The use of intravenous iron in pregnancy: for whom and when? A survey of Australian and New Zealand obstetricians

Background: Iron deficiency anaemia in pregnancy (IDAP) affects 11–18% of Australian pregnancies and is associated with adverse perinatal outcomes. National prescribing data suggests the use of intravenous iron in pregnancy is increasingly common. This study aimed to: 1) Establish the current patterns of intravenous iron use by Fellows of the Royal Australian and New Zealand College of Obstetricians (FRANZCOG) when treating iron deficiency and IDAP including immediately postpartum and; 2) Assess FRANZCOG opinions regarding potential trial of intravenous iron for first-line treatment of IDAP. Methods: An online survey of RANZCOG Fellows practicing obstetrics was distributed in September 2018. Results were analysed descriptively and responses compared by clinician demographics using Chi-squared testing. Results: Of 484 respondents (21% of FRANZCOG), 457 were currently practicing obstetrics. Most prescribed intravenous iron in pregnancy (96%) and/or postpartum (85%). Most intravenous iron was prescribed for IDAP (98%) rather than iron deficiency without anaemia (53%), and for IDAP most commonly second-line to failed oral iron supplementation and first-line in special circumstances (59%). Intravenous iron prescribing was associated with shorter time since FRANZCOG completion (p = 0.01), public hospital practice (p = 0.008) and higher hospital birth numbers (p = 0.01). Most respondents (90%) would consider a randomised controlled trial of first-line intravenous iron for IDAP, although views on appropriate thresholds differed. Conclusions: Almost all respondents prescribed intravenous iron for IDAP, and while mostly used for second-line treatment over half sometimes used it first-line. With accelerating intravenous iron use, further research is required into its optimal use in pregnancy, recognizing important clinical outcomes and cost effectiveness.Sarah Smith-Wade, Giselle Kidson-Gerber, Antonia Shand, Luke Grzeskowiak and Amanda Henr

Associations between stratospheric variability and tropospheric blocking

There is widely believed to be a link between stratospheric flow variability and stationary, persistent “blocking” weather systems, but the precise nature of this link has proved elusive. Using data from the ERA-40 Reanalysis and an atmospheric general circulation model (GCM) with a well-resolved stratosphere (HadGAM), it is shown that there are in fact several different highly significant associations, with blocking in different regions being related to different patterns of stratospheric variability. This is true in both hemispheres and in both data sets. The associations in HadGAM are shown to be very similar to those in ERA-40, although the model has a tendency to underestimate both European blocking and the wave number 2 stratospheric variability to which this is related. Although the focus is on stratospheric variability in general, several of the blocking links are seen to occur in association with the major stratospheric sudden warmings. In general, the direction of influence appears to be upward, as blocking anomalies are shown to modify the planetary stationary waves, leading to an upward propagation of wave activity into the stratosphere. However, significant correlations are also apparent with the zonal mean flow in the stratosphere leading the occurrence of blocking at high latitudes. Finally, the underestimation of blocking is an enduring problem in GCMs, and an example has recently been given in which improving the resolution of the stratosphere improved the representation of blocking. Here, however, another example is given, in which increasing the stratospheric resolution unfortunately does not lead to an improvement in blocking

Isothermal Elastohydrodynamic Lubrication Analysis of Heavily Loaded Hypoid Gear Pairs

A numerical model able to predict the pressure distribution and the film thickness in heavily loaded elliptical EHL contacts is developed and presented in this study. The operating conditions, such as the contact load and the velocities of the mating surfaces, are representative of the corresponding conditions present in automotive differential hypoid gear pair units. The EHL solver presented is able to predict the minimum and central film thickness of the lubricating oil as well as the pressure distribution assuming isothermal and Newtonian conditions. Results are presented for a full quasi-static meshing cycle. A comparison between the numerically calculated values of the central and the minimum film thickness is performed against the corresponding values produced using the Chittenden-Dowson formula. A very good agreement is observed between the values of the central film thickness. However, it is shown that the minimum film thickness values using the Chittenden-Dowson formula can deviate up to 40% compared with the corresponding values which are calculated numerically

Film Thickness Investigation in Heavily Loaded Hypoid Gear Pair Elastohydrodynamic Conjunctions

Introduction: Hypoid gear pairs are some of the most highly loaded components of the differential unit in modern automobiles. Prediction of wear rate and generated friction require determination of lubricant film thickness. However, only very few investigations have addressed the issue of thin elastohydrodynamic films in hypoid gear pairs. The main reason for dearth of analysis in this regard has been the need for accurate determination of transient contact geometry and kinematics of interacting surfaces throughout a typical meshing cycle. Furthermore, combined gear dynamics and lubrication analysis of any pairs of simultaneous meshing teeth pairs is required. Simon [1] was among the first to deal with these issues. He used Tooth Contact Analysis (TCA) in order to calculate the instantaneous contact geometry and load for any teeth pair during their meshing cycle. However, in his study, the load carried by the hypoid pair was quite low, making the application of the results limited and not entirely suitable for real life operating conditions of typical hypoid gear pairs of vehicular differentials, which is of interest in the current paper. Xu and Kahraman [2] performed numerical prediction of power losses and consequently the film thickness for highly loaded hypoid gear pairs. However, in their study only the one-dimensional Reynolds equation was employed. Consequently, the effect of lubricant side leakage in the passage through the contact was ignored. A more recent study by Mohammadpour et al. [3] employed realistic gear geometry data (through the use of TCA) for calculation of film thickness time history through mesh. The two-dimensional Reynolds equation, accounting for the side leakage of the lubricant, was solved numerically. It was shown that the side leakage component of the entraining velocity can significantly influence the film thickness. With regard to hypoid gear dynamics, several studies should be mentioned. Wang and Lim [4] studied the dynamic response of hypoid gear pairs under the influence of time varying meshing stiffness. Yang and Lim [5] created a model able to predict the dynamic response of a hypoid gear pair by taking into account the lateral translations of their shafts due to the compliance of the supporting bearings. Karagiannis et al. [6-7] studied the dynamics of automotive differential hypoid gear pairs by taking into account the velocity dependent resistive torque at the gear caused by aerodynamic drag and tyre-road rolling resistance. The study integrated the gear dynamics with the generated viscous and boundary conjunctional friction

Phenotypic and molecular assessment of seven patients with 6p25 deletion syndrome: Relevance to ocular dysgenesis and hearing impairment

BACKGROUND: Thirty-nine patients have been described with deletions involving chromosome 6p25. However, relatively few of these deletions have had molecular characterization. Common phenotypes of 6p25 deletion syndrome patients include hydrocephalus, hearing loss, and ocular, craniofacial, skeletal, cardiac, and renal malformations. Molecular characterization of deletions can identify genes that are responsible for these phenotypes. METHODS: We report the clinical phenotype of seven patients with terminal deletions of chromosome 6p25 and compare them to previously reported patients. Molecular characterization of the deletions was performed using polymorphic marker analysis to determine the extents of the deletions in these seven 6p25 deletion syndrome patients. RESULTS: Our results, and previous data, show that ocular dysgenesis and hearing impairment are the two most highly penetrant phenotypes of the 6p25 deletion syndrome. While deletion of the forkhead box C1 gene (FOXC1) probably underlies the ocular dysgenesis, no gene in this region is known to be involved in hearing impairment. CONCLUSIONS: Ocular dysgenesis and hearing impairment are the two most common phenotypes of 6p25 deletion syndrome. We conclude that a locus for dominant hearing loss is present at 6p25 and that this locus is restricted to a region distal to D6S1617. Molecular characterization of more 6p25 deletion patients will aid in refinement of this locus and the identification of a gene involved in dominant hearing loss

Contrasting influences of inundation and land use on the rate of floodplain restoration

This study examined the assisted natural restoration of native vegetation in an Australian floodplain wetland where flows were reinstated and the river was reconnected to the floodplain, following cessation of agricultural cultivation. Extant vegetation was surveyed three times during an inundation event at plots with different land‐use histories. Restoration rate was more influenced by past land use than long‐term inundation frequency and success decreased with antecedent land‐use intensity. Prolonged land‐use history (>3 years cultivation) restricted restoration success. Sites with longer cultivation histories tended to have fewer aquatic species, more terrestrial species and exotic species. For example, amphibious responders with floating leaves were found only in reference plots and less frequently in farmed treatment plots. In this scenario, increased persistence of exotics and dryland species suggested alternative trajectories. Fields with a short land‐use history (1–3 years of clearing and cultivation) resembled undisturbed floodplain communities, consistent with a ‘field of dreams’ hypothesis. Although river–floodplain reconnections can restore wetlands, legacy effects of past land use may limit the pace and outcomes of restoration.Australian Postgraduate AwardAustralian Research Council. Grant Number: DE120102221ARC Centre of Excellence for Environmental Decisions Australian Research Council Linkage Project. Grant Number: LP088416

Spinocerebellar ataxia type 7 in South Africa: Epidemiology, pathogenesis and therapy

Disorders of the nervous system represent a significant proportion of the global burden of non-communicable diseases, due to the trend towards ageing populations. The Department (now Division) of Human Genetics at the University of Cape Town (UCT) has been involved in pioneering research into these diseases since the appointment of Prof. Peter Beighton as Head of Department in 1972. Beighton’s emphasis on understanding the genetic basis of disease laid the groundwork for investigations into several monogenic neurodegenerative conditions, including Huntington’s disease and the polyglutamine spinocerebellar ataxias (SCAs). In particular, SCA7, which occurs at an unusually high frequency in the South African (SA) population, was identified as a target for further research and therapeutic development. Beginning with early epidemiological surveys, the SCA7 project progressed to molecular genetics-based investigations, leading to the identification of a founder effect in the SA SCA7 patient population in the mid-2000s. Capitalising on the founder haplotype shared by many SCA7 patients, UCT researchers went on to develop the first population-specific gene-silencing approach for the disease. More recently, efforts have shifted to the development of a more accurate model to decipher the precise mechanisms of neurodegeneration, using induced pluripotent stem cells derived from SA SCA7 patients. In many ways, the SA SCA7 journey reflects the legacy and vision of Prof. Peter Beighton, and his efforts to establish world-class, collaborative research into diseases affecting the African continent.

LONG-RUN PERSISTENCE IN RESERVOIR INFLOWS: EMPIRICAL MODE DECOMPOSITION IN SYDNEY AND MELBOURNE

ABSTRACT This paper quantifies long-run hydrological persistence in reservoir inflows to two regions: Melbourne and Sydney. We use a relatively new approach in hydrology, Empirical Mode Decomposition (EMD). Our three key results are summarised below: (1) For Melbourne and Sydney inflows, 57-66% of total variance was accounted for by periodicities <10 years; 20-21% of total variance was attributable to periodicities >10 years; and 14-22

Towards a fair comparison of statistical and dynamical downscaling in the framework of the EURO-CORDEX initiative

Both statistical and dynamical downscaling methods are well established techniques to bridge the gap between the coarse information produced by global circulation models and the regional-to-local scales required by the climate change Impacts, Adaptation, and Vulnerability (IAV) communities. A number of studies have analyzed the relative merits of each technique by inter-comparing their performance in reproducing the observed climate, as given by a number of climatic indices (e.g. mean values, percentiles, spells). However, in this paper we stress that fair comparisons should be based on indices that are not affected by the calibration towards the observed climate used for some of the methods. We focus on precipitation (over continental Spain) and consider the output of eight Regional Climate Models (RCMs) from the EURO-CORDEX initiative at 0.44? resolution and five Statistical Downscaling Methods (SDMs) ?analog resampling, weather typing and generalized linear models? trained using the Spain044 observational gridded dataset on exactly the same RCM grid. The performance of these models is inter-compared in terms of several standard indices ?mean precipitation, 90th percentile on wet days, maximum precipitation amount and maximum number of consecutive dry days? taking into account the parameters involved in the SDM training phase. It is shown, that not only the directly affected indices should be carefully analyzed, but also those indirectly influenced (e.g. percentile-based indices for precipitation) which are more difficult to identify. We also analyze how simple transformations (e.g. linear scaling) could be applied to the outputs of the uncalibrated methods in order to put SDMs and RCMs on equal footing, and thus perform a fairer comparison.We acknowledge the World Climate Research Programme’s Working Group on Regional Climate, and theWorking Group on CoupledModelling, former coordinating body of CORDEX and responsible panel for CMIP5. We also thank the climate modeling groups (listed in Table 1 of this paper) for producing and making available their model output. We also acknowledge the Earth System Grid Federation infrastructure and AEMET and University of Cantabria for the Spain02 dataset (available at http: //www.meteo.unican.es/en/datasets/spain02). All the statistical downscaling experiments have been computed using theMeteoLab software (http://www.meteo.unican.es/software/meteolab), which is an open-source Matlab toolbox for statistical downscaling. This work has been partially supported by CORWES (CGL2010-22158-C02) and EXTREMBLES (CGL2010-21869) projects funded by the Spanish R&D programme. AC thanks the Spanish Ministry of Economy and Competitiveness for the funding provided within the FPI programme (BES-2011-047612 and EEBB-I-13-06354), JMG acknowledges the support from the SPECS project (FP7-ENV-2012-308378) and JF is grateful to the EUPORIAS project (FP7-ENV-2012-308291). We also thank three anonymous referees for their useful comments that helped to improve the original manuscript

An Early Study on the Mechanisms that Allow Tissue-Engineered Vascular Grafts to Resist Intimal Hyperplasia

Intimal hyperplasia is one of the prominent failure mechanisms for arteriovenous fistulas and arteriovenous access grafts. Human tissue-engineered vascular grafts (TEVGs) were implanted as arteriovenous grafts in a novel baboon model. Ultrasound was used to monitor flow rates and vascular diameters throughout the study. Intimal hyperplasia in the outflow vein of TEVGs was assessed at the anastomosis and at juxta-anastomotic regions via histological analysis, and was compared to intimal hyperplasia with polytetrafluoroethylene (PTFE) grafts in the baboon model and in literature reports from other animal models. Less venous intimal hyperplasia was observed in histological sections with arteriovenous TEVGs than with arteriovenous PTFE grafts. TEVGs were associated with a mild, noninflammatory intimal hyperplasia. The extent of intimal tissue that formed with TEVG placement correlated with the rate of blood flow through tissue engineered vascular grafts at 2 weeks postimplant. Outflow vein dilatation was observed with increased flow rate. Both mid-graft flow rates and outflow vein diameters reached a plateau by week 4, which suggested that venous remodeling and intimal hyperplasia largely occurred within the first 4 weeks of implant in the baboon model. Given their compliant and noninflammatory nature, TEVGs appear resistant to triggers for venous intimal hyperplasia that are common for PTFE arteriovenous grafts, including (1) abundant proinflammatory macrophage populations that are associated with PTFE grafts and (2) compliance mismatch between PTFE grafts and the outflow vein. Our findings suggest that arteriovenous TEVGs develop only a mild form of venous intimal hyperplasia, which results from the typical hemodynamic changes that are associated with arteriovenous settings