Lessons learned from measuring safety culture: An Australian case study

Background: adverse events in maternity care are relatively common but often avoidable. International patient safety strategies advocate measuring safety culture as a strategy to improve patient safety. Evidence suggests it is necessary to fully understand the safety culture of an organisation to make improvements to patient safety. Aim: this paper reports a case study examining the safety culture in one maternity service in Australia and considers the benefits of using surveys and interviews to understand safety culture as an approach to identify possible strategies to improve patient safety in this setting. Setting: the study took place in one maternity service in two public hospitals in NSW, Australia. Concurrently, both hospitals were undergoing an organisational restructure which was part of a major health reform agenda. The priorities of the reform included improving the quality of care and patient safety; and, creating a more efficient health system by reducing administration inefficiencies and duplication. Design: a descriptive case study using three approaches: • Safety Attitudes Questionnaire and Safety Climate Scale surveys administered to maternity health professionals (59/210, 28% response rate) measured six safety culture domains: Safety climate, Teamwork climate, Job satisfaction, Perceptions of management, Stress recognition and Working conditions. • Semi-structured interviews (15) with key maternity, clinical governance and policy stakeholders augmented the survey data and explored the complex issues associated with safety culture. • A policy audit and chronological mapping of the key policies influencing safety culture identified through the surveys and interviews within the maternity service. Findings: the safety culture was identified to warrant improvement across all six safety culture domains. There was reduced infrastructure and capacity to support incident management activities required to improve safety, which was influenced by instability from the organisational restructure. There was a perceived lack of leadership at all levels to drive safety and quality and improving the safety culture was neither a key priority nor was it valued by the organisation. Conclusion: the safety culture was complex as was undertaking this study. We were unable to achieve a desired 60% response rate highlighting the limitations of using safety culture surveys in isolation as a strategy to improve safety culture. Qualitative interviews provided greater insight into the factors influencing the safety culture. The findings of this study provide evidence of the benefits of including qualitative methods with quantitative surveys when examining safety culture. Undertaking research in this way requires local engagement, commitment and capacity from the study site. The absence of these factors is likely to limit the practicality of this approach in the clinical setting. Significance: the use of safety culture surveys as the only method of assessing safety culture is of limited value in identifying strategies to potentially improve the safety culture. © 2010 Elsevier Ltd

A volatility decomposition control variate technique for Monte Carlo simulations of Heath Jarrow Morton models

The aim of this work is to develop a simulation approach to the yield curve evolution in the Heath, Jarrow and Morton [Econometrica 60 (1) (1992) 77] framework. The stochastic quantities considered as affecting the forward rate volatility function are the spot rate and the forward rate. A decomposition of the volatility function into a Hull and White [Rev. Financial Stud. 3 (1990) 573] volatility and a remainder allows us to develop an efficient Control Variate Method that makes use of the closed form solution of the Hull and White call option. This technique considerably speeds up the simulation algorithm to approximate call option values with Monte Carlo simulation. © 2003 Elsevier B.V. All rights reserved

Stock market, interest rate and output: a model and estimation for US time series data

Stock market, interest rate and output: a model and estimation for US time series dat

On numerical solution of Fredholm and Hammerstein integral equations via Nystr\"{o}m method and Gaussian quadrature rules for splines

Nystr\"{o}m method is a standard numerical technique to solve Fredholm integral equations of the second kind where the integration of the kernel is approximated using a quadrature formula. Traditionally, the quadrature rule used is the classical polynomial Gauss quadrature. Motivated by the observation that a given function can be better approximated by a spline function of a lower degree than a single polynomial piece of a higher degree, in this work, we investigate the use of Gaussian rules for splines in the Nystr\"{o}m method. We show that, for continuous kernels, the approximate solution of linear Fredholm integral equations computed using spline Gaussian quadrature rules converges to the exact solution for $m \rightarrow \infty$, $m$ being the number of quadrature points. Our numerical results also show that, when fixing the same number of quadrature points, the approximation is more accurate using spline Gaussian rules than using the classical polynomial Gauss rules. We also investigate the non-linear case, considering Hammerstein integral equations, and present some numerical tests.RYC-2017-2264

Structure and morphology of an active conjugate relay zone, Messina Strait, southern Italy

Messina Strait is a narrow fault-bounded marine basin that separates the Calabrian peninsula from Sicily in southern Italy. It sits in a seismically active region where normal fault scarps and raised Quaternary marine terraces record ongoing extension driven by southeastward rollback of the Calabrian subduction zone. A review of published studies and new data shows that normal faults in the Messina Strait region define a conjugate relay zone where displacement is transferred along strike from NW-dipping normal faults in the northeast (southern Calabria) to the SE-dipping Messina-Taormina normal fault in the southwest (offshore eastern Sicily). The narrow marine strait is a graben undergoing active subsidence within the relay zone, where pronounced curvature of normal faults results from large strain gradients and clockwise rotations related to fault interactions. Based on regional fault geometries and published age constraints, we infer that normal faults in southern Calabria migrated northwest while normal faults in NE Sicily migrated southeast during the past ca. 2–2.5 Myr. This pattern has resulted in tectonic narrowing of the strait through time by inward migration of facing normal faults and rapid mantle-driven uplift

Structural investigation of nucleophosmin interaction with the tumor suppressor Fbw7γ

Nucleophosmin (NPM1) is a multifunctional nucleolar protein implicated in ribogenesis, centrosome duplication, cell cycle control, regulation of DNA repair and apoptotic response to stress stimuli. The majority of these functions are played through the interactions with a variety of protein partners. NPM1 is frequently overexpressed in solid tumors of different histological origin. Furthermore NPM1 is the most frequently mutated protein in acute myeloid leukemia (AML) patients. Mutations map to the C-terminal domain and lead to the aberrant and stable localization of the protein in the cytoplasm of leukemic blasts. Among NPM1 protein partners, a pivotal role is played by the tumor suppressor Fbw7γ, an E3-ubiquitin ligase that degrades oncoproteins like c-MYC, cyclin E, Notch and c-jun. In AML with NPM1 mutations, Fbw7γ is degraded following its abnormal cytosolic delocalization by mutated NPM1. This mechanism also applies to other tumor suppressors and it has been suggested that it may play a key role in leukemogenesis. Here we analyse the interaction between NPM1 and Fbw7γ, by identifying the protein surfaces implicated in recognition and key aminoacids involved. Based on the results of computational methods, we propose a structural model for the interaction, which is substantiated by experimental findings on several site-directed mutants. We also extend the analysis to two other NPM1 partners (HIV Tat and CENP-W) and conclude that NPM1 uses the same molecular surface as a platform for recognizing different protein partners. We suggest that this region of NPM1 may be targeted for cancer treatment

Quantum phase slips in superconducting Nb nanowire networks deposited on self-assembled Si templates

Robust porous silicon substrates were employed for generating interconnected networks of superconducting ultrathin Nb nanowires. Scanning electron microscopy analysis was performed to investigate the morphology of the samples, which constitute of polycrystalline single wires with grain size of about 10 nm. The samples exhibit nonzero resistance over a broad temperature range below the critical temperature, fingerprint of phase slippage processes. The transport data are satisfactory reproduced by models describing both thermal and quantum fluctuations of the superconducting order parameter in thin homogeneous superconducting wires.Comment: accepted for publication on Applied Physics Letter

Coarse-grained deltas approaching shallow-water canyon heads: A case study from the Lower Pleistocene Messina Strait, Southern Italy

The tide-dominated Messina Strait (southern Italy) is a 3 km wide marine passageway, whose block-faulted borders form steep subaqueous zones incised by canyons and gullies. These erosional features retreat towards the shorelines and are often in direct connection with subaerial valley-bounded river deltas. High-energy density-flows generated by river floods periodically enter the canyon heads, attaining supercritical-flow regime and accreting large, upslope-migrating bedforms. Although these bedforms have been documented in recent studies, little attention has been paid to the definition of the type of delta entering canyon heads, the internal features of river-influenced deposits accumulated in the nearshore zone, and their interplay with tidal currents flowing axially to the strait. This study focuses on a Lower Pleistocene coarse-grained succession exposed along the north-eastern margin of the modern Messina Strait, investigated using conventional facies analysis and sedimentological logging, integrated with photogrammetric techniques and interpretation of drone-acquired imagery. Facies confinement between basement blocks suggests a subaqueous delta complex shed from the tectonically controlled margin of the ancient strait and entering shallowly submerged canyon heads. Basal breccias, conglomerates and pebbly sandstones exhibiting channel-form discontinuities and upslope dipping backsets are interpreted as cyclic-step and antidune deposits. Units composed of these facies are comprised between master erosional surfaces and tidal ravinement surfaces. The tidal ravinements suggest that canyon infill occurred during a major phase of sea-level rise, punctuated by minor falls and stillstands. These surfaces are overlain by mixed bioclastic–siliciclastic, arenitic, trough and planar cross-strata, representing dunes migrating roughly parallel to the palaeo-coastline and originated by tidal currents amplified by the narrowing of the ancient Messina Strait. Tidal-influenced sedimentation dominated over the fluvial-influenced processes during the late transgression, overfilling the canyon relief. The exceptionally good exposure of depositional architectures and facies characteristics is key to outline the general features of a specific type of delta system, fed by valley-bounded rivers and entering canyon heads in the nearshore of tectonically-controlled, tide-influenced steep strait margins. The pre-existing subaqueous incised topography forced the delta front to be split into lobe branches during the canyon infilling, hampering clinoform architectures and preserving large supercritical-flow sedimentary structures. This study suggests these as possible criteria for the recognition of similar systems in outcrop or subsurface

Sedimentology and facies analysis of ancient sand ridges: Jurassic Rogn Formation, Trøndelag Platform, offshore Norway

Sand ridges represent a common type of sedimentary bedform of modern shelves seldom used as analogues to interpret isolated marine sandbodies recognised in the subsurface. Lack of extended literature on outcrop and subsurface examples limits the possibility for their recognition and seems one of the reason behind this underrepresentation. The Draugen discovery made in the early 80's represents an unicum in the Trøndelag Platform, offshore Norway. After more than 30 years the Froan Basin and Frøya High area are still underexplored and the Late Jurassic Rogn Fm play not well understood. Predicting reservoir distribution, and its internal architecture and properties requires the understanding of factors controlling sedimentation (e.g. palaeocirculation, depositional processes). North-south elongated sandbodies pertaining to the Rogn Formation are recognised in the Froan Basin and Frøya High encased within thick shaly deposits. Sandbodies develop above a ravinement or flooding surface (i.e. Callovian Unconformity) of regional extent where local depressions occur with a non-erosional concave-up top. Depressions representing the depositional loci for the accumulation of sand and development of the ridge. The presence of eastward and westward dipping reflections within the sandbodies allows identifying their large-scale architectures. Sediments form coarsening-upward vertical units characterised by a shaly base evolving upwards to medium- and coarse-grained sand forming tabular and trough cross strata. Locally, a fining upward trend characterised by plane-parallel stratification and coarse-grained massive layers is recognised. Sediments results well organised and sorted, which positively affects final porosity and permeability with values up to 30% and 6 Darcy, respectively - typical values for many sand ridges. Accordingly, sand ridges encased within thick shaly deposits can form stratigraphic traps with the potential for large hydrocarbon accumulations. The aim of the present study is to help the understanding of distribution, and internal architectures and properties of the Rogn Fm in the Trøndelag Platform