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Achieving fundamental understanding of insulator-to-metal transitions (IMTs) in strongly correlated systems and their persistent and reversible control via nonequilibrium drive are prime targets of current condensed matter research. Photoinduced switching between competing orders in correlated insulators requires a free-energy landscape with nearly degenerate ground states, which is commonly reached through doping, strain, or static electric field. The associated spatial inhomogeneity leads to a photoinduced phase transition that remains confined near the illuminated region. Here we report optical spectroscopy experiments at the first-order IMT in the 4d-electron compound Ca$_3$(Ru$_{0.99}$Ti$_{0.01}$)$_2$O$_7$ and show that specific Ru d-d interband transitions excited by light with a threshold fluence corresponding to the planar density of Ru atoms can trigger reversible, avalanche-like coherent propagation of phase interfaces across the full extent of a macroscopic sample, in the absence of assisting external stimuli. Based on detailed comparison of spectroscopic data to density functional calculations, we attribute the extraordinary photo-sensitivity of the IMT to an exceptionally shallow free-energy landscape generated by the confluence of electron-electron and electron-lattice interactions. Our findings suggest Ca$_3$(Ru$_{0.99}$Ti$_{0.01}$)$_2$O$_7$ as an ideal model system for building and testing a theory of Mott transition dynamics in the presence of strong electron-lattice coupling and may pave the way towards nanoscale devices with quantum-level photosensitivity., Comment: 24 pages, 8 figures, 3 ancillary video files

The temperature dependence of the superfluid density $\rho_s(T)$ has been measured for a series of ultrathin MBE-grown DyBa$_2$Cu$_3$O$_{7-\delta}$ superconducting (SC) films by sub-mm wave interferometry combined with time-domain THz spectroscopy and IR ellipsometry. We find that all films 10 u.c. and thicker show the same universal temperature dependence of $\rho_s(T)$, which follows the critical behavior characteristic of single crystal YBa$_2$Cu$_3$O$_{7-\delta}$ as $T$ approaches $T_c$. In 7 u.c. thick films, $\rho_s(T)$ declines steeply upon approaching $T_c$, as expected for the Berezinskii-Kosterlitz-Thouless vortex unbinding transition. Our analysis provides evidence for a sharply defined 4 u.c. non-SC interfacial layer, leaving a quasi-2D SC layer on top. We propose that the SC state in this interfacial layer is suppressed by competing (possibly charge) order., Comment: 6 pages, 3 figures

We present new molecular modelling for 14NO and 15NO and a deep, blind molecular line survey at low radio frequencies (99-129 MHz). This survey is the third in a series completed with the Murchison Widefield Array (MWA), but in comparison with the previous surveys, uses four times more data (17 hours vs. 4 hours) and is three times better in angular resolution (1' vs. 3'). The new molecular modelling for nitric oxide and its main isotopologue has seven transitions within the MWA frequency band (although we also present the higher frequency transitions). Although we did not detect any new molecular lines at a limit of 0.21 Jy beam^-1, this work is an important step in understanding the data processing challenges for the future Square Kilometre Array (SKA) and places solid limits on what is expected in the future of low-frequency surveys. The modelling can be utilised for future searches of nitric oxide., Comment: 13 pages, 5 figures, 1 table, accepted by Astrophysical Journals (ApJ)

Using a combination of infrared ellipsometry, time-domain terahertz spectroscopy, and far-infrared reflectometry we have obtained the $ac$-plane complex dielectric function of monoclinic ($C2/c$) Ta$_2$NiSe$_5$ and orthorhombic ($Cmcm$) Ta$_2$NiS$_5$ single crystals. The identified dipole-active phonon modes polarized along $a$ and $c$ axes are in good agreement with density functional theory calculations. With increasing temperature the $a$-axis phonon modes of Ta$_2$NiSe$_5$ become poorly discernible, as they are superimposed on the electronic background which gradually fills the energy gap near the monoclinic-to-orthorhombic phase transition temperature $T_c$ = 326 K. In Ta$_2$NiS$_5$, which does not exhibit such a structural transition and remains orthorhombic down to low temperatures, the $a$-axis phonon modes are superimposed on a persistent broad electronic mode centered near 16 meV. We attribute this difference to strongly overlapping exciton-phonon complexes in Ta$_2$NiSe$_5$, as opposed to isolated instances of the same in Ta$_2$NiS$_5$, and find this to be in good agreement with an excitonic insulator state below $T_c$ in the former, as compared to the absence of one in the latter., Comment: 10 pages, 7 figures

Directly detecting thermal emission from young extrasolar planets allows measurement of their atmospheric composition and luminosity, which is influenced by their formation mechanism. Using the Gemini Planet Imager, we discovered a planet orbiting the \$sim$20 Myr-old star 51 Eridani at a projected separation of 13 astronomical units. Near-infrared observations show a spectrum with strong methane and water vapor absorption. Modeling of the spectra and photometry yields a luminosity of L/LS=1.6-4.0 x 10-6 and an effective temperature of 600-750 K. For this age and luminosity, "hot-start" formation models indicate a mass twice that of Jupiter. This planet also has a sufficiently low luminosity to be consistent with the "cold- start" core accretion process that may have formed Jupiter., Comment: 29 pages, 3 figures, 2 tables, and Supplementary Materials. published in Science Express on Aug 13 2015. List of authors and the magnitudes of the star were correted

We discuss the design, operation, and performance of a vacuum setup constructed for use in zero (or reduced) gravity conditions to initiate collisions of fragile millimeter-sized particles at low velocity and temperature. Such particles are typically found in many astronomical settings and in regions of planet formation. The instrument has participated in four parabolic flight campaigns to date, operating for a total of 2.4 hours in reduced gravity conditions and successfully recording over 300 separate collisions of loosely packed dust aggregates and ice samples. The imparted particle velocities achieved range from 0.03-0.28 m s^-1 and a high-speed, high-resolution camera captures the events at 107 frames per second from two viewing angles separated by either 48.8 or 60.0 degrees. The particles can be stored inside the experiment vacuum chamber at temperatures of 80-300 K for several uninterrupted hours using a built-in thermal accumulation system. The copper structure allows cooling down to cryogenic temperatures before commencement of the experiments. Throughout the parabolic flight campaigns, add-ons and modifications have been made, illustrating the instrument flexibility in the study of small particle collisions., Comment: D. M. Salter, D. Hei{\ss}elmann, G. Chaparro, G. van der Wolk, P. Rei{\ss}aus, A. G. Borst, R. W. Dawson, E. de Kuyper, G. Drinkwater, K. Gebauer, M. Hutcheon, H. Linnartz, F. J. Molster, B. Stoll, P. C. van der Tuijn, H. J. Fraser, and J. Blum

Social desirability responding (SDR) on surveys administered on the World Wide Web and on paper was examined, with 178 graduate and undergraduate students as participants. To assess the extent to which participants would demonstrate SDR, this study used the Balanced Inventory of Desirable Responding (BIDR) (Paulhus, 1993). The BIDR consists of 40 items states as propositions. Respondents rate their agreement with each statement on a seven-point scale. Using a true experimental design, the study examined the impact of two independent variables, the participants' identifiability level (anonymous and non-anonymous) and the survey's administration mode (World Wide Web-administered and paper-administered), on one dependent variable, the participants' social desirability response levels measured by the BIDR. Findings reveal no differences in SDR between the Web and the paper-administered survey conditions, and no differences in SDR between the anonymous and non-anonymous conditions. These findings and potential explanations are examined for consideration by anyone interested in using the Web to obtain accurate information from survey participants. (Contains 35 references.) (AEF)

The main effects and interactions of a teacher's instructional methods (direct/nondirect) and students' conceptual levels (high/low) on the students' motivation to learn academic course content were studied with 65 college students in an introductory educational technology class. Students completed a measure designed to indicate their conceptual level and received direct or nondirect instruction according to T. Cicchelli's classification (1983). There was no statistically significant interaction between instructional strategy and conceptual level on students' motivation to learn course content. On the contrary, there was a statistically significant main effect for instructional groups in that students in the nondirect instruction treatment, regardless of conceptual level, demonstrated much higher motivation levels than student exposed to direct instruction. (Contains 2 tables and 10 references.) (SLD)

The University of North Carolina at Charlotte's "Seven-Year Student Development Plan" identified phases, steps, goals, and activities associated with attracting and supporting undergraduate, postbaccalaureate, and graduate students prior to, during, and for 1 year after their enrollment in the university's teacher education program. Phase 1 of the development of the plan involved advertisement, recruitment, and initial student orientation. Many of the Phase 1 actions capitalized on the ongoing activities of other campus offices. Significant efforts were devoted to direct correspondence with students in local high schools and community colleges. The school had difficulty recruiting ethnic minorities. Phase 2 involved orientation, socialization, academic advising, and preparation for teacher education. The first year of implementing the plan suggested that the steps and goals of Phase 2 were satisfactory, though about 20 percent of freshman and sophomore pre-education students changed their majors out of education, and there were no attempts to determine the reason for departure. Phase 3 involved academic advising, student teaching, and teacher licensure. This stage was also satisfactory. However, student scores on the Praxis II Specialty Area tests were low, so students need more help preparing for them. Phase 4 involved graduate surveys and review/revision of the "Seven-Year Student Development Plan." Results found that graduates were positive about the program. The employment rate for the graduates in local school districts was about 93 percent. (SM)

Applies three factors of expectancy theory (estimations of the likelihood of success, likelihood that a behavior will result in certain outcomes, and positive or negative value placed on each outcome) to faculty academic advising. Identifies educational environments and activities conducive to use of the theory to enhance faculty motivation for advising. (Author/MSE)

Reviews the application of expectancy theory to student motivation. Describes tenets of the theory (motivation depends on estimation of the likelihood of success, the likelihood that particular behaviors will result in the outcome, and the value of outcomes). Identifies instructor actions related to each tenet that can enhance student motivation. (20 citations) (MAB)

The effects of students' conceptual levels and teachers' instruction patterns on students' motivation to learn academic course content were investigated. An examination of 63 students indicated that for low-conceptual-level students, direct teaching methods maximized motivation to learn course content. For high-conceptual-level students, nondirect instruction significantly enhanced motivation. (Author/SM)

Describes activities of the Office of Student Academic Services that was developed at the University of North Carolina at Charlotte to support the needs of students enrolled in teacher education programs. Pre-enrollment steps, a pre-teacher education program, the teacher education phase, and a post-graduation phase are discussed. (LRW)

The Plane Wave Approximation (PWA) is widely used in finite element analysis to implement the loading generated by an underwater shock wave. The method required to implement the PWA in NASTRAN is presented along with example problems. A theoretical background is provided and the limitations of the PWA are discussed.

Project D.A.R.E. (Development through Adventure, Responsibility and Education), an adventure-based outdoor program, uses a feedback/evaluation model, combining a learning component with a two-part participant observational model. The first phase focuses on evaluation of the child and progress made while he is in the program (stages one to four); the second is evaluation of the child by the referring agency, after the program concludes (stage five). Initially, the referring agency identifies one or more goals for each participant, to guide staff members in treatment of individuals. After five or six days, the staff team reviews goals set for each individual and establishes his learning stage. Midway through the program, the staff reviews each child's progress through learning stages of the goals. On the last program day, each child has a conference with the staff to assess his progress, which forms the basis for graduation from the program. A post evaluation of each graduate is carried out by the referring agency, using the goals originally specified for each individual; if the child has retained some progress made in the learning stages of specified goals, the program is considered to have had a significant impact. Appendixes contain instruments used in the program. (CM)

A study of small gas turbine engines was conducted to identify high payoff technologies for year-2000 engines and to define companion technology plans. The study addressed engines in the 186 to 746 KW (250 to 1000 shp) or equivalent thrust range for rotorcraft, commuter (turboprop), cruise missile (turbojet), and APU applications. The results show that aggressive advancement of high payoff technologies can produce significant benefits, including reduced SFC, weight, and cost for year-2000 engines. Mission studies for these engines show potential fuel burn reductions of 22 to 71 percent. These engine benefits translate into reductions in rotorcraft and commuter aircraft direct operating costs (DOC) of 7 to 11 percent, and in APU-related DOCs of 37 to 47 percent. The study further shows that cruise missile range can be increased by as much as 200 percent (320 percent with slurry fuels) for a year-2000 missile-turbojet system compared to a current rocket-powered system. The high payoff technologies were identified and the benefits quantified. Based on this, technology plans were defined for each of the four engine applications as recommended guidelines for further NASA research and technology efforts to establish technological readiness for the year 2000.

Intermediate payload launch vehicle using solid rocket motors in cluster as first stage and Saturn S-4B as second stage

Literature survey and experiments on stress deformation characteristics of solids under static loading

High temperature calorimetry - enthalpy of sodium chloride and aluminum oxide

High temperature calorimeter and measurements of enthalpies of alpha-aluminum oxide and sodium chloride