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We present direct observations of acoustic waves in warm dense matter. We analyze wave-number- and energy-resolved x-ray spectra taken from warm dense methane created by laser heating a cryogenic liquid jet. X-ray diffraction and inelastic free-electron scattering yield sample conditions of 0.3$\pm$0.1 eV and 0.8$\pm$0.1 g/cm$^3$, corresponding to a pressure of $\sim$13 GPa. Inelastic x-ray scattering was used to observe the collective oscillations of the ions. With a highly improved energy resolution of $\sim$50 meV, we could clearly distinguish the Brillouin peaks from the quasielastic Rayleigh feature. Data at different wave numbers were utilized to derive a sound speed of 5.9$\pm$0.5 km/s, marking a high-temperature data point for methane and demonstrating consistency with Birch's law in this parameter regime., Comment: 7 pages, 4 figures

Warm dense matter is a region of phase space that is of high interest to multiple scientific communities ranging from astrophysics to inertial confinement fusion. Further understanding of the conditions and properties of this complex state of matter necessitates experimental benchmarking of the current theoretical models. Benchmarking of transport properties like conductivity and diffusivity has been scarce because they are small and slow processes that require micron-level resolution to see. We discuss development of a radiography platform designed to allow for measurement of these properties at large laser facilities such as the OMEGA Laser. \c{opyright} 2022 Optica Publishing Group. Users may use, reuse, and build upon the article, or use the article for text or data mining, so long as such uses are for non-commercial purposes and appropriate attribution is maintained. All other rights are reserved., Comment: 9 pages, 4 figures

Wave packet molecular dynamics (WPMD) has recently received a lot of attention as a computationally fast tool to study dynamical processes in warm dense matter beyond the Born-Oppenheimer approximation. These techniques, typically, employ many approximations to achieve computational efficiency while implementing semi-empirical scaling parameters to retain accuracy. We investigate three of the main approximations ubiquitous to WPMD: a restricted basis set, approximations to exchange, and the lack of correlation. We examine each of these approximations in atomic and molecular hydrogen in addition to a dense hydrogen plasma. We find that the biggest improvement to WPMD comes from combining a two Gaussian basis with a semi-empirical correction based on the valence-bond wave function. A single parameter scales this correction to match experimental pressures of dense hydrogen. Ultimately, we find that semi-empirical scaling parameters are necessary to correct for the main approximations in WPMD. However, reducing the scaling parameters for more ab-initio terms gives more accurate results and displays the underlying physics more readily.

We perform nonadiabatic simulations of warm dense aluminum based on the electron-force field (EFF) variant of wave-packet molecular dynamics. Comparison of the static ion-ion structure factor with density functional theory (DFT) is used to validate the technique across a range of temperatures and densities spanning the warm dense matter regime. Focusing on a specific temperature and density (3.5 eV, 5.2 g/cm3), we report on differences in the dynamic structure factor and dispersion relation across a variety of adiabatic and nonadiabatic techniques. We find the dispersion relation produced with EFF is in close agreement with the more robust and adiabatic Kohn-Sham DFT., Comment: 7 pages and 5 figures in the main manuscript; typos corrected; final version of publication

READS (Reading Enhances Achievement During Summer) has been implemented in North Carolina schools for the past several years as part of an Investing in Innovation (i3) validation grant that began in fall 2010. This paper focuses on the Year 3 study and compares the Year 3 results to the Year 1 and Year 2 results, and the results of earlier studies. The purpose of the Year 3 study was to test the effectiveness of READS-PIF (Reads with Parent Involvement and Follow-up) in a larger sample of school districts and schools. Researchers addressed three main research questions: (1) What was the overall impact of READS-PIF on students' reading comprehension?; (2) Was the impact of READS-PIF greater in high poverty schools than in moderate poverty schools?; and (3) Was the impact of READS-PIF greater for students receiving free or reduced price lunch (FRL)? This study took place in 59 elementary schools from 7 school districts in North Carolina. Of the 59 schools, 44 were high-poverty schools, and 15 were moderate-poverty schools. The final analytic sample included 5,284 students (2,798 2nd graders, and 2,486 3rd graders). Nearly 80% of the students in the study were eligible for FRL. On the spring pretest, students scored somewhat below national norms on the Iowa Tests of Basic Skills (ITBS) reading comprehension test. The sample mean normal-curve equivalent score was 46. Intervention methods included: (1) end-of-year lessons; (2) family nights; (3) tri-folds; (4) follow-up calls; and (5) book matching and summer book distribution. Within each grade and school, students were randomly assigned to the treatment or control condition and pre- and post-tested on a standardized reading comprehension test, the Iowa Tests of Basic Skills (ITBS). OLS regression was used to estimate the main effect of the treatment condition, both overall and separately by grade. To address the question of whether school poverty moderated the treatment effect, researchers included a cross-level interaction involving the student-level treatment effect and school poverty. The results suggest that the scaffolded summer reading program may be effective for third grade girls but not third grade boys. Unlike the Year 1 and Year 2 studies, the results of this study do not indicate that treatment effects are moderated by poverty measured at the school level or individual student level. Tables are appended.

The authors are presently in the fourth year of a six-year, lottery-based randomized control trial (RCT) studying the effectiveness of nine Colorado charter schools that have implemented Core Knowledge®. Core Knowledge (CK) is a comprehensive K-8 curriculum for language arts, math, science, social studies, visual arts, and music that is intended to build knowledge, concepts, and vocabulary systematically from one grade to the next, leading to substantial progress in reading. The purpose of this paper is to describe (1) a particular set of problems that arose in conducting the lottery-based RCT and (2) the solutions that we developed and implemented. The nine participating CK charters are located in six school districts that range from the suburbs south of Denver to the city of Fort Collins in the north. The participants include two cohorts of students and their parents who participated in kindergarten entrance lotteries in 2010 and 2011. Students are being tracked as they progress from kindergarten to third or fourth grade when they will take Colorado achievement tests in reading, mathematics, and writing in 2014 and 2015. In the third year of the project the authors conducted a small parent survey to assess the feasibility of individually testing Cohort 1 students in a non-school setting. The parent survey not only gave the authors access to Cohort 1 students for testing but also proved to be a valuable source of data in its own right. In fact, although it was not included in the original proposal, they have come to view it as an integral part of the lottery-based RCT, indeed the key to plans for Years 4-6. They will repeat the survey and testing process with Cohort 2.

The purpose of the Pyramid Technology Training (PTT) program was to improve teaching, learning, and school staff productivity in the Fairfax County Public Schools (Virginia). Each of 23 technology training specialists served a school pyramid and other schools in an administrative area, providing technology training, technical support, advice,and referral to other technology resources, with an emphasis on training. During the 1995-1996 school year, the Office of Program Evaluation assessed the implementation and effectiveness of PTT. The report concluded that PTT has functioned effectively over the past two years as a comprehensive and adaptive, in-school technology training and technical support program. Data demonstrate that the program has met the diverse needs of school staff, and produced practical benefits for teachers, increasing their use of technology. In addition, the data suggest that students may have increased the frequency or effectiveness of their use of technology as a result of teacher training or in-class modeling by a specialist. Two recommendations are supported by the results of the evaluation. Administrators should seek ways of: (1) increasing the availability of teachers for training and their participation in training, especially at the secondary level; and (2) reducing schools' use of the specialists to provide non-training services--technical support, advising and referral. Supporting documents are appended. (AEF)

To determine if measures of the frequency of English root words can serve as reliable predictors of knowledge of those words, a 98-item multiple choice vocabulary test, in which all of the items were English root words, was administered to 46 third graders and 45 fourth graders. The percentage of correct responses for the words was correlated with four measures of word frequency, using two methods of grouping--arithmetic and logarithmic. Three hypotheses were tested: (1) for morphologically basic (unaffixed) root words, there should be a strong relationship between word frequency and word knowledge; (2) the advantage of logarithmic grouping over arithmetic grouping should be less apparent, or non-existent, for morphologically basic words; and (3) for grouped basic words, simple item frequency would prove as strong a predictor of word knowledge as family frequency. All three of the hypotheses were confirmed. All frequency by knowledge correlations were quite high, arithmetic grouping gave the highest correlations, and simple item frequency proved to be the strongest predictor of root word knowledge. (Author/HOD)