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To improve the durability and bioactivity of Ti–6Al–4V alloy used for medical implants, the β-Ta2O5 nano-crystalline coatings were introduced using double cathode glow discharge technique. The coating microstructure was characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). The coating exhibits an assembly of near-equiaxed grains, locally aligned normal to the coating surface. The β-Ta2O5 coating exhibits strong adhesion to substrate and a strong resistance to deformation and cracking under applied loads. Cells culture tests showed that the coating is more beneficial to the adhesion and proliferation of NIH-3T3 cells as compared to the uncoated alloy. In-vitro bioactivity was evaluated by immersion of the coating in simulated body fluids (SBF) for different periods up to 14 days at 37 °C. The results indicated that bioactivity of Ti–6Al–4V was dramatically improved after the deposition of β-Ta2O5, since the coating has a higher apatite forming ability than the Ti–6Al–4V substrate. Finally, the electrochemical behavior of the β-Ta2O5 coating after soaking in SBF at 37 °C for 0, 3, 7, and 14 days was studied through potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). EIS measurements also confirm that the presence of a hydroxyapatite layer on the coating becomes thicker and denser during soaking in SBF. Moreover, the coating exhibits better corrosion resistance than the bare alloy. Hence, the β-Ta2O5 coating is a promising candidate coating for protection of orthopedic implants with enhanced bioactivity and corrosion resistance.

PNNL-27713 Prepared for the U.S. Department of Energy under Contract DE-AC05-76RL01830 Willamette Valley High Head Bypass Downstream Passage Prototype Evaluation: Sensor Fish Evaluation of the Regulating Outlet at Cougar Dam, 2017 Final Report November 2018 ZD Deng JP Duncan JJ Martinez T Fu CL Grant A Salalila JS CablePNNL-27713 Willamette Valley High Head Bypass Downstream Passage Prototype Evaluation: Sensor Fish Evaluation of the Regulating Outlet at Cougar Dam, 2017 Final Report ZD Deng JP Duncan JJ Martinez T Fu CL Grant A Salalila JS Cable November 2018 Prepared for the U.S. Department of Energy under Contract DE-AC05-76RL01830 Pacific Northwest National Laboratory Richland, Washington 99352iii v Summary An evaluation of the hydraulic conditions through the regulating outlet (RO) at Cougar Dam on the south fork of the McKenzie River in Oregon was conducted in November 2017 by Pacific Northwest National Laboratory (PNNL) for the U.S. Army Corps of Engineers (USACE), Portland District, concurrently with studies of passage survival and direct injury for juvenile Chinook salmon by Normandeau Associates, Inc. The RO at Cougar Dam originates in a temperature control tower that was designed to draw water from various depths in the forebay to provide water temperatures suitable for salmon in areas downstream of the dam. There are two steel-lined RO entrances controlled by headgates, located at a centerline elevation of 1488.5 ft MSL, that transition to 6.5-ft diameter pipes before merging as a common 13.5-ft-inner diameter circular steel passageway. The RO tunnel (approximately 1000 ft long) extends through rock and descends to an elevation of 1469.9 ft MSL (floor elevation) before exiting and going down 240 ft via a 20-ft-wide concrete chute with guidewalls to an elevation of 1232 ft MSL, a total distance of 426 ft. Sensor Fish data were analyzed to estimate the exposure conditions, particularly exposure to severe collision, strike, and shear events by passage route

INTRODUCTION: The Lancet Commission on Global Surgery proposed the perioperative mortality rate (POMR) as one of the six key indicators of the strength of a country's surgical system. Despite its widespread use in high-income settings, few studies have described procedure-specific POMR across low-income and middle-income countries (LMICs). We aimed to estimate POMR across a wide range of surgical procedures in LMICs. We also describe how POMR is defined and reported in the LMIC literature to provide recommendations for future monitoring in resource-constrained settings. METHODS: We did a systematic review of studies from LMICs published from 2009 to 2014 reporting POMR for any surgical procedure. We extracted select variables in duplicate from each included study and pooled estimates of POMR by type of procedure using random-effects meta-analysis of proportions and the Freeman-Tukey double arcsine transformation to stabilise variances. RESULTS: We included 985 studies conducted across 83 LMICs, covering 191 types of surgical procedures performed on 1 020 869 patients. Pooled POMR ranged from less than 0.1% for appendectomy, cholecystectomy and caesarean delivery to 20%-27% for typhoid intestinal perforation, intracranial haemorrhage and operative head injury. We found no consistent associations between procedure-specific POMR and Human Development Index (HDI) or income-group apart from emergency peripartum hysterectomy POMR, which appeared higher in low-income countries. Inpatient mortality was the most commonly used definition, though only 46.2% of studies explicitly defined the time frame during which deaths accrued. CONCLUSIONS: Efforts to improve access to surgical care in LMICs should be accompanied by investment in improving the quality and safety of care. To improve the usefulness of POMR as a safety benchmark, standard reporting items should be included with any POMR estimate. Choosing a basket of procedures for which POMR is tracked may offer institutions a