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The objective of this study was to develop full body CAD geometry of a seated 50th percentile male. Model development was based on medical image data acquired for this study, in conjunction with extensive data from the open literature. An individual (height, 174.9 cm, weight, 78.6 ± 0.77 kg, and age 26 years) was enrolled in the study for a period of 4 months. 72 scans across three imaging modalities (CT, MRI, and upright MRI) were collected. The whole-body dataset contains 15,622 images. Over 300 individual components representing human anatomy were generated through segmentation. While the enrolled individual served as a template, segmented data were verified against, or augmented with, data from over 75 literature sources on the average morphology of the human body. Non-Uniform Rational B-Spline (NURBS) surfaces with tangential (G1) continuity were constructed over all the segmented data. The sagittally symmetric model consists of 418 individual components representing bones, muscles, organs, blood vessels, ligaments, tendons, cartilaginous structures, and skin. Length, surface area, and volumes of components germane to crash injury prediction are presented. The total volume (75.7 × 103 cm(3)) and surface area (1.86 × 102 cm(2)) of the model closely agree with the literature data. The geometry is intended for subsequent use in nonlinear dynamics solvers, and serves as the foundation of a global effort to develop the next-generation computational human body model for injury prediction and prevention.

This study suggests that pain, a rapidly enlarging neck mass, and younger age are predictive factors of underlying malignancy, which should prompt one to consider an aggressive diagnostic and management approach.

BackgroundFor younger generations, unconstrained online social activity is the norm. Little data are available about perceptions among young medical practitioners who enter the professional clinical arena, while the impact of existing social media policy on these perceptions is unclear.ObjectiveThe objective of this study was to investigate the existing perceptions about social media and professionalism among new physicians entering in professional clinical practice; and to determine the effects of formal social media instruction and policy on young professionals’ ability to navigate case-based scenarios about online behavior in the context of professional medicine.MethodsThis was a prospective observational study involving the new resident physicians at a large academic medical center. Medical residents from 9 specialties were invited to participate and answer an anonymous questionnaire about social media in clinical medicine. Data were analyzed using SAS 9.4 (Cary, NC), chi-square or Fisher’s exact test was used as appropriate, and the correct responses were compared between different groups using the Kruskal–Wallis analysis of variance.ResultsFamiliarity with current institutional policy was associated with an average of 2.2 more correct responses (P=.01). Instruction on social media use during medical school was related to correct responses for 2 additional questions (P=.03). On dividing the groups into no policy exposure, single policy exposure, or both exposures, the mean differences were found to be statistically significant (3.5, 7.5, and 9.4, respectively) (P=.03).ConclusionsIn this study, a number of young physicians demonstrated a casual approach to social media activity in the context of professional medical practice. Several areas of potential educational opportunity and focus were identified: (1) online privacy, (2) maintaining digital professionalism, (3) safeguarding the protected health information of patients, and (4) the impact of existing social media policies. Prior social media instruction and/or familiarity with a social media policy are associated with an improved performance on case-based questions regarding online professionalism. This suggests a correlation between an instruction about online professionalism and more cautious online behavior.Improving the content and delivery of social media policy may assist in preserving institutional priorities, protecting patient information, and safeguarding young professionals from online misadventure.

High grade astrocytomas remain incurable even though these tumors often appear localized on modern imaging studies, rarely metastasize to systemic sites, and can be aggressively treated with surgery and radiation therapy. Recent data suggest that the dissemination of astrocytoma cells along white matter tracts to distant regions of the brain may be responsible for the poor survival of these patients and the limited impact of local therapies. Movement of astrocytoma cells along these white matter tracts can be active or passive in nature. To study the potential for tumor dissemination by bulk flow of interstitial fluid resulting from peritumoral edema. 20 microL of tritiated inulin, Evans Blue, and rat albumin were injected stereotactically into the right frontal lobe and the left temporal lobe at the gray-white matter junction in Sprague-Dawley rats. Six hours later, the rats were sacrificed and the brains were removed, frozen and prepared for quantitative autoradiography and histologic analysis. Interstitial flow rates were calculated from the autoradiographs, and flow pathways were determined from the movement of Evans Blue, inulin and histologic data. In each animal injected in the frontal lobe, Evans Blue and inulin were primarily confined to large ipsilateral white matter tracts and extended from the frontal injection site to the occipital lobe. The average interstitial fluid flow rate in the association fibers of the external capsule was 0.86 mm/hr. In contrast, the animals receiving temporal lobe injections had Evans Blue and inulin confined to the temporal lobe. The average interstitial fluid flow rate in the white matter tracts of the temporal lobe was 0.61 mm/hr. The rapid and preferential flow of interstitial fluid along white matter tracts and the differences in the clearance of extracellular fluid observed between the frontal and temporal lobes may have important clinical implications. These data suggest that aggressive treatment of peritumoral edema, expansion of radiotherapy ports, and consideration of the location of the tumor in treatment planning may improve therapeutic outcomes for some patients. An improved understanding of the mechanisms of tumor dissemination is crucial to designing more effective therapeutic approaches for patients with this devastating malignancy.