Review of post-process optical form metrology for industrial-grade metal additive manufactured parts

The scope of this review is to investigate the main post-process optical form measurement technologies available in industry today and to determine whether they are applicable to industrial-grade metal additive manufactured parts. An in-depth review of the operation of optical three-dimensional form measurement technologies applicable to metal additive manufacturing is presented, with a focus on their fundamental limitations. Looking into the future, some alternative candidate measurement technologies potentially applicable to metal additive manufacturing will be discussed, which either provide higher accuracy than currently available techniques but lack measurement volume, or inversely, which operate in the appropriate measurement volume but are not currently accurate enough to be used for industrial measurement

EPIdemiology of Surgery-Associated Acute Kidney Injury (EPIS-AKI) : Study protocol for a multicentre, observational trial

More than 300 million surgical procedures are performed each year. Acute kidney injury (AKI) is a common complication after major surgery and is associated with adverse short-term and long-term outcomes. However, there is a large variation in the incidence of reported AKI rates. The establishment of an accurate epidemiology of surgery-associated AKI is important for healthcare policy, quality initiatives, clinical trials, as well as for improving guidelines. The objective of the Epidemiology of Surgery-associated Acute Kidney Injury (EPIS-AKI) trial is to prospectively evaluate the epidemiology of AKI after major surgery using the latest Kidney Disease: Improving Global Outcomes (KDIGO) consensus definition of AKI. EPIS-AKI is an international prospective, observational, multicentre cohort study including 10 000 patients undergoing major surgery who are subsequently admitted to the ICU or a similar high dependency unit. The primary endpoint is the incidence of AKI within 72 hours after surgery according to the KDIGO criteria. Secondary endpoints include use of renal replacement therapy (RRT), mortality during ICU and hospital stay, length of ICU and hospital stay and major adverse kidney events (combined endpoint consisting of persistent renal dysfunction, RRT and mortality) at day 90. Further, we will evaluate preoperative and intraoperative risk factors affecting the incidence of postoperative AKI. In an add-on analysis, we will assess urinary biomarkers for early detection of AKI. EPIS-AKI has been approved by the leading Ethics Committee of the Medical Council North Rhine-Westphalia, of the Westphalian Wilhelms-University Münster and the corresponding Ethics Committee at each participating site. Results will be disseminated widely and published in peer-reviewed journals, presented at conferences and used to design further AKI-related trials. Trial registration number NCT04165369

Filtering of FTLE for Visualizing Spatial Separation in Unsteady 3D Flow

In many cases, feature detection for flow visualization is structured in two phases: first candidate identification, and then filtering. With this paper, we propose to use the directional information contained in the finite-time Lyapunov exponents (FTLE) computation, in order to filter the FTLE field. In this way we focus on those separation structures that delineate flow compartments which develop into different spatial locations, as compared to those that separate parallel flows of different speed. We provide a discussion of the underlying theory and our related considerations. We derive a new filtering scheme and demonstrate its effect in the context of several selected fluid flow cases, especially in comparison with unfiltered FTLE visualization. Since previous work has provided insight with respect to the studied flow patterns, we are able to provide a discussion of the resulting visible separation structures

Limites de la détection par spectroscopie EPR des doses cumulées de radiations ionisantes dans les coquilles de mollusques

L'exposition des eaux aux radiations ionisantes, émises par des radionucléides stockés dans des containers de béton ou libérés lors d'accidents nucléaires ou d’iruptions sous-marines, peut être difficile à prouver lorsque des courants, des pluies et le renouvellement de l'eau et dilution des radionucléides. Les radiations ionisantes provoquent la formation de centres paramagnétiques stables dans le réseau cristallin des composants minéraux des os et dans l'exosquelette de la plupart des mollusques. Ces modifications peuvent être détectées par spectroscopie EPR et servir d'indicateurs de l'exposition aux radiations longtemps après leur action