hazards. Participants' behaviours and attitudes in relation to other risky activities and control over events were also measured. The results revealed that accurate recollections of flame height and smoke volume can be obtained from members of the public, in certain cases. Accuracy was negatively impacted when the flames and smoke witnessed were larger in size. The size of the fire hazards also had an impact on participants' willingness to engage with the hazards, moderating the number who stated that they could have successfully extinguished the flames or would have entered the room with the smoke. Although there were signs that many participants recognised the risks posed by the larger hazards, a not inconsiderable number were still willing to engage with them. Being someone who takes greater risks in a health/safety domain and believing in one's ability to control what happens to oneself did not explain this finding. There is a clear need for a deeper investigation into people’s perceptions of fire hazards in a domestic fire context and their associated behaviours and fire outcomes

Multistress characterization of fault mechanisms in aerospace electric actuators

The concept behind the More Electric Aircraft (MEA) is the progressive electrification of on-board actuators and services. It is a way to reduce or eliminate the dependence on hydraulic, mechanical and the bleed air/pneumatic systems and pursue efficiency, reliability and maintainability. This paper presents a specialised test rig whose main objective is to assess insulation lifespan modelling under various stress conditions, especially investigating the interaction between ageing factors. The test set-up is able to reproduce a multitude of environmental and operational conditions at which electric drives and motors, used in aerospace applications, are subjected. It is thus possible to tailor the test cycle in order to mimic the working cycle of an electrical motor during real operation in aircraft application. The developed test-rig is aimed at projecting the technology readiness to higher levels of maturity, in the context of electrical motors and drives for aerospace applications. Its other objective is to validate and support the development of a comprehensive insulation degradation model