Skip to main content

WRAP - latest items

WRAP: Warwick Research Archive Portal: No conditions. Results ordered -Date Deposited.

Aim: To assess the cost-effectiveness of LUCAS-2, a mechanical device for cardiopulmonary resuscitation (CPR) as compared to manual chest compressions in adults with non-traumatic, out-of-hospital cardiac arrest.
Methods: We analysed patient-level data from a large, pragmatic, multi-centre trial linked to administrative secondary care data from the Hospital Episode Statistics (HES) to measure healthcare resource use, costs and outcomes in both arms. A within-trial analysis using quality adjusted life years derived from the EQ-5D-3L was conducted at 12-month follow-up and results were extrapolated to the lifetime horizon using a decision-analytic model.
Results: 4471 patients were enrolled in the trial (1652 assigned to the LUCAS-2 group, 2819 assigned to the control group). At 12 months, 89 (5%) patients survived in the LUCAS-2 group and 175 (6%) survived in the manual CPR group. In the vast majority of analyses conducted, both within-trial and by extrapolation of the results over a lifetime horizon, manual CPR dominates LUCAS-2. In other words, patients in the LUCAS-2 group had poorer health outcomes (i.e. lower QALYs) and incurred higher health and social care costs.
Conclusion: Our study demonstrates that the use of the mechanical chest compression device LUCAS-2 represents poor value for money when compared to standard manual chest compression in out-of-hospital cardiac arrest.

This paper proposes a Simulated Annealing variant for optimization problems in which the solution quality can only be estimated by sampling from a random distribution. The aim is to nd the solution with the best expected performance, as for example is typical for problems where solutions are evaluated using a stochastic simulation. Assuming Gaussian noise with known standard deviation, we derive a fully sequential sampling procedure and decision rule. The procedure starts with a single sample of the value of a proposed move to a neighboring solution and then continues to draw more samples until it is able to make a decision to finally accept or reject the move. Under constraints of equilibrium detailed balance at each draw, we find a decoupling between the acceptance criterion and the choice of the rejection criterion. We derive a universally optimal acceptance criterion in the sense of maximizing the acceptance probability per sample,
and thus the e ciency of the optimization process. We show that the choice of the move rejection criterion depends on expectations of possible alternative moves and propose a simple and practical (albeit more empirical) solution that still preserves detailed balance. An empirical evaluation shows that the resulting approach is indeed more efficient than several previously proposed Simulated Annealing variants.

Trans-Abdominal Preperitoneal Patch (TAPP) repairs for Recurrent Hernia (RH) is a technically demanding procedure. It has to be performed only by surgeons with extensive experience in the laparoscopic approach. The purpose of this study is to evaluate the surgical safety and the efficacy of TAPP for RH performed in a tutoring program by surgeons in practice (SP).

Many methods in Multi-Criteria Decision Analysis for choice problems rely on eliciting pairwise preference information in their attempt to e ciently identify the most preferred solution out of a larger set of solutions. That is, they repeatedly ask the decision maker which of two solutions is preferred, and then use this information to reduce the number of possibly preferred solutions until only one remains. However, if the solutions have a very similar value to the decision maker, he/she may not be able to accurately decide which solution is preferred. This paper makes two main contributions. First, it extends Robust Ordinal Regression to allow a user to declare indi erence in case the values of the two solutions do not di er by more than some personal threshold. Second, we propose and compare several heuristics to pick pairs of
solutions to be shown to the decision maker in order to minimize the number of interactions necessary.

Ultrasonic Rayleigh waves can be employed for the detection of surface breaking defects such as rolling contact fatigue and stress corrosion cracking. Electromagnetic Acoustic Transducers (EMATs) are well suited to this technique as they can directly generate Rayleigh waves within the sample without the requirement for wedges, and they are robust and inexpensive compared to laser ultrasonics. Three different EMAT coil types have been developed, and these are compared to assess their ability to detect and characterize small (down to 0.5 mm depth, 1 mm diameter) surface breaking defects in aluminium. These designs are: a pair of linear meander coils used in a pseudo-pulse-echo mode, a pair of focused meander coils also used in pseudo-pulse-echo mode, and a pair of focused racetrack coils used in pitch-catch mode. The linear meander coils are able to detect most of the defects tested, but have a much lower signal to noise ratio and give limited sizing information. The focused meander coils and the focused racetrack coils can detect all defects tested, but have the advantage that they can also characterize the defect sizes on the sample surface, and have a stronger sensitivity at their focal point. Measurements using all three EMAT designs are presented and compared for high resolution imaging of surface-breaking defects.

There seems to be an increasing problem with basic skills acquisition for young people in the UK. Lower levels of facility with literacy and numeracy than older generations are being reported, including for those with higher levels of education. In this article, we attribute the problem to prevalent fixed mindsets, resulting in a lack of attention to developing both narrative and scientific modes of thought in all learners, and also to the important affective domain: beliefs, attitudes and emotions. This can lead to the unintended exclusion of learners within certain subjects, based on their existing strengths and weaknesses.

We propose the development of a newly sensitive and inclusive approach, rooted in the use of both narrative and scientific modes of thoughts across all subject areas, developing growth mindsets, promoting academic resilience and using the 'growth zone model' explicitly with learners.

The recovery of ancient RNA from archaeological material could enable the direct study of micro-evolutionary processes. Small RNAs are a rich source of information because their small size is compatible with biomolecular preservation, and their roles in gene regulation make them likely foci of evolutionary change. We present here the small RNA fraction from a sample of archaeological barley generated using high-throughput sequencing that has previously been associated with localised adaptation to drought. Its microRNA profile is broadly similar to 19 globally distributed modern barley samples with the exception of three microRNAs (miRNA159, miRNA319, and miR396), all of which are known to have variable expression under stress conditions. We also found retrotransposon activity to be significantly reduced in the archaeological barley compared to the controls, where one would expect the opposite under stress conditions. We suggest that the archaeological barley's conflicting stress signals could be the result of long-term adaptation to its local environment.

There is great need for the widespread use of indoor gas monitors as modern hermetically-sealed domestic buildings increasingly suffer from indoor air pollution. However, neither modern technologies of gas sensors nor analytical instruments are ideally suited to this purpose. The problems of gas sensors are poor selectivity and the fact that normally they can detect only one gas, and analytical instruments suffer from their large size and high price. Therefore, the aim of the project is "to develop a novel gas sensor with low cost, low power consumption, high reliability, which can detect multiple gases with excellent selectivity" for indoor gas monitoring.

In the first part of the project, an SOI-CMOS micro-hotplate with a single crystal silicon (SCS) resistive heater was proposed, fabricated and characterised. The design obviates issues of traditional heater materials i.e. platinum is not CMOS compatible and polysilicon is not thermally stable due to its polycrystalline structure. The SCS micro-hotplate was found to have an ultra low power consumption of 11.6 mW to operate at 500°C, and an excellent reliability with less than 1% drift after 500 hour operation at 500°C.

In the second part, a novel temperature modulation technique for a carbon black/polymer composite sensor was theoretically derived based upon linear solvation and Fickian diffusion. The processing technique comprises only two steps; summing the off and on transient conductance signals from a temperature-stepped sensor, and subtracting the steady-state signal. The technique was demonstrated by applying to a carbon black/polyvinylpyrrolidone composite sensor employing the novel micro-hotplate. Identification of water. methanol and ethanol vapours was successfully demonstrated using the peak time of the resultant curve. Furthermore, quantification of those vapours was found to be possible using the height of the peaks, which was linearly proportional to the concentration.

In conclusion, a novel low-cost gas sensor has been realised that is capable of detecting more than one gas with a single sensing element and thermal modulation. This has the potential for commercial exploitation in the area of indoor air pollution monitoring.

The Caribbean's creative industries have contributed significantly to the global creative economy having crafted numerous musical genres, birthed countless Nobel laureates and award winning artists, as well as creating the blueprint for the many Caribbean festivals that take place worldwide. Still, despite its successes, the region has yet to realise its full potential. This thesis argues that brand plays a critical and strategic role in cultural production, distribution and consumption, and that it can ultimately further the development of the Caribbean's creative economy. Focusing on three of the region's core creative industries – music, festivals and fashion – the thesis uses data gathered from qualitative interviews and document analysis in order to gain a deeper understanding of 'brand', its uses and its influence within the regional economy. The thesis explores the dominant definitions of brand, the process of brand building, the role of the 'metabrand', as well as various themes intrinsic to these, including creativity, value and authenticity. This thesis also explores the concept of Brand Caribbean, by first defining its core features and then examining its relationship with national brands and cultural identities. The thesis also examines the region's current role within the global creative marketplace, as well as the challenges that currently impede its growth. This newfound understanding of both brand and Brand Caribbean offers a new sociocultural framework within which to evaluate the regional creative economy, and also presents new avenues for the region to negotiate a stronger position within the global market.

In this commentary, we reflect on the last decade of research in the field of neuromarketing and present a schematic illustration of the basic process of a typical neuromarketing study. We then identify three critical points of interest in this illustration that have not received enough discussion in neuromarketing-relevant literature, and which we consider to be somewhat problematic. These are the dominance of event-based designs in neuromarketing, the potential of alternative modalities in neuromarketing and the current focus on reverse inference in neuromarketing. We argue that, taken together, these points have substantive implications for the development of a more reflective neuromarketing, which in turn has greater potential to make a positive impact on marketing knowledge, marketing practice and public perceptions of marketing activity in general.

In general, the business ethics literature has treated the conceptual domains and outcomes of macro-level (industrial), meso-level (organizational), and micro-level (individual) ethical influence separately. However, this singular treatment ignores the synergies and tensions that can arise across these different types of ethical influence. Using sales as a research context, the current study argues that all three ethical frames of references are important in shaping employee behavior and performance and, as such, should be examined simultaneously. The findings show that industrial ethical climate and salesperson moral equity are positively associated with salesperson customer orientation. In addition, industrial and organizational ethical norms have a stronger joint effect on customer orientation than either ethical climate alone. More specifically, a more ethical organizational climate enhances the positive effects of the industrial ethical climate on customer orientation. Furthermore, whereas salesperson moral equity is significantly associated with salesperson customer orientation, strong moral equity beliefs in situations requiring adaptive selling result in weaker sales outcomes. This study concludes with a set of theoretical and actionable implications, as well as a discussion of future research avenues.

This article considers the position of international education, and the ways in which it 'borrows' performativity structures from the English education system. Utilising a recent Case Study and analysing Ralph Tabberer's personal reflections on it, the article outlines ways in which we can continue to learn from the socio-cultural dimensions of the English schooling system that are regularly utilised in an international educational context.

Carbon materials, including single-walled carbon nanotubes (SWNT) and graphene, have gained great interest in electrochemistry. The advantages of carbon electrodes include chemical stability, biocompatibility, low background currents and good electrical conductivity. With the increasing importance of carbon electrode materials for biological and energy application, the systematic investigation and new applications is mandatory.

SWNT networks, with different densities, are firstly investigated using microscale capillary electrochemical (EC) methods. Pristine high density (HD) SWNT networks are shown to exhibit more facile electron transfer (ET) for dopamine (DA) electro-oxidation and are less susceptible to blocking by reaction products when compared to low density (LD) SWNT networks. Acid treatment of SWNT networks results in an enhancement of electrode kinetics and a reduction in their susceptibility to surface fouling. Further, a comparison is made between SWNT electrodes, with different densities and a commercial screen printed carbon electrode (SPCE), for the oxidation of ferrocenecarboxylic acid (FcCOOH) in complex aqueous media (polyethylene glycol (PEG) and albumin), to mimic conditions in which diagnostic devices might be used. SWNTs exceed the performance of SPCEs, with a detection limit that is 3 orders of magnitude lower. Finally, a Ni(OH)2 nanoparticles (NPs) modified SWNT network is employed for the methanol oxidation reaction (MOR) and the ethanol oxidation reaction (EOR), showing improved ET processes with ~2.8 kA g-1 for MOR and ~3.7 kA g-1 for EOR, which are much higher than recent reports using other nanostructured catalysts.

A fundamental understanding of the structure-activity of "blistered" highly oriented pyrolytic graphite (HOPG), produced by electro-oxidation in HClO4, is obtained using scanning EC cell microscopy (SECCM) coupled with multi-microscopy techniques. The disordered sp2 carbon structure of the blister catalyzes the electro-oxidation of hydrazine compared to the basal surface. In this study, a potential sweep at each pixel of pre-defined scan area is recorded, providing potentiodynamic data with high resolution.

To demonstrate that the approaches are generally applicable, a fundamental study of the redox activity for Li2O2 product (toroidal and layer structure) in dimethyl sulfoxide (DMSO) non-aqueous media, is undertaken. A unique gel polymer organic electrolyte (polymer matrix, cross linker and organic electrolyte) is employed in a dual barrel nanopipette and the SECCM approach is carried out with cyclic voltammetry (CV) measurements performed at every pixel of a scan. The Li2O2 toroids outperforms the Li2O2 layer structure with a 9 times increase in the current response and ca. 80 % of charge efficiency. This work provides valuable information with regards to cathode materials for effective Li-air battery.

Conventional seismic-resistant structural systems are currently designed to develop a global sway plastic mechanism under strong earthquakes, which is achieved by allowing the development of controlled inelastic deformations in specific locations of main structural members such as beams, bases of columns and braces. Inelastic deformations in structural members result in damage and residual drifts, and therefore, in economic losses such as repair costs and downtime. Moreover, earthquake reconnaissance reports reveal large economic losses related to non-structural damage, e.g. failure of walls due to large storey drifts or failure of acceleration-sensitive equipment due to large peak floor accelerations. These losses highlight the need for resilient structures with the potential to remain intact after frequently occurred earthquakes and return to service within an acceptable short, if not immediate, time after strong rare earthquakes. Moreover, resilient structures should provide a very low probability of collapse (i.e. increased life safety) under very rare maximum considered earthquake.

Steel self-centering moment-resisting frames using post-tensioned beam-column connections are a promising class of resilient structures. They exhibit softening force-drift behaviour and eliminate inelastic deformations and residual drifts as the result of gap openings developed in beam-column interfaces and elastic post tensioned bars which clamp beams to columns and provide self-centering capability. Also, post tensioned connections use energy dissipation devices, which are activated when gaps open and can be easily replaced if damaged. Steel frames equipped with passive dampers are another class of resilient structures. Dampers provide supplemental damping to control drifts, and thus, provide an effective means to achieve economical designs with high performance.

The main goal of this PhD is to develop a seismic design and assessment procedure for steel self-centering moment-resisting frames (SC-MRFs) with viscous dampers within the framework of Eurocodes 3 and 8. To achieve this goal, nonlinear models of post-tensioned connections, able to capture the strength and stiffness deterioration due to local buckling, are developed. These models enable the assessment of the seismic behaviour of SC-MRFs with viscous dampers up to collapse with the aid of nonlinear dynamic analysis. A seismic design method, which incorporates a robust way to estimate rotation demands in post-tensioned connections, is then formulated. Different SC-MRFs with viscous dampers are designed using the proposed design procedure to study different design scenarios. The accuracy of the design procedure is evaluated through nonlinear dynamic analysis. In addition, the superior collapse resistance of SC-MRFs with viscous dampers is validated through incremental dynamic analysis. The thesis concludes with the implementation of an advanced probabilistic framework for direct economic seismic loss estimation and its application to confirm the potential of SC-MRFs with viscous dampers to significantly reduce economic seismic losses.

This paper concerns the approximation of probability measures on Rd with respect to the KullbackLeibler divergence. Given an admissible target measure, we show the existence of the best approximation, with respect to this divergence, from certain sets of Gaussian measures and Gaussian mixtures. The asymptotic behavior of such best approximations is then studied in the small parameter limit where the measure concentrates; this asympotic behaviour is characterized using Γ-convergence. The theory developed is then applied to understand the frequentist consistency of Bayesian inverse problems in finite dimensions. For a fixed realization of additive observational noise, we show the asymptotic normality of the posterior measure in the small noise limit. Taking into account the randomness of the noise, we prove a Bernstein-Von Mises type result for the posterior measure

The technology of wireless transformed societies and re-defined the nature of national and transnational communication when radio broadcasting to the public began in the early 1920s. This thesis focuses on the three main wartime radio stations (the BBC, Radiodiffusion and Radio Paris) broadcasting to and in France from June 1940 to November 1942. By studying the narratives of the broadcasting that lay at the heart of each radio station's politics, motivation, propaganda and interaction with the population at large, the thesis will attempt to give these radio stations the recognition that they deserve in the historiography of wartime France, and, in doing so, make a major contribution to knowledge on radio propaganda.

This thesis goes beyond existing literature by offering a comparative analysis of radio propaganda messages, thus deepening the understanding of the evolution of broadcasts in the context of the complex political and social impact of the war on the French population. The narratives reveal the political rhetoric and the perceived social norms during the German Occupation, as well as the exercise of power, which may be taken for granted. For each radio station, a key theme is identified as the overarching basis for analysis: food and the impact of food policy on families for the BBC; youth and its idealised role in the construction of a New France for Radiodiffusion; and youth and its perceived role in a German-dominated New Europe for Radio Paris.

Written and audio archives in England and France were consulted as the principal source for the research conducted. This research is limited in that the conclusions drawn are largely dependent on the material available to researchers, material which is incomplete and often piecemeal.

Information security breaches have serious consequences for companies. And information security breaches in the defence industry negatively impact national security. Selling information concerning industrial design, organisational strategic plans, customers, experts and other valuable information for monetary benefit, revenge, bribery and embezzlement are just some examples of the human dimension of information security.



Envelope  publications at warwick dot ac dot uk

Quick links