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Virtual trial to evaluate the robustness of cementless femoral stems to patient and surgical variation
Get PDF© 2018 Elsevier Ltd. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 12 month embargo from date of publication (November 2018) in accordance with the publisher’s archiving policyPrimary stability is essential for the success of cementless femoral stems. In this study, patient specific finite element (FE) models were used to assess changes in primary stability due to variability in patient anatomy, bone properties and stem alignment for two commonly used cementless femoral stems, Corail® and Summit® (DePuy Synthes, Warsaw, USA). Computed-tomography images of the femur were obtained for 8 males and 8 females. An automated algorithm was used to determine the stem position and size which minimized the endo-cortical space, and then span the plausible surgical envelope of implant positions constrained by the endo-cortical boundary. A total of 1952 models were generated and ran, each with a unique alignment scenario. Peak hip contact and muscle forces for stair climbing were scaled to the donor’s body weight and applied to the model. The primary stability was assessed by comparing the implant micromotion and peri-prosthetic strains to thresholds (150 μm and 7000 µε, respectively) above which fibrous tissue differentiation and bone damage are expected to prevail. Despite the wide range of implant positions included, FE prediction were mostly below the thresholds (medians: Corail®: 20–74 µm and 1150–2884 µε, Summit®: 25–111 µm and 860–3010 µε), but sensitivity of micromotion and interfacial strains varied across femora, with the majority being sensitive (p < 0.0029) to average bone mineral density, cranio-caudal angle, post-implantation anteversion angle and lateral offset of the femur. The results confirm the relationship between implant position and primary stability was highly dependent on the patient and the stem design used
Plio-Pleistocene diversification and biogeographic barriers in southern Australia reflected in the phylogeography of a widespread and common lizard species
Get PDF© 2018 Elsevier Inc. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 12 month embargo from date of publication (December 2018) in accordance with the publisher’s archiving policyPalaeoclimatic events and biogeographical processes since the mid-Tertiary have played an important role in shaping the evolution and distribution of Australian fauna. However, their impacts on fauna in southern and arid zone regions of Australia are not well understood. Here we investigate the phylogeography of an Australian scincid lizard, Tiliqua rugosa, across southern Australia using mitochondrial DNA (mtDNA) and 11 nuclear DNA markers (nuDNA), including nine anonymous nuclear loci. Phylogenetic analyses revealed three major mtDNA lineages within T. rugosa, geographically localised north and south of the Murray River in southern Australia, and west of the Nullarbor Plain. Molecular variance and population analyses of both mtDNA and nuDNA haplotypes revealed significant variation among the three populations, although potential introgression of nuDNA markers was also detected for the Northern and Southern population. Coalescent times for major mtDNA lineages coincide with an aridification phase, which commenced after the early Pliocene and increased in intensity during the Late Pliocene-Pleistocene. Species distribution modelling and a phylogeographic diffusion model suggest that the range of T. rugosa may have contracted during the Last Glacial Maximum and the locations of optimal habitat appear to coincide with the geographic origin of several distinct mtDNA lineages. Overall, our analyses suggest that Plio-Pleistocene climatic changes and biogeographic barriers associated with the Nullarbor Plain and Murray River have played a key role in shaping the present-day distribution of genetic diversity in T. rugosa and many additional ground-dwelling animals distributed across southern Australia
Modelling size constraints on carbonate platform formation in groundwater upwelling zones
Get PDFOpen Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.Carbonate depositional systems related to groundwater upwelling are ubiquitous around the world and form ecologically and culturally important features of many landscapes. Spring carbonate deposits record past climatic and hydrological conditions. The reconstruction of past processes using spring carbonate proxies requires fundamental understanding of the factors that control their geometry. In this work, we show that the spatial extent of spring carbonate platforms is amenable to quantitative prediction by simulating the early growth stage of their formation for the iconic mound springs in the central Australian outback. We exploit their well-defined, circular geometry to demonstrate the existence of two size-limiting regimes: one controlled by the spring flow rate and the other by the concentration of lattice ions. Deviations between modelled and observed size metrics are attributable to diminishing spring flow rates since formation, enabling assessment of the relative vulnerability of springs to further hydrological change
Vulnerability mapping of coastal aquifers to seawater intrusion: Review, development and application
Get PDF© 2018 Published by Elsevier Ltd. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 24 month embargo from date of publication (December 2018) in accordance with the publisher’s archiving policyIn this study, a review of the overlay/index methods served for delineation of vulnerable zones in coastal aquifers affected by SWI is provided. Then, a more realistic presentation of the vulnerability mapping of coastal aquifers to SWI through modified GALDIT index method by incorporating the influential factors on SWI is established. The modifications on GALDIT method including incorporating the seaward hydraulic gradient (i) instead of the height of groundwater level above sea level (L) (so-called GAiDIT), and considering hydraulic gradient (i) as an additional parameter to the GALDIT (so-called GALDIT-i). Three GALDIT, GAiDIT, and GALDIT-i methods were evaluated with data from three coastal confined and phreatic/confined aquifers located in the south of the Caspian Sea, northern Iran. While no highly vulnerable zone was recognized by GALDIT method across three studied aquifers, averagely 43.4% and 50.5% of aquifers area were defined as highly vulnerable zones by GAiDIT and GALDIT-i, respectively. Furthermore, the final vulnerability maps obtained by GALDIT-i and then GAiDIT indicates higher correlation by three groundwater quality indices specific to SWI including ( = 0.72 and 0.63) and ( = 0.69 and 0.62) and also the distribution of TDS in groundwater ( = 0.71 and 0.61) compared with GALDIT ( = 0.33, 0.42, and 0.36, respectively). The values of vulnerability index obtained by GALDIT-i and GAiDIT are more strongly correlated with the length of SWI into the aquifer () based on Strack's analytical approach than GALDIT ( = 0.52, 0.36, and 0.32, respectively). The results of sensitivity analysis indicated that the hydraulic gradient, height of groundwater level above sea level, aquifer type, and existing status of seawater intrusion has the greatest impact on the groundwater vulnerability across the studied aquifers by GALDIT-i and GAiDIT methods. Results also indicated that serving the influential parameters in GALDIT methods regarding the hydrological and anthropogenic characteristics across the aquifer provide a more realistic characterization of the SWI. This modification leads to an accurate aquifer vulnerability mapping to SWI in aquifers characterized by transient anthropogenic drivers (e.g. pumping) which can be served as a promising tool for decision-making to properly assess and manage risk
On the Dynamics of Canyon–Flow Interactions
Get PDF© 2018 by the author. Licensee MDPI, Basel, Switzerland. This article is an open access
article distributed under the terms and conditions of the Creative Commons Attribution
(CC BY) license (http://creativecommons.org/licenses/by/4.0/).This paper explores the dynamical origin and physical characteristics of flow disturbances induced by ocean currents in interaction with shelf-incised submarine canyons. To this end, a process-oriented hydrodynamic model is applied in a series of case studies. The focus of studies is the canyon-upwelling process in which seawater is moved from the upper continental slope onto the shelf within a shelf-break canyon. Results reveal that the generation of canyon upwelling, to zero-order approximation, is a barotropic and friction-independent quasi-geostrophic process. Hence, the principle of conservation of potential vorticity for such flows is sufficient to explain the fundamental physical properties of the canyon-upwelling process. For instance, this principle explains the direction-dependence of the canyon-upwelling process. This principle also explains the formation of stationary topographic Rossby waves downstream from the canyon that can lead to far-field effects. Density effects, being of secondary influence to the canyon-upwelling process, result in the intensification of canyon-upwelling flows via the formation of narrow near-bottom density fronts and associated baroclinic geostrophic frontal flows. Findings of this work reveal that the apparently complex canyon-upwelling process is much more basic than previously thought. View Full-Tex
Sustained improvement in vancomycin dosing and monitoring post-implementation of guidelines: Results of a three-year follow-up after a multifaceted intervention in an Australian teaching hospital
Get PDFCopyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Introduction
Despite vancomycin being in use for over half-a-century, it is still not dosed or monitored appropriately in many centers around the world. The objective of this study was to determine the effectiveness of a multifaceted intervention to implement a vancomycin dosing and monitoring guideline across multiple medical and surgical units over time.
Methods
This was an observational before-and-after interventional cohort study. The pre-intervention period was August to December 2010–2011 and the post-intervention period was September to November 2012–2014. The implementation strategy comprised: face-to-face education, online continuing medical education, dissemination of pocket guideline and email reminder. Outcome measures included: appropriate prescribing of loading and maintenance doses, therapeutic drug monitoring, time to attain target range and nephrotoxicity.
Results
Post-implementation prescribing of loading doses increased (10.4%–43.6%, P=<0.001), guideline adherent first maintenance dose (44%–68.4% P = 0.04), correct dose adjustment from (53.1%–72.2%, P = 0.009). Beneficial effects pre and post-implementation were observed for adherent timing of initial concentration (43.2%–51.9%, P = 0.01), concentrations in target range (32.6%–44.1%, P = 0.001), time to target range (median 6–4 days, P=<0.001), potentially nephrotoxic concentrations (30.7%–20.9%, P=<0.001) and nephrotoxicity (10.4%–6.8%, P=<0.001).
Conclusions
A multifaceted intervention to implement a vancomycin dosing and monitoring guideline significantly improved prescribing, monitoring, pharmacokinetic and safety outcomes for patients treated with vancomycin over an extended period. However, increased guideline adoption by clinicians is required to maximize and prolong the utility of this important agent
Do guidelines provide evidence-based guidance to health professionals on promoting developmentally appropriate chronic condition self-management in children? A systematic review
Get PDF© The Author(s) 2018Objectives
To determine whether evidence-based practice guidelines promote developmentally appropriate chronic condition self-management for children with asthma, type 1 diabetes mellitus, and cystic fibrosis.
Methods
Systematic review of clinical guidelines current as at 22 September 2017, including assessment of quality of each guideline using the iCAHE ‘Guideline Quality Checklist’, and mapping of the supporting evidence.
Results
Fifteen guidelines were identified: asthma (n=7) and type 1 diabetes mellitus (n=7), CF (n=1). Guideline quality was variable, and 11 different grading systems were used. In total, there were 28 recommendations promoting age/developmental considerations. Recommendations focused on: collaboration (n=15), chronic condition self-management education (n= 17), clinicians’ skills (n= 4); personalized action plans (n=3), problem-solving (n=2); and the assessment of children’s chronic condition self-management needs (n=3). Developmental transitions are highlighted as important time points in some guidelines: preschool (n=2), and adolescence (n=3). All guidelines encouraged triadic partnerships between children, adult caregivers and clinicians. Evidence supporting the developmental aspects of the guidelines’ recommendations was poor; only 14 out of 57 journals listed as evidence were concordant.
Discussion
Current guidelines articulate that developmentally appropriate chronic condition self-management is important; however, more work needs to be done to translate the concept into practical clinical tools.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Nicole Saxby was supported to complete this research by a Nursing and Allied Health Scholarship and Support Scheme: NAHSSS Postgraduate Scholarship
The Relative Validity of the Menzies Remote Short-Item Dietary Assessment Tool (MRSDAT) in Aboriginal Australian Children Aged 6–36 Months
Get PDF© 2018 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).The Menzies Remote Short-item Dietary Assessment Tool (MRSDAT) can be used to derive a dietary index score, which measures the degree of compliance with the Australian Dietary Guidelines. This study aimed to determine the relative validity of a dietary index score for children aged 6–24 months, living in a Remote Aboriginal Community (RAC), derived using MRSDAT. This validation study compared dietary index scores derived using MRSDAT with those derived from the average of three 24-h recalls. Participants were aged 6–36 months at the first dietary assessment and were living in a RAC. The level of agreement between the two methods was explored using Lin’s concordance correlation coefficient (CCC), Bland-Altman plots, weighted Cohen’s kappa, and Fischer’s exact and paired t-tests. Forty participants were recruited. The CCC was poor between methods (R = 0.35, 95% CI 0.06, 0.58), with MRSDAT estimating higher dietary intake scores for all food groups except fruit, and higher dietary quality scores by an average of 4.78 points/100. Community-based Aboriginal researchers were central to this validation study. MRSDAT was within the performance range of other short-item dietary assessment tools developed for young children, and shows promise for use with very young children in RACs. View Full-Tex
A mixed methods systematic review of studies examining the relationship between housing and health for people from refugee and asylum seeking backgrounds
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available under the CC-BY-NC-ND 4.0 license:
http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 36 month embargo from date of publication (July 2018) in accordance with the publisher’s archiving policyHousing is an important social determinant of health and a key element of refugee integration into countries of resettlement. However, the way in which housing may affect mental and physical health for refugees and asylum seekers has not been systematically examined. This systematic review aimed to explore the effects of housing on health and wellbeing for this population, in order to identify key pathways for public health interventions. The review was undertaken following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Social Care Institute for Excellence (SCIE) guidelines. We identified publications through a search of Medline, PsychInfo, Scopus, Web of Science, Embase, CINAHL, Cohrane Library, Google, ProQuest, OpenGrey, MedNar and WHOLIS. Eligibility criteria included: publication in English between 1997 and 2017, with findings pertaining to the relationship between housing and health for refugees and/or asylum seekers. Out of 2371 items, 25 papers were included with a further five identified through reference lists. Eleven of the papers explored housing and health for those refugees and asylum seekers living within refugee camps, with 19 focusing on countries of resettlement. All studies identified housing issues for refugees and asylum seekers, with physical housing conditions particularly poor in refugee camps, and issues of affordability, suitability, insecure tenure and mobility as well as difficulties securing housing also highlighted in countries of resettlement. Consistent relationships were found between physical aspects of housing and physical and mental health, with other aspects of housing such as safety and overcrowding linked to mental health. There were a number of methodological issues with most of the studies, making it difficult to specify precise pathways. However, improvements to housing quality particularly in refugee camps, and targeted housing interventions more generally for refugees and asylum seekers would likely have an important public health benefit.This review was not directly funded, but was conducted by the authors who were funded through an Australian Research Council grant and fellowship (LP130100782, FT120100150)
Development of a short‐item diet quality questionnaire for Indigenous mothers and their young children: The Menzies remote short‐item dietary assessment tool
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Copyright © 2018 National Rural Health Alliance Ltd.The importance of a healthy diet in facilitating optimal childhood development and preventing chronic disease cannot be overstated. Despite this, unhealthy food patterns frequently occur as early as 9 months of age and continue through childhood. Australian Bureau of Statistics data indicate Indigenous Australian children to have particularly concerning dietary patterns, with children aged 2–3 years three times more likely to consume carbonated sugary drinks than their non‐Indigenous counterparts (18% versus 5.8%, respectively).1 Early intervention to prevent or improve obesity‐related behaviours can have a positive impact. The ability to improve dietary outcomes depends primarily on an accurate assessment of dietary intake. Data reliability and compliance issues common in dietary assessment are exacerbated when working with Indigenous Australians living remotely due to existing tools using inappropriate language, being resource‐intensive and not incorporating culturally diverse foods and serving methods. The aim of this research was to develop a short‐item questionnaire to assess the dietary quality of mothers and their young children (2–4 years) in the remote Indigenous community (RIC) setting for the Pregnancy and Adverse Neonatal Diabetes Outcomes in Remote Australia (PANDORA) longitudinal birth cohort study.2 PANDORA participants are Northern Territory women (both Indigenous and non‐Indigenous) with and without diabetes during pregnancy and their babies