Leadership Development And Support: The Perceived Effects Of A Dialogic Peer Coaching Program

This formative program evaluation examined the perceptions of school-based leaders in a peer dialogic group coaching and discussion program in a larger school district in Western Canada. The pilot program included 14 principals and vice-principals from 12 different elementary or high schools who participated in either a discussion or coaching format to support and develop leadership and communication skills in six biweekly meetings over three months. Qualitative inductive content analysis was used to code and theme the data that resulted from semi-structured interviews and anonymous online surveys. Four main themes emerged from the data, and these themes described key elements of the coaching and discussion program that participants found important to program success. The first themes is Setting the Stage, which alludes to preconditions participants identified as critical to program success. The second is Shared Presence, which described the ways participants showed up to coaching or group discussions and how individuals contributed to group development. The third is Living the Learning, which explores the ways that participants perceived the structures that framed growth and support and how people participated in those structures. The fourth is The Value of Partnership, which describes the effects of the program for both individuals and the school district. This study found that participants perceived numerous elements that deserve careful consideration for program improvement or continuation. The emerging model for the program was an interconnected web of elements, each deserving of attention and important to program success. Whereas the nature of a formative assessment does not provide generalizability or transferability, this study contends that leadership program developers could benefit from a deep knowledge of program elements and an open discussion of expectations and structures going into a school-based administrator leadership and communication development and support program. Key elements include the use of a robust coaching model, having an expert resource, making the program optional and ensuring that the meetings are participant-driven

A Mid-Infrared Study of the Class 0 Cluster in LDN 1448

We present ground-based mid-infrared observations of Class 0 protostars in LDN 1448. Of the five known protostars in this cloud, we detected two, L1448N:A and L1448C, at 12.5, 17.9, 20.8, and 24.5 microns, and a third, L1448 IRS 2, at 24.5 microns. We present high-resolution images of the detected sources, and photometry or upper limits for all five Class 0 sources in this cloud. With these data, we are able to augment existing spectral energy distributions (SEDs) for all five objects and place them on an evolutionary status diagram.Comment: Accepted by the Astronomical Journal; 26 pages, 9 figure

Spherical harmonic representation of the gravitational potential of discrete spherical mass elements

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73812/1/j.1365-246X.1991.tb01157.x.pd

Observation and Assignment of Silent and Higher Order Vibrations in the Infrared Transmission of C60 Crystals

We report the measurement of infrared transmission of large C60 single crystals. The spectra exhibit a very rich structure with over 180 vibrational absorptions visible in the 100 - 4000 cm-1 range. Many silent modes are observed to have become weakly IR-active. We also observe a large number of higher order combination modes. The temperature (77K - 300K) and pressure (0 - 25KBar) dependencies of these modes were measured and are presented. Careful analysis of the IR spectra in conjunction with Raman scattering data showing second order modes and neutron scattering data, allow the selection of the 46 vibrational modes C60. We are able to fit *all* of the first and second order data seen in the present IR spectra and the previously published Raman data (~300 lines total), using these 46 modes and their group theory allowed second order combinations.Comment: REVTEX v3.0 in LaTeX. 12 pages. 8 Figures by request. c60lon

Sub-diffractional, volume-confined polaritons in a natural hyperbolic material: hexagonal boron nitride

Strongly anisotropic media where the principal components of the dielectric tensor have opposite signs are called hyperbolic. Such materials length exhibit unique nanophotonic properties enabled by the highly directional propagation of slow-light modes localized at deeply sub-diffractional scales. While artificial hyperbolic metamaterials have been demonstrated, they suffer from high plasmonic losses and require complex nanofabrication, which in turn induces the size-dependent limitations on optical confinement. The low-loss, mid-infrared, natural hyperbolic material, hexagonal boron nitride is an attractive alternative. We observe four series of multiple (up to seven) 'hyperbolic polariton' modes in boron nitride nanocones in two spectral bands. The resonant modes obey the predicted aspect ratio dependence and exhibit record-high quality factors (Q up to 283) in the strong confinement regime (lambda/86 in the smallest structures). These observations assert hexagonal boron nitride as a promising platform for studying novel regimes of light-matter interactions and nanophotonic device engineering

Small phytoplankton dominate western North Atlantic biomass

The North Atlantic phytoplankton spring bloom is the pinnacle in an annual cycle that is driven by physical, chemical, and biological seasonality. Despite its important contributions to the global carbon cycle, transitions in plankton community composition between the winter and spring have been scarcely examined in the North Atlantic. Phytoplankton composition in early winter was compared with latitudinal transects that captured the subsequent spring bloom climax. Amplicon sequence variants (ASVs), imaging flow cytometry, and flow-cytometry provided a synoptic view of phytoplankton diversity. Phytoplankton communities were not uniform across the sites studied, but rather mapped with apparent fidelity onto subpolar- and subtropical-influenced water masses of the North Atlantic. At most stations, cells < 20-µm diameter were the main contributors to phytoplankton biomass. Winter phytoplankton communities were dominated by cyanobacteria and pico-phytoeukaryotes. These transitioned to more diverse and dynamic spring communities in which pico- and nano-phytoeukaryotes, including many prasinophyte algae, dominated. Diatoms, which are often assumed to be the dominant phytoplankton in blooms, were contributors but not the major component of biomass. We show that diverse, small phytoplankton taxa are unexpectedly common in the western North Atlantic and that regional influences play a large role in modulating community transitions during the seasonal progression of blooms