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At Werrington, just north of Peterborough on the UK's East Coast main line, the formerly flat crossing of a freight line from the west (Stamford) to the east (Spalding) side of the main tracks is being replaced by a 155 m tunnel being jacked underneath at a very acute angle to create the world's longest single jacked underground structure. Two 3.5 m diameter tunnels were first driven under the railway by an earth-pressure-balanced tunnel boring machine on the precise alignment of the portal foundations, lined with concrete segments to prevent settlement of the main line before jacking, then half-filled with reinforced concrete for the portal to slide on, with side walls cast in to guide the portal round the 750 m radius curve. The 11 000 t portal was constructed on the eastern approach and jacking through the stiff clay took place during a 9-day track possession in January 2021 while a skeleton main-line service ran up the freight tracks. Steering round the bend was by a hydraulically linked lateral guidance system. The front load during jacking was less than expected and there was no side resistance at all, as the excavators and side cutters trimmed the ground accurately and the unsupported vertical clay sides held up well., At Werrington, just north of Peterborough on the UK's East Coast main line, the formerly flat crossing of a freight line from the west (Stamford) to the east (Spalding) side of the main tracks is being replaced by a 155 m tunnel being jacked underneath at a very acute angle to create the world's longest single jacked underground structure. Two 3.5 m diameter tunnels were first driven under the railway by an earth-pressure-balanced tunnel boring machine on the precise alignment of the portal foundations, lined with concrete segments to prevent settlement of the main line before jacking, then half-filled with reinforced concrete for the portal to slide on, with side walls cast in to guide the portal round the 750 m radius curve. The 11 000 t portal was constructed on the eastern approach and jacking through the stiff clay took place during a 9-day track possession in January 2021 while a skeleton main-line service ran up the freight tracks. Steering round the bend was by a hydraulically linked lateral guidance system. The front load during jacking was less than expected and there was no side resistance at all, as the excavators and side cutters trimmed the ground accurately and the unsupported vertical clay sides held up well.

Introduction and Aims: It is unclear if haemodiafiltration (HDF) improves patient survival compared to standard haemodialysis (HD). Observational studies have tended to show benefit with HDF, while meta-analyses have not provided definitive proof of superiority. This study aimed to evaluate the association between HD modality and survival in the entire Australian and New Zealand incident HD patient population. Method(s): Using data from the ANZDATA Registry, this binational inception cohort study examined all patients who commenced HD in Australia and New Zealand between 2000 and 2014. The primary outcome was all-cause mortality, measured from first HD treatment, and the secondary outcome was cardiovascular mortality. Outcomes were examined using multivariable Cox and competing risk regression analyses. Patients were censored at permanent discontinuation of HD or at 31 December 2014. Analyses were stratified by country. Result(s): The study included 26,961 patients (4110 HDF, 22,851 standard HD) with a median follow-up of 5.57 (interquartile range 3.07-8.79) years. Patients who received HDF were more likely to be obese (p<0.001) or diabetic (p<0.001), and less likely to be white (p<0.001) or aged >70 years (p<0.001). There were no differences in pre-existing cardiovascular disease (p=0.3) or vascular access (p=0.2) between groups. Compared to standard HD, HDF was associated with a significantly lower risk of all-cause mortality (adjusted HR for Australia 0.63,95% CI 0.57-0.68; adjusted HR for New Zealand 0.74, 95% CI 0.70-0.79). In Australian patients, there was an association between HDF and reduced cardiovascular mortality (adjusted SHR 0.83,95% CI 0.69-0.99). Conclusion(s): Compared tostandard HD, HDF was associated with superior survival in Australian and New Zealand patients.