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The article investigates buckling cases in Great Britain where buckling length does not meet the standard specified in the British Standard (BS) 5400: part 3. Based on the BS 5400: part 3, calculation of buckling resistance for the construction should be lengthy and conservative to extract greater resistance from beams. The author concluded that curves in BD 13/06 and BS 5400 should be revised to remove curves below the standard.

This paper presents an extensive parametric study of elastic and inelastic buckling of cellular beams subjected to strong axis bending in order to investigate the effect of a variety of geometric parameters, and further generate mass data to validate and train a neural network-based formula. Python was employed to automate mass finite element (FE) analyses and reliably examine the influence of the parameters. Overall, 102,060 FE analyses were performed. The effects of the initial geometric imperfection, material nonlinearity, manufacture-introduced residual stresses, web opening diameter, web-post width, web height, flange width, web and flange thickness, end web-post width, and span of the beams and their combinations were thoroughly examined. The results are also compared with the current state-of-the-art design guidelines used in the UK. It was concluded that the critical elastic buckling load of perforated beams corresponds to the lateral movement of the compression flange while the most critical parameters are the web thickness and the geometry of the flange. However, from the inelastic analysis, the geometry and position of the web opening influence the collapse load capacity in a similar fashion to the geometry of the flange and thickness of the web. It was also concluded that the effect of the initial conditions was insignificant. • Mass (102,060) FE analyses were conducted and compared with SCI's analytical method. • The most critical parameter for both global elastic and inelastic analyses is the web thickness. • Perforated beams with non-standard web opening configurations should be considered for Eurocode 3 compliance. • Mass data results can be used to derive sophisticated closed-form solutions. • The effect of the initial geometric and material imperfection was found insignificant. [ABSTRACT FROM AUTHOR]

Developers of new finite elements or nonlinear solution techniques rely on discriminative benchmark tests drawn from the literature to assess the advantages and drawbacks of new formulations. Buckling benchmark tests provide a rigorous evaluation of finite elements applied to thin structures, and a complete and detailed set of reference results would therefore prove very useful in carrying out such evaluations. Results are usually presented in the form of load-deflection curves that developers must reconstruct by extracting the points, a procedure which is often tedious and inaccurate. Moreover the curves are usually given without accompanying information such as the calculation time or number of iterations it took for the model to converge, even though this type of data is equally important in practice. This paper presents ten different limit-point buckling benchmark tests, and provides for each one the reference load-deflection curve, all the points necessary to recreate the curve in tabulated form, analysis data such as calculation time, number of iterations and increments, and all of the inputs used to obtain these results. [ABSTRACT FROM AUTHOR]

Extreme high temperatures are associated with increased incidences of rail buckles. Climate change is predicted to alter the temperature profile in the United Kingdom with extreme high temperatures becoming an increasingly frequent occurrence. The result is that the number of buckles, and therefore delays, expected peryear will increase if the track is maintained to the current standard. This paper uses a combination of analogue techniques and a weather generator to quantify the increase in the number of buckles and rail related delays in the southeast of the United Kingdom. The paper concludes by assigning a cost to the resultant rise in delays and damage before making recommendations on how these effects can be mitigated. Copyright © 2008 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

Introduction: To identify variables associated with primary anatomical outcome following vitrectomy and internal tamponade for rhegmatogenous retinal detachment (RD)., Methods: A retrospective analysis of prospectively collected data, using a database of RD treated with vitrectomy and internal tamponade. Collected data complied with the RCOphth Retinal Detachment Dataset. The main outcome measure was anatomical failure within six months of surgery., Results: There were 6377 vitrectomies. 869 eyes were excluded, either because no outcome was recorded, or inadequate follow up, leaving 5508 operations for analysis. 63.9% of patients were male, and the median age was 62. Primary anatomical failure occurred in 13.9%. On multivariate analysis, the following were associated with increased risk of failure: age <45, or >79, inferior retinal breaks, total detachment, one quadrant or greater inferior detachment, low density silicone oil, and presence of proliferative vitreoretinopathy. C 2 F 6 tamponade, cryotherapy, and 25 G vitrectomy, were associated with reduced risk of failure. The area under the receiver operator curve was 71.7%. According to this model, 54.3% of RD are at low risk (<10%), 35.6% are at moderate risk (10-25%), and 10.1% are at high risk (>25%) of failure., Conclusions: Previous attempts to identify high risk RD have been limited by small numbers, the inclusion of both scleral buckling and vitrectomy, or by excluding some types of RD. This study examined outcomes in unselected RD, treated by vitrectomy. Identification of the variables associated with anatomical outcome after RD surgery enables accurate risk stratification, which is valuable for patient counselling and selection, and for future clinical trials., (© 2023. The Author(s).)

Background: There are 16 vitreoretinal (VR) fellowships listed on the British and Eire Association of Vitreoretinal Surgeons (BEAVRS) website offering places to 23 applicants, however, this list is not exhaustive. The purpose of this survey was to evaluate surgical volume, training, and experience of VR fellows in the UK., Methods: An anonymous survey was disseminated online to current and past VR fellows who are members of BEAVRS. Participants were asked about their surgical experience and confidence, before and during their fellowship, in performing a variety of procedures. Participants were also asked about their academic achievements and their career prospects., Results: All 26 respondents felt that their fellowship met their surgical needs and would recommend it to others. Upon completion, 92% felt prepared to work as a consultant. Following fellowship completion, the median (IQR) number of procedures performed were: phacoemulsification: 91 (51-131), pars-plana vitrectomy (PPV): 351 (226-451), simple-retinal detachment (RD): 176 (126-226), complex-RD: 31 (16-51), scleral buckle (SB): 16 (80-26), membrane-peels: 76 (41-88), intraocular-foreign body (IOFB) removal: 3 (3-3), indirect laser: 51 (11-91), scleral-fixated intraocular-lens (sfIOL): 3 (3-8), removal-of-dropped-nucleus (RODN): 16 (8-26), diabetic membrane delaminations: 16 (8-16); with an increase of confidence in performing all VR procedures (p < 0.001). Participants completed 2 (1-2) presentations and 2 (0-3) papers with no difference in academic performance between those with/without postgraduate qualifications (p = 0.409)., Conclusions: Overall, fellowships in the UK are of a high quality and prepare the fellow adequately for progression into a consultant post. They help increase surgical confidence and provide opportunities to complete academic work. Fellowships without VR on-call commitments can be improved by incorporating on-call duties. Finally, COVID-19 impacted exposure to elective cases., (© 2022. The Author(s), under exclusive licence to The Royal College of Ophthalmologists.)

Recent reports suggest that the use of an outpatient-based procedure (pneumatic retinopexy, PR) for retinal detachment repair should be encouraged within the UK, especially in light of Covid-19 and possible restrictions/competing demands on access to operating theatres. It is therefore essential that patients receive comprehensive information about the risks and benefits of this approach compared with a formal surgical repair either by pars plana vitrectomy (PPV) and/or scleral buckling (SB). We report a retrospective case series of retinal detachments (RD) satisfying the strict selection criteria for PR but who were managed with formal surgery. Single-operation success rate for PPV/SB at six months follow-up was 93.8% in our study, higher than published primary success rates for PR (60–80%). When counselling patients for possible PR, the ease, speed and potentially reduced co-morbidity of an outpatient-based procedure needs to be balanced against its significantly higher failure rate in comparison with primary PPV/SB. [ABSTRACT FROM AUTHOR]

Objective: To identify risk factors affecting visual outcomes in successfully re-attached macula-off rhegmatogenous retinal detachment (RD) surgery., Design: A prospective study, using online databases, of visual outcomes for 2074 macula-off retinal detachments that were successfully re-attached by vitrectomy and internal tamponade. The database included detailed retinal diagrams of each detachment., Main Outcome Measure: The probability of achieving a post-operative visual acuity (VA) of ≤0.30 LogMAR (Snellen 6/12 or better)., Results: Male patients accounted for 64.9% of the sample and the median age was 63 years old. The median pre-operative VA was counting fingers (LogMAR 1.98); this improved to 0.41 LogMAR post-operatively. A post-operative VA of ≤0.30 LogMAR was achieved for 1012 (48.8%) eyes and the factors affecting this were the patient age and gender, pre-operative VA, duration of central vision loss, PVR grade, lens status, total RD and the presence of any ocular co-pathology where the model area under the receiver operator curve was 71.6%., Conclusions: From the identified risk factors that decrease the probability of achieving a post-operative visual acuity of ≤0.30 LogMAR, the most important modifiable risk factor was the duration of central vision loss. Recent macula-off retinal detachments should be repaired within 72 h of the loss of central vision.

Great Britain's main line railway network is known to experience various temperature-related impacts, e.g. track buckling and overhead power line sag at high ambient temperatures. Climate change could alter the frequency of occurrence of these impacts. We have therefore investigated the climate change impact on various temperature-related issues, identified during workshops with rail industry specialists, using a perturbed physics ensemble (PPE) of the Met Office's regional climate model (RCM), HadRM3. We have developed novel approaches to combine RCM data with railway industry knowledge, typically by identifying key meteorological thresholds of interest and analysing exceedance of these out to the 2040s. We performed a statistical analysis of the projected changes for each issue, via bootstrapping of the unperturbed PPE member. Although neither the PPE nor the bootstrapping analysis samples the full range of uncertainty in the projections, they nonetheless provide complementary perspectives on the suitability of the projections for use in decision-making. Our main findings include projected increases in the summertime occurrence of temperature conditions associated with (i) track buckling, (ii) overhead power line sag, (iii) exposure of outdoor workers to heat stress, and (iv) heat-related delays to track maintenance; and (v) projected decreases in the wintertime occurrence of temperatures conditions associated with freight train failure owing to brake problems. For (i), the statistical significance varied with track condition and location; for (ii) and (iii), with location; and for (iv) and (v), projected changes were significant across Great Britain. As well as assessing the changes in climate-related hazard, information about the vulnerability of the network to past temperature-related incidents has been summarised. Combining the hazard and vulnerability elements will eventually support a climate risk assessment for the industry. [ABSTRACT FROM AUTHOR]

Climate change predictions suggest a trend towards hotter drier summers in the UK. At extreme high temperatures the railway network is prone to dangerous, damaging, and expensive rail buckles. In order to reduce the risk of a rail buckle, emergency speed restrictions are introduced which can be costly. This article presents a quantification of the effects of higher summer temperatures due to climate change on the UK railway network. A combination of analogue techniques and a weather generator are used to establish trends between heat-related delays and temperatures. Costs are assigned to the change in frequency and severity of delays and evidence-based recommendations are made for future operations. The results demonstrate that the costs incurred as a result of the hot summer of 2003 will become typical in the 2050s (high emissions scenario) and 2080s (low emissions scenario). If no changes are made to maintenance regimes, it is estimated that the total costs of heat-related delays will eventually double to nearly £23 M during extreme summers. [ABSTRACT FROM AUTHOR]

The article discusses a report from the Royal College of Nursing (RCN) concerning the critical shortage of staff in the emergency departments (EDs) of England to cope with budgetary constraints and rising admissions during the winter season.

Summary: Soil biomes are vast, exceptionally diverse and crucial to the health of ecosystems and societies. Soils also contain an appreciable, but understudied, diversity of opportunistic human pathogens. With climate change and other forms of environmental degradation potentially increasing exposure risks to soilborne pathogens, it is necessary to gain a better understanding of their ecological drivers. Here we use the Galleria mellonella insect virulence model to selectively isolate pathogenic bacteria from soils in Cornwall (UK). We find a high prevalence of pathogenic soil bacteria with two genera, Providencia and Serratia, being especially common. Providencia alcalifaciens, P. rustigianii, Serratia liquefaciens and S. plymuthica strains were studied in more detail using phenotypic virulence and antibiotic resistance assays and whole‐genome sequencing. Both genera displayed low levels of antibiotic resistance and antibiotic resistance gene carriage. However, Serratia isolates were found to carry the recently characterized metallo‐β‐lactamase blaSPR‐1 that, although not conferring high levels of resistance in these strains, poses a potential risk of horizontal transfer to other pathogens where it could be fully functional. The Galleria assay can be a useful approach to uncover the distribution and identity of pathogenic bacteria in the environment, as well as uncover resistance genes with an environmental origin. [ABSTRACT FROM AUTHOR]

The UK's design documents for assessment of steel and composite highway bridges and structures have been updated in line with Highways England's overall plan for modernising the Design Manual for Roads and Bridges. This paper describes the key changes that have been made to the document and their impact on users, providing reassurance that, despite the new format, the methods and requirements are largely unchanged, or changed to facilitate future assessments by allowing more general approaches to be adopted. For steel bridges the key changes are described that affect robustness assessment, notch toughness, bearing stiffeners, cross-girders, stiffened panel buckling and inspection criteria for existing welds. For composite bridges, the changes relate mainly to the serviceability limit state verifications, to fatigue and to the shear connection, as well as the general improvements to remove outdated content and simplify the document. The changes for both documents include greater references to the Eurocodes in general, which will facilitate an easier transition to Eurocode assessment standards when these are published in the future. [ABSTRACT FROM AUTHOR]

This paper is part of a larger project that considers the design of large steel‐framed warehouses and distribution centres ('Big Sheds') in the context of the SCOSS Alert "Effects of Scale" [1]. These buildings are currently designed to Standards and design procedures that were intended for much smaller structures, and are now long out of date. In the UK, the steel frames of such buildings are generally designed on the basis of plastic theory [2], the fundamental research initiated at the University of Cambridge being continued under Horne at the University of Manchester and culminating in the publication in 1981 of Horne and Morris [3]. Since that date, design procedures have largely stood still while Big Sheds have increased enormously in both scale and complexity. In the UK, plastic design is still largely used; while the early design procedures have been automated so that the entire calculation can be dedicated to a computer. Nevertheless, the fundamental plastic design procedures have changed little. In this context, which is continuing to evolve, this paper returns to the fundamentals and questions some of the basic premises. Current design procedures, based on laboratory tests on small stocky sections, can only be extrapolated to the contemporary situation with the aid of advanced numerical modelling and this process has only just begun. Even at this early stage of the research, it is suggested that the use of plastic theory for the design of large structures typified by Big Sheds needs serious reconsideration. [ABSTRACT FROM AUTHOR]

The UK is experiencing unprecedented housing demand, with traditional provision in suburbanised clusters now known to have negative environmental, economic and social impacts. An alternative to this is residential densification through vertical extension; generating a more sustainable urban form whilst also serving to increase circularity of material flows within the construction industry and reduce whole‐life carbon and energy requirements. As a result of their relative abundance, inherent durability, and ease of adaptation, multi storey steel framed buildings are particularly pertinent in this context. It is also likely that sufficient reserve structural capacity exists within this typology; resulting from overdesign, the employment of simplified analytic design methods, and the limited number of section sizes available for use. The relative portion of reserve buckling capacity originating from these sources is assessed using a modified version of the effective length method to account for column continuity in multi‐storey steel frames. This reveals the consideration of column continuity to contribute an average of 1.23 kN/m2 of reserve buckling capacity across typical office buildings, with the amount resulting from section size limitations varying with design scenario. [ABSTRACT FROM AUTHOR]

Summary: In exploring relationships between vitamin D status in childhood and cortical bone, little relationship was observed with plasma concentrations of 25-hydroxyvitamin-D [25(OH)D], whereas 25-hydroxyvitamin-D [25(OH)D] was positively related to cortical bone mineral content (BMC) and cortical thickness, suggesting D exerts a beneficial effect on cortical bone development in contrast to D. Introduction: The study is aimed to determine whether vitamin D status in childhood is related to cortical bone development by examining prospective relationships between plasma concentrations of 25(OH)D and 25(OH)D at 7.6, 9.9 or 11.8 years and peripheral quantitative computed tomography (pQCT) measurements of the mid-tibia at age 15.5 years, in children from the Avon Longitudinal Study of Parents and Children. Methods: Relationships between vitamin D status and pQCT outcomes were analysed by bootstrap linear regression, adjusted for age, sex, body composition, socioeconomic position and physical activity, in 2,247 subjects in whom all covariates were available. 25(OH)D was also adjusted for season and 25(OH)D, and 25(OH)D for 25(OH)D. Results: 25(OH)D was positively related to BMC [0.066(0.009,0.122), P = 0.02], whereas no association was seen with 25(OH)D [−0.008(−0.044,0.027), P = 0.7] [beta (with 95% CI) represents SD changes per doubling of vitamin D], P = 0.03 for difference in associations of 25(OH)D and 25(OH)D with BMC. There were also differences in associations with cortical geometry, since 25(OH)D was positively related to cortical thickness [0.11(0.04, 0.19), P = 0.002], whereas no association was seen with 25(OH)D [−0.04(−0.08,0.009), P = 0.1], P = 0.0005 for difference. These relationships translated into differences in biomechanical strength as reflected by buckling ratio, which was positively related to 25(OH)D [0.06(0.01,0.11), P = 0.02] indicating less resistance to buckling, but inversely related to 25(OH)D [−0.1(−0.19,-0.02), P = 0.03], P = 0.001 for difference. Conclusions: In contrast to 25(OH)D, 25(OH)D was positively related to subsequent cortical bone mass and predicted strength. In vitamin D-deficient children in whom supplementation is being considered, our results suggest that D should be used in preference to D. [ABSTRACT FROM AUTHOR]

Objective: The goal of this work is to describe the first experience in the UK with the slim pre-curved perimodiolar electrode Nucleus CI532 in a continuous series of patients in terms of surgical and clinical reliability and early performance outcomes.Method: In this retrospective review we describe the complication rate (including electrode array tip fold-over), NRT thresholds, hearing preservation, power efficiency and CI performance outcomes in a continuous series of 40 cochlear implants CI532 performed between October 2016 and November 2017 in 17 adults and 13 children with severe to profound hearing loss.Results: Preliminary data from these groups reveals some low-frequency hearing preservation in the CI532 group although none of the patients were conventional hearing preservation candidates. NRT thresholds, power efficiency, and BKB sentences in quiet were measured at 3 and 6 months post activation. There were no significant differences in these results. The average BKB score in quiet increases from 22% pre-operatively to 58% at 3 months and 70% at 6 months. In addition, although hearing preservation was not an objective, low-frequency thresholds were preserved in 20% of cases at 3 and 6 months post-operatively. Complications were observed in 5 cases, one case with non-device related aerocoele and four related to the device array: two cases of tip roll over, one case of the electrode array being placed extra-cochlea, and one case with the electrode buckling into the middle ear. The last 2 cases were dealt with per-operatively.Discussion: Our preliminary results with the CI532 implant indicate that it may be reliably placed with standard surgical techniques but care is needed during the deployment of the electrode. Further initial data suggest that switch on and early electrophysiological measures are comparable to the existing CI 512 device. However whilst preliminary, our data suggest that it may be possible to use this electrode for hearing preservation. However, further studies are required to determine its definitive advantage over other electrode designs.Conclusion: CI532 is a reliable device offering good initial results and could be an option for hearing preservation although further studies are required. [ABSTRACT FROM AUTHOR]

The wind energy sector faces a persistent challenge in developing sustainable solutions for decommissioned Wind Turbine Blades (WTB). This study utilises Lifecycle Assessment (LCA) to evaluate the gate-to-gate carbon footprint of high-profile disposal and recycling methods, aiming to determine optimal strategies for WTB waste treatment in the UK. While this article analyses the UK as a case study, the findings are applicable to, and intended to inform, recycling strategies for WTB waste globally. Long-term sustainability depends heavily on factors like evolving energy grids and changing WTB waste compositions and these must be considered for robust analysis and development strategy recommendations. In the short to medium term, mechanical recycling of mixed WTB waste is sufficient to minimise Global Warming Potential (GWP) due to the scarcity of carbon fibre in WTB waste streams. Beyond 2040, carbon fibre recycling becomes crucial to reduce GWP. The study emphasises the importance of matching WTB sub-structure material compositions with preferred waste treatment options for the lowest overall impact. Future development should focus on the extraction of carbon fibre reinforced polymer (CFRP) structures in WTB waste streams, commercialising large-scale CFRP structure recycling technologies, establishing supply chains, and validating market routes for secondary carbon fibre products. In parallel, scaling up low-impact options, like mechanical recycling, is vital to minimise WTB waste landfilling. Developing viable applications and cost-effective market routes for mechanical recyclates is necessary to displace virgin glass fibres, while optimising upstream recycling processes based on product requirements. [ABSTRACT FROM AUTHOR]

The first microbial culture collection was established in 1890, and subsequently, over the course of the twentieth century, the number of culture collections grew substantially. One such collection was the CABI-IMI Genetic Resources Collection, informally initiated at the origins of the Commonwealth Mycological Institute in 1920 and established as a UK National Collection in 1947. Its holdings reflect the activities of CABI in agriculture and the environment. Like many collections, it was originally established as a taxonomic reference resource. Over the years, deposits have included strains isolated from disease outbreaks in major crops from all parts of the world. Recent developments in genome sequencing technology and bioinformatic analysis have opened up the potential to characterise historic strains to shed more insights on their biology and evolution. In this paper we describe how the resources held within the CABI-IMI culture collection have helped track the emergence and divergence of Fusarium xylarioides, the coffee wilt pathogen, with a specific focus on the evolution of pathogenicity. Such studies illustrate the value held within the world's culture collections—their importance in underpinning science and developing our understanding and evolution of plant diseases as well as how the impact of disease can be mitigated in response to climate change, in order to increase yields and feed the world's burgeoning population. [ABSTRACT FROM AUTHOR]

This paper proposes a methodology to estimate the probability of basic causes of allision accidents between vessels and offshore platforms that overcomes the problem of data scarcity required for causal analysis. The approach uses information derived from incidental data and expert elicitation, processed by a multiple attribute utility method and hierarchical Bayesian analysis. First, the methodology is detailed, briefly describing the adopted approaches. A dataset of allision incidents provided mainly by the UK Health and Safety Executive and other agencies is prepared. The features of the incidents' causation in terms of the causal factors and basic causes are presented and discussed. A novel scheme is proposed to evaluate the annual occurrence rates of basic causes of accidents from the relative importance of each basic cause derived by the Deck of Cards method. Then, a hierarchical Bayesian analysis is conducted to predict the posterior distribution of the occurrence rate of each basic cause in the time frame under analysis. The proposed holistic methodology provides transparent estimates of allision causation probabilities from limited and heterogeneous datasets. [ABSTRACT FROM AUTHOR]

Saleyard Bridge carries the A465 Heads of the Valleys Road over the River Clydach near Gilwern, Monmouthshire, UK. It comprises a 67 m single-span steel–concrete composite multi-girder superstructure made integral with the abutments. A full-depth precast deck was chosen to tackle site constraints and improve constructability. The alternative precast panel connection detail developed used straight laps to overcome the problems that can arise from using typical U-bar loop type connections between precast deck panels. The successful use of the precast panels proved that a deck design with straight laps was a practical alternative. The ability to increase the multi-beam centres and avoid cantilever edge formwork created a more economical solution with savings estimated at £500 000. The paper examines the detailed design and construction planning needed to realise the savings and speed up construction as well as improving site safety. The lessons learnt are also applicable to the wider use of precast panels as an alternative to in situ concreting. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance poses one of the greatest threats to global health and there is an urgent need for new therapeutic options. Phages are viruses that infect and kill bacteria and phage therapy could provide a valuable tool for the treatment of multidrug-resistant infections. In this study, water samples collected by citizen scientists as part of the Citizen Phage Library (CPL) project, and wastewater samples from the Environment Agency yielded phages with activity against clinical strains Klebsiella pneumoniae BPRG1484 and Enterobacter cloacae BPRG1482. A total of 169 and 163 phages were found for K. pneumoniae and E. cloacae, respectively, within four days of receiving the strains. A third strain (Escherichia coli BPRG1486) demonstrated cross-reactivity with 42 E. coli phages already held in the CPL collection. Seed lots were prepared for four K. pneumoniae phages and a cocktail combining these phages was found to reduce melanisation in a Galleria mellonella infection model. The resources and protocols utilised by the Citizen Phage Library enabled the rapid isolation and characterisation of phages targeted against multiple strains. In the future, within a clearly defined regulatory framework, phage therapy could be made available on a named-patient basis within the UK. [ABSTRACT FROM AUTHOR]

Ocular motility disturbances following retinal detachment surgery are well documented, resulting in ocular misalignment and disabling diplopia. Interestingly, there has been a downward trend over the last decade across the United Kingdom with the evolution of refined vitrectomy techniques and instrumentation. We aim to report our updated experience on factors influencing botulinum toxin outcomes in view of the trend toward vitrectomy. The Moorfields strabismus service carried out a follow-up retrospective study of all subjects that received botulinum toxin for retinal surgery-related strabismus at our center over an eleven-year period. All new onset constant or intermittent strabismus following retinal detachment surgery were included. Botulinum toxin response was stratified to good and poor. 32 patients fulfilled our criteria, with a mean follow-up of 20 months. The majority were vitrectomised eyes (62%), presented with diplopia (60%) and exotropia (66%). All isolated and combined vertical deviations (18%) were noted among cryobuckled eyes only. Baseline largest mean horizontal deviation was 49 and 51 prism diopters (PD) among the good and poor responders, respectively. A statistically and clinically significant reduction in the horizontal angle of deviation was noted among the good (p <.0001) responders, requiring a mean of six injections, in comparison to the poor responders (p =.03). Of the good responders, five patients (16%) with decompensated phorias regained fusion control. A small number of complications (15%) were noted, the most marked being intractable diplopia in a good responder (3%) with failure to fuse. Botulinum toxin is a useful treatment modality, particularly when surgical options are limited. It can restore binocularity in patients with preexisting fusion potential. Ocular cosmesis can be achieved but requires ongoing injections. Barriers to fusion restoration include multiple retinal surgeries, persistent macula pathology and central-peripheral retinal rivalry. This highlights the need for rigorous baseline macula assessment to allow a tailored approach when considering botulinum toxin therapy for strabismus. [ABSTRACT FROM AUTHOR]

Despite recent advances in additive manufacturing technologies, challenges remain to build 3D-printed structures at the architectural scale due to the high cost of large printing equipment. To address this challenge, modular construction has demonstrated its merit by making smaller prefabricated components and using on-site assembly. This paper presents a case study of a 3D-printed hypar shell structural art using modular construction. Guided by parametric design and structural analysis, we optimized the hypar shell to form a butterfly-like shape with a hollow-out pattern. The prefabrication of modular units was completed using commercial 3D printers to catch a limited production time. The prefabricated modular unit of the hypar shell was assembled on site for the Guangzhou International Light Festival, in which the lighting effect was added through the adjustable transparency of hollow spaces within the sandwiched panels. The 3D-printed hypar shell was also disassembled and rebuilt in the UK, showcasing the adaptability and flexibility of the modular design. The resulting 3D-printed structural art not only provides unique aesthetics for the built environment but also demonstrates the possibility of building large shell structures with a low budget by reducing complex falsework. [ABSTRACT FROM AUTHOR]

A finite-element method (FEM) model was used to numerically investigate the overall buckling behaviours of hot-rolled (HR), submerged arc welded (SAW) and high-frequency welded (HFW) steel circular columns under axial compression. A three-dimensional FEM model of circular hollow sections was developed by using shell elements considering material non-linearities, geometric imperfections and residual stress. The FEM model was used to simulate experimental studies carried out by past researchers. Good agreement was found between the numerical and experimental results, which validate the FEM model for further research. The validated FEM model was used to analyse 180 numerically generated HR, SAW and HFW steel circular columns with various section sizes and slenderness values. The numerical results were then compared with existing column design curves in Chinese, European and American codes. To further improve the design efficiency, new column design curves for steel circular columns are recommended based on the formulas given in GB 50017-2003 and Eurocode 3. [ABSTRACT FROM AUTHOR]

The use of Eurocodes on real projects in the UK highways sector is nearing reality. National Annexes for all the parts required for bridge design are nearing completion and should be ready by the end of 2007. The Highways Agency and British Standards Institution (BSI) committees are completing production of BSI Published Documents to give non-contradictory complementary information to help with the use of the Eurocodes and a variety of organisations are producing design guides. Despite the cultural and technical changes that the Eurocodes bring, pilot studies have shown that designers adapt remarkably quickly. There are also incentives to embrace the Eurocodes. The less prescriptive approach and more up-to-date rules provide the user with greater scope for innovation and economy. This paper identifies the various areas in steel and concrete design where there are technical differences between the new Eurocodes and BS 5400 and also where the new rules lead to the potential for greater structural economy. [ABSTRACT FROM AUTHOR]

Zymoseptoria tritici is the causal fungus of Septoria tritici blotch (STB), a globally important foliar disease of wheat. Infections by more than one strain of a pathogen, or co‐infections, are known to be the most prevalent form of infection in the field. The impact that co‐infection of Z. tritici has on disease severity for the plant host and its effect on plant defence are not fully understood. Here, isolates of Z. tritici were extracted from STB‐presenting leaves from UK sites. Disease assays comparing single‐isolate inocula to mixed inocula were carried out on three cultivars of wheat, Flame, Stigg and Longbow. Leaves infected with mixed inocula were found to show low disease symptoms, including lesion and pycnidial coverage, compared with those infected with single isolates. Growing mixed isolates together in liquid media did not reveal evidence of competition or decreased growth compared with single‐isolate inocula. Wheat infected with a mixture of at least two Z. tritici isolates (of differing aggressiveness) could induce Pr‐1 (Pathogenesis‐related 1) at a significantly higher level in distal uninfected leaves compared with distal leaves of plants infected with a single aggressive isolate. Expression of Pr‐1 in plants with mixed inocula was intermediate to plants infected with an aggressive isolate (lower expression) and plants infected with a less aggressive isolate (higher expression). This suggests that wheat undergoes systemic "sensitization" by the least aggressive Z. tritici isolate during co‐infection. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive review of building materials, construction methods, and building regulations on the U.K. mainland. This provides valuable insights into the historical progression and transformation of the construction industry through a comprehensive analysis of both traditional and modern building construction materials and methods and categorising their evolutionary trajectory. Current building regulations in England, Wales, and Scotland are compared, highlighting differences in fire safety, noise safety, energy conservation, and sustainability. For example, fire safety regulations are analysed in detail, including fire resistance duration, wall cladding combustibility, and limitations on unprotected areas. Advances in knowledge and technology have led to increasingly sophisticated and energy-dependent methods, materials, and regulations. This study showcases the vast array of building construction materials spanning centuries, each possessing unique properties and performances. The selected methods and materials represent those currently employed or widely utilised in the U.K. construction industry, affirming their relevance and applicability in modern construction practices. Limitations in construction practices primarily stem from a lack of knowledge and tools rather than material scarcity. Enhancing knowledge and access to advanced tools is crucial to overcoming these limitations and driving advancements in the field. This study provides insights into the evolution of building materials, construction methods, and building regulations that can inform future developments in sustainable building practices. The findings have significant implications for policymakers, building designers, and constructors, particularly in terms of adopting sustainable materials and construction methods that comply with building regulations while reducing the environmental impact of the built environment. [ABSTRACT FROM AUTHOR]

Developing new structural materials, such as composite materials, has provided many opportunities in bridge engineering. Among these materials, glass-fiber-reinforced polymers (GFRPs), in particular, have found applications in footbridges. However, some of the commonly recognized advantages of GFRPs, such as the high values of the strength/weight ratio, can also be considered disadvantageous for certain realizations, particularly when the composite material used in a footbridge is, for example, subjected to dynamic actions such as those that are induced by wind and walking and/or running users. The induced accelerations can reach high values in comparison to recommended thresholds. Further, the natural frequency decays during the service life, reducing the capacity of the frequencies to move toward the frequency content of the pedestrian step. In this framework, the presented research is devoted to the dynamic comfort assessment of a pioneering cable-stayed GFRP pedestrian bridge, Aberfeldy, which was assembled in 1992 in the eponymous small town, which is located in Scotland (UK). The assessment was numerically performed through a finite element (FE) model, which was tuned based on the literature data concerning geometry, structural details, and in situ-acquired frequencies. The analyses carried out in this study include the evaluation of the accelerations' time histories, which were induced when simulating a set of pedestrian path scenarios, and the dynamic actions that occur during pedestrian traveling. Specifically, different values of velocity and step frequency were considered as well as the inclusion of walking and running movements. Then, based on the acceleration values, the assessments of comfort criteria for the current standards were elaborated while also recognizing that the peak accelerations—usually attained for short periods—cannot be the only parameters considered in evaluating the pedestrian bridge capacity. This investigation allowed a dynamic comfort rating to be established for the Aberfeldy footbridge. [ABSTRACT FROM AUTHOR]

Open caisson shafts are a widely adopted solution for a range of geotechnical applications. An external 'cutting shoe' is a common construction feature used to reduce the soil frictional resistance acting on the caisson during sinking. This forms an annular void encircling the caisson which is filled with a support fluid to maintain excavation stability. The primary aim of this paper is to explore the influence of the cutting shoe geometry on the resulting vertical bearing resistance in sand. Finite-element limit analysis is adopted for this purpose. Additional parameters considered in the modelling include the roughness of the caisson cutting face and cutting shoe, and the caisson radius and embedment depth. The results show that the influence of the cutting shoe is highly dependent on the caisson cutting face roughness and the soil friction angle, illustrated using detailed soil failure mechanisms. The roughness of the cutting shoe is also shown to cause a significant increase in the vertical soil reaction for large caisson embedment depths. By way of example, a recent case study in the UK, involving the construction of a 32 m dia. caisson, is used to highlight the potential influence of the cutting shoe on the bearing resistance during caisson sinking. [ABSTRACT FROM AUTHOR]

Bleeding canker of horse chestnut trees is a bacterial disease, caused by the bacterium Pseudomonas syringae pv. aesculi, estimated to be present in ~ 50% of UK horse chestnut trees. Currently, the disease has no cure and tree removal can be a common method of reducing inoculum and preventing spread. One potential method of control could be achieved using naturally occurring bacteriophages infective to the causative bacterium. Bacteriophages were isolated from symptomatic and asymptomatic horse chestnut trees in three locations in the South East of England. The phages were found to be belonging to both the Myoviridae and Podoviridae families by RAPD PCR and transmission electron microscopy. Experimental coevolution was carried out to understand the dynamics of bacterial resistance and phage infection and to determine whether new infective phage genotypes would emerge. The phages exhibited different coevolution patterns with their bacterial hosts across time. This approach could be used to generate novel phages for use in biocontrol cocktails in an effort to reduce the potential emergence of bacterial resistance.

Purpose: To model postoperative forces involved in Descemet membrane endothelial keratoplasty (DMEK) tissue adherence and bubble management, including the impact of surface tension on graft support, with a view towards clinical applications., Setting: Tennent Institute of Ophthalmology, Glasgow, and James Watt School of Engineering, University of Glasgow, Glasgow, United Kingdom., Design: Mathematical modelling and computer simulation., Methods: Theoretical modelling of biphasic flow and interaction of gas, liquid and tissue within the anterior chamber for static horizontal scenario A (adherent DMEK with mobile bubble) and dynamic vertical scenario B (release of bubble due to pupil block following DMEK)., Results: The model assumed incompressibility for both fluids within realistically achievable pressure ranges. Cahn-Hilliard Navier-Stokes equations were discretised through the application of the Finite Element Method. Mathematical modelling and computer simulation showed bubble size, corneal curvature and force intensity influences surface tension support for DMEK tissue in scenario A. Scenario B demonstrated complex, uneven distribution of surface pressure on the DMEK graft during uncontrolled bubble release. Uneven pressure concentration can cause local tissue warping, with air/fluid displacement via capillary waves generated on the fluid-air interface adversely impacting DMEK support., Conclusions: We have quantitatively and qualitatively modelled the forces involved in DMEK adherence in normal circumstances. We have shown releasing air/gas can abruptly reduce DMEK tissue support via generation of large pressure gradients at the liquid/bubble/graft interfaces, creating negative local forces. Surgeons should consider these principles to reduce DMEK graft dislocation rates via optimised bubble size to graft size, longer acting bubble support and avoiding rapid decompression where possible., (Copyright © 2023 Published by Wolters Kluwer on behalf of ASCRS and ESCRS.)