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In many plant species, suberin lamellae are deposited in the cells of the endodermis. Some cells near the xylem poles tend to remain without these lamellae and are known as ''passage cells''. To develop a three-dimensional picture of the pattern of suberin lamella deposition, procedures were developed to isolate large pieces of onion endodermis and to stain their suberin lamellae for various types of microscopy. Sudan red 7B proved satisfactory with white-light, Fluorol yellow and berberine with epifluorescence, and Nile red with confocal laser scanning microscopy (CLSM). Lamella deposition commenced in a few cells 10 mm from the root tip and then proceeded in a scattered manner. However, lamella deposition in more cells (seen 125-155 mm from the root tip) resulted in the formation of longitudinal files of cells with lamellae alternating with files of passage cells. In older regions (255-285 mm from the tip), almost all cells had deposited suberin lamellae, leaving only a few passage cells. At higher magnification, three-dimensional reconstructions of CLSM images of endodermal suberin lamellae revealed that they are perforated by pores all along the roots. Such pores could serve as points for water and ions to enter the cytoplasm of the endodermis.

Background: As programs transition to competency-based medical education (CBME), faculty development (FD) will be a key component of supporting successful implementation.Methods: Faculty at the University of Toronto (UofT) with leadership roles in residency education were invited to complete an online survey to explore their experiences with FD for CBME. Descriptive statistics were collected. Results were analyzed using thematic, frequency and comparative analyses between respondent subgroups to identify trends and theme categories relevant to the perceived most effective FD activities, most helpful FD topics as well as program/department needs for future FD initiatives. Results:The overall survey response rate was 44.6%. The most effective FD activity identified by survey respondents was a small group format. Perceived top FD topics included implementing CBME, assessment tools, feedback and coaching along with competence committees. The majority of programs felt that the ideal timing for CBME implementation was 6-12 months prior to implementation. The main perceived barrier to FD was lack of time amongst faculty.Conclusions: This data helped drive FD at UofT by supporting strategic planning for implementing competency based curricular reforms. The results have also informed the need for additional resources and enable focused FD on barriers and needs.