Pure scaling operators at the integer quantum Hall plateau transition

Stationary wave functions at the transition between plateaus of the integer quantum Hall effect are known to exhibit multi-fractal statistics. Here we explore this critical behavior for the case of scattering states of the Chalker-Coddington model with point contacts. We argue that moments formed from the wave amplitudes of critical scattering states decay as pure powers of the distance between the points of contact and observation. These moments in the continuum limit are proposed to be correlations functions of primary fields of an underlying conformal field theory. We check this proposal numerically by finite-size scaling. We also verify the CFT prediction for a 3-point function involving two primary fields.Comment: Published version, 4 pages, 3 figure

Pathways to Teaching: The Cluttered Online Infrastructure for Potential Teacher Candidates

This paper examines a sampling of messages available to potential teacher candidates when searching online and querying, “How do I become a teacher?” Methodology used was discourse analysis of online search results using critical questions informed by Ellsworth’s (1997) notions of mode of address. Results reported here are from targeted searches on Google leading to hyperlink networks within institutional websites and social media platforms. In response to the search query on how to become a teacher, institutions present programmatic information that addresses viewers as already knowledgeable about the discourses of teacher education. Search results require browsers to sort through a cluttered landscape of requirements. Questions remain about whether or not there are comprehensible pathways presented to potential teacher candidates within one state context where teacher education enrollments are declining and teacher shortages exist across geographical regions and specific content positions like STEM education

Use of remotely-derived bathymetry for modelling biomass in marine environments

The paper presents results on the influence of geometric attributes of satellite-derived raster bathymetric data, namely the General Bathymetric Charts of the Oceans, on spatial statistical modelling of marine biomass. In the initial experiment, both the resolution and projection of the raster dataset are taken into account. It was found that, independently of the equal-area projection chosen for the analysis, the calculated areas are very similar, and the differences between them are insignificant. Likewise, any variation in the raster resolution did not change the computed area. Although the differences were shown to be insignificant, for the subsequent analysis we selected the cylindrical equal area projection, as it implies rectangular spatial extent, along with the automatically derived resolution. Then, in the second experiment, we focused on demersal fish biomass data acquired from trawl samples taken from the western parts of ICES Sub-area VII, near the sea floor. The aforementioned investigation into processing bathymetric data allowed us to build various statistical models that account for a relationship between biomass, sea floor topography and geographic location. We fitted a set of generalised additive models and generalised additive mixed models to combinations of trawl data of the roundnose grenadier (Coryphaenoides rupestris) and bathymetry. Using standard statistical techniques—such as analysis of variance, Akaike information criterion, root mean squared error, mean absolute error and cross-validation—we compared the performance of the models and found that depth and latitude may serve as statistically significant explanatory variables for biomass of roundnose grenadier in the study area. However, the results should be interpreted with caution as sampling locations may have an impact on the biomass–depth relationship

A Thirty State Analysis of Teacher Supervision and Evaluation Systems in the ESSA Era

We analyzed teacher supervision and evaluation policy systems in 30 states since the passage of the Every Student Succeeds Act (ESSA) of 2015 in the United States (US). This qualitative study of state ESSA policy documents and legislation examined how teacher supervision and evaluation systems (TSES) models have been developed under ESSA, specifically regarding how the construction of TSES models conflated formative feedback with summative evaluation. Despite evolving federal-level and state-level education accountability policies spurred by No Child Left Behind (NCLB) in 2001, we argue that TSES systems are influenced by state-level historical political culture (Elazar, 1994; Fowler, 2013), workplace behaviorism (Hazi, 2019), decision-making structures (Hazi & Arredondo Rucinski, 2009; Ruff, 2019), and policy rationalism (Louis et al., 2008; Orr, 2007). Data were analyzed inductively (Wolcott, 2009) to investigate how 30 states developed TSES models and from this we analyze the messages conveyed about improvement. Thus, while ESSA intended to provide states and local districts with more political control to develop and implement TSES models, our analyses shows how ESSA has extended and reinforced state-level TSES policy development and reduced districts’ local control and authority to supervise and evaluate instruction

The thermal state and interior structure of Mars

©2018. American Geophysical UnionThe present‐day thermal state, interior structure, composition, and rheology of Mars can be constrained by comparing the results of thermal history calculations with geophysical, petrological, and geological observations. Using the largest‐to‐date set of 3‐D thermal evolution models, we find that a limited set of models can satisfy all available constraints simultaneously. These models require a core radius strictly larger than 1,800 km, a crust with an average thickness between 48.8 and 87.1 km containing more than half of the planet's bulk abundance of heat producing elements, and a dry mantle rheology. A strong pressure dependence of the viscosity leads to the formation of prominent mantle plumes producing melt underneath Tharsis up to the present time. Heat flow and core size estimates derived from the InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) mission will increase the set of constraining data and help to confine the range of admissible models.DFG, 280637173, FOR 2440: Materie im Inneren von Planeten - Hochdruck-, Planeten- und Plasmaphysi

A Thirty State Analysis of Teacher Supervision and Evaluation Systems in the ESSA Era

We analyzed teacher supervision and evaluation policy systems in 30 states since the passage of the Every Student Succeeds Act (ESSA) of 2015 in the United States (US). This qualitative study of state ESSA policy documents and legislation examined how teacher supervision and evaluation systems (TSES) models have been developed under ESSA, specifically regarding how the construction of TSES models conflated formative feedback with summative evaluation. Despite evolving federal-level and state-level education accountability policies spurred by No Child Left Behind (NCLB) in 2001, we argue that TSES systems are influenced by state-level historical political culture (Elazar, 1994; Fowler, 2013), workplace behaviorism (Hazi, 2019), decision-making structures (Hazi & Arredondo Rucinski, 2009; Ruff, 2019), and policy rationalism (Louis et al., 2008; Orr, 2007). Data were analyzed inductively (Wolcott, 2009) to investigate how 30 states developed TSES models and from this we analyze the messages conveyed about improvement. Thus, while ESSA intended to provide states and local districts with more political control to develop and implement TSES models, our analyses shows how ESSA has extended and reinforced state-level TSES policy development and reduced districts’ local control and authority to supervise and evaluate instruction