Showing papers by "Brunel University London published in 2007"

Dynamic capabilities: A review and research agenda

Abstract: The notion of dynamic capabilities complements the premise of the resource-based view of the firm, and has injected new vigour into empirical research in the last decade Nonetheless, several issues surrounding its conceptualization remain ambivalent In light of empirical advancement, this paper aims to clarify the concept of dynamic capabilities, and then identify three component factors which reflect the common features of dynamic capabilities across firms and which may be adopted and further developed into a measurement construct in future research Further, a research model is developed encompassing antecedents and consequences of dynamic capabilities in an integrated framework Suggestions for future research and managerial implications are also discussed

CMS physics technical design report, volume II: Physics performance

Abstract: CMS is a general purpose experiment, designed to study the physics of pp collisions at 14 TeV at the Large Hadron Collider (LHC). It currently involves more than 2000 physicists from more than 150 institutes and 37 countries. The LHC will provide extraordinary opportunities for particle physics based on its unprecedented collision energy and luminosity when it begins operation in 2007. The principal aim of this report is to present the strategy of CMS to explore the rich physics programme offered by the LHC. This volume demonstrates the physics capability of the CMS experiment. The prime goals of CMS are to explore physics at the TeV scale and to study the mechanism of electroweak symmetry breaking--through the discovery of the Higgs particle or otherwise. To carry out this task, CMS must be prepared to search for new particles, such as the Higgs boson or supersymmetric partners of the Standard Model particles, from the start-up of the LHC since new physics at the TeV scale may manifest itself with modest data samples of the order of a few fb−1 or less. The analysis tools that have been developed are applied to study in great detail and with all the methodology of performing an analysis on CMS data specific benchmark processes upon which to gauge the performance of CMS. These processes cover several Higgs boson decay channels, the production and decay of new particles such as Z' and supersymmetric particles, Bs production and processes in heavy ion collisions. The simulation of these benchmark processes includes subtle effects such as possible detector miscalibration and misalignment. Besides these benchmark processes, the physics reach of CMS is studied for a large number of signatures arising in the Standard Model and also in theories beyond the Standard Model for integrated luminosities ranging from 1 fb−1 to 30 fb−1. The Standard Model processes include QCD, B-physics, diffraction, detailed studies of the top quark properties, and electroweak physics topics such as the W and Z0 boson properties. The production and decay of the Higgs particle is studied for many observable decays, and the precision with which the Higgs boson properties can be derived is determined. About ten different supersymmetry benchmark points are analysed using full simulation. The CMS discovery reach is evaluated in the SUSY parameter space covering a large variety of decay signatures. Furthermore, the discovery reach for a plethora of alternative models for new physics is explored, notably extra dimensions, new vector boson high mass states, little Higgs models, technicolour and others. Methods to discriminate between models have been investigated. This report is organized as follows. Chapter 1, the Introduction, describes the context of this document. Chapters 2-6 describe examples of full analyses, with photons, electrons, muons, jets, missing ET, B-mesons and τ's, and for quarkonia in heavy ion collisions. Chapters 7-15 describe the physics reach for Standard Model processes, Higgs discovery and searches for new physics beyond the Standard Model

Antecedents and outcomes of abusive supervision: test of a trickle-down model.

Abstract: The authors examined antecedents of abusive supervision and the relative importance of interactional and procedural justice as mediators of the relationship between abusive supervision and the work outcomes of affective organizational commitment and individual- and organization-directed citizenship behaviors. Data were obtained from subordinate-supervisor dyads from a telecommunication company located in southeastern China. Results of moderated regression analysis revealed that authoritarian leadership style moderated the relationship between supervisors' perceptions of interactional justice and abusive supervision such that the relationship was stronger for supervisors high rather than low in authoritarian leadership style. In addition, results of structural equation modeling analysis revealed that subordinates' perceptions of interactional but not procedural justice fully mediated the relationship between abusive supervision and the work outcomes. Implications for future investigations of abusive supervision are discussed. Copyright 2007 by the American Psychological Association.

DNA repair is limiting for haematopoietic stem cells during ageing

Abstract: Accumulation of DNA damage leading to adult stem cell exhaustion has been proposed to be a principal mechanism of ageing. Here we address this question by taking advantage of the highly specific role of DNA ligase IV in the repair of DNA double-strand breaks by non-homologous end-joining, and by the discovery of a unique mouse strain with a hypomorphic Lig4(Y288C) mutation. The Lig4(Y288C) mouse, identified by means of a mutagenesis screening programme, is a mouse model for human LIG4 syndrome, showing immunodeficiency and growth retardation. Diminished DNA double-strand break repair in the Lig4(Y288C) strain causes a progressive loss of haematopoietic stem cells and bone marrow cellularity during ageing, and severely impairs stem cell function in tissue culture and transplantation. The sensitivity of haematopoietic stem cells to non-homologous end-joining deficiency is therefore a key determinant of their ability to maintain themselves against physiological stress over time and to withstand culture and transplantation.

Robust $H_{\infty}$ Control for Networked Systems With Random Packet Losses

Abstract: In this paper, the robust Hinfin control problem Is considered for a class of networked systems with random communication packet losses. Because of the limited bandwidth of the channels, such random packet losses could occur, simultaneously, in the communication channels from the sensor to the controller and from the controller to the actuator. The random packet loss is assumed to obey the Bernoulli random binary distribution, and the parameter uncertainties are norm-bounded and enter into both the system and output matrices. In the presence of random packet losses, an observer-based feedback controller is designed to robustly exponentially stabilize the networked system in the sense of mean square and also achieve the prescribed Hinfin disturbance-rejection-attenuation level. Both the stability-analysis and controller-synthesis problems are thoroughly investigated. It is shown that the controller-design problem under consideration is solvable if certain linear matrix inequalities (LMIs) are feasible. A simulation example is exploited to demonstrate the effectiveness of the proposed LMI approach.

Influence of concentric and eccentric resistance training on architectural adaptation in human quadriceps muscles

Abstract: Studies using animal models have been unable to determine the mechanical stimuli that most influence muscle architectural adaptation. We examined the influence of contraction mode on muscle architectural change in humans, while also describing the time course of its adaptation through training and detraining. Twenty-one men and women performed slow-speed (30 degrees /s) concentric-only (Con) or eccentric-only (Ecc) isokinetic knee extensor training for 10 wk before completing a 3-mo detraining period. Fascicle length of the vastus lateralis (VL), measured by ultrasonography, increased similarly in both groups after 5 wk (Delta(Con) = +6.3 +/- 3.0%, Delta(Ecc) = +3.1 +/- 1.6%, mean = +4.7 +/- 1.7%; P < 0.05). No further increase was found at 10 wk, although a small increase (mean approximately 2.5%; not significant) was evident after detraining. Fascicle angle increased in both groups at 5 wk (Delta(Con) = +11.1 +/- 4.0%, Delta(Ecc) = +11.9 +/- 5.4%, mean = 11.5 +/- 3.2%; P < 0.05) and 10 wk (Delta(Con) = +13.3 +/- 3.0%, Delta(Ecc) = +21.4 +/- 6.9%, mean = 17.9 +/- 3.7%; P < 0.01) in VL only and remained above baseline after detraining (mean = 13.2%); smaller changes in vastus medialis did not reach significance. The similar increase in fascicle length observed between the training groups mitigates against contraction mode being the predominant stimulus. Our data are also strongly indicative of 1) a close association between VL fascicle length and shifts in the torque-angle relationship through training and detraining and 2) changes in fascicle angle being driven by space constraints in the hypertrophying muscle. Thus muscle architectural adaptations occur rapidly in response to resistance training but are strongly influenced by factors other than contraction mode.

CMS physics technical design report: Addendum on high density QCD with heavy ions

Abstract: This report presents the capabilities of the CMS experiment to explore the rich heavy-ion physics programme offered by the CERN Large Hadron Collider (LHC). The collisions of lead nuclei at energies , will probe quark and gluon matter at unprecedented values of energy density. The prime goal of this research is to study the fundamental theory of the strong interaction ? Quantum Chromodynamics (QCD) ? in extreme conditions of temperature, density and parton momentum fraction (low-x).This report covers in detail the potential of CMS to carry out a series of representative Pb-Pb measurements. These include bulk observables, (charged hadron multiplicity, low pT inclusive hadron identified spectra and elliptic flow) which provide information on the collective properties of the system, as well as perturbative probes such as quarkonia, heavy-quarks, jets and high pT hadrons which yield tomographic information of the hottest and densest phases of the reaction.

Severity of arterial hypoxaemia affects the relative contributions of peripheral muscle fatigue to exercise performance in healthy humans

Abstract: We examined the effects of hypoxia severity on peripheral versus central determinants of exercise performance. Eight cyclists performed constant-load exercise to exhaustion at various fractions of inspired O2 fraction (FIO2 0.21/0.15/0.10). At task failure (pedal frequency < 70% target) arterial hypoxaemia was surreptitiously reversed via acute O2 supplementation (FIO2 = 0.30) and subjects were encouraged to continue exercising. Peripheral fatigue was assessed via changes in potentiated quadriceps twitch force (DeltaQ(tw,pot)) as measured pre- versus post-exercise in response to supramaximal femoral nerve stimulation. At task failure in normoxia (haemoglobin saturation (SpO2) approximately 94%, 656 +/- 82 s) and moderate hypoxia (SpO2) approximately 82%, 278 +/- 16 s), hyperoxygenation had no significant effect on prolonging endurance time. However, following task failure in severe hypoxia (SpO2) approximately 67%; 125 +/- 6 s), hyperoxygenation elicited a significant prolongation of time to exhaustion (171 +/- 61%). The magnitude of DeltaQ(tw,pot) at exhaustion was not different among the three trials (-35% to -36%, P = 0.8). Furthermore, quadriceps integrated EMG, blood lactate, heart rate, and effort perceptions all rose significantly throughout exercise, and to a similar extent at exhaustion following hyperoxygenation at all levels of arterial oxygenation. Since hyperoxygenation prolonged exercise time only in severe hypoxia, we repeated this trial and assessed peripheral fatigue following task failure prior to hyperoxygenation (125 +/- 6 s). Although Q(tw,pot) was reduced from pre-exercise baseline (-23%; P < 0.01), peripheral fatigue was substantially less (P < 0.01) than that observed at task failure in normoxia and moderate hypoxia. We conclude that across the range of normoxia to severe hypoxia, the major determinants of central motor output and exercise performance switches from a predominantly peripheral origin of fatigue to a hypoxia-sensitive central component of fatigue, probably involving brain hypoxic effects on effort perception.

Benefits of and barriers to involving users in medical device technology development and evaluation.

Abstract: Objectives: This study investigated the benefits of and barriers to user involvement in medical device technology development and evaluation.Methods: A structured review of published literature in peer-reviewed journals was conducted.Results: This literature review revealed that the main benefits of user involvement were an increased access to user needs, experiences, and ideas; improvements in medical device designs and user interfaces; and an increase in the functionality, usability, and quality of the devices. On the other hand, resource issues, particularly those of time and money were found the key impediments to involving users in the development and evaluation of medical device technologies. This study also has categorized both the benefits of and barriers to user involvement.Conclusions: The involvement of users in medical device technology development and evaluation requires resources, which are limited; however, this involvement is essential from both users and manufacturers perspectives.

A critical review of forms of corporate community involvement: from philanthropy to partnerships

Abstract: The paper offers a critical review of the forms of corporate community involvement (CCI) including: corporate philanthropy, benefaction, patronage, sponsorship and cause related marketing (CRM) and partnership. It discusses the differences/similarities and compares the limitations of the transactional forms of interaction with the latest form of partnership. The paper suggests that the form of partnership represents a shift towards a non-linear business model of CCI, that is moving away from an outcome towards a process orientation. Three factors are identified conditioning the successful implementation and sustainability of partnerships which are linked with the previous limitations of transactional approaches of interaction. Finally, the paper puts forward three propositions in order for partnerships to: (1) contribute to the increase of institutional trust among organisations and across sectors; (2) assist in balancing the dynamics across the sectors and (3) appreciate the process of interaction as a source of benefits. Copyright © 2007 John Wiley & Sons, Ltd.

The interactivity effect in multimedia learning

Abstract: The aim of this study was to determine whether the addition of interactivity to a computer-based learning package enhances the learning process. A sample of 33 (22 male and 11 female) undergraduates on a Business and Management degree used a multimedia system to learn about the operation of a bicycle pump. The system consisted of a labelled diagram of the pump, followed by a description of twelve stages in its operation. The sample was randomly divided into two groups who used either an interactive (I) or a non-interactive (NI) version involving both images and text. The I system differed from the NI system by the incorporation of control of pace, self-assessment questions and an interactive simulation. Students then undertook two different types of tests to assess their learning: one designed to evaluate their memory by recalling facts from the lesson, and another designed to assess their understanding through solving novel diagnostic problems. Students using the I system outperformed those using the NI system in the problem-solving test, and needed less time to complete both memory and problem-solving tests. This result is consistent with the hypothesis that interactive systems facilitate deep learning by actively engaging the learner in the learning process. This suggests that educational designers who seek to foster deep learning (as opposed to mere factual recall) should adopt the incorporation of interactivity as a design principle.

Exercise-induced cardiac troponin T release: a meta-analysis

Abstract: Purpose: Cardiac troponin T (cTnT) is a highly specific marker of myocardial damage and used clinically in the diagnosis of acute myocardial infarction (AMI). Release of cTnT has been demonstrated in several small studies after endurance exercise. The purpose of this study was to explore, using a meta-analytic approach, the incidence of postexercise cTnT release after endurance exercise. Methods: Articles identified via Pubmed, SportDiscus, and Embase (1997-2006) searches using the key words cardiac troponin T, cTnT, cardiac biomarkers, and exercise; a search of bibliographies; and consultation with experts in the field were entered into a random-effects meta-analysis. We identified 26 relevant studies (1120 cases). Age, gender, and body mass of participants, as well as exercise mode and duration, were explored as possible moderator variables with meta-regressions. Results: Postexercise cTnT levels exceeded the assay detection limit in 47% of participants (95% CI = 39-56%). The detection of postexercise cTnT after cycling events was approximately half that of running events (27 vs 52%, P = 0.042). The detection of postexercise cTnT decreased slightly as event duration increased (P = 0.022) and mean body mass decreased (P = 0.0033). Postexercise detection of cTnT was not affected by age (P= 0.309) and was only slightly higher for studies with more males in the sample (P = 0.028). Conclusions: Exercise-induced cTnT release is apparent in almost half of the endurance athletes who have been studied to date. Relatively heavy individuals competing in shorter endurance events, primarily running marathons, are slightly more likely to demonstrate elevated cTnT postexercise than other athletes. These data are useful for clinicians evaluating athletes with cTnT elevations after competitive endurance exercise events.

Synchronization in an array of linearly stochastically coupled networks with time delays

Abstract: In this paper, the complete synchronization problem is investigated in an array of linearly stochastically coupled identical networks with time delays. The stochastic coupling term, which can reflect a more realistic dynamical behavior of coupled systems in practice, is introduced to model a coupled system, and the influence from the stochastic noises on the array of coupled delayed neural networks is studied thoroughly. Based on a simple adaptive feedback control scheme and some stochastic analysis techniques, several sufficient conditions are developed to guarantee the synchronization in an array of linearly stochastically coupled neural networks with time delays. Finally, an illustrate example with numerical simulations is exploited to show the effectiveness of the theoretical results.

Electronic transformation of government in the U.K.: a research agenda

Abstract: This paper presents the findings of an exploratory research project into future e-Government (electronic Government) initiatives. The Virtual Institute for Electronic Government Research (VIEGO) project aimed at identifying and further developing the research agenda of e-Government based on a solid practical ground. As such, the paper offers a novel methodology in identifying the road map for future e-Government initiatives based on a series of workshops organised around the U.K. hosting a mixture of stakeholders involving both academics and practitioners. The analysis of the VIEGO workshops depicted that an e-Government research agenda involves a combination of social, technological and organisational issues at both governmental and individual citizen level, ultimately driven by empirical case-based experience and active participation in e-Government processes. Unlike other propositions for the future of e-Government offered in the e-Government literature, it raised research questions not only originated from an analysis of e-Government literature but also on the outcome of brainstorming, reflections and contemplations throughout the duration of the project.

Evidence of a broad structure at an invariant mass of 4.32GeV/c2 in the reaction e+e-→π+π-ψ(2S) measured at BABAR

Abstract: The authors measure the cross section for the process e{sup +}e{sup -} {yields} {pi}{sup +}{pi}{sup -}{psi}(2S) from threshold up to 8 GeV center-of-mass energy using events containing initial-state radiation, produced at the PEP-II e{sup +}e{sup -} storage rings The study is based on 298 fb{sup -1} of data recorded with the BABAR detector A structure is observed in the cross-section not far above threshold, near 432 GeV This structure is not compatible with the Y(4260) previously reported by this experiment A single resonance is adequate to describe the cross-section in the low-energy region (< 57 GeV)

Financial constraints to innovation in the UK: evidence from CIS2 and CIS3

Abstract: The role of financial factors as constraints to innovation in the UK is explored using data on individual returns to the second and third Community Innovation Surveys. It is found that financial factors do impact upon innovative activity and that impact is more severe in higher tech sectors and for smaller enterprises. These results extend but largely confirm the results in the extant literature by using a different approach to the standard cash flow based method, encompassing a wider class of investment phenomena (innovation rather than just RD) and exploiting a new data base.

An Analysis of Corporate Social Responsibility, Corporate Identity and Ethics Teaching in Business Schools

Abstract: Recent events have raised concerns about the ethical standards of public and private organisations, with some attention falling on business schools as providers of education and training to managers and senior␣executives. This paper investigates the nature of, motivation and commitment to, ethics tuition provided by the business schools. Using content analysis of their institutional and home websites, we appraise their corporate identity, level of engagement in socially responsible programmes, degree of social inclusion, and the relationship to their ethics teaching. Based on published research, a schema is developed with corporate identity forming an integral part, to represent the macro-environment, parent institution, the business school and their relationships to ethics education provision. This is validated by our findings.

Consumers online: intentions, orientations and segmentation

Abstract: Purpose – The purpose of this paper is to examine the purchase intentions of online retail consumers, segmented by their purchase orientation.Design/methodology/approach – An e‐mail/web survey was addressed to a consumer panel concerning their online shopping experiences and motivations, n=396.Findings – It is empirically shown that consumer purchase orientations have no significant effect on their propensity to shop online. This contradicts the pervasive view that internet consumers are principally motivated by convenience. It was found that aspects that do have a significant effect on purchase intention are prior purchase and gender.Research limitations/implications – There are two limitations. First, the sample contained only UK internet users, thus generalisations about the entire population of internet users may be questionable. Second, in our measurement of purchase intentions, we did not measure purchase intent per se.Practical implications – These findings indicate that consumer purchase orientati...

Robust impulsive synchronization of coupled delayed neural networks with uncertainties

Abstract: This paper investigates the synchronization scheme of coupled neural networks with time delays. The coupling function, which can be linear or nonlinear, is subject to uncertainties in the network. By utilizing the stability theory for impulsive functional differential equations, several new criteria are obtained to ensure the robust synchronization of coupled networks via impulsive control. Furthermore, an estimation of the predicted stable region is derived to facilitate the design of the control gain. Finally, numerical simulations are presented to demonstrate the effectiveness of our results.