Cardiovascular disease is a significant cause of morbidity and mortality in the developed world. 3D imaging of the heart's structure is critical to the understanding and treatment of cardiovascular disease. However, open-source tools for image analysis of cardiac images, particularly 3D echocardiographic (3DE) data, are limited. We describe the rationale, development, implementation, and application of SlicerHeart, a cardiac-focused toolkit for image analysis built upon 3D Slicer, an open-source image computing platform. We designed and implemented multiple Python scripted modules within 3D Slicer to import, register, and view 3DE data, including new code to volume render and crop 3DE. In addition, we developed dedicated workflows for the modeling and quantitative analysis of multi-modality image-derived heart models, including heart valves. Finally, we created and integrated new functionality to facilitate the planning of cardiac interventions and surgery. We demonstrate application of SlicerHeart to a diverse range of cardiovascular modeling and simulation including volume rendering of 3DE images, mitral valve modeling, transcatheter device modeling, and planning of complex surgical intervention such as cardiac baffle creation. SlicerHeart is an evolving open-source image processing platform based on 3D Slicer initiated to support the investigation and treatment of congenital heart disease. The technology in SlicerHeart provides a robust foundation for 3D image-based investigation in cardiovascular medicine.

BACKGROUND: Computer-intensive office work associations with health challenges may intensify following COVID-19 pandemic-related changes to home-based office work. OBJECTIVE: To determine working conditions, perception and physical elements affecting health after pivoting to full time home-work. METHODS: An online questionnaire addressed physical, productivity, motivation, and work-practice factors. Photos of the worker in their home-work environment showed side and front-back perspectives. RESULTS: Sixteen questionnaires were received, and 12 respondents supplied photos. Home and office workplace differences varied. Ten felt productivity was affected, most often positively. Four noted increased pain or fatigue intensity, particularly in the eyes, neck / head, lower back, and shoulders. Working posture was not optimal; six didn’t use traditional chair-sitting for up to half the day. Forward and backward trunk inclination accounted for at least 10% of the workday for 12 respondents; lateral inclination affected ten and eight had unsupported legs. Fifteen used an adjustable chair, but photos revealed ergonomic recommendations were not consistently followed. Fourteen participants communicated regularly by telephone, eight only for moderate duration and ten using adapted telephone equipment. Half of the ROSA scores were high. CONCLUSIONS: Workers forced into telework during the pandemic experience positive and negative impacts. Postures vary more than in offices, potentially increasing health risk.

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The different definitions of exergy efficiency (RE), which have been proposed in the past for the thermodynamic evaluation of expansion and compression devices, operating above and through ambient temperature are discussed. The comparison between these efficiencies is illustrated. An expression for (RE) based on the concept of transit exergy is presented. This concept allows the quantitative and unambiguous definition of two exergy measurements: the exergy produced and the exergy consumed. The development of these (RE) in the case of a non-adiabatic vortex tube with dimensionless thermal conductivity, integrated with a compressor above or through ambient temperature is presented. The methods of calculating the transit exergy are described. Analysis based on the mentioned measurements, combined with traditional exergy loss analysis, identifies the most important factors affecting the thermodynamic performance of compression and expansion in a non-adiabatic vortex tube. It was obtained that the use of a natural reel fluid (CO2) compared to an ideal gas (Air) increases the transit (RE) by 31.5% and decreases the exergy losses by 37.3% under the same operating conditions of the two fluids in the system with the same COP. Mots clés-Tube vortex; rendement exergétique; mesures exergétiques; exergie de transit; fluide naturel; analyse énergétique, analyse exergétique; exergie produite, exergie consommée I.