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Standardized measurement approach : is comparability attainable?
No full textRecently, the Basel Committee on Banking Supervision (BCBS) published a consultation paper that proposed a radical change to the methodologies permitted for estimating operational risk regulatory capital (ORRC). The Committee proposed replacing all existing approaches with a single new formula, the standardized measurement approach (SMA), which, it is claimed, will be simpler and promote comparability of estimated ORRC across banks. This proposal has, however, been widely criticized by practitioners and academics on both theoretical and practical grounds. Recent studies have demonstrated that, far from promoting comparability, the proposals have the potential to increase rather than reduce variability in the estimation of ORRC across banks. This paper adds to this critique by considering the practical issues of the consistency of operational loss data that are necessary for comparability to be observable. The paper concludes that comparability is not attainable as desired by the SMA proposal, not least because the collection of operational loss data will remain determined by individual bank rules and will not be based on agreed common standards. The paper discusses arguments made by academics and practitioners against the proposal and, finally, makes a suggestion to the BCBS that a comprehensive fundamental review, similar to that recently completed for market risk, should be undertaken for operational risk.40 page(s
Measuring leader behaviour : evidence for a “big five” model of leadership
No full textPurpose: The purpose of this paper is to provide evidence for a “leadership big five”, a model of leadership behaviour integrating existing theories of leadership and conceptually aligned with the most established model of personality, the big five. Such a model provides researchers and practitioners with a common language to describe leadership behaviour in a field with a plethora of leadership models. The model also describes a wider range of leadership behaviour than other models of leadership, and presents dimensions that correlate with important organisational outcomes as demonstrated in this study. Design/methodology/approach: In total, 1,186 employees completed the Voice Leadership 360, a survey designed to measure the leadership big five, collectively rating 193 managers from a range of different sectors and industries, using a 360-degree survey methodology. Findings: Confirmatory factor analyses and internal reliability analyses provide evidence for 22 lower-order factors of leadership behaviour that aggregate into five higher-order factors of leadership aligned with the big five personality descriptors. Further evidence for the validity of the model is indicated by significant correlations between 360-degree survey ratings and raters’ judgements of leaders’ personality, and significant correlations between 360-degree survey ratings and both work unit engagement levels and manager reports of work unit performance. Research limitations/implications: The cross-sectional design is the main limitation of the present study, limiting conclusions that changes in leadership behaviours will lead to changes in organisational outcomes. The primary research implications of this study include the support for an integrating model of leadership behaviour that aligns with a large body of psychological research, as well as the development of a survey that can be used for future exploration of the model. Practical implications: Practitioners may use the results of the study to rethink how they develop competency frameworks and measure leadership behaviour in organisation development contexts. This broad model of leadership and the familiarity of its dimensions could increase the effectiveness of behaviour change interventions, and the presented survey provides a reliable and valid tool for 360-degree assessments. Originality/value: The study provides evidence that leadership can be described in a structurally similar way to human personality. It presents a leadership model that consists of a broader range of leadership behaviours related to organisational outcomes compared with previous models of leadership.19 page(s
Comment on "Mycorrhizal association as a primary control of the CO2 fertilization effect"
No full textTerrer et al. (Reports, 1 July 2016, p. 72) used meta-analysis of carbon dioxide (CO₂) enrichment experiments as evidence of an interaction between mycorrhizal symbiosis and soil nitrogen availability. We challenge their database and biomass as the response metric and, hence, their recommendation that incorporation of mycorrhizae in models will improve predictions of terrestrial ecosystem responses to increasing atmospheric CO₂.2 page(s
Optimal time to enter a retirement village
No full textWe consider the financial planning problem of a retiree wishing to enter a retirement village at a future uncertain date. The date of entry is determined by the retiree’s utility and bequest maximisation problem within the context of uncertain future health states. In addition, the retiree must choose optimal consumption, investment, bequest and purchase of insurance products prior to their full annuitisation on entry to the retirement village. A hyperbolic absolute risk-aversion (HARA) utility function is used to allow necessary consumption for basic living and medical costs. The retirement village will typically require an initial deposit upon entry. This threshold wealth requirement leads to exercising the replication of an American put option at the uncertain stopping time. From our numerical results, active insurance and annuity markets are shown to be a critical aspect in retirement planning.20 page(s
Reconstructing ice-age palaeoclimates : quantifying low-CO₂ effects on plants
No full textWe present a novel method to quantify the ecophysiological effects of changes in CO₂ concentration during the reconstruction of climate changes from fossil pollen assemblages. The method does not depend on any particular vegetation model. Instead, it makes use of general equations from ecophysiology and hydrology that link moisture index (MI) to transpiration and the ratio of leaf-internal to ambient CO₂ (χ). Statistically reconstructed MI values are corrected post facto for effects of CO₂ concentration. The correction is based on the principle that e, the rate of water loss per unit carbon gain, should be inversely related to effective moisture availability as sensed by plants. The method involves solving a non-linear equation that relates e to MI, temperature and CO₂ concentration via the Fu-Zhang relation between evapotranspiration and MI, Monteith's empirical relationship between vapour pressure deficit and evapotranspiration, and recently developed theory that predicts the response of χ to vapour pressure deficit and temperature. The solution to this equation provides a correction term for MI. The numerical value of the correction depends on the reconstructed MI. It is slightly sensitive to temperature, but primarily sensitive to CO₂ concentration. Under low LGM CO₂ concentration the correction is always positive, implying that LGM climate was wetter than it would seem from vegetation composition. A statistical reconstruction of last glacial maximum (LGM, 21±1 kyr BP) palaeoclimates, based on a new compilation of modern and LGM pollen assemblage data from Australia, is used to illustrate the method in practice. Applying the correction brings pollen-reconstructed LGM moisture availability in southeastern Australia better into line with palaeohydrological estimates of LGM climate.11 page(s
Verification and applications of surface waves extracted from ambient noise
No full textEmpirical thesis.At foot of title page: ARC Centre of Excellence for Core to Crust Fluid Systems (CCFS) and GEMOC.Bibliography: pages 111-129.1. Introduction -- 2. Extracting EGF from ambient noise -- 3. Validating accuracy of Rayleigh wave dispersion extracted from ambient seismic noise via comparison with data from a Ground-Truth earthquake -- 4. On the accuracy of long-period Rayleigh waves extracted from ambient noise -- 5. 3D shear wave velocity model of US continent constructed from broadband ambient noise tomography -- 6. Accuracy of earthquake location based on group travel time of surface wave from ambient noise -- 7. Conclusion -- References.About a decade ago, it was shown that Empirical Green's Function (EGF) between two seismic stations can be extracted from cross-correlation of ambient seismic noise. Since then, studies based on ambient noise have become a method of choice among seismologists. Noise Cross-correlation Function (NCF) has been widely used for seismic tomography (known as ANT), monitoring velocity changes, calibrating earthquake location, and so on. Almost all of these studies are based on the assumption that accurate EGF can be extracted from cross-correlations of ambient noise. However, uncertainties of the dispersion measurements from ambient noise are still not clear. It is also not certain whether surface waves at periods longer than 50 s can be extracted from ambient noise recorded at portable seismic stations or whether the resulting dispersion measurements from ambient noise are accurate enough to image lithosphere and asthenosphere structures. This thesis is to address these questions. I investigate the accuracy of surface wave dispersion curves at both short (10-30 s) and long (50-250 s) periods from ambient noise. By comparing the waveforms and dispersion curves from ambient noise with those from earthquake data, I demonstrate that the dispersion measurements from surface waves extracted from ambient noise are as accurate as those from earthquake data. The dispersion measurements can be used in ambient noise tomography to provide complementary data, which can be used to constrain the lithospheric and asthenospheric structures.Furthermore, I demonstrate that broadband surface waves at 10-150 s period from ambient noise can be used to construct the 3D shear wave velocity structure from the surface down to 300 km depth in the USA. I calculate NCFs among all the US Aarray stations in US continent and extract broadband (10-150 s) Rayleigh wave phase velocities, and obtain phase velocity maps by inverting the broadband dispersion curves. Then, I build a new 3D shear wave velocity model of the lithosphere and asthenosphere structure by inverting the resulting phase velocity maps.Finally, I demonstrate that using EGFs from ambient noise, we can improve earthquake location and locate recorded historical earthquakes. Using a seismic array in central Australia, I test the accuracy of our location method using ambient noise. I find that, when the distribution of the remote station is good and the reference station is located less than 20 km away from the source, the location error is less than 2 km. I conclude that this method can be used to obtain ground truth event with location error equal or smaller than 2 km (GT2) in regions with sparsely distributed remote stations.Mode of access: World wide web1 online resource (xxvi, 129 pages) colour map
Virulence of functions of proteobacterial antimicrobial compound efflux (PACE) family of transport proteins
No full textTheoretical thesis.Includes bibliographical references.1. Introduction -- 2. Material and methods -- 3. Results -- 4. Discussion -- 5. Future research -- 6. Conclusion.Acinetobacter baumannii is a significant hospital-acquired pathogen due to its traits such as multidrug resistance. Multidrug efflux systems are one of the major causes of resistance to many antimicrobials in pathogenic bacteria. The multidrug efflux pumps in bacterial pathogens also play an important role in a range of cellular activities other than drug resistance, such as virulence, biofilm formation and the export of secondary metabolites. Recent data using mouse and insect larval models suggest that the novel multidrug efflux pump AceI may play an important role in animal colonization and virulence. This project investigated the potential virulence functions of the aceI gene by performing a range of assays including growth in human serum, attachment to biotic and abiotic surfaces and iron starvation. It was found that aceI is not required for the overall fitness of the AB5075-UW for the growth in laboratory media or for the survival of this strain under iron-limiting conditions. However, an aceI knockout strain was not viable for growth in 100% human serum. Therefore, aceI might play a role in providing resistance to a component of human serum. Furthermore, biofilm formation and quorum sensing studies also suggested potential involvement of aceI in the pathophysiology of AB5075-UW.1 online resource (v, 55, xii pages : illustrations
Malware architects and rational choice: a case study analysis of three cyber-offenders
No full textTheoretical thesis.Bibliography: pages 96-107.Chapter One. Introduction -- Chapter Two. Literature review -- Chapter Three. Research methods -- Chapter Four. Robert Tappan Morris -- Chapter Five. David Lee Smith -- Chapter Six. Evgeniy Mikhailovich Bogachev -- Conclusion -- Bibliography.This thesis explores the cybercrime of malware through case study research. In doing so, the paper will apply rational choice theory, specifically Cornish and Clarkes (1986) rational choice perspectives, to malware architects Robert Tappan Morris and David Lee Smith, as well as alleged malware architect Evgeniy Mikhailovich Bogachev. As will be demonstrated, each of the three-case examples, spread over four decades,have contributed to the development of future malware through their architecture and design, providing a critical timeline of events and motivation.The primary aim of the research is to establish whether rational choice is an appropriate theory to apply to malware architects. As such, this thesis explores a variety of complex issues, with the intention of gaining insights into why malware architects commit their crimes. This thesis is intended to help fill a gap in criminological knowledge regarding malware and provide a pathway to future research into malware and malware architects.Mode of access: World wide web1 online resource (107 pages
Competing cosmologies in early Christianity: cosmology in the book of Revelation, Roman imperial ideology, and in the province of Asia
No full textTheoretical thesis.Bibliography: pages 390-427.1. Introduction -- 2. Methodology -- 3. The context and content of Revelation -- 4. Cosmology and its relationship to ideology and social identity -- 5. Ancient cosmologies -- 6. The cosmological dimension of Roman imperial ideology -- 7. The cosmology of the book of Revelation -- 8. The cosmology of Revelation: engaging with Rome, the province, and John's rivals -- 9. Conclusions: cosmology in the book of Revelation, Roman imperial ideology, and in the province of Asia.As Christianity emerged in the first century, individuals and communities that identified with the movement were faced with the need to formulate a Christian identity in the context of their sociopolitical situations and to determine the nature of their engagement with their societies. The rhetoric of the book of Revelation is properly interpreted in this setting with the crucial components of the sociopolitical situation including the Roman Empire and the poleis of the province of Asia. In the present thesis, it is argued that a significant aspect of Revelation's rhetoric is its cosmology, which functioned to legitimate a Christian identity which featured opposition to the power and influence of Rome and which required abstention from social practices that might identify a person with the local polis. The function of cosmology in the narrative of Revelation is analysed primarily in relation to the cosmological dimension of Roman imperial ideology but also in relation to the manifestation of these conceptions in the province of Asia. The thesis demonstrates that in Revelation, cosmic powers are reconfigured and redefined to deny Rome heavenly legitimation of its imperium, which is instead portrayed as a doomed diabolic stratagem intended to prevent the foundation of the true universal kingdom of God and Christ. This cosmological narrative contrasts with the approach of local elites in the province of Asia who established prestige for both themselves and their cities by affirming aspects of Roman cosmology. It may have also contrasted with a rival Christian cosmology which also accommodated aspects of Rome's cosmology to justify a greater degree of identification with the local polis and participation in its society. The thesis demonstrates that the study of cosmology provides valuable insights into the way early Christian communities established identities in the context of diverse and sometimes competing ideologies.1 online resource (427 pages : illustrations
Bacterial volatiles as potential new attractants for the Island Fly (Dirioxa pornia) (Tephritidae: Phytalmiinae)
No full textEmpirical thesis.Bibliography: pages 44-50.Chapter 1. Introduction -- Chapter 2. Experimental methods -- Chapter 3. Results & discussion -- Chapter 4. Results -- Chapter 5. Conclusions & future directions -- References -- Appendices.Many fruit fly species have a detrimental impact on food production. Lure and kill and mass trapping methods are becoming more important for crop protection, but currently, Island Fly (Dirioxa pornia) does not have a specific attractive lure for males and females. This study is initial research into olfactory responses to gut bacteria emissions.Fruit flies use olfactory cues for locating bacteria that assist in their development cycle. The ingestion of food together with naturally occurring bacteria allows a microbiome to form in their intestinal tract. This project investigated the gut microbiome of laboratory reared Island Flies, the chemical composition of the volatiles released from these microbes by GC-MS and the attractiveness of Island Flies to the volatile isolates using Y-tube olfactometry, electroantennography and wind tunnel experiments.All bioassay results of Island flies showed a rapid attraction towards the identified bacterial volatile isolates of Bacillus sp. and deterrence towards Citrobacter freundii. Other bacterial isolates of Bacillus subtilis, Klebsiella oxytoca and Providencia rettgeri showed low to moderate attractions respectively. Bacillus sp. uniquely had alkanes, some alcohols, aldehydes and nitrogen containing compounds while C. freundii had many sulphur-containing compounds and acids. Further studies on these compounds may assist in the development of a microbial-based lure.Mode of access: World wide web1 online resource (viii, 68 pages) illustrations (some colour