Mechanical and optical dynamic model of lung.

A multiscale, multiphysics model generates synthetic images of alveolar compression under spherical indentation at the visceral pleura of an inflated lung. A mechanical model connects the millimeter scale of an indenter tip to the behavior of alveoli, walls, and membrane at the micrometer scale. A finite-difference model of optical coherence tomography (OCT) generates the resulting images. Results show good agreement with the experiments performed using a unique indenter-OCT system. The images depict the physical result with the addition of refractive artifacts and speckle. Compression of the alveoli alters the refractive effects, which introduce systematic errors in the computation of alveolar volume. The complete computational model is useful to evaluate new proposed imaging instrumentation and to develop algorithms for obtaining quantitative data on deformation. Among the potential applications, a better understanding of recruitment of alveoli during inflation of a lung, obtained through a combination of models and imaging could lead to improvements in noninvasive treatment of atelectasis.

Will the clinicians support the researchers and teachers? Results of a salary satisfaction survey of 947 academic surgeons.

OBJECTIVE: To determine whether academic surgeons are satisfied with their salaries, and if they are willing to forego some compensation to support departmental academic endeavors. BACKGROUND: Increasing financial constraints have led many academic surgery departments to rely on increasingly on clinical revenue generation for the cross-subsidization of research and teach missions. METHODS: Members of 3 academic surgical societies (n = 3059) were surveyed on practice characteristics and attitudes about financial compensation. Univariate and multivariate logistic regression analyses were performed to identify determinants of salary satisfaction and willingness to forego compensation to support academic missions. RESULTS: One thousand thirty-eight (33.9%) surgeons responded to our survey, 947 of whom maintain an academic practice. Of these academic surgeons, 49.7% expressed satisfaction with their compensation. Length of career, administrative responsibility for compensation and membership in the American Surgical Association or the Society of University Surgeons were predictive of salary satisfaction on univariate analysis. Frequent emergency call duty, increased clinical activity, and greater perceived difference between academic and private practice compensation were predictive of salary dissatisfaction. On multivariate analysis, increased clinical activity was inversely associated with both salary satisfaction (adjusted odds ratio [AOR], 0.77; [95% CI: 0.64, 0.94]; P = 0.009) and amount of compensation willingly killed for an academic practice (AOR, 0.71; [0.61, 0.83]; P < 0.0005). CONCLUSIONS: Increasing reliance on clinical revenue to subsidize nonclinical academic missions is disaffecting many academic surgeons. Redefined mission priorities, enhanced nonfinancial rewards, utilization of nonclinical revenue sources (eg, philanthropy, grants), increased efficiency of business practices and/or redesign of fund flows may be necessary to sustain recruitment and retention of young academic surgeons.