PurposeThis paper addresses the most important factors for the selection of additive manufacturing (AM) technology as a method of production of metal parts. AM creates objects by adding material layer by layer based on 3D models. At present, interest in AM is high as it is hoped that AM contributes to the competitiveness of Western manufacturing industries.Design/methodology/approachA literature study is conducted to identify the factors that affect the selection of AM technology. Expert interviews and the best–worst method are used to prioritize these factors based on relative factor weights.FindingsTechnology, demand, environment and supply-related factors are categorized and further mapped to offer a holistic picture of AM technology selection. According to expert assessments, market demand was ranked highest, although market demand is currently lacking.Research limitations/implicationsThe composition and size of the expert panel and the framing of some of the factors in light of previous literature cause validity limitations. Further research is encouraged to differentiate the selection factors for different AM implementation projects.Originality/valueThe paper presents a more complete framework of factors for innovation selection in general and the selection of AM technology specifically. This framework can serve as a basis for future studies on technology selection in the (additive) manufacturing sector and beyond. In addition to AM-specific factor weights, the paper explains why specific factors are important, reducing uncertainty for managers that have to choose between alternative manufacturing technologies.

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Aims Pharmacological termination of atrial fibrillation (AF) remains a challenge due to limited efficacy and potential ventricular proarrhythmic effects of antiarrhythmic drugs. SK channels are proposed as atrial-specific targets in the treatment of AF. Here, we investigated the effects of the new SK channel inhibitor AP14145. Methods and results Eight goats were implanted with pericardial electrodes for induction of AF (30 days). In an open-chest study, the atrial conduction velocity (CV) and effective refractory period (ERP) were measured during pacing. High-density mapping of both atrial free-walls was performed during AF and conduction properties were assessed. All measurements were performed at baseline and during AP14145 infusion [10 mg/kg/h (n = 1) or 20 mg/kg/h (n = 6)]. At an infusion rate of 20 mg/kg/h, AF terminated in five of six goats. AP14145 profoundly increased ERP and reduced CV during pacing. AP14145 increased spatiotemporal instability of conduction at short pacing cycle lengths. Atrial fibrillation cycle length and pathlength (AF cycle length × CV) underwent a strong dose-dependent prolongation. Conduction velocity during AF remained unchanged and conduction patterns remained complex until the last seconds before AF termination, during which a sudden and profound organization of fibrillatory conduction occurred. Conclusion AP14145 provided a successful therapy for termination of persistent AF in goats. During AF, AP14145 caused an ERP and AF cycle length prolongation. AP14145 slowed CV during fast pacing but did not lead to a further decrease during AF. Termination of AF was preceded by an abrupt organization of AF with a decline in the number of fibrillation waves.

Electrical impedance tomography (EIT) is a noninvasive imaging modality that allows real-time monitoring of regional lung ventilation. The aim of the study is to investigate whether fast saline infusion causes changes in lung impedance that could affect the interpretation of EIT data. Eleven pigs were anaesthetized and mechanically ventilated. A bolus of 500 mL of normal saline was administered rapidly. Two PEEP steps were performed to allow quantification of the effect of normal saline on lung impedance. The mean change of end-expiratory lung impedance (EELI) caused by the saline bolus was equivalent to a virtual decrease of end-expiratory lung volume (EELV) by 227 (188–250) mL and decremental PEEP step of 4.40 (3.95–4.59) cmH 2 O (median and interquartile range). In contrast to the changes of PEEP, the administration of normal saline did not cause any significant differences in measured EELV, regional distribution of lung ventilation determined by EIT or in extravascular lung water and intrathoracic blood volume. In conclusion, EELI can be affected by the changes of EELV as well as by the administration of normal saline. These two phenomena can be distinguished by analysis of regional distribution of lung ventilation.