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Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): UK Research and Innovation - Medical Research Council GW4 Studentship Background Right ventricle inflow (RV) dilation is a common adaptation to training in professional athletes, but how this impacts myocardial mechanics is yet unclear. Previous studies in athletes have found changes in segmental longitudinal strain (Sl), namely mid segment Sl, compared to normal controls, and have proposed RV dilation as a possible explanation. Whether different patterns of RV dilation are found in athletes, and if these influence regional RV mechanics is not known. Purpose To describe the patterns of RV dilation in healthy adolescent athletes and their relationship to segmental myocardial mechanics. Methods A total of 346 healthy athletes ( Results The mean (SD) age was 14.5 (1.6) years, with athletes coming from various ethnic (55% arab, 22% white and 22% black) and sports backgrounds (75% mixed, 11% power, 8% endurance and 6% skill). Based on the RV diameters, the following groups were defined: no dilation (n = 35), basal dilation (n = 53), apical dilation (n = 51) and global dilation (n = 33). There were variations in dilation pattern by ethnicity and practised sports (Figure 1). RV free wall Sl was less negative ("lower") in the apical and global dilation groups compared to the no dilation group (-26.7% and -26.4% vs -28.6%, p = 0.04 and 0.03, respectively). Mid segment Sl was consistently lower in all 3 dilation pattern groups, compared to the no dilation group (Figure 2, *denotes p Conclusions RV dilation in healthy athletes can be global, predominately basal or predominately apical. Apical and global dilation were more prevalent in non-white ethnicity, endurance and power sports. Lower mid segment Sl values were observed in all 3 dilation patterns, but FW Sl was only lower in the apical and global dilation groups. This suggests that there are different patterns of RV remodelling in athletes, which can be further characterised using segmental strain analysis. Abstract Figure. RV dilation by ethnicity and sport Abstract Figure. RV segmental strain by RV dilation

Funding Acknowledgements Type of funding sources: Other. Main funding source(s): The study was support by a contractual research partnership between the University of Bristol and Canon Medical Systems UK Background Left ventricular non-compaction (LVNC) is a rare cardiomyopathy, with hypertrabeculation often observed in athletes. In confirmed LVNC, LV systolic strain and rotational mechanics have been shown to be abnormal. Whether healthy athletes meeting echocardiographic LVNC criteria exhibit abnormal myocardial mechanics is not known. Purpose The aim of this study is to evaluate the prevalence of healthy paediatric athletes meeting the Jenni criteria for LVNC and how this relates to LV systolic function and rotational mechanics. Methods Professional athletes under 18 years undergoing comprehensive pre-participation screening (2014-2017) at two sports academies were included. Jenni criteria for LVNC were assessed from short axis LV views. Global and segmental peak systolic longitudinal (Sl) and circumferential strain (Sc), basal rotation (basal Rot) and apical rotation (apical Rot) were calculated using speckle tracking imaging. Results A total of 201 boys (11.9-18 years, median 15.1 years) were included, with diverse ethnicity (47.7% Arab, 28.5% Black, 21.8% White, and 2% other) and sports background (60% football, 21.2% athletics, 18.8% other). Of these n = 16 (8%) met the Jenni criteria for LVNC and were more likely to be of Black ethnicity than Arab or White (12.7% vs 4.4% or 9.5%). There were no differences in global, lateral or septal Sl, basal, mid or apical Sc, basal Rot or apical Rot between participants with or without Jenni criteria for LVNC (Table 1). Conclusions In healthy paediatric athletes, those meeting the criteria for LVNC (8%) do not have abnormal longitudinal, circumferential strain and rotational mechanics, compared to those without LVNC criteria. This finding supports the use of speckle tracking echocardiography as a tool in differentiating pathological changes reported in LVNC from exercise associated adaptations observed in athletes during preparticipation screening. LV mechanics Jenni criteria presence With Jenni criteria Median (IQR) Without Jenni criteria Median (IQR) p value Global LV Sl -18.6% (-19.1;-17.7) -18.6% (-19.7;-17.8) 0.7 Lateral Sl -18.3% (-18.8;-17.2) -18.5% (-19.8;-17.6) 0.5 Septal Sl -18.6% (-20.6;-17.3) -18.7% (-20.1;-17.7) 0.7 Basal LV Sc -23% (-24.6;-21.6) -23.3% (-25.7;-21.6) 0.7 Mid LV Sc -24.9% (-27.1;-23.2) -25.1% (-27.1;-22.5) 0.9 Apical LV Sc -27.8% (-32.3;-24.8) -26% (30.5;-22.4) 0.2 Basal Rot -4o (-4.7;-2.5) -3.8o (-5.3;-2.5) 0.9 Apical Rot 6.4o (5.2;7.1) 4.4 (2.9;7.1) 0.2

Funding Acknowledgements Type of funding sources: Other. Main funding source(s): The study was support by a contractual research partnership between the University of Bristol and Canon Medical Systems UK. Background Arrhytmogenic cardiomyopathy (ACM) is a major cause of sudden cardiac death among young athletes. Screening these individuals can be challenging due to right ventricular (RV) exercise-related remodelling, particularly right ventricular outflow tract (RVOT) dilation. Recent studies have also shown that peak RV longitudinal strain (Sl) measured by speckle tracking echocardiography (STE) is reduced in adolescents with definite and borderline ACM. The prevalence of RV changes meeting ACM criteria in healthy paediatric athletes, and whether these changes are associated with abnormal RV strain values is not known. Purpose The aim of this study is to evaluate the prevalence of healthy paediatric athletes meeting the ACM echocardiographic modified Task Force Criteria (mTFC) for RVOT dilation, and how this relates to RV longitudinal systolic function. Methods Athletes under 18 years old undergoing comprehensive pre-participation screening (2014-2017) at two sports academies were included. Global (RV-Sl) and free wall peak systolic strain (FW-Sl) were calculated using STE. Three groups were defined: meeting the major mTFC for RVOT size (M-mTFC), meeting the minor mTFC (m-mTFC) and not meeting the mTFC (no-mTFC). RV-Sl and FW-Sl were compared using the Kruskall Wallis test. Results A total of 247 boys (11.1-18 years, median 14.6 years) were included, with diverse ethnicity (53.1% Arab, 27.6% Black, 17.6% White, and 1.7% other) and sports background (50.6% football, 27.9% athletics, 21.5% other). Of these n = 22 were in the M-mTFC group (8.9%), n = 93 in the m-mTFC group (37.7%) and n = 132 in the no-mTFC group (53.4%). No regional RV wall motion abnormalities were observed. There were no differences in RV-Sl or FW-Sl by mTFC Group (Table 1). Conclusions In healthy paediatric athletes, 9% met the major mTFC, and 38% met the minor mTFC for RVOT size. RV longitudinal strain was found to be similar between those who met the mTFC and those who did not. This highlights the probable non-pathological adaptations reflected by RVOT dilation in these individuals, as opposed to those seen in ACM. The results of this study suggest that STE can be a valuable tool in ACM screening in paediatric athletes, especially in cases where RV remodelling is present. RV peak longitudinal strain by mTFC All M-mTFC n = 22 m-mTFC n = 93 no-mTFC n = 132 p value for between group comparison Global RV Sl (median, IQR) -23.3% (-25.2;-21.7) -23.3% (-25.5;-21.7) -23.4% (-25;-21.7) -23.3% (-25.5;-21.7) p = 0.8 Free wall RV Sl (median, IQR) 27.7% (-30;-25.2) -27.6% (-29.3;-25.2%) -28.1% (-29.7;-25) -27.5 (-30.5;-25.4) p = 0.9

BACKGROUND: Remote ischaemic conditioning with transient ischaemia and reperfusion applied to the arm has been shown to reduce myocardial infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We investigated whether remote ischaemic conditioning could reduce the incidence of cardiac death and hospitalisation for heart failure at 12 months. METHODS: We did an international investigator-initiated, prospective, single-blind, randomised controlled trial (CONDI-2/ERIC-PPCI) at 33 centres across the UK, Denmark, Spain, and Serbia. Patients (age >18 years) with suspected STEMI and who were eligible for PPCI were randomly allocated (1:1, stratified by centre with a permuted block method) to receive standard treatment (including a sham simulated remote ischaemic conditioning intervention at UK sites only) or remote ischaemic conditioning treatment (intermittent ischaemia and reperfusion applied to the arm through four cycles of 5-min inflation and 5-min deflation of an automated cuff device) before PPCI. Investigators responsible for data collection and outcome assessment were masked to treatment allocation. The primary combined endpoint was cardiac death or hospitalisation for heart failure at 12 months in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02342522) and is completed. FINDINGS: Between Nov 6, 2013, and March 31, 2018, 5401 patients were randomly allocated to either the control group (n=2701) or the remote ischaemic conditioning group (n=2700). After exclusion of patients upon hospital arrival or loss to follow-up, 2569 patients in the control group and 2546 in the intervention group were included in the intention-to-treat analysis. At 12 months post-PPCI, the Kaplan-Meier-estimated frequencies of cardiac death or hospitalisation for heart failure (the primary endpoint) were 220 (8·6%) patients in the control group and 239 (9·4%) in the remote ischaemic conditioning group (hazard ratio 1·10 [95% CI 0·91-1·32], p=0·32 for intervention versus control). No important unexpected adverse events or side effects of remote ischaemic conditioning were observed. INTERPRETATION: Remote ischaemic conditioning does not improve clinical outcomes (cardiac death or hospitalisation for heart failure) at 12 months in patients with STEMI undergoing PPCI. FUNDING: British Heart Foundation, University College London Hospitals/University College London Biomedical Research Centre, Danish Innovation Foundation, Novo Nordisk Foundation, TrygFonden. The ERIC-PPCI trial was funded by a British Heart Foundation clinical study grant (grant number CS/14/3/31002) and a University College London Hospitals/University College London Biomedical Research Centre clinical research grant. The CONDI-2 trial was funded by Danish Innovation Foundation grants (grant numbers 11-108354 and 11-115818), Novo Nordisk Foundation (grant number NNF13OC0007447), and TrygFonden (grant number 109624). DJH was supported by the British Heart Foundation (grant number FS/10/039/28270), the National Institute for Health Research (NIHR) Biomedical Research Centre at University College London Hospitals, the Duke-National University Singapore Medical School, the Singapore Ministry of Health’s National Medical Research Council under its Clinician Scientist-Senior Investigator scheme (grant number NMRC/CSA-SI/0011/2017) and its Collaborative Centre Grant scheme (grant number NMRC/CGAug16C006), and the Singapore Ministry of Education Academic Research Fund Tier 2 (grant number MOE2016-T2-2-021). HEB was supported by the Novo Nordisk Foundation (grant numbers NNF14OC0013337, NNF15OC0016674). RKK is supported by the Oxford NIHR Biomedical Centre. The research was also supported by the NIHR infrastructure at Leeds. The views expressed are those of the author(s) and not necessarily those of the National Health Service, the NIHR, or the Department of Health. This article is based on the work of COST Action EU-CARDIOPROTECTION (CA16225) and supported by COST (European Cooperation in Science and Technology). We thank all study personnel for their invaluable assistance. Sí

TZM (a high‐temperature molybdenum alloy), machinable tungsten, and 304 stainless steel were cleaned using environmentally safe, commercially available cleaning detergents. The surface cleanliness was evaluated by x‐ray photoelectron spectroscopy. It was found that a simple alkaline detergent is very effective at removal of organic and inorganic surface contaminants or foreign particle residue from machining processes. The detergent can be used with ultrasonic agitation at 140 °F to clean the TZM molybdenum, machinable tungsten, and 304 stainless steel. A citric‐acid‐based detergent was also found to be effective at cleaning metal oxides, such as iron oxide, molybdenum oxide, as well as tungsten oxides, at mild temperatures with ultrasonic agitation, and it can be used to replace strong inorganic acids to improve cleaning safety and minimize waste disposal and other environmental problems. The efficiency of removing the metal oxides depends on both cleaning temperature and time.

Explosive bonding is a bonding method in which the controlled energy of a detonating explosive is used to create a metallurgical bonding between two or more similar or dissimilar materials. Since 1991, a number of explosive bonding joints have been designed for high‐thermal‐load ultrahigh‐vacuum (UHV) components in the Advanced Photon Source. A series of standardized explosive bonded joint units has also been designed and tested, such as oxygen‐free copper (OFHC) to stainless‐steel vacuum joints for slits and shutters, GlidCop (GlidCop is a trademark of SCM Metal Products, Inc.) to stainless‐steel vacuum joints for fixed masks, and GlidCop to OFHC thermal and mechanical joints for shutter face plates, etc. The design and test results for the explosive bonding units to be used in the Advanced Photon Source front ends and beamlines will be discussed in this paper.

A set of precision horizontal and vertical white‐beam slits has been designed for the Advanced Photon Source x‐ray undulator beamlines at Argonne National Laboratory. There are several new design concepts applied in this slit set, including a grazing‐incidence knife‐edge configuration to minimize the scattering of x rays downstream, enhanced heat transfer tubing to provide water cooling, and a secondary slit to eliminate the thermal distortion on the slit knife edge. The novel aspect of this design is the use of two L‐shaped knife‐edge assemblies, which are manipulated by two precision X‐Z stepping linear actuators. The principal and structural details of the design for this slit set are presented in this paper.

A set of horizontal and vertical white‐beam slits has been designed for the Advanced Photon Source wiggler/undulator beamlines at Argonne National Laboratory. While this slit set can handle the high heat flux from one APS undulator source, it has a large enough aperture to be compatible with a wiggler source also. A grazing‐incidence, knife‐edge configuration has been used in the design to eliminate downstream x‐ray scattering. Enhanced heat transfer technology has been used in the water‐cooling system. A unique stepping parallelogram driving structure provides precise vertical slit motion with large optical aperture. The full design detail is presented in this paper.

Machinable tungsten blocks are used as safety shutters in the front ends and the beamlines at the Advanced Photon Source (APS). The machinable tungsten used is characterized as a UHV‐compatible metal by the vendor and was developed through a joint research effort with the APS. However, because of the inherent porosity in the sintered tungsten metal, it may present a vacuum problem and has to be subjected to strict vacuum testing before it is put on the beamlines. We have chosen specially heat‐treated machinable tungsten with a density of 18 g/cm3 for safety shutters. In‐house‐developed, environmentally friendly vacuum cleaning procedures were used. In this paper, we present results of thermal outgassing tests for machinable tungsten safety shutter sets. Each set consists of five blocks and has a total area of 4500 cm2. A cleaning procedure using alkaline detergent ultrasonic washes, deionized water rinses, and a 500 °C vacuum furnace baking was used before outgassing measurements. Outgassing rates 10 hours after initial pump down at room temperature reached ∼1.60×10−10 Torr⋅l⋅s−1⋅cm−2 for machinable tungsten and ∼1.56×10−10 Torr⋅l⋅s−1⋅cm−2 for the stainless steel vacuum chamber. The outgassing rate of machinable tungsten 24 hours after an in situ 48 h bake at 160 °C is also comparable to that of the stainless steel vacuum chamber. The importance of a 500 °C vacuum furnace baking has been confirmed by outgassing studies for machinable tungsten sets that were not subject to vacuum furnace baking.