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The interconversion of charge and spin currents via spin-Hall effect is essential for spintronics. Energy-efficient and deterministic switching of magnetization can be achieved when spin polarizations of these spin currents are collinear with the magnetization. However, symmetry conditions generally restrict spin polarizations to be orthogonal to both the charge and spin flows. Spin polarizations can deviate from such direction in nonmagnetic materials only when the crystalline symmetry is reduced. Here, we show control of the spin polarization direction by using a non-collinear antiferromagnet Mn3GaN, in which the triangular spin structure creates a low magnetic symmetry while maintaining a high crystalline symmetry. We demonstrate that epitaxial Mn3GaN/permalloy heterostructures can generate unconventional spin-orbit torques at room temperature corresponding to out-of-plane and Dresselhaus-like spin polarizations which are forbidden in any sample with two-fold rotational symmetry. Our results demonstrate an approach based on spin-structure design for controlling spin-orbit torque, enabling high-efficient antiferromagnetic spintronics., In the typical spin-hall effect, spin-current, charge current, and spin polarisation are all mutually perpendicular, a feature enforced by symmetry. Here, using an anti-ferromagnet with a triangular spin structure, the authors demonstrate a spin-hall effect without a perpendicular spin alignment.

Bulk single-crystal relaxor-ferroelectrics, like Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT), are widely known for their large piezoelectricity. This is attributed to polarization rotation which is facilitated by the presence of various crystal symmetries for compositions near a morphotropic phase boundary (MPB). Relaxor-ferroelectric thin films, which are necessary for low-voltage applications, suffer a reduction in their piezoelectric response due to clamping by the passive substrate. To understand the microscopic behavior of this adverse phenomenon, we employ AC electric field driven in-operando synchrotron x-ray diffraction (XRD) on patterned device structures to investigate the piezoelectric domain behavior under an electric field for both a clamped (001) PMN-PT thin film on Si and a (001) PMN-PT membrane released from its substrate. In the clamped film, the substrate inhibits the field induced rhombohedral (R) to tetragonal (T) phase transition resulting in a reversible R to Monoclinic (M) transition with a reduced longitudinal piezoelectric coefficient d33 < 100 pm/V. Releasing the film from the substrate results in recovery of the R to T transition and results in a d33 > 1000 pm/V. Using diffraction with spatial mapping, we find that lateral constraints imposed by the boundary between active and inactive material also inhibits the R to T transition. Phase-field calculations on both clamped and released PMN-PT thin films simulate our experimental findings. Resolving the suppression of thin film piezoelectric response is critical to their application in piezo-driven technologies.

As a hallmark of electronic correlation, spin-charge interplay underlies many emergent phenomena in doped Mott insulators, such as high-temperature superconductivity, whereas the half-filled parent state is usually electronically frozen with an antiferromagnetic order that resists external control. We report on the observation of a new positive magnetoresistance that probes the staggered susceptibility of a pseudospin-half square-lattice Mott insulator built as an artificial SrIrO3/SrTiO3 superlattice. Its size is particularly large in the high-temperature insulating paramagnetic phase near the N\'eel transition. This novel magnetoresistance originates from a collective charge response to the large longitudinal spin fluctuations under a linear coupling between the external magnetic field and the staggered magnetization enabled by strong spin-orbit interaction. Our results demonstrate a magnetic control of the binding energy of the fluctuating particle-hole pairs in the Slater-Mott crossover regime analogous to the BCS-to-Bose-Einstein condensation crossover of ultracold-superfluids., Comment: Accepted by Nature communications

Abnormal protein aggregation has been linked to many neurodegenerative diseases, including Parkinson’s disease (PD). The main pathological hallmark of PD is the formation of Lewy bodies (LBs) and Lewy neurites, both of which contain the presynaptic protein alpha-synuclein (α-syn). Under normal conditions, native α-syn exists in a soluble unfolded state but undergoes misfolding and aggregation into toxic aggregates under pathological conditions. Toxic α-syn species, especially oligomers, can cause oxidative stress, membrane penetration, synaptic and mitochondrial dysfunction, as well as other damage, leading to neuronal death and eventually neurodegeneration. Early diagnosis and treatments targeting PD pathogenesis are urgently needed. Given its critical role in PD, α-syn is an attractive target for the development of both diagnostic tools and effective therapeutics. This review summarizes the progress toward discovering imaging probes and aggregation inhibitors for α-syn. Relevant strategies and techniques in the discovery of α-syn-targeted drugs are also discussed.

The coupling of ordered electronic phases with lattice, spin, and orbital degrees of freedom are of central interest in strongly correlated systems. Their interplay has been intensively studied from femtosecond to picosecond time scales, while their dynamics beyond nanoseconds are usually assumed to follow lattice cooling. Here, we report an unusual slowing down of the recovery of an electronic phase across a first-order phase transition. Following optical excitation, the recovery time of both transient optical reflectivity and X-ray diffraction intensity from the charge-ordered superstructure in a La1/3Sr2/3FeO3 thin film increases by orders of magnitude as the sample temperature approaches the phase transition temperature. In this regime, the recovery time becomes much longer than the lattice cooling time. The combined experimental and theoretical investigation shows that the slowing down of electronic recovery corresponds to the pseudo-critical dynamics that originates from magnetic interactions close to a weakly first-order phase transition., Unusual electronic behavior can emerge in complex oxides due to strong coupling between charge, magnetic and lattice degrees of freedom. Zhu et al. observe separation of electronic and lattice equilibration times in La1/3Sr2/3FeO3 as magnetic interactions make the recovery of charge order much slower than lattice relaxation.

Polar metals, commonly defined by the coexistence of polar crystal structure and metallicity, are thought to be scarce because the long-range electrostatic fields favoring the polar structure are expected to be fully screened by the conduction electrons of a metal. Moreover, reducing from three to two dimensions, it remains an open question whether a polar metal can exist. Here we report on the realization of a room temperature two-dimensional polar metal of the B-site type in tri-color (tri-layer) superlattices BaTiO3/SrTiO3/LaTiO3. A combination of atomic resolution scanning transmission electron microscopy with electron energy-loss spectroscopy, optical second harmonic generation, electrical transport, and first-principles calculations have revealed the microscopic mechanisms of periodic electric polarization, charge distribution, and orbital symmetry. Our results provide a route to creating all-oxide artificial non-centrosymmetric quasi-two-dimensional metals with exotic quantum states including coexisting ferroelectric, ferromagnetic, and superconducting phases., Materials that combine metallic behaviour with stable electric polarization are scarce despite being proposed in the 1960s. Here the authors engineer a perovskite heterostructure where 2D polar metallic behavior coexists with built-in electric polarization from the displacement of B-site titanium cations.

Brain regions that regulate fluid satiation are not well characterized, yet are essential for understanding fluid homeostasis. We found that oxytocin-receptor-expressing neurons in the parabrachial nucleus of mice (OxtrPBN neurons) are key regulators of fluid satiation. Chemogenetic activation of OxtrPBN neurons robustly suppressed noncaloric fluid intake, but did not decrease food intake after fasting or salt intake following salt depletion; inactivation increased saline intake after dehydration and hypertonic saline injection. Under physiological conditions, OxtrPBN neurons were activated by fluid satiation and hypertonic saline injection. OxtrPBN neurons were directly innervated by oxytocin neurons in the paraventricular hypothalamus (OxtPVH neurons), which mildly attenuated fluid intake. Activation of neurons in the nucleus of the solitary tract substantially suppressed fluid intake and activated OxtrPBN neurons. Our results suggest that OxtrPBN neurons act as a key node in the fluid satiation neurocircuitry, which acts to decrease water and/or saline intake to prevent or attenuate hypervolemia and hypernatremia., The authors show that oxytocin-receptor-expressing neurons in the parabrachial nucleus are key regulators of fluid homeostasis that suppress fluid intake when activated, but do not decrease food intake after fasting or salt intake after salt depletion.

The use of multiple imputation has increased markedly in recent years, and journal reviewers may expect to see multiple imputation used to handle missing data. However in randomized trials, where treatment group is always observed and independent of baseline covariates, other approaches may be preferable. Using data simulation we evaluated multiple imputation, performed both overall and separately by randomized group, across a range of commonly encountered scenarios. We considered both missing outcome and missing baseline data, with missing outcome data induced under missing at random mechanisms. Provided the analysis model was correctly specified, multiple imputation produced unbiased treatment effect estimates, but alternative unbiased approaches were often more efficient. When the analysis model overlooked an interaction effect involving randomized group, multiple imputation produced biased estimates of the average treatment effect when applied to missing outcome data, unless imputation was performed separately by randomized group. Based on these results, we conclude that multiple imputation should not be seen as the only acceptable way to handle missing data in randomized trials. In settings where multiple imputation is adopted, we recommend that imputation is carried out separately by randomized group.

Automatic speech recognition (ASR), audio quality, and loudness are key performance indicators (KPIs) in smart speakers. To improve all these KPIs, audio dynamics processing is a crucial component in related systems. Unfortunately, single-band and existing multiband dynamics processing (MBDP) schemes fail to maximize bass and loudness but even produce unwanted peaks, distortions, and nonlinear echo so that an optimized ASR performance cannot be achieved. It has been a goal in both industry and academia to find a better audio dynamics processing for mitigating these problems. To provide such a desired solution, this paper proposes a novel reconfigurable multitask MBDP scheme through a global optimization framework. Through extensive testing, we show the accuracy and effectiveness of the proposed scheme in terms of bass and loudness maximization, distortion and nonlinear echo reduction, browning-out prevention, and significant ASR performance improvement., 5 pages, ICASSP 2019 paper

In pursuit of creating cuprate-like electronic and orbital structures, artificial heterostructures based on LaNiO$_3$ have inspired a wealth of exciting experimental and theoretical results. However, to date there is a very limited experimental understanding of the electronic and orbital states emerging after interfacial charge-transfer and their connections to the modified band structure at the interface. Towards this goal, we have synthesized a prototypical superlattice composed of correlated metal LaNiO$_3$ and doped Mott insulator LaTiO$_{3+\delta}$, and investigated its electronic structure by resonant X-ray absorption spectroscopy combined with X-ray photoemission spectroscopy, electrical transport and theory calculations. The heterostructure exhibits interfacial charge-transfer from Ti to Ni sites giving rise to an insulating ground state with orbital polarization and $e_\textrm{g}$ orbital band splitting. Our findings demonstrate how the control over charge at the interface can be effectively used to create exotic electronic, orbital and spin states., Comment: 4 figures

Fluid satiation, or quenching of thirst, is a critical homeostatic signal to stop drinking; however, its underlying neurocircuitry is not well characterized. Cutting‐edge genetically encoded tools and techniques are now enabling researchers to pinpoint discrete neuronal populations that control fluid satiation, revealing that hindbrain regions, such as the nucleus of the solitary tract, area postrema, and parabrachial nucleus, primarily inhibit fluid intake. By contrast, forebrain regions such as the lamina terminalis, primarily stimulate thirst and fluid intake. One intriguing aspect of fluid satiation is that thirst is quenched tens of minutes before water reaches the circulation, and the amount of water ingested is accurately calibrated to match physiological needs. This suggests that ‘preabsorptive’ inputs from the oropharyngeal regions, esophagus or upper gastrointestinal tract anticipate the amount of fluid required to restore fluid homeostasis, and provide rapid signals to terminate drinking once this amount has been consumed. It is likely that preabsorptive signals are carried via the vagal nerve to the hindbrain. In this review, we explore our current understanding of the fluid satiation neurocircuitry, its inputs and outputs, and its interconnections within the brain, with a focus on recent studies of the hindbrain, particularly the parabrachial nucleus.

Mandatory iodine fortification of bread was introduced in 2009 in Australia in response to the reemergence of iodine deficiency. The aim of this study was to assess iodine intake, urinary iodine concentration (UIC) and their correlation in pregnant women (n = 783) recruited from South Australia 2 years following mandatory iodine fortification. Total iodine intake (food and supplements) and UIC were assessed at study entry (150 μg/L.

Elastic strain is potentially an important approach in tuning the properties of the improperly multiferroic hexagonal ferrites, the details of which have however been elusive due to the experimental difficulties. Employing the method of restrained thermal expansion, we have studied the effect of isothermal biaxial strain in the basal plane of h-LuFeO3 (001) films. The results indicate that a compressive biaxial strain significantly enhances the ferrodistortion, and the effect is larger at higher temperatures. The compressive biaxial strain and the enhanced ferrodistortion together, cause an increase in the electric polarization and a reduction in the canting of the weak ferromagnetic moments in h-LuFeO3, according to our first principle calculations. These findings are important for understanding the strain effect as well as the coupling between the lattice and the improper multiferroicity in h-LuFeO3. The experimental elucidation of the strain effect in h-LuFeO3 films also suggests that the restrained thermal expansion can be a viable method to unravel the strain effect in many other epitaxial thin film materials.

The influence of shallow core-level hybridization on the electronic structure of the post-transition metal oxides ZnO, CdO, In 2 O 3 , and SnO 2 has been investigated using high-resolution soft x-ray emission and absorptionspectroscopies. Synchrotron radiation excited O K α emission spectra provide a direct measure of the O 2p partial density of states and shallow core-level hybridization for this series of transparent conducting materials and reveal significant mixing of O 2p and shallow-core metal d states for ZnO, CdO, and In 2 O 3 . The experimental data are compared with local density approximation and tight-binding band structure calculations and with previous experimental determinations of direct and indirect band gaps. Rocksalt CdO, bixbyite In 2 O 3 , and rutile SnO 2 all adopt structures with metal cations in sites with locally centrosymmetric coordination. This prevents hybridization of O 2p states with metal 4d states at the zone center, but mixing away from Γ leads to indirect band gaps for CdO and In 2 O 3 . A revised value for the lowest indirect band gap in CdO is proposed and the overall trends in the band gap are discussed in terms of the separation between O 2p and metal 4d states. The experimental investigation has been extended to study the effects of Sn doping in In 2 O 3 .

Purpose: Here we describe some available statistical models and illustrate their use for analysis of arthroplasty registry data in the presence of the competing risk of death, when the influence of covariates on the revision rate may be different to the influence on the probability (that is, risk) of the occurrence of revision. Patients and methods: Records of 12,525 patients aged 75–84 years who had received hemiarthroplasty for fractured neck of femur were obtained from the Australian Orthopaedic Association National Joint Replacement Registry. The covariates whose effects we investigated were: age, sex, type of prosthesis, and type of fixation (cementless or cemented). Extensions of competing risk regression models were implemented, allowing the effects of some covariates to vary with time. Results The revision rate was significantly higher for patients with unipolar than bipolar prostheses (HR = 1.38, 95% CI: 1.01– 1.89) or with monoblock than bipolar prostheses (HR = 1.45, 95% CI: 1.08–1.94). It was significantly higher for the younger age group (75–79 years) than for the older one (80–84 years) (HR = 1.28, 95% CI: 1.05–1.56) and higher for males than for females (HR = 1.37, 95% CI: 1.09–1.71). The probability of revision, after correction for the competing risk of death, was only significantly higher for unipolar prostheses than for bipolar prostheses, and higher for the younger age group. The effect of fixation type varied with time; initially, there was a higher probability of revision for cementless prostheses than for cemented prostheses, which disappeared after approximately 1.5 years. Interpretation: When accounting for the competing risk of death, the covariates type of prosthesis and sex influenced the rate of revision differently to the probability of revision. We advocate the use of appropriate analysis tools in the presence of competing risks and when covariates have time-dependent effects. Refereed/Peer-reviewed

Background: Ranibizumab, a vascular endothelial growth factor (VEGF) inhibitor, is used in the treatment of agerelated macular degeneration. Inhibition of VEGF has an anti-angiogenic action and is associated with thrombogenicity, thus, myocardial infarction and ischaemic stroke are potential side effects of VEGF inhibitors. Conclusion: This case-series analysis suggests an increased risk of hospitalisation for ischaemic stroke for patients receiving ranibizumab in the 31-60 days risk period. Studies with larger populations are required to confirm the risk in the 1-30 days risk period. No evidence of increased risk of hospitalisation for MI was observed. Methods: The self-controlled case series design was used, including subjects exposed to ranibizumab (Anatomical Therapeutic Chemical [ATC] code S01LA04) who were hospitalized for IS (International Classification of Diseases, tenth edition [ICD-10] code I63) or the combined endpoint of stroke or transient ischaemic attack (TIA) (ICD-10 code G45) or MI (ICD-10 code I21) were identified between August 2007 and March 2013. Rate ratios in exposed periods compared with unexposed periods were calculated using conditional Poisson regression. Objective: Our objective was to assess the association between use of ranibizumab and risk of hospitalisation for ischaemic stroke (IS) and myocardial infarction (MI). Results: A total of 323 subjects received ranibizumab and were hospitalized for IS, 490 for IS or TIA, and 391 for MI. Median period of exposure was 8-9 months with follow-up times of approximately 2.8 years. No elevated risk of IS was seen in the 1-30 days post initiation (incidence rate ratio [IRR] 1.36; 95 % confidence interval [CI] 0.98-1.88); however, elevated risk was observed for those who received therapy for 31-60 days (IRR 1.91; 95 % CI 1.13-3.24). Sensitivity analyses adjusting for time-varying confounders found elevated risk in both the 1-30 days and 31-60 days periods. Similar results to those for IS were observed for the combined endpoint of IS or TIA. No association was seen for MI in either time period (1-30 days IRR 0.90, 95 % CI 0.65-1.23; 31-60 days IRR 0.98, 95 % CI 0.54-1.79). Refereed/Peer-reviewed

Using combined theoretical and experimental approaches, we studied the structural and electronic origin of the magnetic structure in hexagonal LuFeO$_3$. Besides showing the strong exchange coupling that is consistent with the high magnetic ordering temperature, the previously observed spin reorientation transition is explained by the theoretically calculated magnetic phase diagram. The structural origin of this spin reorientation that is responsible for the appearance of spontaneous magnetization, is identified by theory and verified by x-ray diffraction and absorption experiments., 5 pages, 2 tables and 4 figures, Please contact us for the supplementary material. Accepted in Phys. Rev. B, in production

Background The Australian Government Department of Veterans’ Affairs (DVA) funds an ongoing health promotion based program to improve use of medicines and related health services, which implements interventions that include audit and feedback in the form of patient-specific feedback generated from administrative claims records. We aimed to determine changes in medicine use as a result of the program. Methods The program provides targeted patient-specific feedback to medical practitioners. The feedback is supported with educational material developed by a clinical panel, subject to peer review and overseen by a national editorial committee. Veterans who meet target criteria also receive educational brochures. The program is supported by a national call centre and ongoing national consultation. Segmented regression analyses (interrupted time series) were undertaken to assess changes in medication use in targeted veterans pre and post each intervention. Results 12 interventions were included; three to increase medicine use, seven which aimed to reduce use, and two which had combination of messages to change use. All programs that aimed to increase medicine use were effective, with relative effect sizes at the time of the intervention ranging from 1% to 8%. Mixed results were seen with programs aiming to reduce inappropriate medicine use. Highly specific programs were effective, with relative effect sizes at the time of the intervention of 10% decline in use of NSAIDs in high risk groups and 14% decline in use of antipsychotics in dementia. Interventions targeting combinations of medicines, including medicine interactions and potentially inappropriate medicines in the elderly did not change practice significantly. Interventions with combinations of messages targeting multiple components of practice had an impact on one component, but not all components targeted. Conclusions The Veterans’ MATES program showed positive practice change over time, with interventions increasing use of appropriate medicines where under-use was evident and reduced use of inappropriate medicines when single medicines were targeted. Combinations of messages were less effective, suggesting specific messages focusing on single medicines are required to maximise effect. The program provides a model that could be replicated in other settings.

Background Antipsychotics are frequently and increasingly prescribed to treat the behavioural symptoms associated with dementia despite their modest efficacy. Evidence regarding the potential adverse events of antipsychotics is limited and little is known about the longer-term safety of these medicines in the elderly. The aim of this review was to determine the impact of the choice of observational study design and methods used to control for confounding on the measurement of antipsychotic risks in elderly patients. Methods We searched PUBMED and the Cochrane controlled trials register for double-blind randomised controlled trials (RCTs), meta-analyses and published observational studies of antipsychotics. Results Forty four studies were identified for the endpoints; death, cerebrovascular events, hip fracture and pneumonia. RCTs found a 20% to 30% increased risk of death, or an absolute increase of 1extra death per 100 patients with atypical antipsychotics compared to non-use. Cohort and instrumental variable analyses estimated between 2 to 7 extra deaths per 100 patients with conventional compared to atypical antipsychotics. RCTs found a 2 to 3 times increased risk of all cerebrovascular events with atypical antipsychotics compared to placebo and no association with serious stroke that required hospitalisation. Observational studies using cohort and self-controlled case-series designs reported similar results; no association where the endpoint was stroke causing hospitalisation and a doubling of risk when minor stroke was included. No RCTs were available for the outcome of hip fracture or pneumonia. Observational studies reported a 20% to 40% increased risk of hip fracture with both antipsychotic classes compared to non-use. The risk of pneumonia was a 2 to 3 times greater with both classes compared to non-use while a self-controlled case-series study estimated a 60% increased risk. Conventional antipsychotics were associated with a 50% greater hip fracture risk than atypical antipsychotics, while the risk of pneumonia was similar between the classes. Conclusions Choice of observational study design is critical in studying the adverse effects of antispychotics. Cohort and instrumental variable analyses gave more consistent results to clinical studies for mortality outcomes as have self-controlled case-series for the risk of cerebrovascular events and stroke. Observational evidence has highlighted the potential for antipsychotics to be associated with serious adverse events that were not reported in RCTs including hip fracture and pneumonia. Good quality observational studies are required, that employ appropriate study designs that are robust towards unmeasured confounding, to confirm the potential excess risk of hip fracture and pneumonia with antipsychotics.

Background: Preterm human milk–fed infants often experience suboptimal growth despite the use of human milk fortifier (HMF). The extra protein supplied in fortifiers may be inadequate to meet dietary protein requirements for preterm infants. Objective: We assessed the effect of human milk fortified with a higher-protein HMF on growth in preterm infants. Design: This is a randomized controlled trial in 92 preterm infants born at ,31 wk gestation who received maternal breast milk that was fortified with HMF containing 1.4 g protein/100 mL (higherprotein group) or 1.0 g protein/100 mL (current practice) until discharge or estimated due date, whichever came first. The HMFs used were isocaloric and differed only in the amount of protein or carbohydrate. Length, weight, and head-circumference gains were assessed over the study duration. Results: Length gains did not differ between the higher- and standardprotein groups (mean difference: 0.06 cm/wk; 95% CI: 20.01, 0.12 cm/wk; P = 0.08). Infants in the higher-protein group achieved a greater weight at study end (mean difference: 220 g; 95% CI: 23, 419 g; P = 0.03). Secondary analyses showed a significant reduction in the proportion of infants who were less than the 10th percentile for length at the study end in the higher-protein group (risk difference: 0.186; 95% CI: 0.370, 0.003; P = 0.047). Conclusions: A higher protein intake results in less growth faltering in human milk–fed preterm infants. It is possible that a higher-protein fortifier than used in this study is needed. This trial was registered with the Australian New Zealand Clinical Trials Registry (http:// www.anzctr.org.au/) as ACTRN12606000525583. Am J Clin Nutr doi: 10.3945/ajcn.111.026351.

George Mnatzaganian,1 Philip Ryan,1,2 Paul E Norman,3 David C Davidson,4 Janet E Hiller1,51School of Population Health and Clinical Practice, Discipline of Public Health, 2Data Management and Analysis Centre, The University of Adelaide, South Australia; 3School of Surgery, University of Western Australia, Western Australia; 4Royal Adelaide Hospital, South Australia; 5Faculty of Health Sciences, Australian Catholic University, Fitzroy, Victoria, AustraliaBackground: We retrospectively assessed the independent effects of patient and clinical factors on length of stay and all-cause 90-day, one-year, and two-year readmission following elective total joint replacement. We also evaluated the independent association between length of stay and readmission with postoperative five-year mortality.Methods: Longitudinal data from 819 men who had had total joint replacement were integrated with validated hospital morbidity data and mortality records. Length of stay, readmission, and mortality following total joint replacement were each modeled using multivariable proportional hazards regression.Results: Mean age at surgery was 76.3 ± 4.3 years. Median length of stay following total joint replacement decreased by 25% from 12 days in 1997–1998 to nine days in 2005–2007. Age, inhospital complications, total knee replacement, private hospital, and increased body weight were significantly associated with longer stay. A dose-response relationship between weight and length of stay was observed (P = 0.003). Crude 90-day, one-year, and two-year readmission rates were 17.3%, 47.4%, and 65.0%, respectively. Ninety-day readmission was associated with comorbidity, inhospital complications, and treatment in public hospitals. Age, comorbidity, socioeconomic disadvantage, and increased weight significantly increased the risk of one-year and two-year readmission. Patients with a body mass index≥ 30 kg/m2 were 34% more likely to be readmitted within two years compared with those having a body mass index of 18.5–24.9 kg/m2. All-cause one-year and two-year readmission rates were significantly higher in patients undergoing a total knee replacement than those undergoing a total hip replacement. No independent associations between length of stay and all-cause readmission or mortality were observed. All-cause 90-day and one-year readmission independently increased the risk of long-term postoperative mortality.Conclusion: After adjusting for confounding factors, including age, comorbidity, obesity, and inhospital complications, length of stay was not independently associated with post-discharge readmission or death. We report that the obese, those having total knee replacement, and the socioeconomically disadvantaged are the highest consumers of hospital resources following elective total joint replacement in elderly men. Our findings may assist clinicians in better selection of elderly patients for surgery, and informing them about their individual level of risk.Keywords: elderly, total joint replacement, obesity, length of stay, all-cause readmission

Objectives The main objectives of this study were to validate the hospital morbidity data (HMD) and to compare the performance of three comorbidity adjusting methods in predicting 1-year and 5-year all-cause mortality in a male general hospital population in Western Australia (WA). Study Design and Setting Population-based data were integrated with WA-linked data system. Deyo–Charlson Index, Enhanced-Charlson Index, and Elixhauser's method measured comorbidity. Mortality was modeled using Cox regression, and model discrimination was assessed by Harrell's C statistics. Results The HMD were most likely to identify major comorbidities, such as cancer, myocardial infarction, diabetes mellitus, and major operations. The presence of comorbidity was independently associated with an increased risk of adverse outcomes. All models achieved acceptable levels of discrimination (Harrell's C: 0.70–0.76). The Enhanced-Charlson Index matched the Deyo–Charlson Index in predicting mortality. Elixhauser's method outperformed the other two. Including information from past admissions achieved nonsignificant improvement in model discrimination. A dose-response effect was observed in the effect of repeated episodes on risk of 5-year mortality. Conclusion Comorbidities diagnosed at different points in time may have different associations with the risk of adverse outcomes. More research is required to integrate the effect of repeated episodes in currently used methods that measure and adjust for comorbidity.

Background: Previous studies have shown that migrants have lower cancer mortality rates compared to the Australian-born population, particularly for colorectal and breast cancers, which are associated with an affluent lifestyle. This study seeks to update knowledge in this field by examining mortality from colorectal, stomach, lung, melanoma, breast and bladder cancers, as well as all cancers combined between 1981 and 2007. Methods: Data were obtained from the Australian Bureau of Statistics. Average annual age and sex-standardised mortality rates were calculated for each region of birth, period of death registration and cancer site. Results: Generally, mortality rates declined over the study period for most conditions for the majority of migrant groups. Notable exceptions included migrants from South Eastern Europe and Eastern Europe who experienced a significant increase in mortality due to all cancers combined and Australian-born individuals who recorded a significant increase in mortality due to melanoma of the skin. Migrants generally had more favourable cancer mortality outcomes, particularly for colorectal cancer and melanoma. Migrants from Southern Europe, South Eastern Europe, Chinese Asia and Southern Asia had the greatest advantage. However, migrants displayed higher rates of stomach, lung and bladder cancers than the Australian-born population. Conclusion: The migrant advantage can in part be explained by the protective effects of diet, lifestyle and reproductive behaviours. Possible explanations for why some migrants display greater mortality from stomach and bladder cancer include the consumption of abrasive, salted and preserved foods and higher rates of smoking. Greater emphasis should be placed on targeting at-risk migrant groups through screening and education programs at migrant resource centres and community groups. The study calls for further research to explain the observed trends, which has the potential to uncover important risk and protective factors. Refereed/Peer-reviewed

Introduction: No consent for health and medical research is appropriate when the criteria for a waiver of consent are met, yet some ethics committees and data custodians still require informed consent. Methods: A single-blind parallel-group randomised controlled trial: 1129 families of children born at a South Australian hospital were sent information explaining data linkage of childhood immunisation and hospital records for vaccine safety surveillance with 4 weeks to opt in or opt out by reply form, telephone or email. A subsequent telephone interview gauged the intent of 1026 parents (91%) in relation to their actions and the sociodemographic differences between participants and non-participants in each arm. Results: The participation rate was 21% (n=120/564) in the opt-in arm and 96% (n=540/565) in the opt-out arm (Ï[double dagger]2 (1 df) = 567.7, p

Objective: Clinical asthma guidelines recommend spirometry for asthma diagnosis, but there is inconsistent evidence about benefits to patients in using it for ongoing management. Our aim was to determine whether training in the use of spirometry for management of asthma provided better health outcomes and improved the quality of care in the primary care setting. Design: Pragmatic, cluster randomized controlled trial. Setting: General practices in two states of Australia. Participants: Forty practices and 397 adults with asthma. Intervention: The staff of 26 intervention practices received comprehensive spirometry training. Fourteen control practices provided usual care. Main Outcome Measures: Primary outcome measures were quality of life, self-reported asthma symptoms and lung function. Secondary measures related to the process of care (e.g. performance of spirometry, preparation of a written asthma action plan) and patient and general practitioner rating of the acceptability and usefulness of spirometry. Results: There were no statistically significant differences between the groups at 12 months for quality of life (mean difference = -0.23; 95%; CI: -0.44, -0.01), days off work (rate ratio = 1.52; 95% CI: 0.91, 2.54), exacerbations (rate ratio = 1.09; 95% CI: 0.85, 1.41), asthma on waking (rate ratio = 1.21; 95% CI: 0.79, 1.85), nocturnal asthma (rate ratio = 0.98; 95% CI: 0.63, 1.51) and post-bronchodilator FEV. 1/FVC ratio (mean difference = -0.01, 95% CI: -0.03, 0.02). There was no improvement in the quality of care provided. Conclusions: Training in spirometry did not result in any measurable improvement in the use of spirometry, quality of management of asthma or patient outcomes in primary care. Refereed/Peer-reviewed

We have synthesized epitaxial NdNiO$_{3}$ ultra-thin films in a layer-by-layer growth mode under tensile and compressive strain on SrTiO$_{3}$ (001) and LaAlO$_3$ (001), respectively. A combination of X-ray diffraction, temperature dependent resistivity, and soft X-ray absorption spectroscopy has been applied to elucidate electronic and structural properties of the samples. In contrast to the bulk NdNiO$_{3}$, the metal-insulator transition under compressive strain is found to be completely quenched, while the transition remains under the tensile strain albeit modified from the bulk behavior., 4 pages, 4 figures

Epitaxial strain is a proven route to enhancing the properties of complex oxides, however, the details of how the atomic structure accommodates strain are poorly understood due to the difficulty of measuring the oxygen positions in thin films. We present a general methodology for determining the atomic structure of strained oxide films via x-ray diffraction, which we demonstrate using LaNiO3 films. The oxygen octahedral rotations and distortions have been quantified by comparing the intensities of half-order Bragg peaks, arising from the two unit cell periodicity of the octahedral rotations, with the calculated structure factor. Combining ab initio density functional calculations with these experimental results, we determine systematically how strain modifies the atomic structure of this functional oxide., 23 pages, 11 figures

Background Age and life expectancy of residents in many developed countries, including Australia, is increasing. Health resource and medicine use in the very old is not well studied. The purpose of this study was to identify annual use of health services and medicines by very old Australian veterans; those aged 95 to 99 years (near centenarians) and those aged 100 years and over (centenarians). Methods The study population included veterans eligible for all health services subsidised by the Department of Veterans' Affairs (DVA) aged 95 years and over at August 1st 2006. A cohort of veterans aged 65 to 74 years was identified for comparison. Data were sourced from DVA claims databases. We identified all claims between August 1st 2006 and July 31st 2007 for medical consultations, pathology, diagnostic imaging and allied health services, hospital admissions, number of prescriptions and unique medicines. Chi squared tests were used to compare the proportion of centenarians (those aged 100 years and over) and near centenarians (those aged 95 to 99 years) who accessed medicines and health services with the 65 to 74 year age group. For those who accessed health services during follow up, Poisson regression was used to compare differences in the number of times centenarians and near centenarians accessed each health service compared to 65 to 74 year olds. Results A similar proportion (98%) of centenarians and near centenarians compared to those aged 65 to 74 consulted a GP and received prescription medicine during follow up. A lower proportion of centenarians and near centenarians had claims for specialist visits (36% and 57% respectively), hospitalisation (19% and 24%), dental (12% and 18%), physiotherapy (13% and 15%), pathology(68% and 78%) and diagnostic imaging services (51% and 68%) (p < 0.0001) and a higher proportion had claims for care plans (19% and 25%), occupational therapy (15% and 17%) and podiatry services (54% and 58%) (p < 0.0001). Compared to those aged 65 to 74, a lower proportion of centenarians and near centenarians received antihypertensives, lipid lowering therapy, antiinflammatories, and antidepressants (p < 0.0001) and a higher proportion received antibiotics, analgesics, diuretics, laxatives, and anti-anaemics (p < 0.0001). Conclusions Medical consultations and medicines are the health services most frequently accessed by Australian veteran centenarians and near centenarians. For most health services, the proportion of very old people who access them is similar to or less than younger elderly. Our results support the findings of other studies which suggest that longevity is not necessarily associated with excessive health service use.

A video supplement to this article will be available from the Video Journal of Orthopaedics. A video clip will be available at the JBJS web site, www.jbjs.org. Background: There is increased early postoperative mortality after elective joint replacement surgery. However, the magnitude and duration of the increased mortality are uncertain. Methods: Data on total knee and total hip replacement from the comprehensive national registries in Australia and Norway were assessed. Only patients between fifty and eighty years of age with osteoarthritis were included. Overall, the study included 81,856 patients with a total knee replacement and 106,254 patients with a total hip replacement. Smoothed intensity curves were calculated to show the change in mortality for the early postoperative period, whereas the effects of risk factors were studied with use of the nonparametric additive Aalen model. Results: We found that early postoperative mortality was increased for the first twenty-six postoperative days (95% confidence interval, twenty-two to forty-one days). The excess mortality, compared with a baseline mortality (calculated as the average mortality from Day 100 to Day 200), for these twenty-six days was estimated to be 0.12% (95% confidence interval, 0.11% to 0.14%). The most important risk factors for excessive early postoperative mortality were male sex and high age (more than seventy years of age). Conclusions: There is an increased, but low, early postoperative mortality following lower extremity joint replacement surgery. The excess mortality persists, but steadily decreases, for approximately the first twenty-six postoperative days. Refereed/Peer-reviewed

Background: This study assessed whether the number of comorbid conditions unrelated to diabetes was associated with a delay in therapeutic progression of diabetes treatment in Australian veterans. Conclusions/significance: Increasing numbers of unrelated conditions decreased the likelihood of therapeutic progression in veterans with diabetes. These results have implications for the development of quality measures, clinical guidelines and the construction of models of care for management of diabetes in elderly people with comorbidities. Methodology/principal findings: A retrospective cohort study was undertaken using data from the Australian Department of Veterans' Affairs (DVA) claims database between July 2000 and June 2008. The study included new users of metformin or sulfonylurea medicines. The outcome was the time to addition or switch to another antidiabetic treatment. The total number of comorbid conditions unrelated to diabetes was identified using the pharmaceutical-based comorbidity index, Rx-Risk-V. Competing risk regression analyses were conducted, with adjustments for a number of covariates that included age, gender, residential status, use of endocrinology service, number of hospitalisation episodes and adherence to diabetes medicines. Overall, 20134 veterans were included in the study. At one year, 23.5% of patients with diabetes had a second medicine added or had switched to another medicine, with 41.4% progressing by 4 years. The number of unrelated comorbidities was significantly associated with the time to addition of an antidiabetic medicine or switch to insulin (subhazard ratio [SHR] 0.87 [95% CI 0.84-0.91], P

Background and purpose: The Kaplan-Meier (KM) method is often used in the analysis of arthroplasty registry data to estimate the probability of revision after a primary procedure. In the presence of a competing risk such as death, KM is known to overestimate the probability of revision. We investigated the degree to which the risk of revision is overestimated in registry data. Patients and methods: We compared KM estimates of risk of revision with the cumulative incidence function (CIF), which takes account of death as a competing risk. We considered revision by (1) prosthesis type in subjects aged 75-84 years with fractured neck of femur (FNOF), (2) cement use in monoblock prostheses for FNOF, and (3) age group in patients undergoing total hip arthroplasty (THA) for osteoarthritis (OA). Results: In 5,802 subjects aged 75-84 years with a monoblock prosthesis for FNOF, the estimated risk of revision at 5 years was 6.3% by KM and 4.3% by CIF, a relative difference (RD) of 46%. In 9,821 subjects of all ages receiving an Austin Moore (non-cemented) prosthesis for FNOF, the RD at 5 years was 52% and for 3,116 subjects with a Thompson (cemented) prosthesis, the RD was 79%. In 44,365 subjects with a THA for OA who were less than 70 years old, the RD was just 1.4%; for 47,430 subjects > 70 years of age, the RD was 4.6% at 5 years. Interpretation: The Kaplan-Meier method substantially overestimated the risk of revision compared to estimates using competing risk methods when the risk of death was high. The bias increased with time as the incidence of the competing risk of death increased. Registries should adopt methods of analysis appropriate to the nature of their data. Refereed/Peer-reviewed

Purpose We aimed to determine the duration of first episode of therapy and overall therapy as well as time without treatment for bisphosphonates. Methods Data were extracted from Department of Veterans' Affairs (DVA) dataset for those with at least one dispensing for a bisphosphonate between April 2001 and April 2007. Episodes of use were determined as the number of treatment days between the first and last prescription plus 35 days once a dispensing gap of 105 days had been reached, or where no treatment gaps were recorded, the study end date. Kaplan–Meier analyses were undertaken for the first episode of use, overall duration and time without treatment. Results When considering only the duration of first episode, median bisphosphonate use was 1.19 years. The median duration extended to 3.27 years when all episodes of use were considered. Overall, 52.0% of subjects reached at least 3 years of treatment and 66.5% of existing users had a duration of at least 3 years. Median time without treatment was 1.65 years. Overall, 81% of the cohort had enough medicine dispensed to be considered adherent throughout their duration of use. Conclusion Over 50% of subjects and 66% of existing users had duration consistent with the minimum recommended. Adherence within an episode was high. The focus for improving duration of bisphosphonate use should be on reducing the time without treatment, rather than adherence at the time of use. Studies assessing only the first episode of use in new users of medicines may underestimate duration. Copyright © 2008 John Wiley & Sons, Ltd.

Objectives: To investigate the mortality and cancer incidence of Australian nuclear test participants, and to identify any association with exposure to ionising radiation. Methods: A retrospective cohort study was carried out in which the mortality and cancer incidence rates of participants (n = 10 983) were compared with rates in the general male Australian population. Dose reconstructions were carried out by a panel of health physicists. Mortality and cancer rates were compared with the general population and between groups of subjects categorised by assessed radiation exposure. Results: All-cause mortality was not raised. Mortality and incidence were significantly raised for cancers of the head and neck, lung, colon and rectum, and prostate, and for all cancers combined. For oesophageal cancer, melanoma, all leukaemias and non-chronic lymphatic leukaemia (non-CLL leukaemia), incidence was significantly raised, but mortality was non-significantly raised. No association was found between radiation exposure and overall cancer incidence or mortality, or with any cancer or cancer deaths occurring in excess. Conclusions: There is no evidence that the excess cancers and cancer deaths were caused by radiation exposure at the test sites. Possible contributing factors are high smoking prevalence and demographic differences from the Australian population with whom rates were compared. Asbestos is a likely contributor to some cancers in naval personnel.

We report the first observation of `orbital truncation rods' -- the scattering arising from the termination of bulk orbital order at the surface of a crystal. The x-ray measurements, performed on a cleaved, single-layered perovskite, La0.5Sr1.5MnO4, reveal that while the crystallographic surface is atomically smooth, the orbital `surface' is much rougher, with an r.m.s. deviation from the average `surface' of ~0.7nm. The temperature dependence of this scattering shows evidence of a surface-induced second order transition., Comment: 13 pages, 4 figures

In this study of the incidence of asbestos-related cancer in the Australian petroleum industry, the authors traced a cohort of 16,543 petroleum industry workers for a total of 226,989 person-years. There were 18 cases of pleural mesothelioma; 12 occurred in refinery nonoffice workers, for whom the Standardized Incidence Ratio was 3.77 (95% confidence interval = 1.95-6.59). The incidence of lung cancer was significantly lower than that in the general male population. Lung cancer incidence was higher in maintenance workers than in nonmaintenance workers, but the excess was not statistically significant, as it was based on small numbers with wide confidence intervals. Lung cancer rates in refinery workers did not increase with duration of employment; however, they did tend to be higher in workers hired in earlier decades. Excess mesothelioma incidence in refinery workers is confirmed, but it is likely that there are few if any asbestos-related lung cancers.