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Short term-outcomes of periacetabular osteotomy in the neuromuscular hip
Get PDFThe study aims to evaluate our experience of the Bernese periacetabular osteotomy (PAO) in patients with neurogenic hip dysplasia. Retrospective data were collected for patients with neurogenic hip dysplasia, managed with PAO over a 10-year period. Data were collected for 20 consecutive patients (23 hips). Mean age at the time of surgery was 15 years (range 12–31). 85% had a diagnosis of cerebral palsy (GMFCS 1(18%), 2(18%), 3(35%), 4(12%), 5(18%)). Mean follow up was 47 months. Electronic records were reviewed for outcomes. Pre- and post-operative radiographs were evaluated separately by two independent assessors using TraumaCad software. Post-operative radiographic evaluation was available for 20 patients (21 hips). The median lateral centre edge angle was corrected from −1° pre-operatively (range: −58° to 25°) to 42° post operatively (range: 15° to 65°). Tönnis angle was corrected from an average of 26° pre-operatively (range: 10° to 37°) to 9° post-operatively (range: −19 to 29). Reimer’s index decreased from an average of 50% (range: 27% to 93%) to 7% (range 0% to 25%) post-operatively. At the latest follow there was absence of pain in 16 patients. Our experience has demonstrated safe use of the PAO, in conjunction with soft tissue procedures and femoral osteotomy, in the management of neuromuscular patients. In this cohort there was stable reduction of the hip in all but two patients (three hips), and effective pain management for this challenging patient group
Reappraising the Gandhāra still: implications for understanding early distillation technology through experimentation and experimental reconstruction
Get PDFThe use of experimentation within studies of early distillation technology has largely taken a methodological approach which aims to demonstrate how suggested technical evolutions and apparatus configurations operate. This paper examines the viability of the ‘Gandhāra still’ reconstruction for distillation within a unified campaign of comparative and exploratory experimentation, acting as a framework for critical evaluation. First generated from interpretations on the function of predominately 2nd c. BCE– 4th c. CE ceramic vessels found across South-Central Asia, the Gandhāra still has been a central component in the conceptualisation of an “ancient Indian distillation hypothesis” that has received considerable attention in the historiography of science. This uptake in interest has led to researchers from a variety of disciplinary backgrounds to reinforce the still’s existence and distilling capacity, including through the use of experimentation. In response, this paper details a new campaign of experimental trials which identified functional reasons as to why the apparatus does not operate. Crucially, trials demonstrated how the interpreted set of apparatus components together cannot sufficiently condense produced distilling vapour due to their morphology. In tandem, the campaign revealed practical issues associated with internal reflux actions and pressurisation in the still that had not been identified previously. Further analysing such a pervasive dialogue on technical innovation invites wider re-evaluations of distillation technology chartings and introduces a nuanced suite of considerations in discussing the inception of early distillation
Enhanced electrocaloric effect in lead-free relaxor ferroelectrics via point defect engineering
Get PDFThe electrocaloric effect enables solid-state refrigeration technology with high energy efficiency and zero global warming potential. Normal displacive ferroelectric materials exhibit the highest electrocaloric effect just above their Curie point. The freezing temperature (Tf) of a relaxor ferroelectric material functions as a Curie point in displacive ferroelectrics, suggesting that the highest electrocaloric effect for a relaxor ferroelectric material is near its Tf. However, relaxor ferroelectrics often exhibit significant hysteresis around Tf, making them unsuitable for electrocaloric applications. In this work, we show that the highest electrocaloric effect in lead-free Bi0.5Na0.5TiO3-SrTiO3-based relaxor ferroelectric ceramics occurs at temperatures a few degrees above the temperature with their maximum permittivity (Tm) and is far above their Tf. Moreover, the A-site vacancy design can be used to effectively increase the electrocaloric effect and broaden the working temperature range, which is due to the increase in field-induced polarization and strong relaxation achieved via point defect engineering. This Letter reveals the appropriate temperature window for the high electrocaloric effect in relaxor ferroelectrics and shows that the A-site vacancy design can further enhance electrocaloric properties and extend the working temperature range for electrocaloric applications
Estimating the Causal Effect of Realistic Treatment Strategies Using Longitudinal Observational Data
No full textStructural unification of diverse transmembrane acyltransferases reveals a conserved fold for the Transmembrane Acyl Transferase (TmAT) superfamily
Get PDFThe movement of acyl groups across biological membranes is essential for many cellular processes. One major family of proteins catalysing this reaction are the acyl transferase family 3 (AT3) proteins, which form a pore to allow acyl-CoA to penetrate the membrane for transfer onto an extracytosolic acceptor molecule. Recent structures of the sequence-unrelated human heparan-α-glucosaminide N-acetyltransferase (HGSNAT) support a similar transmembrane acyl-group transfer mechanism. Here we demonstrate that both protein families contain a conserved 10-transmembrane helical fold with high structural and detectable sequence conservation around the acyl-CoA pore, supporting the previously proposed Transmembrane Acyl Transferase (TmAT) protein superfamily. In addition, we identify TmAT proteins, including the human Golgi sialate-O-acetyltransferase (CASD1), the human/fungal PIG-W/GWT1 enzymes and the bacterial vancomycin resistance protein VanTG, where the TmAT domain's function has been largely unrecognised. We conclude that the TmAT fold represents an ancient architecture for transmembrane acyl-group transfer with important roles in the dynamic modification of glycans in diverse processes across the three domains of life
Effects of Perceived Scarcity on Mental Health, Time and Risk Preferences, and Decision-Making During and After COVID-19 Lockdown: A Quasi-Natural Experimental Study (Preprint)
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Sound field characteristics and influencing factors of traditional Chinese interlocked timber-arched covered bridges
Get PDFAs an important type of traditional architecture in China, Chinese interlocked timber-arched covered (CITAC) bridges provide transportation functions, while interior spaces are also utilized for ritual activities. The unique spatial form of the CITAC bridge considerably influences the internal sound field. In this study, field measurements and acoustic simulations were conducted to determine the sound field characteristics of CITAC bridges and analyze the influencing factors. The results indicate that the mid-frequency reverberation time (RT30M) of the four measured CITAC bridges ranged between 0.37 and 0.50 s. The spatial dimensions, enclosure structure systems, and occupancy of the CITAC bridges all influenced their sound fields: increasing the bridge length or adding gable walls on both sides significantly increased RT30M; as the opening angle of the protective wooden panels beneath the eaves increased by 15°, the mid-frequency early decay time (EDTM) inside the CITAC bridge decreased by approximately 10%. EDTM and RT30M were approximately 20% lower in the occupied condition than in the unoccupied condition. In addition to the cross-sectional aspect ratio, the influences of other spatial elements on the sound fields of CITAC bridges align with previous studies on the sound field characteristics of long spaces
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