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Automated segmentation of thoracic aortic lumen and vessel wall on three-dimensional bright- and black-blood magnetic resonance imaging using nnU-Net
No full textBackground: Magnetic resonance angiography (MRA) is an important tool for aortic assessment in several cardiovascular diseases. Assessment of MRA images relies on manual segmentation, a time-intensive process that is subject to operator variability. We aimed to optimize and validate two deep-learning models for automatic segmentation of the aortic lumen and vessel wall in high-resolution electrocardiogram-triggered free-breathing respiratory motion-corrected three-dimensional (3D) bright- and black-blood MRA images. Methods: Manual segmentation, serving as the ground truth, was performed on 25 bright-blood and 15 black-blood 3D MRA image sets acquired with the iT2PrepIR-BOOST sequence (1.5T) in thoracic aortopathy patients. The training was performed with no new U-Net (nnUNet) for bright-blood (lumen) and black-blood image sets (lumen and vessel wall). Training consisted of a 70:20:10% (17/25:5/25:3/25 datasets) training:validation:testing split. Inference was run on datasets (single vendor) from different centers (UK, Spain, and Australia), sequences (iT2PrepIR-BOOST, T2 prepared coronary magnetic resonance angiography [CMRA], and time-resolved angiography with interleaved stochastic trajectories [TWIST] MRA), acquired resolutions (from 0.9–3 mm 3), and field strengths (0.55T, 1.5T, and 3T). Predictive measurements comprised Dice similarity coefficient (DSC) and Intersection over Union (IoU). Postprocessing (3D slicer) included centreline extraction, diameter measurement, and curved planar reformatting (CPR). Results: The optimal configuration was the 3D U-Net. Bright-blood segmentation at 1.5T on iT2PrepIR-BOOST datasets (1.3 and 1.8 mm 3) and 3D CMRA datasets (0.9 mm 3) resulted in DSC ≥ 0.96 and IoU ≥ 0.92. For bright-blood segmentation on 3D CMRA at 0.55T, the nnUNet achieved DSC and IoU scores of 0.93 and 0.88 at 1.5 mm³, and 0.68 and 0.52 at 3.0 mm³, respectively. DSC and IoU scores of 0.89 and 0.82 were obtained for CMRA image sets (1 mm 3) at 1.5T (Barcelona dataset). DSC and IoU scores of the BRnnUNet model were 0.90 and 0.82, respectively, for the contrast-enhanced dataset (TWIST MRA). Lumen segmentation on black-blood 1.5T iT2PrepIR-BOOST image sets achieved DSC ≥ 0.95 and IoU ≥ 0.90, and vessel wall segmentation resulted in DSC ≥ 0.80 and IoU ≥ 0.67. Automated centreline tracking, diameter measurement, and CPR were successfully implemented in all subjects. Conclusion: Automated aortic lumen and wall segmentation on 3D bright- and black-blood image sets demonstrated excellent agreement with ground truth. This technique demonstrates a fast and comprehensive assessment of aortic morphology with great potential for future clinical application in various cardiovascular diseases.</p
The Heartbeat of Global Health:Advancing Cardiovascular Care Through International Nursing Research
No full textTrapped in poverty:persistent poverty in the context of global crises
No full textThis dissertation examines how global crises shape the persistence of poverty and explores strategies for sustainable poverty reduction through the lens of poverty traps. Drawing on case studies from Sub-Saharan Africa, Paraguay, and Jordan, it investigates how urbanisation, climate shocks, and social protection design interact with chronic and transitory poverty. The first chapter analyses urban poverty in Nigeria, Tanzania, and Ethiopia. It shows that poverty in cities is marked less by fixed structural traps than by volatility, leaving the poorest behind and the near-poor at risk of slipping back. The second and third chapters focus on Paraguay and reveal a shift from chronic to transient poverty which is concentrated among rural and agricultural households, while weather shocks are shown to increase and deepen poverty, particularly in rural areas. The final chapter evaluates the impact of Jordan’s Unified Cash Transfer programme on household well-being. While it improves schooling and employment outcomes, it has limited effects on income or asset accumulation, illustrating how programme design can mitigate—or reinforce—poverty traps. Overall, the dissertation highlights the interplay of structural constraints, shocks, and social protection in poverty persistence, offering cross-country evidence and policy insights into how poverty traps emerge and how they may be overcome
Assessing Power Analysis Practices in Eyewitness Research:A Review and Simulation Study
No full textTo conduct meaningful power analyses and estimate the required sample size, researchers need to indicate which effect sizes are of practical or theoretical interest. This is especially relevant for research fields in eyewitness research (e.g., eyewitness memory, eyewitness identification, investigative interviewing) wherein findings can inform legal practice. In the present study, I examined how power analyses were conducted in 155 eyewitness articles including 353 studies with a focus on analysis of variance family-based designs and how the effect size was taken into account. None of the power analyses used meaningful effect sizes, most were irreproducible, and many did not reflect the hypothesis of interest. A simulation study showed the potential statistical power issues when the hypothesis is not accurately reflected in the power analysis. To conduct meaningful and reproducible power analyses, I recommend to set the smallest effect size of interest, conduct simulations, and provide R code to guide researchers
Masked face matching benefits from isolated facial features
No full textVerifying the identity of an unfamiliar person is a difficult task, especially when targets wear masks that cover most of their faces. This presents a major challenge for law enforcement in border control, security, and criminal investigations. Therefore, we aim to explore ways to improve face-matching performance when a face is heavily masked. In two experiments, we investigated whether face-matching performance can benefit from the presentation of isolated facial features, namely the eyes (Experiment 1) and the mouth (Experiment 2), when a target face is masked. Participants viewed pairs of faces and determined whether they belonged to the same person or different people. In congruent pairs, participants matched a full-face image to another full-face image or a masked image to an isolated facial feature. In incongruent pairs, participants matched a full-face image to an image of the eyes or the mouth only or to a masked image. Matching accuracy was significantly better in congruent than incongruent pairs. Interestingly, the benefit of showing an isolated facial feature was even present when that single feature was the mouth. Overall, the findings showed that focusing on isolated facial features, such as the eyes or mouth, can be a valuable strategy for enhancing identity matching with masked perpetrators
Cost analysis of four surgical techniques for pediatric inguinal hernia repair in a Dutch hospital
No full textIntroduction: Pediatric inguinal hernia repair (IHR) can be performed using open repair, laparoscopic approaches such as percutaneous internal ring suture (PIRS) or conventional laparoscopic IHR (LIHR) with N-/Z-suture, and robot-assisted IHR (RIHR). While extensive literature on clinical outcomes exists, cost data remain scarce. This study aims to determine the real costs of these four techniques. Methods: A retrospective cohort of consecutive patients with pediatric IHR in the past five years (2019-2023) was analyzed. Patients were grouped by technique. Individual one-year costs were collected, including pre-operative, per-operative, postoperative and complication costs. Kruskal-Wallis test was performed to compare costs between techniques. Multivariable-adjusted linear regression analyses were performed to identify factors associated with (non-OR) costs. Results: 184 patients were included in four groups: PIRS (n = 56), LIHR (n = 56), Open (n = 50), RIHR (n = 22). Total OR cost for PIRS were significantly lower than for the other laparoscopic techniques (<euro>1915 vs. <euro>2414 for LIHR; p = 0.001 and <euro>3340 RIHR; p = 0.000), but not for the open technique (<euro>1915 vs. <euro>1971; p = 1.000). They were the highest for RIHR, probably due to prolonged anesthesia time, which is explained by docking of the robotic system. Other costs of the treatment journey (excluding OR costs) were significantly associated with gestational age (4.2 % increase per week the patient was born earlier; p = 0.001), age at surgery (7 % increase per year the patient was younger; p = 0.001), reducible incarceration (40.7 % increase; p = 0.037) and recurrence (124.5 % increase; p = 0.001). Hospitalization costs were significantly higher for the open technique (38.8 % increase; p = 0.030). Discussion and conclusion: This retrospective analysis shows that the PIRS technique is related to lower OR costs. Other (non-OR) costs are highly dependent on patient characteristics and clinical outcomes. Prospective randomized studies are needed to confirm these findings and guide optimal decision making concerning surgical technique with an adequate cost-effectiveness study
Decision Making about Localized Esophageal Cancer Treatment:An Observational Study on Variation in Clinicians' Communication Behavior
No full textBackground. For localized esophageal cancer, more than 1 curative treatment option is available. As these different options are associated with substantially different treatment outcomes, decision making can be complex. Moreover, treatment decision making for a patient involves multiple health care providers (HCPs) from different disciplines over time, who might have their own role and perspective on the decision-making process. This study aims to describe how HCPs communicate during treatment decision consultations with patients with localized esophageal cancer. Methods. Audio recordings of 20 preintervention scripted standardized patient assessments (SPAs) from the SOURCE trial were used. Using 2 highly similar cases, acted by a simulated patient, considerably reduced variation at patient level. Audio recordings were content coded using open coding and rated on the degree of patient involvement in decision making using the OPTION-12. Results. Radiation and surgical HCPs discussed 1 to 4 different treatment options, from a total of 5 different options observed over all consultations. They discussed 0 to 11 different side effects and complications, from a total of 28. While some HCPs explicitly presented a choice, many used various implicit forms of suggesting a choice and either implicitly or explicitly marked their own preferences for treatment. Consultations showed a mean OPTION-12 score of 40.11 (range 0-100). Conclusions. This study shows extensive practice variation in how and to what extent standardized patients with localized esophageal cancer were involved in decision making and in the number and type of treatment options and pros and cons that were presented to them. Implications. The findings suggest a need for mutual alignment within oncologic HCPs treating patients with esophageal cancer
Adoption of twin transition technologies in developing countries:A bivariate analysis
No full textIndustrial firms worldwide face two major technological challenges: digitalizing their processes and increasing the environmental sustainability of their production. Both challenges can be addressed separately or in an integrated way. This paper empirically examines the extent to which the adoption of digital and green technologies is done in a complementary way in developing countries' industrial firms and identifies certain characteristics that tend to be present when such complementarity takes place. It also examines whether these results are consistent with or different from those observed when analyzing firms in developed economies. The analysis is based on a firm-level survey conducted by UNIDO in Ghana, Thailand, and Vietnam. The results suggest that adopting green and digital technologies are interrelated and complementary. The results align with those in developed countries, suggesting that larger green and digital firms and firms in global value chains are more likely to adopt green and digital technologies but differ in foreign ownership
