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Although previous studies have examined the influence of school counselor ratios on student outcomes for various states, no prior studies of counselor ratios focused on schools in Texas. Utilizing data from the National Center for Education Statistics, the Stanford Education Data Archive, the U.S. Census Bureau, and the Texas Education Agency, we found that lower ratios were significantly associated with student achievement and dropout and graduation rates in Texas.

Despite the many expectations of school counselors in responding effectively to crisis situations, there is a lack of research and comprehensive standards that address best practices for school counselors in terms of preparing for and responding to a school shooting. Using federal guidelines and crisis literature, including studies focused on school counselors’ lived experiences of a school shooting, the author offers a research-informed theoretical framework of recommendations at different phases of a school shooting. The framework of recommendations points out probable hindrances to school counselors’ decision making. School counselors’ awareness of these impediments before experiencing each phase of such a crisis would be of benefit to them. School counselors may also use the framework of recommendations to help them assess their developmental needs in relation to preparing for and responding to a school shooting crisis.

Supervision is a critical element in the professional identity development of school counselors; however, available school counseling-specific supervision training is lacking. The authors describe a 4-hour supervision workshop based on the School Counselor Supervision Model (SCSM; Luke & Bernard, 2006) attended by 31 school counselors from three southern U.S. school districts. Employing a pre-experimental pretest-posttest research design using the Site Supervisor Self-Efficacy Survey-revised (DeKruyf, 2011), the authors found a significant positive relationship (t (30) = 9.31, p & .001; Cohen's d = 1.67) between supervision training and supervisor self-efficacy. These findings bolstered the efficacy of the SCSM. The authors discuss research and practical implications of this study.

School counselors have an ethical and professional responsibility to offer counseling services during crises such as a school shooting. Limited research has explored the lived experiences and practices of school counselors who have experienced a school shooting. This article discusses a qualitative case study investigating school counselors’ experiences related to school shootings and presents implications for school counselors.

Screened samples of two different commercial phosphors were aged at 1.5 keV under nominally identical conditions in five different vacuum systems. After aging to doses of ∼5 C/cm2 the changes in cathodoluminescence (CL) spectral output and photoluminescence properties were determined, and x-ray photoemission spectroscopy (XPS) and Auger analyses were performed. We observed that while the CL degradation was similar for all systems at low electron doses, the aging rates diverged at high doses, suggesting an increasing importance of the vacuum environment. Post-aged CL spectra showed distinct redshifts in all cases, and the most heavily degraded samples displayed XPS-determined increases in surface carbon levels. The data suggest an extrinsic CL aging mechanism; a model involving the conversion of surface hydrocarbons to a metallic graphite phase agrees with the data.

We report results of electron paramagnetic resonance, photothermal deflection spectroscopy, and capacitance‐voltage measurements on amorphous hydrogenated silicon nitride (a‐SiNx:H) thin films exposed to ultraviolet (UV) illumination. It has been previously shown that exposure to UV light activates silicon dangling‐bond defects, i.e., K0 centers, in a‐SiNx:H thin films. Here, we demonstrate that the initially UV‐activated K0 center can be irreversibly annihilated at long illumination times. Because this effect seems to scale with H content of the measured films, we propose that hydrogen may be passivating the K0 defects during the extended UV exposure. We also show that films subjected to long UV exposures trap charge as efficiently as those having much larger K0 concentrations. A few possibilities to explain this effect are discussed.

The electric field emanating from the surface of a poled ferroelectric can control the conduction properties of an overlying semiconducting film; this combination of materials can thus serve as a non-destructive readout, non-volatile memory device. Here we will describe a variety of experimental studies of these devices designed to probe the physics of their operation. The experimental systems included sputtered, n-type semiconductor (SC) films of In2O3 and ZnO deposited on bulk PLZT ferroelectrics (FE) and thin PZT FE films. Two distinctly different types of device response were measured in this study; in the first, the change in SC film conductance observed in the remanent FE state is in the direction expected from the remanent polarization vector in the ferroelectric. In the second, typically seen in thin film FE devices, the opposite behavior is observed. We find that these two general cases of behavior, including the observed variations of the SC film conductances and carrier mobilities, can...

The relatively poor efficiency of phosphor materials in cathodoluminescence with low accelerating voltages is a major concern in the design of field emission flat panel displays operated below 5 kV. Our research on rare-earth-activated phosphors indicates that mechanisms involving interactions of excited activators have a significant impact on phosphor efficiency. Persistence measurements in photoluminescence (PL) and cathodoluminescence (CL) show significant deviations from the sequential relaxation model. This model assumes that higher excited manifolds in an activator de-excite primarily by phonon-mediated sequential relaxation to lower energy manifolds in the same activator ion. In addition to sequential relaxation, there appears to be strong coupling between activators, which results in energy transfer interactions. Some of these interactions negatively impact phosphor efficiency by nonradiatively de-exciting activators. Increasing activator concentration enhances these interactions. The net effect is a significant degradation in phosphor efficiency at useful activator concentrations, which is exaggerated when low–energy electron beams are used to excite the emission.

Measurements of the threshold for secondary electron emission and shifts of the carbon Auger line position have been used to deduce the surface potential of several common phosphors during irradiation by electrons in the 0.5 – 5.0 keV range. All of the insulating phosphors display similar behavior: the surface potential is within ±1 V of zero at low electron energies. However, above 2–3 kV it becomes increasingly negative, reaching hundreds of volts within 1 keV of the turn-on energy. The electron energy at which this charging begins decreases dramatically after Coulomb aging at 17 μA/cm2 for 30–60 min‥ Measurements using coincident electron beams at low and high electron energies to control the surface potential were made to investigate the dependence of the cathodoluminescence (CL) process on charging. Initially, the CL from the two beams is identical to the sum of the separate beam responses, but after Coulomb aging large deviations from this additivity are observed. These results indicate that charging has important, detrimental effects on CL efficiency after prolonged e-beam irradiation. Measurements of the electron energy dependence of the CL efficiency before and after Coulomb aging will also be presented, and the implications of these data on the physics of the low-voltage CL process will be discussed.

We apply a number of complementary characterization techniques including electron paramagnetic resonance, optical absorption, and photoluminescence spectroscopies to characterize a wide range of different ZnO phosphor powders. We generally observe a good correlation between the 510-nm green emission intensity and the density of paramagnetic isolated oxygen vacancies. In addition, both quantities are found to peak at a free-carrier concentration ne, of about 1.4 × 1018 cm-3. We also find that the green emission intensity can be strongly influenced by free-carrier depletion at the particle surface, especially for small particles and/or low doping. Our data suggest that the green PL in ZnO phosphors is due to the recombination of electrons in singly occupied oxygen vacancies with photoexcited holes in the valence band.

We have used the highly sensitive technique of Photothermal Deflection Spectroscopy (PDS) to measure changes in the infra-red absorption spectra of MEHPPV, P3HT and Polydiacetylene-4BCMU induced by pumping these polymers with light above the π - π* transition energy. In contrast to previous chopped light transmission measurements of these effects, the PDS technique can directly measure the buildup or decay of the absorption coefficient, m, on the time scale of seconds to days. In the case of MEHPPV we observe that above-gap light causes the appearance of a broad infra-red peak in α, which continues to grow-in hours after the pump light is first applied. For this polymer the general shape of the absorption spectra in the unpumped state mimics the photo-induced changes, suggesting that remnant photo-induced states determine the maximum transparency observed under normal experimental conditions. For P3HT and to a lesser extent, MEHPPV, we also observe irreversible photo-induced absorption components which we tentatively identify with photo-induced oxidation of the polymer matrix.