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The impact of anticoagulant medications on fragility femur fracture care : The Hip and Femoral Fracture Anticoagulation Surgical Timing Evaluation (Haste) Study
Get PDFIntroduction:
Due to their hypocoagulable state on presentation, anticoagulated patients with femoral fragility fractures typically experience delays to surgery. There are no large, multicentre studies previously carried out within the United Kingdom (UK) evaluating the impact of anticoagulant use in this patient population. This study aimed to evaluate the current epidemiology and compare the perioperative management of anticoagulated and non-anticoagulated femoral fragility fracture patients.
Methods:
Data was prospectively collected through a collaborative, multicentre approach involving hospitals across the United Kingdom. Femoral fragility fracture patients aged ≥60 years and admitted to hospital between 1st May to 31st July 2023 were included. Main outcomes under investigation included time to surgery, receipt of blood transfusion between admission and 48 hours following surgery, length of stay, and 30-day mortality. These were assessed using multivariable linear and logistic regression, and Cox proportional hazards models. Only data from hospitals ≥90% case ascertainment with reference to figures from the National Hip Fracture Database (NHFD) were analysed.
Results:
Data on 10,197 patients from 78 hospitals were analysed. 18.5% of patients were taking anticoagulants. Compared to non-anticoagulated patients, time to surgery was longer by 7.59 hours (95%CI 4.83–10.36; p<0.001). 42.41% of anticoagulated patients received surgery within 36 hours (OR 0.54, 95%CI 0.48-0.60, p<0.001). Differences in time to surgery were similar between countries however there was some variation across units. There were no differences in blood transfusion and length of stay between groups (OR 1.03, 95%CI 0.88–1.22, p=0.646 and 0.22 days, 95%CI -4.48–0.887; p=0.887 respectively). Mortality within 30 days of admission was higher in anticoagulated patients (HR 1.27, 95%CI 1.03–1.57, p=0.026).
Conclusions:
Anticoagulated femoral fragility fracture patients comprise a substantial number of patients, and experience relatively longer delays to surgery with less than half receiving surgery within 36 hours of admission. This may have resulted in their comparatively higher mortality rate. Inclusion of anticoagulation status in the minimum data set for the NHFD to enable routine auditing of performance, and development of a national guideline on the management of this growing and emerging patient group is likely to help standardise practice in this area and improve outcomes
Evidence review : Essential capabilities for managing an aged care workforce
Get PDFEffective management and leadership in aged care are essential for effective aged care worker performance, which, in turn, enables high-quality care. This research report commissioned by the Australian Association of Gerontology highlights the critical need to understand better the nature and challenges of aged care management and leadership against a backdrop of growing demand for care and predicted shortfalls in the supply of workers to the sector
'Bengali Cockney, Black Cockney, East End Cockney, Essex Cockney, Jewish Cockney, Sylheti Cockney’ : why community languages matter
No full textIn response to a community petition, Tower Hamlets council in east London has designated Cockney as a “community language”. This recognition paves the way for the borough to actively challenge the linguistic discrimination that speakers of “non-standard” English dialects face
Approval-based committee voting in practice : a case study of (over-)representation in the Polkadot blockchain
No full textWe provide the first large-scale data collection of real-world approval-based committee elections. These elections have been conducted on the Polkadot blockchain as part of their Nominated Proof-of-Stake mechanism and contain around one thousand candidates and tens of thousands of (weighted) voters each. We conduct an in-depth study of application-relevant questions, including a quantitative and qualitative analysis of the outcomes returned by different voting rules. Besides considering proportionality measures that are standard in the multiwinner voting literature, we pay particular attention to less-studied measures of overrepresentation, as these are closely related to the security of the Polkadot network. We also analyze how different design decisions such as the committee size affect the examined measures
Flux-pinning mediated superconducting diode effect in NbSe2/CrGeTe3 heterostructure
Get PDFIn ferromagnet/superconductor bilayer systems, dipolar fields from the ferromagnet can create asymmetric energy barriers for the formation and dynamics of vortices through flux pinning. Conversely, the flux emanating from vortices can pin the domain walls of the ferromagnet, thereby creating asymmetric critical currents. Here, we report the observation of a superconducting diode effect (SDE) in a NbSe2/CrGeTe3 van der Waals heterostructure in which the magnetic domains of CrGeTe3 control the Abrikosov vortex dynamics in NbSe2. In addition to extrinsic vortex pinning mechanisms at the edges of NbSe2, flux-pinning-induced bulk pinning of vortices can alter the critical current. This asymmetry can thus be explained by considering the combined effect of this bulk pinning mechanism along with the vortex tilting induced by the Lorentz force from the transport current in the NbSe2/CrGeTe3 heterostructure. We also provide evidence of critical current modulation by flux pinning depending on the history of the field setting procedure. Our results suggest a method of controlling the efficiency of the SDE in magnetically coupled van der Waals superconductors, where dipolar fields generated by the magnetic layer can be used to modulate the dynamics of the superconducting vortices in the superconductors
Symmetry breaking at a topological phase transition
Get PDFSpontaneous symmetry breaking is a foundational concept in physics. In condensed matter, it characterizes conventional continuous phase transitions but is absent at topological phase transitions such as the Berezinskii–Kosterlitz–Thouless (BKT) transition—as in the BKT case the expected norm (i.e., the magnitude) of the U(1) order parameter vanishes in the thermodynamic limit at all nonzero temperatures. Phenomena consistent with low-temperature broken symmetry have been observed, however, in many different BKT experiments. Examples include recent experiments on superconducting films and the seminal work on two-dimensional arrays of Josephson junctions. While the inaccessibility of the above thermodynamic limit partially explains this paradox in finite systems, the full dynamical framework of symmetry breaking at the BKT transition remains unresolved. Here we provide this by introducing the broader concept of general symmetry breaking. This encompasses both spontaneous symmetry breaking and the BKT case by allowing the expected norm of the order parameter to go to zero in the thermodynamic limit, provided its directional phase fluctuations are asymptotically smaller. We demonstrate this asymptotically slow directional mixing in the low-temperature BKT phase. This explicitly shows that the order parameter arbitrarily chooses some well-defined direction in the thermodynamic limit, predicting negligible phase fluctuations compared to the expected norm in arbitrarily large experimental BKT systems. Our results provide a model for directional mixing timescales across the diverse array of experimental BKT systems. We suggest various experiment
Demand-and-supply imbalance risk and long-term swap spreads
No full textWe develop and test a model in which swap spreads are determined by end users' demand for and constrained intermediaries' supply of long-term interest rate swaps. Swap spreads reflect compensation both for using scarce intermediary capital and for bearing convergence risk—i.e., the risk spreads will widen due to a future demand-and-supply imbalance. We show that a proxy for the intermediated quantity of swaps—dealers' net position in Treasuries—flipped sign during the Global Financial Crisis when swap spreads turned negative and that this variable predicts the excess returns on swap spread trades. Exploiting our model's sign restrictions, we identify shifts in demand and supply and find that both contribute significantly to the volatility of swap spreads
Microcracks in CVD diamond produced by scaife polishing
Get PDFWe investigate sub-surface damage in a CVD diamond, polished on a (110) plane using the traditional scaife method. The damage lies in tracks that consist of microcracks lying perpendicular to the polishing direction. These cracks have an irregular spacing and are comprised mainly of {111} facets. Their geometry is consistent with a modified Hertzian fracture, caused by a stick-slip movement of relatively large (micron-sized) diamond particles on the scaife. The interior surface of the cracks shows a 1x1 CH3 surface reconstruction, consistent with a high hydrogen overpressure that results from ingress of hydrocarbons in the polishing lubricant and a relatively low temperature process. The crack edge is ragged, and voids with sizes of a few nm are found up to hundreds of nm from the crack front, particularly where the crack ends at the polished surface. We propose that these features are evidence of significant healing of the cracks once the applied stress is removed. Luminescence at the crack tips is seen, presumably due to impurities trapped in these voids, which quenches with electron irradiation at 10 keV
Parallel derandomization for coloring
Get PDFGraph coloring problems are among the most fundamental problems in parallel and distributed computing, and have been studied extensively in both settings. In this context, designing efficient deterministic algorithms for these problems has been found particularly challenging.
In this work we consider this challenge, and design a novel framework for derandomizing algorithms for coloring-type problems in the Massively Parallel Computation (MPC) model with sublinear space. We give an application of this framework by showing that a recent (degree+1)-list coloring algorithm by Halldorsson et al. (STOC'22) in the LOCAL model of distributed computation can be translated to the MPC model and efficiently derandomized. Our algorithm runs in O(log log log n) rounds, which matches the complexity of the state of the art algorithm for the (Delta + 1)-coloring problem
Can information about jobs improve the effectiveness of vocational training? Experimental evidence from India
Get PDFWe use a randomized experiment to evaluate the impact of providing richer information about prospective jobs to vocational trainees on their employment outcomes. The setting of the study is the vocational training program DDU-GKY in India. We find that including in the training two information sessions about placement opportunities make trainees 18% more likely to stay in the jobs in which they are placed. We provide suggestive evidence that the effect is driven by improved selection into training: as a result of the intervention, trainees that are over-optimistic about placement jobs are more likely to drop out before placement