Recent Gravitational Wave Observation by Pulsar Timing Arrays and Primordial Black Holes: The Importance of Non-Gaussianities.

We study whether the signal seen by pulsar timing arrays (PTAs) may originate from gravitational waves (GWs) induced by large primordial perturbations. Such perturbations may be accompanied by a sizable primordial black hole (PBH) abundance. We improve existing analyses and show that PBH overproduction disfavors Gaussian scenarios for scalar-induced GWs at 2σ and single-field inflationary scenarios, accounting for non-Gaussianity, at 3σ as the explanation of the most constraining NANOGrav 15-year data. This tension can be relaxed in models where non-Gaussianities suppress the PBH abundance. On the flip side, the PTA data does not constrain the abundance of PBHs.

Visual Thinking Strategies as a Tool for Reducing Burnout and Improving Skills in Healthcare Workers: Results of a Randomized Controlled Study.

Objective: The purpose of this study was to measure the effect that a learning method using art, such as Visual Thinking Strategies, can have on nursing students and residents in Hygiene and Preventive Medicine; we also aimed to improve skills of observation, communication, empathy and collaboration with the patient and other team members, and evaluate the impact on quality of life, burnout and positivity. Methods: The experimentation was based on administering a form (written assessment) before and after the intervention, to measure the impact of the method on improving some useful skills for the nursing and medical professions by inserting one image of an artistic type and the other of a clinical type, and asking participants to answer basic questions on the VTS method. Students participated in groups of eight in 90-min sessions for four meetings in the classroom and one at the museum, on a weekly basis. Results: The experimental study concerned a randomized controlled sample involving undergraduate nursing students who voluntarily participated in the survey. 84 students took part in the study, including 50 undergraduate nursing students (mean age 22.5, SD 2.7; 14 males and 34 females) and 34 residents in Hygiene and Preventive Medicine (mean age 28.7, SD 2.6; 8 males and 26 females). For the artistic image, the median of the total score for all skills was -1.5 for the control group and 3 for the intervention group (p = 0.002), registering an increase for the Delta identified items, which was -1.5 for the control group and 1 for the intervention group (p = 0.007). For the clinical image, the median of the total score for all skills was 0 for the control group and 2 for the intervention group (p = 0.025), recording an increase for Delta observation skills, found to be 0 for the control group and 1 for the intervention group (p = 0.007). Conclusions: Most students who participated in the intervention reported considerable improvements in the skills the method promises to improve, and a reduction in personal and work burnout scores, suggesting that the use of the VTS method in health professions curricula is viable.