To Group or Not to Group: A Qualitative Study of Middle School Principals\u27 Decision Making Processes Concerning Ability Level Grouping.

The topic of ability level grouping of students for instructional purposes is one of the most studied areas of research in educational literature. However, because of the inconclusive findings in the literature, no clear answer to the question of whether homogeneous or heterogeneous grouping is in the best educational interest of students has been established. Middle level administrators play a particularly important role in the debate concerning the use of ability grouping in individual schools because the pattern for future educational tracks of students is established at the middle level. An exploration of the factors that affect the decision making processes of middle school principals concerning whether to implement homogeneous versus heterogeneous grouping was deemed to be important in lending understanding to practitioners in the field faced with the responsibility of implementation of middle school programming. The purpose of this qualitative study was to explore the factors that influence middle level principals in the east Tennessee region when deciding to implement homogeneous or heterogeneous grouping of students in their schools. Data were collected through a series of audio taped interviews and transcribed for inductive analysis. Themes that emerged from the data analysis of the open-ended interviews were deducted into findings presented within the context of reviewed literature. The impact of student achievement, standardized test accountability, social factors that affect students, the perceptions of teachers and parents, programming for special education and gifted students, the impact of educational research, and the personal philosophies of the research participants concerning homogeneous versus heterogeneous instruction emerged as influential themes that affected principals\u27 decisions to implement ability level grouping. Specific recommendations for educational practice included the implementation of ability grouping at the middle level exclusively in the areas of mathematics, language, and reading, flexible scheduling that allows for movement of students between groups, and changing the yearly assignment of teachers to a specific ability group for instruction. The need for additional quantitative and qualitative research was also suggested

Chemistry and Apparent Quality of Surface Water and Ground Water Associated with Coal Basins

Personnel of the Arkansas Mining and Mineral Resources Research Institute conducted preliminary investigations on the chemistry and quality of surface and ground water associated with 12 coal-bearing sub-basins in the Arkansas Valley coal field. The coal field is approximately 60 miles long and 33 miles wide but only in 12 areas coal is thick enough and has proper quality to be termed commercial. Both surface and underground sample sites were established in each of the sub-basins with some minor variations in four areas where not all types of sites could be located. Water was collected from 19 surface points and 19 underground points in the established areas. Both field and laboratory analyses were made and elemental contents are reported herein. In the main, the chemistry and water quality suggests that all water is suitable for agricultural and industrial uses. To obtain potable water, treatment must be made to reduce calcium, magnesium, sodium sulfate and iron. The mineral content of the water is due to its contact with coal-bearing zones and, as such, reflects the mineral content of the coal. However, it is recommended that additional studies on the petrography and geochemistry of the coal, overburden and underburden is in order. Also, it is recommended that at least one detailed study be made of one of the coal sub-basins where geologic parameters can be completely established with regard to hydrogeology. This report is an important first step in determining the character and quality of Arkansas coal which must be fully understood to fully utilize this important mineral resource

Normal and Abnormal Personality Traits are Associated with Marital Satisfaction for both Men and Women: An Actor–Partner Interdependence Model Analysis

Research has demonstrated associations between relationship satisfaction and personality traits. Using the Actor–Partner Interdependence Model, we explored associations between self-reported relationship satisfaction in couples (n = 118) and various measures of normal and abnormal personality, including higher-order dimensions of PE/Extraversion, NE/Neuroticism, Constraint (CON), and their lower-order facets. We also examined gender differences and moderators of associations. Consistent with the Vulnerability Stress Adaptation Model, self- and partner-reported NE and PE were related to satisfaction, and their lower-order traits demonstrated differential associations with satisfaction. Further, abnormal personality traits specific to the interpersonal domain and personality disorder symptoms demonstrated effects. Relationship length emerged as a significant moderator, with associations weakening as relationship duration increased

PASCO: Structural panel analysis and sizing code: Users manual - Revised

A computer code denoted PASCO is described for analyzing and sizing uniaxially stiffened composite panels. Buckling and vibration analyses are carried out with a linked plate analysis computer code denoted VIPASA, which is included in PASCO. Sizing is based on nonlinear mathematical programming techniques and employs a computer code denoted CONMIN, also included in PASCO. Design requirements considered are initial buckling, material strength, stiffness and vibration frequency. A user's manual for PASCO is presented

Enduring Extremes? Polar Vortex, Drought, and Climate Change Beliefs

This is the author accepted manuscript. The final version is available from Taylor & Francis via the DOI in this recordSome extreme weather events may be more likely to affect climate change beliefs than others, in part because schema individuals possess for different events could vary in encouraging such links. Using a representative sample of U.S. adults and geocoded National Weather Service data, we examine how a range of extreme weather event categories relate to climate change beliefs, and the degree to which individuals’ self-reported experiences are shaped by their political views across event types. For tornado, hurricane, and flood events, we find no link with beliefs. For polar vortex and drought events, we find that although self-reported experience is linked with climate beliefs, reporting of these experiences is influenced by political identity and partisan news exposure. These findings underscore a limited role for extreme weather experiences in climate beliefs, and show that events more open to interpretation, such as droughts and polar vortex disturbances, are most likely to be seen through a partisan lens.This work was supported by H2020 European Research Council [grant number 682758]

Nanomechanical-resonator-induced synchronization in Josephson junction arrays

We show that a serial array of N nonuniform, underdamped Josephson junctions coupled piezoelectrically to a nanoelectromechanical (NEM) oscillator results in phase locking of the junctions. Our approach is based on a semiclassical solution to a set of coupled differential equations that were generated by the Heisenberg operator equations, which in turn are based on a model Hamiltonian that includes the following effects: the charging and Josephson energies of the junctions, dissipation in the junctions, the effect of a dc bias current, an undamped simple harmonic oscillator (representing the NEM), and an interaction energy (due to the piezoelectric effect) between the NEM and the junctions. Phase locking of the junctions is signaled by a step in the current-voltage (I-V) curve. We find the phase-locked states are (neutrally) stable at the bottom and top of the step but not for bias currents in the middle of the step. Using harmonic balance, we are able to calculate an analytical expression for the location of the resonance step, v_step, in the I-V curve. Because of the multistability of the underdamped junctions, it is possible, with a judicious choice of initial conditions and bias current, to set a desired number N_a≤N of junctions on the resonance step, with N−N_a junctions in the zero-voltage state. We are also able to show that, when Na junctions are in the phase-locked configuration, the time-averaged energy of the NEM oscillator scales like N_a^2

Surface-Enhanced Plasmon Splitting in a Liquid-Crystal-Coated Gold Nanoparticle

We show that, when a gold nanoparticle is coated by a thin layer of nematic liquid crystal, the deformation produced by the nanoparticle surface can enhance the splitting of the nanoparticle surface plasmon. We consider three plausible liquid crystal director configurations in zero electric field: boojum pair (north-south pole configuration), baseball (tetrahedral), and homogeneous. From a calculation using the Discrete Dipole Approximation, we find that the surface plasmon splitting is largest for the boojum pair, intermediate for the homogeneous, and smallest for the baseball configuration. The boojum pair results are in good agreement with experiment. We conclude that the nanoparticle surface has a strong effect on the director orientation, but, surprisingly, that this deformation can actually enhance the surface plasmon splitting.Comment: 5 pages, 3 figures To be published in PR

Synchronization in disordered Josephson junction arrays: Small-world connections and the Kuramoto model

We study synchronization in disordered arrays of Josephson junctions. In the first half of the paper, we consider the relation between the coupled resistively- and capacitively shunted junction (RCSJ) equations for such arrays and effective phase models of the Winfree type. We describe a multiple-time scale analysis of the RCSJ equations for a ladder array of junctions \textit{with non-negligible capacitance} in which we arrive at a second order phase model that captures well the synchronization physics of the RCSJ equations for that geometry. In the second half of the paper, motivated by recent work on small world networks, we study the effect on synchronization of random, long-range connections between pairs of junctions. We consider the effects of such shortcuts on ladder arrays, finding that the shortcuts make it easier for the array of junctions in the nonzero voltage state to synchronize. In 2D arrays we find that the additional shortcut junctions are only marginally effective at inducing synchronization of the active junctions. The differences in the effects of shortcut junctions in 1D and 2D can be partly understood in terms of an effective phase model.Comment: 31 pages, 21 figure