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Background The epidemiology and outcome after out-of-hospital cardiac arrest (OHCA) varies across Europe. Following on from EuReCa ONE, the aim of this study was to further explore the incidence of and outcomes from OHCA in Europe and to improve understanding of the role of the bystander. Methods This prospective, multicentre study involved the collection of registry-based data over a three-month period (1st October 2017 to 31st December 2017). The core study dataset complied with the Utstein-style. Primary outcomes were return of spontaneous circulation (ROSC) and survival to hospital admission. Secondary outcome was survival to hospital discharge. Results All 28 countries provided data, covering a total population of 178,879,118. A total of 37,054 OHCA were confirmed, with CPR being started in 25,171 cases. The bystander cardiopulmonary resuscitation (CPR) rate ranged from 13% to 82% between countries (average: 58%). In one third of cases (33%) ROSC was achieved and 8% of patients were discharged from hospital alive. Survival to hospital discharge was higher in patients when a bystander performed CPR with ventilations, compared to compression-only CPR (14% vs. 8% respectively). Conclusion In addition to increasing our understanding of the role of bystander CPR within Europe, EuReCa TWO has confirmed large variation in OHCA incidence, characteristics and outcome, and highlighted the extent to which OHCA is a public health burden across Europe. Unexplained variation remains and the EuReCa network has a continuing role to play in improving the quality management of resuscitation. info:eu-repo/semantics/publishedVersion

Restricted stock awards carry upside and downside risks for CEOs. We follow a socio-cognitive perspective by suggesting that awards of restricted stock are viewed as potential gains or potential losses depending on each CEO's dominant regulatory focus. Regulatory focus, therefore, helps determine how a CEO responds to restricted stock awards. We also propose that the moderating effect of regulatory focus strengthens as firm complexity increases and as CEO tenure lengthens, because complexity and tenure both increase CEOs' reliance on heuristic information processing. Specifically, complexity restricts a CEO's cognitive capacity for thoughtful deliberation during decision making, and tenure affects a CEO's motivation to search for and process information thoroughly. We find general support for the hypotheses and discuss the implications of our findings for future research and practice.

The practicum is widely considered an integral component of pre-service training and an influential induction into the teaching profession. Yet, the practicum is fraught with challenges and literature identifies it to be overwhelming and stressful for pre-service teachers. Building on the work of Gray, Wright, and Pascoe (2017), this article explores the stressful side of practicum, recognising the way that stress is debilitating, impacting on students' ability to engage, effectively participate in, and grow through the experience. Field study data reveals the vulnerability five pre-service teachers from a Western Australian university experienced during practicum and the consequential lack of belonging and inadequate preparation they reported. These two key features are made more salient in the field of drama teaching where there are strong performative elements including not only the teaching of performance, but performance of the self. This research is key to better understanding the issues and challenges of the practicum so as to improve pre-service drama teachers’ experience and induction into the profession, building both solid foundations for practice, and a commitment towards drama teaching as a rewarding career.

A series of 3D soil–fluid coupled finite element analyses was conducted to examine the long-term tunnel behaviour of an old cast-iron cross passage in stiff London clay. In the proposed geotechnical FE model, an advanced critical state constitutive model was employed to simulate complex soil behaviour, whereas the details of the tunnel linings was simplified using shell elements. The computed time-dependent soil load derived from the geotechnical model was then applied to a structural finite element model where the details of the cross passage structure such as bolted-joints and tunnel segments were explicitly modelled. This proposed semi-coupled soil-structure model shows agreement against field observations and it was found in this particular case that the structural condition evaluated from the FE model is more critical than that of the conventional bedded ring method. Results show that the surface ground settlement is governed mainly by the twin tunnel construction and the presence of the cross passage does not increase the settlement. On the other hand, the construction of a cross passage affects the structural performance of the adjacent running tunnel in both short term (undrained) and long term (soil consolidation). In particular, the critical location is identified to be the tunnel segment adjacent to the opening at the axis level and its stresses and deformation increase with consolidation time.

The behaviour of cast-iron bolted tunnels in London underground railway network was investigated using the 3-D finite element (FE) method. A series of numerical simulations on a cast-iron segmental ring were conducted and its performance was compared against the analytical assessment used by London Underground Limited (LUL). Unlike the 2D plane model used in the LUL standard, the proposed FE model considered the 3D lining structural features (i.e. the geometry of the tunnel segment and the bolted joint) in a detailed manner. The behaviour of a cast-iron tunnel primarily goes through three stages: tunnel construction, soil loading and structural deterioration. At each stage, the influences on the tunnel behaviour such as external loading, soil-tunnel interaction were examined. Considering that, the proposed model thus resulted in more realistically structural performance in agreement with the field measurements.

Background More than a third of Ireland's population lives in a rural area, defined as the population residing in all areas outside clusters of 1500 or more inhabitants. This presents a challenge for the provision of effective pre-hospital resuscitation services. In 2012, Ireland became one of three European countries with nationwide Out-of-Hospital Cardiac Arrest (OHCA) register coverage. An OHCA register provides an ability to monitor quality and equity of access to life-saving services in Irish communities. Aim To use the first year of national OHCAR data to assess differences in the occurrence, incidence and outcomes of OHCA where resuscitation is attempted and the incident is attended by statutory Emergency Medical Services between rural and urban settings. Methods The geographical coordinates of incident locations were identified and co-ordinates were then classified as ‘urban’ or ‘rural’ according to the Irish Central Statistics Office (CSO) definition. Results 1798 OHCA incidents were recorded which were attended by statutory Emergency Medical Services (EMS) and where resuscitation was attempted. There was a higher percentage of male patients in rural settings (71% vs. 65%; p = 0.009) but the incidence of male patients did not differ significantly between urban and rural settings (26 vs. 25 males/100,000 population/year p = 0.353). A higher proportion of rural patients received bystander cardiopulmonary resuscitation (B-CPR) 70% vs. 55% (p ≤ 0.001), and had defibrillation attempted before statutory EMS arrival (7% vs. 4% (p = 0.019), respectively). Urban patients were more likely to receive a statutory EMS response in 8 min or less (33% vs. 9%; p ≤ 0.001). Urban patients were also more likely to be discharged alive from hospital (6% vs. 3%; p = 0.006) (incidence 2.5 vs. 1.1/100,000 population/year; p ≤ 0.001). Multivariable analysis of survival showed that the main variable of interest i.e. urban vs. rural setting was also independently associated with discharge from hospital alive (OR 3.23 (95% CI 1.43–7.31)). Conclusion There are significant disparities in the incidence of resuscitation attempts in urban and rural areas. There are challenges in the provision of services and subsequent outcomes from OHCA that occur outside of urban areas requiring novel and innovative solutions. An integrated community response system is necessary to improve metrics around OHCA response and outcomes in rural areas.

Patients exposed to bronchoscopes contaminated with Pseudomonas aeruginosa are at increased risk of pseudomonal infection. The optimal methods for management and mitigation of risk following exposure are controversial. This article describes a two-phase risk assessment following pseudomonal contamination of a family of 75 endoscopes, detected through routine surveillance and attributed to one endoscope washer-disinfector. An initial risk assessment identified 18 endoscopes as high risk, based on the presence of lumens used for irrigation or biopsy. Exposure was communicated to the patients' clinical teams and a further clinical risk assessment of the exposed patients was performed. No patients developed complications due to pseudomonal infection.

The physics of crack initiation in a polymer matrix composite are investigated by varying the modeling choices made in simulations and comparing the resulting predictions with high-resolution in situ images of cracks. Experimental data were acquired using synchrotron-radiation computed tomography (SRCT) at a resolution on the order of 1 pm, which provides detailed measurement of the location, shape, and size of small cracks, as well as the crack opening and shear displacements. These data prove sufficient to discriminate among competing physical descriptions of crack initiation. Simulations are executed with a high-fidelity formulation, the augmented finite element method (A-FEM), which permits consideration of coupled damage mechanisms, including both discrete cracks and fine-scale continuum damage. The discrete cracks are assumed to be nonlinear fracture events, governed by reasonably general mixed-mode cohesive laws. Crack initiation is described in terms of strength parameters within the cohesive laws, so that the cohesive law provides a unified model for crack initiation and growth. Whereas the cracks investigated are typically 1 mm or less in length, the fine-scale continuum damage refers to irreversible matrix deformation occurring over gauge lengths extending down to the fiber diameter (0.007 mm). We find that the location and far-field stress for crack initiation are predicted accurately only if the variations of local stress within plies and in the presence of stress concentrators (notches, etc.) are explicitly computed and used in initiation criteria; stress redistribution due to matrix nonlinearity that occurs prior to crack initiation is accounted for; and a mixed-mode criterion is used for crack initiation. If these factors are not all considered, which is the case for commonly used failure criteria, predictions of the location and far-field stress for initiation are not accurate.

An introduction to the special issue of the International Journal of Human-Computer Studies, which focuses on the perspectives on participation of the beginnings, middles and endings of participatory research in HCI, is presented. The HCI research community is increasingly engaging in participatory research that involves citizens, community members, multiple institutions, organizations and interested parties across the entire lifespan of projects. Participatory design projects also include the potential for integrating multiple voices and the challenge of aligning interested parties in design. The special issue includes discussions on reflexivity and reflection during the process of conducting participatory research in HCI.

The behaviour of cast-iron tunnel segments used in London Underground tunnels was investigated using the 3-D finite element (FE) method. A numerical model of the structural details of cast-iron segmental joints such as bolts, panel and flanges was developed and its performance was validated against a set of full-scale tests. Using the verified model, the influence of structural features such as caulking groove and bolt pretension was examined for both rotational and shear loading conditions. Since such detailed modelling of bolts increases the computational time when a full scale segmental tunnel is analysed, it is proposed to replace the bolt model to a set of spring models. The parameters for the bolt-spring models, which consider the geometry and material properties of the bolt, are proposed. The performance of the combined bolt-spring and solid segmental models are evaluated against a more conventional shell-spring model.

Takotsubo cardiomyopathy (TTC) is an acute heart failure syndrome classically characterized by hypocontractile apical and midventricular regions of the left ventricle, with a compensatory hypercontractile base. Available data support the hypothesis that TTC and atypical TTC-like disorders are primarily induced by catecholaminergic overstimulation, with epinephrine playing a crucial role. Knowledge from the available preclinical models should be used to guide the development of potential clinical trials in the most severe cases, where rates of acute morbidity and mortality are highest, and also to prevent recurrence in susceptible individuals.

High resolution Synchrotron Radiation Computed Tomography (SRCT) has been used to capture fibre damage progression in a carbon–epoxy notched [90/0]s laminate loaded to failure. To the authors knowledge this provides the first direct in situ measurement of the accumulation of fibre fractures for a high performance material under structurally relevant load conditions (i.e. fractures within the bulk of an essentially conventional engineering laminate). A high level of confidence is placed in the measurements, as the failure processes are viewed internally at the relevant micromechanical length-scales, as opposed to previous indirect and/or surface-based methods. Whilst fibre breaks are the dominant composite damage mechanism considered in the present work, matrix damage, such as transverse ply cracks, 0? splits and delaminations, were also seen to occur in advance of extensive fibre breaks. At loads where fibre break density levels were significant, splitting and delamination were seen to separate the central 0? ply in the near notch region from the 90? plies. Fibre breaks were initially observed in isolated locations, consistent with the stochastic nature of fibre strengths. The formation of clusters of broken fibres was observed at higher loads. The largest clusters observed consisted of a group of eleven breaks and a group of fourteen breaks. The large clusters were observed at the highest load, at sites with no prior breaks, indicating they occurred within a relatively narrow load range. No strong correlation was found between the location of matrix damage and fibre breaks. The data achieved has been made available online at www.materialsdatacentre.com for ongoing model development and validation.

Synchrotron radiation-computed tomography (SRCT) has been used to observe in situ damage growth and enable micromechanical damage characterization in [90/0]s carbon fibre-epoxy composite samples loaded in uniaxial tension to stresses ranging from 30% to 90% of the nominal failure stress. A three dimensional finite element model has been constructed to predict crack opening displacements and shear displacements in the 0 degrees plies resulting from thermal residual stress imposed during autoclave cure and from the application of mechanical load. Of particular interest is the demonstration of SRCT as a technique to enable direct, in situ, 3-D, non-destructive damage quantification to assist model development and provide model validation. In addition it has been identified that SRCT has the potential for full field analysis of strain re-distributions during damage growth.

X-ray computed laminography (CL) with synchrotron radiation is used to investigate fracture in carbon fibre–epoxy laminates. CL allows for high-resolution (∼1 μm) imaging of laterally extended objects. Whilst artefacts inherent to CL data reduce image quality compared with computed tomography (CT), imaging regions of interest in large planar samples greatly increases the engineering applicability. High-resolution in situ three-dimensional analysis of structural failure is therefore achievable at levels that would be impossible via CT or any other volume-imaging methods.

The inhomogeneity of alginate gel beads prepared by an external diffusion method has been characterised using spatially resolved nuclear magnetic resonance or “magnetic resonance imaging” (MRI) and transmission electron microscopy (TEM). The beads exhibited various degrees of inhomogeneity although reducing the length of exposure to the gelling bath and the presence of non-gelling ions decreased gel inhomogeneity. In order to gain information regarding the gastro-intestinal functionality of these beads for in vivo applications, they were exposed to simulated gastro-intestinal conditions. The increased polymer concentration at the edge of the beads was shown to persist throughout our gastro-intestinal model despite the centre of the bead becoming progressively more porous in nature. The porosity of the alginate gels has been quantified by image analysis of transmission electron micrographs and shown to depend on both location within the bead and gastro-intestinal conditions. We suggest that such changes in porosity of these alginate beads during simulated gastro-intestinal conditions may make these an attractive option for controlled delivery applications in vivo.

This paper examines principal and agent networks. We focus on networks because business research has placed far greater emphasis on the agency problem at the individual level. Our interest is in exploring the agency relationship at the group or network level. There are many variables at the group or network level which are absent when analyzing agency relationships at the individual level. Traditional theories of finance and economics do not adequately address or explain a host of behaviors that are inherent in human interactions that constitute organizational life. We include a sociological or behavioral approach in understanding this complex relationship. Using cohesiveness and shared goals as antecedents, we develop a theoretical model that predicts a range of relationship outcomes between principals and agents, as well as their impact on organizational goals. We explain that a range of relationships – including conflict, domination, exploitation, collaboration, and cooperation – is possible when networks of principals and agents interact. We argue that the social context is a key determinant of the relationship between actors in a network, and it has an important role in impacting cohesiveness and goal mutuality. The degree of cohesiveness within and between networks, and the extent to which goals are shared or are in conflict are the principal predictor variables we examine. We posit that cohesiveness and shared goals are necessary and sufficient conditions for agency problems between networks to be alleviated. Both necessary and sufficient conditions need to be met in order to overcome the problems of agency. The relationships we examine through the model include cooperation, collaboration, domination, opportunism, exploitation, and conflict. We present a number of propositions that theorize on the nature of the agency relationship and their impact on organizational goals. Implications for research and practice are also discussed.

This paper presents a three step approach to improve safety in the field of interactive systems. The approach combines, within a single framework, previous work in the field of barrier analysis and modelling, with model based design of interactive systems. The approach first uses the Safety Modelling Language to specify safety barriers which could achieve risk reduction if implemented. The detailed mechanism by which these barriers behave is designed in the subsequent stage, using a Petri nets-based formal description technique called Interactive Cooperative Objects. One of the main characteristics of interactive systems is the fact that the user is deeply involved in the operation of such systems. This paper addresses this issue of user behaviour by modelling tasks and activities using the same notation as for the system side (both barriers and interactive system). The use of a formal modelling technique for the description of these three components makes it possible to compare, analyse and integrate them. The approach and the integration are presented on a mining case study. Two safety barriers are modelled as well as the relevant parts of the interactive system behaviour. Operators’ tasks are also modelled. The paper then shows how the integration of barriers within the system model can prevent previously identified hazardous sequences of events from occurring, thus increasing the entire system safety.

We explore the impact of CEO tenure on returns to shareholders arising from acquisition announcements. Further, we consider the value added for shareholders when the board of directors is composed in such a way as to enhance vigilance. In the absence of a vigilant board, CEO tenure is positively associated with performance at low to moderate levels of tenure, and negatively associated with performance when tenure further rises to substantial levels. In the presence of a vigilant board, however, shareholder interests can be advanced even at high levels of CEO tenure.

In this work, we examine the effects of outside board monitoring on acquisition outcomes in a setting of limited ownership control structure (within manager-controlled firms). We also analyze the effects of outside directors on acquisition outcomes in the context of significant ownership control structures (within owner-controlled and owner–manager-controlled firms). Our findings support the substitution hypothesis. That is, outside board monitors influence the economic outcomes of acquisitions of manager-controlled enterprises, but not the outcomes of owner-controlled or owner–manager-controlled firms.

A computerised Stroop colour-naming task was used to measure concerns about weight, shape, and eating in bulimia nervosa. Two versions of the computerised Stroop were compared, a voice-activated and a button-pressing-activated programme. Bulimia nervosa patients were significantly slower in colour naming shape- and weight-related words than their female age-matched controls. The button-pressing computerised Stroop was both more sensitive and more accurate at measuring colour-naming speeds than the voice-activated version. When the bulimia nervosa group were divided according to their Eating Attitudes Test (EAT) scores, those who showed extreme pathological attitudes to weight and shape were significantly slower in colour naming size words and in food disruption scores than those with a lesser degree of psychopathology. The computerised Stroop might be useful as a diagnostic tool and in the assessment of the effectiveness of therapy for the individual patient.

Background Total kidney volume (TKV) is an approved early prognostic marker of progression in autosomal dominant polycystic kidney disease. The approval of tolvaptan for patients with rapid disease progression in Europe requires accurate patient stratification. Current methods of TKV measurement rely on manual segmentation which is time consuming, restricting its clinical use. To address this important clinical challenge we report the development and performance of a semi-automated method (Sheffield TKV tool) to measure TKV in patients with this disease. Methods 1.5T MRI scans were acquired (Siemens Avanto) in 61 adult patients with autosomal dominant polycystic kidney disease. Manual segmentation of the kidneys was performed on T2 true fast imaging with steady state precession MRI. Computational semi-automated segmentation methods were tested in a subgroup of ten patients and the optimum method used in all 61 cases to measure TKV (mL). Manual and semi-automated results were compared by Bland–Altman analyses. Processing time for manual and semi-automated methods were recorded. Findings Our cohort consisted of 29 men and 32 women (mean age 45 years, SD 14). Estimated GFR (eGFR) in patients within 1 month of the MRI ranged between 32 and 138 mL/min. TKV measured by manual segmentation ranged between 258 and 3680 mL. The Sheffield TKV tool performed optimally for calculating TKV, reporting accurate results in 80% of cases compared with manual TKV. Inaccuracies were associated with erroneous inclusion of blood vessels, the renal hilum, or leakage into neighbouring tissues, and overall were more frequent in smaller kidneys. Processing time for TKV with the Sheffield TKV tool was 2–5 min compared with 20–30 min for manual segmentation. Interpretation We describe a new rapid, semi-automated method for measuring TKV on MRI which should be a useful tool for evaluating patients with autosomal dominant polycystic kidney disease. We plan to optimise MRI acquisition sequences and extract the renal hilar volume to improve performance of the Sheffield TKV tool and validate it in another population with autosomal dominant polycystic kidney disease, with the ultimate aim of using it in clinical practice. Funding Insigneo (Institute for in silico medicine) bursary (from Sheffield Teaching Hospitals NHS Foundation Trust), National Institute for Health Research.

In this paper, we discuss agency theory in the context of the individual principal and agent, and also in the context of the organization and its groups. Agency theory is examined in the context of goal orientation, obligation and reciprocity, risk, and self-interest. We offer propositions given agency theory’s assumptions. We also extend agency theory and offer alternative propositions based on a relaxing of agency theory’s assumptions. In relaxing the assumptions of agency theory, insights from outside the agency literature, specifically from behavioral theories are used. Implications of agency theory and the extension of this theory are also discussed in relation to outcomes associated with economic exchanges.

The bacteriophage T4 AsiA protein inhibits transcription from host and phage early promoters and is required, along with the T4 MotA protein, for activation of phage middle promoters. During infection, AsiA is found in a tight association with the sigma70 subunit of RNA polymerase. We show that AsiA binds rapidly to free sigma70 at either 4 degrees C or 30 degrees C to form an AsiA-sigma70 complex that with core efficiently reconstitutes the AsiA-inhibited RNA polymerase. In contrast, AsiA does not inhibit transcription after a 15 minute incubation with RNA polymerase holoenzyme at 4 degrees C, and at 30 degrees C an incubation of several minutes is required to inhibit most of the polymerase. We show that the heat step needed for AsiA is not the formation of an active AsiA protein. However, it is consistent with the momentary dissociation of holoenzyme to give free sigma70 and core. Our results indicate that AsiA is either unable to access holoenzyme directly or does so very slowly. Efficient generation of the AsiA-inhibited RNA polymerase requires that AsiA first binds to free sigma70 and then the AsiA-sigma70 complex binds to core to form the Asi-A-inhibited polymerase.

Function allocation is a central component of systems engineering and its main aim is to provide a rational means of determining which system-level functions should be carried out by humans and which by machines. Such allocation, it is assumed, can take place early in design life cycle. Such a rational approach to work design sits uneasily with studies of work practice reported in the ACI and CSCW literature. In this paper we present two case studies of work in practice. The first highlights the difference between functional abstractions used for function allocation decision making and what is required to make those functions work in practice. The second highlights how practice and technology can co-evolve in ways that change the meanings of functions allocated early in design. The case studies raise a number of implications for function allocation. One implication is that there is a need for richer representations of the work context in function allocation methods. Although some progress has been made in function allocation methodologies, it is suggested that the method of Contextual Design might offer useful insights. A second implication is that there is a need for better theories of work to inform function allocation decision making. Activity Theory is considered as a possible candidate since it incorporates a cultural-historical view of work evolution. Both Contextual Design and Activity Theory challenge assumptions that are deeply embedded in the human factors and systems engineering communities. In particular, that functions and tasks are an appropriate unit of analysis for function allocation.

In this paper, we describe an approach to allocation of function that makes use of scenarios as its basic unit of analysis. Our use of scenarios is driven by a desire to ensure that allocation decisions are sensitive to the context in which the system will be used and by insights from economic utility theory. We use the scenarios to focus the attention of decision makers on the relative costs and benefits of developing automated support for the activities of the scenario, the relative impact of functions on the performance of the operator's primary role and on the relative demands placed on an operator within the scenario. By focussing on relative demands and relative costs, our method seeks to allocate the operator's limited resources to the most important and most productive tasks within the work system, and to direct the effort of the design organization to the development of automated support for those functions that deliver the greatest benefit for the effective operation of the integrated human–machine system.

In this paper, we examine agency theory’s presumptions of self-interest, opportunistic behavior, and the notion of the “economic man” (or woman). We contend that the application of agency theory’s presumptions to the firm may imply high costs, competitive disadvantage, and high firm risk. We suggest that agency theory’s presumptions may not contribute to the interests of the principal, agent, or other stakeholders. Alternatively, we discuss socioeconomic theories’ presumptions of enlightened self-interest, trustworthy behavior, and the possibility of the noneconomic person. We argue that the extension of socioeconomic theories to the firm may imply low costs, competitive advantage, and low firm risk. We contend that the socioeconomic presumptions may contribute to the interests of various stakeholders.

Samples of bovine serum from uninfected and African trypanosomes-infected animals were tested before and after γ-irradiation, using three sandwich enzyme-linked immunosorbent assays (ELISA). Each test system utilized a different monoclonal antibody, reputedly allowing the specific detection of conserved-invariant cytoplasmic antigens of trypanonosomes, T. congolense , T. vivax , and T. brucei , respectively. Results have identified two groups of samples. The first contained samples where there were unequivocal ELISA results indicating positivity and negativity, for non-irradiated samples. In this group, irradiation had no effect on the diagnostic sensitivity of the assays. All samples shown to be positive before irradiation remained positive and those shown to be negative, remained negative. There was, however, a statistically significant reduction in signal in each of the ELISAs following irradiation. The second group contained samples identified before irradiation as flanking the diagnostic negative/positive threshold of OD ≥0.05. These showed a negative bias after irradiation of the order of OD −0.01, which was shown to be statistically significant by paired t -statistics. Without correction of the given diagnostic negative/positive threshold, bovine sera with OD values around the threshold were expected to deliver more false negative test results upon irradiation. This was confirmed when serological data were compared with parasitological findings; where three times more false negative test results were found from irradiated serum samples. Consequently, for this group of irradiated bovine samples tested by ELISA, the re-adjustment of the diagnostic negative/positive threshold of the ELISAs using defined irradiated serum samples is recommended; otherwise, the frequency of false negative results might be increased.

In this study, we argue that share price reaction to a firm's capital expenditure decisions depends critically on the market's assessment of the quality of its investment opportunities. We postulate that announcements of increases (decreases) in capital expenditures positively (negatively) affect the stock prices of firms with valuable investment opportunities. Contrarily, we predict that announcements of increases (decreases) in capital spending negatively (positively) affect the share prices of firms without such opportunities. Our empirical results are generally consistent with these predictions. Overall, empirical evidence supports our conjecture that it is the quality of the firm's investment opportunities rather than its industry affiliation which determines the share price reaction to its capital expenditure decisions.

Approximately 30% of the UK population have been characterised as suffering, to some extent, from computer anxiety, showing either physiological, cognitive, or negatively affective reactions when working with computers. In this study, the relationship between computer anxiety and self-ratings of mood change was investigated. Mood was measured either by a computerized form of visual analog scales or by an identical test administered by paper-and-pencil. Positive mood change was manipulated by a modified Velten-type Mood Induction Procedure (VMIP, Velten, 1968) administered via a computer. Undergraduate student volunteers (40 males and 68 females) completed visual analog mood scales before and after the VMIP. The correlation between self-ratings of mood and the computer anxiety scores was significantly greater in the computer compared with the paper-and-pencil groups. Computer anxiety related to measured mood when the mood measurements were collected using the computerized procedure but not the paper procedure. The implications of these findings for the clinical application of computerized mood assessment are discussed.

This paper describes a method of presenting structured audio messages, earcons, in parallel so that they take less time to play and can better keep pace with interactions in a human-computer interface. The two component parts of a compound earcon are played in parallel so that the time taken is only that of a single part. An experiment was conducted to test the recall and recognition of parallel compound earcons as compared to serial compound earcons. Results showed that there are no differences in the rates of recognition between the two groups. Non-musicians are also shown to be equal in performance to musicians. Some extensions to the earcon creation guidelines of Brewster, Wright and Edwards are put forward based upon research into auditory stream segregation. Parallel earcons are shown to be an effective means of increasing the presentation rates of audio messages without compromising recognition rates.

Internally oriented business units, externally oriented business units, and businesses with dual emphasis (which are internally and externally oriented) are analyzed with respect to their performance. The results of the empirical investigation reveal that the internally oriented and the externally oriented businesses have not achieved competitive advantage and are underperformers. The results also portray that the businesses with dual emphasis have achieved competitive advantage and perform well.

In the past, examinations of the strategy-performance relationship have focused on samples from the industrial sector. This study, based on Porter's (1980) generic strategy framework, theoretically evaluates three propositions which may be used to extend this work to the retail sector. This article examines the unique forces affecting the relationship between strategy and performance within the retailing industry. Based on prior research, the authors hypothesize that in terms of both financial performance and operating performance, retailers employing multiple strategies to attain competitive advantage will outperform those using a singular approach.

Background: The treatment of Acanthamoeba keratitis has been increasingly successful as diagnoses are made earlier. The authors investigated features of the disease and prognosis in a consecutive series of 15 patients who were treated within 1 month of initial symptoms. Methods: A database of patients with Acanthamoeba infection presenting between March 1984 and March 1992 was analyzed. The recognition, presenting features, culture methods, results, and treatment of the early cases were reviewed to determine the reasons for a good outcome. Results: Recognition depended on perineural infiltrates (11/15), uveitis (10/15), limbitis (14/15), and infiltrated epithelium; 6 of 15 patients had epithelial defects, but only 3 of 15 had ring infiltrates or ulcers. Epithelial biopsy was culture-positive in 12 of 15 patients. Most (11/15) patients needed only two anti-amebal drugs. One patient only required penetrating keratoplasty for uncontrolled disease. The final visual acuity was at least 6/12 in all patients who had been treated within 1 month of first symptoms, whereas only 17 (53%) of 32 eyes of patients who presented after 1 month achieved a visual acuity of 6/12. Conclusions: Subtle diagnostic signs, supported by comprehensive microbiologic investigation, justify the immediate instigation of specific antiamebal therapy. Treatment within 1 month of onset results in a lower morbidity and a good visual outcome.

Background: The mechanism of chronic progressive conjunctival cicatrization in mucous membrane pemphigoid is not well understood, and current therapy is often of limited use. Rapid progression of cicatrization follows exacerbations of clinical inflammation, and the investigation of immune mechanisms related to disease activity may provide a clue for more effective therapeutic strategies. Methods: The authors undertook an immunohistochemical study, using monoclonal and polyclonal antibodies in glycol methacrylate-embedded tissues, of epibulbar conjunctival biopsy specimens obtained from 20 patients with ocular cicatricial pemphigoid and from 12 matched healthy controls. The study patients were classified according to the ocular disease activity as acute ulcerative (n = 4), subacute (n = 8), and chronic (n = 8). Results: The composition of the subepithelial cellular infiltrate varied with disease activity. Acute disease was characterized by an abundance of macrophages and neutrophils. The number of T lymphocytes was significantly raised in all the disease groups, but were most marked in subacute disease. Of the T-cell subsets, there were more CD8- than C134-positive cells observed, except in acute disease where there were equal numbers. Only approximately 5% of the T cells in all disease groups were activated as demonstrated by expression of interleukin-2 receptor. There was increased expression of major histocompatibility complex class II (MHC II) molecules on macrophages, fibroblasts, and other cells in all the groups. The number of B cells and natural killer cells was not increased. Staining for the fibrogenic cytokines, transforming growth factor-β (TGF-β), platelet-derived growth factor, and basic fibroblast growth factor was found in both pemphigoid patients and control persons, but the intensity of TGF-β staining was significantly greater in acute disease. Conclusions: The composition of the cellular infiltrate in the bulbar conjunctiva depends on clinical disease activity. The numbers of neutrophils and macrophages seem to reflect clinical disease activity. Fibrogenic cytokines, especially TGF-β, may play an important role in the formation of conjunctival scar tissue.

In this article theoretical and empirical explorations that have addressed the question, Whose interests do top managers pursue? are synthesized and grouped under two categories. Based on the review of the literature, three propositions are tested on two groups of organizations—mutual insurers and stock insurers. The results of the study lend support the premise that top executives do not necessarily act in the best interests of owners.

Study: Penetrating keratoplasty (PK) was undertaken between 1985–1991 at Moorfields Eye Hospital in 13 eyes (19 PKs) of 11 patients who developed Acanthamoeba keratitis. Infection was ultimately controlled in all cases. Retrospective analysis was undertaken to establish risk factors for PK. Six eyes were quiet and 7 had uncontrolled infection at the time of keratoplasty. The outcome for these was compared. Complications: Complications included cataract in 50% of quiet eyes and 100% of inflamed eyes. Intumescent cataract resulted in glaucoma requiring drainage surgery in 4 eyes. Graft rejection episodes occurred in 50% of quiet eyes, but were treated aggressively and did not cause graft failure. Results: Graft survival was excellent for quiet eyes, but was compromised by recurrent infection in inflamed eyes and 6 patients were regrafted. Survival compared poorly with grafting for active herpetic or bacterial keratitis, indicating that early diagnosis and treatment are essential for adequate control of this disease.

A strong case has been made for iterative design, that is, progressing through several versions of a user interface design using feedback from users to improve each prototype. One obstacle to wider adoption of this approach is the perceived difficulty of obtaining useful data from users. This paper argues that quantitative experimental methods may not be practical at early stages of design, but a behavioural record used in conjunction with think-aloud protocols can provide a designer with the information needed to evaluate an early prototype in a cost-effective manner. Further, it is proposed that a method for obtaining this data can be specified which is straightforward enough to be used by people with little or no training in human factors. Two studies are reported in which trainee designers evaluated a user interface by observing a user working through some set tasks. These users were instructed to think aloud as they worked in a procedure described as “cooperative evaluation”. The instruction received by the designers took the form of a brief how-to-do-it manual. Study 1 examines the effectiveness of the trainee designers as evaluators of an existing bibliographic database. The problems detected by each team were compared with the complete set of problems detected by all the teams and the problems detected by the authors in a previous and more extensive evaluation. Study 2 examined the question of whether being the designer of a system makes one better or worse at evaluating it and whether designers can predict the problems users will experience in advance of user testing.

The involvement of endogenous opioids in control of human food intake and appetite was investigated in a double-blind placebo-controlled study using a single, 2.5 mg oral dose of the opioid receptor antagonist, nalmefene. Ratings of the pleasantness of the smell and the taste, but not the appearance, of a number of foods was significantly lower in nalmefene-treated subjects. The magnitude of this effect was greater in food items independently rated as highly palatable. Caloric intake of a buffet-style meal was 20% lower in nalmefene-treated subjects, with the proportional reduction in intake of individual food items also depending on their palatability. These results lend further support to recent suggestions that opioids are involved in reward-related aspects of ingestion.

Lid isolates of Staphylococcus aureus and coagulase-negative staphylococci (CNS) from controls (12 S. aureus and 110 CNS) and from patients with blepharitis (17 S. aureus and 171 CNS) were tested for production of alpha, beta, delta, epsilon, and previously undescribed hemolytic toxins, because toxin production has been implicated as a cause of blepharoconjunctivitis. The electrolyte content of agar media required for toxin production was first investigated. Alpha-lysin was found to be produced by all isolates of S. aureus colonizing lids of normal controls and patients with blepharitis, but by none of 281 CNS isolates. A new toxin was identified, having low molecular weight (5 kd), produced by one CNS strain isolated from a blepharitic lid. It was produced on basic nutrient agar that lacked sodium but contained glucose, which inhibited production of alpha-lysin. It hemolyzed rabbit and sheep erythrocytes and, surprisingly, was neutralized by polyclonal antiserum to alpha-lysin. This may explain occasional reports of alpha-lysin production by CNS. The overall results do not support a hypothesis of hemolytic toxin production by staphylococci as a general cause of blepharitis.

This study sought to determine whether major increases in firm size, achieved through acquisitions, result in greater chief executive officer (CEO) compensation, given manager versus owner control. A second issue addressed is whether the type of firm—single industry or multiple industry—plays a role in the linkage between acquisition activity and additional compensation. Other variables included in the analysis were CEO tenure and profitability. Annual observations from 1979 through 1986 of 50 firms that had engaged in acquisition activity form the basis of the study. Findings reveal that acquisitions, after allowing 1 year for the full impact of the merger to be felt, led to significant increases in CEO compensation for both owner- and manager-controlled firms. Also, it was found that manager-controlled firms gave their CEOs further rewards for additional years on the job, regardless of performance, while owner-controlled firms were found to reward more on the basis of performance.