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The role of information systems and knowledge codification for service provision strategies
No full textPurpose: While service scholars see modularisation as balancing the efficiency of standardisation with the value added through customisation the relationships between these concepts are under-theorised. In addition, although information and communication technologies can facilitate all three service strategies, the degree to which they codify service knowledge is not explicitly considered in the extant literature. The purpose of this paper is to develop and validate a model that examines service strategy trajectories by specifically considering the ICTs used and the degree of knowledge codification employed. Design/methodology/approach: This study draws on three qualitative case studies of service departments of firms involved in cardiovascular applications, orthopaedic, spinal and neuroscience product development and information technology support. Data collection involved semi-structured interviews, document analysis and non-participant observation. Findings: Findings show that ICTs were increasingly used to codify both standardised and customised services, though in different ways. For standardised services ICTs codified the service process, making them even more rigid. Due to the dynamic nature of customised services, drawing on experts\u27 tacit knowledge, ICTs codified the possessors of knowledge rather than the service process they undertook. This study also identified a duality between the tacit development of customised services and modular service codification. Research limitations/implications: The model is validated using case studies from three companies in the medical and information technology sectors limiting its generalisability. Practical implications: The importance of considering the degree of tacitness or explicitness of service knowledge is important for service codification. The paper provides managers with empirical examples of how ICTs are used to support all three strategies, allows them to identify their current position and indicates possible future trajectories. Originality/value: The papers main contribution is the development of a model that integrates the literature on service strategies with knowledge management strategies to classify service standardisation, customisation and modularisation in terms of both service orientation and degree of ICT codification.ACCEPTEDpeer-reviewe
Flexible hinges in orthotropic cylindrical shells facilitated by nonlinear elastic deformations
No full textFlexible hinges enable the design of folding structures without using mechanisms by making use of intrinsic structural characteristics in the action of folding. This technology introduces potential benefits including weight reduction, omission of lubrication and potentially better system reliability. To achieve such technology, we exploit a well‐known structural instability characteristic of thin‐walled structures under bending: the Brazier effect. Composite materials play a key role in this problem since they enable the critical load for folding to be tuned. Moreover, the minimisation of the Brazier moment is material dependent, offering extra degrees of freedom for morphing purposes. The present work considers the minimisation of the Brazier moment providing insights on its material dependency. For this purpose, an analytical solution for cylindrical shells made of uni
directional laminates and an empirical expression useful for design purposes, comprising 4‐ply symmetric laminates, are presented with validation accomplished
using finite element analysis
Quantum stochastic socycles and completely bounded semigroups on operator spaces II
No full textQuantum stochastic cocycles provide a basic model for time-homogeneous Markovian evolutions in a quantum setting, and a direct counterpart in continuous time to quantum random walks, in both the Schrödinger and Heisenberg pictures. This paper is a sequel to one in which correspondences were established between classes of quantum stochastic cocycle on an operator space or C∗-algebra, and classes of Schur-action ‘global’ semigroup on associated matrix spaces over the operator space. In this paper we investigate the stochastic generation of cocycles via the generation of their corresponding global semigroups, with the primary purpose of strengthening the scope of applicability of semigroup theory to the analysis and construction of quantum stochastic cocycles. An explicit description is given of the affine relationship between the stochastic generator of a completely bounded cocycle and the generator of any one of its associated global semigroups. Using this, the structure of the stochastic generator of a completely positive quasicontractive quantum stochastic cocycle on a C∗-algebra whose expectation semigroup is norm continuous is derived, giving a comprehensive stochastic generalisation of the Christensen–Evans extension of the GKS&L theorem of Gorini, Kossakowski and Sudarshan, and Lindblad. The transformation also provides a new existence theorem for cocycles with unbounded structure map as stochastic generator. The latter is applied to a model of interacting particles known as the quantum exclusion Markov process, in particular on integer lattices in dimensions one and two
Development of an Objective Assessment of the Cognitive, Posturographic, and Electrophysiological Phenotype of the Fragile X Premutation, and analysis of their contribution to Postural Instability.
No full textThe Fragile X Premutation is a complex genetic anomaly which affects one in 260 females and 400 males and results in a broad range of symptoms and distinct conditions. The premutation phenotype involves cognitive and motor impairment as well as increased risk of developing the neurodegenerative movement disorder Fragile X Associated Tremor Ataxia Syndrome (FXTAS). FXTAS is characterised by clinically significant cognitive and motor impairments as well as balance deficits, subsequently leading to falls, injuries, and even hospitalisation. However, due to the relatively recent discovery of FXTAS and the premutation phenotype, the pathophysiology and progression of motor symptoms towards the development of FXTAS are not clear and current evaluations of motor and neurological health involve subjective rating scale based assessments or time-consuming neuroimaging techniques, therefore there is an urgent clinical need for objective, time-efficient clinical assessments of patient health to allow for early interventions.
In this thesis, a protocol, with foundations based on posturography based measures of stability, was developed to objectively assess balance and postural control in younger Premutation Carriers without FXTAS. Posturographic measures were recorded during altered cognitive and sensory conditions to emulate situations experienced during daily life. Both clinically interpretable measures of postural sway were assessed as well as more complex entropy-based measures of postural control. Furthermore, electrophysiological imaging methods were employed to investigate potential alteration in neural activity which may underlie the changes in motor functioning, providing new insight into the Fragile X Premutation related pathomechanisms of instability. The central aim of this thesis was to employ a multimodal approach to objectively assess and characterise premutation related cognitive and motor symptoms in younger, seemingly asymptomatic Fragile X Premutation Carriers.
The main findings of the studies presented in this thesis suggest that the protocol developed is effective in probing deficits in cognitive and sensory functioning experienced by carriers to elicit decreased stability in younger female Premutation Carriers, and that classical sway parameters, alongside entropy-based measures of sway, are effective in detecting disparities in postural control of Premutation Carriers and unaffected Control subjects. Furthermore, the relationship between activation of specific electrophysiological frequency bands and postural performance, which has been established in unaffected control subjects, was lacking in Premutation Carriers, suggesting altered neural activation connectivity in carriers may contribute to aberrant postural control. It was shown that a combination of cognitive, posturographic and electrophysiological based methods provide an objective and information-rich assessment of motor functioning and neurophysiology of Fragile X Premutation Carriers. This highlights the efficacy and utility of a multimodal approach to assessments in clinical practice.
In conclusion, the original contribution to knowledge of this thesis lies in the development of a simple but comprehensive, easily administered, protocol for the objective assessment of stability and postural control and neurological health of young, asymptomatic Fragile X Premutation Carriers. The main findings of this thesis, therefore, can provide significant value for future research into the effects of the Fragile X Premutation. The cognitive, posturographic and electrophysiological based methods described in this thesis may yield information which can then be used to instigate conversations with patients surrounding health-related behaviours, personalised strategies for behavioural changes and preclusive measures to potentially delay onset or progression of symptoms, subsequently improving quality of life
Cardiovascular reactivity to acute stress: attachment styles and invisible stranger support
No full textWhile the benefits of social support for physiological health are well established, the underlying pathways by
which support can influence cardiovascular reactivity (CVR) are still being elucidated. In the present study, we
adapted an attachment framework to further explore the support-CVR link. Specifically, we experimentally tested
the effect of attachment and social support on CVR by manipulating the provision of invisible support from a
stranger, across individuals with secure, anxious and avoidant attachment styles. Employing a 3 × 2 design, a
sample of young adults (N = 138) from across each of the three attachment styles were randomly assigned to
either an invisible support (from a stranger), or no support, condition. All participants were subject to an acute
standardised stress testing protocol where cardiovascular indices were monitored throughout. Results from a
factorial ANOVA showed no significant interaction between support and attachment on any cardiovascular
reactivity parameter (SBP, DBP, HR) or any main effect of attachment or support. These findings suggest that, in
this case, social support was not effective in buffering the effects of stress across various attachment styles. The
benefits of incorporating a developmental perspective to the study of social support and health are discussed
Use of a sensitive multi-sugar test for measuring segmental intestinal permeability in critically ill mechanically ventilated adults: a pilot study
No full textThe full text of this article will not be available in ULIR until the embargo expires on the 24/03/2022Background
Increased intestinal permeability (IP) is associated with sepsis in the Intensive Care Unit (ICU). This study aimed to pilot a sensitive multi‐sugar test to measure IP in critically ill patients in the non‐fasted state.
Methods
Critically ill mechanically ventilated adults were recruited from two ICUs in Australia. Measurements were completed within three days of admission using a multi‐sugar test measuring gastroduodenal (sucrose recovery), small bowel (lactulose‐rhamnose [L‐R] and lactulose‐mannitol [L‐M] ratios) and whole gut permeability (sucralose‐erythritol [S‐E] ratio) in 24‐hour urine samples. Urinary sugar concentrations were compared at baseline and post‐sugar ingestion, and IP sugar recoveries and ratios were explored in relation to known confounders including renal function.
Results
Twenty‐one critically ill patients (12 males, median 57 years) participated. Group median concentrations of all sugars were higher following sugar administration; however, sucrose and mannitol increases were not statistically significant. Within individual patients, sucrose and mannitol concentrations were higher in baseline than post‐sugar ingestion in nine (43%) and four (19%) patients, respectively. Patients with impaired (n = 9) versus normal (n = 12) renal function had a higher L‐R ratio (median 0.130 versus 0.047,p = 0.003), a lower rhamnose recovery (median 15 versus 24%,p = 0.007) and no difference in lactulose recovery (median 2.5 versus 2.4%,p = 0.508).
Conclusion
Small bowel and whole gut permeability measurements are possible to complete in the non‐fasted state, while gastroduodenal permeability could not be measured reliably. For small bowel IP measurements, the L‐R ratio is preferred over the L‐M ratio. Alterations in renal function may reduce the reliability of the multi‐sugar IP test, warranting further exploration
Electrical, Mechanical & Morphological Characterisation of Nanosheet Networks
No full textNetworks of two-dimensional nanosheets have demonstrated significant promise across a host of applications that span the breadth of materials science. While this has driven research into nanosheet-based devices at a remarkable pace, a prevailing observation has been that the superlative physical properties of nanosheets do not naturally translate to their networks. To begin to address this dichotomy and realise their full potential, the electrical, mechanical and morphological properties of nanosheet networks are investigated in this work.
Composites of 2D nanosheets mixed with 1D single-walled carbon nanotubes (SWNTs) represent an exciting class of materials for electrochemical applications. Active material is supplied by the nanosheets while SWNTs provide mechanical reinforcement and enhanced electrical conductivity. Although charge transport in these systems has been studied, their mechanical properties have not yet been quantitatively examined. Here, both the mechanical and morphological character of SWNT / MoS2 1D:2D nanocomposites are investigated as a function of SWNT volume fraction, phi. Microscopic analysis reveals the reinforcing SWNT network to evolve from a loosely connected structure for phi 1 vol %. This transition has a considerable effect on the composite mechanical properties. Below 1 vol %, the composite modulus and failure-strain exhibit short-fibre composite behaviour. However, above 1 vol % both increase with phi in a manner consistent with fibrous networks. The composite tensile strength similarly evolves from a regime limited by the matrix-fibre interface at low-phi, to one limited by the strength of the nanotube ropes for phi > 1 vol %. Crucially, while the composite tensile toughness is constant at low-phi, it increases rapidly for phi > 1 vol % consistent with percolation theory. Quantitative models are presented to describe this mechanical evolution, which renders the composites robust at additive levels as low as 5 vol % SWNTs.
Owing to the diverse electronic properties of their constituent nanosheets, 2D networks are well-placed to feature prominently in the growing field of printed electronics. While it is known that electrical performance in printed 2D networks is impeded by inter-nanosheet junctions, work to characterise this effect has been limited. To address this, the electrical conductivity of printed nanosheet networks is investigated as a function of constituent nanosheet length, lNS. A family of size-selected WSe2, graphene and silver 2D inks, each spanning an order of magnitude in lNS, are synthesised and printed. The in-plane conductivity of spray-coated WSe2 networks is observed to decrease by an order of magnitude as lNS is reduced from 462 nm to 62 nm. Significantly, the conductivity in both graphene and silver nanoplatelet networks exhibits the opposite response, scaling with 1/lNS. A model to describe this length-dependent conductivity scaling in networks of solution-processed nanosheets is developed.
To conclude, focused ion beam and scanning electron microscope nanotomography (FIB:SEM NT) is presented as a novel technique to assess the morphology of nanostructured systems. This is demonstrated through a length-dependent investigation of printed graphene networks for lNS = 947, 630 and 215 nm. The network porosity is observed to steadily decrease from 49 % to 40 % as the constituent nanosheet length is reduced from 947 nm to 215 nm. Interestingly, the pore volume in each network is found to be highly contiguous with > 99 % of the total pore volume contained in a single open pore. A reduction in nanosheet size is seen to increase the specific surface area of the printed networks from 14 m2/g to 23 m2/g as lNS is decreased from 947 to 215 nm. Notably, both pore size and shape are found to be a function of nanosheet length. Finally, the alignment of each printed network is evaluated using Fourier transforms, where networks comprising larger nanosheets demonstrate enhanced alignment
Investigation of type I interferon responses in ANCA‑associated vasculitis
No full textType I interferon (IFN) dysregulation is a major contributory factor in the development of several autoimmune diseases, termed type I interferonopathies, and is thought to be the pathogenic link with chronic infammation in these conditions. Anti-neutrophil cytoplasmic antibody (ANCA)-Associated Vasculitis (AAV) is an autoimmune disease characterised by necrotising infammation of small blood vessels. The underlying biology of AAV is not well understood, however several studies have noted abnormalities in type I IFN responses. We hypothesised that type I IFN responses are systemically dysregulated in AAV, consistent with features of a type I interferonopathy. To investigate this, we measured the expression of seven interferon regulated genes (IRGs) (ISG15, SIGLEC1, STAT1,
RSAD2, IFI27, IFI44L and IFIT1) in peripheral blood samples, as well as three type I IFN regulated proteins (CXCL10, MCP-1 and CCL19) in serum samples from AAV patients, healthy controls and disease controls. We found no difference in type I IFN regulated gene or protein expression between AAV patients and healthy controls. Furthermore, IRG and IFN regulated protein expression did not correlate with clinical measurements of disease activity in AAV patients. Thus, we conclude that systemic type I IFN responses are not key drivers of AAV pathogenesis and AAV should not be considered a type I interferonopathy
LIBER Digital humanities and digital cultural heritage working group: a case study of international collaboration and network building
No full textHow can European library staff working in digital humanities connect with peers in the library sector, determine where to find relevant information about digital scholarship, provide their collections as data and to be an equal partner in digital humanities research? The LIBER Digital Humanities Working Group was created as a participatory knowledge network in 2017 to address these questions. Through a series of workshops, knowledge sharing activities, and a Europe-wide survey and resulting report, the Working Group engaged with the international LIBER DH community. Useful reflections are provided on
organising an open, voluntary DH community and planning for inclusive activities that benefit digital scholarship in European research libraries